Our Mission: To deliver life-saving neuro solutions and support you can count on.

Codman Neuro Pinewood Campus, Nine Mile Ride Wokingham, Berkshire, England RG40 3EW Tel: +44 (0) 134 486 4000 www.depuysynthes.com

Registered Address: Johnson & Johnson Medical Limited, PO BOX 1988, Simpson Parkway, Livingston, West Lothian EH54 0AB United Kingdom. Incorporated and registered in Scotland under company number SC132162. ©Codman Neuro, a division of Johnson & Johnson Medical Limited. 07/14. All rights reserved. DSEM/COD/0614/0074 Table of Contents

4 Welcome 5 President’s message 6 Sponsorship 7 Supporting partners 8 ISHCSF details 10 Registraion times/Useful information 12 Social programme 14 Venue map and floorplan 17 Faculty 18 Faculty: Invited speakers 22 IHIWG information 24 Special session 26 Sponsored sessions 27 NPH Educational symposium timetable 28 Overview of scientific programme 30 Detailed scientific programme 48 Abstracts 95 Poster Abstracts 119 Author index

3 Welcome

Dear Colleague,

On behalf of the International Society for Hydrocephalus and Cerebrospinal Fluid Disorders (ISHCSF) it gives me great pleasure to welcome you to Hydrocephalus 2014, Bristol, U.K. The meeting has attracted around 300 delegates with a further 100 attending the satellite Educational Symposium on Normal Pressure Hydrocephalus. This latter event is designed to raise awareness amongst clinicians of the growing importance of NPH as a treatable cause of cognitive impairment and falls in the elderly.

The Congress will cover the full range of CSF disorders affecting both children and adults and has attracted a large number of delegates from a number of disciplines from around the world. For the first time we are able to offer a simultaneous translation service for colleagues from China, and I hope this will represent the start of an increase in interest in the ISHCSF from clinicians from this country. Hydrocephalus2014 has moved with the times and for the first time we have a conference “app” for the iPad and a live Twitter feed for the meeting itself. This year we have an exciting special session on Visual Impairment / Intracranial Pressure (VIIP) a condition affecting astronauts undertaking prolonged space flights such as a planned Mars mission. This session is in collaboration with the Baylor College of Medicine Center for Space Medicine, who work closely with NASA. We will also have sessions dedicated to advanced Neuro-imaging techniques in hydrocephalus and on CSF shunt design and technology. It is also a great pleasure to welcome colleagues from the International Hydrocephalus Imaging Working Group (IHIWG), neuroimaging remains an integral part of research into hydrocephalus and the presence of Neuroradiologists and Physicists at this conference is invaluable.

We have an impressive group of invited speakers from a wide range of disciplines. The programme has been designed to facilitate a true interdisciplinary exchange of ideas to help speed progress to improving the diagnosis and treatment of hydrocephalus and CSF disorders.

Bristol is an historic city in the west of England. It lies at the heart of the English ‘west country’ and is surrounded by the beautiful Cotswold countryside and is located close to the ancient Roman city of Bath. The prehistoric monument Stonehenge lies deep in the Wiltshire countryside to the south of Bristol and is also well worth a visit if you have time. The meeting itself will be held in the spectacular Wills Memorial building, part of Bristol University which will be an impressive backdrop to what promises to be an exciting meeting.

Finally, I would like to offer our grateful thanks to the industry sponsors who have supported this meeting, please take time to visit their stands.

Best wishes

Richard J Edwards BSc MBBS FRCS(Eng) FRCS(Neuro.Surg) MD Congress President, Hydrocephalus 2014 – Bristol The 2014 Meeting of the International Society for Hydrocephalus and CSF Disorders

4 ISHCSF President’s Message

On behalf of the Board of Directors, welcome to Hydrocephalus 2014, the Sixth meeting of the International Society for Hydrocephalus and CSF Disorders.

This year’s conference follows the tradition of annual meetings since our founding at the Hydrocephalus 2008 conference in Hannover, Germany, including meetings in Baltimore (2009), Crete (2010), Copenhagen (2011), Kyoto (2012), and Athens (2013).

I wish to acknowledge, honor, and thank the Congress President, Richard Edwards, MD, for his tireless perseverance in organizing what promises to be an outstanding meeting with fresh science, novel insights by a stellar panel of invited speakers, and opportunities for all of us to meet old and new friends, and establish new collaborations. I wish also to extend thanks to our industry sponsors and partners for their continued support of our meetings, which are the lifeblood of the ISHCSF.

Lastly, thanks to you, our members and attendees for traveling to Bristol to share your work, which represents the collective effort of hundreds of the brightest minds in our field from all areas of the globe, and helps us to achieve the mission of the ISHCSF, which is to advance the art and science of the field of clinical care and research in hydrocephalus and CSF disorders, and thereby promote the best possible care for patients with hydrocephalus and CSF disorders.

Welcome to Bristol!

Michael A. Williams, MD President ISHCSF

5 Sponsorship

Platinum Sponsor

Our Mission: To deliver life-saving neuro solutions and support you can count on

Codman, a division of Johnson & Johnson, is a global neuroscience company that develops and markets a wide range of devices and solutions for the diagnosis and treatment of neurological disorders. The company’s leading solutions include programmable as well as fixed pressure shunt systems, antimicrobial impregnated catheters, intra-cranial pressure monitoring devices, electro-surgery and cranial closure products, interventional neurovascular coils, catheters, vascular reconstruction and thrombectomy devices. Codman is proud to be a reliable long-term partner to the International Society of Hydrocephalus and CSF disorders.

Gold Sponsors

Medtronic is the global leader in medical technology- alleviating pain, restoring health, and extending life for millions of people around the world. Medtronic develops and manufactures a wide range of products and therapies with emphasis on providing a complete continuum of care to diagnose, prevent and monitor chronic conditions. Every five seconds, somewhere in the world, a person’s life is saved or improved by a Medtronic product or therapy. We look forward to having an opportunity to introduce you to a number of exciting new market leading technologies which we have launched this year designed to complement and enhance our comprehensive portfolio.

Neurosurgery and Aesculap are inseparably connected with each other. Aesculap is since 1867 a leading manufacturer of highest quality products for the treatment of cerebrovascular disorders, cranio-spinal tumours and hydrocephalus with products like Yasargil® aneurysm clips & micro instruments, CranioFix® bone flap fixation, Aesculap-Miethke proGAV® and proSA® programmable hydrocephalus valves and much more.

Silver Sponsor

Caring for life, at Fannin we provide the medical devices, medicines and diagnostic products that help healthcare professionals and patients across the Island of Ireland and the UK manage illness and restore health. But what we deliver is more than simply the mechanics of treatment. We seek to be the best service provider of Medical Devices, Medicines and Services to the healthcare sector.

6 Bronze Sponsor

Renishaw is a global company with core skills in measurement, motion control, spectroscopy and precision machining. We develop innovative products that significantly advance our customers’ operational performance - from improving manufacturing efficiencies and raising product quality, to maximising research capabilities and improving the efficacy of medical procedures.

Supporting Partners & Exhibitors

Supporting Partners

Circle Bath Hospital

Exhibitors

Karl Storz Integra Sophysa BK Medical Delta-Surgical Likvor BrainLab

7 Welcome to the ISHCSF

The ISHCSF was inaugurated in September 2008 and registered as a non-profit organization in December of the same year. From the beginning, its mission has been to advance the art and science of the field of clinical care and research in hydrocephalus and CSF disorders, and thereby promote the best possible care for patients with these disorders. You are encouraged to join the Society to promote international exchanges, worldwide representation, and stimulating research and debate.

Mission Statement

Traditionally, hydrocephalus has been the “Aschenputtel” of Neurosurgery. The old school of investigators created a wide corpus of knowledge, often not formalized or synthesized in the peer-reviewed literature. Much has been reported in various international meetings, where the main mission may not have been hydrocephalus and related CSF disorders.

Since 2001, more focused meetings have been held, and it is now appreciated that a consistent international scientific assembly and forum is required to bridge between the junior and senior, and the clinical and basic scientists interested in this fascinating and multidisciplinary field to the potential benefit of patients and families.

We suggest that a new society whose mission is the pursuit of both clinical and basic research of the CSF circulation and its related disorders would be complementary to the existing societies, which are more clinically-oriented. On behalf of our colleagues worldwide, we are honored to propose that the new society should be called the INTERNATIONAL SOCIETY FOR HYDROCEPHALUS AND CEREBROSPINAL FLUID DISORDERS with the following aims: Promoting international exchanges and encouraging worldwide representation and stimulating research and debate. Providing and promoting excellence in professional education and research by offering a variety of programs in both the clinical aspects of hydrocephalus and the basic sciences to physicians, young researchers and allied health professionals. Supporting and advocating an environment which ensures ethical, high quality, care for hydrocephalus both in the developed and developing world by advancing public education and awareness. Supporting guidelines, standardized methods and ethically conducted clinical and basic research in the hydrocephalus, CSF disorders and related fields

International Society for Hydrocephalus and Cerebrospinal Fluid Disorders. February 27, 2008.

8 Membership Fees

Full Membership: Euro 100 Senior Membership: Euro 75 Junior Membership fee or Supporting Membership: Euro 50 Membership of the ISHCSF is included in the cost of registration for the ISHCSF annual meeting.

ISHCSF Executive Board Members

Michael A. Williams, MD, President Laurence Watkins, President-elect Daniele Rigamonti, Secretary-Treasurer Petra Klinge, Immediate Past-President Uwe Kehler – Chair of Scientific Committee

Gunes Aygok - Board Director Marianne Juhler - Board Director Etsuro Mori - Board Director

9 Registration Times

TIME DAY LOCATION

18.00 - 19.00 Thursday The Marriott (for IHIWG meeting)

6.45 - 17.30 Friday Wills Memorial Building

18.00 - 20.00 Friday The Marriott

6.45 - 18.00 Saturday Wills Memorial Building

6.45 - 18.00 Sunday Wills Memorial Building

6.45 - 18.00 Sunday Wills Memorial Building

Useful Information

TIME ZONES The official time zone is GMT (London).

LANGUAGE The language spoken in the United Kingdom is English.

WHAT TO WEAR Weather in Bristol is typically mild at this time of year with temperatures in early September around 20°C during the day and around 13°C at night. There will be a moderate chance of rain during the course of the meeting.

ELECTRICITY / VOLTAGE UK appliances are fitted with three-pin plugs that can be connected to the UK mains supply through wall sockets. Unlike the sockets in many other countries, these have a switch to turn the power supply on and off – make sure you’ve turned it on if you’re trying to charge your appliance.

10 UK power sockets deliver an average voltage of 230v although in practice this can be slightly higher.

To charge devices that are compatible with this voltage, simply buy the appropriate adapter from the airport or from high street shops such as Argos. If your device runs on a lower voltage, however, then you will also need a converter to stop it from over-heating. Even if your country uses lower voltages, remember to check whether your device is dual-voltage (look for the 110-240v notation) before buying a converter.

TELECOMMUNICATIONS The UK has an excellent telecommunications system. Pay phones are available across the city and are phone card operated. Bristol has comprehensive cellphone coverage. The International Direct Dial (IDD) code for the UK is +44.

CURRENCY The UK monetary unit is the pound ( ). Exchange rates are available in every daily newspaper and online. Cash and traveller’s cheques can be exchanged in most banks, currency exchange houses and hotels.

CREDIT CARDS Visa, MasterCard, and American Express are accepted in almost all commercial facilities.

SPORT ACTIVITIES Tennis courts can be made available on request: please contact the secretariat.

TOURS AND EXCURSIONS Tours for accompanying persons and delegates wishing to explore Bristol and the surrounding area outside the conference can be arranged separately through the Secretariat.

SAFE TRAVEL IN BRISTOL Bristol is an extremely safe city to travel in with a very low violent crime rate. The city centre is safe for pedestrian travel. Only use taxis or registered minicabs. Try to avoid walking alone at night. Keep to well-lit main roads.

Beware of wearing headphones – they reduce awareness of your surroundings.

In the UK, cars drive on the left. To ensure you cross roads safely, only use designated crossings, only cross when the green man is showing and take note of the signs indicating “look right” or “look left” to spot any oncoming traffic

USEFUL CONTACTS Emergency Services (police, ambulance, fire department) on 999 or 112. These numbers are free to call – only use them in a real emergency. To report non-urgent crime, contact your local police station by calling 101 from within the UK.

11 Social Programme

Welcome Reception

A welcome reception will be held from 7.00pm – 9.00pm in the Palm Court of The Bristol Marriott Royal Hotel. Drinks & a light buffet supper will be provided and will include an opportunity to taste traditionally brewed English Beers.

Gala Dinner

The Gala Dinner will be held on Sunday Evening at the Bristol Marriott Royal Hotel. The Champagne reception will start at 7.30pm, the Gala Dinner at 8.00pm.

Visiting Bristol & the surrounding area

A variety of tours and excursions can be booked separately via the conference secretariat. Places are limited and must be booked in advance.

Tour 1 Stonehenge and Wells

For centuries Stonehenge has remained an enigma, attracting countless fanciful theories to explain its mysterious origins. Discover and enter into the legend of this incredibly prehistoric monument built from 3000 BC to 2000 BC.

We also will stop at Wells to give you the opportunity to visit Wells cathedral, one of the most impressive cathedrals of England. Built between 1180 and 1306, Wells Cathedral survives with all of the original buildings associated with the cathedral including the Vicar’s Close, the Chapter House and Cloisters.

Then you will appreciate the beauty of the Bishop Palace, a stunning medieval Palace dating from the early-thirteenth century.

12 Tour 2 Leisurely Costwolds Tour

The Cotswolds – “the most English and the least spoiled of all our countrysides” J.B. Priestley

The Cotswolds, situated to the north and east of Bristol, is a unique region of the UK. Your travel in England would not be complete without a visit to the Cotswolds. The area is known for a rich unique history and culture and the natural beauty of the horizons: gentle hillsides, out-standing countryside with river valleys, water meadows and beech woods.

The Costwolds is also known for their historic villages and towns. You will appreciate the beauty of limestone villages, rolling wolds countryside, beautiful gardens and magnificent historic castles and stately homes.

Your route: Stow-on-the-Wold, Chipping Norton and Chipping Camden.

Tour 3 A day in Bath

Located just a few miles from Bristol, is the beautiful, and creative City of Bath. Full of culture, Bath was the only place in the UK to have the whole city designated as a World Heritage Site , in 1987. The city has an abundance of theatres, museums and other cultural attractions, which is why more than 3.8 million people from far and wide visit every year.

Bath is also the only place in the UK where you can relax naturally in hot spa water. The city, previously named in latin Aquae Sulis (“the waters of Sulis”) in AD 43, is rich in history. 20 years after the Romans had arrived in Britain, they built baths and a temple in the valley of the River Avon. Much later, it became popular as a spa town during the Georgian era. You can now admire the large heritage of Georgian architecture.

You will enjoy a tour at the Roman Bath and have a free time to discover all beauties of Bath or to relax at the Thermae Bath Spa.

13 Exhibitor’s Hall

Map & Floorplan In Any Event UK Wills Memorial Building, Bristol ISHCSF Annual Congress 2014 September 2014

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DIGITAL POSTER SCREENS TEA & TEA & COFFEE COFFEE KARL STORZ KARL

PLASMA RELAY SCREEN

BRAINLAB INTEGRA BK MEDICAL LIKVOR

FIRE EXIT In Any Event UK Wills Memorial Building, Bristol RECEPTION ROOM (Exhibition Area) Version 4 ISHCSF Annual Congress 2014 September© 2014 2014 Alexander Ball Productions Ltd

PLASMA PLASMA

CODMAN

RENISHAW TEA & TEA & COFFEE TEA & COFFEE COFFEE

BBRAUN (AESCULAP) BBRAUN MEDTRONIC

GRAND HALL (Exhibition Area) Version 4 © 2014 Alexander Ball Productions Ltd

14 Floorplan

Will’s Building

Satellite Meeting Room

Exhibitor’s Hall

15 Fannin (UK) Limited are proud to be sponsors of The Trainee’s Hydrocephalus Society.

We look forward to the inaugural meeting at Wills Memorial Building of Bristol University.

Visit us in the Reception Room where we will have our comprehensive and trusted CSF Management range along with our newest, exciting and innovative product!

www.fannin.eu Faculty

Session Chairs

William G Bradley Sam Browd Harold Rekate Marek Czosnyka Paul Chumas Marianne Juhler Kenichi Nishiyama Pat McAllister Uwe Kehler Anders Eklund John Kestle Carsten Wikkelso Etsuro Mori Graham Fieggen Michael A. Williams, MD Richard Edwards Jonathan Clark Jay Riva-Cambrin Laurence Watkins Jan Malm Masakazu Miyajima Etsuro Mori Guirish Solanki John Pickard Mark Luciano Masatsune Ishikawa Vartan Kurtcuoglu Mark Hamilton Marcus Bradley

Scientific Committee, Hydrocephalus 2014

Michael A. Williams, MD USA Carsten Wikkelso Sweden John MacGregor USA Babar Kahlon Sweden Jay Riva-Cambrin USA Anders Eklund Sweden Daniele Rigamonti USA Shinya Yamada Japan Ari Blitz USA Masakazu Miyajima Japan Harold Rekate USA Kenich Nishiyama Japan Richard Edwards UK Etsuro Mori Japan Zofia Czosnyka UK Uwe Keheler Germany Marek Czosnyka UK Ulrich-Wilhelm Thomale Germany Laurence Watkins UK Marianne Juhler Denmark Jan Malm Sweden Mark Hamilton Canada

17 Faculty: Invited Speakers

Ari Blitz

Dr. Blitz is the lead neuroradiologist for hydrocephalus and CSF disorders at the Johns Hopkins Medical Institutions. He is a graduate of Brown University and Brown University School of Medicine. As a Howard Hughes Medical Institute-National Institutes of Health Cloister scholar he performed research in electrophysiology under the tutelage of Dr. Michael Goldberg. Ari performed his internship at Harvard’s Beth Israel Deaconess Hospital then residency in radiology and fellowship in neuroradiology at Johns Hopkins Hospital.

Makoto Sasaki

Dr. Makoto Sasaki received his M.D. and Ph.D. from Iwate Medical University, Japan. After a 20-year career as a neuroradiologist there, he was appointed as Professor in the Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University. He has more than 200 publications and has received several awards including Cum Laude at RSNA 2001. He is mainly focused on research in neuroimaging for stroke, neurodegenerative disorders, psychiatric disorders, and idiopathic normal-pressure hydrocephalus.

Philippe Decq

Neurosurgeon, Professor and Head of the neurosurgical department of Beaujon Hospital in Paris.President of the hydrocephalus section of the French society of neurosurgery. He was President of the 2007 World Congress of Neuro- Endoscopy.

Abhaya Kulkarni

Dr. Kulkarni is a pediatric neurosurgeon and Professor of Surgery at the Hospital for Sick Children, Toronto and Program Director for the Neurosurgery Residency Program at the University of Toronto. Dr. Kulkarni’s research focuses on health outcome assessments in pediatric neurosurgery, with special emphasis on hydrocephalus. He is a site investigator for the North American Hydrocephalus Clinical Research Network and serves on the editorial boards of Neurosurgery and the Journal of Neurosurgery Pediatrics.

Jonathan Clark - Keynote Speaker

Jonathan Clark is an Associate Professor of Neurology and Space Medicine at Baylor College of Medicine and teaches at the Center for Space Medicine (CSM). Dr. Clark was a NASA Space Shuttle Crew Surgeon, Medical Director of the Red Bull Stratos Project, Chief Medical Officer for Excalibur Almaz, and is Chief Medical Officer for the Inspiration Mars Foundation. His professional interests focus on the neurologic effects of extreme environments.

16 Robert Marchbanks

Consultant Clinical Scientist and Director of the Non-invasive Intracranial Pressure Assessment (NIPA) Unit, Southampton. Past Clinical Director of Audiological Science, Royal National Throat, Nose and Ear Hospital, London. Honorary Senior Research Fellow Southampton University. Managing Director of Marchbanks Measurement Systems Ltd, Southampton University spin-out and provider of CCFP Flight units for the NASA Visual Impairment – Intracranial Pressure Project, Johnson Space Center.

James P. McAllister

James P. “Pat” McAllister II, PhD is Professor, Department of Neurosurgery at Washington University School of Medicine in St. Louis. He received his PhD from Purdue University in 1976 and held faculty positions at UCLA, Temple University, Cleveland Clinic Foundation, Wayne State University, and the University of Utah. Dr. McAllister studies all aspects of the pathophysiology of hydrocephalus and received the 2005 Robert H. Pudenz Prize for Excellence in Cerebrospinal Fluid Physiology and Hydrocephalus.

Conor Mallucci

Conor Mallucci is a paediatric Neurosurgeon working in Liverpool since 1998, currently clinical lead and clinical director of the North West paediatric neuroscience network. He has published 107 articles in the peer-reviewed literature, edited an International textbook on CSF disorders and has a major interest in Hydrocephalus and Neuro-oncology research. Currently chairman of the BPNG research group and Chief Investigator for the UK multicentre randomised BASICS trial looking at prevention of VP shunt infection.

Jay Riva-Cambrin

Dr. Riva-Cambrin is an Associate Professor of pediatric neurosurgery at the University of Utah in Salt Lake City. He completed his neurosurgical residency at the University of Toronto in 2005 and completed a fellowship at the Hospital for Sick Children in Toronto in 2006. He has a Masters in clinical epidemiology and is has an active research interest in pediatric hydrocephalus. He is a Principal Investigator (PI) within the Hydrocephalus Clinical Research Network (HCRN).

Ingolf Sack

Ingolf Sack is a Heisenberg professor of the German Research Foundation for Experimental Radiology and Elastography at Charité – Universitätsmedizin Berlin. His research activities span from NMR spectroscopy, MRI, biomechanics, acoustics and rheology to medical ultrasound, signal processing and image analysis. He leads an interdisciplinary team of physicists, engineers, chemists and physicians which has pioneered pivotal developments in Elastography of the liver, muscle, heart and brain.

19 John Kestle - Keynote Speaker

John Kestle trained in neurosurgery in Toronto (1984-92) and Clinical Epidemiology at McMaster University. After 6 years at the University of British Columbia he moved to the University of Utah and served as Residency Program Director and Chief of Pediatric Neurosurgery. He is currently Chair of the Editorial Board of the Journal of Neurosurgery Pediatrics, Chair of the Hydrocephalus Clinical Research Network and Professor and Vice Chair, Clinical Research for the Department of Neurosurgery at the University of Utah.

James Drake

Dr. Drake’s primary research and clinical interests relate to engineering applications to neurosurgery including hydrocephalus, image guided surgery and robotics. This encompasses the main themes of CIGITI which are broadened to include applications of imaging, robotics and simulation for all paediatric surgical disciplines. Dr. Drake has over 230 peer-reviewed publications, holds major grants from CIHR/NSERC and Brain Canada. His clinical interests relate to the investigation and management of hydrocephalus including the use of endoscopy, image guided surgery for brain tumours and epilepsy, and the management of complex spinal disorders.

Rashid Deane

Rashid Deane, professor in the Department of Neurosurgery at the University of Rochester (NY, USA), has been a faculty there since 2002. He completes his PhD at St Thomas’s Hospital Medical School and a postdoctoral fellowship at Kings College London. Before joining the University of Rochester he was a Reader in Physiology. His research interest includes the clearance of molecules from brain via the CSF/ISF flow, brain vascular barriers (BBB and choroid plexus) and the neurovascular unit in health and disease with a focus on neurodegeneration (e.g., Alzheimer’s disease), and the transport of molecules into brain.

Marios Papadopoulos

Marios Papadopoulos is a Professor of Neurosurgery at St George’s, University of London. He graduated from the Universities of Cambridge and Oxford and trained in Neurosurgery in London and the University of California at San Francisco. His research interests are aquaporins (AQPs), which are water channel proteins. His work in this field spans 14 years and has revealed multiple roles for AQPs such as controlling the flow of water into and out of the brain and spinal cord (AQP4), cerebrospinal fluid formation (AQP1) and absorption (AQP4), astrocyte cell migration and reactive gliosis (AQP4) and others [1]. Patients who have circulating antibodies against AQP4 develop the inflammatory demyelinating disease neuromyelitis optica [2]. Prof. Papadopoulos’ clinical interests are complex spinal surgery and vascular neurosurgery.

Martin Schuhmann

Prof. Martin U. Schuhmann is Chief of Pediatric Neurosurgery, Department of Neurosurgery at University of Tübingen, Germany. In addition he is heading the Adult Hydrocephalus Programm. He currently serves as Speaker of the Research Section of Intracranial Pressure, Cerebral Blood Flow and Hydrocephalus of the German Society of Neurosurgery. One of his various research interests is ICP analysis and multimodal monitoring in various types of brain pathology.

20 Ann Logan

Ann Logan is Professor of Molecular Neuroscience and Head of the Neurobiology Department at the University of Birmingham. She has generated more than 150 research publications on the role of growth factors in injury responses of the brain, eye and spinal cord. Ann also leads the Regenerative and Reconstructive Medicine research team in the NIHR Surgical Reconstruction and Microbiology Research Centre at the Queen Elizabeth Hospital Birmingham.

Hannah Botfield

Hannah Botfield is a research fellow working with Prof Logan in the CSF Disorders research programme.

Dominic Wilkinson

Dominic Wilkinson is a physician specialising in newborn intensive care and medical ethics. He is Director of medical ethics at the Oxford Uehiro Centre for Practical Ethics and consultant neonatologist at the John Radcliffe Hospital, Oxford. He is the author of “Death or Disability: the ‘Carmentis Machine’ and decision-making for critically ill children” (OUP 2013)

Carsten Wikkelso

Carsten Wikkelso’s main research focuses have been diagnostic, pathophysiological and therapeutic aspects on CSF related disorders especially hydrocephalus and degenerative CNS disorders. The methods of interest have been MR imaging, CSF dynamic and chemistry and CBF besides basic clinical methods.

Shinya Yamada

Chief of Neurosurgery at Toshiba Rinkan Hospital, Japan. CSF-ISF physiology: Trained in the physiology and biophysics laboratory at Brown University. 1988–1990. Research Director of Neurosurgery at Children’s Hospital Los Angeles (CHLA), Keck University of Southern California 2000–2003. Collaborative research with CHLA Neurosurgery 2003–.

21 IHIWG

The International Hydrocephalus Imaging Working Group (IHIWG)

The IHIWG is affiliated to the ISHCSF. The group meets in the spring (at the ASNR) and fall (at the ISHCSF) every year. We encourage ISHCSF members to with an interest in hydrocephalus imaging to support this group. This fall’s meeting is to be held on Friday the 5th of September. An IHIWG dinner is being held on Thursday 4th September.

Role of the IHIWG

The role of the International Hydrocephalus Imaging Working Group is to facilitate the interactions of neuroscientists, neuroradiologists an MRI engineers and physicists to educate each other on what is possible with this wonderful new tool to study hydrocephalus and related disorders in non-invasive ways. Unfortunately we do not speak a common language when dealing with MRI and hydrocephalus. We do not understand the challenges faced in each of these fields. The ultimate goal will be to utilize the expertise of all stakeholders to plan relevant studies of pathophysiology and treatment of hydrocephalus and related disorders. (Harold Rekate).

Mission Aims of the IHIWG

• Hold international meetings expanded by virtual meeting using new meeting technology

• Identify leaders who have the skill set and energy to work with others in searching for answers, developing protocols, and assisting the other members in structuring their research.

• Facilitate cooperative endeavors among basic scientists, engineers and clinicians so that propinquity diminishes as a barrier to advancement.

• Organize monthly “journal clubs” where articles are sent out to all members leading to a discussion and explanation to the uninitiated.

22 IHIWG Sessions

Programme

Friday 5th September

TIME TITLE SPEAKER SESSION/DETAILS

7.00 - 8.00 Continental Breakfast

8.00 - 8.05 Montreal IHIWG meeting re-­cap/Bristol introduction Harold Rekate Session: 1 Elastography 8.05 - 8.25 Clinical application of MR elastography NicholasWetjen Chair: Harold Rekate 8.30 - 8.50 Brain Elastography during jugular compression - insights Lynne Bilston for SILPAH? 9.00 - 9.20 Syndrome of unexpectedly low ICP Mark Hamilton 9.30 - 9.50 Cerebral MR elastography- - preclinical and clinical Katharina Schregel applications

10.00 - 10.20 Coffee Break

10.30 - 10.50 Resting-state activity in Hydrocephalus David Limbrick Session 2: Connectivity & Misc. 11.00 - 11.20 DTI applied to Chiari and Acrondroplasia Andrea Poretti Chair: Daniele Rigamonti 11.30 - 11.50 History of hydrocelphalus Imaging David Solomon

12.00 - 13.00 Lunch

13.00 - 13.20 Periarterial drainage of ISF from the brain Roxanne Carrare Session 3: Fluid driving mechanisms 13.30 - 13.50 CSF driving mechanisms in the ventricles Vartan Kurtcuoglu Chair: Vartan Kurtcuoglu 14.00 - 14.20 PC MRI quantification of CSF dynamics William Bradley 14.30 - 14.50 CSF movement: the importance of scale Harold Rekate

15.00 - 15.20 Coffee Break

15.30 - 15.50 In vitro comparison of 4D and 2D PC MRI assessment Vartan Kurtcuoglu Session 4: Diagnostics of CSF dynamics Chair: Bryn Martin 16.00 - 16.20 2D PC MRI CSF flow assessment in Chiari Rajiv Bapuraj 16.30 - 16.50 Critical closing pressure in hydrocephalus Marek Czosnyka 17.00 - 17.20 ICP and body position in hydrocephalus Anders Eklund

Saturday 6th September

TIME TITLE SPEAKER SESSION/DETAILS

7.00 - 8.00 Continental Breakfast

8.00 - 9.50 Hal and Bill Chair ISHCSFD Neuroradiology ISHCSFD Neuroradiology session (separate from IHIWG) Chairs: William Bradley and Harold Rekate

10.00 - 10.20 Coffee Break

10.30 - 10.50 Slit ventricle syndrome Grant Bateman Session 5: Diagnostics 11.00 - 11.20 CT segmentation/volumetrics Robin Holmes Chair: Harold Rekate 11.30 - 11.50 DESH for detection of NPH Shinya Yamada

11.50 - 13.45 Young Investigators Joint ISHCSFD/IHIWG session

23 Special Session

In collaboration with the Baylor College of Medicine Center for Space Medicine: Visual Impairment/Intracranial Pressure (VIIP) in Spaceflight

Session Chairs: Jon Clark & Michael A. Williams

This session follows on from last year’s successful session in which Dr Christian Otto, Lead Scientist, NASA Visual Impairment Intracranial Pressure Risk group, introduced the Society to the problem of VIIP in long-duration space flight. VIIP is characterized by many, though not all, of the features of idiopathic intracranial hypertension, including visual impairment, papilledema and moderate elevation of CSF pressure when measured by lumbar puncture after return to earth. VIIP is considered one of NASA’s top health concerns, as impairment of an astronaut’s vision on a long-duration exploration mission could compromise the astronaut’s health and put mission safety at risk.

Over the last 12 months members of the ISHCSF, in collaboration with the Baylor Center for Space Medicine, have been working towards a better understanding of VIIP and how it may impact on plans for prolonged space flight missions, including a manned Mars “fly-by” mission.

Our Keynote Speaker for this Session, Jon Clark, MD, MPH (Baylor College of Medicine Center for Space Medicine; Baylor College of Medicine Department of Neurology; Space Medicine Advisor, National Space Biomedical Research Institute; Medical Director of the Red Bull Stratos Mission; Former NASA Flight Surgeon; Chief Medical Officer, Inspiration Mars Foundation) will discuss the possible health and safety challenges associated with getting humans to Mars.

A key challenge of VIIP is that the underlying pathophysiology has yet to be proven. One of the leading hypotheses is elevated ICP resulting from fluid shifts from the lower body toward the head in the zero gravity environment. Integral to the understanding of this is the ability to measure ICP in space. Robert Marchbanks will outline the challenges of measuring ICP in a zero gravity environment. Any such research would involve non-invasive techniques, and Jan Malm and Anders Eklund will discuss the requirements for validation of candidate methods. Michael A. Williams, who is principal investigator of a research project funded by the National Space Biomedical Research Institute (NSBRI), will offer an overview of VIIP, a critique of the ICP hypothesis, and recommendations for future research. The free paper session will include further papers on VIIP.

The Baylor College of Medicine Center for Space Medicine The Center for Space Medicine (CSM) was established at Baylor College of Medicine in 2008 and is a collaborative enterprise involving multiple Baylor College of Medicine departments and centers, the NSBRI, NASA, Rice University, Texas Medical Center institutions, and other academic, industry and government organizations nationally and internationally. The CSM is recognised as a world academic leader in space biomedical research and education, and in translating the advances in knowledge and technology to benefit life on Earth.

24

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neuro | surgical tooling* neuro | administration sets*

Working towards delivering advanced engineering solutions to stereotactic neurosurgery

Visit us at our stand in the Grand Hall and sign-up for our Factory visit on Monday 8th September

www.renishaw.com

* not currently available for clinical use Sponsored Sessions

Renishaw factory tour: Monday 8th September, leaving the Bristol Marriot Royal Hotel at 7:45am and returning at 10:30am.

Renishaw is a global company with core skills in measurement, motion control, 3D printing, spectroscopy, medical devices and precision machining. We are applying cutting-edge precision engineering technology to the challenges of neurosurgery. The neuromate® surgical robot is a central element of this strategy. It provides a flexible, yet highly repeatable platform for precision neurosurgery including robotic neuroendoscopy.

Fannin Saturday am breakfast seminar: 07:00am - 08:00am: The breakfast seminar will be used to introduce a product we are about to launch here in the UK, LiquoGuard. LiquoGuard® is a revolutionary step in cerebrospinal fluid management, being the only CSF management system in the world that drains and simultaneously measures CSF pressure. The Liquoguard system controls the drainage rate and can sound various alarms if there‘s a change in the patients condition. Alternative uses for the LiquoGuard system include NPH diagnosis, external shunt testing and determining the correct operating pressure for an internal shunt system. Stefan Lang, the International Product Manager for LiquiGuard, will be running the session which will invlove a powerpoint presentation and a practical hands on session.

Trainees Hydrocephalus Society (UK) Fannin: 18.00 - 19.00: The inaugural meeting of the Trainees Hydrocephalus Society will run as a satellite meeting alongside the main program. It’s been designed for UK trainees to help provide extensive education into Hydrocephalus. The agenda will be set by the society’s president, Kevin Tsang from Bristol.

BBraun Lunchtime symposium: 12:35 - 1:30 - Miethke proGAV 2.0 - Gravitational valve (r)evolution Research Session

BASICS Trail (UK) Investigators Meeting 11:30 – 13:30 Monday 8th September. Chaired by Conor Mallucci

26 NPH Educational Symposium

Timetable

Friday 5th September

TIME TITLE SPEAKER DETAILS

8.30 - 10.00 Tea & Coffee

10.00 - 10.05 Welcome

10.05 - 10.30 Introduction to Normal Pressure Hydrocephalus Daniele Rigamonti Historical perspective. The NPH triad. Classification of NPH. Causes of secondary NPH. Idiopathic NPH.

10.30 - 11.00 Idiopathic Normal Pressure Hydrocephalus Carsten Wikkelso Clinical history and examination findings in (iNPH): Clinical Features iNPH.

11.00 - 11.45 Neuroradiology of idiopathic Normal Pressure Ari Blitz Overview of radiological investigations; Hydrocephalus key radiological features; advanced MRI investigations. DESH.

11.45 - 12.00 Neuropathology of idiopathic Normal Pressure Richard Edwards Key neuropathological correlates; co- Hydrocephalus morbidities.

12.00 - 12.30 Treatment of iNPH Richard Edwards How shunts work. Shunt valve mechanisms including programmable valves. Shunt selection. Is there a role for endoscopic third ventriculostomy in NPH?

12.30 - 13.15 Lunch

13.15 - 13.45 Epidemiology and Natural History of iNPH Carsten Wikkelso Estimated disease incidence from population studies. Natural history and clinical progression of iNPH.

13.45 - 14.15 Basic CSF Dynamics & Supplementary Testing Anders Eklund Lumbar CSF infusion studies, what are they, in NPH what do they measure. Extended lumbar CSF drainage vs “tap testing”.

14.15 - 14.45 CSF Biomarkers in iNPH Laurence Watkins Differentiation of NPH from other conditions. Identification of co-morbidities.

14.45 - 15.15 Break

15.15 - 15.45 Complications following Treatment of iNPH Mark Hamilton Risk factors for shunt related complications; complications of CSF shunting and their avoidance. Surveillance of patients with programmable valves.

15.45 - 16.10 Health Economics of iNPH Michael A. Williams, MD How big is the problem, is it cost effective to treat?

16.10 - 16.35 NPH Grading scales and their use in evaluating Masatsune Ishikawa Grading of NPH severity; Impact of the disease the Impact of CSF shunting on both patients and and it’s treatment on caregivers on the Caregiver burden

16.35 - 17.00 Shunt surgery for iNPH in extreme old age or in Gunes Aygok Are there subgroups who may not benefit from patients with advanced symptoms treatment? Likelihood of shunt responsiveness in advanced age or in severe disease states.

17.00 - 17.30 EXPERT PANEL ROUND TABLE Q & A SESSION ON iNPH

17.30 MEETING CLOSE

This Educational Symposium was supported by an Educational Grant from Codman Neuro. It has been accredited by the Royal College of Surgeons of England for up to 6 CMCME/CPD points

27 Overview of Scientific Programme

Saturday 6th September

TIME TITLE SPEAKER

8:00 - 8:05 Welcome

8.00 - 10.00 Session 1: Neuroradiology I Chairs: William G Bradley, Harold Rekate 8:05 - 8:30 High resolution & 3D MRI in the evaluation of CSF disorders Ari Blitz (USA) 8:30 - 8:55 Can ultrahigh-field MRI identify shunt responders in iNPH? Makoto Sasaki (Japan) 8:55 - 9:55 Free Papers

9.55 - 10.15 BREAK & POSTER VIEWING

10.15 - 11.55 Session 2: Neuroendoscopy Chairs: Paul Chumas, Kenichi Nishiyama 10.15 - 10.40 Robotic Neuroendoscopy Philippe Decq (France) 10.40 - 11.05 Multicentre, international studies in endoscopy: lessons learned and the way forward Abhaya Kulkarni (Canada) 11.05 - 11.55 Free Papers

11.55 - 13.40 Session 3 - Lunchtime Symposium : Young Investigators Award Chairs/Judges: Uwe Kehler, John Kestle, Etsuro Mori

13.40 - 16.35 Session 4: SPECIAL SESSION on Idiopathic Intracranial Hypertension and Visual Impairment due to Intracranial Pressure (VIIP) in Spaceflight Chairs: Michael Williams, Jonathon Clark 13.40 - 14.15 Getting Humans to Mars: Health & Safety Challenges Jonathan Clark (USA) 14.15 - 14.40 The challenges of non-invasive measurement of intracranial pressure in a zero Robert Marchbanks (UK) gravity environment 14.40 - 14:55 Validation of non-invasive ICP methods Jan Malm & Anders Eklund 14:55 - 15:10 A review and critique of the ICP hypothesis of Visual Impairment/Intracranial Pressure Michael A. Williams, MD (VIIP)

15:10 - 15:15 Announcement of Winner Of Young Investigators Award

15.15 - 15.35 BREAK & POSTER VIEWING

15.35 - 16.35 Free Papers VIIP/IIH

16.35 - 18.00 Session 5: Supplementary Testing in Hydrocephalus Chairs: Laurence Watkins, Masakazu Miyajima 16:35 - 17:00 CSF Biomarkers to Predict outcome in Post-haemorrhagic hydrocephalus James P. McAllister (USA) 17.00 -18.00 Free Papers

18.00 -19.00 Satellite Session: Trainees Hydrocephalus Society (UK) (Sponsored by Fannin)

Sunday 7th September

TIME TITLE SPEAKER

8.00 - 9.40 Session 6: Pediatric Hydrocephalus I Chairs: Guirish Solanki, Mark Luciano 8:00 - 8.30 The BASICS Trial Conor Mallucci (UK) 8.30 - 9.00 System changes to reduce shunt infection Jay Riva-Cambrin (USA) 9.00 - 9.40 Free Papers

9.40 - 10.00 BREAK + POSTER VIEWING

28 TIME TITLE SPEAKER

10.00 - 11.50 Session 7: Neuroradiology II Chairs: Marcus Bradley, Vartan Kurtcuoglu 10:00 - 10:30 MR Elastography in the evaluation of Hydrocephalus Ingolf Sack (Germany) 10.30 - 11.50 Free Papers

11.50 - 12.05 Society Notices: John Pickard - An Appreciation Marek Czosnkya

12.05 - 12.20 In Memorium

12.20 - 13.00 Keynote Guest Lecture (Anthony Marmarou Memorial Lecture): Randomised trials in pediatric hydrocephalus: the past, the present and the future John Kestle (USA)

13.00 - 13.40 LUNCH + POSTER VIEWING

13.40 - 15.10 Session 8: Shunt Hardware Design Chairs: Sam Browd, Marek Czosnyka 13:40 - 14:10 Shunt valve design: simplicity or complexity? James Drake (Canada) 14.10 - 15.10 Free Papers

15.10 - 15.30 BREAK + POSTER VIEWING

15.30 - 17.30 Session 9: Experimental Hydrocephalus Chairs: Marianne Juhler, Pat McAllister 15:30 - 16:00 Glymphatics: A new Paradigm For CSF Circulation Rashid Deane (USA) 16:00 - 16:30 The role of Aquaporins in Brain water balance Marios Papadopoulos (UK) 16.30 - 17.30 Free Papers

17.30 - 17.45 Presidential Address

17.45 - 18.30 ISHCSF BUSINESS MEETING

Monday 8th September

TIME TITLE SPEAKER

8.00 - 9.40 Session 10: CSF Dynamics Chairs: Anders Eklund, Carsten Wikkelso 8:00 - 8:30 Assessment of apparent arrested hydrocephalus: to shunt or not to shunt Martin Schuhmann (Germany) 8.30 - 9.50 Free Papers

9.50 - 10.10 BREAK + POSTER VIEWING

10.10 - 10.50 Session 11: Clinical trials in Hydrocephalus Chairs: Jay Riva-Cambrin, Jan Malm

10.50 - 12.40 Session 12: Pediatric Hydrocephalus II Chairs: Graham Fieggen, Richard Edwards 10.50 - 11.15 Drug Treatment of Infantile Hydrocephalus Ann Logan & Hannah Botfield (UK) 11.15 - 11.45 Ethical considerations in the treatment of severe congenital hydrocephalus Dominic Wilkinson (UK) 11.45 - 12.35 Free Papers

11.30 - 13.30 BASICS Trail (UK) Investigators Meeting

12.35 - 13.30 Sponsored Lunchtime Seminar: B Braun

13.30 - 15.45 Session 13: Normal Pressure Hydrocephalus Chairs: Etsuro Mori, John Pickard 13.30 - 13.55 Programmable valve setting in Adult Hydrocephalus Carsten Wikkelso (Sweden) 13.55 - 15.05 Free Papers 15.05 - 15.45 Flash presentations

15.45 - 16.05 BREAK + POSTER VIEWING

16.05 - 17.25 Session 14: Adult Hydrocephalus Chairs: Masatsune Ishikawa, Mark Hamilton 16.05 - 16.30 Mapping cerebrospinal fluid movement using magnetic resonance spin labelling Shinya Yamada (Japan) in complex hydrocephalus 16.30 - 17.20 Free Papers

17.20 - 17.30 Meeting Closing Remarks

29 Detailed Programme

Saturday 6th September NEURORADIOLOGY I Chairs William G Bradley

Harold Rekate

08:05 – 08:30 High resolution & 3D MRI in the evaluation of CSF disorders Ari Blitz (USA) 08:30 – 08:55 Can ultrahigh-field MRI identify shunt responders in iNPH? Makoto Sasaki (Japan)

08:55 – 09:05 ABSTRACT NUMBER: 001 NARROWING OF HIGH CONVEXITY/MIDLINE SUBARACHNOID SPACES PREDICTS THE EFFECTIVENESS OF CEREBROSPINAL FLUID SHUNTING IN PATIENTS WITH NORMAL-PRESSURE HYDROCEPHALUS Tetsuro Ishihara, Wataru Narita, Toru Baba, Osamu Iizuka, Yoshiyuki Nishio, Minoru Matsuda, Etsuro Mori

Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

09:05 – 09:15 ABSTRACT NUMBER: 002 A COMPARISON OF THE DISPROPORTIONATELY ENLARGED SUBARACHNOID SPACE (DESH) PATTERN TO THE AQUEDUCTAL CSF STROKE VOLUME IN PATIENTS WITH CLINICAL NPH William Bradley, Abdulrahman Almutairi University of California, San Diego, San Diego, USA

09:15 – 09:25 ABSTRACT NUMBER: 003 RELATIONSHIP BETWEEN TEMPORAL CHANGES OF THE REGIONAL APPARENT DIFFUSION COEFFICIENT AND THE INTRACRANIAL COMPLIANCE IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Mitsuhito Mase1, Toshiaki Miyati2, Tomoshi Osawa1, Hiroshi Yamada1, Naoki Ohno2, Hirohito Kan3, Harumasa Kasai3, Kazuo Yamada1 1Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan 2Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 3Department of Radiology, Nagoya City University Hospital, Nagoya, Japan

09:25 – 09:35 ABSTRACT NUMBER: 004 CEREBRAL PERFUSION MEASURED WITH PCASL BEFORE AND REPEATEDLY AFTER CSF REMOVAL IN iNPH PATIENTS Johan Virhammar1, Katarina Laurell2, André Ahlgren,3 Kristina Cesarini1, Elna-Marie Larsson4

1Department of Neuroscience, Neurology, Uppsala University, Sweden 2Department of Pharmacology and Clinical Neuroscience, Neurology, Östersund, Umeå University, Sweden 3Department of Medical Radiation Physics, Lund University, Sweden 4Department of Radiology, Uppsala University, Sweden

30 09:35 – 09:45 ABSTRACT NUMBER: 005 DEVELOPMENT OF AUTOMATED SEGMENTATION OF X-RAY COMPUTED TOMOGRAPHY (CT) FOR THE DIAGNOSIS OF SHUNT-RESPONSIVE IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (iNPH) Robin Holmes1, Will Singleton2, Alex Mortimer3, Claire Doddy4, Richard Edwards2 1Medical Physics, University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom 2Department of Neurosurgery, North Bristol NHS Trust, Bristol, United Kingdom 3Department of Neuroradiology, North Bristol NHS Trust, United Kingdom 4Medical Physics, North Bristol NHS Trust, Bristol, United Kingdom

09:45 – 09:55 ABSTRACT NUMBER: 006 AMYLOID DEPOSITS AND RESPONSE TO SHUNT SURGERY IN IDIOPATHIC NORMAL-PRESSURE HYDROCEPHALUS Manabu Tashiro1, Nobuyuki Okamura1, Katsutoshi Furukawa,2 Hiroyuki Arai3, Ren Iwata3, Etsuro Mori4, Kazuhiko Yanai5

1Division of Cyclotron Nuclear Medicine, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan 2Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan 3Department of Geriatrics and Gerontology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan 4Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan 5 Division of Radiopharmaceutical Chemistry, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan

9.55- 10.15 BREAK & POSTER VIEWING

NEUROENDOSCOPY

Chairs Paul Chumas Kenichi Nishiyama 10:15 – 10:40 Robotic Neuroendoscopy Phillippe Decq (France) 10:40 – 11:05 Multicentre, international studies in endoscopy: lessons learned and the way forward Abhaya Kulkarni (Canada)

11:05 – 11:15 ABSTRACT NUMBER: 007 PRIMARY VS. SECONDARY ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) FOR OBSTRUCTIVE HYDROCEPHALUS Ignacio Jusue-Torres, Eric Sankey, Jamie Robison, Jan Wemmer, Rory Goodwin, Jamie Hoffberger, Ari Blitz, Daniele Rigamonti

John Hopkins Hospital, Baltimore, MA, USA

11:15 – 11:25 ABSTRACT NUMBER: 008 INTRACRANIAL NEUROENDOSCOPIC EXPERIENCE AND COMPLICATION RATES IN 273 ADULT AND PEDIATRIC PATIENTS: A POPULATION-BASED STUDY WITH LONG-TERM FOLLOW-UP Mark Hamilton, Roberto Diaz, Walter Hader, Fady Girgis University of Calgary, Calgary, Alberta, Canada

