MRI-Guided Laser Ablation Surgery for Epilepsy
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FY20 National Laser Users' Facility Program
FY20 NATIONAL LASER USERS’ FACILITY PROGRAM FY20 National Laser Users’ Facility Program M. S. Wei Laboratory for Laser Energetics, University of Rochester During FY19, the National Nuclear Security Administration (NNSA) and Office of Science jointly completed a funding opportu- nity announcement (FOA), review, and selection process for National Laser Users’ Facility (NLUF) experiments to be conducted at the Omega Facility during FY20 and FY21. After peer review by an independent proposal review committee for scientific and technical merit and the feasibility review by the Omega Facility team, NNSA selected 11 proposals for funding and Omega shot allocation with a total of 22.5 and 23.5 shot days for experiments in FY20 and FY21, respectively. During the first half of the FY20, LLE completed a one-time solicitation, review, and selection process for Academic and Industrial Basic Science (AIBS) experiments to utilize the remaining NLUF shot allocation in FY20–FY21. Ten new projects were selected for AIBS shot alloca- tion (a total of 11 and 10 shot days) for experiments staring in Q3FY20 and throughout FY21. FY20 was the first of a two-year period of performance for these 21 NLUF including AIBS projects (Table I). Fifteen NLUF and AIBS projects obtained a total of 232 target shots during FY20, which are summarized in this section. A critical part of the NNSA-supported NLUF program and the DOE Office of Fusion Energy Sciences (FES)-supported Laser- NetUS program is the education and training of graduate students in high-energy-density (HED) physics. In addition, graduate students can also access the Omega Laser Facility to conduct their theses research through collaborations with national labora- tories and LLE. -
Soft Tissue Laser Dentistry and Oral Surgery Peter Vitruk, Phd
Soft Tissue Laser Dentistry and Oral Surgery Peter Vitruk, PhD Introduction The “sound scientific basis and proven efficacy in order to ensure public safety” is one of the main eligibility requirements of the ADA CERP Recognition Standards and Procedures [1]. The outdated Laser Dentistry Curriculum Guidelines [2] from early 1990s is in need of an upgrade with respect to several important laser-tissue interaction concepts such as Absorption Spectra and Hot Glass Tip. This position statement of The American Board of Laser Surgery (ABLS) on soft tissue dentistry and oral surgery is written and approved by the ABLS’s Board of Directors. It focuses on soft tissue ablation and coagulation science as it relates to both (1) photo-thermal laser-tissue interaction, and (2) thermo-mechanical interaction of the hot glass tip with the tissue. Laser Wavelengths and Soft Tissue Chromophores Currently, the lasers that are practically available to clinical dentistry operate in three regions of the electromagnetic spectrum: near-infrared (near-IR) around 1,000 nm, i.e. diode lasers at 808, 810, 940, 970, 980, and 1,064 nm and Nd:YAG laser at 1,064 nm; mid-infrared (mid-IR) around 3,000 nm, i.e. erbium lasers at 2,780 nm and 2,940 nm; and infrared (IR) around 10,000 nm, i.e. CO2 lasers at 9,300 and 10,600 nm. The primary chromophores for ablation and coagulation of oral soft tissue are hemoglobin, oxyhemoglobin, melanin, and water [3]. These four chromophores are also distributed spatially within oral tissue. Water and melanin, for example, reside in the 100-300 µm-thick epithelium [4], while water, hemoglobin, and oxyhemoglobin reside in sub-epithelium (lamina propria and submucosa) [5], as illustrated in Figure 1. -
A Programmable Mode-Locked Fiber Laser Using Phase-Only Pulse Shaping and the Genetic Algorithm
hv photonics Article A Programmable Mode-Locked Fiber Laser Using Phase-Only Pulse Shaping and the Genetic Algorithm Abdullah S. Karar 1,* , Raymond Ghandour 1 , Ibrahim Mahariq 1 , Shadi A. Alboon 1,2, Issam Maaz 1, Bilel Neji 1 and Julien Moussa H. Barakat 1 1 College of Engineering and Technology, American University of the Middle East, Kuwait; [email protected] (R.G.); [email protected] (I.M.); [email protected] (S.A.A.); [email protected] (I.M.); [email protected] (B.N.); [email protected] (J.M.H.B.) 2 Electronics Engineering Department, Hijjawi Faculty for Engineering Technology, Yarmouk University, Irbid 21163, Jordan * Correspondence: [email protected] Received: 24 July 2020; Accepted: 2 