Laser & Light Therapy

1. Laser & Light Therapy

2. What is Laser Therapy? • Light Amplification by the Stimulated Emission of Radiation • Compressed light of a wavelength from the cold, red part of the spectrum of electromagnetic radiation • Monochromatic - single wavelength, single color • Coherent - travels in straight line • Polarized - concentrates its beam in a defined location/spot

4. History • Albert Einstein – 1st described this theory that was transformed in to laser therapy • By the end of the 60’s, Endre Mester (Hungary) - • was reporting on wound healing through laser therapy • In early 1960’s, the 1st low level laser was developed. • In Feb. 2002, the MicroLight 830 (ML830) received FDA approval for Carpal Tunnel Syndrome Treatment (research treatment) • Laser therapy – has been studied in Europe for past 25-30 years; US 15-20 years

5. Therapeutic Laser Low Level Laser Therapy Low Power Laser Therapy Low Level Laser Low Power Laser Low-energy Laser Soft Laser Low-reactive-level Laser Low-intensity-level Laser Photobiostimulation Laser Photobiomodulation Laser Mid-Laser Medical Laser Biostimulating Laser Bioregulating Laser What’s in a Name?

6. What Does It Do? • Laser light waves penetrate the skin with no heating effect, no damage to skin & no side effects. • **Laser light directs biostimulative light energy to the body’s cells which convert into chemical energy to promote natural healing & pain relief. • Optimizes the immune responses of blood & has anti-inflammatory & immunosuppressive effects.

7. Physiological Effects • Biostimulation – improved metabolism, increase of cell metabolism • Increases speed, quality & tensile strength of tissue repair • Improved blood circulation & vasodilation • Increases blood supply • Increases ATP production • Analgesic effect • Relieves acute/chronic pain • Anti-inflammatory & anti-edematous effects • Reduces inflammation

8. Physiological Effects • Stimulation of wound healing • Promotes faster wound healing/clot formation • Helps generate new & healthy cells & tissue • Increase collagen production • Develops collagen & muscle tissue • Increase macrophage activity • Stimulates immune system • Alter nerve conduction velocity • Stimulates nerve function

9. Tissue & Cellular Response • Red light affects all cell types • Absorbed by the mitochondrial present in all cells • Cytochromes (respiratory chain enzymes) within the mitochondria have been identified as the primary biostimulation chromophores (primary light-absorbing molecules). • Since enzymes are catalysts with the capability of processing thousands of substrate molecules, they provide amplification of initiation of a biological response with light. • Infrared light is more selective absorbed by specific proteins in the cell membrane & affects permeability directly

11. Tissue & Cellular Response • Cytochromes function to couple the release of energy from cellular metabolites to the formation of high energy phosphate bonds in adenosine triphosphate (ATP) • ATP is used to drive cell metabolism (maintain membrane potentials, synthesize proteins & power cell motility & replication). • Assuming cytochromes also can absorb energy directly from illumination, it is possible that during LLLT light energy can be transferred to cell metabolism via the synthesis of ATP.

12. Mitochondria

14. Tissue & Cellular Response • Magnitude of tissue’s reaction are based on physical characteristics of: • Output wavelength/frequency • Density of power • Duration of treatment • Vascularity of target tissues • Direct effect - occurs from absorption of photons • Indirect effect – produced by chemical events caused by interaction of photons emitted from laser & the tissues

15. LASER Regulation • LASERs - classified by the FDA’s Center for Devices & Radiological Health based on the Accessible Emission Limit (AEL). • Class Levels 1-4 • 1 = incapable of producing damaging radiation levels (laser printers & CD players) • 2 = low-power visible lasers (400-700 nm wavelength, 1 mW) • 3 = medium-power lasers - needs eye protection • 3a – up to 5 mW • 3b** – 5 mw-500 mW • 4 = high-power lasers– presents fire hazard (exceeds 500 mW)

16. Laser Generators • Components of a generator: • Power supply – electrical power supply that can deliver up to 10,000 volts & 100’s amps • Lasing medium – gas, solid, liquid • Pumping device – • high voltage, photoflash lamps, radio-frequency oscillators or other lasers (pumping is used to describe the process of elevating an orbiting electron to a higher, excited energy level) • Optical resonant cavity – contains lasing medium

17. Types of Lasers • 4 categories of lasers • Crystal & Glass (solid - rod) • Synthetic ruby & others (synthetic ensures purity) • Gas (chamber) – 1961 • HeNe, argon, CO2, & others (HeNe under investigation) • Semiconductor (diode - channel)- 1962 • Gallium Arsenide (GaAs under investigation) • Liquid (Dye) - Organic dyes as lasing medium • Chemical – extremely high powered, frequently used for military purposes

18. High Surgical Lasers Hard Lasers Thermal Energy – 3000-10000 mW Low Medical Lasers Soft Lasers Subthermal Energy – 1-500 mW Therapeutic (Cold) lasers produce maximum output of 90 mW or less 600-1000 nm light High vs. Low Level Lasers

19. Infrared Light Therapy • SLD – Super Luminous Diode • Brighter • LED – Light Emitting Diode

20. Laser Light Properties • Monochromaticity • 1 color – 1 wavelength • <400 nm • Ultraviolet spectrum • Coherence • Waves same length & traveling in same phase relationship • 400-700 nm • Visible • Collimation • Degree to which beam remains parallel with distance • 700-10,000 nm • Infrared