11:25 – 11:35 ABSTRACT NUMBER: 009 PAEDIATRIC ENDOSCOPIC THIRD VENTRICULOSTOMY - LONG TERM FOLLOW UP Matthew Stovell1, Michael Jenkinson2, Bassel Zebian1, Benedetta Pettorini1, Conor Mallucci1 1Alder Hey, Liverpool, United Kingdom 2Walton Centre, Liverpool, United Kingdom

31 11:35 – 11:45 ABSTRACT NUMBER: 010 ENDOSCOPIC THIRD VENTRICULOSTOMY ON TREATMENT OF SHUNT-INDUCED SLIT VENTRICLE SYNDROME Guo-Qiang Chen, Qing Xiao, Jia-ping Zheng Aviation General Hospital of China Medical University, Beijing, China

11:45 – 11:55 ABSTRACT NUMBER: 011 IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) OUTCOMES AFTER PRIMARY ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) Ignacio Jusue-Torres, Eric Sankey, Ari Blitz, Jamie Hoffberger, Daniele Rigamonti Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

YOUNG INVESTIGATORS AWARD Chairs/Judges Uwe Kehler John Kestle

Etsuro Mori

12:05 – 12:15 ABSTRACT NUMBER: 012 RELATIONSHIP BETWEEN FLEXION OF THE NECK AND CHANGES IN INTRACRANIAL PRESSURE Sarah Skovlunde Hornshøj, Morten Andresen, Alexander Lilja, Dorthe Christoffersen, Marianne Juhler

Neurokirurgisk klinik, NK 2092, Rigshospitalet, Copenhagen, Denmark

12:15 – 12:25 ABSTRACT NUMBER: 013 THE DISEASE STATE INDEX IN PREDICTION OF SHUNT SURGERY OUTCOME IN IDIOPATHIC NORMAL- PRESSURE HYDROCEPHALUS

Antti Luikku, Anette Hall, Maria Kojoukhova, Jussi Mattila, Jyrki Lötjönen, Juha Jääskeläinen, Ville Leinonen Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland

12:25 – 12:35 ABSTRACT NUMBER: 014 INTRACRANIAL PRESSURE IN HYDROCEPHALUS: IMPACT OF SHUNT ADJUSTMENTS AND BODY POSITIONS Dan Farahmand1, Sara Qvarlander2, Jan Malm3, Carsten Wikkelsö1, Anders Eklund2, Magnus Tisell1 1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Radiation Sciences, Umeå University, Sweden 3Department of Clinical Neuroscience, Umeå University, Sweden

12:35 – 12:45 ABSTRACT NUMBER: 015 EVANS INDEX AND SYMPTOMS OF NORMAL PRESSURE HYDROCEPHALUS - AN EPIDEMIOLOGICAL INVESTIGATION Daniel Jaraj1, Katrin Rabie1, Tom Marlow1, Christer Jensen2, Ingmar Skoog1, Carsten Wikkelsø1 1Institute of neuroscience and phyisiology, Gothenburg University, Gothenburg, Sweden 2Institute of clinical sciences, Gothenburg university, Gothenburg, Sweden

32 12:45 – 12:55 ABSTRACT NUMBER: 016 FEASIBILITY OF RADIOLOGICAL MARKERS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Maria Kojoukhova1, Anna Sutela2, Anne M Koivisto3, Jaana Rummukainen 4, Anne Remes5, Ritva Vanninen2, Juha E Jääskeläinen1, Ville Leinonen1, Irina Alafuzoff6, Hilkka Soininen3 1Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 2Department of Radiology, Kuopio University Hospital, Kuopio, Finland 3Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 4Department of Pathology, Kuopio University Hospital, Kuopio, Finland 5Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 6Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland and Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University and Department of Pathology and Cytology, Uppsala University Hospital. Kuopio, Finland

12.55 – 13.05 ABSTRACT NUMBER: 017 REFINING NON-INVASIVE TECHNIQUES TO MEASURE INTRACRANIAL PRESSURE: COMPARING EVOKED AND SPONTANEOUS TYMPANIC MEMBRANE DISPLACEMENTS Laurie Finch, Anthony Birch, Robert Marchbanks, Diederik Bulters University of Southampton, Southampton, United Kingdom

13.05 – 13:15 ABSTRACT NUMBER: 018 NATURAL COURSE OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Kerstin Andrén, Per Hellström, Carsten Wikkelsö, Magnus Tisell Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden

13:15 – 13:25 ABSTRACT NUMBER: 019 IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS AND VASCULAR RISK FACTORS - A POPULATION-BASED STUDY Simon Agerskov, Daniel Jaraj, Katrin Rabiei, Thomas Marlow, Christer Jensen, Ingmar Skoog, Carsten Wikkelsø Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden

13:25 – 13:35 ABSTRACT NUMBER: 020

2.4% OF MOUSE GENE KNOCKOUTS SHOW ENLARGED BRAIN VENTRICLES: A RESOURCE TO IDENTIFY GENES RELATED TO INFANTILE CONGENITAL HYDROCEPHALUS Helen Whitley1, Anna Mikhaleva2, Amélie Baud3, Valerie E. Vancollie4, Andrew Edwards1, Meghna Kannan5, Christel Wagner5, Anaïs Duret5, Isabel Herr2, Jeanne Estabel3, Christopher J. Lelliott3, Jacqueline K. White3, David J. Adams3, David A. Keays6, Jonathan Flint1, Yann Hérault5, Alexandre Reymond6, Binnaz Yalcin5

1Welcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford, United Kingdom 2Center for Integrative Genomics, University of Lausanne, Switzerland 3EMBL-European Bioinformatics Institute, Hinxton, Cambridge, United Kingdom 4Welcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom 5Institute of Genetics and Molecular and Cellular Biology, Illkirch, France 6Research Institute of Molecular Pathology, 1030 Vienna, Austria

33 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE Chairs: Mike Williams Jon Clark 13.40 – 14.15 Getting Humans to Mars: Health & Safety Challenges Jon Clark (USA) 14.15 – 14.40 The challenges of non-invasive measurement of intracranial pressure in a zero gravity environment Robert Marchbanks (UK) 14.40 – 14:55 Validation of methods of non-invasive ICP monitoring in space Jan Malm & Anders Eklund 14.55 – 15:10 A review and critique of the ICP hypothesis of Visual Impairment due to Intracranial Pressure (VIIP) Michael A. Williams, MD

15.10 – 15.15 ANNOUNCEMENT OF YOUNG INVESTIGATORS AWARD WINNER 15.15 - 15.35 BREAK & POSTER VIEWING

15:35 – 15:45 ABSTRACT NUMBER: 021 EFFECT OF INTRACRANIAL HYPERTENSION ON COGNITION: IMPLICATIONS FOR SPACE TRAVEL Abhay Moghekar, Daniele Rigamonti, David Solomon Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

15:45 – 15:55 ABSTRACT NUMBER: 022 THE OPTIC NERVE COMPARTMENT SYNDROME. DOES IT EXPLAIN PAPILLEDEMA IN ASTRONAUTS? Esriel Killer1, Neil Miller2, Luca Remonda1 1Kantonsspital Aarau Switzerland 2Wilmer Institute, Johns Hopkins, Baltimore USA

15:55 – 16:05 ABSTRACT NUMBER: 023 DYNAMICS OF CSF AND SAGITTAL SINUS PRESSURES PULSE WAVEFORM Marek Czosnyka1, Zofia Czosnyka1, Joseph Donnelly1, Nicholas Higgins, Angelos Kolias, Alasdair Parker, Matthew Garnett, John Pickard

1Academic Neurosurgery, Cambridge Biomedical Campus, United Kingdom 2Department of Radiology, Addenbrooke’s Hospital, Cambridge United Kingdom 3Department of Paediatric Neurology, Addenbrooke’s Hospital, Cambridge, United Kingdom

16:05 – 16:15 ABSTRACT NUMBER: 024 CLINICAL EXPERIENCE WITH TELEMETRIC INTRACRANIAL PRESSURE MONITORING IN PATIENTS WITH IDIOPATHIC INTRACRANIAL HYPERTENSION Alexander Lilja, Marianne Juhler Clinic of Neurosurgery, University Hospital of Copenhagen Rigshospitalet, Copenhagen, Denmark

34 16:15 – 16:25 ABSTRACT NUMBER: 025 ENDOVASCULAR TREATMENT CONSIDERATIONS IN IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) DUE TO IMPAIRED CEREBRAL VENOUS SINUS OUTFLOW Arun Chandran, Mani Puthuran, Hans Nahser, Catherine Harris The Walton Centre of Neurology and Neurosurgery, Liverpool, United Kingdom

16:25 – 16:35 ABSTRACT NUMBER: 026 THE NATURAL HISTORY OF SURGICALLY MANAGED IDIOPATHIC INTRACRANIAL HYPERTENSION IN ADULTS: A SINGLE CENTRE EXPERIENCE Samir Matloob, Ahmed Toma, Simon Thompson, Patricia Haylock-Vize, Amna Farrukh

Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom

SUPPLEMENTARY TESTING IN HYDROCEPHALUS Chairs: Laurence Watkins Masakazu Miyajima 16:35 – 17:00 CSF Biomarkers to Predict outcome in Post-haemorrhagic hydrocephalus James P. McAllister (USA)

17:00 – 17:10 ABSTRACT NUMBER: 027 ENDOGENOUS CSF PEPTIDES AND PROTEINS IN INPH; MULTIPLEXED QUANTITATIVE PROTEOMICS AND PEPTIDOMICS. Anna Jeppsson1, Mikko Hölttä2, Johan Gobom2, Henrik Zetterberg2, Kaj Blennow2, Carsten Wikkelsö1 1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy, University of Gothenburg, Sweden

17:10 – 17:20 ABSTRACT NUMBER: 028 CSF BIOMARKERS IN THE EVALUATION OF IDIOPATHIC INTRACRANIAL HYPERTENSION. Tetsuro Ishihara, Wataru Narita, Toru Baba, Osamu Iizuka, Yoshiyuki Nishio, Minoru Matsuda, Etsuro Mori

Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

17:20 – 17:30 ABSTRACT NUMBER: 029 ASSOCIATION OF LIPOCALIN-TYPE PROSTAGLANDIN D SYNTHASE WITH DISPROPORTIONATELY ENLARGED SUBARACHNOID-SPACE IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Namiko Nishida1, Nanae Nagata2, Hiroki Toda1, Naoto Jingami3, Kengo Uemura3, Akihiko Ozaki4, Mitsuhito Mase5, Yoshihiro Urade2 1Tazuke Kofukai Kitano Hospital, Osaka, Japan 2International Institute for Integrative Sleep Medicine, Tsukuba, Japan 3Kyoto University Graduate School of Medicine,Kyoto, Japan 4Saiseikai Nakatsu Hospital, Osaka, Japan 5Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan

35 17:30 – 17:40 ABSTRACT NUMBER: 030 DANDY’S FORGOTTEN PHENOLSULPHONEPHTHALEIN TEST AND MARMAROU’S INFUSION TEST: BIOPHYSICAL AND HYDRODYNAMIC SIDES OF THE SAME COIN? David Solomon, Ari Blitz, Daniele Rigamonti Johns Hopkins University, Baltimore, USA

17:40 – 17:50 ABSTRACT NUMBER: 031 CORRELATION OF ICP MONITORING TO CLINICAL HISTORY IN PATIENTS WITH HIGH OR LOW INTRACRANIAL PRESSURE SYMPTOMS, RELATED TO CSF CIRCULATION. Patricia Haylock-Vize, Simon Thompson, Chris Kellett, Ahmed Toma, Akbar Khan National Hospital for Neurology and Neurosurgery, Queen’s Square, United Kingdom

17:50 – 18:00 ABSTRACT NUMBER: 032 CEREBROSPINAL FLUID BIOMARKERS FOR LONG-TERM TREATMENT OUTCOMES PROGNOSIS IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Madoka Nakajima, Masakazu Miyajima, Ikuko Ogino, Chihiro Akiba, Hajime Arai Tokyo, Japan

Sunday 7th September

PEDIATRIC HYDROCEPHALUS I Chairs: Guirish Solanki Mark Luciano 08:00 – 08:30 The BASICS Trial Conor Mallucci (UK) 08:30 – 09:30 System changes to reduce shunt infection

Jay Riva-Cambrin (USA)

09:00 – 09:10 ABSTRACT NUMBER: 033 TELEMETRIC ICP MONITORING: INITIAL OBSERVATIONS OF CLINICAL AND COST IMPLICATIONS James Barber Royal Manchester Children’s Hospital, Manchester, United Kingdom

09:10 – 09:20 ABSTRACT NUMBER: 034 VENTRICULOPERITONEAL SHUNT COMPLICATIONS RELATED TO THE SURGICAL TREATMENT OF SPINAL SCOLIOSIS Hisashi Hatano1, Noriaki Kawakami2, Taichi Tsuji2, Tetsuya Ohara2, Yoshitaka Suzuki2, Ayato Nohara2, Toshiki Saito2 1Department of Neurosurgery, Japanese Red Cross Nagoya Daiichi Hospital, Nagoya, Japan 2Department of Orthopedics, Meijo Hospital, Nagoya, Japan

36 09:20 – 09:30 ABSTRACT NUMBER: 035 INFANT POST-HAEMORRHAGIC HYDROCEPHALUS (PHH) IN THE UK: IS IT TIME FOR A RANDOMISED CONTROLLED TRIAL? Bassel Zebian1, Wisam Al-Faiadh2, Florence Hoggs2, Vita Stagno1, Conor Mallucci1, Benedetta Pettorini1, Chris Chandler2, Sanj Bassi2 1Alder Hey Children’s NHS Foundation Trust, Liverpool, United Kingdom 2King’s College London School of Medicine, London, United Kingdom

09:30 – 09:40 ABSTRACT NUMBER: 036 UNRECOGNIZED HYDROCEPHALUS AS A RISK FACTOR FOR CSF LEAK AND WOUND BREAKDOWN FOLLOWING IMPLANTATION OF INTRATHECAL BACLOFEN PUMP Brian W Hanak, Luke Tomycz, Robert Oxford, Erin Hooper, Samuel Browd

University of Washington, Seattle, WA, USA

9.40- 10.00 BREAK & POSTER VIEWING

NEURORADIOLOGY II Chairs: Vartan Kurtcuoglu Marcus Bradley 10:00 – 10:30 MR Elastography in the evaluation of Hydrocephalus Ingolf Sack (Germany)

10:30 – 10:40 ABSTRACT NUMBER: 037 WATER TURNOVER IN BRAIN PARENCHYMA AND VENTRICLES ESTIMATED BY DYNAMIC PET USING H215O Mitsuhito Mase1, Emi Hayashi2, Kiminori Aoyama1, Hiroshi Yamada,1 Akihiko Lida2, Toshiaki Miyati3, Etsuro Mori4, Kazuo Yamada1 1Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan 2Department of Radiology, Nagoya City Rehabilitation Center, Nagoya, Japan 3Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 4Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University School of Medicine, Sendai, Japan

10:40 – 10:50 ABSTRACT NUMBER: 038 THREE-DIMENSIONAL VISUALIZATION OF VIRCHOW–ROBIN SPACES WITH 3-T MAGNETIC RESONANCE IMAGING Masatune Ishikawa, Shigeki Yamada Otowa Hospital, Kyoto, Japan

10:50 – 11:00 ABSTRACT NUMBER: 039 STOMA CLOSURE AFTER PRIMARY ETV FOR OBSTRUCTIVE HYDROCEPHALUS Eric Sankey1, Ignacio Jusue-Torres1, Jamie Hoffberger1, Ari Blitz2, Daniele Rigamon1

1Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA 2Division of Neuroradiology, The Russell H. Morgan Department of Radiology and Radiologic Science, The Johns Hopkins Hospital, Baltimore, USA

37 11:00 – 11:10 ABSTRACT NUMBER: 040 FINITE ELEMENT ANALYSIS ON PERIVENTRICULAR LUCENCY IN HYDROCEPHALUS: EXTRAVASATION OR TRANSEPENDYMAL CSF ABSORPTION?

Hakseung Kim1, Eun-Jin Jeong1, Dae-Hyeon Park1, Byung C Yoon2, Kiwon Kim3, Marek Czosnyka4, Dong-Joo Kim5 1Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea. 2Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, 3Department of Rehabilitation medicine, Seoul National University children’s Hospital, College of Medicine, Seoul, South Korea.USA 4Department of Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom. 5Korea University, Seoul, South Korea

11:10 – 11:20 ABSTRACT NUMBER: 041 CSF OSCILLATIONS INTEREST IN HYDROCEPHALUS PATIENTS Cyrille Capel1, Marc Baroncini2, Jérome Hodel3, Anthony Fichten1, Xavier Leclercq3, Olivier Balédent4 1Neurosurgery, Amiens, France 2Neurosurgery, Lille, France 3Radiology, Lille, France 4Image Processing Department, Amiens, France

11:20 – 11:30 ABSTRACT NUMBER: 042 THE RELATIONSHIP BETWEEN CSF OSCILLATIONS, CEREBRAL VASCULAR PULSATIONS AND BRAIN MORPHOLOGY Bader Chaarani1, Jadwiga Zmudka1,2, Roger Bouzerar1, Olivier Balédent1 1University Hospital of Amiens, France 2University of Picardy, Amiens, France

11:30 – 11:40 ABSTRACT NUMBER: 043 SHUNT SERIES, ARE THEY ESSENTIAL? Wai Cheong Soon, Ibrahim Djoukhadar, Jamie Clarke, Osamu Iizuka, Jeremy Macmullen-Price Imperial College NHS Trust, London, United Kingdom

11:40 – 11:50 ABSTRACT NUMBER: 044 CONGENITAL CHRONIC COMMUNICATING HYDROCEPHALUS WITH WIDE FORAMEN OF MAGENDIE AND DILATION OF CISTERNA MAGNUM: CLINICAL FEATURES AND CONGENITAL ETIOLOGIES Hiroshi Kageyama1, Ikuko Ogino1, Ryoko Fukai2, Noriko Miyake2, Kenichi Nishiyama3, Naomichi Matsumoto2, Hajime Arai1, Masakazu Miyajima1 1Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan 2Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan 3Brain Research Institute, University of Niigata, Niigata, Japan

11.50- 12.05 SOCIETY NOTICES: John Pickard - An Appreciation 12.05- 12.20 In Memorium

12.20- 13.00 KEYNOTE GUEST LECTURE (Anthony Marmarou Memorial Lecture): Randomised trials in pediatric hydrocephalus: the past, the present and the future

38 13.00- 13.40 LUNCH & POSTER VIEWING

SHUNT DESIGN

Chairs: Sam Browd Marek Czosnyka

13:40 – 14:10 Shunt valve design: simplicity or complexity? James Drake (Canada)

14:10 – 14:20 ABSTRACT NUMBER: 045

LABORATORY TESTING OF MICRO-ROBOTIC SELF-CLEANING VENTRICULAR CATHETER

Marek Czosnyka1, Zofia Czosnyka1, Joseph Donnelly1, Simon Sharon2, Yossi Porat2, Moshe Shohan2, Harel Gadot2, Or Samooha2

2Cambridge Shunt Evaluation Lab, Neurosurgical Division, Cambridge University Hospital, United Kingdom 2Microbot Medical Ltd, Israel

14:20 – 14:30 ABSTRACT NUMBER: 046

PROPOSAL OF A NEW GRAPH FOR SHUNT PERFORMANCE

Angelo Maset1, Gustavo Botelho1, Lucas Meguins1, Rodrigo Pinhabel1, Bruna Mancini2, Jose Andrade2, Sergio Ramin1, Dionei Moraes1. 1FUNFARME Sao Jose do Rio Preto Brazil 2Ventura Biomedica Ltd

14:30 – 14:40 ABSTRACT NUMBER: 047

RESURRECTION OF THE PUMPING TEST FOR OBSTRUCTION ? – EVALUATION OF A NEW FLUSHING RESERVOIR FOR SHUNTING OF HYDROCEPHALUS

Christian Sprung1, Thoralf Knitter2, Hans-Joachim Crawack2

1Neurosurgical Clinic, Charité, Universitätsmedizin Berlin, Germany, 2Methke GmbH, Potsdam, Germany

14:40 – 14:50 ABSTRACT NUMBER: 048

SHUNTS FOR HYDROCEPHALUS : REVISITING SOTELO’S CONCEPT

Angelo Maset, Gustavo Botelho, Lucas Meguins, Rodrigo Pinhabel, Bruna Mancini, Jose Camilo, Sergio Ramin, Dionei Moraes

Funfarme, S J Rio Preto, Brazil

14:50 – 15:00 ABSTRACT NUMBER: 049

CONTROLLING ICP THROUGH AUTOMATED FEEDBACK CONTROL

Kalyan Raman

Northwestern University, Evanston, USA

39 15:00 – 15:10 ABSTRACT NUMBER: 050

IN VITRO CHARACTERIZATION OF SIX TYPES OF ANTI-SIPHONING DEVICES

Florian Freimann1, Takaoki Kimura2, Veit Rohde1, Ulrich-Wilhelm Thomale3 1Department of Neurosurgery, University Medicine Göttingen, Georg-August University, Göttingen, Germany 2Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan 3Division of Pediatric Neurosurgery, Charité – University Medicine Berlin, Germany

13.00- 13.40 BREAK & POSTER VIEWING

EXPERIMENTAL HYDROCEPHALUS Chairs: Marianne Juhler Pat McAllister 15:30 – 16:00 Glymphatics: A new Paradigm For CSF Circulation Rashid Deane (USA)

16:00 – 16:30 The role of Aquaporins in Brain water balance Marios Papadopulos (UK)

16:30 – 16:40 ABSTRACT NUMBER: 051 THE POSITION-DEPENDENT INTRAPERITONEAL PRESSURE IN A LARGE ANIMAL MODEL

Florian Freimann, Veit Rohde, Christian Sprung, Stefan Wolf

Department of Neurosurgery, University Medicine Göttingen, Georg-August University, Göttingen, Germany

16:40 – 16:50 ABSTRACT NUMBER: 052 CORRELATIONS BETWEEN NEUROLOGICAL DEFICITS AND THE SEVERITY OF VENTRICULOMEGALY IN EXPERIMENTAL INFANTILE HYDROCEPHALUS

James McAllister1, Michael Williams2, Amanda Braun2, Robyn Amos-Kroohs2, Diana Lindquist3, Francesco Mangano3, Charles Vorhees2, Weihong Yuan3

1Washington University School of Medicine, St. Louis, MO, USA 2Division of Neurology, Cincinnati Children’s Research Foundation, Cincinnati, OH, USA 3University of Cincinnati College of Medicine, Cincinnati, OH, USA

16:50 – 17:00 ABSTRACT NUMBER: 053 THE DISTRIBUTION KINETICS OF IRON TAGGED DEXTRAN IN HYDROCEPHALUS IS DIFFERENT FROM THAT IN NORMAL (UNAFFECTED) RATS

Mark Haacke1, Satish Krishnamurthy2, Jie Li2, Yimin Shen1 1Wayne State University, Detroit, USA 2Upstate Medical University, Syracuse, USA

17:00 – 17:10 ABSTRACT NUMBER: 054 NEW HYPOTHESIS OF MECHANISM FOR CSF PRODUCTION AT THE CHOROID PLEXUS

Yasuhiko Hayashi, Daisuke Kita, Yu Shimizu, Masahiro Oishi, Seiichi Munesue, Yasuhiko Yamamoto, Yutaka Hayashi

Department of Neurosurgery, Kanazawa University, Kanazawa, Japan

40 17:10 – 17:20 ABSTRACT NUMBER: 055

DOES PHYSIOLOGICAL INTRACRANIAL PRESSURE IN UPRIGHT POSITION HAVE POSITIVE OR NEGATIVE (SUBATMOSPHERIC) VALUE?

Marijan Klarica1, Milan Radoš1, Ivana Jurjevi1, Antonio Petoši1, Darko Oreškovi2

1University of Zagreb, School of Medicine, Department of Pharmacology and Croatian Institute for Brain Research, Zagreb, Croatia 2Ruer Boškovi Institute, Department of Molecular Biology, Zagreb, Croatia

17:20 – 17:30 ABSTRACT NUMBER: 0056 Cerebrospinal Fluid Movement Using Magnetic Resonance imaging with Time Spin Labeling inversion pulse method in Canine hydrocephalus

Chieko Ishikawa1, Masato Kitagawa1, Daisuke Ito1, H Yamada1, Aya Sakurai2, Saeri Matsumoto2, Shinya Yamada2 Nihon University College of Bio-resource Science, Kanagawa, Japan1 Toshiba Medical Systems, Tochigi, Japan2

17.30 - 17.45 PRESIDENTIAL ADDRESS

17.45 - 18.30 ISHCSF BUSINESS MEETING

Monday 8th September CSF DYNAMICS Chairs: Anders Eklund Carsten Wikkelso 08:00 – 08.30 Assessment of apparent arrested hydrocephalus: to shunt or not to shunt Martin Schuhmann (Germany)

08:30 – 08:40 ABSTRACT NUMBER: 057

PRESSURE FORCE ON THE LATERAL VENTRICLE IS USEFUL TO PREDICT SHUNT RESPONSE FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS. Hisayuki Murai, Masayoshi Kobayashi, Shigeki Nakano, Naokatsu Saeki Department of Neurosurgery, Chiba University Graduate School of Medicine, Chiba, Japan

08:40 – 08:50 ABSTRACT NUMBER: 058 REDUCING OR INCREASING ICP PULSATION: EFFECT ON PARENCHYMAL BLOOD FLOW PULSATION

Sara Qvarlander1, Mark Luciano1, Stephen Dombrowski1, Francis Loth2, Serge El-Khoury1, Jun Yang1

1Cleveland Clinic, Cleveland, USA 2University of Akron, Akron, USA

08:50 – 09:00 ABSTRACT NUMBER: 059

DIRECT EVIDENCE OF VASCULAR COMPRESSION AND CEREBRAL CIRCULATORY DISTURBANCE IN NPH PATIENTS

Tomohisa Omura, Yoshinaga Kajimoto, Hiroji Miyake, Toshihiko Kuroiwa

Department of Neurosurgery, Osaka Medical College, Osaka, Japan

41 09:00 – 09:10 ABSTRACT NUMBER: 060

AGREEMENT OF PRESSURE AND WAVE AMPLITUDE RETRIEVED FROM THE LUMBAR SUBARACHNOID SPACE AND FROM THE BRAIN PARENCHYMA

Emilio González-Martínez1, David Santamarta2

1University Hospital of Álava, Vitoria, Spain 2University Hospital of León, León, Spain

09:10 – 09:20 ABSTRACT NUMBER: 061

CSF DYNAMIC SLOW VASOGENIC WAVES ARE SUPPRESSED BY GENERAL ANAESTHESIA

Zofia Czosnyka, Marek Czosnyka, Joseph Donnelly, Piotr Smielewski, Matthew Garnett, John Pickard

Academic Neurosurgery, Cambridge Biomedical Campus, UK

09:20 – 09:30 ABSTRACT NUMBER: 062

AN HYDRAULIC MODEL OF INTRACRANIAL SYSTEM: ROLE OF THE BRIDGING VEINS IN THE AUTOREGULATORY MECHANISMS

Carmelo Anile1, Antonio Ficola2, Pietro Santini1, Marek Czosnyka3 1Institute of Neurosurgery, Catholic University, Rome, Italy 2Department of Engineering, University of Perugia, Perugia, Italy 3Department of Clinical Neurosciences, University of Cambridge, UK

09:30 – 09:40 ABSTRACT NUMBER: 063

DOES AQUEDUCTAL STENOSIS INFLUENCE INFUSION TEST IN NORMAL PRESSURE HYDROCEFAPHALUS?

Emilio González-Martínez1, David Santamarta2

1University Hospital of Álava, Vitoria, Spain 2University Hospital of León, León, Spain

09:40 – 09:50 ABSTRACT NUMBER: 064

UNDERSTANDING THE PHYSICS OF OVERDRAINAGE

Christoph Miethke

Christoph Miethke GmbH&Co.KG, Germany

9.50- 10.10 BREAK & POSTER VIEWING

CLINICAL TRIALS Chairs: Jay Riva-Cambrin

Jan Malm 10.10 -10.30 “Study of Idiopathic Normal-Pressure Hydrocephalus On Neurological Improvement - Efficacy and safety of lumboperitoneal shunt-(SINPHONI-2)”

Presenters: Hiroaki Kazui and Masakazu Miyajima

065: EFFECT OF LUMBOPERITONEAL SHUNT SURGERY FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A RANDOMIZED CONTROLLED TRIAL (SINPHONI-2)

42 Hiroaki Kazui1, Etsuro Mori2, Masatsune Ishikawa3, Masakazu Miyajima4 1Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan 2Tohoku University, Sendai, Japan 3Normal Pressure Hydrocephalus Center, Otowa Hospital, Kyoto, Japan 4Department of Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan

066: LONG-TERM OUTCOME OF PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) TREATED WITH LUMBOPERITONEAL SHUNT (LPS): A MULTICENTER PROSPECTIVE STUDY (SINPHONI-2)

Masakazu Miyajima4, Hiroaki Kazui1, Etsuro Mori2, Masatsune Ishikawa3 1Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan 2Tohoku University, Sendai, Japan 3Normal Pressure Hydrocephalus Center, Otowa Hospital, Kyoto, Japan 4Department of Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan

10.30 -10.50 “A double-blind randomized trial on the complication rate and clinical effect of different shunt valve settings in idiopathic normal pressure hydrocephalus”

Presenter: Dan Farahmand

067: A DOUBLE-BLIND RANDOMIZED TRIAL ON THE CLINICAL EFFECT OF DIFFERENT SHUNT VALVE SETTINGS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Dan Farahmand1, Terje Sæhle2, Per Kristian Eide2, Magnus Tisell1, Per Hellström1, Carsten Wikkelsö1 1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Neurosurgery, Oslo University Hospital, Oslo, Norway

068: A RANDOMIZED CONTROLLED DOUBLE-CENTRE TRIAL ON SHUNT COMPLICATIONS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS TREATED WITH GRADUALLY REDUCED OR “FIXED” PRESSURE VALVE SETTINGS

Dan Farahmand1, Terje Sæhle2, Per Kristian Eide2, Magnus Tisell1, Per Hellström1, Carsten Wikkelsö1 1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Neurosurgery, Oslo University Hospital, Oslo, Norway

PEDIATRIC HYDROCEPHALUS II

Chairs: Graham Fieggen Richard Edwards 10.50 – 11:15 Drug Treatment of Infantile Hydrocephalus Ann Logan & Hannah Botfield (UK)

11:15 – 11:45 Ethical considerations in the treatment of severe congenital hydrocephalus Dominic Wilkinson (UK)

11:45 – 11:55 ABSTRACT NUMBER: 069 MILESTONES OF PROGRESS AND SETBACKS IN THE TREATMENT OF HYDROCEPHALUS - A LEARNING CURVE OF 40 YEARS Christian Sprung Neurosurgical Clinic, Charité, Universitätsmedizin Berlin, Germany

11:55 – 12:05 ABSTRACT NUMBER: 070 FETAL VENTRICULOMEGALY: WHAT DOES IT MEAN? Patricia Barrio1, Bienvenido Puerto2, Javier Pérez1, David Santamarta1 1Department of Neurosurgery. University Hospital of León (Spain) 2Department of Maternal – Fetal Medicine. ICGON, Clínic Hospital. University of Barcelona, IDIBAPS Barcelona (Spain)

43 12:05 – 12:15 ABSTRACT NUMBER: 071 ONE YEAR FAILURE RATES FOR DE-NOVO VENTRICULO-PERITONEAL SHUNTS IN UNDER 3-MONTH-OLD CHILDREN Gulam Zilani, Anthony Amato-Watkins, Jozef Lang, Imran Bhatti, Paul Leach Department of Paediatric Neurosurgery, University Hospital of Wales, Cardiff, United Kingdom

12:15 – 12:25 ABSTRACT NUMBER: 072 THE EXPLORATION OF HOW AND WHY SHUNTS OBSTRUCT Pat McAllister1, Carolyn Harris1, Kelsie Pearson1, Kristen Trett1, Badri Roysam2, Samuel Browd1, Bill Shain1. 1Seattle Children’s Hospital, Seattle, WA, USA 2University of Houston, Houston, TX, USA

12:25 – 12:35 ABSTRACT NUMBER: 073 CSF DYNAMICS IN PEDIATRIC PATIENTS PRESENTING AN INTRACRANIAL CSF VOLUME INCREASE Florine Dallery, Cyrille Capel, Bader Chaarani, Roger Bouzerar, Catherine Gondry-Jouet, Olivier Balédent University Hospital, Amiens, France

12.35 -13.30 Sponsored Lunchtime Seminar: BBraun

NORMAL PRESSURE HYDROCEPHALUS Chairs: Etsuro Mori John Pickard 13:30 – 13:55 Programmable valve setting in Adult Hydrocephalus Carsten Wikkelso (Sweden)

13:55 – 14:05 ABSTRACT NUMBER: 074

IMPACT OF CEREBROSPINAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS ON THE AMYLOID CASCADE

Masao Moriya, Masakazu Miyajima, Madoka Nakajima, Ikuko Ogino, Hajime Arai. Department of Neurosurgery, Kasai Shoikai Hospital, Tokyo, Japan

14:05 – 14:15 ABSTRACT NUMBER: 075

CLINICAL OUTCOMES IN SHUNTING IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS WITH AND WITHOUT ALZHEIMER DISEASE NEUROPATHOLOGIC CHANGES

Daniele Rigamonti, Ignacio Jusue-Torres, Mira Patel, Sachin Batra, Kathryn Carson, Barbara Crain, Abhay Moghekar, Jamie Hoffberger

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

14:15 – 14:25 ABSTRACT NUMBER: 076

DEPRESSION IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Hanna Israelsson1, Anders Eklund2, Jan Malm3

1Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden, 2Department of Radiation Sciences, Umeå University, Umeå, Sweden 3Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden

44 14:25 – 14:35 ABSTRACT NUMBER: 077

QUALITY OF LIFE IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Hanna Israelsson1, Anders Eklund2, Jan Malm3

1Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden, 2Department of Radiation Sciences, Umeå University, Umeå, Sweden 3Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden

14:35 – 14:45 ABSTRACT NUMBER: 078

LP SHUNT FOR INPH PATIENTS: SURGICAL TECHNIQUE AND COMPLICATIONS.― RETROSPECTIVE REVIEW OF 243 CASES.

Naoyuki Samejima, Nobumasa Kuwana, Akira Watanabe, Yojiro Seki Department of Neurosurgery, Tokyo Kyosai Hospital, Tokyo, Japan

14:45 – 14:55 ABSTRACT NUMBER: 079

NORMAL PRESSURE HYDROCEPHALUS: PROGNOSTIC VALUE OF HEIGHT IN PATIENTS TREATED WITH AN IDENTICAL SHUNT SYSTEM

Jesus Aguas1, Victor Rodrigo1, Francisco Estupiñan2, Pere Nogues3, Gloria Villalba1, Javier Villagrasa1, Luis Caral4

1S. Neurocirugía. Hospital Clínico Universitario, Zaragoza, Spain 2Instituto Aragonés de Ciencias de la Salud, Zaragoza, Spain 3Hospital Universitari Arnau de Vilanova, Lleida, Spain 4Hospital Clinic i Provincial, Barcelona, Spain

14:55 – 15:05 ABSTRACT NUMBER: 080

WEIGHT AND ABDOMINAL-PRESSURE INFLUENCED SHUNT TROUBLE (WAIST) IN SHUNTED NORMAL PRESSURE HYDROCEPHALIC PATIENTS: WHOLE PRESSURE ANALYSIS FOR OF SHUNT SYSTEM

Yoshinaga Kajimoto1, Tomohisa Oomura1, Hiroji Miyake2, Toshihiko Kuroiwa1

1Osaka Medical College, Takatsuki, Japan 2Nishinomiya Kyouritu hospital, Nishinomiya, Japan

15:05 – 15:10 ABSTRACT NUMBER: 081

HEALTH-RELATED QUALITY OF LIFE OF PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Antti Junkkari1, Harri Sintonen,2 Ossi Nerg1, Anne Koivisto1, Risto Roine3, Heimo Viinamäki4, Juha Jääskeläinen1, Ville Leinonen1

1Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 2Department of Public Health Science, University of Helsinki, Helsinki Finland 3Hospital District of Helsinki and Uusimaa, Uusimaa 4Department of Psychiatry, Institute of Clinical Medicine, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland

15:10 – 15:15 ABSTRACT NUMBER: 082

CLINICAL OUTCOMES AND COMPLICATIONS AFTER VENTRICULOATRIAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A LARGE MULTICENTER STUDY

Ignacio Jusue-Torres1, Mira Patel1, Jamie Hoffberger1, Juan Ramon-Cuellar2, Fernando Hakim1, Daniele Rigamonti1

1Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA 2Department of Neurosurgery. Santa Fe de Bogota Foundation. Bogota D.C., Colombia

45 15:15 – 15:20 ABSTRACT NUMBER: 083

FAMILIAL NORMAL PRESSURE HYDROCEPHALUS: A NOVEL SUBGROUP Takeo Kato1, Yoshimi Takahashi1, Shinji Ono2, Naoyuki Samejima3, Masakazu Miyajima4, Kazuya Aoki5, Shinya Yamada6, N Kuwana1, H Arai1.

1Department of Neurology, Hematology, Metabolism, Endocrinology and Diabetology, Yamagata University Faculty of Medicine, Yamagata, Japan 2Department of Psychiatry, Nagasaki University Graduate School of Medicine, Nagasaki, Japan 3Department of Neurosurgery, Tokyo Kyosai Hospital, Tokyo, Japan 4Department of Neurosurgery, Juntendo University, Tokyo, Japan 5Department of Neurosurgery, Hokushin-Kai Megumino Hospital, Hokkaido, Japan 6Department of Neurosurgery, Toshiba Rinkan Hospital, Kanagawa, Japan

15:20 – 15:25 ABSTRACT NUMBER: 084

CLINICAL OUTCOMES AND COMPLICATIONS AFTER VENTRICULOATRIAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Mira Patel, Ignacio Jusue-Torres, Jamie Hoffberger, Daniele Rigamonti Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

15:25 – 15:30 ABSTRACT NUMBER: 085

THE LAUNCESTON IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS PREVALENCE STUDY: A TREATABLE DEMENTIA, MISSED DIAGNOSIS

George Razay1, Melissa Razay1, Iain Robertson2

1Launceston General Hospital, Launceston, Australia 2School of Human Life Sciences, University of Tasmania, Launceston

15:30 – 15:35 ABSTRACT NUMBER: 086

BASIC CONCEPT AND USEFULNESS OF INITIAL VALVE PRESSURE SETTING QUICK REFERENCE TABLE BY WEIGHT AND HEIGHT

Yoshinaga Kajimoto1, Tomohisa Oomura1, Hiroji Miyake2, Toshihiko Kuroiwa1

1Osaka Medical College, Takatsuki, Japan 2Nishinomiya Kyouritu hospital, Nishinomiya, Japan

15:35 – 15:40 ABSTRACT NUMBER: 087

LONG TERM BENEFIT OF VP SHUNT INSERTION IN PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS

Flavia Somavilla, Ahmed Toma, Amna Farrukh, Samir Matloob, Patricia Haylock – Vize, Mustafa Anjari, Simon Thompson, Laurence Watkins National Hospital for Neurology and Neurosurgery, Queen’s Square, United Kingdom

15:40 – 15:45 ABSTRACT NUMBER: 088

COMPUTERIZED NEUROPSYCHOLOGICAL TESTING IN iNPH BEFORE AND AFTER SHUNT SURGERY

Anders Behrens1, Anders Eklund2, Eva Elgh1 Jan Malm1

1Department of Clinical Neuroscience, Umeå, Sweden 2Department of Radiation Sciences, Umeå, Sweden

46 15.45 - 16.05 BREAK & POSTER VIEWING

ADULT HYDROCEPHALUS Chairs: Masatsune Ishikawa Mark Hamilton 16:05 – 16:30 Mapping cerebrospinal fluid movement using magnetic resonance spin labelling in complex hydrocephalus Shinya Yamada (Japan)

16:30 – 16:40 ABSTRACT NUMBER: 089

HYDROCEPHALUS IN ADULTS WITH COMMUNITY ACQUIRED BACTERIAL MENINGITIS

Ivan Pelegrin1, Roger Bayston2, Javier Ariza1, Pedre Viladrich1, Carmen Cabellos1

1Infectious Diseases Department. IDIBELL-Hospital Universitari Bellvitge, Barcelona, Spain. 2School of Medicine, University of Nottingham, United Kingdom

16:40 – 16:50 ABSTRACT NUMBER: 090

AN UNDERECOGNIZED CAUSE OF HYDROCEPHALUS: ADULT CHOROID PLEXUS HYPERPLASIA. CASE SERIES Daniele Rigamonti, Jacob Cox, Ignacio Jusue-Torres, Shiv Gaglani, Michael Haynes, Ari Blitz

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

16:50 – 17:00 ABSTRACT NUMBER: 091 YOUNG AULT IDIOPATHIC AQUEDUCT STENOSIS SPECTRUM; FOCUSING ON MEDICAL HISTORY AND CHRONOLOGICAL RADIOLOGICAL IMAGES

Daisuke Kita, Yasuhiko Hayashi, Issei Fukui, Yutaka Hayashi, Masaaki Hashimoto

Department of Neurosurgery, Kanazawa University Hospital, Kanazawa, Japan

17:00 – 17:10 ABSTRACT NUMBER: 092

NEGATIVE PRESSURE HYDROCEPHALUS: POSSIBLE AETIOLOGY, CSF HYDRODYNAMICS AND PRINCIPLES OF SUCCESSFUL TREATMENT

Asim Mujic, Benjamin Hunn, Asad Sheikh, Andrew Hunn, Albert Erasmus, Jens Peters-Willke, Arvind Dubey

Royal Hobart Hospital, Hobart, Australia

17:10 – 17:20 ABSTRACT NUMBER: 093

MANAGEMENT OF PERSISTENT ORTHOSTATIC HEADACHE: THE ROLE OF INTRACRANIAL PRESSURE MONITORING, INFUSION STUDIES AND IMAGING

Mustafa Anjari, Ahmed Toma, Simon Thompson, Samir Matloob, Amna Farrukhm, Patricia Haylock-Vize, Flavia Somavilla, Laurence Watkins

National Hospital for Neurology and Neurosurgery, Queens Square, London, United Kingdom

47 Abstracts

NEURORADIOLOGY I

O-001: NARROWING OF HIGH CONVEXITY/MIDLINE SUBARACHNOID SPACES PREDICTS THE EFFECTIVENESS OF CEREBROSPINAL FLUID SHUNTING IN PATIENTS WITH NORMAL-PRESSURE HYDROCEPHALUS

Tetsuro Ishihara, Wataru Narita, Toru Baba, Osamu Iizuka, Yoshiyuki Nishio, Minoru Matsuda, Etsuro Mori

Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

Background: Different neuroimaging features have been suggested as predictors of the response to cerebrospinal fluid (CSF) shunting in patients with idiopathic normal-pressure hydrocephalus (iNPH). This study aimed to evaluate the usefulness of various neuroimaging biomarkers, including high-convexity/midline tightness, as prognostic tools for the selection of candidates with iNPH who are eligible for CSF shunting.

Methods: This study included 42 patients diagnosed with probable iNPH on the basis of the Japanese Guidelines for Management of Idiopathic Normal Pressure Hydrocephalus, second Edition, who underwent CSF shunt surgery between January 2006 and April 2013. Preoperative brain magnetic resonance imaging or computed tomography scans were evaluated for Evans index, sylvian fissure dilatation, high convexity subarachnoid spaces and the callosal angle. The outcomes of surgery were assessed using the iNPH grading scale (iNPHGS) before and 12 months after surgery. Postoperative improvement was defined as an increase of ≥1 point(s) in the iNPHGS total score. Results: Totally, 71% patients exhibited an improvement in the total iNPHGS score at 1 year after shunt surgery, and the improvement was significantly greater in patients with narrowing of high convexity/midline subarachnoid spaces than in those without narrowing. Sylvian fissure dilatation, the callosal angle and Evans index did not correlate with long-term clinical outcomes.

Conclusions: Narrowing of high convexity/midline subarachnoid spaces after CSF shunt surgery predicts a good outcome in patients with iNPH.

NEURORADIOLOGY I

O-002: A COMPARISON OF THE DISPROPORTIONATELY ENLARGED SUBARACHNOID SPACE (DESH) PATTERN TO THE AQUEDUCTAL CSF STROKE VOLUME IN PATIENTS WITH CLINICAL NPH

William Bradley, Abdulrahman Almutairi

University of California, San Diego, San Diego, USA

Abstract:

Background: We have used the finding of hyperdynamic CSF flow through the aqueduct to predict whether NPH patients will respond to shunting or not for over 30 years. For the past 23 years we have measured the Aqueductal CSF Stroke Volume (ACSV) using phase contrast MRI. An elevated ACSV correlates with ventricular enlargement and lack of atrophy and has a very high positive predictive value for response to shunting in appropriately symptomatic patients.

Methods: The DESH pattern was described 4 years ago and consists of an Evans index > 0.3 and qualitatively enlarged Sylvian cisterns and a tight superior convexity subarachnoid space. We acquired coronal images along with the ACSV in 31 patients with suspected NPH. They all had a positive tap test and ACSVs ranging from 75-255 uL (normal: 40 uL).

Results: Rather than do a qualitative assessment of DESH, we drew a line connecting the gyri over the superior convexities. CSF superior to the line was considered “convexity volume” and CSF inferior was considered “sulcal volume”. Amira 5.5 software was used to manually segment the CSF in these two spaces as well as the volume of CSF in the Sylvian cisterns and lateral ventricles. Two slabs of CSF were evaluated: that in the 5mm midcoronal slice and that in the volume spanned by the Sylvian cisterns from front to back.

Conclusions: While there was excellent correlation between lateral ventricular volume and ACSV (p = .018), there was no correlation between the Sylvian/high convexity volume ratio and the ACSV (p=.72 for the full Sylvian volume and p=.579 for the midcoronal slice). While this lack of correlation may be due to different head shapes in our population vs the Japanese population, caution should be exercised when using this sign to predict shunt-responsiveness for NPH.

48 NEURORADIOLOGY I

O-003: RELATIONSHIP BETWEEN TEMPORAL CHANGES OF THE REGIONAL APPARENT DIFFUSION COEFFICIENT AND THE INTRACRANIAL COMPLIANCE IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Mitsuhito Mase1, Toshiaki Miyati2, Tomoshi Osawa1, Hiroshi Yamada1, Naoki Ohno2, Hirohito Kan3, Harumasa Kasai3, Kazuo Yamada1

1Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan 2Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 3Department of Radiology, Nagoya City University Hospital, Nagoya, Japan

Background: We have reported that patients with idiopathic normal pressure hydrocephalus (iNPH) had significantly larger ADC (temporal changes of apparent diffusion coefficient) of cerebral white matter, however, the mechanism of causing the larger ADC has not been known. In this study, we discuss the mechanism from the point of view of intracranial compliance.

Methods: (1) On a 1.5-T MRI, ECG-triggered single-shot diffusion echo planar imaging was used to obtain ADC images.ADC image was calculated from maximum minus minimum ADC value of all cardiac phase images (20 phases) on a pixel-by- pixel basis. ADC values in the white matter were obtained iNPH (n=14), atrophic ventricular dilatation (VD group; n=9), and healthy volunteers (control group; n=8).

(2) Net blood flow (bilateral internal carotid and vertebral arteries and jugular veins) and cerebrospinal fluid (CSF) flow in subarachnoid space at the C2 level of cervical vertebrae were measured using phase-contrast cine MRI, and CSF pressure gradient (PG) and intracranial volume changes (ICVC) during a cardiac cycle were calculated.

Results: ADC of the frontal white matter in the iNPH group was significantly higher than in the control and VD groups, which significantly decreased after a tap test and shunt surgery with improvement of symptoms. The compliance index (CI=ICVC/ PG) in the iNPH group was significantly lower than in the control and VD groups. CI values of iNPH patients after the tap test were larger than those before. The shape of time-ADC curve was very similar to the time-ICVC curve.

Conclusions: Both ADC and CI are affected in iNPH, which are normalized after a tap test or shunt surgery with clinical improvements. Tighter condition (less pressure compensation, low compliance) in iNPH could bring large ADC changes (larger water fluctuation). This energy change of water molecules in white matter might be one of causes of clinical symptoms.

