Lasers in Medicine: Healing with Light
Suzanne Amador Kane, Boris A. Gelman in Introduction to Physics in Modern Medicine, 2020
Infrared lasers such as the Nd:YAG and carbon dioxide lasers offer high powers and are popular choices for general purpose photovaporization. The Nd:YAG operating in the infrared at 1064 nm is not absorbed strongly by blood, water, or tissue (Figure 3.26). However, it still transfers energy effectively to most tissues through strong scattering, a process that is not as specifically dependent on wavelength. The carbon dioxide laser also operates in the infrared at a wavelength of 10,600 nm. Unlike visible light, this wavelength is strongly absorbed by water. In fact, over 99% of the beam is absorbed within 50 microns of water. This makes the carbon dioxide laser a general purpose laser for many procedures where no pigment is available to selectively absorb the laser light. The infrared light of the erbium:YAG is both powerful and strongly absorbed. Because its wavelength is shorter than the carbon dioxide laser, it can be focused down to smaller spot sizes, allowing it to drill bone and dental enamel.
Tumours of the Larynx
John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford in Head & Neck Surgery Plastic Surgery, 2018
Excision technique There is no gold standard in the tool used to resect the LD lesion. However, cold steel or laser resection is recommended over monopolar cautery If laser excision is contemplated, carbon dioxide laser is recommended owing to the laser properties enabling minimal penetration, thus reducing collateral damage.Laser ablation (i.e. laser used on the surface of the lesion to destroy the epithelium rather than excising it) is discouraged as no specimen will be available for diagnosis and there is a higher risk of damage to the voice.Vocal cord stripping is not recommended at all owing to the high risk of damage to the vocal cord.Radiotherapy should be offered only in rare circumstances for patients where there is very high risk/suspicion of conversion to malignancy and surgical resection is not possible owing to patient or tumour factors.
Laser Photocoagulation Principles
John P. Papp in Endoscopie Control of Gastrointestinal Hemorrhage, 2019
Figure 3 illustrates the impact of the three most important surgical laser beams upon a specimen of tissue. The carbon dioxide laser operates at 10.6 μm wavelength in the middle infrared region of the electromagnetic spectrum. This wavelength is such that the water molecule strikes up a sympathetic vibration. When this happens, energy is extracted from a laser beam and converted to heat. Since tissue contains water, the CO2 laser beam is rapidly absorbed by tissue. Thus, as shown in Figure 3, its penetration is shallow. When the radiation from a CO2 laser is focused on tissue at high-power levels, it causes rapid evaporation of cell water, which in turn forms a crater. A series of side-by-side craters forms an incision. The CO2 laser is a popular laser scalpel.
Topical anesthetics for pediatric laser treatment
Published in Journal of Cosmetic and Laser Therapy, 2019
Marija Stevic, Ana Vlajkovic, Branislav Trifunovic, Ivan Rakic, Nina Ristic, Ivana Budic, Vesna Marjanovic, Marija Jovanovski-Srceva, Dusica Simic
The carbon-dioxide laser emits light at wavelength of 10,600 nm in the far-infrared spectrum (23). The active laser medium is a mixture of three different gases consisting of 10% carbon dioxide, 10–20% nitrogen, and the remainder is helium. The working principle is based on making microscopic areas of thermal damage that stimulate collagen production and replace damaged skin surface by new epidermal cells. Carbon-dioxide has proved moderately useful in the treatment of keloids, moles, acne scarring, viral warts, rhinophyma, actinic keratosis, stretch marks, and pearly penile papules. Adverse effects and complications associated with CO2 laser resurfacing include prolonged erythema, acne or milia formation, wound infections, post-inflammatory hyperpigmentation, delayed hypopigmentation, herpes simplex virus reactivation, hypertrophic scarring, and ectropion formation (2).
Severe laryngeal sarcoidosis in a child managed by intralesional steroid, debulking, and methotrexate
Published in Acta Oto-Laryngologica Case Reports, 2022
Jesper Stensig Aa, Peter Toftedal, Joyce Dominique Horsmans Schultz, Søren Fast
The therapeutic strategy in a child with laryngeal sarcoidosis depends on the severity of the disease. In asymptomatic patients, therapy may not be needed since spontaneous resolution occurs in most cases within 12-36 months [5]. On the other hand, if airway patency is threatened, surgical treatment and even tracheotomy may be necessary [6]. In the case presented here, the patient had trouble breathing, and we decided to administer intralesional corticosteroid injections which had previously been used successfully [7]. In addition, due to a very swollen and retro-flexed epiglottis, we decided to perform cold steel debulking and sample tissue from the lingual side of the epiglottis to create more space in the laryngeal introitus. Although the patient reported immediate improvement of dyspnea, we can only speculate whether this resulted from debulking or an early corticosteroid effect. In adults, Krespi et al. obtained good results with intralesional corticosteroid alone [7]. If airway obstruction is evident and extensive tissue reduction is required, a carbon dioxide laser is reported to be a safe and effective option. In adults, Colin R. Butler et al. described 10 patients treated with minimally invasive endoscopic laser surgery and intralesional corticosteroid injection [8]. Symptoms improved with minimal morbidity, and a reduced need for systemic corticosteroids was reported.
Patient reported vaginal laxity, sexual function and stress incontinence improvement following vaginal rejuvenation with fractional carbon dioxide laser
Published in Journal of Plastic Surgery and Hand Surgery, 2021
Gaye Toplu, Merdan Serin, Toygar Unveren, Dincer Altinel
Various surgical procedures have been reported as successful in improving the sexual dysfunction and vaginal laxity [10]. But, despite their success, these procedures are associated with rare but serious complications such as infection and bleeding [11]. In addition, recovery period following these surgical procedures can be as long as 6–8 weeks which means retraining from sexual activity in this period. In contrast, fast recovery is possible following the procedure with carbon dioxide laser treatment. In this study the survey regarding the level of discomfort during and after the procedure was reported as none or low in 74% and 82% of the patients, respectively. This is a definite advantage of non-invasive methods such as the laser and radiofrequency over surgical procedures [12,13–16].
Related Knowledge Centers
- Carbon Dioxide
- Germanium
- Helium
- Nitrogen
- Laser
- Hydrogen
- Xenon
- Silvering
- Zinc Selenide
- Reflection