Brain-Degenerative: Intracranial Hypertension, Hypotension and CSF-Leaks Pedro Vilela Lisbon

16/04/18

Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks

Pedro Vilela Lisbon - Portugal

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • CSF pressure diseases:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

1 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

• CSF volume – Production: 0.35-0.6mL/min (500-600mL/day)

– Volume: 160 mL » ~25% à ventricles » ~75% à subarachnoid space (intracranial and spinal)

Background • CSF pressure – Similar to the ICP (intracranial pressure) – Fluctuates ( including during the day) » Monro-Kellie doctrine CSF and CBV have reciprocal changes in order to maintain a normal intracranial pressure (ICP)

– Varies: 60 - 250 mmH2O (280 mmH2O in children)

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

• CSF volume – Production: 0.35-0.6mL/min (500-600mL/day)

– Volume: 160 mL » ~25% à ventricles » ~75% à subarachnoid space (intracranial and spinal)

Background • CSF pressure – Similar to the ICP (intracranial pressure) Changes on the CSF volume will – Fluctuates ( including during the day) induce CBV variation at the » Monro-Kellie doctrine CSF and CBV have reciprocal changes in order to maintain venous side (since the veins a normal intracranial pressure (ICP) are more elastic / compressible – Varies: 60 - 250 mmH2O (280 mmH2O in children) and have lower pressure

2 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

• CSF opening pressure

– Hypertension: > 250 mm H2O (children

> 280 mm H2O)

– Hypotension: < 60 mm H2O (horizontal

Background or lateral decubitus; sitting)

» Aliquorrhoea (negative or non- measurable pressure)

» Sitting the patient there is an increase of the CSF pressure in normal patients à in intracranial hypotension the CSF

pressure maintains < 60 mmH2O From: Lancet Neurol 2015; 14: 655–68

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

Arterial flow ArterioVenous

(arterial+venous) flow Venous flow Background

From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018

3 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

Arterial flow ArterioVenous

(arterial+venous) flow Venous flow Background ArterioVenous (arterial+venous) flow

CSF flow

From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• CSF physiology and pressure measurements:

CSF and Cerebral flow are Arterial flow closely related:

CSF flow secondarily (and

passively) due to cerebral blood volume changes Venous flow Systole

Background à increase inflow due to arterial flow à Not immediately compensated by venous (out)flow (is delayed CSF flow 90-100ms) à Compensated by immediate CSF outflow

From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018

4 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial CSF pressure changes:

• Types: Low-pressure / High-pressure

• Clinical presentation: Headaches

• Causes: Idiopathic or Symptomatic (secondary)

Background – Idiopathic intracranial hypotension à CSF leak – Idiopathic intracranial hypertension à (?)

• If untreated à severe complications: – blindness (CSF hypertension) – coma (CSF hypo and hypertension)

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypertension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

5 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial CSF pressure changes: IC Hypertension • Causes: • Hydrocephalus

• Intracranial mass

• Brain “oedema”; Etiology toxic; inflammatory; infectious lesions

• Venous outflow obstruction

• Idiopathic From: Lancet Neurol 2015; 14: 655–68

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):

– Pseudotumor cerebri – Benign intracranial hypertension (... not always benign ...)

• Definition: – Chronic elevation of ICP » Headache + Papilledema + no localizing neurologic signs + normal CSF composition

Diagnostic criteria » No definable cause (no secondary cause of ICP increase) hydrocephalus, hypertensive encephalopathy / PRESS, mass lesion, traumatic brain injury, infection, ischemic stroke, venous outflow obstruction, venous thrombosis, metabolic/ drugs (hypoxemia, hypercapnia, hypervitaminosis A, acute liver failure,...), fever, seizures • Imaging: R/O secondary causes of intracranial hypertension

6 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):

Diagnostic criteria

From Friedman D et al Neurology 2013

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Diagnostic criteria

Headache Papilledema

High CSF opening pressure

Diagnostic criteria CSF normal

From: Lancet Neurol 2015; 14: 655–68

7 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children 2013

Diagnostic criteria

From Friedman D et al Neurology 2013

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):