NEURORADIOLOGY I

O-004: CEREBRAL PERFUSION MEASURED WITH PCASL BEFORE AND REPEATEDLY AFTER CSF REMOVAL IN iNPH PATIENTS

Johan Virhammar1, Katarina Laurell2, André Ahlgren,3 Kristina Cesarini1, Elna-Marie Larsson4

1Department of Neuroscience, Neurology, Uppsala University, Sweden 2Department of Pharmacology and Clinical Neuroscience, Neurology, Östersund, Umeå University, Sweden 3Department of Medical Radiation Physics, Lund University, Sweden 4Department of Radiology, Uppsala University, Sweden

Background: Pseudo-continuous arterial spin labeling (pCASL) is a perfusion MRI method that can provide absolute quantification of cerebral blood flow (CBF) without contrast agent injection. The aim was to study changes in CBF and their relationship with clinical improvement during the first 24 h after CSF removal in patients with iNPH. A secondary aim was to measure the repeatability of pCASL in patients with iNPH.

Methods: Pseudo-continuous arterial spin labeling (pCASL) measurements were performed in 20 patients with iNPH. Five pCASL scans were performed. Two scans were performed before removal of 40 mL CSF, and the others at 30 min, 4 h, and 24 h after the CSF TT. Thirteen different regions of interest (ROIs) were manually drawn on coregistered MR images. Gait analysis was performed in connection with the pCASL investigations.

Results: In patients with increased CBF in lateral and frontal white matter after the CSF TT, gait function improved more than it did in patients with decreased CBF in these regions. However, in the whole sample, there was no significant increase in CBF after CSF removal compared with baseline investigations. The repeatability of CBF measurements at baseline was high, with intraclass correlation coefficients (ICC) of 0.60–0.90 for different ROIs, but the median regional variability was in the range of 5–17%.

Conclusions: Our results indicate that CBF in white matter close to the lateral ventricles plays a role in the reversibility of symptoms after CSF removal in patients with iNPH.

49 NEURORADIOLOGY I

O-005: DEVELOPMENT OF AUTOMATED SEGMENTATION OF X-RAY COMPUTED TOMOGRAPHY (CT) FOR THE DIAGNOSIS OF SHUNT-RESPONSIVE IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (iNPH)

Robin Holmes1, Will Singleton2, Alex Mortimer3, Claire Doddy4, Richard Edwards2

1Medical Physics, University Hospitals Bristol NHS Foundation Trust, Bristol, United Kingdom 2Department of Neurosurgery, North Bristol NHS Trust, Bristol, United Kingdom 3Department of Neuroradiology, North Bristol NHS Trust, United Kingdom 4Medical Physics, North Bristol NHS Trust, Bristol, United Kingdom

Background: Recent studies have suggested that analysis of ventricular shape and size, in particular disproportionately enlarged subarachnoid-space hydrocephalus (DESH), may be useful to predict shunt-responsiveness in patients with a syndrome consistent with a diagnosis of iNPH.. In our institution CT scans are routinely used in the initial assessment of patients with suspected iNPH rather than MRI. Consequently, in order to analyze patient images, software developed for MRI tissue segmentation in relatively normal brain has had to be modified for the lower contrast in CT and the distorted ventricles in iNPH.

Methods: Retrospective analysis of pre-operative CT scans of patients who have undergone shunt surgery for iNPH. X-ray CT scans with 0.5 x 0.5 x 3mm voxel size were segmented using Statistical Parametric Mapping version 8 initially using CSF priors derived from MRI. The CSF maps from the ~40% of successful segmentations were used to create a new prior map; this procedure was repeated until ~95% of CT scans were successfully processed. The findings were correlated with prospective clinical analysis of shunt response defined as an improvement in MMSE of 2 points or more +/- a 20% improvement in Raftopolous gait analysis.

Results: 85 preoperative CT scans have been analysed. This preliminary analysis revealed significant differences in CSF density between shunt responders and non-responders (P<0.001 at the voxel level uncorrected for multiple comparisons). Further analysis is required to improve segmentation and to identify further correlations with clinical findings.

Conclusions: Further work is required to analyse all available patient scans using all available outcome measures. However, CSF has been successfully segmented from patient scans and differences between groups have been depicted. A recent publication indicates that grey matter (GM) can be segmented from CT scans using modern software – the combination of CSF and GM segmentation with multivariate classifiers shows promise.

NEURORADIOLOGY I

O-006: AMYLOID DEPOSITS AND RESPONSE TO SHUNT SURGERY IN IDIOPATHIC NORMAL-PRESSURE HYDROCEPHALUS

Manabu Tashiro1, Nobuyuki Okamura1, Katsutoshi Furukawa,2 Hiroyuki Arai3, Ren Iwata3, Etsuro Mori4, Kazuhiko Yanai5

1Division of Cyclotron Nuclear Medicine, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan 2Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan 3Department of Geriatrics and Gerontology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan 4Division of Radiopharmaceutical Chemistry, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan 5Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

Background: 18.5 to 67.6% of idiopathic normal-pressure hydrocephalus (iNPH) patients reportedly had Alzheimer pathology including senile plaques in the studies using frontal lobe cortical biopsy during shunt surgery or intracranial pressure monitoring. In cases of diagnosing iNPH, comorbidity of or differential diagnosis from Alzheimer’s disease (AD) are somteimes problems. Objectives: We aimed to evaluate amyloid deposition in the brain of iNPH patients before shunt surgery, and to investigate association between amyloid burden in the brain and clinical improvement following shunt surgery.

Methods: Amyloid imaging was performed in iNPH, AD, and healthy control subjects using positron emission tomography (PET) and a radiolabeled pharmaceutical compound, 11C-BF227. Using cerebellar hemispheres as reference regions, the standard uptake value ratio (SUVR) of the neocortex was estimated, which was regarded as an index of amyloid deposits. In iNPH subjects, clinical symptoms were assessed before and 3 months after shunt surgery.

Results: In 5 out of 10 iNPH subjects, neocortical SUVRs were as high as those of AD subjects, while those of the latter 5 iNPH subjects were as low as those of healthy control subjects. Significant correlation between the neocortical SUVRs and cognitive improvements after shunt suregery were observed in iNPH. The less amyloid deposits were estimated in PET imaging, the more cognitive improvement was observed after shunt surgery.

Conclusions: There are amyloid-positive and amyloid-negative iNPH patients. 11C-BF227-PET may be useful for predicting the cognitive improvement after shunt surgery.

50 NEUROENDOSCOPY

O-007: PRIMARY VS. SECONDARY ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) FOR OBSTRUCTIVE HYDROCEPHALUS

Ignacio Jusue-Torres, Eric Sankey, Jamie Robison, Jan Wemmer, Rory Goodwin, Jamie Hoffberger, Ari Blitz, Daniele Rigamonti

John Hopkins Hospital, Baltimore, MA, USA

Background: CISS MRI aids in both pre- and postoperative evaluation of CSF flow patterns and postoperative ventriculostomy patency. Here, we compare the clinical and radiological outcomes between primary (non­previously shunted) and secondary ETV (previously shunted) in patients with obstructive hydrocephalus followed with CISS MRI.

Methods: We retrospectively reviewed the clinical and radiographic data of 151 consecutive patients, treated between 2007 and 2013, with ETV for hydrocephalus. Twelve patients with communicating hydrocephalus were excluded. Of the 139 patients with obstructive hydrocephalus, ETV was primary in 84 (60%) patients and secondary in 55 (40%). Median follow-up duration was 14 (329)­ months. Median age was 50 (3762)­ years at treatment. Clinical outcome was reported as a percentage of improvement/worsening of the presenting symptoms. ETV patency was assessed by CISS MRI.

Results: At last followup­ (LFU), 89 (64%) patients improved, 32 (23%) were unchanged, 8 (6%) worsened, and 10 (7%) had no clinical data available. No statistically significant differences in clinical (p>0.05) or radiological outcomes (p>0.05) were observed between primary and secondary ETV. However, compared to primary ETV, secondary ETV had significantly higher rates of recurrence (p=0.001) and revision (p=0.001). Patients with secondary ETV were significantly younger (p=0.01). Primary ETV showed significant associations between better clinical outcomes and younger age (rho=­0.86, 95%CI (­1.37­ ­0.34) p=0.002), faster Timed Up and Go (TUG) (rho=1.96,­ 95%CI (3.60­ ­ ­0.32) p=0.03) and higher Tinetti score (rho=2.64 95%CI (0.99­4.29) p=0.004). Likewise, patients with primary ETV, who showed better radiological outcomes, were younger (p=0.000003). Secondary ETV had a hazards ratio (HR) for recurrence of 2.06 95%CI (1.123.82)­ p=0.02 and a HR for surgical revision of 2.007 95%CI (1.0673.774)­ p=0.03.

Conclusions: Our study suggests that better clinical and radiological outcomes in patients with obstructive hydrocephalus, who undergo ETV as first treatment, are associated with younger age and/or better TUG and Tinetti scores.

NEUROENDOSCOPY

O-008: INTRACRANIAL NEUROENDOSCOPIC EXPERIENCE AND COMPLICATION RATES IN 273 ADULT AND PEDIATRIC PATIENTS: A POPULATION-BASED STUDY WITH LONG-TERM FOLLOW-UP

Mark Hamilton, Roberto Diaz, Walter Hader, Fady Girgis

University of Calgary, Calgary, Alberta, Canada

Background: Neuroendoscopy is often thought of as a pediatric hydrocephalus procedure. We examine and contrast the role of intracranial neuroendoscopy in both a pediatric and adult population with minimum 5-year post-procedure followup.

Methods: A retrospective review was conducted for patients in the two hospitals that manage neurosurgical care for Southern Alberta undergoing neuroendoscopic surgery between 1994 and 2008. The pediatric group was defined as age ≤ 17 and the adult group as age ≥ 18 years.

Results: 273 patients were identified who underwent a total of 330 procedures with a mean post procedure followup of 12.9 years. There were 161 adult and 112 pediatric patients. The most common procedure was endoscopic third ventriculostomy (ETV) accounting for 55% of procedures, followed by cyst fenestration (16%), colloid cyst removal (10%), tumor biopsy (8%), and septostomy (5%). One postoperative death occurred in an adult patient. ETV success one-year post procedure was 81% with only 3 late-term failures. Postoperative infection was the most common serious complication (2 pediatric/4 adult), followed by permanent neurologic deficit (1 pediatric/3 adult), permanent endocrine dysfunction (3 pediatric), and subdural hematoma (2 pediatric). Although adult and pediatric patients had similar major complication rates (4.2% vs. 5.7%, p = 0.712), there was a significant trend toward lower complication rates as patient age increased (R2 = 0.32, p = 0.021).

Conclusion: Neuroendoscopy overall has a similar role in both the pediatric and adult patient neurosurgical populations with a higher percentage of pediatric patients undergoing cyst fenestration, while a higher percentage of adults underwent ETV, colloid cyst removal, and tumor biopsy. ETV success was 81% at one year and late ETV failures are uncommon. The most common complication associated with neuroendoscopy was infection, and complication rates significantly trended downwards with increasing patient age. Neuroendoscopy should be considered as a potential therapeutic modality in the management of appropriate adult patients.

51 NEUROENDOSCOPY

O-009: PAEDIATRIC ENDOSCOPIC THIRD VENTRICULOSTOMY - LONG TERM FOLLOW UP

Matthew Stovell1, Michael Jenkinson2, Bassel Zebian1, Benedetta Pettorini1, Conor Mallucci1

1Alder Hey, Liverpool, United Kingdom 2Walton Centre, Liverpool, United Kingdom

Background: Endoscopic third ventriculostomy (ETV) is an effective treatment for obstructive hydrocephalus that avoids the risk of foreign body infection associated with ventriculo-peritoneal (VP) shunts. The reported short term failure rate of an ETV will depend very much on the indications used, but is generally thought to be lower in the long term compared to VP shunts. There are few studies with very long term follow up of ETV for paediatric hydrocephalus however.

Methods: 113 children (neonates – 16 years old) had primary or secondary ETV for different causes of hydrocephalus between April 1998 and June 2006. Patient medical records and our electronic operation database were reviewed for evidence of further surgery (repeat ETV or VP shunt insertion). These were checked at the paediatric and adult neurosurgical hospital for those patients who had their care transferred to adult services.

Results: Median follow up was thirteen and a half years (range 8 – 16 years). Fifty two patients (46%) required further ETV or VP shunt insertion for ETV failure overall. Twenty five patients (22%) required a second procedure within one month, seventeen patients (15%) between one month and one year, seven patients (6.2%) between one year and five years and three patients (2.7%) between five and eight years.

Conclusion: In our series, ETV has an initial early failure rate for the treatment of paediatric hydrocephalus as is reported elsewhere dependent very much on age and aetiology. Once stabilised and effective, ETV seems to be durable but NOT guaranteed and there is some late drop off with some failures occurring many years later. Successful ETV thus cannot be guaranteed for life and some form of follow up is recommended long term into adulthood.

NEUROENDOSCOPY

O-010: ENDOSCOPIC THIRD VENTRICULOSTOMY ON TREATMENT OF SHUNT-INDUCED SLIT VENTRICLE SYNDROME Guo-Qiang Chen, Qing Xiao, Jia-ping Zheng

Aviation General Hospital of China Medical University, Beijing, China

Background: To investigate the treatment effectiveness of endoscopic third ventriculostomy on treatment of shunt-induced slit ventricle syndrome.

Methods: Clinical data of 18 cases of shunt-induced slit ventricle syndrome from June, 2005 to July,2013 was analyzed retrospectively. Male 11 cases, female 7 cases, aged from 12 to 48 years old with mean of 22.4-year-old. The interval to shunt operation is 1 to 12 years with mean of 4 years. Intermittent headache, nausea, vomiting and drowsiness were the presenting symptoms which lasting 1 week to 10 years. All the cases had neuroimaging proof of ever slit ventricle. 10 cases with dilated ventricle on admission while 8 cases present with slit ventricle. Direct endoscopic third ventriculostomy was performed to those cases with dilated ventricle, shunt deligation to dilate the ventricle and followed by endoscopic procedure to those cases with slit ventricle.

Results: Among 18 cases, ventricle catheter was encapsulated by choroid plexus or ingressed into brain parenchyma in 13 cases, shunt was endoscopic dislodged successfully in 12 cases while un-dislodged due to tight encapsulation in 6 cases. The improvement of clinical symptoms presented in 16 cases after endoscopic third ventriculostomy, shunt open to the other 2 cases with no symptomatic relief. Unconsciousness presented in 1 case 12 hours after shunt deligation and recovered after endoscopic procedure. Postoperative infection cured by second endoscopic procedure to dislodge the residual ventricle catheterer present in 1 case.

Conclusion: Endoscopic procedure is an alternative for treatment of shunt-induced slit ventricle syndrome.

52 NEUROENDOSCOPY

O-011: IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) OUTCOMES AFTER PRIMARY ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV)

Ignacio Jusue-Torres, Eric Sankey, Ari Blitz, Jamie Hoffberger, Daniele Rigamonti

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

Background: The efficacy of ETV for iNPH remains controversial. Here, we evaluate if patients with iNPH showed clinical improvement after primary ETV.

Methods: We performed a retrospective cohort study of 8 consecutive patients with iNPH, who underwent ETV between 2009 and 2011. One patient was excluded due to previous shunt placement. Seven patients, aged 73 (70-79) years at treatment with a median Evan’s ratio of 0.36 (0.34-0.39), received ETV as their initial surgery. Median follow-up was 39.1 (33.6-43.8) months. Post-ETV aqueductal and cisternal flow was confirmed via MRI. Post-ETV Timed Up and Go (TUG) and Tinetti scores were compared to pre- and post-LP values. A second LP was performed if ETV failed to sustain the observed improvement after initial LP, despite stoma patency. After ETV failure, patients who demonstrated improvement after LP were considered for shunting. Quantitative data are expressed in medians and interquartile ranges.

Results: Compared to Pre-LP TUG and Tinetti values of 15.6 (13.0-20.8) seconds and 22.0 (20.8-23.3), post-LP scores significantly improved to 10.5 (9.8-11.8, p=0.0472) seconds and 25.5 (25.0-26.0, p=0.0029), respectively. ETV failed to sustain this improvement, with insignificant differences between pre-LP and post-ETV TUG and Tinetti scores of 15.0 (11.0- 17.5, p=0.6085) seconds and 21.0 (18.0-22.5, p=0.8972), respectively. All patients showed symptomatic ETV failure and were subsequently shunted after displaying improvement from pre-LP values following a second-LP, with a TUG of 12.5 (11.0-12.9, p=0.09761) seconds and Tinetti of 24.5 (24.0-25.8, p=0.0492). Improvement from pre-LP assessment was maintained with post-shunt TUG and Tinetti scores of 13.0 (10.7-16.3, p=0.2496) seconds and 25.0 (21.0-25.0, p=0.1734), and last follow-up (LFU) totals of 11.9 (10.4-16.0, p=0.1520) seconds and 23.0 (21.3-23.8, p=0.3821), respectively.

Conclusions: Despite stoma patency, ETV failed to sustain clinical improvement after LP in patients with iNPH. Our data suggests that shunt placement remains the preferred treatment for this patient population

YOUNG INVESTIGATORS AWARD

O-012: RELATIONSHIP BETWEEN FLEXION OF THE NECK AND CHANGES IN INTRACRANIAL PRESSURE Sarah Skovlunde Hornshøj, Morten Andresen, Alexander Lilja, Dorthe Christoffersen, Marianne Juhler

Neurokirurgisk klinik, NK 2092, Rigshospitalet, Copenhagen, Denmark

Background: Intracranial pressure (ICP) monitoring at our department includes a standardized postural change examination to evaluate its effects on ICP. During these procedures we observed that neck flexion caused an increase in ICP in one patient. To clarify if the observation was a random occurrence or if it could be reproduced, we added neck flexion and extension to the standard examination. We report the consecutive preliminary results of these measurements.

Methods: All patients undergoing invasive ICP monitoring at our department were included prospectively. The postural change examination consists of eight standard postures including both horizontal and vertical positions. In this abstract we focus specifically on the effect of neck flexion on ICP with the patient sitting upright with a straight back, and 1) straight neck and 2) maximal neck flexion. Each posture was maintained for ten minutes. We recorded ICP and demographic data.

Results: 19 patients completed the standardized measurements, (13 female). Flexion of the neck caused an increase in ICP in all patients. The median ICP with 1) a straight neck was –5 mmHg (range –28 to 2 mmHg) while the median ICP with 2) neck flexion was 5,6 mmHg (range –18 to 12,6 mmHg). The median increase in ICP when flexing the neck was 8,5 mmHg (range 3,8 to 13,0 mmHg). The increase in ICP when flexing the neck was highly significant (p < 0,001).

Conclusion: The results indicate that the position of the neck has a more important influence on ICP than previously presumed. We speculate that the increase in ICP is a result of either compression of the jugular veins or the vertebral canal.

53 YOUNG INVESTIGATORS AWARD

O-013: THE DISEASE STATE INDEX IN PREDICTION OF SHUNT SURGERY OUTCOME IN IDIOPATHIC NORMAL-PRESSURE HYDROCEPHALUS

Antti Luikku, Anette Hall, Maria Kojoukhova, Jussi Mattila, Jyrki Lötjönen, Juha Jääskeläinen, Ville Leinonen

Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland

Background: Disease State Index (DSI) and Disease State Fingerprint (DSF) represent a novel clinical decision making tool which collates data information from different sources, to help the clinician in the diagnosis and follow-up of dementia diseases. It has previously been demonstrated to be useful in differentiating Alzheimer’s disease, frontotemporal dementia and mild cognitive impairment. In this study we use the Disease State Index method to predict shunt surgery response for patients with idiopathic normal-pressure hydrocephalus (iNPH) and evaluate its use in treatment prediction.

Methods: A total of 552 patients (230 patients with response to shunt, 54 patients without shunt response and 268 without shunt) from the Kuopio NPH registry were analyzed with the DSI. Analysis included data from patients’ neuropsychological tests, age, clinical symptoms, comorbidities, medications, frontal cortical biopsy, CT/MRI imaging (disproportion, temporomesial atrophy, superior medial spaces) and intracranial pressure.

Results: The DSI was applied for comparisons at the group level. Our analysis showed that patients with response to shunt could be differentiated with moderate accuracy from patients without shunt (AUC 0.75). Accuracy was lower when differentiating patients without response from those without shunt (AUC 0.65) and lowest when comparing patients without response to those with response (AUC 0.61). Additionally, we demonstrated use of DSF by comparing one patient with shunt response to those without shunt and without response.

Conclusions: DSI and DSF were found to be useful when analyzing incomplete patient data, regardless of only moderate differentiation between study groups. CT/MRI data proved to be the best measurement when comparing patients with shunt response to those without response, while as symptoms were the best differentiating patients without shunt and with response. The fact that extensive patient data-set accomplished only with moderate accuracy between shunted groups highlights the need of new predictors for determining patients’ response to shunt surgery.

YOUNG INVESTIGATORS AWARD/ADULT HYDROCEPHALUS

O-014: INTRACRANIAL PRESSURE IN HYDROCEPHALUS: IMPACT OF SHUNT ADJUSTMENTS AND BODY POSITIONS Dan Farahmand1, Sara Qvarlander2, Jan Malm3, Carsten Wikkelsö1, Anders Eklund2, Magnus Tisell1

1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Radiation Sciences, Umeå University, Sweden 3Department of Clinical Neuroscience, Umeå University, Sweden

Background: The association between intracranial pressure (ICP) and different shunt valve opening pressures in relation to body positions is fundamental for understanding the physiological function of the shunt. Objective: To analyse the ICP and ICP wave amplitude (AMP) at different shunt settings and body positions in hydrocephalus patients.

Methods: In this prospective study 15 patients with communicating hydrocephalus were implanted with a ligated adjustable ventriculoperitoneal shunt. They also received a portable intra-parenchymatous ICP-monitoring device. Postoperative ICP and AMP were recorded with the patients in three different body positions (supine, sitting and walking) and with the shunt ligated and open at high, medium and low valve settings. In each patient 12 ten minute segments were coded, blinded and analysed for mean ICP and mean AMP using an automated computer algorithm.

Results: Mean ICP and mean AMP were lower at all three valve settings compared to the ligated shunt state (p<0.001). Overall, when compared to the supine position, mean ICP was 11.5±1.1 (mean±SD) mmHg lower when sitting and 10.5±1.1 mmHg lower when walking (p<0.001). Mean ICP was overall 1.1 mmHg higher (p=0.042) when walking compared to sitting. The maximal adjustability difference (highest vs lowest valve setting) was 4.4 mmHg.

Conclusions: Changing from a supine to an upright position reduced ICP while AMP only increased at trend level. Lowering of the shunt valve opening pressure decreased ICP and AMP but the difference in mean ICP in vivo between the highest and lowest opening pressures was less than half that previously observed in vitro.

54 YOUNG INVESTIGATORS AWARD

O-015: EVANS INDEX AND SYMPTOMS OF NORMAL PRESSURE HYDROCEPHALUS - AN EPIDEMIOLOGICAL INVESTIGATION

Daniel Jaraj1, Katrin Rabie1, Tom Marlow1, Christer Jensen2, Ingmar Skoog1, Carsten Wikkelsø1

1Institute of neuroscience and phyisiology, Gothenburg University, Gothenburg, Sweden 2Institute of clinical sciences, Gothenburg university, Gothenburg, Sweden

Background: Evans Index (EI), defined as the largest width of the frontal horns divided by the inner diameter of the skull, is commonly used to assess ventricular enlargement in patients with NPH. A value higher than 0.3 is considered pathological and is included in the iNPH guidelines. However, few epidemiological studies have been made on elderly persons and EI. The aim of this study was to examine the frequency of ventricular enlargement defined as EI>0.3 in a large representative sample of elderly persons. We also aimed to correlate EI with symptoms of NPH.

Methods: Study design, cross-sectional, population-based. 1236 men and women aged 70 years and older were included. All persons were systematically selected from the general population and had previously undergone neuropsychiatric examinations, including CT of the brain. We assessed CT images and measured EI. Cognitive impairment was defined as MMSE<25, gait disturbance was assessed based on physical examination and self-report. Urinary incontinence was assessed based on self-report.

Results: In persons aged 70 to 92 years, EI ranged from 0.11 to 0.46. The frequency of EI>0.3 was 20.6 %. Men had higher values than women (0.29 vs 0.27), p<0.001. Mean values of EI were also higher in older age groups, i.e. those aged 80+ compared to those who were 70-79 years (0.29 vs 0.27), p<0.001. Adjusting for age and gender, persons with EI>0.3 had higher risks cognitive impairment OR 3.4 (95%CI 2.3-5.1), gait disturbance, OR 3.1 (95%CI 2.1-4.4) and urinary incontinence, OR 4.2 (95%CI 2.8-6.3).

Discussion: Data from our preliminary results show that ventricular enlargement, defined as EI>0.3, is common among elderly persons in the general population. We found significant correlations between high values of EI and symptoms of NPH.

YOUNG INVESTIGATORS AWARD SESSION

O-016: FEASIBILITY OF RADIOLOGICAL MARKERS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Maria Kojoukhova1, Anna Sutela2, Anne M Koivisto3, Jaana Rummukainen 4, Anne Remes5, Ritva Vanninen2, Juha E Jääskeläinen1, Ville Leinonen1, Irina Alafuzoff6, Hilkka Soininen3

1Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 2Department of Radiology, Kuopio University Hospital, Kuopio, Finland 3Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 4Department of Pathology, Kuopio University Hospital, Kuopio, Finland 5Neurology of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 6Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland and Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University and Department of Pathology and Cytology, Uppsala University Hospital. Kuopio, Finland

Background: Despite previous research, it is still unclear, which are the most valuable radiological markers in the diagnostics of idiopathic normal pressure hydrocephalus (INPH). This study was performed to examine usefulness of previously reported radiological markers in the diagnostics and prediction shunt response of INPH.

Methods: In this study we used NPH-registry of Kuopio University Hospital from 1991 until 2010. CT or MRI (n=125) was available of altogether 396 patients who were classified as non-NPH (n=183) and possible INPH (n=213) based on the results of 24 h intraventricular pressure measurement. In total 224 patients underwent a shunt surgery and 187 of them improved after the surgery. Size of four cerebrospinal fluid (CSF) compartments (lateral ventricles, sylvian and suprasylvian subarachnoid (SA) spaces, basal cisterns) were visually assessed. Disproportionally enlarged SA spaces, flow void, white matter changes and focally dilated sulcae (FDS) were evaluated. Also, computational markers ((Evan’s index (EI), modified cella media index (mCMI) and callosal angle (n=60)) were assessed.

Results: Patients with strong volumetric disproportion between suprasylvian and sylvian SA spaces had considerably more likely INPH than those without disproportion in logistic regression model (OR 6.6, CI95%: 3.6-12.0, P<0.0001). Also, mild disproportion was associated with INPH diagnosis (OR 2.5, CI95%: 1.4-4.5, P=0.001). CSF size of sylvian and suprasylvian SA spaces, basal cisterns and FDS were individually associated with INPH diagnosis in separate cross-tabs (P=0.005), but only disproportion was significantly associated with the diagnosis in combined binary logistic model. Interestingly, EI was lower among non-NPH than INPH patients (0.40 vs. 0.38, P=0.01). Visual assessment of ventricle size, flow void, white matter changes, mCMI or callosal angle were not associated with INPH diagnosis. Radiological markers assessed before the surgery were not associated with shunt response.

Conclusion: Visually evaluated SA-disproportion was the most useful marker in the diagnostics of INPH.

55 YOUNG INVESTIGATORS AWARD

O-017: REFINING NON-INVASIVE TECHNIQUES TO MEASURE INTRACRANIAL PRESSURE: COMPARING EVOKED AND SPONTANEOUS TYMPANIC MEMBRANE DISPLACEMENTS

Laurie Finch, Anthony Birch, Robert Marchbanks, Diederik Bulters

University of Southampton, Southampton, United Kingdom

Background: The cochlear aqueduct is a channel through which intracranial pressure (ICP) equalises with inner-ear (or perilymphatic) fluid pressure (PLP. Tympanic membrane displacement measurements (TMDs) can be used to gauge PLP non- invasively and thereby indirectly measure ICP. There are two types of TMD. Evoked TMDs are reflex responses to auditory stimuli. Spontaneous TMD describes pulsatile tympanic membrane (TM) movements expressed as TMD-pulse amplitudes (TMD-PAs). We investigated whether both TMD types respond in a similar way to a change in ICP and thus via a common mechanism.

Methods: ICP was manipulated in 20 healthy adults using a postural change from sitting (lower ICP) to supine (higher ICP). Evoked and spontaneous measurements were taken in each posture.

Results: The TM can displace inward (negative TMD) or outward (positive TMD). Evoked TMDs became more inward on lying supine (median change= -169.6nl, p=0.0002, 95.9%CI -226.8nl to -59.2nl). This supports previous studies and can be explained by the established stapes-footplate mechanism; rises in mean ICP alter the resting position of the stapes footplate in the oval window such that reflex movements of the stapes become more inward. Spontaneous TMDs became more outward on lying supine (median change=148.6nl, p=0.003, 95.9%CI 70.6nl to 328.3nl). Furthermore, there was no evidence of a correlation between the change in evoked TMD and the change in spontaneous TMD between postures (r= -0.38, p=0.10, 95%CI -0.75 to 0.21).

Conclusions: In a cohort with presumed normal intracranial compliance, evoked and spontaneous TMDs respond independently to changing ICP. Spontaneous TMD is therefore not influenced by the resting position of the stapes footplate in these healthy subjects. The spontaneous TMD waveform is likely to have intracranial and extracranial components. The degree to which intracranial factors dominate is unclear; however trends in the polarity of TMD-PA values are difficult to explain by extracranial vascular factors alone.

YOUNG INVESTIGATORS AWARD

O-018: NATURAL COURSE OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Kerstin Andrén, Per Hellström, Carsten Wikkelsö, Magnus Tisell

Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden

Background: The natural course of idiopathic normal pressure hydrocephalus (iNPH) has not been thoroughly studied. The consequences of postponing shunt treatment are largely unknown. We aimed to describe the effects of waiting for more than six months before surgery, and to compare the outcome to that seen in patients who waited for less than three months.

Methods: Thirty-three patients (iNPHDelayed) underwent an initial investigation (Pre-op 1), followed by re-examination, just prior to surgery, after waiting for at least 6 months (Pre-op 2). Outcome was evaluated after three months of treatment. Sixty-nine patients who were surgically treated within three months after Pre-op 1 and who were also evaluated after three months of treatment constituted a comparison group (iNPHEarly). Evaluations were done with the iNPH scale and the modified Rankin Scale (mRS). INPHDelayed patients were prospectively studied, whereas the comparison group iNPHEarly was defined and analysed retrospectively.

Results: iNPH delayed patients deteriorated significantly during their wait for surgery, with progression of symptom severity ranging from +7 to – 47 on the iNPH scale, and from 0 to +3 on the mRS (both p<.001). The magnitude of change after surgery was similar in the two groups, but since the symptoms of iNPHDelayed patients had worsened while waiting their final outcome was significantly poorer.

Conclusions: The natural course of iNPH is symptom progression over time, with worsening in gait, balance and cognitive symptoms. This deterioration is only partially reversible by shunt surgery. To maximize the benefits of shunt treatment, surgery should be performed soon after diagnosis.

56 YOUNG INVESTIGATORS AWARD

O-019: IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS AND VASCULAR RISK FACTORS - A POPULATION-BASED STUDY

Simon Agerskov, Daniel Jaraj, Katrin Rabiei, Thomas Marlow, Christer Jensen, Ingmar Skoog, Carsten Wikkelsø

Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden

Introduction: The exact pathophysiology and risk factors for idiopathic normal pressure hydrocephalus (iNPH) are poorly understood. Previous studies have found associations between iNPH and vascular risk factors, particularly hypertension. However, most of these were made on small samples using selected groups of cases and controls. The aim of this study was therefore, to perform a population-based study on a representative sample in order to examine the associations between iNPH and several possible vascular risk factors.

Methods: The study population was from the western region of Sweden and consisted of a representative cohort of 1236 men and women aged 70 years or more. All probands had previously undergone neuro-psychiatric examinations between 1986 and 2000, including CT of the brain. We used data from radiological and clinical examinations to identify probands with probable iNPH (n=26), as well as those with radiological signs of iNPH (n=55). Data on risk factors and comorbidities were obtained from interviews and from the Swedish hospital discharge register. Five controls were randomly selected per case, matched for age, gender and exam year. The following variables were assessed: hypertension, diabetes, stroke, history of atherosclerotic- and heart disease, smoking, obesity, alcoholism and depression.

Results: The frequency of hypertension was significantly higher in probands with clinical iNPH than in controls (42.9% vs 21.2%, OR 2,790 (95%CI 1,057-7,364), p=0,033) Similarly, the frequency of hypertension was significantly higher in probands with radiological iNPH compared to controls (45,5% vs 26,9%, OR 2,266 (95% CI 1,172-4,379), p=0,013). Also, the frequency of diabetes was higher in probands with iNPH but the differences were not significant (p=0.091).

Conclusion: This is, to our knowledge, the first population-based study on the risk factors for iNPH. Our preliminary results suggest that vascular risk factors might be involved in the pathogenesis of iNPH.

YOUNG INVESTIGATORS AWARD

O-020: 2.4% OF MOUSE GENE KNOCKOUTS SHOW ENLARGED BRAIN VENTRICLES: A RESOURCE TO IDENTIFY GENES RELATED TO INFANTILE CONGENITAL HYDROCEPHALUS

Helen Whitley1, Anna Mikhaleva2, Amélie Baud3, Valerie E. Vancollie4, Andrew Edwards1, Meghna Kannan5, Christel Wagner5, Anaïs Duret5, Isabel Herr2, Jeanne Estabel3, Christopher J. Lelliott3, Jacqueline K. White3, David J. Adams3, David A. Keays6, Jonathan Flint1, Yann Hérault5, Alexandre Reymond6, Binnaz Yalcin5

1Welcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford, United Kingdom 2Center for Integrative Genomics, University of Lausanne, Switzerland 3EMBL-European Bioinformatics Institute, Hinxton, Cambridge, United Kingdom 4Welcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom 5Institute of Genetics and Molecular and Cellular Biology, Illkirch, France 6Research Institute of Molecular Pathology, 1030 Vienna, Austria

Background: Congenital hydrocephalus is a complex condition caused by obstruction of the cerebrospinal fluid flow that leads to enlargement of the ventricles. Although it is one of the most frequent congenital malformations of the central nervous system, very little is known about the genetic basis of the condition. It is assumed that genetic lesions account for the majority of the cases of infantile congenital hydrocephalus with unknown aetiology. Only few genes are known to date including L1CAM, AP1S2, MPDZ, and CCDC88C, which play a role in the pathogenesis of human hydrocephalus.

Methods: To identify genes causing hydrocephalus and other brain malformations, we are collaborating with the Sanger Mouse Genetics Project (MGP), allied to the International Mouse Phenotyping Consortium (IMPC), to systematically study ventricle size of the MGP/IMPC knockout mouse strains. To do this, we use six quantifiable measurements of lateral, third and fourth ventricles amongst 72 other brain measurements, relating them to normal values for the wild type strain.

Results: So far, we have assessed 545 mouse gene knockouts. Preliminary data yielded success with the identification of 13 genes causing mild to severe enlargement of the ventricles, including genes involved in cilium function (Cep41), axonogenesis (Slitrk4) or signal transduction (Arl4d). In two cases, this was also correlated to a neurological or behavioral phenotype in the mouse.

Conclusions: Our study is the widest quantitative screen of brain ventricle size using knockout mice from the MGP/IMPC. We can detect significant enlargement of ventricle size in about 2.4% of mouse gene knockouts. Our resource offers a complementary approach to the identification of genes related to infantile congenital hydrocephalus in human cohorts.

57 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE

O-021: EFFECT OF INTRACRANIAL HYPERTENSION ON COGNITION: IMPLICATIONS FOR SPACE TRAVEL Abhay Moghekar, Daniele Rigamonti, David Solomon

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

Background: Intracranial hypertension causes headaches and visual symptoms but its effect on cognition has not been well characterized and its correlation to duration of symptoms, degree of intracranial hypertension, concurrent medication use, has not been studied.

Methods: Patients who presented to the CSF Disorders Clinic from July 2009 to June 2013 with a new diagnosis of pseudotumor cerebri underwent a detailed neuropsychological battery. Clinical information was obtained simultaneously regarding lumbar punctures, medications and visual function. The raw scores were converted to age, sex and education appropriate “z” scores for analysis.

Results: There were 30 patients with IIH, all female, with a mean age of 32.3 years with a mean of 14 yrs of education. On cognitive assessment they performed within 1.5 SD of the mean in general cognitive ability, attention, verbal memory, visuospatial construction, category and semantic fluency but performed less than 1.5 SD in confrontational naming and executive tasks. These observations were independent of the degree of intracranial hypertension as measured by opening pressure, use of medications, severity of visual impairment as measured by visual acuity and color vision and duration of symptoms.

Conclusions: We present the largest cohort of IIH patients who have undergone detailed cognitive assessments. Unlike previous reports we found that executive function is affected to a greater degree than all the other domains, independent of multiple confounders. The effect of intracranial hypertension on cognition needs to be considered in long duration space travel as intact executive function is likely more important than all mental faculties.

IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

O-022: THE OPTIC NERVE COMPARTMENT SYNDROME. DOES IT EXPLAIN PAPILLEDEMA IN ASTRONAUTS?

Esriel Killer1, Neil Miller2, Luca Remonda1

1Kantonsspital Aarau Switzerland 2Wilmer Institute, Johns Hopkins, Baltimore USA

Background: Cerebrospinal fluid (CSF) has been thought to be consistent in both pressure and content throughout all CSF spaces. This concept has been challenged by findings in patients with unilateral or highly asymmetrical papilledema as well as patients with persistent papilledema despite normalized intracranial pressure (ICP). For this condition, the term optic nerve compartment syndrome (ONCS) was coined. Optic disc swelling in astronauts after space travel may be another example of a optic nerve compartment syndrome.

Methods: Contrast-loaded computed tomographic (CT) cisternography was used to compare the CSF dynamics between the intracranial CSF spaces and the subarachnoid space (SAS) surrounding the optic nerves (ONs) in patients with papilledema. The concentration of contrast-loaded CSF (CLCSF) was compared between the intracranial SAS (basal cistern) and the SAS of the ONs.

Results: Contrast-loaded cisternography demonstrated a progressively reduced influx of CLCSF from the intracranial CSF spaces into the SAS surrounding the ONs. The lowest concentration of CLCSF was found in the region of the ON immediately behind the globe, a region that was distended by CT scanning in all patients to a variable degree compared with normal subjects

Conclusions: The progressive decrease in the concentration of CLCSF from the optic canal towards the retrobulbar portion of the ON just posterior to the globe suggests that the structure of the trabeculae and septae and the menigothelial cells that cover these structures as well as the pia and the arachnoid layer in the SAS may play an important role in the development of the ONCS.

58 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

O-023: DYNAMICS OF CSF AND SAGITTAL SINUS PRESSURES PULSE WAVEFORM Marek Czosnyka1, Zofia Czosnyka1, Joseph Donnelly1, Nicholas Higgins, Angelos Kolias, Alasdair Parker, Matthew Garnett, John Pickard

1Academic Neurosurgery, Cambridge Biomedical Campus, United Kingdom 2Department of Radiology, Addenbrooke’s Hospital, Cambridge United Kingdom 3Department of Paediatric Neurology, Addenbrooke’s Hospital, Cambridge, United Kingdom

Background: Little is known about relationship between the waveforms of CSF and sagittal sinus pressures. Clinically this area of research has been restricted to Idiopathic Intracranial Hypertension (IIH) as this syndrome has been described to present with collapsible walls of cranial dural sinuses.

Methods: We studied mixed group of adults (N=11; ten with clinical and radiographic features of IIH and one moderate TBI with a fixed narrowing of the transverse sinus and post-traumatic headaches), and two children diagnosed with IIH. In all adults we measured simultaneous lumbar CSF pressure (CSFp) and sagittal sinus pressure (SSp) during a constant rate lumbar infusion study. In children we measured only CSFp during infusion test.

Results: In adults with IIH, CSFp and SSp were strongly correlated (R=0.95) both at baseline and during elevation of both pressures by lumbar infusion. In adults IIH cases, a rise or decrease (drainage) in CSFp was followed by similar reaction of SSp, but in the mild TBI patient, such a coupling was not observed. Pulse amplitude of SSp was lower than of CSFp (p<0.001), with diastolic pressure of SSp matching diastole of CSFp. In adults IIH patients, increases in pulse amplitudes of SSp and CSFp during the lumbar infusion were strongly associated (R=0.92), but again, this was not observed in the TBI patient. In the two children, very high CSFp (>40 mm Hg) were noted at a baseline, and changes in pulse amplitude of CSFp at this stage were inversely proportional to changes in mean CSFp (RAP index was negative). This inverse proportionality was reversed during lowering of CSFp by CSF drainage (RAP became positive)

Conclusion: Pulse amplitude of CSFp and SSp are strongly associated with each other in IIH but not in TBI. Critical CSFp in IIH in children can be clearly observed with analysis of CSFp amplitude/mean pressure relationship.

IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

O-024: CLINICAL EXPERIENCE WITH TELEMETRIC INTRACRANIAL PRESSURE MONITORING IN PATIENTS WITH IDIOPATHIC INTRACRANIAL HYPERTENSION

Alexander Lilja, Marianne Juhler

Clinic of Neurosurgery, University Hospital of Copenhagen Rigshospitalet, Copenhagen, Denmark

Background: Management of idiopathic intracranial hypertension (IIH) often relies on assessment of visual function or ophthalmoscopic findings. These measures may be inaccurate or difficult to assess in cases with advanced disease. Measurements of lumbar or intracranial pressure (ICP) are increasingly used, but require repeated invasive procedures. Telemetric ICP monitoring allows continuous measurements in the patient’s everyday life and the possibility to perform additional measurements without the procedure related risks of repeated transducer insertions.

Methods: We identified all patients with IIH in our clinic with an implanted Raumedic telemetric ICP probe (NEUROVENT-P-tel) between September 2011 and June 2014. For each patient we identified the number of ICP recording sessions (in relation to symptoms of increased ICP) and their result. The clinical consequence of ICP monitoring was classified in 3 entities: 1) no action, 2) change in drug dose or programmable valve setting, and 3) surgical shunt revision. Surgical complications as well as reason for explantation (if performed) were also noted.

Results: We included 9 patients in the evaluation (6 female and 3 male), which had implanted a total of 11 telemetric probes. Indication for implantation was to guide medical treatment and to avoid unnecessary invasive procedures in difficult cases. Median age was 33 years and median duration of disease was 2 years before implantation. All patients except one were previously treated with acetazolamide and 3 had a ventriculo-peritoneal shunt implanted. Median implantation period of the telemetric probe was 452 [68-867] days and median duration from implantation to last recording session was 267 [27- 529] days. No surgical complications occurred during the implantation procedures. One patient had 3 implantations, since the first implantation was complicated by a wound infection and the second probe malfunctioned after 5 months. A total of 41 recording sessions were performed in the 9 patients. Among these sessions, 14 led to a change in drug dose or programmable valve setting, 16 warranted surgical shunt revision and 11 sessions required no direct action. In many cases it was possible to directly verify the effect of an intervention on the mean ICP or the prevalence of pathological waveforms in subsequent monitoring sessions.

Conclusion: Telemetric ICP monitoring is useful in patients with IIH, who would otherwise require repeated invasive pressure monitoring to document treatment effect. It seems to be a feasible method to guide adjustment of programmable valve settings and dosing of medication. It is also valuable in identification of shunt dysfunction in difficult cases, where chronic headache is often present.

59 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

O-025: ENDOVASCULAR TREATMENT CONSIDERATIONS IN IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) DUE TO IMPAIRED CEREBRAL VENOUS SINUS OUTFLOW

Arun Chandran, Mani Puthuran, Hans Nahser, Catherine Harris

The Walton Centre of Neurology and Neurosurgery, Liverpool, United Kingdom

Background: Over recent years cerebral venous hypertension has been implicated in the pathophysiology of IIH. The final common pathway, that of venous outflow impairment, causing reduced CSF reabsorption is the favoured hypothesised mechanism. The aim of this study is to assess our experience of endovascular management strategies. The utility of both primary venous sinus angioplasty and stenting for refractory IIH have been examined. To our knowledge, clinical outcome from primary cerebral sinus venoplasty alone has not been described in the literature as a treatment option for IIH.

Methods: Twenty-two patients with refractory IIH had cerebral venous sinus manometry to assess for pressure gradient across the lateral sinus (March 2012 to April 2014). Primary venous angioplasty or secondary stenting was performed. Clinical outcomes were documented on cases with evidence of a positive pressure gradient.

Results: Twelve out of the 22 cases showed positive pressure gradients and had endovascular management with variable reduction of the pressure gradient. Nine (7 had only sinus venoplasty and 2 had sinus stenting) out of 12 showed clinical improvement or resolution of symptoms. Three patients were refractory to endovascular management and stabilised after ventriculo-peritoneal shunt.

Conclusion: The pathophysiology of IIH from venous hypertension secondary to venous outflow impairment is controversial. A selected group of patients with IIH and cerebral venous outflow impairment can benefit from endovascular treatment. In our experience more than 50% of patients showed clinical improvement on primary sinus venous angioplasty. This is a potential alternative to CSF diversion or perhaps more invasive primary stenting of the sinus.

IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

O-026: THE NATURAL HISTORY OF SURGICALLY MANAGED IDIOPATHIC INTRACRANIAL HYPERTENSION IN ADULTS: A SINGLE CENTRE EXPERIENCE

Samir Matloob, Ahmed Toma, Simon Thompson, Patricia Haylock-Vize, Amna Farrukh

Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, London, United Kingdom

Background: Idiopathic intracranial hypertension (IIH) is a rare condition that is often managed conservatively. In a sub-group of these patients surgical options are indicated. Such options include CSF diversion, optics nerve sheath fenestration and more recently, venous sinus stenting. There is little data on the outcomes of these patients when surgically managed. We describe our experience of surgically managed IIH and the outcomes of these patients. In particular the surgical revision rate and interventions required for resolution of symptoms.

Methods: A retrospective case series study of all patient files coded with benign intracranial hypertension, idiopathic intracranial hypertension or pseudotumour cerebri was undertaken. Files were searched with the date of diagnosis and the date these patients were referred for surgical intervention. The surgical interventions and complications were then documented and note was made of the number of inpatient admissions and days spent in hospital.

Results: From 2000-2013, 79 patients were identified as patients with IIH that had required surgical intervention with a mean follow up of 6.6 years (+/- 4.2 years). 52% required more than 1 surgical intervention. The average number of surgical interventions for the total population was 5.6 (+/- 5.5). For patients requiring further intervention, the average number of surgical interventions was 8.6 (+/-5.6). On average, total population spent 42 (+/- 53) inpatient days in neurosurgical beds, whilst those patients who required further intervention spent 63 (+/- 64) days on average in neurosurgical beds.

Conclusion: Based on our experience, patients that require surgical management of IIH frequently require further surgical interventions to control symptoms and manage complications of CSF diversion surgery. Those that require such further intervention on average will have 6 further operations and spend significantly longer in hospital. This sub-group of patients therefore requires specialist neurosurgical input for this long term and challenging pathological process.

60 SUPPLEMENTARY TESTING IN HYDROCEPHALUS

O-027: ENDOGENOUS CSF PEPTIDES AND PROTEINS IN INPH; MULTIPLEXED QUANTITATIVE PROTEOMICS AND PEPTIDOMICS.

Anna Jeppsson1, Mikko Hölttä2, Johan Gobom2, Henrik Zetterberg2, Kaj Blennow2, Carsten Wikkelsö1

1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden

2Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy, University of Gothenburg, Sweden

Background: Previous data has pointed towards a reduced periventricular metabolism in patients with idiopathic normal pressure hydrocephalus (iNPH) as evident by reduced APP and amyloid38, 40 and 42 protein levels in CSF. This study aimed at getting a broader profile of the endogenous CSF peptides and protein content in lumbar CSF in iNPH by using a novel method of multiplexed quantitative proteomics and peptidomics.

Methods: Twenty patients diagnosed with iNPH as defined by iNPH guidelines at the Hydrocephalus unit, Sahlgrenska University Hospital and 20 neurologically healthy elderly individuals (HI) were included.Lumbar CSF was collected from the HI and preoperatively from the patients; assessed clinically pre-operatively and 6 month after shunt operation. The CSF samples were analyzed using isobaric labeling based on the tandem mass tag approach (TMT 6-plex) combined with liquid chromatography-mass spectrometry (LC-MS) analysis. Briefly, the CSF samples were labeled with TMT 6-plex and the endogenous peptides were separated from the proteins using molecular weight cut off filters (30 kDa), where after the proteins were subjected to on-filter trypsinization. The endogenous and tryptic peptides were analyzed with LC-MS with which identification and quantification of the peptides were made.

