Doc. MUDr. Leoš Středa, Ph.D. .
APPLIANCES FOR REGENERATION AND AESTHETIC MEDICINE 4
B82172 Course in English 1st Faculty of Medicine Charles University
4. SOFT-LASERS (BIOSTIMULATION LASERS)
Biostimulation lasers LASER acronym for Light Amplification by Stimulated Emission of Radiation device that emits light through a process of optical amplification based on the stimulated emission of photons This principle of the laser, Albert Einstein in 1917 explained physically, but the first laser was developed in 1960.
Laser beam is 1. monochromatic (i.e. single wavelenght) 2. directional 3. coherent (beam energy is concentrated to
one single spot and laser beam oscillates in phase)
Categories of lasers According to power output: Low power (noninvasive) biostimulation soft-lasers with power in milliwatts Power lasers (hard-lasers) with output power in watts According to environment which arises the beam: Semiconductor lasers (polovodičové - most widespread) Gas lasers (He-Ne) Chemical, dye, solid state (ruby) lasers
Soft-lasers The development was slower than development
of power lasers used in surgery The first were He-Ne lasers operating in continuous mode only Semiconductor lasers using laser diodes as a source of laser radiation
Soft-laser effects Biostimulation (collagen synthesis, blood vessels formation, epithelization promoting) synthesis, formation of blood vessels, promotingepithelization). Cell response to stimulation disappears with higher power of
laser radiation. Anti-inflammatory (increased phagocytic activity of leukocytes) Analgesic (it can evoke desensitation of senzory membrane - pozitivní desenzibilizace senzorické membrány)
Mechanism of Effects The effects of soft laser is relatively independent on the wavelength (in contrast to power-lasers). Only the penetration depth is dependant from wavelenght. It works at the molecular level: affects the respiratory chain enzymes, increases mitochondrial DNA replication, increases enzyme activity. Laser beam affects membrane potential, probably through changes in membrane permeability to ions Na+, K+ a Ca++.
Soft-laser wavelength A shorter wavelength means less depth of penetration into tissues…but…at the same time it means a greater concentration of energy to treatment location.
Soft-laser wavelength(2) The wavelength determines the absorption rate significantly. It also determines an iteraction with tissue lawyers, where the beam passes. Different absorption of laser beam in tissue affect mostly three components:
water hemoglobin melanin
Soft-laser wavelength (3) If we need to absorbe laser energy in the surface layers of the skin or mucous membrane, it is better to use lasers with wavelengths of 630-750 nm If we need to irradiate deeper layers (e.g because of musculoskeletal disability), it is better to use laser with wavelengths of 830904 nm. Interesting fact: diode light has deeper penetration than laser beam.
Lasers wavelenght vs. diodes Higher LED light penetrating power over lasers was discovered last year by Prof. Arisawa, Nicolau and Esper from Center for Laser Therapy and Photobiology, Brasilia.
Lasers in Medical Science May 2011 Springer-Verlag, Londýn
Soft-lasers Indications Dermatology - unhealed wounds, leg ulcers, herpes Cosmetics - fresh scars, acne, bruises
(modřiny) Medicine of pain - e.g. analgesic effect
of post herpetic pain
Safety requirements for laser manipulations Sufficient eye protection of medical
staff and patient treated Not aim the laser probe into the eye or its close vicinity. The laser beam is collimated (rovnoběžný) radiation and if passes through the eye lens it could be concentrated to one point of the retina.
Protective glasses Protective eyewear for patients and medical staff. Essential for some laser classes. Risk of permanent damage in seconds or even less time. Glasses absorb wavelengths that the laser emits.
Laser Classes: Lasers are usually labeled with a safety class number: Class I - power output in microWatts (e.g. CD players), inherently safe. Class II – power output max. 1mW (laser pointers), safe during normal use; eye blink reflex will prevent damage. Class IIIa – power output usually up to 5 mW, small risk of eye damage within the time of the blink reflex. Class IIIb – power output up to 500 mW, can cause immediate eye damage upon exposure. Protecting glasses, key locked, acustic signal necessary, warning board in the workplace. Class IV – lasers can burn skin, track of radiation must be covered (zakrytá dráha záření).
Types of lasers  Small (pocket) lasers with interchangeable heads, can work with different frequency pulses.
Desktop lasers user´s comfort, numerous features and applications
Cosmetic indications Environmentally damaged hair. Circular motion, applications in spirals, the laser probe directed perpendicular (kolmo) to the head. For effective application, direct contact with the skin is necessary. Laser beams may affect directly the hair follicle area, from which hair grows. The usual cure 10 to 18 applications for 15 to 20 minutes. A complete cycle consists of 10 to 18 applications. Repetition available at interval from 20 to 60 days.
Cosmetic indications (2) Scars. Fresher scars respond better. Scars should not be more than 6 months. Irradiate from 10 to 15minutes scar edges with small meandering or spiral motions. Application 1-2times a week, the whole treatment consists of 8 to 12 aplications. After the 1 month break the cycle can continue. No effect in scars more than 1 year.
Cosmetic indications (3) Acne. Application lasts for a 5-10 minutes daily. Planar (ploĹĄnĂŠ) treatment of the affected area. Combine with targeted application on infected spots for 20 seconds. Total number of applications in the course of treatment involves 10 to 15 applications. After a 20 to 60 days can continue further cycle.
Cosmetic indications (4) Stretch marks (striae) are treated kinetically. Treatment with small spirals, laser probe moves from one edge to the other. For applications are the same restrictions as for the scars. The effect is stretch mark fade out (vyblednutĂ), not total elimination. The fresher they are, the more pronounced effect of the laser is visible.
Cosmetic indications (5)
Nail bed treatment is used in damaged nails. Weekly applications , the total cycle includes 10-15 applications. A single application usually takes 1-2 minutes on each nail bed, both hands together then 1020 minutes. We operate kinetically on each bed. If necessary, the full course can be repeated after one month break.
Cosmetic indications (6) Herpes simplex. Daily treatment for 3-5 days, each application takes usually 1-2 minutes. Treat the herpes edge by spiral movements. Let the laser beam treat every spot for about 10 seconds
Cosmetic indications (7) Bruising (modřina, hematoma) is faster absorbed after laser applications. Fading apparent during hematoma is already apparent during first applications. Daily treatment, a total of 10 applications, each for 5-10 minutes. We operate kinetically across whole area. Application is not suitable in the case of the black eye, because too close to the eye (risk to affect eye).
Cosmetic indications (8) Allergic skin rashes (e.g. hypersensitivity to cosmetics). Every day treatment, approximately 1 minute/1 cm2. The treatment is performed kinetically locally. The full application course usually performed until exanthema disappearance.
Cosmetic indications (9) Skin changes persisting after the treatment of eczema or psoriasis or similar skin disease. It is treated kinetically whole area 1-2times a week, each application takes 10-15 minutes. Total number of applications, 1015, repeated treatment possible with a monthly interval.
Cosmetic indications (10) Anti aging. Laser beam improves blood circulation and nourishment of treated tissues. It leads to fresh and youthful appearance. Series of 10 to 18 applications 1x per week, each application takes 5-10 minutes. The laser probe operates over the whole area.