• Hypotheses » Increase brain water content (and increase brain volume) » Excess CSF production » Reduced CSF absorption

» Increased intra abdominal/thoracic pressure (obesity) » Increase venous pressure

Etiology • Venous stenosis (seems to be secondary to increased ICP)

» Inflammatory / Immunologic • some cases CSF: presence of oligoclonal bands; increase cytokines » Cellular / molecular dysfunction: • Dysregulation of aquaporin 1 and 4 receptors • Dysregulation of mitochondria • Dysregulation of signaling leptins

8 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypertension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Prevalence

– Community-based: 1 per 100 000

– Gender: adults F > M (5-15 : 1) (men 10% of cases) » No gender predominance in prepubertal children – All ages (pediatric à elderly): Peak 3 rd decade of life (20-42 y/o) Prevalence – Increased prevalence » Female » Obesity (high BMI) – present > 70% of cases • BMI correlates with CSF opening pressure (? increased intra-abdominal/thoracic pressure)

» Sleep apnea » Vitamin A toxicity » Withdrawal of steroid therapy

9 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

• Idiopathic Intracranial hypertension (IIH):R

– Clinical presentation

• Severe headache (> 90% of cases) – Bilateral (mimics migraine) » Constant or fluctuating » Aggravates: Valsalva maneuver, coughing, bending over or lying (increases the intacranial pressure) • Visual complains (~50-75%) – Bilateral Papilloedema » blurred vision, photopsia, or transient visual obscuration L » absent in rare cases (specially in male gender) – IIH without

Clinical presentation papilloedema à more frequently associated with dural sinus stenosis – Optic nerve atrophy (bilateral) » associated to longstanding papilloedema • Other associated symptoms: » Diplopia (unilateral or bilateral VI cranial nerve palsy) » Pulsatile tinnitus » Nausea, vomiting (~50%) » Less common: neck or back pain, depression, mild cognitive impairment

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypertension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

10 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks – Imaging findings (MRI) from Hartmann AJP et al JCN 2016 – Dural sinus (transverse sinus) stenosis – superior to 50% -(~ 93-97%) – Eye

» Posterior globe flattening - (~ 45 - 98%) » Distention of the perioptic subarachnoid space – nerve sheath > 5.5 - 6mm (~ 45 - 89%) » Protrusion of the optic papillae (~ 3- 59%) » Enhancement / Bright DWI spot at the optic nerve head (~ 2 – 50%) – Empty (partially empty) sella (~ 80-83%) from Ducrus A et al Lancet N 2015

Imaging findings » protrusion of the subarachnoid space in the cavum sellae – Other » “Meningocele” and enlargement of Meckel cave, foramen ovale, » “Slit” ventricles » Tonsillar herniation

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks – Imaging findings (MRI) – Dural sinus (transverse sinus) stenosis – superior to 50% -(~ 93-97%) – Eye

Imaging findings » protrusion of the subarachnoid space in the cavum sellae – Other » “Meningocele” and enlargment of Meckel cave, foramen ovale, » “Slit” ventricles » Tonsillar herniation

from Tawfik K et al Oto&N 2017

11 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks – Imaging findings (MRI) – Dural sinus (transverse sinus) stenosis – superior to 50% -(~ 93-97%) – Eye

from Hartmann AJP et al JCN 2016

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Dural sinus stenosis – most frequent imaging sign - – Dural sinus stenosis is present in > 90% of cases (93 – 97% of patients) • Morris P 2018: IHH 94% Controls: 3%

• Farb R 2003: IHH 93% Controls: 6.7%

Controversial: cause or consequence of IIH (vicious cycle) • Physiopathology: dural sinus stenosis / thrombosis à impaired venous outflow à reduced CSF absorption à increased ICP • Dural sinus “stenosis” and hypoplasia (>50% of dural sinus length with reduced diameter) are frequent in asymptomatic population Imaging findings • IIH patient show reversibility of TSS “stenosis” after lumbar CSF drainage (functional stenosis) • No correlation: TSS grade and opening CSF pressure

TSS – transverse sinus stenosis (more common) • more common at the TS / SS junction • commonly bilateral stenosis (~ 85% of patients) • triangular shape (in opposition to the round sinus shape)