Results: Data shows lower levels of a large number of endogenous CSF peptides and proteins in lumbar CSF of patients with iNPH patients in comparison with neurologically healthy controls, among others NPY peptides and proteins involved in glucose/carbohydrate metabolism

Conclusions: This unique data on endogenous CSF peptides and protein levels in CSF of patients with iNPH might provide a piece in understanding the CNS metabolism of patients with iNPH.

SUPPLEMENTARY TESTING IN HYDROCEPHALUS

O-028: CSF BIOMARKERS IN THE EVALUATION OF IDIOPATHIC INTRACRANIAL HYPERTENSION. Tetsuro Ishihara, Wataru Narita, Toru Baba, Osamu Iizuka, Yoshiyuki Nishio, Minoru Matsuda, Etsuro Mori

Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

Backgroud: The aetiology of idiopathic intracranial hypertension (IIH) is unknown and the search for biomarkers to better understand the condition and aid diagnosis is broad. CSF-Tau and beta amyloid (AB42) biomarkers are used in the diagnosis and assessment of neuronal degenerative conditions. For the first time, we compare these biomarker levels in the IIH patient group against established healthy reference ranges.

Methods: CSF was obtained in 17 patients with diagnosed idiopathic intracranial hypertension (IIH). The samples were analysed for CSF-Tau, AB42 and CSF-Tau/AB42 ratios and compared to established normal levels for age group.

Results: The mean age of this group was 36.3 years ranging from 20 to 57 years old. Patients were divided into the following age categories for CSF-Tau normal reference ranges. In total, 58.82% of IIH patients demonstrated raised biomarkers compared to their age group, with one patient falling outside of the established age reference ranges. There was no age correlate with AB42 or CSF-Tau/AB42 ratio levels.

Conclusion: In our group of IIH patients, we noted the CSF-Tau was consistently above the normal accepted limit for age. This suggests a new reference level is necessary for this patient population and leads us further on the path of understanding the underlying pathophysiology.

61 SUPPLEMENTARY TESTING IN HYDROCEPHALUS

O-029: ASSOCIATION OF LIPOCALIN-TYPE PROSTAGLANDIN D SYNTHASE WITH DISPROPORTIONATELY ENLARGED SUBARACHNOID-SPACE IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Namiko Nishida1, Nanae Nagata2, Hiroki Toda1, Naoto Jingami3, Kengo Uemura3, Akihiko Ozaki4, Mitsuhito Mase5, Yoshihiro Urade2

1Tazuke Kofukai Kitano Hospital, Osaka, Japan 2International Institute for Integrative Sleep Medicine, Tsukuba, Japan 3Kyoto University Graduate School of Medicine,Kyoto, Japan 4Saiseikai Nakatsu Hospital, Osaka, Japan 5Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan

Abstract:

Bckground: Lipocalin-type prostaglandin D synthase (L-PGDS) is a major cerebrospinal fluid (CSF) protein produced by arachnoid cells, and its concentration is reportedly decreased in idiopathic normal pressure hydrocephalus (iNPH). L-PGDS behaves as a chaperone to prevent the neurotoxic aggregation of amyloid beta (Aβ) implicated in Alzheimer’s disease, a major comorbidity of iNPH. The aim of this study was to clarify its relevance for a unique morphological entity of iNPH called disproportionately enlarged subarachnoid-space hydrocephalus (DESH).

Methods: We evaluated 22 patients (age: 76.4 ± 4.4 y; males: 10, females: 12) and conducted a CSF tap test to determine the surgical indication. CSF concentrations of L-PGDS, Aβ42, Aβ40, and total tau (t-tau) protein were determined using enzyme-linked immunosorbent assays. Clinical symptoms were evaluated by the iNPH grading scale, mini-mental state examination, frontal assessment battery (FAB), and timed up and go test. The extent of DESH was approximated by the callosal angle, and the severity of parenchymal damage was evaluated by the age-related white matter change (ARWMC) score.

Results: L-PGDS and t-tau levels in CSF were significantly decreased in DESH patients compared to non-DESH patients (p = 0.013 and p = 0.003, respectively). L-PGDS and t-tau showed a significant positive correlation (Spearman r = 0.753, p < 0.001). Among the clinico-radiological profiles, L-PGDS levels correlated positively with age (Spearman r = 0.602, p = 0.004), callosal angle (Spearman r = 0.592, p = 0.004), and ARWMC scores (Spearman r = 0.652, p = 0.001), but were negatively correlated with FAB scores (Spearman r = - 0.641, p = 0.004).

Conclusions: Our data support the diagnostic value of L-PGDS as a CSF biomarker for iNPH and suggest a possible interaction between L-PGDS and tau protein. In addition, L-PGDS might work as a surrogate marker for DESH features, white matter damage, and frontal lobe dysfunction.

SUPPLEMENTARY TESTING IN HYDROCEPHALUS

O-030: DANDY’S FORGOTTEN PHENOLSULPHONEPHTHALEIN TEST AND MARMAROU’S INFUSION TEST: BIOPHYSICAL AND HYDRODYNAMIC SIDES OF THE SAME COIN?

David Solomon, Ari Blitz, Daniele Rigamonti

Johns Hopkins University, Baltimore, USA

Background Dandy routinely performed ventricular and spinal subarachnoid injection of phenolsulphonephthalein, a stable, inert dye (Phenol red) currently approved for use in evaluating renal function. After IV injection, phenolsulphonephthalein is rapidly and almost completely eliminated by the kidneys. Quantitative estimation in urine is readily performed and accurate. Transit from CSF occurs via capillaries over the cerebral convexities, with no absorption from the ventricles or through arachnoid granulations. Marmarou’s bolus infusion test is used to calculate CSF outflow resistance by measuring changes in pressure following the addition of a known volume of fluid. We present a historical review of these complementary investigations by these two luminaries.

Methods: Phenolsulphonephthalein for spinal subarachnoid use was prepared as a neutral solution. One ml (6 mg) was diluted with 2 ml of cerebrospinal fluid and injected via lumbar puncture. Clearance from the central nervous system is quantified by determining the amount of dye in the urine. The bolus infusion test involves rapid instillation of 4 ml of artificial CSF into the subarachnoid space, recording the peak pressure and return back to baseline pressure over the course of several minutes.

Results: In the absence of obstruction, phenolsulphonephthalein introduced into the subarachnoid space appeared in the urine in from six to eight minutes with 35-60% excreted in 2h. In communicating hydrocephalus, only 5-10% is excreted in 2h.

Conclusions: Dandy and Marmarou both believed that obstruction of CSF outflow from the subarachnoid space is a critical in the pathophysiology of some types of hydrocephalus. The site(s) of obstruction is now sought using imaging techniques such as cisternography and high resolution MRI. Currently, hydrodynamic tests and models, with their inherent assumptions, attempt to quantify impairment in CSF absorption. Dandy’s phenolsulphonephthalein test is easy to perform and directly measured fluid transfer; it therefore deserves renewed attention.

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O-031: CORRELATION OF ICP MONITORING TO CLINICAL HISTORY IN PATIENTS WITH HIGH OR LOW INTRACRANIAL PRESSURE SYMPTOMS, RELATED TO CSF CIRCULATION.

Patricia Haylock-Vize, Simon Thompson, Chris Kellett, Ahmed Toma, Akbar Khan

Department of Behavioural Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan

Background: Our aim was to evaluate the consistency of CSF circulatory high or low intracranial pressure symptoms and signs determined during clinical history and examination, with actual intracranial pressure (ICP).

Methods: Patients presenting with high or low pressure symptoms were asked to fill in a questionnaire regarding their subjective illness experience and underwent formal clinical history taking and examination. They were then admitted for ICP monitoring, continuously for 48 hours. Mean, compliance and amplitude of ICP were calculated. These results were then correlated with information from the questionnaire, clinical history and clinical findings.

Results: 19 patients were analysed in total. 10 patients had a ventriculo-peritoneal shunt in situ and were admitted with a clinical diagnosis of blocked shunt. 2 patients had lumbo-peritoneal shunt in situ with symptoms indicative of over drainage. 7 patients had presented with orthostatic headaches via our local Headache Neurologists with probable diagnosis of low-pressure headaches. 10 of 19 patients had results conflicting with the symptoms and signs that patients were thought to have presented with. One patient had significant papilloedema confirmed by an ophthalmologist but was found to have normal intracranial pressure recording and his shunt was not revised.

Conclusion: ICP monitoring is an important tool for diagnosis of patients with high or low pressure symptoms as actual intracranial pressure did not consistently correlate to clinical symptoms and signs. ICP monitoring provides accurate diagnosis which helps to improve appropriate decision making in the clinical and surgical management of these patients.

SUPPLEMENTARY TESTING IN HYDROCEPHALUS

O-032: CEREBROSPINAL FLUID BIOMARKERS FOR LONG-TERM TREATMENT OUTCOMES PROGNOSIS IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Madoka Nakajim, Masakazu Miyajima, Ikuko Ogino, Chihiro Akiba, Hajime Arai

Tokyo, Japan

Category: SUPPLEMENTARY TESTING IN HYDROCEPHALUS

Background: The prognosis after Cerebrospinal Fluid (CSF) shunting in iNPH remains uncertain even after the latest establishment of diagnostic criteria and there are few reports on biomarkers related to long-term prognosis. We explored the levels of CSF biomarkers proteins used for outcome prognosis (cognitive and motor function) in shunt treated iNPH cases.

Methods: Thirty-eight patients (13 women; mean age 73.2±SD 6.46 years), with iNPH diagnosis at our institution after the existing guidelines, have undergone lumbo-peritoneal shunting (LPS) ≥ 2 years prior to this study. Postoperative course, representing functional prognosis, was expressed by the modified Rankin Scale (mRS) in two groups regarding effectiveness: effective – improved or unchanged patients with final mRS grade 3 or better, and ineffective. MMSE, FAB, and TMT-A performances 2-6 years after LPS were compared to those before. Shunt reservoir and lumbar CSF biomarkers were also compared. CSF biomarkers included soluble amyloid precursor proteins (sAPP), Amyloid Beta(AB)1-38, AB1-40, AB1- 42，phosphorylated tau (p-tau) and Leucine-rich α2-glycoprotein(LRG). We also measured Lipocalin-type prostaglandin D synthase (L-PGDS)/B-trace, transthyretin (TTR) and cystatin C ; so-called a chaperone of AB protein.

Results: After LPS, iNPH patients showed increased levels of AB1-38, AB1-40, AB1-42, p-tau, L-PGDS and cystatin C levels. In the preoperatively taken samples, there were statistical differences between the “improved” mRS group ( levels of AB1-42 and L-PGDS were 343pg/ml and 12.7 ug/ml ) and the “poor” mRS group ( levels of AB1-42 and L-PGDS of 135pg/ml and 8.0 ug/ml respectively).

Conclusionns: After LPS improved CSF circulation in iNPH, the amount of cystatin C and L-PGDS increased. After AB- variant synthesis switched from AB1-42 to AB1-38, functional prognosis improved.

63 PEDIATRIC I

O-033: TELEMETRIC ICP MONITORING: INITIAL OBSERVATIONS OF CLINICAL AND COST IMPLICATIONS

James Barber

Royal Manchester Children’s Hospital, Manchester, United Kingdom

Background: Management, cost-analysis and early clinical results of using a novel Telemetric ICP monitor in Paediatric patients in the UK.

Methods: Several weeks of Intracranial Pressure Monitoring data was analysed from 4 patients presenting in the last year. 2 Patients diagnosed with complicated hydrocephalus treated with standard Ventriculo-Peritoneal shunting, 1 Patient with Type III Arachnoid Cyst and 1 Patient post Head Injury, have presented with relapsing/remitting signs/symptoms of raised intracranial pressure

Results: 4 Patients to date, were implanted with the parenchymal Raumedic Neurovent P-tel system, enabling ICP monitoring for 3 months, in the first instance ICP monitoring was performed for an average of 5 days. No morbidity to date has been reported. Pathological ICP values could be detected in 2 patients, prompting further neurosurgical intervention. An added benefit observed was the avoidance of admission, on 3 different occasions (as well as the standard protocol of investigations) when two of the patients presented to A+E and were referred with a working diagnosis of shunt malfunction. Additional analysis of these 3 episodes (with cost-extrapolation) highlighted at least 40% potential savings (£18960 vs. £31372 over 19 months)

Conclusions: Overall, the telemetric system was well tolerated and easy to handle by both parents and children. It provides an efficient and cost-effective method of investigation and management of CSF pathology, with low morbidity and higher yield of diagnosis, in comparison with conventional ICP percutaneous monitoring

PEDIATRIC I

O-034: VENTRICULOPERITONEAL SHUNT COMPLICATIONS RELATED TO THE SURGICAL TREATMENT OF SPINAL SCOLIOSIS

Hisashi Hatano1, Noriaki Kawakami2, Taichi Tsuji2, Tetsuya Ohara2, Yoshitaka Suzuki2, Ayato Nohara2, Toshiki Saito2

1Department of Neurosurgery, Japanese Red Cross Nagoya Daiichi Hospital, Nagoya, Japan 2Department of Orthopedics, Meijo Hospital, Nagoya, Japan

Background: Some populations of scoliosis patients are associated with hydrocephalus. Especially most of the patients with myelomeningocele have ventriculoperitoneal shunts. Shunt complications can occur after the surgical procedure of spinal deformity. The purpose of this study was to predict the risk of shunt complications reviewing our experience at one of the largest scoliosis centers in Japan.

Methods: We retrospectively reviewed a single institution’s series of 713 patients with severe spinal deformities under 18 years old at surgery. 1287 surgical procedures were performed between 2006 and 2013.

Results: 36 patients had functioning shunts. 1 mortality case had a history of Dandy-Walker malformation. 6-year-old girl suddenly deteriorated two days after the anterior release and growing rod insertion. She was not able to recover from a shock secondary to uncontrollable intracranial hypertension due to shunt obstruction. 5 patients with myelomeningocele experienced symptomatic shunt malfunction. 3 of them required shunt revisions. 2 of them who were conservatively treated showed fluctuating symptoms related to the positions under halo traction or bed rest after scoliosis correction.

Conclusions: 17% shunt malfunction rate including 3% mortality rate had a significant impact on scoliosis surgery. Shunt length was always concerned before the scoliosis correction and some patients had undergone shunt elongation prior to the admission. We experienced no complication due to the extraction of catheter from peritoneum. Three cases were symptomatic depending on their positions. The ventricular catheters were not in ideal status radiologically in four cases. Neurosurgeons should evaluate the patients’ shunt status carefully prior to their referral to scoliosis surgeons.

64 PEDIATRIC I

O-035: INFANT POST-HAEMORRHAGIC HYDROCEPHALUS (PHH) IN THE UK: IS IT TIME FOR A RANDOMISED CONTROLLED TRIAL?

Bassel Zebian1, Wisam Al-Faiadh2, Florence Hoggs2, Vita Stagno1, Conor Mallucci1, Benedetta Pettorini1, Chris Chandler2, Sanj Bassi2

1Alder Hey Children’s NHS Foundation Trust, Liverpool, United Kingdom 2King’s College London School of Medicine, London, United Kingdom

Background: Despite the decrease in incidence of PHH in the UK, the condition continues to be a significant clinical burden due to the increased survival of premature low birth weight infants. There is a paucity of good quality trials which has resulted in a lack of standardisation of management and a magnification of the challenges presented by the condition. We summarise the various treatment strategies in the UK and review the world literature to assess the feasibility of a multicentre randomised trial.

Methods: A questionnaire was circulated to the members of the British Paediatric Neurosurgery Group (BPNG) and the responses were analysed and summarised.

Results: Of 20 respondents from 14 units, 40% used reservoirs, 30% trans-fontanelle taps, 15% ventriculo-subgaleal shunts and 10% LPs. EVDs were only used by 15% if the primary temporising measure failed. 30% specified a minimum age before permanent CSF diversion and 80% a minimum weight (range 1-3kg). 85% opted for a VPS as the definitive diversion and 15% opted for an ETV. 55% treated 5 or more patients a year and 30% treated 10 or more. 85% respondents would consider taking part in a prospective trial of the commonest temporising procedures and 75% were prepared to randomise patients to different treatment arms.

Conclusions: PHH continues to be a significant clinical challenge for neurosurgeons in the UK. Its management varies between clinicians. There seems to be willingness in the UK to partake in a RCT to establish best practice.

PEDIATRIC I

O-036: UNRECOGNIZED HYDROCEPHALUS AS A RISK FACTOR FOR CSF LEAK AND WOUND BREAKDOWN FOLLOWING IMPLANTATION OF INTRATHECAL BACLOFEN PUMP

Brian W Hanak, Luke Tomycz, Robert Oxford, Erin Hooper, Samuel Browd

University of Washington, Seattle, WA, USA

Background: Intrathecal baclofen (ITB) is one of the most effective treatments for spasticity and dystonia associated with cerebral palsy. However, complications of ITB pump implantation continue to be unacceptably high with a combined risk of infection and malfunction exceeding 40%. We theorize that intracranial hypertension promotes cerebrospinal fluid (CSF) leakage, increasing the risk of wound breakdown and infection following pump implantation.

Methods: The case series is a retrospective review of 16 patients considered for ITB pump implantation between September 2013 and March 2014 at our institution. Patients were deemed pump candidates after being evaluated by both rehabilitation medicine and neurosurgery. Cranial imaging was performed on all patients preoperatively to evaluate ventricular size and configuration. Prior to ITB pump implantation a sedated lumbar puncture was performed. If the CSF opening pressure was greater than 21 cmH2O, we would only offer ITB pump implantation at a later date following a CSF diversion procedure.

Results: Ultimately 16 patients ranging in age from 4-20 met criteria for inclusion in the study. Among this population, 6/16 (37.5%) had intracranial pressures in excess of 21 cmH2O. There was a mild positive correlation between pre-operatively measured frontal and occipital horn ratios on cranial imaging and measured opening pressures by lumbar puncture (R2 = 0.073). 10/16 (62.5%) patients ultimately underwent ITB pump implantation and there were no post-operative complications in this group. Two patients ultimately received ventriculoperitoneal shunts. One patient with epilepsy had a significant reduction in seizure frequency following shunt placement. No cognitive improvements were noted in follow-up with either patient.

Conclusions: Our data supports the notion that intracranial hypertension raises the risk of CSF leak following ITB pump implantation and highlights the high rate of hydrocephalus in the cerebral palsy population. We present a strategy for mitigating the rate of complications from this valuable procedure.

65 NEURORADIOLOGY II

O-037: WATER TURNOVER IN BRAIN PARENCHYMA AND VENTRICLES ESTIMATED BY DYNAMIC PET USING H215O

Mitsuhito Mase1, Emi Hayashi2, Kiminori Aoyama1, Hiroshi Yamada,1 Akihiko Lida2, Toshiaki Miyati3, Etsuro Mori4, Kazuo Yamada1

1Department of Neurosurgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan 2Department of Radiology, Nagoya City Rehabilitation Center, Nagoya, Japan 3Faculty of Health Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 4Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University School of Medicine, Sendai, Japan

Background: Many studies are ongoing to reconsider cerebrospinal fluid (CSF) physiology including its formation and absorption by using tracers. However, the movement of the tracer is not identical to the movement of water. In order to clarify the origin and turnover of water molecules in CSF, dynamic PET (positron emission tomography) study was performed using radio labeled H2O.

Methods: Eight normal volunteers (mean 63 years) were included. Dynamic PET data were obtained for 8 minutes after intravenous bolus injection of 5ml of saline including H215O (mean 880MBq). Regions of interest (ROI) were automatically set in the internal carotid artery (ICA), superior sagittal sinus (SSS), choroid plexus (CP), cerebral gray matter (GM), white matter (WM), and lateral ventricle (LV) based on the signal intensities of T2 weighted MR images. The time and relative radio activity curves of each ROI were analyzed.

Results: The maximum peak radio activities of GM and WM were at 25 and 135 seconds after the peak in ICA, respectively. At that time, the relative peak activities of GM and WM were 73 and 57% of the ICA peak activity, respectively. The activities of GM and WM decreased gradually. On the contrary, the activity of LV increased gradually until the end of the measurement {14% of the ICA peak activity, 27% of brain parenchyma (GM+WM) activity at 7 minutes}. The activity of the ICA after the first peak was nearly same as the activity of SSS. The activity curve of CP was nearly parallel and the level was 80% of brain parenchyma, which was larger than the level of SSS.

Conclusion: The present study showed very fast movement of water molecules from artery to brain parenchyma and ventricular CSF. However, it cannot be concluded whether water molecules in the CSF come from brain parenchyma or choroid plexus.

NEURORADIOLOGY II

O-038: THREE-DIMENSIONAL VISUALIZATION OF VIRCHOW–ROBIN SPACES WITH 3-T MAGNETIC RESONANCE IMAGING

Masatune Ishikawa, Shigeki Yamada

Otowa Hospital, Kyoto, Japan

Background: Virchow–Robin spaces (VRS) are cerebrospinal fluid-filled spaces that surround penetrating arterioles and communicate with extensions of the subarachnoid space. VRS might play important roles in regulating fluid movement and drainage in the central nervous system and in immunoregulation. However, their functional roles in hydrocephalus remain unclear. To investigate their functional roles in patients with hydrocephalus, VRS were visualized using a three-dimensional- constructive interface steady state (3D-CISS) sequence for 3-T magnetic resonance imaging (MRI).

Methods: 3-T MRI with 3D-CISS was performed for five cases with definite idiopathic normal pressure hydrocephalus (iNPH), 10 possible cases of iNPH, and 12 controls with various disorders. The axial source images were semi-automatically reconstructed by 3D volume rendering and multi-planar reformatting with a VINCENT workstation. VRS were defined as tubular structures of various diameters on the CISS images.

Results: Excellent visualization of VRS was achieved using 3-T MRI with 3D-CISS compared to T2-weighted 1.5-T MRI. Most VRS were observed in the basal ganglia and white matter near the lateral ventricle. Some VRS in the basal ganglia coincided with the course of the lenticulostriate arteries. The VRS in the basal ganglia directly communicated with the basal cistern, and some extended to the ventricular floor. The VRS in the white matter did not communicate with the subarachnoid spaces. They started just caudal to the cortex and ran down toward the superolateral angle of the lateral ventricle. Many VRS were observed in high-convexity white matter, but few were observed in the frontal and temporal areas. Most patients with possible iNPH and other disorders showed abundant VRS in both the basal ganglia and white matter, while most patients with definite iNPH showed fewer visualization of VRS.

Conclusion: 3-T MRI with 3D-CISS clearly demonstrated VRS, and the functional roles of VRS can be investigated using this technique.

66 NEURORADIOLOGY II

O-039: STOMA CLOSURE AFTER PRIMARY ETV FOR OBSTRUCTIVE HYDROCEPHALUS Eric Sankey1, Ignacio Jusue-Torres1, Jamie Hoffberger1, Ari Blitz2, Daniele Rigamonti1

1Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA 2Division of Neuroradiology, The Russell H. Morgan Department of Radiology and Radiologic Science, The Johns Hopkins Hospital, Baltimore, USA

Background: CISS MRI aids clinicians in both the pre and postoperative evaluation of CSF flow patterns and postoperative ventriculostoma patency. In this study, we evaluate the rate of stoma closure after primary ETV for obstructive hydrocephalus followed with CISS MRI.

Methods: We retrospectively reviewed the clinical and radiographic data of 151 consecutive patients, treated between 2007 and 2013, with ETV for hydrocephalus. Sixty ­seven patients were excluded: 12 with communicating hydrocephalus and 55 with previous shunting. Eighty-four patients treated with a primary ETV for obstructive hydrocephalus were included. Follow- up duration was 9 (2-25) months. Thirty ­nine (46%) patients were male and 45 (54%) were female, aged 52 (41­65) years at treatment. Clinical outcome was reported as a percentage of improvement/worsening of the presenting symptoms. ETV patency was assessed by CISS MRI. Continuous data are summarized using medians and inter-quartile ranges.

Results: Stoma closure occurred in 5 patients (6%) during follow­-up, all of whom required revision via shunt (n=3) or repeat ETV (n=2) after failure. Time to closure was 5 (4­9) months. At last follow-up, 4 of these patients, including both with repeat ETV, improved and 1 worsened, both clinically and radiographically. CISS MRI verified stoma occlusion by Liliequist’s membrane in 1 patient; the cause of closure of the 4 remaining patients could not be determined.

Conclusions: ETV success largely depends on careful patient selection, preoperative planning, and intraoperative evaluation of potential complications. Stoma closure occurs at a relatively low rate (6%). Factors that can potentially lead to subsequent stoma closure/obstruction include: small stoma size, thickened third ventricular floor, nearby gliotic tissue, and floating arachnoid membrane tissue (e.g. Liliequist’s membrane).

NEURORADIOLOGY II

O-040: FINITE ELEMENT ANALYSIS ON PERIVENTRICULAR LUCENCY IN HYDROCEPHALUS: EXTRAVASATION OR TRANSEPENDYMAL CSF ABSORPTION?

Hakseung Kim1, Eun-Jin Jeong1, Dae-Hyeon Park1, Byung C Yoon2, Kiwon Kim3, Marek Czosnyka4, Dong-Joo Kim5

1Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea. 2Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, 3Department of Rehabilitation medicine, Seoul National University children’s Hospital, College of Medicine, Seoul, South Korea.USA 4Department of Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom. 5Korea University, Seoul, South Korea

Background: The periventricular lucency (PVL) is a common radiological finding of hydrocephalic patients. Up to this date, the physiology behind this phenomenon is unclear. Currently there are two major hypotheses explaining the PVL; the extravasation of ventricular cerebrospinal fluid (CSF) into the periventricular region, or the transependymal CSF absorption. Nonetheless, no decisive evidence exists for either of the two theories.

Methods: A finite element brain model was constructed to investigate possible mechanism of PVL in hydrocephalus. Geometrical details (e.g., sulci, grey and white matter, falx cerebri and skull) were implemented by using MR image. The initiation and development of hydrocephalus were modelled by inducing increase in transmantle pressure gradient (TPG). The model was exposed to varying degree of TPG, to investigate the effects of different geometrical characteristics on the distribution of PVL. The degree and distribution of PVL were assessed by measuring pore pressure (pressure of fluid filling the pore space).

Results: The model successfully simulated ventriculomegaly and PVL. The extent of PVL was prominent in mild to moderate ventriculomegaly. As the degree of ventricular deformation exceeds certain points, the pore pressure across the entire parenchymal area became positive, thus inducing the disappearance of PVL.

Conclusions: The results are in accordance with common clinical findings of PVL. The degree of ventriculomegaly affects heavily on the development of PVL; however, the two were not in linear relationship. The results are indicative of the transependymal CSF absorption, but the extravasation theory cannot be completely rejected.

67 NEURORADIOLOGY II

O-041: CSF OSCILLATIONS INTEREST IN HYDROCEPHALUS PATIENTS Cyrille Capel1, Marc Baroncini2, Jérome Hodel3, Anthony Fichten1, Xavier Leclercq3, Olivier Balédent4

1Neurosurgery, Amiens, France 2Neurosurgery, Lille, France 3Radiology, Lille, France 4Image Processing Department, Amiens, France

Background: Adults’ hydrocephalus is related to CSF flows disorders. Phase contrast MRI (PC-MRI) is the unique tool to measure CSF oscillations in vivo during the cardiac cycle. CSF oscillations are a controversial point on hydrocephalus diagnosis. The aim is to evaluate CSF oscillation interest in hydrocephalus patients’ candidate to shunt.

Methods: 100 patients with ventricular dilation and clinical symptoms associated with Hakim triad, suspected to present active hydrocephalus, are included in a prospectively research project. In addition to traditional clinical practice, all patients underwent PC-MRI sequences to evaluate CSF oscillations and were followed for at least 6 months after MRI (or and surgery) before final diagnosis. 39 were excluded because of follow-up<6 months; 12 patients presented aqueductal stenosis; 26 patients with a final diagnosis, confirmed by 6 months follow up, excluding active hydrocephalus and then surgery, were included as control group (CG) and 23 patients who have improved after shunt placement with a grade 0 or 1 on Stein and Langfitt Scale for assessment of shunt outcome were included in hydrocephalus shunt responders group (SRG). Stroke volumes were calculated in microlitres per cardiac cycle, in the aqueduct (SVaqu) and into the cervical (C2C3) spinal subarachnoid spaces (SVspine). CSF ratio was defined as SVspine/SVaqu.

Results: SVaqu was higher in SRG (225±129μL/cc) than in CG group (90±83μL/cc) (p=0.002). SVspine was not different between SRG (485±250μL/cc) and CG (546±275μL/cc) (p=0,46). CSF ratio was smaller in SRG (2.7±1.9) than CG (10.2±11.9) (p=0.047).

Conclusions: CSF dynamic disorders in SRG were mainly due to intraventricular CSF dynamic alteration nevertheless SVaqu in few cases remain normal. High SVaqu is an additional argument for selectect patient for shunt, but a low SVaqu alone should not formally challenge the indication of shunt.

NEURORADIOLOGY II

O-042: THE RELATIONSHIP BETWEEN CSF OSCILLATIONS, CEREBRAL VASCULAR PULSATIONS AND BRAIN MORPHOLOGY

Bader Chaarani1, Jadwiga Zmudka1,2, Roger Bouzerar1, Olivier Balédent1

1University Hospital of Amiens, France 2University of Picardy, Amiens, France

Background: According to hydro and hemodynamic studies, cerebrospinal fluid (CSF) oscillations may depend on ventricular morphology and, to a large extent, on the vascular pulsations. However, the complete understanding of CSF dynamics remains a challenge. Hence, in this work, we studied the relationship between CSF oscillations, brain morphology and vascular pulsations under physiological conditions.

Methods: 20 healthy elderly (mean age 69±8) underwent axial 3D T1 and phase-contrast MRI (PCMRI) acquisition with a 3T MRI scanner. Ventricular (CSFv) and subarachnoid (CSFs) CSF volumes were calculated from 3D morphological images. Dynamic PCMRI data were acquired to measure the stroke volume corresponding to the displaced CSF volume during a cardiac cycle (CC) at the aqueductal (ASV) and C2-C3 cervical (CSV) levels. Intracerebral PCMRI were also acquired to assess the arteriovenous pulsations calculated from internal carotids, basilar artery, sagittal and straight sinuses. ASV and CSV were also normalized with the CC duration.

Results: Mean±SD volumes were 26 ± 11 mL for CSFv and 99 ± 24 mL for CSFs. Mean±SD ASV was 56 ± 29 uL/ CC, CSV was 444 ± 240 uL/CC and the arteriovenous pulsations was 1 ± 0.27 mL/CC. No relationship was observed between ASV and CSV on one hand and CSFv and CSFs on the other (p>0.05). The arteriovenous pulsations was not correlated with ASV or normalized ASV. Nevertheless, it was slightly correlated with CSV (p<0.05) and this relationship was more important with normalized CSV (p<0.001).

Conclusions: In healthy subjects, the CSF oscillations at the cervical and aqueductal levels do not depend on ventricular or subarachnoid morphology. The CSF oscillations at the cervical level are essentially regulated by the vascular pulsations and the CC duration.

68 NEURORADIOLOGY II

O-043: SHUNT SERIES, ARE THEY ESSENTIAL? Wai Cheong Soon, Ibrahim Djoukhadar, Jamie Clarke, Osamu Iizuka, Jeremy Macmullen-Price

Imperial College NHS Trust, London, United Kingdom

Background: Ventriculo-peritoneal (VP) shunts took their origins from 1881, when Wernicke created a sterile ventricular puncture with an external CSF drainage system. Despite improvements of the shunt systems over the years, they can still malfunction. Radiology plays a major role in the management of patients with suspected VP shunt malfunction. This study aims to review the role of shunt series (SS) radiographs in the assessment of patients with suspected VP shunt malfunction.

Methods: Shunt series radiographs performed over 49 months between January 2007 and June 2011 with their corresponding CT reports were extracted from the local radiology information system and reviewed retrospectively.

Results: A total of 705 shunt series were performed in 350 patients. 395 and 310 studies were performed in the adult and paediatric age groups respectively. The total rate of shunt revision is 16% (113/705). There was no significant difference in the shunt revision rate between adult (15.6%) and paediatric (16.4%) age groups. The percentage of shunt revision in cases with an abnormal SS is 22.1% (25/113). Of these, shunt revisions were performed in only 10 out of 113 (8.8%) patients for whom; the sole radiological abnormality was an abnormal SS. Conversely, shunt revisions were performed in 56 patients (49.6%) with abnormal CT head as the sole radiological abnormality. Shunt revisions were performed in 15 patients (13.3%) where both the shunt series and CT head were abnormal. In the remaining 32 patients (28.3%) who underwent shunt revisions, there was no radiological abnormality.

Conclusions: Shunt series radiographs have a role in assessing VP shunt malfunction. However, given the low yield of shunt series [1.4% (10/705) as the sole radiological abnormality in patients undergoing surgical intervention] and the radiation burden, we believe it is best used following clinical evaluation and cross-sectional imaging in patients undergoing shunt revision.

NEURORADIOLOGY II

O-044: CONGENITAL CHRONIC COMMUNICATING HYDROCEPHALUS WITH WIDE FORAMEN OF MAGENDIE AND DILATION OF CISTERNA MAGNUM: CLINICAL FEATURES AND CONGENITAL ETIOLOGIES

Hiroshi Kageyama1, Ikuko Ogino1, Ryoko Fukai2, Noriko Miyake2, Kenichi Nishiyama3, Naomichi Matsumoto2, Hajime Arai1, Masakazu Miyajima1

1Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan 2Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan 3Brain Research Institute, University of Niigata, Niigata, Japan

Introduction: We followed up some familial and sporadic patients of chronic communicating hydrocephalus with wide foramen of Magendie and dilation of cisterna magnum. The purpose of this study is clinical and genetic analysis of this type of hydrocephalus.

Methods: Clinical and imaging studies were retrospectively performed. Eight patients in three families and seventeen sporadic patients, including three children, were participated. Tetra-ventricular dilatation, opening of aqueduct, and wide foramen of Magendie with dilation of cisterna magnum, are essential image findings for diagnosis. In some cases, time- spatial labeling inversion pulse examinations were also done for analysis of cerebrospinal fluid flow. Genetic analysis was performed to detect the pathogenic copy number variations (CNV) using high resolution microarray. The detected CNVs were validated by quantitative PCR and breakpoint sequencing. The expression of the candidate gene was evaluated by immunostaining for the autopsied brain tissue of unaffected individuals.

Results: In adult cases, age of onset (57.6 years) was lower than that of idiopathic normal pressure hydrocephalus (iNPH). Clinical symptoms resembled those of iNPH. All three infantile patients exhibited macrocranium. Patients, especially with downward bulging of the 3rd ventricular floor, could be cured with both lumboperitoneal shuning and endoscopic third ventriculostomy, despite imaging evidences as communicating hydrocephalus. Genetic analysis revealed a copy number loss, not registered in a public copy number data base (Database of Genomic Variants), only in patients of a family. With immunostaining, the gene was strongly expressed in choroid plexus epithelial cells and ependymal cells.

Conclusion: Chronic communicating hydrocephalus with wide foramen of Magendie may belong to a new subtype of hydrocephalus with congenital etiology. According to genetic and immunohistochemical studies, a gene mutation can cause this type of hydrocephalus, associated with pathophysiological kinetic changes of cerebrospinal fluid.

69 SHUNT DESIGN

O-045: LABORATORY TESTING OF MICRO-ROBOTIC SELF-CLEANING VENTRICULAR CATHETER

Marek Czosnyka1, Zofia Czosnyka1, Joseph Donnelly1, Simon Sharon2, Yossi Porat2, Moshe Shohan2, Harel Gadot2, Or Samooha2

2Cambridge Shunt Evaluation Lab, Neurosurgical Division, Cambridge University Hospital, United Kingdom 2Microbot Medical Ltd, Israel

Background: Blockage or partial obstruction of the ventricular catheter is a frequent problem limiting the functionality of contemporary CSF shunts. In the Cambridge Shunt Evaluation Laboratory we tested a prototype micro-robotic ventricular catheter (SCS – designed by Microbot Medical Ltd, Israel) containing an internal cleaning mechanism dedicated to prevent ventricular catheter obstruction from either in-growing choroid plexus or other CSF debris. The aim of this study was to evaluate flow rate and flow hydrodynamic of this novel device while connected to popular types of adjustable shunts.

Method: Three samples of SCS provided by the manufacturer were tested in the laboratory. Activated and deactivated ventricular SCS catheters were first tested alone (pressure-flow performance, hydrodynamic resistance) and then connected to fresh Strata, ProGav and Codman Hakim hydrocephalus shunts with and without standard distal peritoneal drains, as supplied by the manufacturers. Pressure-flow tests were performed to evaluate operating pressures and hydrodynamic resistances of the shunt system connected with SCS and connected with the standard ventricular catheters.

Results: The hydrodynamic pressure-flow performance characteristics of the SCS were linear, showing low hydrodynamic resistance both with and without activation of the internal cleaning mechanism (0.67+/-0.12 vs. 0.61 +/-0.1 mmHg/(ml/min); p<0.1). This value was slightly lower than in majority of standard ventricular drains (0.9-1.2 mmHg/(ml/min)). Changes in ambient temperature (from 30 to 40oC) did not change hydrodynamic performance of the SCS. Performance of the three most popular adjustable valves did not differ when working with SCS in comparison to standard ventricular catheters. Resistances of opened valves remained constant, and operating pressures were in general decreased but insignificantly, by less than 0.12 mm Hg (p<0.05). Pulse amplitude of inlet pressure (up to +/- 5mm Hg, 1Hz) did not reveal any differences in shunt functioning.

Conclusion: Microbot Medical SCS presents low hydrodynamic resistance. The SCS behaves as a standard ventricular catheter and does not change the hydrodynamic performance of adjustable hydrocephalus valves.

SHUNT DESIGN

O-046: PROPOSAL OF A NEW GRAPH FOR SHUNT PERFORMANCE

Angelo Maset1, Gustavo Botelho1, Lucas Meguins1, Rodrigo Pinhabel1, Bruna Mancini2, Jose Andrade2, Sergio Ramin1, Dionei Moraes1.

1FUNFARME Sao Jose do Rio Preto, Brazil 2Ventura Biomedica Ltda

Background: The hydrokinetic parameters as gravitational height and intra-abdominal pressure are considered today predominant physical forces for an adequate flow through a shunt. Additionally, there are considerable changes in the shunt hydrodynamics when original shunt dimensions are changed upon shunt implantation. The current pressure x flow characteristics displayed at Instructions for use brochures are useless, and do not consider forces above. We propose a new diagram which would provide such information.

Methods: A 0,76 mm I.D LP shunt was submitted to bench tests according to ISO 7197. Shunt was submitted to gravitational heights (H) of 0, - 50, – 100, -150, and – 300 mm at lengths of 800, 700, 600, 500 and 400 mm. Each test was repeated 5 times. Results were displayed in a chart which considers the resistance (pressure in mmH20) in the vertical bar versus the estimated difference in height between proximal and distal tips of the implanted catheters, at the physiological flow rate of 20 ml/hr.

Results: As expected, shunt lost resistance as the catheter length decreased and as gravitational forces increased. For an 800 mm shunt, at H = 0 mm resistance was 71 mmH2O. At H= - 300 mmH2O, resistance was - 141 mmH2O. For a 500 mm LP shunt, at H = 0 mm resistance was 40 mmH2O. At H= -300 mm, resistance was – 141 mmH20. Graphs also demonstrate changes in resistance as the catheter is decreased in its length.

Discussion: There is a need for a chart that would better minimally represent the changes in the intracranial pressure occurring during postural movements in a given individual with an implanted shunt. A pressure x H at 20 ml/hr perhaps would be more informative to the neurosurgeon than the classic pressure x flow graph, and it might complement the existing one.

70 SHUNT DESIGN

O-047: RESURRECTION OF THE PUMPING TEST FOR OBSTRUCTION ? – EVALUATION OF A NEW FLUSHING RESERVOIR FOR SHUNTING OF HYDROCEPHALUS

Christian Sprung1, Thoralf Knitter2, Hans-Joachim Crawack2

1Neurosurgical Clinic, Charité, Universitätsmedizin Berlin, Germany, 2Methke GmbH, Potsdam, Germany

Background: There is international agreement that a reservoir should be integrated in shunts for easy access to cerebrospinal fluid (CSF) and the measurement of pressure. Although the majority of neurosurgeons also favour to evaluate shunt-function by the possibility to flush the reservoir, the reliability of this purpose is doubted in literature. A new flushing-device has been developed and its advantages and drawbacks are evaluated in this study to settle this controversy.

Methods: The new tool is a flushing reservoir constructed with a sapphire-ball in a cage as a non-resistance valve. In a test rig, its volume per digital compression, resistance to flow and the power of suction have been measured in vitro. Finally we evaluated the theoretical advantages in vivo after implantation of a consecutive series of 360 reservoirs, assessing clinical complications and drawbacks.

Results: The volume of CSF per compression of 0.28ml proved favourable in comparison to other devices for pumping. The reservoir-resistance to CSF flow of ≤ 1cm of H2O was negligible. With -88 mmHg the power of suction was determined similar to other reservoirs and valves. After implanting more than 500 of these reservoirs we did not register more than 3 mechanical complications. Total occlusion of the ventricular catheter could be assessed with high certainty. The detection of an obliteration of the proximal peritoneal catheter is also possible. The distal portion of the latter and partial obstructions are still difficult to diagnose, but we assessed a sensitivity of 79% and a specificity of 97% with this reservoir.

Conclusions: Several parameters of the reservoir are obvious advantageous when compared to other flushing devices, thus with this reservoir it is more reliable to determine obstructions of the shunt. Because of our clinical results with this reservoir we believe in a revival of the flushing test at least in adults.

SHUNT DESIGN

O-048: SHUNTS FOR HYDROCEPHALUS: REVISITING SOTELO’S CONCEPT

Angelo Maset, Gustavo Botelho, Lucas Meguins, Rodrigo Pinhabel, Bruna Mancini, Jose Camilo, Sergio Ramin, Dionei Moraes

Funfarme, S J Rio Preto, Brazil

Background: Over-drainage and under-drainage continue to be the most common dysfunctions for shunt implantation. The trend has been for sophisticated valve mechanisms. Sotelo postulated that the hydrokinetic parameters of shunts might be inadequate, and proposed a shunt consisted of a tubing with specific dimensions which would allow free flow according to the physiology. This paper reviews his theoretical considerations under the light of the current european normatization for shunt manufacturing.

Methods: We evaluated a shunt tubing according to Sotelo’s original setting (ID 0,51 mm x 800 mm). First, shunts were tested using the extremes of Sotelo’s methodology. Later, we tested normative ISO 7197, applying flows at 5,10,20,30,40 and 50 ml/hr), and heights H=0, H= - 150, H= - 300, and H= - 500 mm

Results: Using Sotelo’s methodology, our results matched his. For ventricular pressure at 20 cm H20 and siphon effect at 0 cm H20, we found 12,8 ml/hr (against 13,4 ml/hr); for ventricular pressure at 0 cm H20 and siphon effect at – 50 cm H20, we found 34,8 ml/h (against 33,5 ml/hr). During the simulation of a patient in the horizontal position e flows set at 5,10,20,30,40 and 50 ml/hr, resistance profile for the tubing was much higher than a normal shunt. For flows at 20 ml/hr, average pressure was 228 ± sd 7 mmH20 at H=0 mm; at H=- 300 mm, average pressure was 29,8 ± sd 15,8 mmH20; at H=- 500 mm, average pressure was – 210,0 ± sd 7,6 mmH20.

Conclusions: Pressure-flow values for a 0,51 mm I.D shunt was much more resistive than a traditional shunt. Interestingly, at lower flow rates, the catheter behaved it similar to regular shunts. Flow rates were within reasonable values for most negative gravitational heights. However, in real life the internal diameter may be a problem for shunt survival.

71 SHUNT DESIGN

O-049: CONTROLLING ICP THROUGH AUTOMATED FEEDBACK CONTROL

Kalyan Raman

Northwestern University, Evanston, USA

Background: Hydrocephalus is treated by implanting a shunt to reduce ICP by draining excess CSF from the brain to another part of the body, such as the peritoneum or heart. Existing shunts are connected to valves which work like all-or-none devices. Opening these valves induces drainage of cerebrospinal fluid (CSF) through the shunt at a high rate and closing them shuts off drainage completely. These on-off shunts function like simple on-off switches and cannot provide continuous controlled CSF drainage to keep the patient’s ICP on the clinically desired path over time.

Methods: The Marmarou model relating the temporal evolution of ICP in pressure-volume studies to infusions incorporates observed fluctuations in the ICP through a nonlinear differential equation (SDE). Using this model as the mathematical basis, nonlinear control theory methods are used to design an automatic feedback controller for ICP regulation.

Results: Nonlinear control theory provides the controller for automatic ICP regulation through feedback provided by measurement of the ICP as a closed-form solution. The implementation of this algorithm ensures that if the ICP is not initially on the clinically desirable trajectory, then it will converge to it exponentially fast, thereby assuring rapid regulation of the patient’s ICP. Even when uncontrolled disturbances are present, the controller converges to the clinically desirable trajectory for ICP exponentially fast on average.

Conclusions: The non-linear feedback control system improves shunts used in the treatment of not only hydrocephalus, but also other conditions such as, for example, traumatic brain injury, in which regulation of the patient’ ICP is critically important. Basic shunt technology has not changed much over time—thus the controller developed in this research elevates the sophistication level of the treatment of diseases and conditions that require careful ICP regulation.

SHUNT DESIGN

O-050: IN VITRO CHARACTERIZATION OF SIX TYPES OF ANTI-SIPHONING DEVICES

Florian Freimann1, Takaoki Kimura2, Veit Rohde1, Ulrich-Wilhelm Thomale3

1Department of Neurosurgery, University Medicine Göttingen, Georg-August University, Göttingen, Germany 2Department of Neurosurgery, Juntendo University School of Medicine, Tokyo, Japan 3Division of Pediatric Neurosurgery, Charité – University Medicine Berlin, Germany Background: There is a growing evidence that supports the augmentation of adjustable differential pressure valves with anti-siphon devices (ASD) to overcome overdrainage of CSF. No comparative data are available yet on the performance of different types of ASDs. We aimed to provide in vitro data on the pressure and flow characteristics of six different types of ASD (both flow- and gravity-depending) in order to improve the understanding of those devices.

Methods: We analyzed three gravity-depending ASD (Shuntassistant [SA], Miethke; Gravity Compensating Accessory [GCA], Integra; SiphonX [SX], Sophysa) and three flow-depending ASD (Siphonguard [SG], Codman; Delta Chamber [DC], Medtronic; Anti-Siphon Device [AS], Integra) regarding their flow and pressure characteristics. Defined conditions of differential pressure within a simulated shunt system were generated (intracranial pressure [ICP] 0 to 40cmH2O, siphoning 0 to -40cmH2O). Flow and pressure characteristics of each device were measured. Additionally, the gravity-depending ASD were measured in seven defined spatial positions (0-90°).

Results: The flow characteristics of the three gravity-assisted ASD depended basically on the differential pressure and their spatial position. All three devices were able to reduce the siphoning effect but with different extent (flow at ICP: 10cmH2O, siphoning 20cmH2O at 0°/90°: SA: 7.1±1.2*/2.3±0.5*ml/min; GCA: 10.5±0.8/3.4±0.4*ml/min; SX 9.5±1.2*/4.7±1.9*ml/ min compared to control: 11.1±0.4ml/min [*p<0.05]). In contrast, the flow characteristics of the flow-regulated ASD were mainly depending on the ICP and less on the varying siphoning effects (flow at 10cmH2O, siphoning 0cmH2O/ siphoning 20cmH2O: DC: 2.6±0.1/ 4±0.3*ml/min; AS: 2.5±0.2/ 0.8±0.4*ml/min; SG: 0.8±0.2*/ 0.2±0.1*ml/h compared 2.8±0.2/ 11.1±0.4ml/min [*p<0.05]), which varied significantly among the devices.

Conclusion: The investigated ASD controlled the siphoning effect within a simulated shunt system to different degrees. The augmentation of adjustable differential pressure valves with ASD still seems to be appropriate, but comparative trials are needed in the future to answer which type of devices are superior.

