LASIK Fast Facts
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Qualified/Nonqualified Medical Expenses Under Health FSA/HRA Or HSA
Qualified/Nonqualified Medical Expenses under Health FSA/HRA or HSA Below is a partial list of medical expenses that may be reimbursed through your FSA/HRA or HSA, including services incurred by you or your eligible dependents for the diagnosis, treatment or prevention of disease, or for the amounts you pay for transportation to get medical care. In general, deductions allowed for medical expenses on your federal income tax, according to the Internal Revenue Code Section 213 (d), may be reimbursed through your FSA/HRA or HSA. Some items might not be reimbursable under your particular health FSA or HRA if the FSA or HRA contains exclusions, restrictions, or other limitation or requirements. Consult your summary plan description (SPD) of the health FSA or HRA for guidance. If you have an HSA, you are responsible for determining whether an expense qualifies for a tax‐free distribution. Qualified Expenses (partial list) Acupuncture Insulin Alcoholism treatment Lactation consultant Ambulance Laser eye surgery, Lasik Artificial limbs Occlusal guards to prevent teeth grinding Artificial teeth Optometrist Bandages, elastic or for injured skin Organ donors Blood pressure monitoring device Orthodontia Blood sugar test kits and test strips Osteopath fees Breast Pumps Oxygen Chiropractor Prosthesis Cholesterol test kits Reading Glasses Contact lenses Stop‐smoking aids Crutches Telephone equipment to assist persons with Dental Services and procedures hearing or speech disabilities Dentures Television equipment to assist persons with Diabetic supplies -
(Usually Oxygen) Burn Reaction Adds Energy to Effect • Steel Typical
Reactive Fusion Cutting • When gas used reacts with gas (usually oxygen) burn reaction adds energy to effect • Steel typically 60% added energy • Titanium 90% added energy • However can reaction can chemically change the work face eg titanium gets brittle from oxygen • Cutting speed is increases with addition of oxygen Reactive Fusion Cutting Striations • Reactions create a burn front • Causes striations in material • Seen if the cut is slow Behavior of Materials for Laser Cutting • Generally break down by reflectivity and organic/inorganic Controlled Fracture and Scribing Controlled Fracture • Brittle materials vulnerable to thermal stress fracture • Heat volume: it expands, creates tensile stress • On cooling may crack • Crack continue in direction of hot spot • Mostly applies to insulators eg Sapphire, glass Scribing • Create a cut point in the material • Forms a local point for stress breakage • Use either a line of holes or grove Cold Cutting or Laser Dissociation • Uses Eximer (UV) lasers to cut without melting • UV photons 3.5 - 7.9 eV • Enough energy to break organic molecular bonds • eg C=H bond energy is 3.5 eV • Breaking the bonds causes the material to fall apart: disintigrates • Does not melt, chare or boil surface • eg ArF laser will create Ozone in air which shows the molecular effects Eximer Laser Dissociation • Done either with beam directly or by mask • Short Laser pulse absorbed in 10 micron depth • Breaks polymer bonds • Rapid rise in local pressure as dissociation • Mini explosions eject material Eximer Micromachining -
Main Types of Lasers Used for Manufacturing- Key Properties and Key Applications
Main Types of Lasers Used for Manufacturing- Key Properties and Key Applications Tom Kugler Fiber Systems Mgr. Laser Mechanisms, Inc. www.lasermech.com LME 2011 Topics • Laser Output Wavelengths • Laser Average Power • Laser Output Waveforms (Pulsing) • Laser Peak Power • Laser Beam Quality (Focusability) • Key Properties • Key Applications • Beam Delivery Styles 2 Tom Kugler- Laser Mechanisms Compared to standard light sources… • Laser Light is Collimated- the light rays are parallel to and diverge very slowly- they stay concentrated over long distances- that is a “laser beam” • Laser Light has high Power Density- parallel laser light has a power density in watts/cm2 that is over 1000 times that of ordinary incandescent light • Laser Light is Monochromatic- one color (wavelength) so optics are simplified and perform better • Laser light is highly Focusable- low divergence, small diameter beams, and monochromatic light mean the laser can be focused to a small focal point producing power densities at focus 1,000,000,000 times more than ordinary light. 3 Tom Kugler- Laser Mechanisms Laser Light • 100W of laser light focused to a diameter of 100um produces a power density of 1,270,000 Watts per square centimeter! 4 Tom Kugler- Laser Mechanisms Examples of Laser Types • Gas Lasers: Electrical Discharge in a Gas Mixture Excites Laser Action: – Carbon Dioxide (CO2) – Excimer (XeCl, KrF, ArF, XeF) • Light Pumped Solid State Lasers: Light from Lamps or Diodes Excites Ions in a Host Crystal or Glass: – Nd:YAG (Neodymium doped Yttrium Aluminum -