September 2020; Published: 4 September 2020 Abstract: A novel, programmable, mode-locked fiber laser design is presented and numerically demonstrated. The laser programmability is enabled by an intracavity optical phase-only pulse shaper, which utilizes the same linearly chirped fiber Bragg grating (LC-FBG) from its two opposite ends to perform real-time optical Fourier transformation. A binary bit-pattern generator (BPG) operating at 20-Gb/s and producing a periodic sequence of 32 bits every 1.6 ns, is subsequently used to drive an optical phase modulator inside the laser cavity. Simulation results indicate stable programmable intensity profiles for each optimized user defined 32 code words. The laser operated in the self-similar mode-locking regime, enabling wave-breaking free operation. The programmable 32 bit code word targeting a specific intensity profile was determined using 100 generations of the genetic algorithm. -
MRI-Guided Laser Ablation Surgery of Hypothalamic Hamartomas
NEUROSURGERY MRI-Guided Laser Ablation Surgery of Hypothalamic Hamartomas HOW DOES THE TEAM DECIDE IF A PATIENT IS A CANDIDATE FOR MRI-GUIDED LASER ABLATION? A careful review of each patient’s medical records is the first step, including MR imaging of the brain and any applicable neurology or neurosurgery records. Patients with Hypothalamic Hamartomas (HH) typically have gelastic seizures, which are characterized by emotionless laughing, although variations including abnormal movements or staring spells are also common. Every patient’s case is handled individually, and it may be necessary for a patient to come to Texas Children’s Hospital for further testing to determine if they are a candidate for MRI-guided laser ablation surgery. WHAT HAPPENS DURING MRI-GUIDED LASER ABLATION SURGERY? After being placed under general anesthesia, a head frame, or a set of markers, is fitted to the patient’s skull. A CT scan is completed to orient the brain to the frame in 3 dimensions. With the help of computer software, a safe pathway that goes through the brain to the HH is calculated for the laser. The neurosurgeon then makes a small incision and drills a small hole through the skull (3.2 mm wide). The laser applicator, a small tube about the width of a strand of spaghetti, is inserted and guided through the brain into the HH. Once the laser applicator is inserted into the brain, the head frame is removed, and the patient is transported to the MRI scanner. After confirming proper placement of the laser applicator and setting safety markers, the surgeon performs a small test firing using the laser. -
Cutaneous Laser Surgery
Cutaneous Laser Surgery Vineet Mishra, M.D. Director of Mohs Surgery & Procedural Dermatology Assistant Professor of Dermatology University of Texas Health Science Center – San Antonio Visible-Infrared Range What does it stand for? LASER 3 Components: – L Light – Pumping system – A Amplification . Energy source/power supply – S Stimulated – Lasing medium – E Emission – Optical cavity – R Radiation Lasing Medium Supplies electrons for the stimulated emission of radiation Determines wavelength of laser – Expressed in nm 3 Mediums: – Gaseous (CO2, argon, copper vapor) – Solid (diode, ruby, Neodymium:Yag) – Liquid (tunable dye, pulse dye) Laser vs. IPL LASER – coherent, monochromatic light IPL = intense pulsed light – non coherent light – 515‐1000nm Monochromatc Laser light is a single color – color = specific wavelength of each laser Wavelength Wavelength determines – Chromophore specificity . Chromophore = tissue target that absorbs a specific wavelength of light – Depth pulse travels Chromophore & Absorption Spectra Chromophore/Target Wavelength Abs. Spectra – Hemoglobin – Blue-green and yellow light – DNA, RNA, protein – UV light – Melanin – Ultraviolet > Visible >> near IR – Black ink tattoo – Visible and IR – Water – IR Absorption Curves Terms to Know Energy – Joules, the capacity to do work Power – Rate of energy delivery (Watts = J/sec) Fluence – Energy density (J/cm2) Thermal Relaxation Time (TRT) – time required for an object to lose 50% of its absorbed heat (cooling time) to surrounding tissues Thermal Relaxation Time Thermal Relaxation Time (TRT) – time required for an object to lose 50% of its absorbed heat (cooling time) to surrounding tissues – directly proportional to size of an object (proportional to square of its size) – smaller objects cool faster (shorter TRT) than larger ones (longer TRT) Selective Photothermolysis by Anderson and Parrish (Science, 1983) Selective Photothermolysis – Thermocoagulation of specific tissue target with minimum damage to surrounding tissue Requirements: – 1. -