72 EXPERIMENTAL HYDROCEPHALUS

O-051: THE POSITION-DEPENDENT INTRAPERITONEAL PRESSURE IN A LARGE ANIMAL MODEL

Florian Freimann, Veit Rohde, Christian Sprung, Stefan Wolf

Department of Neurosurgery, University Medicine Göttingen, Georg-August University, Göttingen, Germany

Background: The flow of CSF in ventriculoperitoneal shunts depends on the differential pressure between the intracranial and the intraperitoneal cavity. The determination of the intraperitoneal pressure (IPP) can be therefore relevant for the choice of the appropriate valve type and pressure setting.

Methods: Two custom made telemetric pressure probes (Raumedic, Helmbrechts, Germany) were implanted intraperitoneally in the ventral midline of female pigs with a distance of 30 cm (n=6, German landrace; mean body weight 59.5 ± 18.4 kg). Results were referenced with conventional non-invasive pressure measurements (intra-vesical and intra-gastral). IPP was measured on following three time points under defined body positions, starting in supine position at 0° and increasing to 30°, 60° and 90° (=vertical) body position. Radiographic control (CT) was performed post mortem in order to measure distance between the probe tips and their intraperitoneal placement.

Results: Reproducible results for all positions were obtained. The epigastrally placed telemetric probe revealed an IPP of 6.7(±1.8)cmH2O at 0° (supine), of 6.7(±2.3)cmH2O at 30°, of 5.3(±1.9)cmH2O at 60° and of 3.8(±1.9)cmH2O at 90° (vertical body position). The probe placed in the lower abdomen showed an IPP of 12.2(±2.2)cmH2O at 0°, of 18.2(±2.3) cmH2O at 30°, of 24.1(±2.3)cmH2O at 60° and 29.4(±2.6)cmH2O at 90° (vertical body position). The distance between probes in vertical direction (“epigastral implanted” over “lower abdomen implanted”) was determined as 3, 11, 18 an 21 cm for 0°, 30°, 60° and 90° position after radiographic control.

Conclusion: The IPP is able to reduce the differential pressure in ventriculoperitoneal shunted patients. The IPP depends largely on the intraperitoneal acting hydrostatic pressure. Our data support the choice of a low valve opening pressure for the horizontal body position.

EXPERIMENTAL HYDROCEPHALUS

O-052: CORRELATIONS BETWEEN NEUROLOGICAL DEFICITS AND THE SEVERITY OF VENTRICULOMEGALY IN EXPERIMENTAL INFANTILE HYDROCEPHALUS

James McAllister1, Michael Williams2, Amanda Braun2, Robyn Amos-Kroohs2, Diana Lindquist3, Francesco Mangano3, Charles Vorhees2, Weihong Yuan3

1Washington University School of Medicine, St. Louis, MO, USA 2Division of Neurology, Cincinnati Children’s Research Foundation, Cincinnati, OH, USA 3University of Cincinnati College of Medicine, Cincinnati, OH, USA

Background: The pathogenesis and the significance of long-term neurological deficits in pediatric hydrocephalus are difficult to identify, in part because of variable ventriculomegaly observed both in patients and experimental models.

Methods: To correlate behavioral outcome with the severity of ventriculomegaly, rats received percutaneous intracisternal injections of kaolin to induce obstructive hydrocephalus or saline for controls on postnatal day (P)21. Locomotor activity, acoustic startle with prepulse inhibition (PPI), and Morris water maze (MWM) performance were tested on P28 and P42, 7- and 21-days post-kaolin, respectively. Animals were analyzed in subgroups based on Evan’s ratios (ER, from MRI scans) at the end of testing to create 4 subgroups from least to most severe: ER 0.4-0.5, 0.51-0.6, 0.61-0.7 and 0.71-0.82.

Results: Kaolin-treated animals weighed significantly less than controls at all times. Differences in locomotor activity occurred at P42 but not P28. On P28 there was an increase in prepulse inhibition for all but the least severe kaolin-treated group, but no difference at P42 compared with controls. In the MWM at P28, all kaolin-treated groups had longer path lengths to the platform than controls, but comparable swim speeds. Probe trial performance was worse in all kaolin-treated animals except the least severe. On P42, only the most severely affected kaolin-treated group showed deficits compared with control animals. This group showed no MWM learning and no memory for the platform position during probe trial testing. Swim speed was unaffected, indicating that motor deficits were not responsible for impaired learning and memory.

Conclusions: These findings indicate that kaolin-induced ventriculomegaly in rats interferes with cognition regardless of the final enlargement of the cerebral ventricles, but final size critically determines whether lasting locomotor, learning, and memory impairments occur.

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O-053: THE DISTRIBUTION KINETICS OF IRON TAGGED DEXTRAN IN HYDROCEPHALUS IS DIFFERENT FROM THAT IN NORMAL (UNAFFECTED) RATS

Mark Haacke1, Satish Krishnamurthy2, Jie Li2, Yimin Shen1

1Wayne State University, Detroit, USA 2Upstate Medical University, Syracuse, USA

Background: Hydrocephalus can be experimentally induced by producing a sustained increase in CSF osmolarity. This implies that the macromolecular content in CSF is critical in determining the ventricular volume. Therefore we hypothesized that macromolecular transport is altered in the presence of hydrocephalus. We have previously shown that macromolecules (dextran) are transported from the ventricles into the brain tissue and are rapidly concentrated in the perivascular space surrounding microvessels throughout the brain. This experiment was designed to determine if there is any difference in the kinetics of distribution of iron tagged dextran (Fe-Dextran) on MR imaging between normal rats and those with communicating hydrocephalus.

Methods: The rats were divided into two groups: normal and hydrocephalic. Communicating hydrocephalus was induced using the basal cistern kaolin injection prior to the study. Fe-Dextran was injected into the right lateral ventricle. In order to study the dynamic changes in iron content, a series of gradient echo sequences was run over a period two hours.

Results: High resolution SWI scans showed that there was a difference in the presence of Fe-Dextran in the lateral ventricle at one hour. Normal animals showed rapid clearance from the ventricles and the brain into the vascular system and eventually into the superior sagittal sinus. On the other hand, the hydrocephalic animals showed a very slow clearance from the ventricles and evidence of a build-up of Fe-Dextran in the brain tissue although this eventually also cleared in time. However, there was no evidence of Fe-Dextran clearance into the superior sagittal sinus in hydrocephalic animals.

Conclusions: Distribution kinetics of Fe-Dextran in the ventricle as well as in the brain parenchyma is clearly different in hydrocephalus compared to normal rats. This study confirms that intraventricularly injected Fe-Dextran is transported into the brain tissues prior to clearance into vascular system.

EXPERIMENTAL HYDROCEPHALUS

O-054: NEW HYPOTHESIS OF MECHANISM FOR CSF PRODUCTION AT THE CHOROID PLEXUS

Yasuhiko Hayashi, Daisuke Kita, Yu Shimizu, Masahiro Oishi, Seiichi Munesue, Yasuhiko Yamamoto, Yutaka Hayashi

Department of Neurosurgery, Kanazawa University, Kanazawa, Japan

Background: It is widely believed that cerebrospinal fluid (CSF) is actively excreted from choroid plexus (CP). This concept is based on the fact that aquaporin-1, selective water channel, abundantly exist on the ependymal cell on the CP. One of the Authors (Y.H.) reported the functions of AQP-1 on glioma cells, demonstrating the AQP-1 expression is dependent on activation of glycolysis (Neoplasia, 2007). Based on the result, a new hypothesis of CSF production at the CP is presented.

Methods: Following findings were obtained from the results of immunohistochemistry of surgical specimen of CP, which is rich in vessels without blood-brain barrier properties.

Results: 1. Localization of the AQP-1 on the ependymal cells is dominant on apical membrane, and also abundantly expressed in cytoplasm. 2. Lactodehydrogenase, an enzyme catalyzing a reaction pyruvate into lactate, is abundantly expressed on the ependymal cells. This reaction leads to development of lactoacidosis, production of lactate and H+. 3. This H+ excessive production is neutralized by bicarbonate buffer system, H+ + HCO3- → H2O + CO2. This reaction is catalyzed by carbonic anhydrase (CA) II, facilitates H2O production (development of cytotoxic edema). 4. Ependymal cell express AQP-1 to relax the cytotoxic edema. The apical side-dominant AQP-1 expression facilitates the H2O excretion into ventricle. 5. Abundant expression of glucose transporter type I on the ependymal cells mean the active intake of glucose to lead to massive glycolysis activation. 6. CA IX is strongly expressed on the endothelium of CP vessels, which means the acidification of the vessel’s surroundings. Cathepsin B was expressed on the endothelium, which activate angiogenesis under acidic microenvironment. This can enable to active glucose supply to the ependymal cell.

Conclusion: This new hypothesis of H2O production at the CP ependymal cells enables to explain the massive CSF production under the active glycolysis and angiogensis.

74 EXPERIMENTAL HYDROCEPHALUS

O-055: DOES PHYSIOLOGICAL INTRACRANIAL PRESSURE IN UPRIGHT POSITION HAVE POSITIVE OR NEGATIVE (SUBATMOSPHERIC) VALUE?

Marijan Klarica1, Milan Radoš1, Ivana Jurjevi1, Antonio Petoši1, Darko Oreškovi2

1University of Zagreb, School of Medicine, Department of Pharmacology and Croatian Institute for Brain Research, Zagreb, Croatia 2Ruer Boškovi Institute, Department of Molecular Biology, Zagreb, Croatia

Background: It is still not known which factors determine cerebrospinal fluid (CSF) pressure inside craniospinal space during changes of body position. According to our new hypothesis, the CSF pressure primarily depends on the laws of fluid mechanics and on the biophysical characteristics of the cranial and spinal CSF space.

Methods: We developed a new in vitro model of craniospinal CSF space which imitates anatomical dimensions and basic biophysical features of the craniospinal CSF space in cats. Volume and pressure changes in the newly developed CSF model are compared to those obtained on cats in horizontal and upright positions. Furthermore, measurement on cats were performed before and after blockade of craniospinal communication.

Results: In horizontal position, intracranial CSF pressure in cats was positive, but after verticalization a long- lasting appearance of negative CSF pressure inside the cranium was recorded. Results from our in vitro model do not differ significantly from CSF pressure values measured in upright and horizontal position on cats. After blockade of craniospinal CSF communication, cranial CSF pressure in verticalized cats was positive.

Conclusions: It seems that negative (subatmospheric) CSF pressure inside the cranium in an upright position is not a transitory observed appearance, but a physiological state of the CSF pressure (1).This findings implicate that cerebral perfusion pressure (CPP) is significantly higher in the upright position than it was previously supposed. Blockade of craniospinal communication leads to an increase of intracranial pressure in an upright position, and therefore, to a CPP decrease. Our newly developed CSF model faithfully imitates results obtained on cats, which emphasizes the importance of physical laws of fluid mechanics for understanding of CSF pressure. Finally, hydrostatic pressure gradients inside craniospinal CSF space are in conflict with classical concept of unidirectional CSF circulation.

EXPERIMENTAL HYDROCEPHALUS

O-056: CEREBROSPINAL FLUID MOVEMENT USING MAGNETIC RESONANCE IMAGING WITH TIME SPIN LABELING INVERSION PULSE METHOD IN CANINE HYDROCEPHALUS

Chieko Ishikawa1, Masato Kitagawa1, Daisuke Ito1, H Yamada1, Aya Sakurai2, Saeri Matsumoto2, Shinya Yamada2

1Nihon University College of Bio-resource Science, Kanagawa, Japan 2Toshiba Medical Systems, Tochigi, Japan

Introduction: Undisturbed CSF Cerebrospinal fluid dynamics (CSF) was studied non-invasively in canine physiological and pathophysiological brain using a magnetic resonance imaging (MRI) technique with Time-Inversion labeling Pulse method (Time-SLIP).

Methods: Fourteen normal, four hydrocephalus and four syringomyelia dogs were used in this study. All studies except one case were conducted under general anesthetized using isoflurane inhalation with i.v. propofol administration (remaining case was sedated using diazepam). Respiration was kept using a mechanical ventilator. Non-CSF related disease was used as normal control (mainly idiopathic convulsion dog). Only spontaneously developed hydrocephalus and syringomyelia dogs were used as pathophysiological brains. Observation time of CSF dynamics was 1-3 sec with 0.05sec increment using 1.5 T MRI with FSE Time-SLIP method. CSF motion patterns at the aqueduct, the pre-pontine cisterns and cranio-cervical junction were observed.

Results: Well pulsatile CSF motions were observed in the prepontine and the aqueduct in normal brain. The CSF motions were altered in the prepontine cistern and the aqueduct in some of hydrocephalic brains. The CSF flowing into the syrinx from forth ventricle may be detected by Time-SLIP method in canine syringomyelia.

Conclusion: The CSF motion patterns were observed by using a non-invasive MRI spin labeling technique in normal, hydrocephalus and syringomyelia anesthetized dogs.

75 CSF DYNAMICS

O-057: PRESSURE FORCE ON THE LATERAL VENTRICLE IS USEFUL TO PREDICT SHUNT RESPONSE FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS.

Hisayuki Murai, Masayoshi Kobayashi, Shigeki Nakano, Naokatsu Saeki

Department of Neurosurgery, Chiba University Graduate School of Medicine, Chiba, Japan

Background: Recently, cerebrospinal fluid (CSF) outflow resistance (Ro) is seemed to be less effective in predicting shunt response. However, shunt is a procedure to lower Ro, so measuring Ro should be important to understand the pathophysiology of hydrocephalus. CSF is seemed to be absorbed in many systems such as venous system and lymphatic system, and at many sites. Measuring Ro at the lumbar site only might be not enough. Measuring ventricular Ro might be useful but highly invasive. So we studied pressure force on the lateral ventricle (ventricle force) and its predictive value on shunt response.

Methods: Queckenstedt test positive cases and congenital or developmental NPH such as Blake’s pouch cyst were excluded. We studied 80 consecutive patients whose Ro were studied and shunted from April 2002 to July 2012 and followed more than one year in our hospital. Ro was measured by lumbar bolus injection method. Ventricle force was calculated as a product of the lateral ventricle surface area and an initial pressure measured at the lumbar puncture. The ventricle surface area was measured with T1-weighted coronal images with Image J software (NIH). Clinical condition of the patient was used iNPH grading scale.

Results: All patients with ventricle force over than 1.6 kg responded to shunt. With a cut-off value of 8 mmHg/ml/min for Ro, sensitivity and specificity are 57.3% and 80%, respectively. With a cut-off value of 1.6 kg for ventricle force, sensitivity and specificity are 78.7% and 100%, respectively. With a cut-off value of 8 for Ro or 1.6 for ventricle force, sensitivity and specificity are 93.3% and 80%, respectively.

Conclusions: In addition to the spinal Ro value and tap test, the pressure force on the lateral ventricle (ventricle force) is seemed to be useful in predicting shunt outcome and understanding pathophysiology of hydrocephalus.

CSF DYNAMICS

O-058: REDUCING OR INCREASING ICP PULSATION: EFFECT ON PARENCHYMAL BLOOD FLOW PULSATION

Sara Qvarlander1, Mark Luciano1, Stephen Dombrowski1, Francis Loth2, Serge El-Khoury1, Jun Yang1

1Cleveland Clinic, Cleveland, USA 2University of Akron, Akron, USA

Background: In the rigid cranium cardiac-induced intracranial pressure (ICP) and blood flow pulsatility are linked and have been suggested to have important physiological consequences, such as ventricular enlargement and capillary damage. We have developed a cardiac-gated oscillating bladder, here used in the epidural space to alternately accentuate or attenuate the normal ICP pulse through its volume action on the adjacent CSF space. This method was used to investigate the effect of specific ICP pulse alterations on pulsatile blood flow in the brain parenchyma.

Methods: An inflatable bladder was inserted into the lateral epidural space of 12 dogs. Volume oscillation was synchronized with the ECG and was either “synergistic”, deflating with cardiac systole, or “antagonistic”, inflating with systole, with variable volume change (max 1000 µl). As a result the ICP pulse could be reduced (R), inverted (I) or augmented (A). Tissue blood flow was measured in each hemisphere using local laser doppler probes, enabling analysis of the changes in cardiac- induced pulsatile parenchymal flow resulting from repeated random sequences (system off 2’/on 2’) of the protocols.

Results: The synergistic protocols (R, I) were associated with decreased initial ICP peak during cardiac systole, and increased mean and pulse amplitude of blood flow (p<0.05), with ICP inversion more effective than reduction (p<0.05). The antagonistic protocol (A), associated with increased ICP peak during systole, had no significant effect on blood flow, though its volume of bladder oscillation was equivalent to, or greater than the other protocols (I, R respectively).

Conclusions: These results suggest that timing and amplitude of the ICP pulse can be manipulated independently, and that these factors have different effects on pulsatile flow dynamics. In contrast to the pulse augmentation, when ICP pulsatility was reduced or inverted an increase in parenchymal flow pulsatility was observed, suggesting that the intracranial Windkessel mechanism was modulated.

76 CSF DYNAMICS

O-059: DIRECT EVIDENCE OF VASCULAR COMPRESSION AND CEREBRAL CIRCULATORY DISTURBANCE IN NPH PATIENTS

Tomohisa Omura, Yoshinaga Kajimoto, Hiroji Miyake, Toshihiko Kuroiwa

Department of Neurosurgery, Osaka Medical College, Osaka, Japan

Background: Several studies using MRI flowometry suggested decrease of intracranial or vascular compliance may be an evidence of compression intracranial venous vessel, consequently may cause the circulatory disturbance in NPH patients. It is an attractive hypothesis, however, no study showed those relations directly. To prove this hypothesis, we measured the change of cerebral blood volume (CBV) while performing intra-ventricular intermittent infusion of CSF in NPH patients; we clarified relationship among intra-cranial pressure (ICP), intracranial compliance, CBV, and cerebral oxygenation state.

Methods: For 22 NPH patients (12 idiopathic NPH, 10 secondary NPH) who performed VP shunt, we pulled CSF out from Ommaya reservoir at burr hole and re-infused 3ml of CSF intermittently into the ventricle under continuous monitoring of ICP, and calculated intracranial compliance. At the same time, we put a single channel of near infra-red spectroscopy probe on the forehead and observed the change of total-Hb oxy-Hb, and deoxy-Hb in the frontal lobe outer layer region. We also measured ICP in on- and off-state of shunt by switching incorporated on-off valve.

Results: Total-Hb, which is the index of CBV, decreased with increase of ICP. At shunt off state, as ICP elevated to 15.06±6.31mmHg, intra-cranial compliance decreased to 0.69±0.25 ml/mmHg, decreased CBV and slight increase of deoxy-Hb also observed. At shunt on state, ICP decreased to 5.31±3.95mmHg and compliance increased to 3.36±1.32 ml/mmHg, and CBV increased.

Conclusions: We proved that the change of intracranial compliance linked the decrease of CBV by compression of intracranial vascular (mainly vein) in NPH. In addition, the increase of deoxy-Hb suggested cerebral circulatory disturbance.

CSF DYNAMICS

O-060: AGREEMENT OF PRESSURE AND WAVE AMPLITUDE RETRIEVED FROM THE LUMBAR SUBARACHNOID SPACE AND FROM THE BRAIN PARENCHYMA

Emilio González-Martínez1, David Santamarta2

1University Hospital of Álava, Vitoria, Spain 2University Hospital of León, León, Spain

Background: Intracranial pressure (ICP) monitoring and lumbar infusion test contribute to the management of hydrocephalus. Although it may be obvious to present a high agreement between mean basal pressure and wave amplitude from both tests, no study has determined it. Our goal has been to analyse the agreement of mean pressure and wave amplitude retrieved from the lumbar subarachnoid space during the basal stage of the lumbar infusion test and from the brain parenchyma during overnight monitoring.

Methods: Retrospective analysis of 85 patients with various forms of hydrocephalus who underwent ICP monitoring during two consecutive nights followed by a lumbar infusion test. The pressure transducer was placed into the brain parenchyma during ICP monitoring and into an extension line fluid-coupled to the lumbar subarachnoid space during the infusion test. Mean pressure and wave amplitude during the basal stage of the infusion test were measured. ICP monitoring was performed overnight and the same parameters were calculated from 8-hour (11 pm to 7 am) recordings.

Results: The mean basal pressure was higher in the infusion test (8.1 vs. 7.5 mmHg, p=0.063). However, the mean wave amplitude was higher in overnight ICP recordings (5.0 vs. 2.8 mmHg, p=0.004). Mean pressure and wave amplitude during the two consecutive nights showed high concordance (Pearson’s correlation 0.737- p=<0.001- and 0.900 -p<0.001-, respectively). Pressure and wave amplitude from ICP monitoring and infusion test presented low consistency (Intraclass Correlation Coefficient 0.202 and 0.278, respectively). Bland-Altman plots suggested the higher the pressure and wave amplitude, the higher the difference.

Conclusions: The mean pressure and wave amplitude during ICP overnight monitoring present high agreement between consecutive nights. However, there is a low consistency and agreement between these parameters retrieved from the lumbar subarachnoid space during the basal stage of the infusion test and from the brain parenchyma during overnight monitoring.

77 CSF DYNAMICS

O-061: CSF DYNAMIC SLOW VASOGENIC WAVES ARE SUPPRESSED BY GENERAL ANAESTHESIA

Zofia Czosnyka, Marek Czosnyka, Joseph Donnelly, Piotr Smielewski, Matthew Garnett, John Pickard

Academic Neurosurgery, Cambridge Biomedical Campus, UK

Background: Elevation of ICP during infusion study in NPH is usually followed by an increase of activity of slow (20 sec to 2 min period) vasogenic waves. The waves are supposed to be provoked by fluctuation of cerebral blood volume. They can be seen in conscious patients, as described by many Authors before. However, in rare cases when the study is performed under general anesthesia, such a phenomenon is not observed.

Methods: We compared infusion studies in two age-matched groups of 20 patients each, diagnosed for hydrocephalus using constant rate infusion method. One group was investigated through Hydrocephalus Clinic, Addenbrookes Hospital, Cambridge UK, as day cases- they were fully conscious. Second group were admitted to hospital and infusion study was performed under general anesthesia. Magnitude of slow waves was assessed using spectral analysis and effective amplitude of waves in a bandwidth 0.05 to 0.008 Hz was calculated.

Results: Baseline pressures, resistance to CSF outflow and elasticity were similar in two groups (p>0.05). Slow vasogenic waves were lower in GA group (p< 0.05) at a baseline. Magnitude in slow waves was increasing with elevation on mean ICP in conscious patients (R=0.74; p<0.05) but not in patients under GA (R=0.13, p=0.31). During plateau phase of infusion study magnitude in patients under GA was remarkably lower than in conscious patients (p<0.0001). In both groups pulse amplitude of ICP showed good association with mean ICP level. Although rare in patients suffering from NPH, plateu waves of ICP, can be noticed in both groups (anecdotal, 1 case in each group).

Conclusion: Dynamics of ICP seems to be suppressed by general anesthesia. Elements of clinical assessment of NPH, based on slow waves may be not valid in patients examined under GA.

CSF DYNAMICS

O-062: AN HYDRAULIC MODEL OF INTRACRANIAL SYSTEM: ROLE OF THE BRIDGING VEINS IN THE AUTOREGULATORY MECHANISMS

Carmelo Anile1, Antonio Ficola2, Pietro Santini1, Marek Czosnyka3

1Institute of Neurosurgery, Catholic University, Rome, Italy 2Department of Engineering, University of Perugia, Perugia, Italy 3Department of Clinical Neurosciences, University of Cambridge, UK

Background: Hydraulic model of intracranial system was built for investigating the purely physical mechanisms leading to ventricular dilatation. To evaluate the reliability of this model in reproducing the behaviour of an human intracranial system, an analysis of hydrodynamic parameters was carried out. In this study we report the preliminary results utilizing the infusion test methodology.

Methods: The hydraulic model was constructed as a water filled glass cylinder containing two spiral elastic tubes of different length and calibre, mimicking arterial and venous beds, interconnected by a device simulating the capillary bed. The venous outlet to the atmosphere is modelled by either collapsible or rigid tubes, reproducing, in the first case, the Starling’ resistor function. Pulsatile flow (F) into the tubes is produced by an external pump, while two micrometer valves cause the fluid circulation simulating cerebrospinal fluid production and absorption. Inlet mean pressure (IP) and flow together with intra- cylinder pressure (ICP) were recorded. Two different infusion rates have been applied, at 1 ml/min, in order to reproduce the classical infusion test, and at 5 ml/min in order to simulate a condition of intracranial hypertension. The tests were performed in two conditions, with collapsible or with rigid tubes at venous outlet. Linear regression between ICP mean value and the corresponding first harmonic amplitude (AMP) and the curve correlating F and the difference (IP-ICP) were considered as comparison with the human intracranial system.

Results: With rigid tubes, no effect on the ICP/AMP relationship and on F were observed; conversely, with collapsible tubes, at 1 ml/min infusion rate a positive linear regression of ICP/AMP with a slope of 0.27 was observed. At 5 ml/min, rate F decreased when the (IP-ICP) decreased below 55 mmHg.

Conclusions: The model appears to be able to simulate some aspects of the hydrodynamic behaviour of an human intracranial system.

78 CSF DYNAMICS

O-063: DOES AQUEDUCTAL STENOSIS INFLUENCE INFUSION TEST IN NORMAL PRESSURE HYDROCEFAPHALUS?

Emilio González-Martínez1, David Santamarta2

1University Hospital of Álava, Vitoria, Spain 2University Hospital of León, León, Spain

Background: Late-onset idiopathic aqueductal stenosis may present with clinical features indistinct from idiopathic normal pressure hydrocephalus (iNPH). Moreover, aqueductal stenosis (AS) may be easily overlooked by conventional magnetic resonance imaging (MRI). The goal of this study has been to analyse whether the patency of the aqueduct involves different results in infusion tests performed in patients with normal pressure hydrocephalus (NPH) syndrome.

Methods: Retrospective analysis of 79 patients consecutively admitted for NPH syndrome (slowly progressive impairment of gait and balance, cognitive deterioration and sphincter dysfunction accompanied by ventricular widening) who underwent a lumbar infusion test between 2006 and 2013. Patients with precipitating factors of hydrocephalus were excluded. The patency of the aqueduct was determined with high resolution sagittal constructive interference in steady state MRI. The following infusion test parameters were measured and compared between patients with iNPH and late-onset AS: the resistance to CSF outflow (Rout), the median values of pressure and wave amplitude during baseline, the early infusion and the plateau stages.

Results: Fifty patients were included in this study. Nine patients had AS (18%). Gender, age and ventricular size were similar in both groups. Patients with AS had slightly lower values of Rout than iNPH patients (11.1 vs. 12.7 mmHg/ml/min, respectively -p>0.05). Pressure values and wave amplitude during the three stages analysed were similar in both groups. No statistically significant difference was detected (p>0.05).

Conclusions: Patients with NPH symptoms and ventriculomegaly have not shown differences of infusion test parameters regardless of the patency of the aqueduct.

CSF DYNAMICS

O-064: UNDERSTANDING THE PHYSICS OF OVERDRAINAGE

Christoph Miethke

Christoph Miethke GmbH&Co.KG, Germany

Background: Since the introduction of shunts for the treatment of hydrocephalus the complication of overdrainage has been questioned as the primary hydraulic problem. Although the underlying physics is well described there is still a discussion about whether or not overdrainage is just a posture depending phenomenon.

Methods: To discuss the principle physical phenomena of overdrainage a odel has been developed which stepwise more sophisticatedly addresses the situation of the ventricles within the brain: an open container, a container covered with a membrane, a container covered with a membrane and a hard plate (modelling the bone), the same model including a vessel and an included distal catheter modelling the hydrostatic pressure within an integrated shunt. The vessel is connected to a fluid-compartment, which is modelling the venous blood pressure. The model allows the pressure increase within the blood vessels and a changing hydrostatic pressure within the shunt. The investigation of the behaviour of the modelled subarachnoidal space after changing the parameters within the venous blood and the shunt describes the possible phenomena of overdrainage.

Results: The model clearly explains a possible principle of overdrainage followed by the changing hydrostatic pressure. Overdrainage as a consequence of increased blood pressure cannot be explained or understood by the model.

Conclusions: Regardless whether or not overdrainage can occur in crying prematures while they are lying, the physics of posture depending overdrainage can clearly be described and understood by the proposed model. Logically based on theses in-vitro-investigations valves for VP-shunting should systematically address posture depending changes within the shunt-system to overcome overdrainage related complications.

Conclusions: The shift of the AB42 from oligomer to monomer and a change in gamma-secretase activity may be a result of improved cerebrospinal turnover due to shunting. Our findings suggest that the shunting procedure can delay intracerebral deposition of AB in patients with iNPH.

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O-065: LONG-TERM OUTCOME OF PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS (INPH) TREATED WITH LUMBOPERITONEAL SHUNT (LPS): A MULTICENTER PROSPECTIVE STUDY (SINPHONI-2)

Masakazu Miyajima4, Hiroaki Kazui1, Etsuro Mori2, Masatsune Ishikawa3,

1Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan 2Tohoku University, Sendai, Japan 3Normal Pressure Hydrocephalus Center, Otowa Hospital, Kyoto, Japan 4Department of Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan

Background: There is currently no established evidence for the use of LPS as a treatment for iNPH. We conducted a multicenter prospective study of LPS for patients with iNPH. This integrated a 3 month randomized controlled trial (RCT phase) comparing LPS with conservative therapy and a 1 year extension study, where all subjects received an LPS and were examined periodically during the 12 months following the procedure. Here, we report long-term outcome of the patients.

Methods: Twenty centers in Japan were involved in this study. Patients aged between 60 and 85 years with one or more symptoms (gait, cognitive, and urinary problem) and MRI evidence of ventriculomegaly and tight high-convexity and medial subarachnoid spaces received LPS immediately or 3 months after randomization in the RCT phase, and were followed-up over 1 year after LPS. The primary endpoint was a favorable outcome (improvement of ≥1 level on the modified Rankin Scale: mRS) at 1 year after surgery, and the secondary endpoints included improvement of ≥1 level on the total score of the iNPH grading scale. Shunt responder was defined as ≥1 level on mRS at any evaluation point in one year. Results: The full analysis set included 84 patients. A favorable outcome was achieved in 62%, and 70% were shunt responders. When measured with the iNPH grading scale, the 1-year improvement rate was 75%, and response to the surgery at any evaluation point was detected in 85%. Serious adverse events were recorded in 19 patients, ten of which were events related to surgery: 4 subdural hematoma requiring surgery, 4 distal catheter failure and 1 proximal catheter failure requiring surgical repair, and meningitis.

Conclusions: LPS with programmable valves were as equally effective and safe for the treatment of iNPH. LPS is considered as a practical alternative to VPS for iNPH.

CLINICAL TRIALS IN HYDROCEPHALUS

O-066: EFFECT OF LUMBOPERITONEAL SHUNT SURGERY FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A RANDOMIZED CONTROLLED TRIAL (SINPHONI-2)

Hiroaki Kazui1, Etsuro Mori2, Masatsune Ishikawa3, Masakazu Miyajima4

1Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan 2Tohoku University, Sendai, Japan 3Normal Pressure Hydrocephalus Center, Otowa Hospital, Kyoto, Japan 4Department of Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan

Background: Lumbo-peritoneal shunt (LP) surgery is less invasive to the brain but performed less frequently than ventriculo- peritoneal shunt surgery for idiopathic normal pressure hydrocephalus (iNPH). We conducted a multicenter prospective study of LP shunt for patients with iNPH (Study of Idiopathic Normal Pressure Hydrocephalus On Neurological Improvement - Efficacy and safety of LP shunt: SINPHONI-2), which integrated a 3-month randomized controlled trial comparing LP shunt with conservative therapy (RCT phase) and 1-yer extension study, where all subjects received LP shunt and examined over 1-year after LP shunt. Here, we report the results of the RCT phase of SINPHONI-2.

Methods: Twenty centers in Japan were involved in this study. iNPH patients with MRI features of ventriculomegaly and tight high-convexity/medial subarachnoid spaces were randomly allocated to either the Shunt group or Control group. The primary outcome was the modified Rankin scale (mRS), and secondary outcomes included the iNPH grading scale (iNPHGS), two walking tests, four cognitive tests, and caregiver burden scale. These evaluations were performed before and 3 months after each intervention, and the changes were compared between the two groups.

Results: Forty-six patients were assigned to the LP shunt arm and 42 to the control arm in this study. The ratios of patients who had improvement of one level or more on the mRS at 3 months after intervention were significantly higher in Shunt group (69.6%, 95%CI:54.0-81.2%) than in Control group (4.8%, 95%CI:0.59-16.5%). Shunt group had significantly better improvement in the mRS, iNPHGS scores, both of the two walking tests, and three of the four cognitive tests, and caregiver burden scale. Serious adverse events occurred in 13% of patients in the Shunt group, all of which were related to shunt placement.

Conclusions: LP shunt surgery is safe and effective in improving functional status and triad symptoms in iNPH patients.

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O-067: A DOUBLE-BLIND RANDOMIZED TRIAL ON THE CLINICAL EFFECT OF DIFFERENT SHUNT VALVE SETTINGS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Dan Farahmand1, Terje Sæhle2, Per Kristian Eide2, Magnus Tisell1, Per Hellström1, Carsten Wikkelsö1

1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Neurosurgery, Oslo University Hospital, Oslo, Norway

Background: To examine the effect of gradually reducing the opening pressure on symptoms and signs in the shunt treatment of idiopathic normal pressure hydrocephalus (iNPH).

Methods: In this prospective double-blinded, randomized, controlled, double-centre study on patients with iNPH, a VP shunt with an adjustable Codman Medos Valve was implanted in 68 patients randomized into two groups. In one group (20-4) the valve setting was initially set to 20 cm H2O and gradually reduced to 4 cm H2O over the course of the 6 month study period. In the other group (12), the valve was kept at a medium level of 12 cm H2O during the whole study period. All patients were clinically evaluated using four tests preoperatively as well as postoperatively at 1, 2, 3, 4 and 6 months. The test scores between the two groups (20-4 and 12) were compared for each clinical evaluation.

Results: Fifty-five patients (81 %) were able to complete the study. There were no significant differences between the two groups (20-4 and 12) preoperatively or at any time postoperatively. Both groups exhibited significant clinical improvement after shunt insertion at all valve settings compared to the preoperative score, with the greatest improvement observed at the first postoperative evaluation. The clinical improvement was significant within the first three months and thereafter no significant improvement was seen in either group.

Conclusions: Gradual reduction of the valve setting from 20 to 4 cm H2O did not improve outcome compared to a fixed valve setting of 12 cm H2O. Improvement after shunt surgery in iNPH patients was evident within three months, irrespective of valve setting.

CLINICAL TRIALS IN HYDROCEPHALUS

O-068: A RANDOMIZED CONTROLLED DOUBLE-CENTRE TRIAL ON SHUNT COMPLICATIONS IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS TREATED WITH GRADUALLY REDUCED OR “FIXED” PRESSURE VALVE SETTINGS

Dan Farahmand1, Terje Sæhle2, Per Kristian Eide2, Magnus Tisell1, Per Hellström1, Carsten Wikkelsö1

1Hydrocephalus Research Unit, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Sweden 2Department of Neurosurgery, Oslo University Hospital, Oslo, Norway

Background: To investigate whether a gradual reduction of the valve setting level (opening pressure) decreases the complication rate in idiopathic normal pressure hydrocephalus (iNPH) patients treated with a ventriculo-peritoneal (VP) shunt.

Methods: In this prospective double-blinded, randomized, controlled, double-centre study on patients with iNPH, a VP shunt with an adjustable Codman Medos Valve was implanted in 68 patients randomized into two groups. In one group (20-4) the valve setting was initially set to 20 cm H2O and gradually reduced to 4 cm H2O over the course of the 6 month study period. In the other group (12), the valve was kept at a medium level of 12 cm H2O during the whole study period. The time to and type of complications (hematoma, infection and mechanical problems) as well as overdrainage symptoms were recorded. Symptoms, signs and outcome were assessed by the iNPH scale and the NPH grading scale.

Results: Six patients in the 20-4 group (22 %) and seven patients in the 12 group (23 %) experienced a shunt complication; nine had subdural hematomas, three mechanical obstructions, and one infection with no difference between groups. The frequency of overdrainage symptoms was significantly higher for a valve setting of ≤ 12 cm H2O compared to a setting of > 12 cm H2O. The 20-4 group had a higher improvement rate (88 %) than the 12 group (62 %) (p=0,032). Neither BMI, the use of an anti-siphon device or anticoagulants were related to complications.

Conclusions: Gradual lowering of the valve setting to a mean of 7 cm H2O led to the same rate of shunt complications and overdrainage symptoms as a fixed valve setting at a mean of 13 cm H2O but had a significantly better outcome.

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O-069: MILESTONES OF PROGRESS AND SETBACKS IN THE TREATMENT OF HYDROCEPHALUS - A LEARNING CURVE OF 40 YEARS

Christian Sprung

Neurosurgical Clinic, Charité, Universitätsmedizin Berlin, Germany

Background: More than 60 years ago the introduction of shunts with reliable valves revolutionized the therapy of hydrocephalus. After first enthusiasm, a nightmare of complications increasingly dampened the optimism and ruined the results gained with these devices. But during the last decades, significant technical improvements lead to a decrease of complications and revisions as well as to an increase of shunt survival. On the other hand, some setbacks hindered a continuous advancement and several problems remained unsolved up to now. These contradicting developments will be illustrated, also by the learning curve of the Author.

Methods: The advancements achieved over the years can be differentiated in those of “hardware” like improvements of valves, anti-syphon units, reservoirs and catheters or devices for in-vivo pressure-measurement on the one side, and in “software” improvements with increase of understanding regarding pathophysiology, optimal pressure levels and avoidance of surgical and mechanical complications on the other. We will try to quantify the increase of knowledge in the most important of these parameters and point out the long list of problems not solved until now.

Results: Whereas operative advancements over the years were marginal and the increase of insights concerning pathophysiology of NPH and rational of its shunt-therapy remains limited, the avoidance of severe complications by adjustable hydrostatic valves and further improvement of other parts of the shunt is evident. The progress, but also the avoidable errors and setbacks in the development will be illustrated by personal experience over the last 40 years and by evidenced scientific results.

Conclusion: Despite justified criticism against the biomedical industry significant improvements of hardware are evident and better insight into pathophysiology of hydrocephalus lead to a significant better outcome in shunting of hydrocephalus. But further efforts are essential necessitating cooperation between neurosurgeons on the one hand and biomedical engineers on the other.

PEDIATRIC HYDROCEPHALUS II

O-070: FETAL VENTRICULOMEGALY: WHAT DOES IT MEAN? Patricia Barrio1, Bienvenido Puerto2, Javier Pérez1, David Santamarta1

1Department of Neurosurgery. University Hospital of León (Spain) 2Department of Maternal – Fetal Medicine. ICGON, Clínic Hospital. University of Barcelona, IDIBAPS Barcelona (Spain)

Background: Ventriculomegaly (VM) is the most common anomaly of the Central Nervous System detected in fetal life. It is defined as a lateral ventricular diameter measuring greater than 10 mm at the level of the atria on an axial plane at any point during gestation, as measured by sonography or magnetic resonance imaging (10 – 15 mm, mild or moderate VM; > 15 mm, severe VM). The prevalence of VM varies between 0.3 and 1.5 per 1,000 births, depending on the technique used for measuring, the evaluation of one or both lateral ventricles and gestational age at examination.

Methods: The relevant literature was reviewed giving particular interest in outcomes.

Results: Up to 50% of cases are associated with other abnormalities (structural defects 33–61%, chromosomal aberrations 3–9% and congenital infection 5%). Additional neonatal imaging is needed to be performed because prenatal imaging showed a false negative rate of 7.4%. In confirmed mild isolated ventriculomegaly is related to a prevalence of neurodevelopmental delay of 7.9%.

Conclusions: In spite of advancements in prenatal imaging and molecular diagnosis of fetus, the management of fetal ventriculomegaly is still limited. The detection of associated abnormalities is essential for proper prognosis assessment. Isolated mild VM in the prenatal period constitutes an easy-to-detect diagnosis but a difficult-to-assess condition. However, parents and pediatricians should be advised that it delays in different areas of neurological development may appear during the infant period.

82 PEDIATRIC HYDROCEPHALUS II

O-071: ONE YEAR FAILURE RATES FOR DE-NOVO VENTRICULO-PERITONEAL SHUNTS IN UNDER 3-MONTH-OLD CHILDREN

Gulam Zilani, Anthony Amato-Watkins, Jozef Lang, Imran Bhatti, Paul Leach

Department of Paediatric Neurosurgery, University Hospital of Wales, Cardiff, United Kingdom

Background: Ventriculo-peritoneal shunts (VPS) are still the mainstay treatment for hydrocephalus in children. It is generally accepted that VPS failure and infection rates are higher for neonates than for older children. Our study aimed to compare our one year failure and infection rates in under 3-month-olds compared with children of all ages in our department.

Methods: Our published one year shunt failure rate at our institution is 28.6% for all children under 16 years old and our infection rate is 4.3% (1). We identified 39 neonates under 3 months of age who underwent VPS insertion between January 2007 and December 2012 and assessed their shunt failure and infection rates for comparison.

Results: The neonates had a 25.6% (10) shunt failure rate for any reason over the first year. There was one infection (2.6%) and 9 (23.1%) failed due to shunt blockage. All cases were due to blockage of the ventricular catheter except for one which was a valve obstruction from a blood clot within the valve mechanism. Our two studies therefore show similar outcomes for all children compared to neonates alone.

Conclusion: Children under 3-months-old undergoing VPS insertion should not automatically expect an increased 1 year failure or infection rate compared with older children. The reasons for this maybe as a result of increased subspecialisation, the more widespread use of anti-biotic impregnated catheters and improved neonatal care.

PEDIATRIC HYDROCEPHALUS II

O-072: THE EXPLORATION OF HOW AND WHY SHUNTS OBSTRUCT Pat McAllister1, Carolyn Harris1, Kelsie Pearson1, Kristen Trett1, Badri Roysam2, Samuel Browd1, Bill Shain1.

1Seattle Children’s Hospital, Seattle, WA, USA 2University of Houston, Houston, TX, USA

Background: Approximately 80% of patients with hydrocephalus suffer long-term neurological deficits. Symptoms of hydrocephalus are treated by using a shunt to permit CSF drainage. After ten years of implantation, 85% of these devices will fail, causing neurological deficits to worsen. Shunt failure commonly occurs from tissue obstruction. Cells and tissues obstructing shunts were qualitatively identified in 1982 predominately as connective, chronic inflammatory, granulomatous, glia, and choroid plexus, but the organization and makeup of these cellular tissue masses has not been well quantified to date.

Methods: Using an imaging toolkit and rendering, we can: identify and count each cell type, attain detailed characteristics of cell morphology, and accurately identify the three-dimensional relationships between cells and catheter features. We will use these data to understand: cell responses as a function of distance from the catheter surface and distance from each catheter hole, cell organization, and the role of vascularization. Samples recovered from the operating room include obstructed and unobstructed catheters. We will use these data to test our hypothesis that shunt obstruction is, in part, a multi-stage process that begins with initial attachment of inflammatory astrocytes and microglia, which results in whole or partial obstruction simultaneous to recruitment of other cells and tissues, including choroid plexus.

Results: Present results indicate that tissue occluding shunts has a high cell density compared to control cortical tissue, is vascularized, and contain an interlocked grid of astrocytes and microglia. The morphology of tissue obstructing shunts appears to be highly patient dependent.

Conclusions: It appears that astrocytes are, very generally, localized in and around the shunt holes, whereas the choroid plexus attaches to accumulated astrocytes and microglia obstructing or beginning to obstruct holes. We anticipate using this new information to understand the mechanisms that cause tissue obstruction and to develop new strategies for improving shunt performance.

83 PEDIATRIC HYDROCEPHALUS II

ABSTRACT NUMBER: 073

CSF DYNAMICS IN PEDIATRIC PATIENTS PRESENTING AN INTRACRANIAL CSF VOLUME INCREASE

Florine Dallery, Cyrille Capel, Bader Chaarani, Roger Bouzerar, Catherine Gondry-Jouet, Olivier Balédent

University Hospital, Amiens, France

Background: The CSF volume increase in the cranium is frequently observed in the ventricles or in the subarachnoid spaces of newborn and children patients. In cases number, morphological images can’t conclude if it is a passive or active dilatation. Recently, Phase contrast MRI (PC-MRI) has shown that CSF oscillations increase with growth while keeping a similar ratio between the CSF oscillations in the aqueduct and in the spinal canal. The aim of this work was to check whether the CSF hydrodynamics can bring complementary information to study pediatric population when a CSF volume increase occurs.

Methods: 44 patients (newborns and children; mean age=31±32 months; 5 days – 110 months) with an intracranial CSF volume increase (ventricular and/or subarachnoid spaces) underwent a morphological MRI and a PC-MRI study to quantify CSF oscillations. A CSF dynamics index (CSFdyn) was calculated, equal to the CSF stroke volume at the cervical level in the spine divided by the stroke volume in the aqueduct. A CSF volume index (CSFvol) was calculated, equal to the intracranial subarachnoid spaces area divided by the ventricular area. These areas were normalized with the size of the cranium.

Results: 24 patients presented only a ventricular dilatation: (CSFdyn=0.20±0.25; CSFvol=118±148; with no correlation R2=0,007). 18 patients presented a dilatation in both ventricular and subarachnoid spaces: (CSFdyn=18±17; CSFvol=2±1; with a slight positive correlation R2=0,23; P=0.06) and 4 patients presented only a dilatation in the subarachnoid spaces : (CSFdyn=11±6 ; CSFvol=1±0.19).

Conclusions: In the pediatric population, the absence of correlation between the dynamics of the CSF and its volume shows that the CSF oscillations are not only the result of the size of the ventricles or the subarachnoid spaces. The CSF oscillations bring complementary information concerning the active aspect of the CSF and could help the neurosurgeon to select a potential neurosurgery.

NORMAL PRESSURE HYDROCEPHALUS

O-074: IMPACT OF CEREBROSPINAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS ON THE AMYLOID CASCADE

Masao Moriya, Masakazu Miyajima, Madoka Nakajima, Ikuko Ogino, Hajime Arai.

Department of Neurosurgery, Kasai Shoikai Hospital, Tokyo, Japan

Background: The aim of this study was to determining the effect of cerebrospinal fluid(CSF) shunting on the amyloid cascade.

Methods: Here, we measured the levels of Alzheimer’s disease(AD)-related proteins in the CSF before and after lumboperitoneal shunting.

Results: Lumbar CSF of 32 patients with idiopathic normal pressure hydrocephalus(iNPH) (23 men and nine women, aged 73.7 ± 6.8 years [mean ± SD]; samples were obtained before and 1 year after shunting), 15 patients with AD (11 men and four women, aged 71.5 ± 10.6 years), and 12 normal controls (3 men and nine women, aged 67.1 ± 11.0 years) were analyzed for soluble amyloid precursor proteins(sAPP), amyloid beta-peptide(AB), amyloid precursor protein-like protein(APL1), and tau and phosphorylated-tau protein. We found that before shunting, individuals with iNPH had significantly lower levels of both the sAPP we investigated as well as an AB38 compared to patients with AD and controls. Additionally, in patients with iNPH, levels of AB38, 40, and 42, tau, and phosphorylated-tau were significantly higher after shunting than before shunting. (p= <0.001~0.014) On the other hand, there was no significant change in the levels of APL1 25, 27, and 28 after shunting. We further divided the patients with iNPH into patients with favorable and those with unfavorable outcomes. Compared to the unfavorable outcome group, the favorable outcome group showed significant increases of Aβ38/40 and phosphorylated-tau levels after shunting. Finally, after lumboperitoneal shunt, we observed positive correlations with shifts from APL1 28 to 25 and from AB 42 to 38 in all iNPH patients.

Conclusions: The shift of the AB42 from oligomer to monomer and a change in gamma-secretase activity may be a result of improved cerebrospinal turnover due to shunting. Our findings suggest that the shunting procedure can delay intracerebral deposition of AB in patients with iNPH.

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O-075: CLINICAL OUTCOMES IN SHUNTING IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS WITH AND WITHOUT ALZHEIMER DISEASE NEUROPATHOLOGIC CHANGES

Daniele Rigamonti, Ignacio Jusue-Torres, Mira Patel, Sachin Batra, Kathryn Carson, Barbara Crain, Abhay Moghekar, Jamie Hoffberger

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

Background: Idiopathic Normal Pressure Hydrocephalus (iNPH) and Alzheimer disease (AD) have clinical similarities (elderly, progressive onset and dementia). Some iNPH studies claim that with comorbid AD, shunting does not improve clinical outcomes. We study preoperative differences in gait, cognition and urinary problems in iNPH patients with and without AD­ related pathology and compare outcomes among them.