21. Patient Need medical history & proper diagnosis Diabetes – may alter clinical efficacy Medications Photosensitivity (antibiotics) Pigmentation Dark skin absorbs light energy better Laser Wavelength Output power Average power Intensity Dosage Parameters

22. Parameters - Wavelength • Nanometers (nm) • Longer wavelength (lower frequency) = greater penetration • Not fully determined • Wavelength is affected by power

23. Output Power Watts or milliwatts (W or mW) Important in categorizing laser for safety Not adjustable Power Density (intensity) W or mW/cm2 Takes into consideration – actual beam diameter If light spread over lager area – lower power density Beam diameter determines power density Average Power Continuous or pulse-train (burst) frequency mode Knowing average power is important in determining dosage with pulsed laser If laser is continuous – avg. power = peak output power If laser is pulsed (burst) then avg. power is = to peak output power X duty cycle Parameters – Power

24. Dosage (D) Amount of energy applied per unit area Measured in Joules/square cm (J/cm2) Joule – unit of energy 1 Joule = 1 W/sec Dosage is dependent on: Output of laser in mW Time of exposure in seconds Beam surface area of laser in cm2 Various dosage ranges per site (1-9 J/cm2) Parameters – Energy Density

25. Parameters – Energy Density • Recommended Dosage Range • Therapeutic response = 0.001-10 J/cm2 • Minimal window threshold to elicit response • Too much – suppressive effect • Open wounds – 0.5-1.0 J/cm2 • Intact skin – 2.0-4.0 J/cm2 • Average treatment – 6 /cm2

26. Helium Neon Lasers • Uses a gas mixture in a pressurized tube • Now available in semiconductor laser • Emits red light • Wavelength: 632.8 nm • Power output: 1.0-25.0 mW • Energy depth: 6-10 mm • The higher the output lasers (even though they are still low power) allow reduced delivery time

27. Indium-Gallium-Aluminum-Phosphide • InGaAip • Replacing HeNe lasers • Semiconductor • Wavelength: 630-700 nm • Power output: same as HeNe • Energy depth: superficial wound care

28. Gallium Arsenide • Semiconductor - produces an infrared (invisible) laser • Wavelength: 904–910 nm • Power output: may produce up to 100 mW • Energy depth: 30-50 mm • Short pulse-train (burst) duration (100-200 ns)

29. Gallium Aluminum Arsenide • GaAIAs • Semiconductor • Wavelength: 780-890 nm • Power Output: 30-100 mW (up to 1000 mW) • Energy Depth:

30. What Does it Look Like? • http://www.laserhealthsystems.com/omegaofferings.htm • http://www.thorlaser.com/products/

31. Indications Soft tissue injuries Fractures Osteoarthritis, Rheumatoid Arthritis Pain Wounds & Ulcers Acupuncture Indications

32. Contraindications • Contraindications • Application over eyes • Possibly can damage cellular structure or DNA • Cancerous growths • Pregnancy – over & around uterus • Over cardiac region & Vagus nerve • Growth plates in children • Over & around thyroid gland & endocrine glands • Patients who have been pre-treated with one or more photosensitizers

33. Treatment Precautions • Better to underexpose than to overexpose • Avoid direct exposure into eyes (If lasing for extended periods of time, safety glasses are recommended) • May experience a syncope episode during treatment during chronic pain, but very rare • If icing – use BEFORE phototherapy • Enhances light penetration • If using heat therapy – use AFTER phototherapy • Decreases light penetration

34. Treatment Techniques • Gridding Technique • Divide treatment areas into grids of square centimeters • Scanning Technique • No contact between laser tip in skin; tip is held 5-10 mm from wound • Wanding Technique • A grid area is bathed with the laser in an oscillating fashion; distance should be no farther than 1 cm from skin • Point Application (Acupuncture point)

35. Simple For general application, only treatment time & pulse rate vary Dosage Most important variable in laser therapy & may be difficult to determine because of the above conditions Handheld applicator Tip should be in light contact with skin while laser is engaged for calculated time Maintain laser perpendicular to treatment surface Firm contact unless open wound Clean area prior to treatment Begin with minimal treatment and gradually increase Check for pre/post-treatment changes Ask the patient how they are doing prior to next treatment May have to adjust dosage Treatment Techniques

36. Dynatron’s Solaris D880 Infrared Therapy • 880 nm wavelength – SLD (32 ) (deep) • 660 nm – LED (4) (superficial) • 10 minute max. treatment or 60 Joules • Place probe on treatment area. Maintain constant contact with the skin. • Do not bathe the area with the probe. • FDA cleared to “provide topical heating for temporary increase in blood circulation, temporary relief of minor muscle & joint aches, pain & stiffness & relaxation of muscles; for muscle spasms & minor pain & stiffness associated with arthritis.” • Dynatron Solaris 709

37. MedX Laser & Light Therapy • Laser probe • SLD (2)

38. Miscellaneous • www.geocities.com/altmedd/laser.htm • http://laserhealing.net/lowlevel.html • Journal of Laser Therapy • www.walt.nu/journal.htm