Fluency of Laser and Surgical Downtime, Loss of Fixation, As Factors Related to the Precision Refractive
112ARTIGO ORIGINAL Fluência do laser e tempo de parada cirúrgica, por perda de fixação, como fatores relacionados à precisão refracional Fluency of laser and surgical downtime, loss of fixation, as factors related to the precision refractive Abrahão da Rocha Lucena1, Newton Leitão de Andrade2, Descartes Rolim de Lucena3, Isabela Rocha Lucena4, Daniela Tavares Lucena5 RESUMO Objetivo: Avaliar a correlação da fluência e o tempo de parada transoperatória por perda de fixação, como fatores de hiper ou hipocorreções das ametropias pós-Lasik. Métodos: A idade variou entre 19 e 61 anos com média de 31,27 ± 9,99. O tempo mínimo de acompanhamento pós-operatório foi de 90 dias. Foram excluídos indivíduos com topografia corneana pré-operatória com ceratometria máxima maior que 46,5D ou presença de irregularidades; ceratometria média pós-operatória simulada menor que 36,0D; pupilas maiores que 6mm; paquimetria menor que 500 µm; miopia maior que -8,0DE, hipermetropia maior que +5,0DE e astigmatismo maior que -4,0DC. O laser utilizado foi o Esiris Schwind com Eye-Tracking de 350Hz e scanning spot de 0,8 mm. O microcerátomo utilizado foi o M2 da Moria com programação de 130µm de espessura. Resultados: A acuidade visual logMAR pré-operatória com correção variou de 0,40 a 0 com média de 0,23 ± 0,69; a pós-operatória sem correção foi de 0,40 a 0 com média de 0,30 ± 0,68. A mediana foi de 0 logMAR para os dois momentos (p=0,424). No equivalente esférico pré e pós-operatório, notou-se uma óbvia diferença (p< 0,0001), no pré-operatório com média de -4,09 ± 2,83 e o pós com média de -0,04 ± 0,38. -
Detection of Lead in Soil with Excimer Laser Fragmentation Fluorescence Spectroscopy (ELFFS)
Detection of Lead in Soil with Excimer Laser Fragmentation Fluorescence Spectroscopy (ELFFS) J. H. Choi1, C. J. Damm2, N. J. O’Donovan1, R. F. Sawyer1, C. P. Koshland2, and D. Lucas3† 1Mechanical Engineering Department, University of California, Berkeley, CA 94720 2Science & Technology Department, Sierra Nevada College, NV 89451 3School of Public Health, University of California, Berkeley, CA 94720 4Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720 Date: 2/2/04 † Corresponding Author [email protected] PH: (510) 486-7002 FAX: (510) 486-7303 Index Headings: Photofragmentation; Fluorescence; Photochemistry; Plasma; Lead. 1 ABSTRACT Excimer laser fragmentation fluorescence spectroscopy (ELFFS) is used to monitor lead in soil sample and investigate laser-solid interactions. Pure lead nitrate salt and soil doped with lead nitrate are photolyzed with 193 nm light from an ArF excimer at fluences from 0.4 to 4 J/cm2. Lead emission is observed at 357.2, 364.0, 368.3, 373.9 and 405.8 nm. Time-resolved data show the decay time of the lead emission at 405.8 nm grows with increasing fluence, and a plasma is formed above fluences of 2 J/cm2, where a strong continuum emission interferes with the analyte signal. Fluences below this threshold allow us to achieve a detection limit of approximately 200 ppm in soil. INTRODUCTION Lead (Pb) poisoning from environmental and occupational exposure remains one of the most common and preventable diseases. There are numerous serious and detrimental health effects from inhalation or ingestion of lead, including poisoning or even death in extreme circumstances1. Various in situ, real-time methods to measure heavy metals in soil have been developed as a replacement for conventional wet-chemistry techniques that require laborious and time consuming processes, such as preparation, dissolution, chelation, and ion exchange2,3. -
Laser Measurement in Medical Laser Service
Laser Measurement in Medical Laser Service By Dan Little, Technical Director, Laser Training Institute, Professional Medical Education Association, Inc. The global medical industry incorporates thousands of lasers into its arsenal of treatment tools. Wavelengths from UV to Far-Infrared are used for everything from Lasik eye surgery to cosmetic skin resurfacing. Visible wavelengths are used in dermatology and ophthalmology to target selective complementary color chromophores. Laser powers and energies are delivered through a wide range of fiber diameters, articulated arms, focusing handpieces, scanners, micromanipulators, and more. With all these variables, medical laser service personnel are faced with multiple measurement obstacles. At the Laser Training Institute (http://www.lasertraining.org), with headquarters in Columbus Ohio, we offer a week-long laser service school to medical service personnel. Four times a year, a new class learns the fundamental concepts of power and energy densities, absorption, optics, and, most of