Methods: Between 2009 & ­2013, 98 patients (median age=72 years) underwent preoperative clinical testing for iNPH and subsequent shunting. Cortical biopsies obtained during shunting were stained with a modified Bielschowsky silver stain and immunohistochemistry for amyloidbeta­ and phosphorylated tau. Sections were evaluated using 2012 NIAAA­ guidelines. Demographic data, pre ­and post lumbar­ puncture (LP) tap test results, and pre and postoperative­ Tinetti, Timed up-and-­ ­go (TUG), and Min iMental­ State Exam scores were collected. The times of onset for gait impairment and cognitive difficulties were compared.

Results: There were no significant differences between patients with and without neuritic plaques, with sparse vs. moderate plaques, or with and without tau protein regarding pre­ and post-­LP tap test results, pre ­and post­ shunting gait, or cognitive scores. Cognition impairment at presentation did not correlate with AD pathology. Patients >75 years old at the time of shunting (OR 4.62, 95% confidence interval (CI) = 1.78­11.95, p=0.002) and patients with smaller post-LP­ TUG changes (OR 0.94, 95%CI=0.88 ­0.99, p=0.02) were more likely to have neuritic plaques. Older patients (OR 0.15, 95%CI=0.050.27,­ p=0.005), higher pre-LP­ TUG (OR 0.04, 95%CI=0.0090.08,­ p=0.01) and smaller post-LP­ TUG changes (OR 0.08, 95%CI=0.0090.16,­ p=0.02) were more likely to have positive tau protein.

Conclusions: Our study did not reveal preoperative differences in onset patterns or postoperative clinical outcomes between iNPH patients with and without AD pathology. This may be the result of rigorous patient selection for shunting. The clinical possibility of mild or moderate AD should not preclude shunting for iNPH when tap test is positive.

NORMAL PRESSURE HYDROCEPHALUS

O-076: DEPRESSION IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Hanna Israelsson1, Anders Eklund2, Jan Malm3

1Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden, 2Department of Radiation Sciences, Umeå University, Umeå, Sweden 3Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden

Background: Depression is a common disease that affects overall morbidity and mortality amongst elderly and is known to be over-represented in dementias. However, the prevalence of depression in patients with idiopathic normal pressure hydrocephalus (INPH) is inadequately known. The objective of this case-control study, part of the INPH-CRASH study, was to assess the prevalence of depression pre- and post- surgery in INPH-patients, compared to an age- and sex-matched community-based population.

Methods: All INPH-patients who were shunted in 5 out of 6 Swedish neurosurgical centres 2008-2010 were scrutinized. Individuals remaining after exclusion criteria (inability to communicate, pre-operatively mini mental state estimation <23, age <60 and >85) visited their nearest health-care giver and answered a questionnaire. Matched controls were assessed from the Swedish population index and underwent the same procedure. Depression was screened for using the Geriatric Depression Scale-20 (GDS-20), higher score meaning a higher probability for depression, with a cut-off value of 5 points for suspicion of depression.

Results: 544 individuals participated, 177 INPH-patients (42% females) and 367 controls (37% females). Patients had more depressive symptoms before than after surgery (7.4 points ±4SD versus 6.2 points ±5SD, p<0.005). Controls differed significantly from patients both before and after surgery (3.0 points, ±3SD, p<0.001). When using the cut-off value, 61% of the patients had suspected depression before and 50% after surgery (p<0.05). Amongst the controls, 18% had suspected depression. Patients were more likely to have a suspected depression both before (OR 7.3, 95%CI 4.8-11.2) and after (OR 4.5, 95%CI 3.0-4.9) surgery than controls (p<0.001).

Conclusions: Depression is common in patients with INPH. After surgery, the prevalence of depression declines, but still is almost three times higher than in the normal population. Screening for depression is probably indicated in INPH, and adequate treatment should start if needed.

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O-077: QUALITY OF LIFE IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS Hanna Israelsson1, Anders Eklund2, Jan Malm3

1Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden, 2Department of Radiation Sciences, Umeå University, Umeå, Sweden 3Department of Pharmacology and Clinical Neuroscience, Umeå University Hospital, Umeå, Sweden

Background: The impact of surgery regarding quality of life (QoL) in patients with idiopathic normal pressure hydrocephalus (INPH) is essential. The primary objective of this case-control study, part of the INPH-CRASH study, was to compare QoL before and after surgery in INPH-patients, compared to an age- and sex-matched community-based population. We will also report more indirect parameters, such as accommodation and the need for in-home care pre and post-surgery.

Methods: All INPH-patients who were shunted 2008-2010 in 5 out of 6 neurosurgical centers (covering approximately 80% of the Swedish population) were scrutinized. Matched controls were chosen from the Swedish population index. After exclusion (inability to communicate, age<60 and >85, for patients pre-operatively mini mental state estimation<23), all participants completed a questionnaire and visited their nearest health-care giver. QoL was assessed using the Euroqol EQ-5D-5L scale, a standardized instrument for: 1) self-rated health status in five dimensions; mobility, self-care, activities, pain/discomfort and anxiety, and: 2) self-rated overall health (score 0-100).

Results: 544 individuals participated in the study, 177 patients with INPH (42% females) and 367 controls (37% females). After surgery, patients’ health status in all five dimensions improved significantly (p<0.05). The patients’ health status in all five dimensions was worse than the controls both before and after surgery (p<0.05). Patients rated their overall health lower before than after surgery (45±24SD versus 67±21SD, p<0.001). Controls rated their health higher (79±17SD) than patients both before and after surgery (p<0.001).

Conclusions: Individuals with INPH have a lower QoL than the normal population. Even though surgery considerably improves the patients’ QoL, they still do not reach the same level as the population.

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O-078: LP SHUNT FOR INPH PATIENTS: SURGICAL TECHNIQUE AND COMPLICATIONS.― RETROSPECTIVE REVIEW OF 243 CASES.

Naoyuki Samejima, Nobumasa Kuwana, Akira Watanabe, Yojiro Seki

Department of Neurosurgery, Tokyo Kyosai Hospital, Tokyo, Japan

Abstract:

Background: Recently lumboperitoneal (LP) shunt has become widely used in the treatment for iNPH because of no need for ventricular puncture. We reviewed its complications and investigated the relationship between chronic subdural hematoma (CSDH) and the initial pressure setting.

Methods: A total of consecutive 243 probable iNPH patients underwent LP shunt surgery from April 2009 and May 2013, consisting of 141 men and 102 women with a mean age of 77.8 years. Our surgical techniques include: 1) Upward insertion of the spinal tube through L2/3 via median puncture with occasional paramedian puncture for highly deformed lumbar spine patients; 2) Under 35 degrees bed rotation, without re-sterilization, insertion of the abdominal tube through the rectus abdominis muscle; 3) placement of Codman-Hakim programmable valve with Siphonguard™(CHPV), uppermost pressure of 20cm H2O, on the paraspinal muscle and use of the Quick Reference Table (Miyake) to determine its initial pressure. Since January 2012, we have introduced a tandem shunt method by serially connecting 10cm H2O valve with CHPV for slender patients.

Results: LP shunt was successfully placed in all but a few cervical stenotic cases. Within 1 year after surgery, postoperative complications occurred in 22 (9.1%) out of 243 cases: CSDH that required evacuation in 8 (3.3%); tube occlusion in 3; migration of the abdominal tube in 2; shunt infection in 2; wound dehiscence in 2; and rupture of the spinal tube, valve disruption, abdominal subcutaneous hematoma, lower limb numbness, spinal bleeding, all in 1. As for CSDH, it occurred in 7 out of 144 (4.8%) before January 2012, whereas only 1 out of 99 (1.0%) thereafter (P=0.0562).

Conclusions: Our procedures of LP shunt seem generally acceptable from the viewpoint of complications, especially after the introduction of high pressure setting up to 30cm H2O for slender patients.

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O-079: NORMAL PRESSURE HYDROCEPHALUS: PROGNOSTIC VALUE OF HEIGHT IN PATIENTS TREATED WITH AN IDENTICAL SHUNT SYSTEM

Jesus Aguas1, Victor Rodrigo1, Francisco Estupiñan2, Pere Nogues3, Gloria Villalba1, Javier Villagrasa1, Luis Caral4

1S. Neurocirugía. Hospital Clínico Universitario, Zaragoza, Spain 2Instituto Aragonés de Ciencias de la Salud, Zaragoza, Spain 3Hospital Universitari Arnau de Vilanova, Lleida, Spain 4Hospital Clinic i Provincial, Barcelona, Spain

Background: Normal pressure hydrocephalus (NPH) is a clinical entity frequently managed by means of a CSF-shunt. Hydrodynamic hypotheses consider hydrostatic pressure (as well as height) a very important variable for shunt system function. However, we did not find empirical studies supporting the influence of height on clinical response in the literature. Our objective was to study the prognostic value of height, as a variable related to hydrostatic pressure, when an identical shunt system is used.

Methods: A prospective series of 61 idiopathic NPH cases was analyzed. All cases where shunted by means of a ventricle- peritoneal system with a 100mmH20 opening pressure valve. Anthropometric, clinical, radiological and pressure variables were registered as well as delay for treatment, improvement and complications.

Results: 78,7% of cases improved after shunt. This group of patients were significantly taller (p=0.005) than the group without response (median value 165 cm versus 152 cm). There was also a significant correlation between height and ventricular size decrease after shunt.

Conclusions: In our series opening valve pressure was a constant (100mmHg) and we could consequently focus on the effect of the hydrostatic pressure (height). Moreover, we found a positive predictive value for taller patients, probably because we had selected an opening pressure especially suitable for them. Current gravitiational valve shunt systems also recommend considering patient height when customising the system. Our study empirically supports this idea.

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O-080: WEIGHT AND ABDOMINAL-PRESSURE INFLUENCED SHUNT TROUBLE (WAIST) IN SHUNTED NORMAL PRESSURE HYDROCEPHALIC PATIENTS: WHOLE PRESSURE ANALYSIS FOR OF SHUNT SYSTEM

Yoshinaga Kajimoto1, Tomohisa Oomura1, Hiroji Miyake2, Toshihiko Kuroiwa1

1Osaka Medical College, Takatsuki, Japan 2Nishinomiya Kyouritu hospital, Nishinomiya, Japan

Background: Intra-abdominal pressure (IAP), one of the determinants of CSF (cerebral spinal fluid) shunt function, is dependent on the degree of obesity. Theoretically body weight change inducing CSF shunt malfunction can be expected. We have experienced shunt troubles caused by the body weight changes in patients and clarified its mechanism by analyzing whole pressure parameters of shunt function to propose a practical formula for the re-adjustment of the shunt valve.

Methods: Five cases were analyzed; four cases with weight gain induced underdrainage (UD) and one case with weight loss induced overdrainage (OD). We measured their whole pressures; IAP, intra-cranial pressure (ICP), perfusion pressure (PP), and hydrostatic pressure (HP) before and after body weight change and after the re-adjustment of their programmable valve pressure (VP).

Results: IAP and its validation strongly associated with body mass index. Body weight gain (6.8kg) elevated both IAP (8.8 mmHg) and ICP (6.8 mmHg). Ten kg of weight loss decreased both IAP and ICP by 5 mmHg respectively. In the cases of UD, after reducing the VP of 4.5 mmHg, ICP and clinical symptom of gait disturbance were quickly recovered. In the case of OD, the hematoma had disappeared with increased VP by 6 mmHg. The range of upright ICP with normal drainage, which corresponded to therapeutic windows of ICP, ranged from -7 to -14 mmHg.

Conclusion: Body weight change directly alters not only IAP but also ICP in shunted hydrocephalic patients. If ICP value shows deviations from therapeutic window, OD or UD can be induced. However, inadequate ICP and symptoms can be rectified by valve re-adjustment. When symptoms worsen with body weight change, weight and abdominal-pressure influencing shunt trouble (WAIST) should be noticed and valve re-adjustment is recommended.

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OF-081: HEALTH-RELATED QUALITY OF LIFE OF PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Antti Junkkari1, Harri Sintonen,2 Ossi Nerg1, Anne Koivisto1, Risto Roine3, Heimo Viinamäki4, Juha Jääskeläinen1, Ville Leinonen1

1Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland 2Department of Public Health Science, University of Helsinki, Helsinki Finland 3Hospital District of Helsinki and Uusimaa, Uusimaa 4Department of Psychiatry, Institute of Clinical Medicine, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland

Background: Idiopathic normal pressure hydrocephalus (iNPH) impairs Health-Related Quality of Life (HRQoL), but previous studies have not compared the HRQoL of iNPH patients with that of the general population. In addition to this, our study explored factors affecting HRQoL in iNPH patients and the usefulness of the generic 15D HRQoL instrument in the evaluation of iNPH.

Methods: The HRQoL was measured by the 15D instrument from 132 patients – diagnosed with iNPH by clinical and radiological examination (Kuopio University Hospital NPH Registry www.uef.fi/nph). The severity of iNPH symptoms was measured with the iNPH Grading Scale (INPHGS, 0-12), depressive symptoms with the Beck Depression Inventory II (BDI-II), and cognition impairment with the Mini- Mental State Examination.

Results: The mean (SD) 15D score (on a 0- 1 scale) of patients with iNPH was significantly lower than that of an age- and gender standardized sample of the general population [0.718 (0.103) vs. 0.870 (0.106); p < 0.001]. On the majority of the 15D dimensions the iNPH patients showed lower mean values than the general population. There were significant group differences in the mean 15D score (p=0.003) and in the mean dimension level values between iNPH patients without depressive symptoms and those with moderate or severe depressive symptoms. According to stepwise multiple linear regression analysis a higher total iNPHGS score (b=-0.62, p<0.001) and a higher BDI-II total score (b=-0.201, p=0.025) predicted a lower 15D score and in combination explained 50.6% of the variance in the 15D score (R2=0.506, p <0.001).

Conclusions: iNPH reduces patients HRQoL on multiple dimensions similarly than other chronic disease. The main comorbidity impairing HRQoL of iNPH patients is depression, but only when it is moderate or severe. A higher MMSE score was associated with a higher 15D score and a lower iNPHGS score, but no significant difference was observed between groups categorized by level of cognition. The 15D portrayed HRQoL dimensions affected by iNPH in a similar way as iNPHGS, and thus it is a useful tool for treatment evaluation and cost-effectiveness analysis.

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OF-082: CLINICAL OUTCOMES AND COMPLICATIONS AFTER VENTRICULOATRIAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS: A LARGE MULTICENTER STUDY

Ignacio Jusue-Torres1, Mira Patel1, Jamie Hoffberger1, Juan Ramon-Cuellar2, Fernando Hakim1, Daniele Rigamonti1

1Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA 2Department of Neurosurgery. Santa Fe de Bogota Foundation. Bogota D.C., Colombia

Background: Ventriculoatrial (VA) shunting has not historically been the first-line treatment for idiopathic normal pressure hydrocephalus (iNPH), due to surgeon preference, technical experience, and potential cardiopulmonary complications. There is conflicting evidence regarding the risks and outcomes associated with VA shunting compared to other treatments. We present a large, multi-center study evaluating the clinical outcomes and complications of iNPH treated with VA shunt.

Methods: We retrospectively reviewed patients from two institutions with a diagnosis of iNPH who received VA shunting between 2003-2013 and who had no prior history of shunting. Simultaneously, a systematic search retrieved 18 studies published between 1971 and 2014 with 906 patients who had VA for iNPH. Data on demographics, comorbidity index, surgical history, post-operative complications and surgical revisions were collected.

Results: A total of 121 patients (median age=74 years) met the inclusion criteria. Median follow-up was 14 months. There were post-operative complications in 25.6%, with subdural hematoma/hygroma the most prevalent complication (15.7%). There were no cardiopulmonary complications. There were no significant differences in demographics, comorbidity, time to symptom onset, or follow-up time between those who had complications and those who did not, and between those who required surgical revision and those who did not. Median time to revision was 60 months, 8.3% patients underwent revision in our study compared to 23.7% from the literature review. The probability of being free of surgical revision at one and five years was 0.94 and 0.82, respectively.

Conclusions: We show that VA shunting does not carry with it an inherently high risk of complication, including cardiopulmonary complication. The rate of revision of VA shunting is low in our cohort. Both rates of complications and surgical revisions indicate that VA shunt indication should not be limited as treatment of iNPH after ventriculoperitoneal shunt failure.

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OF-083: FAMILIAL NORMAL PRESSURE HYDROCEPHALUS: A NOVEL SUBGROUP

Takeo Kato1, Yoshimi Takahashi1, Shinji Ono2, Naoyuki Samejima3, Masakazu Miyajima4, Kazuya Aoki5, Shinya Yamada6, N Kuwana1, H Arai1.

1Department of Neurology, Hematology, Metabolism, Endocrinology and Diabetology, Yamagata University Faculty of Medicine, Yamagata, Japan 2Department of Psychiatry, Nagasaki University Graduate School of Medicine, Nagasaki, Japan 3Department of Neurosurgery, Tokyo Kyosai Hospital, Tokyo, Japan 4Department of Neurosurgery, Juntendo University, Tokyo, Japan 5Department of Neurosurgery, Hokushin-Kai Megumino Hospital, Hokkaido, Japan 6Department of Neurosurgery, Toshiba Rinkan Hospital, Kanagawa, Japan

Background: Normal pressure hydrocephalus (NPH) is classified into two subgroups: idiopathic NPH (iNPH) and secondary NPH (sNPH). sNPH occurs several weeks or months after subarachnoid hemorrhage, meningitis, traumatic brain injuries, or certain other illnesses. iNPH occurs without any preceding diseases, and its cause remains undetermined. Little has been described about familial occurrence of NPH. Here we report some families with NPH.

Methods: We searched for NPH patients with a family history of the disease in Japan, and found two large families with NPH and seven pairs of siblings with NPH.

Results: Those patients with familial NPH (fNPH) had one or more symptoms of the NPH triad, showed DESH (disproportionately enlarged subarachnoid-space hydrocephalus) on brain MRI, and were shunt-responsive. The patients with fNPH were indistinguishable from those of iNPH on neurological and brain MRI examinations.

Conclusions: We found a considerable number of patients with fNPH, a novel subgroup of NPH. Therefore, NPH should be classified into three subgroups: iNPH, sNPH, and fNPH.

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OF-084: CLINICAL OUTCOMES AND COMPLICATIONS AFTER VENTRICULOATRIAL SHUNTING FOR IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Mira Patel, Ignacio Jusue-Torres, Jamie Hoffberger, Daniele Rigamonti

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

Background: Ventriculoatrial (VA) shunting has not historically been the first-line treatment for idiopathic normal pressure hydrocephalus (iNPH), due to surgeon preference, technical experience, and potential cardiopulmonary complications. There is conflicting evidence regarding the risks and outcomes associated with VA shunting versus other treatments. We study the clinical outcomes and complications of iNPH treated with VA shunt.

Methods: We retrospectively reviewed patients with a diagnosis of iNPH who received VA shunting between 2003-2013 and who had no history of previous shunting. Data on demographics, comorbidity index, post-operative complications and surgical revisions were collected. Clinical data including iNPH grading scale (INPHGS), mini-mental status exam (MMSE), Evan’s ratio, Timed Up-and-Go (TUG) and Tinetti scores were collected at baseline and at last follow-up (LFU). Descriptive statistics, non-parametric univariate analyses and Spearman’s correlation were performed.

Results: Sixty-nine patients (median age=73.5 years) met the inclusion criteria. Median follow-up was 12 (6-21.5) months. Only three (4.34%) patients showed worsening in INPHGS at LFU. Two patients (2.90%) developed shunt obstruction and one patient infection (1.45%). There were no cardiopulmonary complications. Tinetti, TUG, MMSE, and INPHGS showed significant improvement at LFU compared to baseline (p<0.05). Improvement in MMSE at LFU (p=0.04) was correlated with improvement in INPHGS. An improvement in TUG was correlated with the absence of complications (p=0.05), and the presence of complications was significantly correlated with increased number of revisions (p<0.001). The absence of revision (p=0.02) at LFU was correlated with better INPHGS at LFU.

Conclusions: Our data suggest that patients with untreated iNPH can obtain significant clinical improvement from VA shunt, with a low rate of post-operative shunt obstruction and infection and no cardiopulmonary complications. While VA shunting improves gait, cognition and urinary incontinence over time, the presence of complications that may lead to revisions are both associated with negative clinical outcomes in iNPH.

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OF-085: THE LAUNCESTON IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS PREVALENCE STUDY: A TREATABLE DEMENTIA, MISSED DIAGNOSIS

George Razay1, Melissa Razay1, Iain Robertson2

1Launceston General Hospital, Launceston, Australia 2School of Human Life Sciences, University of Tasmania, Launceston

Background: Idiopathic Normal Pressure Hydrocephalus (iNPH) is one of the few treatable forms of dementia, but it is notoriously difficult to diagnose in the elderly. There have been few studies addressing the prevalence of the condition among patients with cognitive impairment. We have, therefore, investigated the prevalence of iNPH amongst patients with cognitive impairment attending the Memory Disorders Clinic in Launceston, Tasmania, Australia.

Mehtods: Since 2010, we have completed a prospective cohort study of 400 consecutive patients with memory problems from Northern Tasmania. Patients were referred by General Practitioners and Hospital Physicians. The diagnosis of iNPH was based on the presence of memory impairment or dementia, and/or balance/gait disorder, the presence of prominent ventricles regardless of cerebral atrophy on MRI of the brain, and ventricular stasis on CSF Flow Study (Cisternography).

Results: 187 men and 213 women participated in the study, mean age 74.2 years (range 32-95 years), mean mini-mental state examination (MMSE) score 23.3. 215 (54%) patients were diagnosed with mild cognitive impairment (MCI), of whom 29 (14%) had iNPH. There were 18 (62%) men and 11 (38%) women, age 74 y (57- 88) and MMSE score 27 (25-30). 185 (46%) were diagnosed with dementia, of whom 35 (19%) had iNPH. There were 21 (60%) men and 14 (40%) women, age 80.4 y (62-92) and MMSE 19.7 (14-27). 33 (52%) of patients with iNPH had ventriculo-peritoneal shunt surgery, of whom 21(64%) had MCI, 14 men and 7 women, age 70.6 (44-86), MMSE 27.2 (25-29), and 12 (36%) had dementia, 7 men and 5 women, age 80 y (71-90), MMSE 19.9 (11-27).

Conclusion: The prevalence of iNPH among patients with cognitive impairment is probably more common than previously thought. This is important because many patients without shunting might be condemned for years of disabilities and institutionalisation.

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OF-086: BASIC CONCEPT AND USEFULNESS OF INITIAL VALVE PRESSURE SETTING QUICK REFERENCE TABLE BY WEIGHT AND HEIGHT

Yoshinaga Kajimoto1, Tomohisa Oomura1, Hiroji Miyake2, Toshihiko Kuroiwa1

1Osaka Medical College, Takatsuki, Japan 2Nishinomiya Kyouritu hospital, Nishinomiya, Japan

Background: Quick and reliable setting of programmable pressure valves (PPVs) is important in the treatment of idiopathic normal pressure hydrocephalus (iNPH). A new quick reference table (QRT) was developed for improved PPV control and outcome. Shunt control can be based on the pressure environment in the sitting condition, given as hydrostatic pressure (HP) = intracranial pressure + PPV setting + intra-abdominal pressure (IAP). Using this relationship, and estimating HP and IAP from the patient’s height and body mass index, respectively, a QRT was designed, consisting of a matrix of the patient’s height and weight.

Methods: To assess the usefulness of a QRT for initial pressure valve setting in iNPH patients who participated in the Study for iNPH on Neurological Improvement (SINPHONI). One hundred registered patients were treated with ventriculoperitoneal shunts using Codman-Hakim programmable valves (CHPVs). The initial CHPV setting was decided by QRT algorithm. Shunt effectiveness, complications, and the number of CHPV readjustments during follow-up periods were investigated.

Results: Eighty patients were considered better than shunt responders (more than 1 point improvement in modified Rankin scale at any follow-up period). Readjustments of CHPVs within 3 months after treatment with ventriculoperitoneal shunt were performed 56 times in 44 cases (44%, 0.56 times/patient). Burrhole irrigation of subdural hematoma was necessary in only 1 case.

Conclusions: In conclusion, using of QRT algorithm was linked to a decrease in postoperative CHPV re-adjustments and serious overdrainage complications during the follow-up period. The QRT algorithm is an easy, safe, effective, and scientific method for determining the initial CHPV pressure setting in iNPH patients.

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OF-087: LONG TERM BENEFIT OF VP SHUNT INSERTION IN PATIENTS WITH NORMAL PRESSURE HYDROCEPHALUS

Flavia Somavilla, Ahmed Toma, Amna Farrukh, Samir Matloob, Patricia Haylock – Vize, Mustafa Anjari, Simon Thompson, Laurence Watkins

National Hospital for Neurology and Neurosurgery, Queen’s Square, United Kingdom

Background: VP shunt insertion is the recognised treatment for patients diagnosed with Normal Pressure Hydrocephalus (NPH) to obtain improvement in walking ability, memory and urinary disturbance. To validate the long term benefits of shunt insertion in NPH we looked at postoperative outcome and complication rates in our unit.

Methods: Data was analysed retrospectively. 60 patients with diagnosis of NPH were identified who underwent VP shunt insertion between July 2004 and November 2010. Information was obtained from postoperative clinic appointments with average follow up of 4.85 years (StdDev 1.6y). Change in mobility was used as parameter for postoperative outcome and measured in 35 cases (58%) with a pre- and postoperative 10 metre walking test. Data regarding type of shunt, initial shunt setting and shunt adjustment was recorded. Information about complications and type of complication was collected.

Results: Out of 60 patients aged 55 – 89 (75 +/- 8.3) we recorded improvement in 38 patients (63,3%) within 3 months after shunt insertion. After shunt adjustment 50 patients (83%) experienced improvement of mobility. The average length of benefit after surgery was recorded 49.88 months (StdDev 23.1). Length of shunt benefit was determined by either decline in mobility or death. Complications included 5 patients developing chronic subdural haematoma (8.3%) and 8 requiring shunt revision (13.3%). No case of shunt infection or immediate death was identified.

Conclusion: The majority of patients (83%) experienced improvement of symptoms after shunt insertion with 4.1 years average length of benefit. Positive outcome did not correlate with age at insertion or gender. Revision did not interfere with positive outcome. Based on our experience, VP shunt insertion has a significant benefit on quality of life in this patient group.

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OF-088: COMPUTERIZED NEUROPSYCHOLOGICAL TESTING IN iNPH BEFORE AND AFTER SHUNT SURGERY

Anders Behrens1, Anders Eklund2, Eva Elgh1 Jan Malm1

1Department of Clinical Neuroscience, Umeå, Sweden 2Department of Radiation Sciences, Umeå, Sweden

Background: A novel computerized neuropsychological test battery has been developed to provide the clinician with a standardized tool assessing the cognitive domains specific for idiopathic normal pressure hydrocephalus (INPH). The conventional neuropsychological tests most often used in INPH were identified in a literature review, and adapted to a computerized format. Validity, reliability and feasibility for testing in INPH have previously been established. The aim of this study was to determine if implemented tests were sensitive to improvement after shunt surgery in a group with INPH.

Methods: Twenty-eight patients with INPH (age 73,7 y, Mini mental state examination (MMSE) 25 points) were given the computerized test before and after shunt surgery. The scores were compared to healthy elderly (n=44, age 69,3 y, MMSE>28 points). * indicates significant improvement (P<0.05).

Results: Mean time from surgery to follow up testing was 124 days. A subset of tests improved after shunt surgery. Mean improvement of scores from baseline: Two-Choice reaction test, 18%*, Stroop congruent words, 12%*, Stroop incongruent words, (n=17) 13%*, 10-Word List (sum of 3 trials), 19%*, Four-finger tapping, (n=10) 39%*. No significant change was seen in the Trail making tests A and B and the delayed recall and recognition tests. At baseline, the INPH patients performed significantly worse than the healthy elderly on all tests.

Conclusions: Five of the implemented tests showed improvement after surgery. All tests showed impairment at baseline compared to healthy elderly. The practical, self-administrating, validated and free of charge computerized test battery has a potential to be useful in the cognitive assessment of INPH patients.

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O-089: HYDROCEPHALUS IN ADULTS WITH COMMUNITY ACQUIRED BACTERIAL MENINGITIS

Ivan Pelegrin1, Roger Bayston2, Javier Ariza1, Pedre Viladrich1, Carmen Cabellos1

1Infectious Diseases Department. IDIBELL-Hospital Universitari Bellvitge, Barcelona, Spain. 2School of Medicine, University of Nottingham, United Kingdom

Background: To evaluate occurrence, risk factors, treatment and outcome in adults with hydrocephalus complicating community acquired bacterial meningitis (C-ABM).

Methods: Observational prospective study of all episodes of C-ABM between January 1977 and January 2011 in patients ≥ 16 years old. We retrospectively selected those who developed hydrocephalus complicating C-ABM comparing them with those who did not develop. Analysis of risk factors for development of hydrocephalus was performed.

Results: Hydrocephalus was diagnosed in 22 of 790 (3%) C-ABM patients. Mean age was 67 years (range 38-94) in the hydrocephalus C-ABM group and 49 years (range 16-93) in the non-hydrocephalus C-ABM group. The most common bacterial causes were Listeria monocytogenes 7/22 (32%), Streptococcus pneumoniae 7/22 (32%) among the hydrocephalus C-ABM group and Neisseria. meningitidis 310/790 (39%), S. pneumoniae 261/790 (33%), L. monocytogenes 56/790 (7%) among C-ABM patients without hydrocephalus. Time to illness was >48h in 14/22 (63%) in the hydrocephalus C-ABM group and in 184/768 (24%) of the other group. 10/22 (46%) patients were diagnosed at admission and 12/22 (54%) during hospital stay [median 6 days (IQR 3.5-11)]. Age (OR 1.049, CI95 %: 1.018-1081), time to illness >48h (OR 4.293, CI95%: 1.726-10.678) and L. monocytogenes (OR 2.798, CI95%:1.022-7.656) were independent risk factors for development of hydrocephalus. 7 patients underwent placement of an external ventricular drain (5 died) and 4 a definitive CSF shunt (2 after EVD). Overall mortality and neurologic sequelae were higher in the hydrocephalus C-ABM group 11/22 (50%) vs 108/768 (14%) (p<0.001) and 6/11 (55%) vs 89/660 (13%) respectively. Hydrocephalus was an independent risk factor for mortality (OR 3.247 IC 95 % 1.045-10.085).

Conclusions: Hydrocephalus complicating C-ABM was more frequent in the elderly, in those who presented a time to illness > 48h and in L. monocytogenes meningitis. Hydrocephalus was related to worse outcome in C-ABM adult patients.

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O-090: AN UNDERECOGNIZED CAUSE OF HYDROCEPHALUS: ADULT CHOROID PLEXUS HYPERPLASIA. CASE SERIES

Daniele Rigamonti, Jacob Cox, Ignacio Jusue-Torres, Shiv Gaglani, Michael Haynes, Ari Blitz

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA

Background: Obstructive hydrocephalus is a potentially life-threatening condition in which blockage in the cerebral ventricular system leads to increasing volumes of cerebrospinal fluid (CSF) in the ventricles, inducing increasing intracranial pressure and pathologically enlarged ventricular size. Choroid plexus hyperplasia (CPH) is a known and exceedingly rare cause of pediatric hydrocephalus with a mean age at diagnosis of 32-month. There are no reported cases in adults. Pediatric CPH is characterized by abnormally diffuse enlarged but morphologically normal choroid plexus (CP) that overproduces CSF. We describe the presentation of five patients who are the first reported adults with CPH-inducing obstructive hydrocephalus at the foramen of Monro and preliminary results of treatment of CPH with Acetazolamide.

Case Descriptions: From August 2010 to January 2014, five patients with a mean age of 50 year-old were evaluated for suspected hydrocephalus and were found to have abnormally large CP obstructing one or both foramina of Monro on magnetic resonance imaging (MRI). Four presented with bilateral ventriculomegaly, while the fifth presented with unilateral ventriculomegaly and bowing of the septum pellucidum. All patients had normal third and fourth ventricles on MRI at presentation and no appreciative CSF flow through the obstructed foramina of Monro on cine MRI sequences.

Discussion: Other causes of obstructive hydrocephalus related to CP tissue include: choroid plexus papilloma, choroid plexus carcinoma, and choroid plexus cysts. Our cases are epidemiologically, radiologically, anatomical locationally and pathologically distinct from these conditions. In one patient, treatment with the Acetazolamide showed nearly complete resolution of symptoms. Follow-up cine MRI sequences evidenced biphasic CSF flow throughout the ventricular system associated with CP regression within 16 months. This suggests that Acetazolamide could be an effective, non-invasive treatment for adult CPH.

Conclusion: This is a never-before described condition in adults that may respond to Acetazolamide. We denominate it adult choroid plexus hyperplasia.

92 ADULT HYDROCEPHALUS

O-091: YOUNG ADULT IDIOPATHIC AQUEDUCT STENOSIS SPECTRUM; FOCUSING ON MEDICAL HISTORY AND CHRONOLOGICAL RADIOLOGICAL IMAGES

Daisuke Kita, Yasuhiko Hayashi, Issei Fukui, Yutaka Hayashi, Masaaki Hashimoto

Department of Neurosurgery, Kanazawa University Hospital, Kanazawa, Japan

Introduction: Idiopathic triventriculomegaly (TVM) found in young adulthood has been recognized as long-standing overt ventriculomegaly in adults (LOVA) (Oi. J Neurosurg. 2000) or late-onset idiopathic aqueductal stenosis (LIAS) (Fukuhara. Surg Neurol. 2001). It has been suggested that macrocephaly and marked TVM usually seen in LOVA may indicate this condition most likely begins in infancy, whereas the onset of LIAS is undetermined and may overlap with that of LOVA. In order to clarify these concepts, we discuss three cases of young adult AS of which past medical history including radiological images was available.

Cases: 16 (case 1), 17 (case 2), and 27 (case 3) years old males with symptomatic AS were taken MRI/CT previously because of syncope (15 y.o.), neurohypophysitis (3 y.o.), and headache (15 y.o.), respectively. TVM was mild in case 1 and 2, while marked in case 3. In case 2, TVM had not been detected until he was 6 years old. Macrocephaly was pointed out in case 3. Medical history of intracranial inflammation was detected in case 2 (3 y.o., neurohypophysitis) and case 3 (6 m.o., meningitis).

Discussion: Considering the beginning of AS, case 3 was compatible to LOVA. Mild TVM without macrocephaly in case 1 and 2 suggested that their conditions might be more recent event compared with case 3, which was demonstrated radiologically in case 2. Moreover, presence of inflammatory process in central nervous system in distinct age was closely associated with the presence of macrocephaly and with the degree of TVM, as shown in case 2 and 3.

Conclusion: In young adult non-tumoral AS, age of the preceding intracranial inflammation may be a key to recognize the difference between LOVA and so-called LIAS. Despite small numbers, presented cases with detailed past medical information would provide important insight into development of young adult idiopathic AS spectrum.

ADULT HYDROCEPHALUS

O-092: NEGATIVE PRESSURE HYDROCEPHALUS: POSSIBLE AETIOLOGY, CSF HYDRODYNAMICS AND PRINCIPLES OF SUCCESSFUL TREATMENT

Asim Mujic, Benjamin Hunn, Asad Sheikh, Andrew Hunn, Albert Erasmus, Jens Peters-Willke, Arvind Dubey

Royal Hobart Hospital, Hobart, Australia

Background: Negative-pressure hydrocephalus (NegPH) is a rare clinical condition that manifests enlarged ventricles and symptoms consistent with increased intracranial pressure (ICP) in the setting of negative ICP. In this updated series we present nine patients with statistically significant clinical, manometric and radiological improvement following treatment of negative pressure hydrocephalus. The critical points in our work are importance of early recognition and prompt treatment of negative pressure hydrocephalus.

Methods: This study is a retrospective audit of nine cases of negative pressure hydrocephalus occurring at the Royal Hobart Hospital between 2006 and 2013.

Results: Nine cases of NegPH were identified. All patients had at least one preceding intracranial procedure (mean number of procedures 3.0). Following drainage of CSF at negative (subatmospheric) pressure, all 9 patients demonstrated clinical improvement. Mean increase in Glasgow Coma Score was 4.6, p = 0.001 and mean increases in ICP was 8.5, p<0.001. Mean delay in recognition of negative pressure hydrocephalus was 1.8 days. Mean length of follow up was 471.8 days. Five patients returned to pre-morbid neurological function, three had reduction in functioning attributable to their initial presentation (not negative pressure hydrocephalus) and one had died of unknown cause. In addition, we explored the hypothesis of Filippidis and colleagues that suggests that a CSF leak and establishment of transmantle pressure gradient between the ventricles and cortical subarachnoid space plays an important role in the development of a negative pressure hydrocephalic state. Iatrogenic CSF leak after craniotomy or shunt insertion may result in a rapid lowering of CSF pressure in the subarachnoid space. Low pressure resulting in a loss of transmantle pressure gradient in which ventriculomegaly may persist with negative ICP.

Conclusions: Negative-pressure hydrocephalus is a rare and possibly unrecognised syndrome that can be successfully treated by timely external ventricular drainage titrated to maintain CSF flow, and subsequent low-pressure ventriculoperitoneal shunting.

93 ADULT HYDROCEPHALUS

O-093: MANAGEMENT OF PERSISTENT ORTHOSTATIC HEADACHE: THE ROLE OF INTRACRANIAL PRESSURE MONITORING, INFUSION STUDIES AND IMAGING

Mustafa Anjari, Ahmed Toma, Simon Thompson, Samir Matloob, Amna Farrukhm, Patricia Haylock-Vize, Flavia Somavilla, Laurence Watkins

National Hospital for Neurology and Neurosurgery, Queens Square, London, United Kingdom

Background: Orthostatic headache is a well described entity that is often debilitating. It is characterised by postural headaches and can be associated with nausea and vomiting, neck stiffness and alterations in vision and hearing. The aim of this study was to assess the role of intracranial pressure (ICP) monitoring, infusion studies and imaging in guiding the management of patients with persistent orthostatic headache.

Methods: A retrospective case series was performed at our unit of all patients diagnosed with orthostatic headache between 2009 and 2014. A standard diagnostic and management protocol was followed. This consisted of ICP monitoring, followed by cerebrospinal fluid (CSF) infusion studies combined with CT myelogram and cisternogram. Some patients underwent treatment with blood patches following confirmation of a low ICP.

Results: Thirteen patients were identified (3 male) with a mean [range] age of 50.5 [22-77] years. Symptom duration ranged from 2-10 years. Seven patients had multiple ineffective epidural blood patches and five had evidence of CSF leak on myelogram studies. Median ICP per patient ranged from -5.15 to 4.98mmHg with a mean of 0.78mmHg (normal range 8.63-13.13mmHg [Ekstedt, 1978]). This did not clearly correlate with the recumbent CSF pressures measured during infusion studies (R=0.29). CSF infusion studies demonstrated a mean [range] CSF outflow resistance of 9.15 [1.78-22.3] mmHg/ml/min (normal range 4.81-10.4 mmHg/ml/min). No patients had complications as a result of the investigation protocol.

Conclusions: Our experience suggests that orthostatic headache remains a difficult entity to treat. It has been suggested that these headaches usually resolve spontaneously without treatment or at most with a blood patch, but in this group patients continued to have symptoms despite a range of therapies. Relying on recumbent CSF pressures alone missed low ICP in 6/13 patients. This suggests that adopting a standard protocol might facilitate diagnosis and treatment in patients with orthostatic headaches.

94 Poster Abstracts

Saturday 6th September 8.00 - 18.00

NEURORADIOLOGY

P094: IMPACT OF SHUNT PLACEMENT IN CSF DYNAMICS

Cyrille Capel1, Olivier Balédent2, Jérome Hodel3, Marc Baroncini4

1Université de Picardie Jules Verne, Amiens, France 2BioFlow Image, Amiens, France 3Radiology, Lille, France 4Neurosurgery, Lille, France Background: Adult hydrocephalus is related to CSF flows disorders. Phase contrast MRI (PC-MRI) is the unique tool to measure CSF oscillations in vivo during the cardiac cycle. CSF hydrodynamic alteration has been described helpful to select hydrocephalus patients for shunt. Few things are known about CSF hydrodynamic evolution after shunt placement. The aim of this work was to compare CSF hydrodynamic before and after shunt placement with a continuous flow valve.

Methods: 16 hydrocephalus patients (71.6 ± 8.84 years; [52.2 - 86.5]) who improved after shunt placement with a grade 0 or 1 on Stein and Langfitt Scale for assessment of shunt outcome were included. All of them underwent PC MRI before shunt placement and 6 months after surgery. CSF stroke volumes were calculated during the cardiac cycle in the aqueduct (SVaqu) and into the C2C3 subarachnoid spaces (SVspine).

Results: SVaqu decreased of 28% after surgery (p=0.002) (preoperative SVaqu=231 ± 111μL; postoperative SVaqu=196 ± 91μL). Whereas SVaqu increased moderately in two cases it also decreased more than 50% in two others cases. Finally SVaqu decreased less than 50% in the 12 other cases. SVspine did not change after surgery (p=0.55) (preoperative SVspine=522 ± 238μL; postoperative SVspine=499 ± 227μL).

Conclusions: Shunt placement did not change spinal subarachnoid CSF dynamic. It mainly decreases intraventricular CSF dynamic. Nevertheless because intraventricular hydrodynamic still remained abnormal and may slightly increase in shunt patient responders, SVaqu can’t be used alone to predict shunt dysfunction.

NEURORADIOLOGY

P095: IS DESH DISTINCTIVE OF INPH?

Wataru Narita, Tetsuro Ishihara, Toru Baba, Osamu Iizuka, Yoshiyuki Nishio, Minoru Matsuda, Etsuro Mori

Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan Background: Normal pressure hydrocephalus (NPH) is categorized into secondary (sNPH) and idiopathic (iNPH). Disproportionately Enlarged Subarachnoid-space Hydrocephalus (DESH) has been identified as a characteristic feature of iNPH. However, it remains uncertain whether DESH is specific for iNPH, or does not appear in sNPH. It is also undetermined what proportion of iNPH is not DESH. Here we addressed these questions.

Methods: The subjects were 185 patients who consecutively admitted to our department with suspected NPH of undetermined etiology from January 2006 to April 2013. The brain magnetic resonance imaging or computed tomography scans were evaluated for ventricles, Sylvian fissures (SF), and high convexity/midline subarachnoid spaces (HC). Findings were classified into three categories: DESH (ventriculomegaly, tight HC, dilatated SF), incomplete DESH (in addition to ventriculomegaly, disproportional distribution of CSF between HC and SF), and non-DESH (other than the above). non- DESH was further classified whether SF is constricted or not.

Results: Of 185 patients, 165 patients were iNPH. The proportions of DESH, incomplete DESH, and non-DESH were 60.0% (N=99), 33.9% (N=56), and 6.1% (N=10), respectively. None showed constricted SF. Of 20 patients with sNPH, the underlying etiology included post-ICH (N=3), post-TBI (N=1), brain or spinal cord tumor (N=5), pre-pontine cisternal trapping (N=7)，aqueductal stenosis (N=2)，and Blake’s pouch cyst (N=2). In sNPH, DESH was found in only 1 patient with acoustic neurinoma. Incomplete DESH was present in 45.0% (N=9). Non-DESH with constricted SF was present in 50.0% (N=10), and was associated mostly with occlusive etiologies.

Conclusions: DESH is specific for iNPH. Incomplete DESH is somewhat equivocal, but is a prominent feature of iNPH. Non- DESH with constricted SF was likely to indicate occlusive etiologies. In cases of absence or insufficiency of DESH features, further evaluation is recommended to detect underlying etiology and occlusion site.

95 NEURORADIOLOGY

P096: SYRINGOMYELIA: A PRACTICAL, CLINICAL CONCEPT FOR CLASSIFICATION Christoffer Blegvad1, Joachim André Grotenhuis2, Marianne Juhler1

1University Clinic of Neurosurgery 2092, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark 2Department of Neurosurgery, Radboud University Medical Centre, Nijmegen, The Netherlands

Background: The term syringomyelia describes many pathogenetically different disorders and a variety of attempts to group these based on different criteria have been proposed in the literature. As a consequence a lack of consensus regarding classification and terminology exists. This inconsistency extends to the ICD-10 classification of diseases in regards to syringomyelia (G95.0) and hydromyelia (Q06.4). We propose a new unifying concept for classification that also incorporates diagnostics and treatment.

Methods: The PubMed online database was used to gain a general overview of the existing pathogenetic theories in relation to syringomyelia. Illustrative cases at our department were included and similar cases of the literature were found using the PubMed database. All material was reviewed with main focus on the classification and terminology used.

Results: Despite syringomyelia (G95.0) and hydromyelia (Q06.4) exist as independent ICD-10 entities, we have shown that the use of classifying terminology for fluid filled cavities in the spinal cord is indiscriminate and inconsistent. Even though a general agreement on the believed pathogenetic mechanism exists, and the general treatment methods are used in accordance with this mechanism, the terminology fails to function as a simple and universal link between theory and treatment.

Conclusions: We propose a new causal concept for an ICD-classification with syringomyelia (G95.0) as the only describing terminology, thus abandoning the use of hydromyelia (Q06.4). Syringomyelia is divided into five subgroups according to the associated pathologies. The classification is based on applied diagnostics and serves as a clinical guidance for treatment.

NEURORADIOLOGY

P097: MRI WITH INTRAVENTRICULAR GADOLINIUM FOR DELINEATING COMPLEX MULTI-LOCULATED HYDROCEPHALUS

Kevin Tsang1,3, Mathuri Sakthithasan1, Neil Stoodley2, Greg Fellows3, Richard Edwards3

1Department of Neurosurgery, North Bristol NHS Trust, Bristol, United Kingdom 2Department of Neuroradiology, North Bristol, NHS Trust, Bristol, United Kingdom 3Department of Paediatric Neurosurgery, Bristol Royal Hospital for Children, Bristol, United Kingdom

Introduction: Gadolinium is a commonly used intravenous contrast medium for MR imaging. It is well-tolerated with rare reactions of 1 in 10 000. It can be used intrathecally for myelography and a few case reports describe its direct injection into intracranial arachnoid cysts. However there has been no reported intraventricular injection of gadolinium for MRI.

Case report: An 8 year-old boy with a history of post-hemorrhagic hydrocephalus presented with recurrent nocturnal seizures following a minor head injury. He had bilateral ventriculoperitoneal shunts and multiple previous revisions. Initial CT imaging showed possible subtle enlargement of the left occipital horn of uncertain significance but delayed imaging showed enlargement of the right temporal and occipital horns with no further change on the left side. It was not clear whether the right-sided or both catheters needed revision. It was felt contrast MR Ventriculography would facilitate this decision. Gadolinium was uneventfully injected intraventricularly via a separate ventricular access device 5 minutes prior to an MRI scan. The scan showed gadolinium travelling from the right frontal horn to the left lateral ventricle and down the left-sided shunt, but not into the right occipital and temporal horns or the right-sided shunt. A new right-sided shunt was therefore inserted directly into the right temporal horn. The child recovered fully and post-operative CT scan showed complete resolution of the hydrocephalus.

Conclusion: Without the contrast study, a decision to insert a new right-sided ventricular catheter into the body or frontal horn of the right lateral ventricle, which was already being drained by the left-sided shunt, and also to explore the (functioning) left-sided shunt may have been erroneously made. This case report shows that Gadolinium MR Ventriculography facilitates complex decision making in patients with multi-loculated hydrocephalus.

96 NEURORADIOLOGY

P098: VOLUMETRIC ANALYSIS OF CEREBROSPINAL FLUID AND BRAIN PARENCHYMA IN A PATIENT WITH HYDRANENCEPHALY

Milan Radoš1, Branka Mucia- Pucia2, Ines Nikic1, Marina Ragu1, Valentina Galkowski1, Dora Mandic1, Darko Oreäkovi3, Marijan Klarica4

1 University of Zagreb, School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia 2 Special Hospital for Chronic Children Diseases, Gornja Bistra, Bistra, Croatia 3 Department of Molecular Biology, Rudjer Boskovic Institute, Zagreb, 4 University of Zagreb, School of Medicine, Department of Pharmacology and Croatian Institute for Brain Research, Zagreb, Croatia

Introduction: We present the first intracranial volumetric analysis of cerebrospinal fluid (CSF) and brain parenchyma in the supratentorial and infratentorial space of a 30-year-old female patient with hydranencephaly and macrocephaly.