12 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):

• Dural sinus stenosis Classification:

Qualitative Score (Farb R 2003) 0 / GAP: discontinuity (gap) or aplastic segment;

hypoplasia or severe stenosis within a segment CCS 4 1 / <25%: Quantitative (CAD - Zur D 2017): higher of the conduit estimated as less than 25% of the cross sectional difference (IIH/C) on minimal cross section area diameter of the lumen of the distal superior sagittal sinus;

2 / 25-50%: moderately stenosed segment of the conduit CCS 3 (25–50%)

Imaging findings 3 / 50-75%: mildly narrowed segment (50–75%)

CCS 1 4 / >75%: no significant narrowing seen (75–100%)

Combined Conduit Score (CCS) = sum of the lowest scores

From Farb R et al Neurology 2003

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): 0 4 • Dural sinus stenosis

Qualitative Score (Farb R 2003)

2 Quantitative (CAD - Zur D 2017): higher 1 difference (IIH/C) on minimal cross section area

Imaging findings 1 2

1 1

From Farb R et al Neurology 2003

13 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):

• Dural sinus stenosis

Qualitative Score (Farb R 2003)

Quantitative (CAD - Zur D 2017): higher difference (IIH/C) on minimal cross section area

Imaging findings

From Zur et al Brain and behavior 2017

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypertension:

• Background • Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

14 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Treatment

• Weight loss (~0.5 Kg/week)

• Diet: fluid restriction and a low-sodium st 1 line • Acetazolamide • carbonic anhydrase inhibitor à reduces CSF production and Treatment ICP Conservative • 1–4 g per day (in 2 -3 doses) treatment and • Topiramate medical • weak carbonic anhydrase inhibitor àreduces CSF production and ICP treatment • 20 – 120 mg per day • No indication for steroids

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Treatment

• Bariatric surgery • weight-reduction surgery

• morbid obesity patients with failure weight-reduction with diet and exercise • CSF shunting procedures st • ventricular / lumbar CSF derivation (lumbar / ventricular peritoneal 2 line shunt) • refractory patients with severe headaches Treatment • Optic nerve sheath fenestration • compression of optic nerve by creation of a window into the dural sheath, done bilaterally or sequentially (the other eye might improve after the fi rst eye is operated on) Refractory • refractory patients with severe visual (and mild headaches) cases • Endovascular venous PTA & Stenting • PTA & Stenting of a stenotic venous sinus: bilateral or unilateral (in cases that have a contralateral hypoplasic sinus) • refractory patients with non-reversible (after lumbar puncture) transverse sinus stenosis; and/or refractory to other surgical treatments

15 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Treatment

• Papilloedema + severe headache + not Emergent severe visual loss à ventricular / lumbar CSF shunting Treatment Prevent visual • Papilloedema + severe visual lossà optic loss !!! nerve sheath fenestration

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Endovascular treatment:

– 1st published case: Higgins 2002

– Objectives:é venous outflow à ê venous pressure à é CSF outflow and absorption

– Indications:

Treatment » IHH with refractory persistent / progressive papilledema • Under conservative treatment diet + carbonic anhydrase inhibitors (or non- compliant or severe side effects with medical therapy) • After failed surgical procedures » Pressure gradient • Pressure gradient > 5mmHg favorable for stenting (absence of pressure gradient is not a contraindication for stenting • General anesthesia may macerate the pressure gradient (evaluated on awake / conscious sedation procedures)

16 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Endovascular treatment:

– Data » Puffer et al 2013 (meta analysis): 143 patients

» Aguilar-Pérez M et al 2017 (case series): 51 patients

• PTA & Stenting

Treatment • Headache improvement/resolution ~ 84- 88% failure ~12-16% • Papilledema improvement/resolution ~ 88-97% failure ~3-12% • Visual symptoms: improvement/resolution ~ 82-87% failure ~13-18%

• Long term follow up à retreatment ~12% • in stent stenosis: ~10 % • de novo stenosis: 14 %

Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks

Pedro Vilela Lisbon - Portugal

17 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial CSF pressure changes: IC Hypotension • Causes:

• Hypovolemia

• Overshunting Etiology • CSF leaks (traumatic and “spontaneous”)

From: Lancet Neurol 2015; 14: 655–68

18 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Cause: CSF leak – Traumatic (more common type) – 96% » Locationà skull base

» 80% trauma; 16% iatrogenic/postsurgical

Etiology – Spontaneous – 4% » Location à often at spine level; rarely from skull base • More common: cervico-thoracic junction; thoracic » Cause: unknown • Dural weakness: dural attenuation; dural tears; meningeal diverticula • Ventral CSF leaks à spinal degenerative diseases • Connective tissue diseases (Marfan S; Ehlers-Danlos S)

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Physiopathology: CSF leak

Loss of CSF Volume

Physiopathology Exponential relationship VOLUME – PRESSURE The withdrawal of approximately 10% of the CSF volume à cause > 40% decrease in the (already negative) vertex CSF pressure

Volume compensation: é Blood Vol Negative intracranial pressure Monroe-Kellie hypothesis: constant intracranial volume (blood+CSF+brain)

19 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Negative intracranial pressure

Descent (sagging) of the brain

Traction on Traction of pain nerve roots / Venous sensitive cranial rupture structures nerves Physiopathology Nerve Subdural Pain palsies hematomas

Encephalopathy; Loss of consciousness; Coma

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Volume compensation Negative intracranial pressure Monroe-Kellie hypothesis: constant intracranial volume (blood+CSF+brain)

Descent (sagging) of the brain Increase of the vascular component

Traction on Traction of pain nerve roots / Venous Venous Dilatation (intracranial & spinal) sensitive cranial rupture structures nerves Physiopathology Increased venous Dilatation of Nerve Subdural Pain pressure pain- palsies hematomas Pituitary sensitive hyperemia Dura has no BBB venous Encephalopathy; Loss of consciousness; structures Coma Extravasation of fluid through the innermost

dural layer Pain

Subdural collections

20 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: Low CSF volume headaches

• Not primary CSF low pressure but CSF low volume • Other terms: "CSF hypovolemia”;"CSF volume depletion”; "spontaneous CSF leaks”

• Prevalence – Community-based: 2-5 per 100 000 (more common than Idiopathic Intracranial Hypertension) Prevalence – Emergency service annual incidence 5 per 100 000 (~ SAH) – Probably under diagnosed

– Gender: F>M (2:1) – All ages (pediatric à elderly): Peak 4th decade of life (35-42 y/o)

21 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Clinical presentation • Severe headache

– Bilateral and Orthostatic » Starts ~15min after supine position and relieved after ~15-30 min of recumbence » sometimes preceded by cervical / interscapular pain; overtime the aggravation with orthostatic position may become less evident – Aggravates: Valsalva maneuver (increases the CSF outflow) – Thunderclap headache (15% of cases) – Not always bilateral and orthostatic: persistent, pulsatile, ect… headaches… even paradoxical postural headache sometimes may be encountered (headaches present in recumbence and relieved in an upright position) Clinical presentation • Other associated symptoms (orthostatic in nature): nausea, vomiting, anorexia, neck pain, dizziness, changes in hearing, galactorrhea, facial numbness or weakness, or radicular symptoms involving the upper limb

• Severe symptoms (rare): – Encephalopathy; Loss of consciousness; Coma Require emergent treatment à intratechal Saline

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: • Intracranial Hypotension complications: – Recurrence of IC hypotension episodes – Evolution to chronicity: chronic ( IC hypotension ) headache

– Other: » Venous thrombosis (~1% of cases) » Subdural hematomas à brain compression (unpredictable evolution, and may acutely increase in size) » Cerebral infarction (very rare) Complications

• CSF leaks complications: – Spinal leak: “No” risk for meningitis (complication) – CSF is absorbed by the epidural venous plexus – Skull base leak: risk for meningitis

