Laser/Light Therapy

Laser/Light Therapy

1. Light amplification by the stimulated emission of radiation (LASER)

   • device that concentrates high energies into narrow beam of light
     • homogenous beam of light
     • amount of energy in a photon is a function of wavelength and frequency

2. Albert Einstein - first described theory that was transformed into laser therapy

3. Classified by FDA on class levels 1-4

   • class 1 = minimum; 4 - maximum
   • most therapeutic lasers are class 3B and 4

4. compressed light of a wavelength from the cold, red part of the spectrum of electromagnetic radiation (1 precise color)

   • monochromatic - single wavelength; single color
   • coherent - travels in straight line; in phase
   • polarized or collimated - concentrates bean in a defined location/spot

5. types

   • helium neon lasers
     • uses a gas mixture in a pressurized tube
     • creates a laser in the red portion of electromagnetic spectrum
     • about 632.8 nanometers wavelength
     • energy depth - 0.8-15 mm deep
   • Gallium Arsenide lasers
     • utilize a diode to produce an infrared (invisible) laser
       • diode laser composed of semiconductor silicone materials precisely cut and layered
     • about 780-904 nanometer wavelength
     • energy depth up to 2 cm

6. What is light therapy

   • polarized polychromic light with different wavelengths
     • semiconductor - insulators into electrical conductors
   • LEDs - light emitting diodes
   • SLDs - super bright LEDs or superluminous diodes
   • monochromatic but not coherent and not collimated
     • more scattered = less energy
   • wavelength
     • 600-900 nm
     • determined by semiconductor material
     • claims up to 5 cm deep

7. Two types/classes used in physical rehab

   • class 3 - clinics have class 3B
     • are less than 500 mw in power - referred to as cold lasers or low-level laser therapy (LLLT)
   • class 4
     • greater than 500 mw in power - referred to as high-power laser therapy (HPLT)
   • 2 types of light therapy
     • LEDs
     • SLFs

8. why laser or light therapy?

   • biostimulative light energy to body's cells is converted into chemical energy to promote natural healing and pain relief
     • class III: penetrates skin with no appreciable heating effects
     • class IV: heats tissue due to power output
   • red light and near infrared light
     • absorbed by the mitochondrial and cytochromes present in all cells
     • respiratory chain enzymes (cytochromes) are the primary light-absorbing molecules
   • Optimizes the immune response of blood, has anti-inflammatory, and immunosuppressive effects