Methods: 3T magnetic resonance imaging of the brain followed by manual segmentation of the brain parenchyma and CSF on T2 coronal brain sections was performed. Afterwards the volume of CSF and brain parenchyma was measured separately both for supratentorial and infratentorial space.

Results: The total volume of intracranial space in our patient was 3645.5 cm³. Inside the supratentorial space, CFS volume was 3375.2 cm³, while brain parenchyma volume was 80.3 cm³. Inside the infratentorial space, CSF volume was 101.3 cm³, and the brain parenchyma volume was 88.7 cm³. Inside the supratentorial space, severe malacias throughout almost the entire brain parenchyma, with no visible choroid plexus tissue residue, could be observed. Infratentorial structures of the brainstem and cerebellum were hypoplastic, but completely developed.

Conclusions: Since there are no choroid plexuses in the supratentorial space in our patient, and no obstruction can be found between dural sinuses and CSF, the development of hydrocephalus and macrocephaly is not possible to explain with classical CSF hypothesis based on secretion, unidirectional circulation and absorption. Origin and turnover of the enormous amount of intracranial CSF volume, which is at least tenfold higher than normal, and mechanisms of macroencephaly development could be explained with new hypothesis of CSF physiology recently published by our research team.

NEURORADIOLOGY

P099: THE MRI FINDINGS OF UNILATERAL DISPROPORTIONATELY ENLARGED SUBARACHNOID SPACE HYDROCEPHALUS IN A PATIENT WITH SECONDARY NORMAL PRESSURE HYDROCEPHALUS

Han-Lin Yen, Shih-Chung Tsai, Mei-Lin Sung

Tainan Municipal Hospital, Tainan, Taiwan Introduction: Normal-pressure hydrocephalus (NPH) is well known as a treatable syndrome in the elderly. The brain magnetic resonance imaging (MRI) finding of tight high-convexity and medial subarachnoid spaces, and enlarged Sylvian fissures with ventriculomegaly, defined as disproportionately enlarged subarachnoid space hydrocephalus (DESH), are worthwhile for the diagnosis of NPH. The feature of DESH in NPH is always in bilateral hemisphere. The Unilateral DESH had never been reported before in review of medical database.

Case report: A 71-year-old man was admitted to our hospital with disturbance of consciousness after a head injury. Craniotomy was performed for a left acute subdural hematoma. His consciousness recovered after the operation, but unsteady gait. After 4 months of rehabilitation, his condition deteriorated. The brain CT scans showed hydrocephalus. The MRI showed bilateral enlarged Sylvian fissures with ventriculomegaly but only left DESH was noted. The NPH was treated by programmable shunt. After shunting, the patient’s condition improved.

Discussion: The MRI features of DESH are useful for diagnosis of idiopathic NPH (iNPH). Our case was a secondary NPH due to head injury with left subdural hemorrhage. The hemorrhage may cause impairment of CSF absorption at the left arachnoid granulations and result in hydrocephalus. The reasons for DESH on CT or MRI in iNPH patients are not well understood. Based on classical CSF bulk flow theory, DESH may be a typical form of communicating hydrocephalus due to impairment of CSF absorption at the arachnoid granulations in the high-convexity region. The present case supported this viewpoint.

97 NEURORADIOLOGY

P100: COULD NEURONAVIGATION SIGNIFICANTLY IMPROVE THE RATE OF ACCURATE VENTRICULAR CATHETER LOCATION?

Marc Baroncini1, Cyril Capel1, Anthony Fichten1, Olivier Balédent2, Jean-Paul Lejeune1

1Department of Neurosurgery, Lille University Hospital, France 2BioFlow Image, Hospital University Center Nord, Amiens, France

Introduction: Placement of a ventriculoperitoneal shunt is the standard procedure for communicating chronic hydrocephalus in adults. Shunt survival may improve when ventricular catheters are correctly placed in the atrium or the frontal horn of the lateral ventricle (LV). Surgical techniques like neuronavigation for accurate catheter placement have recently been developed but not evaluated. Here we compare the position of the ventricular catheter using two surgical techniques: freehand or with neuronavigation.

Methods: 60 patients were operated in our two university hospitals by senior authors, targeting the atrium of the LV. The placement was considered to be correct (in the centre of the atrium), sub-optimal (intraventricular but in contact with ependymal) or extra-ventricular. A Fischer’s exact test was realized.

Results: Neuronavigation was used in 27 cases with 22 correct placements and 5 sub-optimal catheters. Freehand procedure was used in 33 patients with 28 catheters correctly placed and 5 sub-optimal. No catheter was in extra- ventricular position. There was no significant difference between the two surgical techniques (p=0.7422). No patient presented postoperative infection whatever the technique used.

Conclusions: It does not appear necessary to use systematically neuronavigation for the insertion of a ventricular catheter. Patients with chronic hydrocephalus are often elderly with large ventricles and careful installation in the operating room by a senior neurosurgeon often allows correct positioning of the ventricular catheter. Neuronavigation may be useful in specific cases with small ventricles but it is most often possible to do without, to shorten the duration of anaesthesia in these patients sometimes fragile.

NEURORADIOLOGY

P101: THE RELATIONSHIP BETWEEN BRAIN MATTER, CEREBROSPINAL FLUID AND COGNITIVE FUNCTIONS

Bader Chaarani, Jadwiga Zmudka, Joanna Woz, Marine Meerschman, Veronique Quaglino, Roger Bouzerar, Olivier Baledent

CHU AMIENS, Amiens, France

Introduction: The complete understanding of healthy aging remains a challenge. It is commonly admitted that, during aging, the brain matter volume decreases and the cognitive functions decrease in performance. Few studies on healthy volunteers examined the relationship between the cerebral morphology and performance on cognitive tests. This work aims to study the relationship between the age-related changes of the cerebrospinal fluid (CSF), white matter (WM) and grey matter (GM) volumes on one hand, and the cognitive functions alterations on the other.

Methods: 20 healthy elderly (mean age 74±8) underwent axial 3D T1 acquisition with a 3T MRI scanner. GM, WM, ventricular (CSFv) and subarachnoid (CSFs) volumes were calculated from 3D morphological images using FSL’s FAST segmentation tool. 13 subjects sustained neuropsychological tests intended to evaluate all of the cognitive functions.

Results: Mean±SD volumes (ml) were 437±120 for the GM, for 345±89 for the WM, 26 ± 11 mL for CSFv and 99 ± 24 mL for CSFs. Brain matter volume increased with aging, along with an increased CSF volume, as expected. A negative Pearson correlation was observed between the CSFv and GM volumes (R2=0.6, p<0.05) and between the CSFv and WM volumes (R2=0.8, p<0.05). Results showed a positive correlation between the WM volume and memory performance (R2=0.7, p<0.05), but not with executive functions. Surprisingly, the WM was positively correlated (R2=0.6, p<0.05) and the GM negatively correlated (R2=0.6, p<0.05) with the MMSE and the Mattis subtest.

Conclusions: In healthy subjects, the CSFv volume increase is more involved in the WM atrophy more than in the GM. The memory performance seems to depend more on the WM than the GM. Further studies on a larger population will be necessary to validate this hypothesis.

98 NEUROENDOSCOPY

P102: PREVIOUSLY SHUNTED OBSTRUCTIVE HYDROCEPHALUS THAT REQUIRED REPEATED ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV)

Eric Sankey, Ignacio Jusue-Torres, Jamie Robinson, Jan Wemmer, Jamie Hoffberger, Ari Blitz, Daniele Rigamonti

Department of Neurosurgery, Johns Hopkins Hospital, Baltimore, USA Introduction: CISS MRI aids clinicians in both the pre- and postoperative evaluation of CSF flow patterns and postoperative ventriculostomy patency. In this study, we evaluate the clinical and radiological outcomes of patients with previously shunted obstructive hydrocephalus that required repeated ETV followed with CISS MRI.

Methods: We retrospectively reviewed the clinical and radiographic data of 151 consecutive patients, treated between 2007 and 2013, with ETV for obstructive hydrocephalus. Ninety-six patients were excluded: 12 with communicating hydrocephalus and 84 with no previous shunting. Out of the 55 patients with previously shunted obstructive hydrocephalus, we included four patients (7%) that required repeated ETV. Median follow-up duration was 50 (48-55) months. Two (50%) patients were male and two (50%) female. Median age was 53 (4755)­ years at first ETV. Clinical outcome was reported as a percentage of improvement/worsening of the presenting symptoms. Continuous data was summarized using medians and interquartile ranges.

Results: Median time to repeated ETV was 59.5 (2588.5)­ months. At last followup­ (LFU), two (50%) of these patients improved, one (25%) remained unchanged and one (25%) worsened, both clinically and radiographically. Mean outcome score at LFU was +14.58% (­6.25 ­ 37.5%). However no statistical differences were found in clinical and radiological outcomes between patients that required repeated ETV and those who did not. All four patients had their first ETV after multiple shunt revisions.

Conclusions: Repeated ETV is a safe surgical option that may be indicated in patients that undergo ETV after multiple shunt revisions.

NEUROENDOSCOPY

P103: WHY IS ENDOSCOPIC THIRD VENTRICULOSTOMY (ETV) NOT AS SUCCESSFUL AS SHUNTING IN TREATMENT OF NORMAL PRESSURE HYDROCEPHALUS? PATHOPHYSIOLOGICAL CONSIDERATIONS Uwe Kehler

Department of Neurosurgery, Asklepios Klinik Altona, Hamburg, Germany

Background: The pathophysiological mechanism of normal pressure hydrocephalus (NPH) is the increased pulse pressure with its water hammer effect on brain tissue. The effect is boosted by the incompressible CSF in the ventricles, which cannot leave quick enough the ventricles with every pulse. This means the pulse pressure is hammering on the brain which is lying on a hard base. According to the hydrodynamic theory of NPH by Greitz, ETV should absorb the pulse pressure through opening the ventricular system towards the basal cisterns. But the clinical outcome of ETV in NPH compared to hydrocephalus shunting is inferior. Pathophysiological considerations should help to explain the difference between ETV and shunting.

Methods: The mechanisms of pulse pressure absorption realized by ETV and by hydrocephalus shunting with their efficacy are compared.

Results: ETV opens the ventricles to the subarachnoid space, facilitating the outflow of CSF. This CSF outflow may help to cut the peaks of the pulse pressure reducing the hammer effect; however, a quick outflow with every pulse is physical limited by the inertness of CSF. This reduces the effect of absorbing the pulse pressure.

Shunting has two mechanisms, which helps to reduce the effect of the water hammer: the first is similar to ETV with facilitating the CSF outflow of the ventricles via the shunt. The second and probably even more important mechanism is the more or less constant drainage of CSF leading to a compressible (“soft”) ventricular content: the hard base of the brain is changed to a soft pad – absorbing better the pulse pressure.

Conclusions: These considerations can convincingly explain a positive clinical effect of ETV and shunting, but can also explain the superior effect of shunting on symptoms relieve. From this point of view every insufficient clinical improvement after ETV should be evaluated for shunting.

99 NEUROENDOSCOPY

P104: NEUROENDOSCOPES – IS BIGGER ALWAYS BETTER?

Bassel Zebian1, Christos Chamilos1, Vita Stagno1, Chris Chandler2, Conor Mallucci1, Benedetta Pettorini1, Sanj Bassi2, Chris Parks1

1Alder Hey Children’s NHS Foundation Trust, Liverpool, United Kingdom 2King’s College Hospital NHS Foundation Trust, London, United Kingdom Background: Neuroendoscopy has increased in popularity over recent years. The trend has been for larger scopes that allow the use of multiple instruments and provide improved visualisation and versatility. These scopes have undoubtedly increased the armamentarium of the endoscopic neurosurgeon. We present our use of the somewhat less popular disposable small diameter neuroendoscopes in a patient with complex hydrocephalus and an encysted 4th ventricle with a short video demonstrating its application.

Case Report: In the case described, the small diameter neuroendoscope provided safer stent placement across the aqueduct and successful treatment of the encysted 4th ventricle and hydrocephalus. In other cases, similar endoscopes have provided us with added visualisation in intracranial spaces that would have been out of reach of their larger counterparts and / or the microscope. These endoscopes due to their small overall size and their shape also lend themselves to endoscopic assisted surgery.

Conclusions: Small diameter neuroendoscopes are underutilised. The inferior quality of the image they provide and the lack of working channels are largely to blame. In select cases, however, they allow visualisation when it would have been otherwise difficult to do so, and certainly in the case presented they provided us with a novel technique for the treatment of an encysted 4th ventricle.

NEUROENDOSCOPY

P105: THE RESULTS OF ENDOSCOPIC THIRD VENTRICULOSTOMY AND AQUEDUCTAL STENTING AT THE ROYAL HOBART HOSPITAL, TASMANIA AUSTRALIA

Katherine Poulgrain, Asim Mujic, Andrew Hunn, Albert Erasmus, Arvind Dubey, Jens Peters-Willke, Andrew Gauden, Arthur Ellice-Flint

Royal Hobart Hospital, Tasmania, Australia Background: The indications for endoscopic third ventriculostomy (ETV) as a treatment modality for hydrocephalus remain unclear. Similarly, indications for aqueductal stenting (AS) are undefined. Several reports advocate the use of stenting of the aqueduct over aqueductoplasty due to the frequent occurrence of re-stenosis.

Methods: A retrospective audit of all ETV and AS cases was conducted at the Royal Hobart Hospital from January 2006 to June 2014.

Results: The outcomes from 32 cases of ETV and 5 cases of AS demonstrated a success rate of 69% (22 cases) for ETV, the majority (72%) of which comprised cases of obstructive hydrocephalus secondary to tectal plate lesions and aqueductal stenosis of unknown cause. ETV as a treatment for normal pressure hydrocephalus (4 cases) had mixed results, with two cases requiring subsequent ventriculoperitoneal shunting (VPS). Our experiences demonstrated ETV was unsuccessful as a treatment for hydrocephalus secondary to germinoma. We hypothesis this is due to the highly infiltrative nature of the underlying lesion. All cases of AS had patent cerebral aqueducts at follow up. One patient experienced a transient sixth nerve palsy following AS, highlighting the importance of correct implant placement given the sensitive nature of the periaqueductal grey matter.

Conclusions: Aqueductal stenting is not without risk of neurological impairment related to the presence of a stent in a tight aqueduct. It is worth considering this when placing stents into the lumen of the aqueduct so as to avoid compression of the periaqueductal grey matter and the neurological impairments that may develop. Aqueductal stenting and endoscopic third ventriculostomy can be successfully employed as treatment options for certain cases of hydrocephalus. Their long term results and specific indications are however yet to be defined.

100 NEUROENDOSCOPY

P106: EFFICACY OF ENDOSCOPIC SURGERIES FOR OBSTRUCTIVE HYDROCEPHALUS ASSOCIATED WITH TUBERCULOUS MENINGITIS: A CASE REPORT

Shigeki Nakano, Hisayuki Murai, Yue Gao, Norio Ishiwatari, Naokatsu Saeki

Department of Neurological Surgery Chiba University Graduate School of Medicine, Chiba, Japan Background: Tuberculous meningitis is difficult to treat and often complicated with hydrocephalus. Although ventriculoperitoneal (VP) shunt is effective for these cases, the hydrocephalus sometimes recurs because of ventricle wall adhesion, which occasionally needs multiple shunts. We report a case of recurrent obstructive tuberculous hydrocephalus after VP shunt successfully treated with endoscopic dissection of ventricle wall adhesion using balloon catheter and septostomy.

Case Report: A17-year-old woman presented with a slight fever, headache and double vision was diagnosed tuberculous meningitis. Antituberculous chemotherapy and dexamethasone was started immediately. Communicating hydrocephalus appeared one month before admission to our hospital and VP shunt with right occipital horn puncture was performed. After that, shunt malfunction with left ventricular enlargement and right slit ventricle occured, so she underwent septostomy 53 days after VP shunt with flexible neuroendoscope through left anterior horn.

The hydrocephalus improved temporarily, but seven months after first septostomy, left temporal and occipital horn enlarged again and she felt drowsy. We performed second endoscopic septostomy following left occipital horn puncture. The body of left lateral ventricle was obstructed because of ventricle wall adhesion. Using a balloon catheter, we dissected the adhesion and performed septostomy and biopsy of diffusion high lesion on MRI. To prevent the recurrence of obstructive hydrocephalus, we placed a stent catheter with additional multiple side holes and Ommaya reservoir in left anterior horn through the stoma. After the surgery, her symptom and hydrocephalus improved immediately.

Conclusion: Endoscopic surgery can prevent additional shunt or lobectomy for the treatment of obstructive hydrocephalus after VP shunt.

IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

P107: VENOUS SINUS STENTING IN IDIOPATHIC INTRACRANIAL HYPERTENSION: A TERTIARY CENTRE EXPERIENCE

Chris Kellet1, Ahmed Toma1, Fergus Robertson2, Simon Thompson1, Samir Matloob1, Samira Akmal1, Lewis Thorne1, Laurence Watkins1

1Department of Neurosurgery, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom 2Department of Neuroradiology, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom

Background: Idiopathic intracranial hypertension (IIH) remains enigmatic and management challenging. Recent experience has identified a subset of patients, with elevated venous pressure secondary to venous sinus stenosis (VSS), amenable to stenting. Clinical and angiographic data are examined pre and post treatment. Cases of particular interest are presented, ICP waveform analysis performed and the economic impact of surgical and endovascular therapy is discussed.

Method: A retrospective review of all eighteen stented IIH patients from 2010 - 2014 at the authors’ institute. All patients were female with a mean age of 35 years. Seventeen patients (94%) had visual loss in addition to headache. Mean time from diagnosis to stenting was 3.4 years. Eight patients (44%) underwent multiple CSF diversion procedures and one patient optic nerve sheath fenestration. Venographic evidence of VSS and trans-stenotic pressure gradients were acquired in all patients. ICP wave-form analysis was performed in four patients. Ten patients (56%) underwent follow-up venography. Mean clinical and radiological follow-up was twenty and twelve months respectively.

Results: Endovascular therapy was technically possible in all patients. Twelve patients (67%) underwent stenting for stenosis of a dominant right transverse sinus, two patients for transverse-sigmoid junction stenosis and two patients had bilateral stenosis. 21 stents were deployed with improvement in pressure gradient in all patients. Fifteen patients (83%) experienced significant improvement in headache, visual symptoms and medication reduction. One patient had an intra- procedural haemorrhage without sequelae. In-stent stenosis was identified in two patients (11%) at three days and 21 months respectively. Both patients underwent further endovascular treatment with good outcome. Three patients remain shunt dependent despite patent stents.

Conclusions: Endovascular treatment is evolving. Venous imaging is prudent during the investigation of IIH. Where VSS is demonstrated, stenting should be considered early. Endovascular therapy is efficacious, associated with low morbidity, good outcome and is cost effective.

101 IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP)

P108: MANAGEMENT OF HYDROCEPHALUS AND IDIOPATHIC INTRACRANIAL HYPERTENSION IN PREGNANCY

Victoria Wykes1, Ahmed Toma1, Simon Thompson1, George Prezerakos1, Mustafa Ali2, Fergus Robertson2, Joan Grieve1, Laurence Watkins1

1Department of Neurosurgery, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom 2Department of Neuroradiology, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom

Background: Normal intra-abdominal pressure (IAP) ranges from 0-6.5 mmHg1. Intra-abdominal hypertension is defined as IAP greater than 12mmHg2 and can occur in a range of conditions including trauma, pregnancy and obesity. At term the IAP can range from 2-29 mmHg (median 22 mmHg)3, with 25% of women having an IAP >12mmHg1. In this study we examine the last 4 years experience of pregnant women with, or requiring, a shunt presenting to the National Hospital of Neurology and Neurosurgery.

Methods: Retrospective case series from June 2010 - June 2014 identifying all pregnant patients presenting with or requiring a CSF diversion device during gestation.

Results: Of 7 female patients (mean age 31 years), 57% had Idiopathic Intracranial Hypertension (IIH), 2 had aqueduct stenosis and 1 had Chiari 1 malformation. 6 patients had CSF shunts in situ pre pregnancy (2 ventricular-peritoneal shunt, 2 ventricular-pleural shunts, 2 lumbar-peritoneal shunts). 4 ladies presented at a mean of 25 weeks gestation with signs or symptoms of raised intracranial pressure. 1 patient had a lumbar-pleural programmable shunt inserted at 22 weeks gestation, while 3 patients required lowering of the adjustable valve setting. 1 patient experienced low-pressure symptoms post partum and the 3 patients who had their valves changed during pregnancy had their shunt valves re-optimized post partum. The 2 patients with ventricular-pleural shunts were reviewed during pregnancy but had no neurological symptoms. Limited T2 axial Magnetic Resonance Imaging at the level of the Foramen of Monroe were useful in assessing ventricular size.

Conclusions: We suggest that in women of child-bearing age: adjustable valves should be considered in ventriculo-peritoneal shunts; extra-peritoneal placement of distal catheter should be considered. Limited T2 axial Magnetic Resonance Imaging at the level of the Foramen of Monro may be useful to assess ventricular size.

IDIOPATHIC INTRACRANIAL HYPERTENSION (IIH) / VISUAL IMPAIRMENT DUE TO INTRACRANIAL PRESSURE (VIIP) P109: FEASIBILITY OF OPHTHALMIC ARTERY BLOOD FLOW QUANTIFICATION IN HYDROCEPHALUS PATIENTS

Veronique Promelle, Cyrille Capel, Roger Bouzerar, Joel Daouk, Solange Milazzo, Catherine Gondry-Jouet, Olivier Baledent

University Hospital, Amiens, France

Introduction: Hydrocephalus as intracranial hypertension patients can develop papilledema. The aim of this study was to measure ophthalmic artery (OA) blood flow by mean of phase contrast magnetic resonance imaging (MRI) in hydrocephalus patients and controls.

Methods: A phase contrast MRI with cardiac synchronisation was performed for 5 eyes of 3 hydrocephalus patients with aqueductal stenosis and 5 eyes of 4 controls on a 3 Tesla MRI, in order to measure OA blood flow and ipsilateral internal carotid blood flow. A measurement plan was placed perpendicularly to the orbital part of the OA, with a field of view of 120x120 mm, a matrix of 256x128 (reconstructed 256), a slice thickness of 5 mm, an encoding velocity of 80 cm/s and 32 phases per cardiac cycle. The duration of acquisition was less than 2 minutes. Segmentation of OA was obtained by a dedicated software to calculate blood flow curves.

Results: The mean OA blood flow was 14.7 ± 7.1 mL/min in patients and 14.7 ±2.4 mL/min in controls, with a systolic flow of 38.5 ± 20 (vs 34.3 ± 3.6 in controls) and a diastolic flow of 6.5 ± 4.5 mL/min (vs 3.9 ± 2.3). The mean OA flow rate was 7 ±2 % of the mean internal carotid flow rate in patients and in controls. The systolic OA flow rate was 10 ± 4% of the systolic internal carotid flow rate in patients vs 9 ± 3 % in controls.

Conclusion: These preliminary results on a few patients didn’t show any significant differences in OA blood flow between hydrocephalus patients and controls. Nevertheless, phase contrast MRI proved to be a possible non-invasive way to explore OA hydrodynamics (quantitative values and flow wave).This could be of interest in exploration of visual impairment accompanying intracranial pressure alterations following low-gravity space journeys.

102 PAEDIATRIC HYDROCEPHLAUS

P110: WALTER DANDY: OPERATIVE EXPERIENCE WITH HYDROCEPHALUS AT THE JOHNS HOPKINS HOSPITAL

Ari Blitz, David Solomon, Daniele Rigamonti

Neuroradiology, Johns Hopkins Hospital, Baltimore, MD USA

Background: Walter Dandy was one of the preeminent neurosurgeons of the twentieth century and a pioneer of early neuroradiologic and operative approaches to patients with hydrocephalus. Dandy’s papers, housed in the Alan Mason Chesney archives of the Johns Hopkins University, include surgical case logs with a brief description of each case.

Methods: IRB approved retrospective evaluation of the papers of Walter Dandy pertaining to hydrocephalus. The number of operations per year and type of operation performed were recorded as well as Dandy’s classification of the etiology of hydrocephalus.

Results: Walter Dandy performed his first operation on a patient with hydrocephalus in 1915 and his last in 1946. Cases of hydrocephalus attributed to brain tumors were recorded in a separate log with only 9 cases classified in this manner. Including cases of hydrocephalus associated with a mass. Dr. Dandy brought patients to the operating room 381 times during his career. Cases were classified as communicating, non-communicating or on the basis of site of obstruction of CSF flow (e.g. stenosis of the cerebral aqueduct, “diffuse scar of the foramen of Magendie”). Dandy first performed choroid plexus excision for treatment of hydrocephalus in 1916. In 1918 he records creation of a “new foramen of Magendie” for the first time. The first “removal of the floor of the 3rd ventricle” was performed in 1920. The final operation for hydrocephalus of his career was a choroid plexectomy in 1946.

Conclusions: Walter Dandy’s early clinical experiences were critical in shaping our field. Reviewing the variety of case material and evolution of knowledge during the span of his career may provide insight into how far the diagnosis and treatment of hydrocephalus has come and how far remains to be travelled.

PEDIATRIC HYDROCEPHALUS

P111: NAVIGATED ENDOSCOPY FOR CYST FENESTRATION IN THE TREATMENT OF MULTILOCULATED HYDROCEPHALUS IN CHILDREN

Segrei Kim1, Hanne Wakabayashi2, German Letyagin1, Vasiliy Danilin1, Steen Hasselbalch1

1Federal Center of Neurosurgery, Novosibirsk, Russia 2Danish Dementia Research Centre, Copenhagen, Denmark Introduction: Patients with different variants of multiloculated hydrocephalus are the most complex patient group faced by neurosurgeons. Standard shunt implantation does not bring positive results. Using endoscopic technique improves the results of treatment of such patients, but neurosurgeons often have difficulty in planning and intraoperative orientation in conditions of impaired anatomy and lack of landmarks. Application of frameless navigation during endoscopic interventions can significantly ease the task of the surgeon and improve the efficiency of operations.

Methods: 8 patients with various forms of multiloculated hydrocephalus were treated in our hospital from March 2013 to June 2014. Preoperatively the optimal entry point for fenestration a few cysts was determined on the basis of MR data. During surgery rigid endoscope was registered in neuronavigation system for making the connection between a separated ventricles and cysts. The final stage of the operation was to conduct a stent through the working channel of the endoscope for implantation of a shunt.

Results: 9 navigated endoscopic procedures were performed in 8 children. Number of compartments interconnected by an operation ranged from 3 to 5. Seven interventions performed simultaneously with the shunt implantation. The follow-up period ranged from 9 to 15 months. All the children achieved clinical improvement as a result of the operation. Follow-up included clinical examination and evaluation of MRI. Additional surgery was necessary in 2 patients: one in 5 months, the second in 1 year after endoscopic intervention.

Conclusions: Application of navigated neuroendoscopy makes this kind of operations the most efficient and safe for the patient. The aim of operation is to drain maximum possible number of cavities using minimal amounts of the proximal catheters and shunting systems, and sometimes even prevent shunting

103 PEDIATRIC HYDROCEPHALUS

P112: MANAGEMENT AND OUTCOME OF INFANTILE HYDROCEPHALUS IN A TERTIARY HEALTH INSTITUTION OF A DEVELOPING COUNTRY

Ayodeji Yusuf1, Nurudeen Adeleke1, Oluwaseun Akanbi1,2, Olalekan Ajiboye1

University of Ilorin and University of Ilorin Teaching Hospital. Ilorin, Nigeria Danish Dementia Research Centre, Copenhagen, Denmark Introduction: Hydrocephalus is a leading cause of disability among children worldwide. Outcome depends on morphology and whether insult is pre or post-natal. There has been improvement in morbidity in developed countries due to improved surgical care. Paucity of trained personnel impact negatively on care and outcome of infants with hydrocephalus in many low income countries resulting poorer outcome. We conducted an audit of patients with Hydrocephalus managed in our institution to determine common aetiology and outcome.

Methods: This is a retrospective study of infants (<12months) with hydrocephalus managed in our neurosurgical division over three years. Information on demography, aetiology, treatment modality and outcome of care were retrieved from the patients’ case file using a predesigned proforma.

Results: A total of 58 infants (33 male; 25 female) with hydrocephalus were studied. Majority, 49 (64.5%), were below the age of 6 months. Most hydrocephalus (40, 69%) were congenital with 14 (35 %) occurring in association with myelomeningocele and 8 patients confirmed with aqueductal stenosis. Intraventricular haemorrhage (10) and meningitis (7) were the commonest acquired causes. Eighteen (31%) infants were treated without any confirmed aetiology of their hydrocephalus. Ventriculoperitoneal shunts insertion (53, 91%) was the commonest treatment modality. Three patients with IVH had ventriculo-subgaleal shunt insertion as temporising measure and 2 patients had endoscopic third ventriculostomy (ETV) a newly introduced modality in the centre. Twenty three patients (40%) developed complications during the course of follow up with shunt infections (7, 12%), shunt obstruction (5,9%) and shunt over-drainage (2, 3%) respectively. Two patients died while still on admission giving a mortality of 3.4%.

Conclusion: Morbidity from hydrocephalus was high following predominately shunt insertion. There is need to improve surgical intervention in the form of ETV in suitable patients and ensure aetiological diagnosis for majority of the infants with hydrocephalus.

PAEDIATRIC HYDROCEPHALUS

P113: DISCURSIVE NEUROLINGUISTICS AND LITERACY IN THE SOCIAL INCLUSION OF CHILDREN WITH NEUROLOGICAL AFFECTION DEFINED AS HYDROCEPHALUS

Dionéia Monte-Serrat1, Maria Irma Coudry1, Leda Tfouni2, Sérgio Mascarenhas3

1IEL-UNICAMP, Campinas, Brazil 2FFCLRP-USP, Ribeirao Preto, Brazil 3IFQSC-USP, Sao Carlos, Brazil

Background: The theoretical and methodological fundamentals of Discursive Neurolinguistics are associated, in this study, with the Literacy theory aiming to investigate subjectivity marks in the oral and written productions of children with hydrocephalus and to promote their social inclusion. Hydrocephalus results from the disruption of the cephalorachidian fluid balance, and it is the cause of 60% of the total number of pediatric neurosurgical procedures in the Ribeirão Preto School of Medicine University Hospital – USP. Among the sequelae presented by patients after treatment, the most worrisome is neuropsychomotor impairment.

Methods: Such condition places children in a setting of social marginalization which we intend to change by correlating theory and concepts with methodological practices in order to observe how hydrocephalic children embody the discursive practice of language by marking their subjectivity and also observe how the protective function of language occurs in these children. We ultimately aim at developing evaluation strategies adapted to the difficulties of language functioning in children with this affection that are not based on abstraction or on the performance of an idealized object, since children with hydrocephalus do not show certain resources for meaning production and interpretation. Hence, with supervision by Coudry, we intend to associate Discursive Neurolinguistics with the Literacy theory so that this study can bring children with hydrocephalus the opportunity to develop successful linguistic interaction by acting on the structuration of these children’s subjectivity.

Conclusions: The collaboration from the study group coordinated by Dr. Sérgio Mascarenhas, in association with the Ribeirão Preto School of Medicine University Hospital - USP, has provided a multi-disciplinarity character to the study which has enhanced the possibilities to intervene in psychomotor alterations related to language use. Our scope is that of providing these children with a perspective of escaping an isolation that is not only linguistic, but also emotional, intellectual and cultural.

104 NEUROENDOSCOPY

P114: OBSTRUCTED SHUNT UPPER END REMOVAL BY AGIOPLASTIC BALLOON WITH VENTROSCOPIC GUIDANCE Abbas Alnaji

Al-Sader Medical City, Najaf, Iraq

Background: Shunt upper end catheter may be obstructed by choroid plexus when the tip is in the ventricular occipital horn. If the upper end is pulled out for replacement the anchoring choroid plexus vessels will be avulsed and bleed.

Case Series: Balloons used in percutaneous coronary angioplastic catheters (Cordis 2.0) can be folded and introduced through the upper end orifice and lumen up to the fenestrated obstructed end of the proximal catheter. When the balloon is inflated by normal saline for the suitable pressure, the balloon acts to dilate and separate the arachnoid fibres away from the fenestrated tip gently. By repeat this process of inflation and deflation of the balloon with advancement of the balloon gradually, the whole upper end is released by relaxation of the wrapping fibres. This includes the exit of arachnoid fibres entered the lumen through the holes by the squeezing action of the balloon.

Conclusions: The outer end of the shunt catheter should be fixed to prevent slipping into the ventricle during balloon advancement. The Ventriculoscope is used to visualize what is happening outside the shunt tip and to give the OK for the tip complete release. 10 cases with obstructed upper ends were replaced by such technique without bleeding.

SHUNT HARDWARE DESIGN

P115: UNDERSTANDING OVERDRAINAGE IN PATIENTS WITH SLIT-VENTRICLES

Christoph Miethke

Christoph Miethke GmbH & Co. KG, Germany Introduction: Slit-like ventricles are a common problem in patients having been shunted with DP-valves during early childhood. Not-seldom these patients are facing severe clinical problems many years after being shunted, which are sometimes hardly treatable. The understanding of the background of these difficulties might offer new proposals to solve them.

Methods: A computer-controlled apparatus has been developed including a model of the ventricles, the CSF-production rate, the peritoneal cavity and a connecting shunt-system, which allows the investigation of different valve types and parameters like ventricle compliance, posture depending changes or different flow rates. Various valve types are tested especially to understand their performance in cases of slit-like ventricles (low compliance).

Results: There is a significant dependency on time and compliance if a flow-reducing device is tested. Generally a rapid reaction can be observed for any valve type if a ventricle with a low compliance is tested.

Conclusions: The results demonstrate that even very small volume changes due to CSF-flow throughout a shunt are followed by a significant rapid pressure change within slit-ventricles. This might explain why it seems to be a remaining challenge to achieve a very good clinical outcome in this patient group. A switch, which opens the shunt depending on time, could promise a solution.

105 SHUNT HARDWARE DESIGN

P116: DEVELOPMENT OF A DUAL SENSOR PLATFORM FOR MONITORING HYDROCEPHALUS SHUNTS

Lawrence Yu, Brian Kim, Curtis Lee, Ellis Meng

University of Southern California, Los Angeles, USA

Introduction: Currently there are no practical methods to definitively diagnose obstruction failure of ventricular shunts without surgical intervention. Monitoring shunt patency can prevent harmful complications during hydrocephalus management. We developed a simple dual sensor platform that can track intracranial pressure and obstruction of shunt drainage ports via electrochemical impedance. Methods: The platform consists of a pressure and patency sensor microfabricated on a flexible Parylene C polymer substrate (20 μm thick) with thin film platinum electrodes. To detect pressure, a microbubble is electrolytically generated and instantaneously responds to pressure changes which are measured as changes in electrochemical impedance between a pair of electrodes situated on either side of the bubble. For patency measurement, electrodes are situated internal and external to the catheter such the drainage ports establish an ionic conduction path. Disturbances in the fluidic path (i.e. blockage) perturb the conductive pathway and trigger an increase in the measured electrochemical impedance.

Results: The sensor platform was integrated into a luer-lock compatible module for connection to a commercial external ventricular drain catheter system. Pressure variations in the range of 0-300 mmHg were transduced with a sensitivity of -93Ω/mmHg over a time span of more than 10 minutes. Patency results indicated that the impedance varied with the percent blockage of the catheter (26% impedance increase for 87% blockage). Real-time tracking of dynamic blockage simulated by sheathing/unsheathing the catheter was also demonstrated.

Conclusions: We developed pressure and patency sensors using polymer microfabrication technology that enable monitoring of shunt status through the use of electrochemical impedance transduction methods. These sensors can be modified for integration with current shunts. Shunts with embedded sensors can achieve more accurate and timely diagnosis of failure and improve patient outcomes.

Sunday 7th September 8.00 - 18.00

NORMAL PRESSURE HYDROCEPHALUS

P117: IS VENTRICULOMEGALY A MANDATORY CONDITION TO DEVELOP THE SIGNS AND SYMPTOMS OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS? Kiyoshi Takagi

Chiba-Kashiwa Tanaka Hospital, Kashiwa, Japan

Background: Ventriculomegaly has been a mandatory condition for NPH since Adams et al. However, it has not been demonstrated whether the patients with the symptoms of NPH without ventriculomegaly don’t improve by the shunt surgery. Guidelines for iNPH define ventriculomegaly as Evans index (EI) greater than 0.3. I have treated iNPH by VA shunt since 2004. This study aims to investigate whether ventriculomegaly is a mandatory condition for iNPH.

Methods: I have treated 348 cases with symptoms of iNPH by VA shunt with the follow-up period over 3 months. EI was greater than 0.3 (Group A) in 249 cases and less than 0.3 (Group B) in 99 cases. The outcome at 3 months after the surgery was evaluated in 4 categories; E (Excellent; improvement of mRS or improvement of MMSE over 3), G (Good; no improvement of mRS but decreased caregiver’s burden), F (Fair; no or slight improvement), and P (Poor; worsen). The outcomes were compared between two groups. Statistical analysis was performed by Student’s t-test or Chi-square test. Statistically significant level was set at p less than 0.05.

Results: The mean ages and the number of male and female for Group A and B were 77.9 +/- 6.8 yo and 77.8 +/- 6.3 yo (p = 0.9402), 144:105 (male:female) and 42:57 (p = 0.009) respectively. The number of outcome of E, G, F, P for Group A and B were 179, 39, 26, 5 and 61, 18, 18, 2 respectively without significant difference (p = 0.1939).

Conclusion: This study clearly demonstrated that the ventriculomemaly defined by EI is not a mandatory condition for iNPH. Unexpectedly, sex difference between the 2 group was observed. The proposal by Adams et al. may miss lead the diagnosis of dementia, gait disturbance, and urinary incontinence in the elderly.

106 NORMAL PRESSURE HYDROCEPHALUS

P118: CONCEPTUAL CHANGE OF INITIAL SETTING PRESSURE OF CHPV AND WITH SG FOR INPH Masaaki Hashimoto, Takuya Watanabe, Tunehito Nakao

Noto General Hospital, Nanao, Japan

Background: In our hospital, we shunted routinely by Codman Hakim programmable valve (CHPV) for idiopathic normal pressure hydrocephalus (iNPH) patients from 1994. During 20 years (1994 ~ 2013), 206 iNPH patients were shunted and we examined the conceptual change of strategic initial setting pressure (ISP).

Methods: We divided these years into 4 phases along to the empirical conceptual change of ISP of CHPV.

Results: 1st phase: 1994 ~ 2000 (46 cases, ISP: 90 ± 14.8 mmH2O). In this phase, we felt the good shunting effect for iNPH by CHPV. But, 3 over-drainage (OD) problems with surgical intervention (SI) (chronic subdural hematoma and acute subdural hematoma) were observed.

2nd phase: 2000 ~ 2003 (46 cases, ISP 117 ± 32 mmH2O).We gradually set higher ISP for the resolution of over-drainage (OD) problems. In this phase, nevertheless, we experienced 8 OD-SI’s in many years later after shunting operation.

3rd phase: 2003~ 2006 (43 cases, ISP 116 ± 29 mmH2O).We introduced routinely CHPV with SiphonGuard (SG) system for shunt system from 2003. We felt more safety and easy post operative management than early phase’s, and relative good efficacy of this system.

4th phase: 2006 ~ 2013 (63 cases, ISP 148 ± 24 mmH2O). In each shunting route’s (VP or LP), we used SG system with more higher ISP. After shunting operation, we gradually low down the setting pressure.

About 12 years after 2003, we almost controlled OD problems and we did not experienced OD-SI. In spite of higher setting with SG system, good operative outcome was observed.

Conclusions: During 20 years, we gradually changed our empirical strategy for ISP and post-operative management of iNPH patients. Shunting operation by CHPV with SG for iNPH patients is a standard option in our hospital after 2003.

NORMAL PRESSURE HYDROCEPHALUS

P119: VENTRICULO-SCLERATHEROMA: IS ONE OF THE ETIOLOGY OF NORMAL PRESSURE HYDROCEPHALUS? Qing Xiao, Guo-qiang Chen, Jia-ping Zheng

Aviation General Hospital of China Medical University, Beijing, China

Background: To demonstrate the pathological manifestation of the ventricle in normal pressure hydrocephalus.

Methods: 8 cases of normal pressure hydrocephalus were treated with endoscopic third ventriculostomy from June 2007 to July 2013. The whole ventricular system was explored and observed with flexible endoscope.

Results: Among 8 cases, ventriculo-scleratheroma presented in 5 cases. The clinical symptoms were improved in different degree in 6 cases after endoscopic third ventriculostomy during a postoperative 6 months follow up.

Conclusion: Ventriculo-scleratheroma maybe one of the etiologies of normal pressure hydrocephalus.

107 NORMAL PRESSURE HYDROCEPHALUS

P120: COMPUTERIZED GAIT ANALYSIS WITH INERTIAL SENSOR AS AN IMPORTANT SUPPORTING TOOL FOR CORRECT AND EARLY DIAGNOSIS IN PATIENTS WITH SUSPECT IDIOPATHIC NORMAL-PRESSURE HYDROCEPHALUS

Marco Gelmini, Pier Paolo Panciani, Karol Migliorati, Marco Fontanella

Department of Neuroscience, Division of Neurosurgery, University of Brescia, Brescia, Italy Background: Gait disturbance is assessed as the most significant criterion for the diagnosis of idiopathic Normal-Pressure Hydrocephalus (iNPH). The march is described as glue-footed, ataxic and magnetic. However, it has not yet been identified a typical pattern based on objective parameters. The march disturbances may be attributed to other neurodegenerative diseases and this may lead to fail the diagnosis. The aim of this study was to work out a pathognomonic walking pattern for iNPH using an innovative computerized system. Moreover, we evaluated the gait parameters more susceptible to variation in response to CSF tapping in order to achieve an innovative and easily applicable tool for iNPH diagnosis.

Methods: We collected the gait parameters of all the patients with suspect iNPH that underwent CSF tapping in our Department from May 2012 to May 2014. We used an innovative system (BTS G-WALK®) that through an inertial sensor fixed on a belt allowed to determine multiple gait parameters as speed, cadence, step length and height. We elaborated the results considering only the gait analysis of the patients with confirmed diagnosis after ventricular shunt. Their pre- operative parameters were compared to standard range normalized for age, height and weight of the patients. Moreover, we compared their analysis before and after CSF tapping.

Results: We enrolled 65 patients with suspect iNPH, but we considered only 38 of them that showed clinical improvement after shunt. Speed, cadence, stride length, % stride length/height, gait cycle duration and double support duration were the most relevant parameters affected in iNPH patients. On the other hand, the most responsive parameters to CSF tapping were speed, stride length, % length/height and gait cycle duration.

Conclusions: The inertial sensor system allows to detect typical gait features of iNPH patients. It could be a useful tool to improve the challenging and often doubtful diagnosis of iNPH.

NORMAL PRESSURE HYDROCEPHALUS

P121: SHUNTING OF THE OVER 80S IN NORMAL PRESSURE HYDROCEPHALUS.

Simon Thompson, James Shand Smith, Akbar Khan, Ahmed Toma, Neil Kitchen, Laurence Watkins

Department of Neurosurgery, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom Background: Primary or Idiopathic normal pressure hydrocephalus is predominantly a disease of the elderly. By its nature many of those who present to clinic are in advanced old age with multiple co-morbidities. We present the clinical outcomes and complication rates of patients, over the age of 80 at the time of operation from the past 8 years in a single institution.

Methods: Retrospective analysis of clinical records of all patients over the age of 80 who presented at our institution between 2006 and 2013. Results were analysed for; co-morbidities, pre-op walk and neuropsychology test results, immediate complications and delayed complications, 10m walk test and neuro-psychology outcomes.

Results: 30 patients over the age of 80 (17 male, 13 female). Mean age at the time of shunt insertion was 83.5 years (range 80-92). Mean follow up was 21 months excluding one patient refusing to attend clinic. No patients developed infection, immediate sub-dural or extended length of stay. There were no peri-operative or anaesthetic complications. No patients required revision. 2 patients went on to develop delayed subdural haematoma, both of which were associated with trauma. 22 patients (73%) improved in their walk test. 19 (63%) patients / families reported symptomatic improvement in their cognition and memory of which 9 (30% of total) had a supporting formal neuro-psychology.

Conclusions: Our data supports the assertion that, with proper patient selection, shunting of the over 80s with iNPH is a safe and effective procedure.

108 NORMAL PRESSURE HYDROCEPHALUS

P122: INCREASED γ- SECRETASE ACTIVITY IN IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS PATIENTS WITH Β-AMYLOID PATHOLOGY

Tiina Laiterä, Timo Sarajärvi, Annakaisa Haapasalo, Laksman Puli, Juha Jääskeläinen, Hilkka Soininen, Ville Leinonen, Mikko Hiltunen

Institute of Clinical Medicine - Neurosurgery, University of Eastern Finland / Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland Introduction: The potential similarity between the brain pathology of idiopathic normal pressure hydrocephalus (iNPH) and Alzheimer disease (AD) is intriguing and thus further studies focusing on the underlying molecular mechanisms may offer valuable information for differential diagnostics and the development of treatments for iNPH.

Methods: We investigated γ ²- and γ ³-secretase activities in relation to amyloid- β² (Aβ²) pathology in the brain tissue samples collected from iNPH and AD patients. γ ²- and γ ³-secretase activities were measured from the frontal cortical biopsies of 26 patients with suspected iNPH and from the inferior temporal cortex of 74 AD patients.

Results: In iNPH samples with detectable A β² plaques, γ³-secretase activity was significantly increased (~1.6-fold) when compared to iNPH samples without Aβ² plaques (p = 0.009). In the AD samples, statistically significant differences in the γ³-secretase activity were not observed with respect to disease severity (mild, moderate and severe AD according to neurofibrillary pathology). Conversely, γ ²-secretase activity was unaltered in iNPH samples with or without A β² plaques, while it was significantly increased in relation to disease severity in the AD patients.

Conclusions: These results show for the first time increased γ ³-secretase but not γ²-secretase activity in the biopsy samples from the frontal cortex of iNPH patients with AD-like Aβ² pathology. Conversely, the opposite was observed in these secretase activities in AD patients with respect to neurofibrillary pathology. Despite the resemblances in the A β² pathology, iNPH and AD patients appear to have marked differences in the cellular mechanisms responsible for the production of Aβ².

NORMAL PRESSURE HYDROCEPHALUS

P123: INFLUENCE OF AΒ DEPOSITION ON CLINICAL MANIFESTATIONS OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Masahiko Bundo, Takashi Kato, Akinori Nakamura, Kengo Ito

National Centre for Geriatrics and Gerontology, Obu, Japan Background: It is known that idiopathic normal pressure hydrocephalus (iNPH) can be comorbid with Alzheimer disease (AD). Previous studies, probing amyloid (Aβ²) deposition by cortical biopsy during a ventriculo-peritoneal shunt, have shown that Aβ² deposition was found in 40~45 % of iNPH patients. However, influence of AD pathology on clinical manifestations of iNPH has not been well elucidated. Therefore, the objective of this study was to investigate the influence of Aβ² deposition on clinical manifestations of iNPH using 11C-PiB PET.

Methods: We enrolled 46 probable iNPH patients. All patients underwent 11C-PiB PET scans, and were divided into two groups, Aβ²(+) and Aβ²(-) iNPH, according to the visual rating of 11C-PiB images. We compared the scores of modified Rankin Scale (mRS), Japanese iNPH Grading Scale (JINPHGS), Mini-Mental State Examination (MMSE), Alzheimer Disease Assessment Scale (ADAS), Frontal Assessment Battery (FAB), Timed Up and Go test (TUG), and degree of improvements after CSF shunt surgery between the two groups.

Results: Half of the 46 subjects (23/46) were determined as Aβ²(+) iNPH. Clinical evaluations, including mRS, gait and cognitive scores of JINPHGS, MMSE, ADAS, and TUG demonstrated that the Aβ(+) iNPH patients showed significantly worse performances than those in Aβ²(-) iNPH. The score of MMSE was inversely correlated with the time of TUG only in the Aβ²(+) iNPH group, suggesting that co-existence of AD pathology enhances the clinical manifestations of iNPH. Additionally, the Aβ²(+) iNPH group showed less improvements after the shunt surgery than Aβ²(-) iNPH.