22 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Diagnostic criteria

Headache Signs/symptoms of decrease IC pressure

Low CSF opening pressure Improvement after epidural blood patch

Diagnostic criteria

Abnormal MRI findings CSF leak demonstration

From: Lancet Neurol 2015; 14: 655–68

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

23 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: • Imaging evaluation: – 1st line studies: » Brain or Brain & Spine evaluation: MRI is superior to CT » CSF leak study: noninvasive method (MRI) – 2nd line studies: invasive studies for refractory cases (patients that failed 2 or 3 – non-oriented - lumbar epidural patches) Investigation • Imaging findings: – Primary: CSF leak detection » myeloCT » myeloMR » Other methods: Myelo-DSA; Nuclear medicine studies

– Secondary: intracranial and spinal changes

Brain-Degenerative: Intracranial hypertension,

– Secondary: intracranial and spinal changes

24 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Primary Imaging findings à detection of the CSF leak(s)

– Myelography (Myelo-CT) » Delayed acquisitions (3-4h) for slow/low volume leaks » Rapid acquisitions for fast/high volume leaks à DSA

Imaging findings – Myelo-MRI » Without contrast » With intratecal gadolinium

– Radionuclide myelo / cisternography

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: • Primary Imaging findings à detection of the CSF leak(s)

– Myelography (Myelo-CT) » Delayed acquisitions for slow/low volume leaks » Rapid acquisitions for fast/high volume leaks à DSA Imaging findings: CT / MRI

25 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: • Primary Imaging findings à detection of the CSF leak(s)

– Myelo-MR » Without contrast » With intratecal gadolinium (“off label”) Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Intrathecal gadolinium MRI myelography

• IT injection of Gd contrast is an off-label use • Reserved for highly selected patients – substantially symptomatic – have high clinical suspicion of CSF leak – have demonstrated no leak on NMC / CTM Fatsat coronal T1 after IC gadolinium (1 cc of gadobutrolum) Albes G et al. Detection and

Imaging findings: CT / MRI treatment of spinal CSF leaks in idiopathic intracranial hypotension. Neuroradiology 2012

26 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Causes

Dural diverticulum

osteophyte Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: Leak identification – Nuclear Medicine (radioisotope) Cisternography • IV injection of Indium-111 by lumbar puncture à serial scanning during 24-48 hours – Direct Sign: CSF leak demonstration – Indirect Signs: » Paucity of radioisotope at cerebral convexities: 24h à normally - isotope progresses into the cerebral convexities where it is absorbed by the arachnoid villi (in a CSF leak there is no passage to the cerebral convexities that leads to a deficiency of isotope à most common sign » Early passage (<4h compared to 6-24h) to urinary bladder/kidneys of the radioisotope

Imaging findings: Nuclear Medicine • Drawbacks: – variable sensitivity (60 – 90%); – False negatives: no active leak / leak smaller than image resolution – Low spatial resolution / Multiple scans / Duration of the study – Patient compliance and collaboration (difficult in outpatients)

27 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Nuclear Medicine (radioisotope) Cisternography Imaging findings: Nuclear Medicine

Indirect sign: absence/ Indirect sign: early passage to paucity of radioisotope over urinary bladder/kidneys of the CSF leak identification the cerebral convexities radioisotope

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Secondary Imaging findings à brain and spinal changes induced by the CSF leak(s) – CSF low volume / pressure

– Intracranial findings

Imaging findings: CT / MRI – Spinal findings

28 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings (SEEPS) – 5 major findings: • Sagging of the brain à ~ 50 – 72% • Subdural fluid collections à ~ 15 – 72% – Effusions “Hygromas” (common); hematomas • Diffuse dural meningeal Enhancement / thickening à ~ 85% • Venous Engorgement • Pituitary hyperemia Imaging findings: CT / MRI – MR Imaging may be normal à up to 20% of cases Absence of CT/MR imaging intracranial hypotension findings does not exclude the diagnosis!