Experts Describe the Gold Standard in Medical
Christopher Zachary, MBBS, FRCP Experts describe the gold standard in Professor and Chair Department of Dermatology medical and aesthetic laser therapy, University of California-Irvine sharing their experiences using clinically- effective, time-proven technologies. asers have without question revolutionized the practice Expanding the Level of Service and ® of dermatology, permitting clinicians to treat conditions Patient Satisfaction with Gemini for which no medical therapies exist or offering results Efficient Management of Rosacea and Photodamage that exceed those of conventional therapeutics. From with the Gemini Laser medical conditions like acne and rosacea to cosmetic Lrejuvenation, laser systems can address a variety of the most Photorejuvenation in Asian Skin Tones: common presentations that bring patients to the dermatolo- Role of the Gemini Laser gist’s office. Gemini for Photorejuvenation: Given their remarkable utility, well-designed and manufac- A Cornerstone of the Cosmetic Practice tured lasers can be a tremendous asset to dermatologists. Yet, often physicians are overwhelmed by the prospect of incorpo- Targeting Patients’ Aesthetic Goals with the VariLite™ rating laser procedures into practice. Technology is costly, and there may be a tremendous sense of pressure to attract The VariLite for Fundamental Cosmetic Applications patients and, as important, provide treatment that meets their VariLite: A Reliable, Predictable Tool for Vascular and goals. There may also be a learning curve, as residency pro- Pigmented Lesions grams currently offer little training in aesthetic dermatology, Continued on page 3 Expert Contributors William Baugh, MD C. William Hanke, MD, MPH Assistant Clinical Professor, Visiting Professor of Dermatology, Western School of Medicine University of Iowa, Carver College of Medicine Medical Director Clinical Professor of Otolaryngology Head and Full Spectrum Dermatology, Neck Surgery, Fullerton, CA Indiana University School of Medicine Carmel, IN Henry H. -
A Practical Comparison of Ipls and the Copper Bromide Laser for Photorejuvenation, Acne and the Treatment of Vascular & Pigmented Lesions
A practical comparison of IPLs and the Copper Bromide Laser for photorejuvenation, acne and the treatment of vascular & pigmented lesions. Authors: Peter Davis, Adelaide, Australia, Godfrey Town, Laser Protection Adviser, Haywards Heath, United Kingdom Abstract: The recent rapid growth in demand for non-invasive light-based cosmetic treatments such as removal of unwanted facial and body hair, skin rejuvenation, removal of age-related and sun induced blemishes including pigment and vascular lesions as well as lines and wrinkles has led to a boom in the sale of medical devices that claim to treat these conditions. The often onerous safety regulations governing the sale and use of Class 4 lasers has contributed disproportionately to the popularity of similarly powerful non-laser Intense Pulse Light sources (“IPL”), particularly in the salon and spa sector. The practical science-based comparisons made in this review and the well- documented case studies in peer reviewed literature show that single treatment success in eradicating vascular and pigmented lesions may only be achieved by high fluence, wavelength-specific laser treatment and without the need for skin cooling. Introduction: hair removal with IPL The recent success of IPL in delaying hair re-growth (“hair management”) and permanent hair reduction (“photo-waxing”) is dependant upon using high energy settings for the former and is thought to work primarily because melanin absorbs energy across a wide spectrum of wavelengths. Cumulatively enough energy is absorbed to damage the hair follicle. It is also suggested that the longer wavelengths absorbed by blood and tissue water may also collectively damage hair follicle support structures such as the blood supply to the hair bulb aided by the overall temperature rise in the adjacent tissue. -
Second Harmonic Generation Microscopy: a Tool for Quantitative Analysis of Tissues
