Upper gastrointestinal malignancy: palliation with thermal laser, photodynamic therapy and argon beamer
David Westaby, Martin Lombard in Therapeutic Gastrointestinal Endoscopy A problem-oriented approach, 2019
The major consideration for many Units will be the initial capital outlay and subsequent running costs of thermal lasers, dye lasers or APC. A Nd-YAG laser costs £50 000 to £60 000 and a diode laser in excess of £45 000, though this is likely to drop significantly as diode technology rapidly advances. Dye lasers vary widely in price, between £45 000 to £70 000, and combined thermal/dye laser instruments are available at about £90 000. If these expensive instruments are placed in a central location and used in other specialties, e.g. thoracic medicine, urology, gynaecology and surgery, then the expense can more readily be justified. As photodynamic therapy establishes and extends its role in oesophageal cancer palliation, serious consideration should be given to the acquisition of one of the recently developed multi-wavelength capability non-laser light sources which are likely to be priced at about £10 000. Although styled as (readily) tunable, most dye lasers operate at a narrow band wavelength, whereas the non-laser instruments have the facility of rapid replacement of a filter to provide light wavelength for a wide range of photosensitizers.
Lasers in Medicine: Healing with Light
Suzanne Amador Kane, Boris A. Gelman in Introduction to Physics in Modern Medicine, 2020
The active medium need not be a gas. Examples of lasers with solid active media are diode lasers, used in various medical applications, compact disc players, and supermarket scanner devices. Glasses such as neodymium-yttrium-aluminum-garnet (abbreviated Nd:YAG and pronounced “neodymium yag”), erbium:YAG, and holmium:YAG are used to make especially versatile, high-power lasers. The Nd:YAG laser can be operated at one of three wavelengths: the infrared (1064 nm), and – with a special optical element called a frequency-doubling crystal – green (532 nm), and ultraviolet (355 nm) wavelengths.
Photodynamic Therapy
Henry W. Lim, Nicholas A. Soter in Clinical Photomedicine, 2018
The argon–pumped-dye laser is bulky, expensive, and difficult to maintain. Laser Therapeutics has developed an alternative system that appears to be more practical and user-friendly. The Laser Therapeutics system employs a solid-state, frequency-doubled Nd: YAG laser (e.g. Laserscope “KTP laser”) pumping a simplified, low-maintnenace dye laser. In addition, the next generation of photosensitizer may be at wavelengths where it is practical to use a diode laser to generate the light. Diode lasers are small and reliable, and may cost one-tenth of an argon–dye laser combination.
Transscleral cyclophotocoagulation in the treatment of glaucoma: patient selection and perspectives
Published in Expert Review of Ophthalmology, 2021
Rebecca Liebenthal, Joel S. Schuman
The method of using the diode laser is similar to that of using the Nd:YAG laser in which the laser is applied over 360° while avoiding the 3 and 9 o’clock regions. The diode laser can also be applied using a contact probe or a slit-lamp in a noncontact method. In the noncontact diode laser transscleral CPC (NCDC), the laser is set at 1200–1500 mW, with a spot size of 100–400 μM over 1 s duration. It is recommended that 30–40 spots are applied 1 mm behind the limbus. The non-contact technique is seldom used. Contact diode laser transscleral CPC (CDC) utilizes a specialized G-probe (IRIS Medical Instruments, Inc., Mountain View, CA, USA) that centers the fiber optic 1.2 mm behind the limbus. The laser is typically set to 1500–3000 mW at a 1.3–3.5 s duration; however, there is variability in the reported settings. The laser power should be increased in increments of 250 mW until am audible ‘pop’ is heard, and then reduced by 250 mW. This new power should be continued for the rest of the procedure, unless additional ‘pops’ are heard, in which case power should be reduced further. Both contact and noncontact methods have been found to be successful in treating glaucoma; however, the contact method is preferred [54,55].
The “in’s and outs” of laser hair removal: a mini review
Published in Journal of Cosmetic and Laser Therapy, 2019
Mandy M. Thomas, Nicolette N. Houreld
The Food and Drug Administration (FDA) requires that manufacturers and device users submit medical device reports (MDRs) for suspected injuries from device use or malfunction. A study conducted by Tremaine and Avram, between 1991 and December 2013 has shown diode lasers to be the second most frequently reported technology, with 252 MDRs (32). Blisters and burns were the most common adverse events. In many cases the complications were thought to occur secondary to operator error; either inadequate device maintenance or improper settings. IPL had 158 MDRs and broadband light (BBL) had 22 MDRs. The most commonly reported adverse events included burns, dyschromia and scarring. There was a total of 246 MDRs associated alexandrite (118 MDRs) and Nd:YAG (99 MDRs) lasers. The most common adverse events observed included burns, blisters and dyschromia (32).
Panretinal Photocoagulation: A Review of Complications
Published in Seminars in Ophthalmology, 2018
Shivani V. Reddy, Deeba Husain
The advent of tunable dye lasers in the mid 1970s allowed for more selective targeting of ocular tissues by using particular wavelengths, with better honing of treatment in cases of dense cataracts, vitreous hemorrhages, etc.4,5 The concurrent evolution of solid-state lasers further allowed for portability and easier laser delivery methods at the slit lamp. Diode lasers were created in the early 1990s as an alternative to gas-based lasers (argon, krypton, etc.) and liquid-based dye lasers. The first infrared diode laser (810 nm wavelength) allowed for better penetration and less scatter. Since the early 2000s, argon lasers have been largely displaced by diode, diode pumped solid state (DPSS), and optically pumped semiconductor lasers with wavelengths ranging from 532 nm to 810 nm.4,5 Conventional laser (CL) photocoagulation today is typically performed with exposure durations from 100–200 ms, spot sizes from 100–500 µm, and powers from 250–750 milliwatts (mW).
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