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Negative intracranial pressure

Descent (sagging) of the brain

Traction on Traction of pain nerve roots / Venous sensitive cranial rupture structures nerves

Nerve Subdural Pain palsies hematomas Imaging findings: CT / MRI

• Effacement of perichiasmatic prepontine cisterns • Pituitary stalk and pons flattening • Bowing of the optic chiasm • Cerebellar tonsils descend

29 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Volume compensation Negative intracranial pressure Monroe-Kellie hypothesis: constant

intracranial volume (blood+CSF+brain)

Descent (sagging) of the brain Increase of the vascular component

Traction on Traction of Venous Dilation (intracranial & spinal) pain nerve roots / Venous sensitive cranial rupture structures nerves Increased venous Dilatation of pressure pain- Pituitary Nerve Subdural hyperemia Pain palsies hematomas sensitive

Imaging findings: CT / MRI Extravasation of fluid venous through the innermost structures • Effacement of perichiasmatic dural layer meningeal prepontine cisterns Pain vessels à • Pituitary stalk and pons flattening Subdural collections contrast • Bowing of the optic chiasm enhancement • Cerebellar tonsils descend

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

• Subdural Fluid Collections / Hematomas à 15 - 50% – Type: Effusions (70-90%); Hematomas (10-30%) à different etiology

• Effusions / “Hygromas” àSUB DURAL FLUID COLLECTIONS – Caused by the presence of a pressure gradient – Subdural effusions are typically thin, crescentic, and located either below or between enhancing membranes – Generally are not seen in the absence of dural enhancement – May be bilateral and are usually without mass effect – Resolve within days - weeks Imaging findings: CT / MRI

• Hematomas – Caused by the rupture of the bridging veins as the CSF volume decreases and the brain sags, pulling away from the dura – Typically have mass effect – Resolve with the correction of the SIH (require longer follow up – up to 3 months)

30 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks Subdural fluid collections

Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Clinical presentation

Subdural fluid collections Subdural hematomas Imaging findings: CT / MRI

from: Tana C et al; Neurology. 2014 Teaching NeuroImages: A dangerous complication of spontaneous intracranial hypotension.

31 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

• Diffuse dural thickening/enhancement (pachymeninges)à 85% – Diffuse / crescent-shaped dural thickening » Thin and Linear – not nodular » No leptomeningeal involvement » Supra and infratentorial – Isointense to brain on T1 & Hyperintense to brain on T2 / FLAIR – Diffuse intense contrast-enhancement

Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Imaging findings: CT / MRI

32 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

• Brain downward displacement à 40-50% – Sagging of the midbrain (descend below the level of the dorsum sellae) – Reduction of the cerebral peduncles / pons angle – Caudal displacement of the cerebellar tonsils (25-75%) – Temporal lobes herniation thought the incisura Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

SIH Post treatment Imaging findings: CT / MRI

33 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

• Other – Engorgement of the venous structures (cavernous sinus; other dural sinus; cortical veins; spinal veins – epidural plexuses) Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

SIH Post treatment Imaging findings: CT / MRI

34 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Secondary imaging findings à CT / MRI

• Other – Sella turcica: Enlargement of the pituitary gland (convex superior border) – reversible pituitary hyperemia

SIH Post treatment Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: Spinal Findings • Extra-arachnoid fluid collections

Cause unknown: direct leakage of CSF into the epidural space / effusion / transudation of intravascular fluid from hyperemic meninges into epidural / subdural space Nonfocal, extending over multiple spinal levels • Dural thickening and enhancement From dural vasodilation and engorgement • Dilation of the anterior epidural veins / venous plexus Imaging findings: CT / MRI

35 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks

Imaging findings: CT / MRI

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks 07-2009 10-2010

Imaging findings: CT / MRI

36 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension:

• Background • Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Treatment

Symptomatic treatment: Bed rest; oral hydration Positive 1st line NSAI

results ? Theophylline ? (without identified ? Caffeine (increase CSF production)? ~ 15-30% of CSF leak) ? Compressive abdominal binders ? ? Vitamin A ? cases

Treatment Refractory after ~1 week

Positive Epidural blood patch 2nd line results (non target) ~ 70% of cases

37 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Treatment: Epidural Blood Patch • Method: – Patient: decubitus or Trendelenburg position – Autologous blood injection at the epidural space » Location: • Single à lumbar • Double à lower lumbar and thoracolumbar junction » Volume: 10-80mL depending on the size of epidural space Treatment • 1st à low volume (10-20mL) • 2nd à higher volume (>20mL) – Followed by bed rest during 24h in decubitus • Complications: – Vasovagal syncope; lumbar pain, hypertension headaches (rebound), arachnoiditis, aseptic meningitis, infection