Chapter 5 Second Harmonic Generation Microscopy: A Tool for Quantitative Analysis of Tissues Juan M. Bueno, Francisco J. Ávila, and Pablo Artal Additional information is available at the end of the chapter http://dx.doi.org/10.5772/63493 Abstract Second harmonic generation (SHG) is a second‐order non‐linear optical process produced in birefringent crystals or in biological tissues with non‐centrosymmetric structure such as collagen or microtubules structures. SHG signal originates from two excitation photons which interact with the material and are “reconverted” to form a new emitted photon with half of wavelength. Although theoretically predicted by Maria Göpert‐Mayer in 1930s, the experimental SHG demonstration arrived with the invention of the laser in the 1960s. SHG was first obtained in ruby by using a high excitation oscillator. After that starting point, the harmonic generation reached an increasing interest and importance, based on its applications to characterize biological tissues using multiphoton microscopes. In particular, collagen has been one of the most often analyzed structures since it provides an efficient SHG signal. In late 1970s, it was discovered that SHG signal took place in three‐dimensional optical interaction at the focal point of a microscope objective with high numerical aperture. This finding allowed researchers to develop microscopes with 3D submicron resolution and an in depth analysis of biological specimens. Since SHG is a polarization‐sensitive non‐linear optical process, the implementation of polarization into multiphoton microscopes has allowed the study of both molecular architecture and fibrilar distribution of type‐I collagen fibers. The analysis of collagen‐based structures is particularly interesting since they represent 80% of the connective tissue of the human body. -
Low-Level Laser Therapy in Acute Pain: a Systematic Review of Possible Mechanisms of Action and Clinical Effects in Randomized Placebo-Controlled Trials
14258c08.PGS 6/8/06 2:20 PM Page 158 Photomedicine and Laser Surgery Volume 24, Number 2, 2006 © Mary Ann Liebert, Inc. Pp. 158–168 Low-Level Laser Therapy in Acute Pain: A Systematic Review of Possible Mechanisms of Action and Clinical Effects in Randomized Placebo-Controlled Trials JAN MAGNUS BJORDAL, P.T., Ph.D.,1 MARK I. JOHNSON, Ph.D.,2 VEGARD IVERSEN, Ph.D.3 FLAVIO AIMBIRE, M.SC.,4 and RODRIGO ALVARO BRANDAO LOPES-MARTINS, M.Pharmacol., Ph.D.5 ABSTRACT Objective: The aim of this study was to review the biological and clinical short-term effects of low-level laser ther- apy (LLLT) in acute pain from soft-tissue injury. Background Data: It is unclear if and how LLLT can reduce acute pain. Methods: Literature search of (i) controlled laboratory trials investigating potential biological mecha- nisms for pain relief and (ii) randomized placebo-controlled clinical trials which measure outcomes within the first 7 days after acute soft-tissue injury. Results: There is strong evidence from 19 out of 22 controlled laboratory studies that LLLT can modulate inflammatory pain by reducing levels of biochemical markers (PGE2, mRNA Cox 2, IL-1, TNF␣), neutrophil cell influx, oxidative stress, and formation of edema and hemorrhage in a dose- dependent manner (median dose 7.5 J/cm2, range 0.3–19 J/cm2). Four comparisons with non-steroidal anti-in- flammatory drugs (NSAIDs) in animal studies found optimal doses of LLLT and NSAIDs to be equally effective. Seven randomized placebo-controlled trials found no significant results after irradiating only a single point on the skin overlying the site of injury, or after using a total energy dose below 5 Joules. -
D'évaluation Des Technologies De La Santé Du Québec
(CETS 2000-2 RE) Report – June 2000 A STATE-OF-KNOWLEDGE UPDATE THE EXCIMER LASER IN OPHTHALMOLOGY: Conseil d’Évaluation des Technologies de la Santé du Québec Report submitted to the Minister of Research, Science And Technology of Québec Conseil d’évaluation des technologies de la santé du Québec Information concerning this report or any other report published by the Conseil d'évaluation des tech- nologies de la santé can be obtained by contacting AÉTMIS. On June 28, 2000 was created the Agence d’évaluation des technologies et des modes d’intervention en santé (AÉTMIS) which took over from the Conseil d’évaluation des technologies de la santé. Agence d’évaluation des technologies et des modes d’intervention en santé 2021, avenue Union, Bureau 1040 Montréal (Québec) H3A 2S9 Telephone: (514) 873-2563 Fax: (514) 873-1369 E-mail: [email protected] Web site address: http://www.aetmis.gouv.qc.ca Legal deposit - Bibliothèque