Lasers and Living TissuePhotobiology - Laser Light and Living Tissue
- Source: Cathy Ulrich, PT, DPT
Photobiology is the study of how light interacts with living tissue. Light from lasers has specific characteristics that light from other sources does not have.
While surgical lasers are now commonplace in the U.S. medical community, low level therapeutic lasers are a distinctly different tool. With power outputs of 500 milliWatts or less, therapeutic lasers (also called soft lasers or cold lasers) don’t burn or cut tissue; they don’t even heat tissue. They work in an entirely different way to promote tissue healing.
With more than 2500 laboratory and clinical studies performed to date, scientists are developing a picture of how low level lasers work on tissues – and often work so well. Cold lasers were used initially for skin and wound healing mainly because researchers believed that the light emitted from a laser didn’t penetrate below the layers of the skin. Later studies found that lasers actually penetrate significantly deeper than the skin – as much as 4 cm with infrared lasers.
Among the many effects that lasers produce on biological tissues, below are some of the most important for the purposes of a bodywork practice:
Increased Cellular Energy
The Liquid Crystal Matrix
- Source: Cathy Ulrich, PT, DPT
It’s been postulated that the connective tissue matrix is a living liquid crystal, a semiconductor that transmits information at times and blocks information at others depending on the circumstances. Liquid crystals are piezoelectric which means that when they’re deformed, they release electrons creating a free flow of energy throughout the matrix. They’re also thixotropic – able to change from a gel state to a solution state depending on their level of energy.