Conclusions: Results demonstrated that 50% of the probable iNPH patients had cortical Aβ² deposition, indicating high prevalence of co-existing AD pathology. Comorbidity of AD pathology can affect clinical symptoms, as well as the outcomes of the shunt surgery. Therefore, comorbidity of AD should be taken into consideration when we treat iNPH.

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P124: PREVALENCE OF NPH IN A MEMORY CLINIC IN A NEUROLOGICAL SETTING.

Anne Mette Hejl, Hanne Wakabayashi, Sarah Taudorf, Birgitte Andersen, Steen Hasselbalch

Danish Dementia Research Centre, Copenhagen, Denmark Introduction: Potentially reversible dementias are important to identify. The diagnosis of Normal Pressure Hydrocephalus (NPH) relies on the clinical evaluation, brain imaging and often supplementary tests, such as lumbar infusion test and/or lumbar tap test. Although the diagnostic evaluation is well described, it is difficult to identify which subject would benefit from surgery.

The aim was to investigate the diagnostic evaluation and prevalence of shunt surgery in a one year population of patients referred to clinical evaluation of NPH in memory clinic in a neurological setting.

Methods: All patients referred to diagnostic evaluation of possible NPH were included. A multidisciplinary staff of neurologists and neurosurgeons established a standardised consensus report for each patient based on results of clinical investigations with classification of cognitive profile, brain imaging, and lumbar infusion test.

Results: In 2013 we had 204 referrals for possible NPH. Mean age was 74.3 years (range 41-92). Mean Mini Mental Examination was 23.1(range 6-30). Clinical suspicion of NPH was found in 73 (36%) of the patients. These patients had a lumbar infusion test. VP shunt operation was performed in 35 patients (48%). Three months follow-up data is currently available in 21 patients. Eighteen out of 21 patients improved in one or more of their symptoms, primarily gait and balance, whereas 3 patients did not improve. Of the 169 patients who were not diagnosed with NPH, 22% was diagnosed with vascular dementia, 17% with Alzheimer’s disease, and 10% with Parkinson’s disease/ Lewy body dementia. 11% of the referrals had neither gait problems, incontinence nor cognitive complaints.

Conclusion: The occurrence of NPH is rare, but important to identify. VP shunt operation improved at least one symptom in the majority of patients. Vascular disease and neurodegenerative disease are the most important differential diagnoses.

NORMAL PRESSURE HYDROCEPHALUS

P125: EFFECT OF LUMBOPERITONEAL SHUNT ON NEUROPSYCHIATRIC SYMPTOMS IN THE PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS

Hideki Kanemoto, Hiroaki Kazui, Yukiko Suzuki, Shunsuke Sato, Kenji Yoshiyama

Division of Psychiatry Osaka University Graduate School of Medicine, Osaka, Japan Introduction: It is known that patients with idiopathic normal pressure hydrocephalus (iNPH) have neuropsychiatric symptoms and the symptoms affect the quality of life of iNPH patients along with their triad of symptoms. Lumboperitoneal shunt (L-P shunt) operation is proved to improve the triad symptoms of iNPH patients, but the effect on neuropsychiatric symptoms was not reported. We assessed the effect of L-P shunt on neuropsychiatric symptoms in iNPH patients.

Methods: We recruited 22 iNPH patients whose clinical symptoms improved after L-P shunt operations. Neuropsychiatric symptoms of the patients were evaluated with the Neuropsychiatric Inventory (NPI) before and three months after the operations. NPI is the tool to assess 12 behavioural disturbances in dementia patients: delusion, hallucinations, dysphoria, anxiety, agitation, euphoria, disinhibition, irritability, apathy, aberrant motor activity, sleep disturbance, and appetite and eating abnormalities. The frequency and the severity of each manifestation are scored with positive responses to screening questions, and sum of the composite scores (severity x frequency) is calculated as total NPI score. Higher scores of NPI indicate worse neuropsychiatric symptoms.

Results: The most frequently observed neuropsychiatric symptom in the iNPH patients before the operations was apathy (86.4%) followed by depression(36.4%), agitation(31.8%), and irritability(31.8%). The mean total NPI scores significantly decreased after the operations (before: 14.0 ± 9.9 vs. after: 6.6 ± 6.5, p<0.001). After the operations, the scores of four manifestations in NPI, depression, apathy, irritability, and appetite and eating abnormalities, significantly decreased.

Conclusion: L-P shunt operation is useful to improve, not only the triad symptoms, but also the neuropsychiatric symptoms in iNPH patients.

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P126: VARIABILITY OF FUNCTIONAL MOBILITY IN PATIENTS WITH IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS AND ITS INFLUENCE ON THE GAIT ASSESSMENT

Yukiko Suzuki, Shunsuke Sato, Hiroaki Kazui, Hideki Kanemoto, Kenji Yoshiyama, Masatoshi Takeda Division of Psychiatry Osaka University Graduate School of Medicine, Osaka, Japan

Introduction: Functional mobility is variable in a patient with idiopathic normal pressure hydrocephalus (iNPH). We evaluated the degree of variability of functional mobility and its influence on CSF tap test in iNPH patients.

Methods: The subjects were12 patients with iNPH (male/female: 8/4, age 75.1±5.2 years old, MMSE 23.8±3.5) whose clinically symptoms improved after shunt surgery. 3m-timed up and go test (TUG) is a test for evaluating functional mobility. In this test, the time it takes a subject sitting in an armchair to stand up, walk forward 3 m and return to the seated position is measured. In this study, the TUG was performed on the 12 iNPH patients four times a day: twice in the morning and twice in the afternoon. The fastest time among the four evaluations in a day was defined as FTD. This procedure was repeated for 10 days in each patient: for 5 days before CSF tapping and 5 days after CSF tapping, in which 30ml of CSF was removed once by lumber puncture.

Results: The fastest FTD in five days was significantly longer before CSF tapping than after CSF tapping (before 11.8±3.0 sec vs. after 10.4±2.1 sec, p=0.002). The difference between the fastest and latest FTD in five days was larger before CSF tapping than after CSF tapping (before 3.1±2.1 sec vs. after 2.0±1.7 sec, p=0.03). If the fastest FTDs were used to compare between before and after CSF tapping, seven of the 12 patients did not reach the improvement of 10% on the TUG.

Conclusion: The results of TUG in iNPH patients were variable and we have to take the variability of functional mobility into consideration when the TUG was used in the CSF tap test.

NORMAL PRESSURE HYDROCEPHALUS

P127: FINITE ELEMENT ANALYSIS FOR NORMAL PRESSURE HYDROCEPHALUS: THE EFFECTS OF THE INTEGRATION OF SULCI

Hakseung Kim1,W Dae-Hyeon Park1, Byung C Yoon2, Byung-Jo Kim3, Marek Czosnyka4, Michael Sutcliffe5, Dong-Joo Kim1

1 Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea 2 Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, USA 3 Department of Neurology, Korea University College of Medicine, Seoul, South Korea 4 Department of Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom 5 Department of Engineering, University of Cambridge, Cambridge, United Kingdom

Background: Finite element model (FEM) analysis is increasingly used for investigating the brain under various pathological changes. Hydrocephalus has been the subject of FEM studies for decades; however previous studies have mainly focused on ventriculomegaly. The presented study aims to investigate the pathologic changes regarding the sulcal deformation in hydrocephalus.

Methods: Two FE models, anatomical brain geometric model (ABG) and the conventional simplified brain geometric model (SBG), of normal pressure hydrocephalus were constructed. The models were constructed to have identical boundary conditions, but different geometries. The ABG contained details of sulci geometry, whereas in SBG these features were omitted. The resulting pathologic changes were assessed via four biomechanical parameters: pore pressure, von Mises stress, volumetric strain, and void ratio. Initiation of hydrocephalus were induced by increasing transmantle pressure gradient (TPG) from 0 to maximum of 2.0 mmHg.

Results: Both models successfully simulated the major features of hydrocephalus (i.e. ventriculomegaly and periventricular lucency). The trends in changes of biomechanical parameters with increasing TPG were similar. However, the SBG underestimates the degree of stress across the cerebral mantle by 150% than ABG. The SBG also incorrectly models the periventricular lucency when TPG reaches 2.0 mmHg (pore pressure > 0 mmHg), and may underestimate the degree of ventriculomegaly (116.58% and 157.88% increase at TPG = 2.0 mmHg, for SBG and ABG respectively).

Conclusions: Inclusion of the sulci geometry within an FE model for hydrocephalus clearly affects the overall results. The conventional SBG is inferior to the ABG which accurately simulate sulcal deformation and consequent effects on cortical or subcortical structures. The inclusion of sulci in future FE models of brain is strongly advised, especially for models for investigating space occupying lesions.

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P128: EFFECT OF CHANGES IN SERUM AND CEREBROSPINAL FLUID OSMOLARITY ON CEREBROSPINAL FLUID VOLUME AND METABOLITE CONCENTRATIONS

Jurica Marakoviä1, Darko Oreäkoviä2, Milan Radoš3, Darko Chudy1, Marijan Klarica4

1Department of Neurosurgery, Dubrava University Hospital, Zagreb, Croatia 2 Department of Molecular Biology, Ruder Boskovic Institute, Zagreb, Croatia 3 University of Zagreb, School of Medicine, Croatian Institute for Brain Research , Zagreb, Croatia 4University of Zagreb, School of Medicine, Department of Pharmacology and Croatian Institute for Brain Research, Zagreb, Croatia

Introduction: We previously demonstrated that changes of serum and cerebrospinal fluid (CSF) osmolarity change the CSF volume and pressure because of the osmotic exchange of water between central nervous system (CNS) blood capillaries, interstitial fluid and all CSF compartments, which is in accordance with our newly proposed CSF physiology hypothesis. Thus, we could expect that acute CSF volume changes influence the CSF concentration of CNS metabolites normally present in CSF.

Method: On anesthetized cats (n=4), we measured the outflow CSF volume by cisternal free drainage at negative CSF pressure (-10 cm H2O) before and after the intraperitoneal (i.p.) application of hypo-osmolar substance (distilled water). In samples of CSF collected at different time intervals (30 min), we measured the homovanillic acid (HVA) concentration.

Results: Several minutes after free cisternal drainage beginning, the constant CSF outflow volume was obtained, but HVA concentration gradually increased over time, and became stable after 90 minute period. After the i.p. application of distilled water, the outflow CSF volume significantly increased while HVA concentration significantly decreased during 30 min.

Conclusions: Our results demonstrated that acute changes in serum osmolarity change the CSF volume and CSF concentrations of HVA because of the osmotic arrival of water from CNS blood capillaries into all CSF compartments. These results also contradict the classic hypothesis of CSF secretion, unidirectional circulation and absorption, but additionally support our new hypothesis on CSF hydrodynamics.

EXPERIMENTAL HYDROCEPHALUS

P129: CSF OSCILLATIONS IN THE CRANIUM: TOWARD THE VENTRICLES OR THE SUBARACHNOID SPACES

Simon Garnotel1, Stéphanie Salmon2, Olivier Balédent1

1University Hospital, Amiens, France 2Mathematical University, Reims, France Background: During the cardiac cycle, in response of the net vascular oscillation in the cranium, the CSF oscillates both from the ventricles (VENT) and from the intracranial subarachnoid spaces (INTRA-SAS) in the spinal canal (SPINAL-SAS). Most of the patients with an active hydrocephalus present a large increase in CSF dynamics in VENT.

The aim is to understand how heart rate, compliances and resistances to flow can influence the CSF oscillations in the ventricles.

Methods: A simple numerical model is done with two compliant spheres (VENT and INTRA-SAS) connected by a tube (narrow one to mimic the aqueduct pathway and a large one to mimic INTRA-SAS) to a third tube mimicking the SPINAL- SAS. Solving the Navier-Stokes equations using the finite element method performs the numerical fluid simulation. The CSF flow in the SPINAL-SAS previously measured by phase contrast magnetic resonance imaging is considered as an input function of the simulation. The CSF flow in VENT and INTRA-SAS are the results of the computation. Different values of: the heart rate, the compliances and the resistances are tested.

Results: The Graphs of CSF Flow in VENT and INTRA-SAS, functions of the tested values are obtained. For example, in our model, the flow rate can be higher in INTRA-SAS than in VENT if heart rate = 60 bpm whereas flow rate is higher in VENT if the heart rate = 30bpm. For a given compartment, compliance decrease causes a flow rate decrease; resistance increase causes a flow rate decrease. The Heart rate, compliances and resistances have non-linear impacts on the CSF distribution between VENT and INTRA-SAS. These parameters have also an impact on the fluid pressure in the different compartments.

Conclusions: Heart rates, compliances and resistances can favour CSF flow in the ventricles’ compartment and thus increase its volumes and develop hydrocephalus.

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P130: RESISTANCE TO CSF OUTFLOW IN PREDICTING POSTOPERATIVE IMPROVEMENTS OF SHUNTED NPH PATIENTS

Hakseung Kim1 W Dae-Hyeon Park1, Byung C Yoon2, Byung-Jo Kim3, Marek Czosnyka4, Michael Sutcliffe5, Dong-Joo Kim1

1 Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea 2 Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, USA 3 Department of Neurology, Korea University College of Medicine, Seoul, South Korea 4 Department of Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, United Kingdom 5 Department of Engineering, University of Cambridge, Cambridge, United Kingdom

Introduction: The disturbance in cerebrospinal fluid (CSF) absorption capacity is considered as one of the main causes of normal pressure hydrocephalus (NPH). The resistance to CSF outflow (R_OUT) can be understood as a surrogate for the degree of such disturbance, thus has been used as a supplementary parameter in anticipating shunt responsiveness. Nevertheless, despite decades of usage, no widely accepted threshold of R_OUT for detecting shunt responders exists.

Methods: Four cut-off values of R_OUT (10, 12, 15 and 18 mmHg/ml/min) reported by earlier studies were selected as potential thresholds. A systemic review of existing studies regarding NPH, shunt surgery and the R_OUT was conducted.

Results: A total of eight studies were finally selected for the meta-analyses. The odds ratios of the four thresholds were found to be 3.78, 4.56, 3.79 and 3.19 (for 10, 12, 15 and 18 mmHg/ml/min of R_OUT, respectively). R_OUT of 12 mmHg/ ml/min provided the highest accuracy (74.94%), with high sensitivity (83.01%) and moderate specificity (49.48%).

Conclusions: The presented study concludes R_OUT of 12 mmHg/ml/min as the most suitable threshold in predicting shunt responsiveness for NPH patients.

CSF DYNAMICS

P131: HYDROCEPHALUS AS A COMPLICATION OF FORAMEN MAGNUM DECOMPRESSION FOR CHIARI I MALFORMATION

John Duddy, John Caird

Beaumont Hospital, Dublin, Ireland

Introduction: The aim of surgery for Chiari I malformation is to relieve symptoms by restoring CSF circulation at the foramen magnum. The procedure is associated with a number of complications, including post-operative nausea and vomiting, wound infection and lack of symptom improvement. It had been originally thought that hydrocephalus was a rare complication of foramen magnum decompression (FMD). However, recent evidence has shown it is more prevalent than originally thought. Our aim was to determine the number of CSF-related complications after FMD for Chiari I malformation.

Methods: A retrospective chart review was carried out for all FMDs for Chiari I malformation over a three year period. Post-operative outcomes were recorded and analysed, along with patient demographic details, and other relevant medical conditions.

Results: 54 patients were eligible for inclusion, 40 female (74%) and 14 male (26%). Average age was 32.1 years (range 7-70). In total, 10 (18.5%) patients developed hydrocephalus requiring shunting. Two of these presented with CSF leak. One was initially managed with lumbar drain but eventually required permanent VP shunting. The other was managed with a lumbo-peritoneal shunt. The rest presented with a range of symptoms including headache, nausea, vomiting and drowsiness. Four of the shunted patients required further shunt-related procedures. Two patients with hydrocephalus also developed subdural hygromas which required burrhole evacuation prior to shunting. Seven of the ten patients who developed hydrocephalus had duraplasty performed. Of these, five had a bovine-derived collagen-based matrix graft and the other two had synthetic grafts.

Conclusions: This series reports a hydrocephalus rate of 18.5%. Hydrocephalus is a real risk after FMD for Chiari I malformation and such patients can be difficult to manage, often requiring multiple procedures. It is possible that duraplasty, or the use of bovine-derived collagen-based matrix dural grafts may contribute to the development of hydrocephalus.

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P132: DOES A CSF SHUNT DISCONNECTION ALWAYS NEED FURTHER INVESTIGATION? Patricia De Lacy, Sally Ushewokunze, John Mcmullan

Sheffield Teaching Hospitals NHS Trust, United Kingdom

Introduction: There is no gold standard among UK neurosurgeons for the management of disconnected CSF shunts. There is also minimal literature to advise as to the best management for these patients.

Methods: We have just over 400 adult patients with hydrocephalus due to various aetiologies under annual follow up at our unit. The aim of this retrospective study was to identify any patients with a past history of shunt disconnection and to analyse the investigations that were performed and whether a shunt revision was carried out. We searched the electronic clinic letters written by the Hydrocephalus Specialist Nurse over a period of 6 years from 2008 until June 2014. We then reviewed the clinical notes in order to identify their presenting symptoms & signs, site of shunt disconnection/fracture, investigations & surgery performed if deemed necessary.

Results: 40 patients were identified to have had a past history of a disconnection in their CSF shunt system; either VA, VP or V-pleural systems. A small proportion of these patients presented as an emergency with symptoms and signs of raised ICP. Many patients were asymptomatic and the subsequent investigations for theses patients ranged from purely annual clinical review, ophthalmology assessment to rule out papilloedema to ICP monitoring +/- shunt revision. The site of disconnection was most commonly in the cervical region.

Conclusions: The investigation and management for our 40 patients was very varied. Those patients who presented with symptoms of raised ICP underwent a shunt revision. None of our patients had a complete shunt removal for a disconnected shunt without insertion of a new shunt system. This is different to a series published by Lee YH et al (2010).

References: Lee YH et al ‘What should we do with a disconnected shunt? Child’s Nervous System 26(6)791-6, June 2010.

ADULT HYDROCEPHALUS

P133: VENTRICULO-PLEURAL SHUNTS IN ADULTS: AN EFFECTIVE AND DURABLE SECONDARY PROCEDURE

Amna Farrukh, Ahmed Toma, Samir Matloob, Mustafa Anjari, Flavia Somavilla, Patricia Haylock-Vize, Laurence Watkins

Department of Neurosurgery, The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom Background: Ventriculo-peritoneal shunts constitute the conventional procedure for diversion of CSF. Pleural diversion of cerebrospinal fluid (CSF) is not the initial choice owing to risk of pleural effusion, pneumothorax and structural or functional shunt obstruction. In this study we assessed the efficacy and survival of ventriculo-pleural shunts as a suitable subsequent step following ineffective peritoneal drainage.

Methods: A retrospective case study was conducted for ventriculo-pleural shunt insertions and revisions over a period of 5 years. Data was collected including the number of CSF diverting surgical interventions preceding ventriculo-pleural shunt insertion. Complications and survival rates of ventriculo-pleural shunts were recorded and correlated with the type of anti- siphon device used.

Results: From 2009 to 2014, forty one ventriculo-pleural shunts were inserted or revised for twenty one patients aged between 20 - 74 years (mean +/- standard deviation (SD) 40.43 +/- 13.98 years). The mean number of shunt related surgical interventions prior to pleural diversion of CSF was 5.62 (SD +/-3.64). The mean follow up period for these patients was 2.04 years (range 71 days to 3.9 years, SD +/- 1.31 years). 57% of the ventriculo-pleural shunts needed revision and the mean survival of ventriculo-pleural shunts for patients who ultimately had surgical revision was 2.62 years. Shunt tubing retraction or displacement were the commonest causes for revision (38%), followed by respiratory insufficiency (pleural effusion and pneumothorax) 24% and infection 9%. There were no mortalities from complications or shunt dysfunction.

Conclusion: There is a significant reduction in surgical interventions following insertion of a ventriculo-pleural shunt in this patient group. Ventricular-pleural shunts provide a valuable, safe and adequate substitute for diversion of CSF in adults, when the peritoneal cavity is an unsuitable drainage site.

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P134: INFLUENCE OF CRANIOPLASTY TIMING ON HYDROCEPHALUS AFTER DECOMPRESSIVE CRANIECTOMY

Tomas Radovnicky, Ales Hejcl, Martin Sames

Department of Neurosurgery, Usti nad Labem, Czech Republic Introduction: Decompressive craniectomy is a procedure with serious complications. One of them is post-operative hydrocephalus, which worsens prognosis. The pathophysiology of hydrocephalus development is not clear; it seems to be multifactorial. Our study was aimed to find a relationship between hydrocephalus persistence and the timing of cranioplasty.

Methods: In our retrospective study 80 patients with decompressive craniectomy (40 patients for acute subdural hematoma and 40 patients for post ischemic edema) were involved. Age range from 19 to 76 years (mean 61 years). The presence of hydrocephalus was evaluated by the radiological signs before and after the cranioplasty. Patients with pre-cranioplasty hydrocephalus were divided into two groups according to post-cranioplasty hydrocephalus persistence.

Results: Pre-cranioplasty hydrocephalus was observed in 34 patients (42,5%). 18 patients underwent surgery for acute subdural hematoma and 16 patients for ischemic stroke. After the cranioplasty no signs of hydrocephalus were found in 12 patients (35,3%). The mean time period between the decompressive craniectomy and the cranioplasty in the persistent hydrocephalus group was 58 days, and in the non-persistent group 20 days.

Conclusions: Hydrocephalus after the decompressive craniectomy is a frequent complication, no matter if it was performed for subdural hematoma or ischemic stroke. To prevent hydrocephalus persistence, early cranioplasty is recommended. Shunt implantation and cranioplasty should not be performed in one session, because cranioplasty can restore normal cerebrospinal fluid dynamics.

ADULT HYDROCEPHALUS

P135: HISTOPATHOLOGICAL COMPARISON OF IDIOPATHIC NORMAL PRESSURE HYDROCEPHALUS AND LONGSTANDING OVERT VENTRICULOMEGALY IN ADULTS

Chihiro Akiba, Masakazu Miyajima, Madoka Nakajima, Ikuko Ogino

Department of Neurosurgery, Juntendo University Graduate School of Medicine, Tokyo, Japan Introduction: Two hydrocephalus-dementia complex related conditions: idiopathic normal pressure hydrocephalus (iNPH) and long-standing overt ventriculomegaly in adults (LOVA) might be a subject of overlapping and misinterpretation. Many non-Japanese studies include LOVA hydrocephalus as a form of iNPH. However, only a very small number of studies have conducted pathological examinations in iNPH and LOVA, and much remains unknown regarding the pathological findings details characterizing them.

Methods: Three autopsy cases of iNPH (age 68-80 years, three males) and one autopsy case of an elderly male (age 82 years) diagnosed with LOVA hydrocephalus presenting with marked ventriculomegaly were examined and compared.

Results: All iNPH brains at autopsy demonstrated widespread white matter perivascular sclerosis and mild microvessel wall thickening. Nonreactive astrocytes had particularly reduced immunoreactivity for aquaporin 4 (AQP4). Microvascular sclerosis could be hypothetically attributed to abnormalities in cerebrospinal fluid dynamics in iNPH. Ventriculomegaly was more pronounced in LOVA than in iNPH and the distribution of leukoaraiosis was comparable between the two conditions. We found differences in fibrillary gliosis in the white matter, the character of the lesions, and the degree and distribution of microvascular sclerosis. The underlying pathology of dementia in LOVA was considered a combination of hydrocephalus, hypertensive angiopathy, and tauopathy.

Conclusions: Although the distribution of leukoaraiosis in iNPH was similar to that in LOVA, the character of the lesions and the degree and distribution of microvascular sclerosis were different. Microvascular sclerosis may reflect abnormalities in cerebrospinal fluid dynamics in iNPH.

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P136: EVALUATION OF INTERNET DERIVED PATIENT INFORMATION ON HYDROCEPHALUS

James Ward, Paul Leach

University Hospital Wales, Cardiff, Wales

Abstract:

Introduction: The internet is a widely used, powerful resource for patients to research medical conditions. There is an extensive amount of information available on the internet. It is important for patient information to be accurate and in an easily accessible format. This article aims to assess the quality of patient information on hydrocephalus and compares the findings with recent evaluations in other surgical specialties.

Methods: The term “hydrocephalus” was searched for on the search engines http://www.google.com/, http://www.bing. com/ and http://www.yahoo.com/. The top 20 results of these searches were assessed using the University of Michigan consumer health website evaluation checklist.

Results: The quality of patient information websites on hydrocephalus is highly variable. Websites rarely provide sufficient authorship information, do not review their information regularly enough and only reference material occasionally. The back- ground of the provider was found to influence the quality of the website, with academic and care providers creating the best websites.

Conclusions: On comparing our findings with those of recent studies from other surgical specialties, it was found that there was often a conflict of interest between the background of the provider and the information supplied. It is recommended that clinicians personally research material for their patients to be able to guide them to suitable, accurate websites.

ADULT HYDROCEPHALUS

P137: FOLLOW-UP ANALYSIS OF VENTRICULO-ATRIAL SHUNTS: EXPERIENCE AT A SINGLE INSTITUTION

Emilio González-Martínez, Cristina Silva, Luis Martínez Soto, Soraya González Rodriguez, Sonia Facal, Romualdo Ferreira

University Hospital of Álava, Vitoria, Spain Introductions: Ventriculo-atrial (VA) shunt has been classically relegated to a second place for the treatment of hydrocephalus likely due to eventual cardiovascular complications. We review our experience in VA shunt in 59 patients emphasizing on their complications.

Methods: We perform a retrospective analysis of 59 consecutive patients underwent VA shunts. Demographic data, cause of placement, reason of the election of the VA shunt, complications and follow-up time were recorded.

Results: The mean age was 68 years old (range: 18–89) with male predominance (59.3%). Forty-one patients suffered from idiopathic normal pressure hydrocephalus (69.5%), 10 from non-communicating hydrocephalus (17%), 6 from communicating hydrocephalus (10.2%) and 2 from postoperative fistula (3.3%). Twenty-five shunts were primarily implanted into atrium (42.4%). The main reason for atrial implantation was prior shunt malfunction (35.6%) following preference of the neurosurgeon (32.2%) and abdominal contraindications (32.2%).

Median follow-up was 23.9 months (95% Confidence Interval 16.8-31 months). Over-drainage manifestations were present in 7 patients (11.9%) (subdural effusion in 4 and low-pressure headache in 3) and shunt malfunction in 4 (6.8%). Other complications valve-related were: 4 cases of exposition, two cases of disconnection of the system (3.4%) and two infections. One patient suffered from postoperative intraventricular haemorrhage that caused shunt malfunction, and two patients presented mild intracranial haemorrhage.

Interestingly, 6 patients died from traumatic acute subdural haematoma during the follow-up. Nine patients required replacement of the shunt (15.3%), two cases of the atrial catheter and one case of the ventricular catheter. One shunt was definitively removed.

Conclusions: In our experience, atrial catheter of cerebrospinal fluid diversion does not add significant comorbidities to the shunt. Therefore, this variation can constitute an option to consider not only in malfunction of VP shunt but also as first-line option.

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P138: TEMPORAL CHANGES IN EXPRESSION OF FDH AND FR ALPHA IN HYDROCEPHALUS: A COMPARISON BETWEEN HYDROCEPHALIC AND NORMAL RATS

Naila Naz, Anna Sanjuan, Sally Ashe, Jaleel Miyan

Neurosciences, Manchester, United Kingdom

Background: Folate plays an important role in brain development. In rodents and humans, disruption in cerebral folate metabolism is associated with fetal-onset-hydrocephalus. The present study aimed to determine expression pattern of major components (5MTHF, FDH and FR-alpha) of folate metabolism during brain development.

Methods: We compared the hydrocephalic-Texas (H-Tx) rat with the non-hydrocephalic Sprague dawley (SD) rat. H-Tx rat is a well-established model of fetal-onset hydrocephalus (HC), which recapitulates clinical human HC. H-Tx progeny were designated as either affected: A-HTx or unaffaected: U-HTx based on gross morphological analysis. Brains from both rat strains were harvested at specific gestational time-points and postpartum. Brain tissue was analysed by Western blot and dot blot analysis. PFA fixed brain tissues were processed for immunofluorescence staining.

Results: In SD and U-HTx animals, a progressive decrease in 5MTHF and THF was observed during development. However, in A-HTx animals, during fetal development an increase in both folates was observed which tended to fluctuate in postnatal ages. An increasing protein expression of FDH and FR-alpha was observed in SD and U-HTx rat brains but FR-alpha showed variable expression in both categories of HTx rat brain during development. An increased expression of FDH protein was detected in A-HTx during development. The expression level of these two proteins was found to be associated with the severity of hydrocephalus.

5MTHF was co-localized with FDH and FR-alpha in both strains. More surprisingly, in post natal stages, a very intense nuclear expression of FDH was observed in cortical cells. In contrast to SD, A-HTx brains demonstrated increased numbers of FDH+ve granules in peri-ventricular cells. Moreover, FDH nuclear localization was not obvious in A-HTx brains.

Results: These data demonstrate a difference in expression pattern of major components of folate metabolism in hydrocephalic animals during development. Absence/reduction of nuclear FDH in A-HTx needs further investigation as it is not clear whether this is a potential cause or a consequence of hydrocephalus.

EXPERIMENTAL HYDROCEPHALUS

P139: CHANGES IN EXPRESSION OF HEPATIC FDH IN HYDROCEPHALUS: A COMPARISON BETWEEN HYDROCEPHALIC AND NORMAL RATS

Anna Sanjuan Vilaplana, Jaleel Miyan, Naila Naz Neurosciences, Manchester, United Kingdom

Introductions: Ventriculo-atrial (VA) shunt has been classically relegated to a second place for the treatment of hydrocephalus likely due to eventual cardiovascular complications. We review our experience in VA shunt in 59 patients emphasizing on their complications.

Methods: We perform a retrospective analysis of 59 consecutive patients underwent VA shunts. Demographic data, cause of placement, reason of the election of the VA shunt, complications and follow-up time were recorded.

Results: The mean age was 68 years old (range: 18–89) with male predominance (59.3%). Forty-one patients suffered from idiopathic normal pressure hydrocephalus (69.5%), 10 from non-communicating hydrocephalus (17%), 6 from communicating hydrocephalus (10.2%) and 2 from postoperative fistula (3.3%). Twenty-five shunts were primarily implanted into atrium (42.4%). The main reason for atrial implantation was prior shunt malfunction (35.6%) following preference of the neurosurgeon (32.2%) and abdominal contraindications (32.2%).

Median follow-up was 23.9 months (95% Confidence Interval 16.8-31 months). Over-drainage manifestations were present in 7 patients (11.9%) (subdural effusion in 4 and low-pressure headache in 3) and shunt malfunction in 4 (6.8%). Other complications valve-related were: 4 cases of exposition, two cases of disconnection of the system (3.4%) and two infections. One patient suffered from postoperative intraventricular haemorrhage that caused shunt malfunction, and two patients presented mild intracranial haemorrhage.

Interestingly, 6 patients died from traumatic acute subdural haematoma during the follow-up. Nine patients required replacement of the shunt (15.3%), two cases of the atrial catheter and one case of the ventricular catheter. One shunt was definitively removed.

Conclusions: In our experience, atrial catheter of cerebrospinal fluid diversion does not add significant comorbidities to the shunt. Therefore, this variation can constitute an option to consider not only in malfunction of VP shunt but also as first-line option.

117 Organising Committees

Local Organising Committee, Hydrocephalus 2014

Richard Edwards, Congress President

Ian Pople

Michael Carter

Greg Fellows

William Singleton

Kevin Tsang

Adam Williams

Marcus Bradley

Elizabeth Coulthard

Reiko Ashida

Amr Mohammed

Neil Barua

Savithru Prakash

Richard Nelson, President, Society of British Neurological Surgeons

Victoria Hancock, In Any Event, UK

Jonathan Moore, 10pdm.com

International Organising Committee, Hydrocephalus 2014

Michael Williams, USA, President, ISHCSF

Laurence Watkins, UK, President Elect, ISHCSF

Daniele Rigamonte, USA, Secretary, ISHCSF

Mark Hamilton, Canada

Etsuro Mori, Japan

Uwe Kehler, Germany

Brian Owler, Australia

Anders Ekland, Sweden

118 Author Index

Name Page Number

Abbas Alnaji 105 Abdulrahman Almutairi 48 Abhay Moghekar 58 85 Abhaya Kulkarni 18 28 Ahmed Toma 60 91 94 101 102 108 114 Akbar Khan 63 108 Akihiko Ozaki 62 49 62 Akihiko Iida 66 Akinori Nakamura 109 Akira Watanabe 86 Alasdair Parker 59 Albert Erasmus 48 93 100 Ales Hejcl 115 Alex Mortimer 50 Alexander Lilja 53 59 Alexandre Reymond 57 Amanda Braun 73 Amélie Baud 57 Amna Farrukh 91 94 114 Anders Behrens 91 Anders Eklund 54 85 86 91 André Ahlgren 49 Andrea Porelti 23 Andrew Edwards 57 Andrew Gauden 100 Andrew Hunn 48 93 100 Anette Hall 54 Angelo Maset 71 Ann Logan 21 29 Anna Jeppsson 61 Anna Mikhaleva 57 Anna Sanjuan Vilaplana 177 Anna Sutela 55 55 Annakaisa Haapasalo 109 Anne M Koivisto 55 55 Anne Remes 55 55 Anne-Mette Hejl 110 Anthony Amato-Watkins 83 Anthony Birch 56 Anthony Fichten 98 Antonio Ficola 78 Antonio Petoši 75 Antti Junkkari 88 Antti Luikku 54 Ari Blitz 27 99 51 53 62 67 92 99 103 Arthur Ellice-Flint 100 Arun Chandran 60 Arvind Dubey 48 93 100 Asad Sheikh 48 93 Asim Mujic 48 93 100 Aya Sakurai 75 AYODEJI YUSUF 104 Ayota Nohara 64 Bader Chaarani 84 98 Badri Roysam 83 Barbara Crain 85 Bassel Zebian 65 100 Benedetta Pettorini 65 100 Benjamin Hunn 48 93 Bienvenido Puerto 82 Bill Shain 83 Binnaz Yalcin 57 Birgitte Andersen 110 Branka Mucić-Pucić 97 Brian Hanak 65 Brian Kim 106 Bruno Mancini 70 71 Bryn Martin 23 Byung C Yoon 67 111 113 Byung-Jo Kim 106 111 113 Carmelo Anile 78 Carmen Cabellos 92 Carolyn Harris 83 27 Carsten Wikkelsö 21 27 54 55 56 57 61 81 Catherine Gondry-Jouet 84 102

119 Name Page Number Catherine Harris 60 Charles Vorhees 73 Chieko Ishikawa 75 Chihiro Akiba 63 115 Chris Chandler 65 100 101 Chris Kellett 63 101 Chris Parks 100 Christel Wagner 57 Christer Jensen 55 57 Christian Sprung 71 73 82 Christoffer Blegvad 96 Christoph Miethke 79 105 Christopher Lelliott 57 Christos Chamilos 100 Claire Doody 50 50 50 Conor Mallucci 19 52 28 28 65 100 Cristina Silva 116 117 Curtis Lee 106 Cyrille Capel 68 84 95 98 102 Dae-Hyeon Park 67 111 113 Daisuke Ito 75 Daisuke Kita 74 93 Dan Farahmand 54 81 Daniel Jaraj 55 57 Daniele Rigamonti 23 51 53 58 62 67 85 88 89 99 103 Darko Chudy 112 Darko Oreškoviβ 75 97 112 David Adams 57 David Limbrick 23 David Santamarta 77 79 82 David Solomon 23 58 62 103 David Solomon 23 58 62 103 Davids Qeays 57 Diana Lindquist 73 Diederik Bulters 56 56 Dionéia Monte-Serrat 104 Dionei Moraes 70 71 104 Dominic Wilkinson 21 29 Dong-Joo Kim 67 111 113 Dora Mandic 97 Dorthe Christoffersen 53 53 53 Ellis Meng 106 Elna-Marie Larsson 49 Emi Hayashi 66 Emilio González-Martínez 77 79 117 Eric Sankey 51 53 67 99 Erin Hooper 65 Esreil Killer 58 Etsuro Mori 48 49 50 61 66 80 95 Eun-Jin Jeong 67 Eva Elgh 91 Fady Girgis 51 Fergus Robertson 101 102 Fernado Hakim 88 Flavia Somavilla 91 94 114 Florian Freimann 72 73 Florine Dallery 84 Francesco Mangano 73 Francis Loth 76 Francisco Estupiñan 87 George Prezerakos 102 George Razay 90 German Letyagin 103 Gloria Villalba 87 Grant Bateman 23 Greg Fellows 96 Gulam Zilani 83 Guo-qiang CHEN 52 107 Gustavo Botelho 70 71 H Yamada 75 Hajime Arai 63 48 63 69 89 Hakseung Kim Kim 67 111 113 Harold Rekate 23 Han-Lin Yen 97 Hanna Israelsson 85 86 Hannah Botfield 21 29 Hanne Wakabayashi 103 110 Hans Nahser 60 Hans-Joachim Crawack 71 Harel Gadot 70 Harri Sintonen 88 Harumasa Kasai 49 Heimo Viinamäki 88 Helen Whitley 57

120 Name Page Number Henrik Zetterberg 61 61 Hideki Kanemoto 110 111 Hilkka Soininen 55 55 109 Hiroaki Kazui 49 50 80 88 110 111 Hirohito Kan 49 Hiroji Miyake 77 87 90 Hiroki Toda 62 49 62 Hiroshi Kageyama 69 Hiroshi Yamada 49 66 Hiroyuki Arai 50 50 50 Hisashi Hatano 64 Hisayuki Murai 76 101 Iain Robertson 90 Ibrahim Djoukhadar 69 Ignacio Jusue-Torres 51 53 67 85 88 89 92 Ikuko Ogino 63 48 63 69 115 Imran Bhatti 83 Ines Nikic 97 Ingmar Skoog 55 57 Ingolf Sack 19 29 Irina Alafuzoff 55 55 55 Isabel Herr 57 Issei Fukui 93 Ivan Pelegrin 92 Ivana Jurjeviβ 75 Jaana Rummukainen 55 55 55 Jacob Cox 92 Jacquline White 57 Jadwiga Zmudka 68 98 Jaleel Miyan 117 James Barber 64 James Drake 20 29 James Shand Smith 108 James Ward 116 Jamie Clarke 69 Jamie Hoffberger 51 53 67 85 88 89 99 Jamie Robison 51 99 Jan Malm 28 54 85 86 92 Jan Wemmer 51 99 Javier Ariza 82 92 Javier Pérez 82 Javier Villagrasa 87 Jay Riva- Cambrin 19 28 28 Jean Estabel 57 Jean-Paul Lejeune 98 Jens Peters-Willke 48 93 100 Jeremy Macmullen-Price 69 Jérome Hodel 68 95 Jesus Aguas 87 Jianne Esterbell 57 Jia-ping ZHENG 52 107 Jie Li 74 Joachim André Grotenhuis 96 Joan Grieve 102 Joanna woz 98 Joel Daouk 102 Johan Gobom 61 61 Johan Virhammar 49 John Pickard 59 78 John Caird 113 John Duddy 113 John Kestle 20 29 JOHN MCMULLAN 114 Jonathan Clark 18 28 28 Jonathan Flint 57 Jose Andrade 70 Jose Camilo 71 Joseph Donnelly 59 70 78 Jozef Lang 83 Juan Ramon-Cuellar 88 Juha E Jääskeläinen 55 55 88 109 Juha Jääskeläinen 54 Jun Yang 76 Jurica Marakov 112 Jussi Mattila 54 Jyrki Lötjönen 54 Kaj Blennow 61 Kalyan Raman 72 Karol Migliorati 108 Katarina Laurell 49 Katharina Schregal 23 Katherine Poulgrain 100 Kathryn Carson 85 Katrin Rabiei 55

121 Name Page Number Katsutoshi Furukawa 50 50 50 Kazuhiko Yanai 50 50 50 Kazuo Yamada 49 66 Kazuya Aoki 50 89 Kelsie Pearson 83 kengo Ito 109 Kengo Uemura 62 49 62 Kenichi Nishiyama 69 Kenji Yoshiyama 110 111 Kerstin Andrén 56 56 Kevin Tsang 96 Kiminori Aoyama 66 Kiwon Kim 67 Kiyoshi Takagi 106 Kristen Trett 83 Kristina Cesarini 49 Laksman Puli 109 Laurence Watkins 27 91 94 101 102 108 114 Laurie Finch 56 56 Lawrence Yu 106 Leda Tfouni 104 Lewis Thorne 101 Luca Remonda 58 Lucas Meguins 70 71 Luis Caral 87 Luis Martinez 116 117 Luke Tomycz 65 Lynne Bilston 23 Madoka Nakajima 63 48 63 84 115 Magnus Tisell 54 56 81 Makoto Sasaki 18 28 28 Manabu Tashiro 50 50 50 Mani Puthuran 60 Marc Baroncini 68 95 98 Marco Fontanella 108 Marco Gelmini 108 Marek Czosnyka 23 59 67 70 78 111 113 Maria Irma Coudry 104 Maria Kojoukhova 54 55 55 Marianne Juhler 27 53 96 Marijan Klarica 75 97 112 Marina Ragu 97 Marine Meerschman 98 Marios Papadopoulos 20 29 Mark Haacke 74 Mark Hamilton 23 27 51 Mark Luciano 76 Martin Sames 115 Martin Schumann 20 29 Masaaki Hashimoto 93 107 Masahiko Bundo 109 89 Masahiro Oishi 74 Masakazu Miyajima 48 49 50 59 63 64 69 80 84 115 Masao Moriya 48 84 Masato Kitagawa 75 Masatoshi Takeda 111 Masatsune Ishikawa 66 27 49 50 66 80 Masayoshi Kobayashi 76 Mathuri Sakthithasan 96 Matthew Garnett 59 78 Matthew Stovell 52 Meghna Kannan 57 Mei-Lin Sung 97 Melissa Razay 90 Michael Haynes 92 Michael Jenkinson 52 Michael Sutcliffe 111 113 Michael Williams 73 5 24 27 73 Mikko Hiltunen 109 Mikko Hölttä 61 109 Milan Radoš 75 97 112 Minoru Matsuda 48 61 95 Minoru Matsuda 48 61 95 Mira Patel 85 88 89 Mitsuhito Mase 49 62 62 66 Morten Andresen 53 Moshe Shohan 70 Mustafa Ali 101 102 Mustafa Anjari 91 94 114 Naila Naz 117 Namiko Nishida 62 49 62 Nanae Nagata 62 49 62 Naokatsu Saeki 76 101 Naoki Ohno 49

122 Name Page Number Naomichi Matsumoto 69 Naoto Jingami 62 49 62 Naoyuki Samejima 50 86 89 Neil Kitchen 108 Neil Miller 58 Neil Stoodley 96 Nicholas Higgins 59 Nicholas Wetjen 23 Nobumasa Kuwana 50 86 89 Nobuyuki Okamura 50 50 50 Noriaki Kawakami 64 Noriko Miyake 69 Norio Ishiwatari 101 Nurudeen Adeleke 104 Olalekan Ajiboye 104 Olivier Balédent 68 84 95 98 102 112 Oluwaseun Akanbi 104 Or Samooha 70 Osamu Iizuka 48 56 61 69 95 Ossi Nerg 88 Pat McAllister 19 28 73 83 Patricia Barrio 82 PATRICIA DE LACY 114 Patricia Haylock-Vize 60 91 94 114 Paul Leach 83 Pedro Viladrich 92 Per Hellström 56 56 81 Per Kristian Eide 81 Pere Nogues 87 Phillipe Decq 18 28 28 Pier Paolo Panciani 108 Pietro Santini 78 Piotr Smielewski 78 Qing XIAO 52 107 Rajiv Bapuraj 23 Rashid Deane 20 29 Romualdo Ferreira 116 117 48 61 61 Ren Iwata 50 50 50 Richard Edwards 4 27 50 96 Risto Roine 88 Ritva Vanninen 55 55 55 Robert Marchbanks 19 28 56 Roberto Diaz 51 Robert Oxford 65 Robin Holmes 50 23 50 Robyn Amos-Kroohs 73 Rodrigo Pinhabel 70 71 Roger Bayston 92 Roger Bouzerar 68 84 98 102 Rory Goodwin 51 Roxanne Carrare 23 Ryoko Fukai 69 Sachin Batra 85 Saeri Matsumoto 75 Sally Ashe 117 Sally Ushewokunze 114 Samir Matloob 60 91 94 101 114 Samira Akmal 101 Samuel Browd 83 Sanj Bassi 65 100 Sara Qvarlander 54 Sarah Skovlunde Hornshøj 53 Sarah Taudorf 110 Satish Krishnamurthy 74 Segrei Kim 103 Seiichi Munesue 74 Serge El-Khoury 76 Sérgio Mascarenhas 104 Sergio Ramin 70 71 Shigeki Nakano 76 101 Shigeki Yamada 66 75 Shih-Chung Tsai 97 Shinji Ono 50 89 Shinya Yamada 21 89 Shiv Gaglani 92 Shunsuke Sato 110 111 Simon Agerskov 57 Simon Garnotel 102 112 Simon Sharon 70 Simon Thompson 60 91 94 101 108 Solange Milazzo 102 Sonia Facal 116 117 Soraya Gonzalez Rodriguez 116 117 Steen Hasselbalch 103 110

123 Name Page Number Stefan Wolf 73 Stéphanie Salmon 112 Stephen Dombrowski 76 Taichi Tsuji 64 Takaoki Kimura 72 Takashi Kato 109 Takeo Kato 89 Takuya Watanabe 107 Terje Sӕhle 81 Tetsuro Ishihara 48 61 95 Tetsuya Ohara 64 Thomas Marlow 57 Thoralf Knitter 71 Tiina Laiterä 109 Timo Sarajärvi 109 Tom Marlow 55 55 55 Tomas Radovnicky 115 Tomohisa Omura 77 87 Tomohisa Oomura 90 Tomoshi Osawa 49 Toru Baba 48 61 95 Toshiaki Miyati 49 66 Toshihiko Kuroiwa 77 87 90 Toshiki Saito 64 Tunehito Nakao 107 Ulrich-Wilhelm Thomale 72 Uwe Kehler 99 Valentina Galkowski 97 Valerie Vancollie 57 Vartan Kurtcuoglu 23 Vasiliy Danilin 103 Veit Rohde 72 73 Veronique Promelle 102 Véronique Quaglino 98 Victor Rodrigo 87 Victoria Wykes 102 Ville Leinonen 54 55 55 88 109 Vita Stagno 65 100 Wai Cheong Soon 69 Walter Hader 51 Wataru Narita 48 61 95 Weihong Yuan 73 William Bradley 48 23 William Singleton 50 Wisam Al-Faiadh 65 Xavier Leclercq 68 Yann Herault 57 Yasuhiko Hayashi 74 93 Yasuhiko Yamamoto 74 Yimin Shen 74 Yojiro Seki 86 Yoshihiro Urade 62 49 62 Yoshimi Takahashi 89 Yoshinaga Kajimoto 77 87 90 Yoshitaka Suzuki 64 Yoshiyuki Nishio 48 61 95 Yossi Porat 70 Yu Shimizu 74 Yue Gao 101 Yukiko Suzuki 111 Yutaka Hayashi 74 Yutaka Hayashi 93 Zofia Czosnyka 59 70 78

124 CME/CPD Accreditation

The Royal College of Surgeons of England has accredited the following events for CME/CPD points:

Normal Pressure Hydrocephalus Educational Symposium, 5th September 2014: up to 6 CME/CPD points.

IHIWG Meeting, 5th September 2014: up to 6 CME/CPD points.

Hydrocephalus 2014 International Conference: 6th -8th September 2014: up to 18 points.

The events are listed on the Royal College of Surgeons of England Accreditation Portal at http://accreditation.rcseng.ac.uk/ Home/InfoAccredited on the RCS website.

Delegates must complete feedback forms in order to obtain CME/CPD points”

125 UC201502153EE_ST_Ares Ad A4 cor1.indd 1 15/08/14 11:42 proGAV 2.0 ® In touch with you We understand the gravity of the situation.

Gravitational valves by Miethke

Invitation Luncheon Seminar: ® - “Miethke proGAV 2.0 Gravitational valve (r)evolution”

Monday 3rd September Old Council Chamber 12:30 -1:30 Gravitational valve (r)evolution

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