all, how lasers work. With a nice sampling of all the major types of medical lasers, the students learn hands-on calibration, alignment, and multiple service skills. Lasers used in the medical field fall under stricter safety regulations than other laser usages. Meeting ANSI compliances are critical to the continued legal operation of all medical and aesthetic facilities. Laser output powers and energies are to be checked on a semi-annual basis according to FDA Regulations and are supported by ANSI recommendations which state regular scheduled intervals. In our service school we exclusively use Ophir-Spiricon laser measurement Instrumentation. We present a graphically enhanced presentation on measurement technologies and the many, varying, critical parameters that are faced with not only each different type of laser but design differences between manufacturers. -
Laser Vision Correction: a Tutorial for Medical Students
Laser Vision Correction: A Tutorial for Medical Students Written by: Reid Turner, M4 Reviewed by: Anna Kitzmann, MD Illustrations by: Steve McGaughey, M4 November 29, 2011 1. Introduction Laser vision correction is the world’s most popular elective surgery with roughly 700,000 LASIK procedures performed in the U.S. each year (AAO, 2008). Since refractive errors affect half of the U.S. population 20 years of age and older, it comes as no surprise that many people are turning to laser vision correction to obtain improved vision (Vitale et al. 2008). Due to its popularity, medical students will inevitably be asked by patients, family, and friends about refractive eye surgery. It is important to have a basic understanding of laser vision correction, outcomes, and associated risks. The goal of laser vision correction is to decrease dependence on glasses and contact lenses by focusing light more effectively on the retina. While there are a number of different surgeries used to achieve this result, this tutorial will focus specifically on laser vision correction, which consists of laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). In the U.S., LASIK comprises about 85% of the laser vision correction market with PRK making up the other 15% (ISRS 2009). The cost of surgery varies in price from hundreds to thousands of dollars and is not covered by insurance, similar to cosmetic surgery. Laser vision correction is regarded as highly effective with studies showing 94% of patients achieving uncorrected visual acuity of 20/40 or better at 12 months (Salz et al. 2002), which is the visual acuity needed to drive without corrective lenses in most states. -
Ophthalmic Laser Therapy: Mechanisms and Applications
1 Ophthalmic Laser Therapy: Mechanisms and Applications Daniel Palanker Department of Ophthalmology and Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA Definition The term LASER is an abbreviation which stands for Light Amplification by Stimulated Emission of Radiation. The laser is a source of coherent, directional, monochromatic light that can be precisely focused into a small spot. The laser is a very useful tool for a wide variety of clinical diagnostic and therapeutic procedures. Principles of Light Emission by Lasers Molecules are made up of atoms, which are composed of a positively charged nucleus and negatively charged electrons orbiting it at various energy levels. Light is composed of individual packets of energy, called photons. Electrons can jump from one orbit to another by either, absorbing energy and moving to a higher level (excited state), or emitting energy and transitioning to a lower level. Such transitions can be accompanied by absorption or spontaneous emission of a photon. “Stimulated Emission” is a process in which photon emission is stimulated by interaction of an atom in excited state with a passing photon. The photon emitted by the atom in this process will have the same phase, direction of propagation and wavelength as the “stimulating photon”. The “stimulating photon” does not lose energy during this interaction- it simply causes the emission and continues on, as illustrated in Figure 1. Figure 1: LASER: Light Amplification by Stimulated Emission of Radiation For such stimulated emission to occur more frequently than absorption (and hence result in light amplification), the optical material should have more atoms in excited state than in a lower state. -
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). -
Slitlamp, Specular, and Light Microscopic Findings of Human Donor Corneas After Laser-Assisted in Situ Keratomileusis