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Treatment

Epidural blood patch 2nd line

Refractory after ~ 5 days Treatment Repeated Epidural blood patch - non target 2nd line (2 to 3 times with an interval of 5 days)

Refractory after ~ 5 days

Other therapeutic options: precise site of the CSK leak 3rd line Target Blood patch / Fibrin sealant / Surgery

38 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension: – Treatment

Treatment

Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks

Pedro Vilela Lisbon - Portugal

39 16/04/18

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypotension (selected references)

• Headache arising from idiopathic changes in CSF pressure. Ducros A, Biousse V. Lancet Neurol. 2015 Jun;14(6): 655-68. • High-pressure headaches, low-pressure syndromes, and CSF leaks: diagnosis and management. Graff-Radford SB, Schievink WI. Headache. 2014 Feb;54(2):394-401

• Mokri B. Spontaneous CSF leaks: low CSF volume syndromes. Neurol Clin. 2014 May;32(2):397-422. • Spontaneous Low Pressure, Low CSF Volume Headaches Spontaneous CSF Leaks. Mokri, B et al; Headache. 2013;53(7):1034-1053. • Spontaneous Spinal Cerebrospinal Fluid Leaks and Intracranial Hypotension. Schievink, W JAMA 2006 • Intracranial Hypotension Syndrome: A Comprehensive Review. Paldino, M et al; Neurosurg Focus. 2003

References • Yuh EL, Dillon WP. Intracranial hypotension and intracranial hypertension. Neuroimaging Clin N Am. 2010 Nov; 20(4):597-617.

Brain-Degenerative: Intracranial hypertension,

hypotension and CSF-leaks • Intracranial hypertension (selected references)

• Friedman DI, Liu GT, Digre KB. Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children. Neurology. 2013 Sep 24;81(13):1159-65 • Bateman GA, Stevens SA, Stimpson J. A mathematical model of idiopathic intracranial hypertension incorporating increased arterial inflow and variable venous outflow collapsibility. J Neurosurg. 2009;110(3):446–56 • Capel C, Baroncini M, Gondry-Jouet C, Bouzerar R, Czosnyka M, Czosnyka Z, Balédent O. Cerebrospinal Fluid and

Cerebral Blood Flows in Idiopathic Intracranial Hypertension. Acta Neurochir Suppl. 2018 • Bidot S, Saindane AM, Peragallo JH, Bruce BB, Newman NJ, Biousse V. Brain Imaging in Idiopathic Intracranial Hypertension. J Neuroophthalmol. 2015 • Hartmann AJ, Soares BP, Bruce BB, Saindane AM, Newman NJ, Biousse V, Peragallo JH. Imaging Features of Idiopathic Intracranial Hypertension in Children. J Child Neurol. 2017 Jan;32(1):120-126. References • Zur D, Anconina R, Kesler A, Lublinsky S, Toledano R, Shelef I. Quantitative imaging biomarkers for dural sinus patterns in idiopathic intracranial hypertension. Brain Behav. 2017 Jan 3;7(2):e00613 • Farb RI, Vanek I, Scott JN, Mikulis DJ, Willinsky RA, Tomlinson G, terBrugge KG. Idiopathic intracranial hypertension: the prevalence and morphology of sinovenous stenosis. Neurology. 2003 May 13;60(9):1418-24 • Morris PP, Black DF, Port J, Campeau N. Transverse Sinus Stenosis Is the Most Sensitive MR Imaging Correlate of Idiopathic Intracranial Hypertension. AJNR Am J Neuroradiol. 2017 Mar;38(3):471-477 • Aguilar-Pérez M, Martinez-Moreno R, Kurre W, Wendl C, Bäzner H, Ganslandt O, Unsöld R, Henkes H. Endovascular treatment of idiopathic intracranial hypertension: retrospective analysis of immediate and long- term results in 51 patients. Neuroradiology. 2017 Mar;59(3):277-287. • Puffer RC, Mustafa W, Lanzino G. Venous sinus stenting for idiopathic intracranial hypertension: a review of the literature. J Neurointerv Surg. 2013 Sep 1;5(5):483-6.