nationale du Québec, 2001 - National Library of Canada ISBN 2-550-37028-7 How to cite this report : Conseil d’évaluation des technologies de la santé du Québec. The excimer laser in ophtalmology: A state- of-knowledge update (CÉTS 2000-2 RE). Montréal: CÉTS, 2000, xi- 103 p Conseil d’évaluation des technologies de la santé du Québec THE EXCIMER LASER IN OPHTHALMOLOGY: A MANDATE STATE-OF-KNOWLEDGE UPDATE To promote and support health technology assessment, In May 1997, the Conseil d’évaluation des technologies de disseminate the results of the assessments and la santé du Québec (CETS) published a report dealing spe- encourage their use in decision making by all cifically with excimer laser photorefractive keratectomy stakeholders involved in the diffusion of these (PRK). -
Abls Study Guide
______________________________________ Excerpts from the ABLS STUDY GUIDE (The complete Study Guide is used as part of the ABLS Certification process. These excerpts are for use in certain seminars and courses on medical lasers that the ABLS may be associated with, but is not a substitute for the actual ABLS Certification process. Information about the Board’s Certification is available at the ABLS website: www.americanboardoflasersurgery.org) _____________________________________ © The American Board of Laser Surgery Inc., 2016. All Rights Reserved. No part of these Study Guide Excerpts may be reproduced in any form without the express written consent of the ABLS. © The American Board of Laser Surgery Inc., 2016. All Rights Reserved. 1 Introduction ---- CHAPTER 1 Fundamentals of Laser Physics, Optics and Operating Characteristics for the Clinician ---- CHAPTER 2 Surgical Delivery Systems ---- CHAPTER 3 Laser Biophysics, Tissue Interaction, Power Density and Ablative Resurfacing of Human Skin: Essential Foundations for Laser Dermatology and Cosmetic Procedures ---- CHAPTER 4 Commentary on Ethics in Cosmetic Laser Surgery ---- CHAPTER 5 Safe Use of Lasers in Surgery ---- CHAPTER 6 Considerations in the Selection of Equipment © The American Board of Laser Surgery Inc., 2016. All Rights Reserved. 2 Contents and Topics in the Study Chapter 4 5 Materials : Commentary on Ethics in Cosmetic Laser Surgery (key considerations in providing Coptihamptuemr 5patient care). The study material consists of the proprietary ABLS Study Guide on fundamental laser science, : The Safe Use of Lasers in Surgery Fordelivery cosmetic systems, practitioners biophysics/ only tissue interaction, (oriented to the needs of the actual practitioner ethics, laser safety, and equipment selection. aCsh oappopterse d6 t:o support personnel) it also includes several chaptersLasers from and two Lights: excellent Procedures books on in a Considerations in the Selection broad range of cosmeticnd laser and light Cosmetic Dermatology, 2 Ed. -
With Short Pulse • About 7% Coupling Significantly Less Than the Osaka Experiment
Electron/proton generation from solid targets and applications Farhat Beg University of California, San Diego This work was performed under the auspices of the U.S. DOE under contracts No.DE-FG02-05ER54834, DE-FC0204ER54789 and DE-AC52-07NA27344. We greatly acknowledge support of Institute for Laser Science Applications, LLNL. Committee on Atomic, Molecular and Optical Sciences Meeting The National Academy of Sciences Washington DC, April 5, 2011 1 Summary ü Short pulse high intensity laser solid interactions create matter under extreme conditions and generate a variety of energetic particles. ü There are a number of applications from fusion to low energy nuclear reactions. 10 ns ü Fast Ignition Inertial Confinement Fusion is one application that promises high gain fusion. ü Experiments have been encouraging but point towards complex issues than previously anticipated. ü Recent, short pulse high intensity laser matter experiments show that low coupling could be due to: - prepulse - electron source divergence. ü Experiments on fast ignition show proton focusing spot is adequate for FI. However, conversion efficiency has to be increased. 2 Outline § Short Pulse High Intensity Laser Solid Interaction - New Frontiers § Extreme conditions with a short pulse laser § Applications § Fast Ignition - Progress - Current status § Summary Progress in laser technology 10 9 2000 Relativistic ions 8 Nonlinearity of 10 Vacuum ) Multi-GeV elecs. V 7 1990 Fast Ignition e 10 ( e +e- Production y 6 Weapons Physics g 10 Nuclear reactions r e 5 Relativistic