CLINICAL SCIENCES Slitlamp, Specular, and Light Microscopic Findings of Human Donor Corneas After Laser-assisted In Situ Keratomileusis V. Vinod Mootha, MD; Dan Dawson, MD; Amit Kumar, MD; Joel Gleiser, MD; Clifford Qualls, PhD; Daniel M. Albert, MD Objective: To examine slitlamp, specular, and light mi- slitlamp examination, of which 3 were confirmed by his- croscopic features of human donor corneas known to have topathologic examination. Highly reflective particles were undergone laser-assisted in situ keratomileusis (LASIK). seen by specular microscopy in the stroma of 23 (88%) of 26 LASIK donor corneas, but only 1 (4%) of 26 con- Methods: Twenty-six donor corneas known to have un- trol donor corneas had a single highly reflective particle dergone LASIK prospectively underwent slitlamp exami- in the stroma (PϽ.001). The mean central endothelial nation with particular attention to the presence of a flap cell counts were similar: 2138 cells/mm2 in the LASIK edge, as well as specular microscopy with particular at- group compared with 2250 cells/mm2 in the controls tention to the presence of highly reflective particles in (P=.39). Vacuolization and pyknosis of keratocytes the stroma corresponding to the LASIK interface. Cen- was a consistent histopathologic finding after LASIK. tral endothelial cell density and pachymetery were ob- Metallic particles at the interface were not detected by tained. They were compared with 26 control donor cor- histology. neas without LASIK. Eleven LASIK donor corneas were processed for histology. Twenty-six donor corneas with Conclusions: Detection of a flap edge by slitlamp ex- no known prior keratorefractive surgery also under- amination may detect at least half of the donor corneas went similar slitlamp examination and specular micros- that may have undergone LASIK. -
Ifs® Advanced Femtosecond Laser Specifications for Site Preparation/Installation
iFS® Advanced Femtosecond Laser Specifications For Site Preparation/Installation Recommended Room Requirements • Minimum requirement: 10 ft x 10 ft (3048 mm x 3048 mm) • Ambient temperature: 67° F to 73° F (19° C to 23° C) (stable 24 hours a day) • Humidity requirement: Relative humidity between 35% to 65% (non-condensing) • The line voltage should be tested upon installation to ensure proper operation and should not vary by more than ± 10 % from nominal • Line Condition Max Current 120 VAC, 60 Hz 7 A 100 VAC, 50 Hz to 60 Hz 10 A 220-240 VAC, 50 Hz to 60 Hz 4 A o Dedicated AC line required prior to system installation (Laser UPS on electrical line connected to one breaker at panel) • Independent thermostat, controlling laser room only, required prior to system installation • High-speed Internet connection with static IP address required prior to system installation Delivery system shown in the retracted position. INDICATION: The iFS® Laser is a precise ophthalmic surgical laser indicated for use in patients undergoing surgery or other treatment requiring initial lamellar resection of the cornea. System Specifications Hardware Components • Dimensions and Weight: o Height: 60 in (152 cm) o Width: 47 in (119 cm) o Length: 41 in (104 cm) o Weight: 865 lbs (392 kg) • Laser Type: Mode-locked, diode-pumped Nd: glass oscillator with a diode-pumped regenerative amplifier • Pulse Repetition Rate: 150 kHz • Laser Pulse Duration: 600 fs to 800 fs (±50 fs) • Maximum Laser Pulse Peak Power: 4.2 mW (±0.8 mW) • Central Laser Wavelength: 1053 nm • Remote -
PRL™. Una Alternativa Al LASIK
ARCH. SOC. CANAR. OFTAL., 2002; 13: 27-31 ARTÍCULO ORIGINAL PRL™. Una alternativa al LASIK PRL™. An alternative to LASIK AMIGÓ RODRÍGUEZ A1, HERRERA PIÑERO R2, MUIÑOS GÓMEZ-CAMACHO JA2 RESUMEN Objetivo: Estudiar los resultados iniciales de la Lente Fáquica Refractiva (PRL™) implantada en pacientes miopes no susceptibles de ser corregidos mediante LASIK. Material y Métodos: A pacientes con miopía, con o sin astigmatismo, en los que existían con- traindicaciones para el LASIK y que cumplían con los criterios de inclusión, se les ofreció como alternativa la PRL™. Se analiza la dificultad técnica y las complicaciones per y pos- toperatorias así como los resultados visuales al mes evaluando el defecto refractivo previo, la exactitud en el cálculo de la potencia de la PRL™, la mejor agudeza visual (MAV) pre- operatoria, la AV obtenida sin corrección y la MAV postoperatoria. Resultados: Se implantó una PRL™ en 12 ojos de 7 pacientes. La dificultad técnica fue baja y no se presentaron otras complicaciones que edema corneal en 2 casos e iritis leve en otros 2 que cedieron en la primera semana. El defecto refractivo previo medio fue de –13,00 D (–9,50 / –16,00), el defecto refractivo postoperatorio medio fue –0,06 ± 0,6D (–1,25 / 0,87), la MAV preoperatoria se mantuvo en 1 caso, mejoró 1 línea en 5, 2 líneas en 4, 3 o más líneas en otros 2 casos. En ningún caso hubo pérdida de MAV preoperatoria. Conclusiones: Los resultados iniciales con la PRL™ nos revelan que es técnicamente sencilla de implantar y muy bien tolerada. El cálculo de potencia es muy bueno y los resultados visuales sobresalientes, mejorando en el 84% de los casos la mejor agudeza visual preope- ratoria.