Low Level Light Therapy – Can Laser Biostimulation Be Taken Seriously?

This article, discussing laser biostimulation in general, was also published in the September 1994 issue of Medical Laser Report.

Low Level Light Therapy – Can Laser Biostimulation Be Taken Seriously?

Irving J. Arons
Managing Director
Spectrum Consulting

The therapeutic effects of laser light on tissue -- as opposed to the surgical effects of cutting, ablating or otherwise removing tissue -- include both photodynamic therapy (light activated fluorescence for detection and diagnosis, and photoactivation or excitation of chromophores to act on the host cell) and biostimulation. In biostimulation, low powered (less than 60 mW) laser energy is absorbed by tissue or cells and is believed to cause the release of enzymes or the transformation of prostaglandins to have a therapeutic effect on the target tissue to which the laser has been applied.

For the past twenty to twenty five years, from the experimentation in 1968 by Professor Endre Mester of Hungary, the grandfather of biostimulation, low energy laser therapy, also referred to as low level laser therapy, produced by helium neon (HeNe), gallium arsenide diodes (GaAs), and yttrium aluminum garnet (YAG) lasers, have been used primarily in Europe and in Japan for the acceleration of healing of open wounds and ulcers and to alleviate the pain of swollen or arthritic joints, both in humans and in race horses and other animals.

The lasers used, defined as "soft lasers" because they produce little to no thermal effects, have been found to "heal" non-healing or slow-to-heal chronic ulcers which remained resistant to conventional therapeutic methodologies, and to stimulate nerves and the lymphatic system to speed up the healing process and reduce pain and swelling of injured tissue. These low powered lasers are believed to increase the production of collagen which provides healing for non-healing tissues, and to stimulate the production of enzymes which remove or reduce the by products of tissue inflammation and thereby reduce swelling, leading to the alleviation of pain in swollen or arthritic joints.

The various lasers, HeNe at 635 nm; diodes at between 820 to 904 nm; and the YAG at 1064 nm, are used either in CW or pulsed modes at between 15 to 60 mW levels. They are usually applied for a few minutes at each treatment, and are repeated on a daily or weekly basis until relief from the symptoms is achieved. In Asian countries, biostimulation lasers are used in place of needles to perform a form of laser acupuncture to replace the use of anaesthesia.

In a trip to the former Soviet Union with a group of medical laser specialists in the summer of 1990, we observed biostimulation lasers being used to treat angina by scanning a HeNe laser across a patient's chest, and for treating heart disease through the insertion of a HeNe laser catheter into the arteries of other patients to "cleanse their blood".

A question often asked is, why lasers rather than chromatic light? The reason is that even a milliwatt laser system can penetrate deeper into tissue that the light of a 100 W bulb. The laser's monochromatic light and coherent beam (with all of its photons being unidirectional) has a considerably higher photon density resulting in the deeper penetration and the ability to reach and act on the target tissue.

Market Potential

If the claims made about biostimulation can be shown efficacious to the satisfaction of the US FDA, we estimate that a market of between $150 to $300 million would develop within 5 years of approval, representing the sale of 60,000 to 100,000 of laser biostimulation systems at an average selling price of between $2500 to $5000. Thousands of these lasers are in use in other world areas, with annual sales of an estimated $40 million in 1994.

Over the years, a number of US companies have attempted to gain FDA marketing approval, most recently (in the late 1980s) Physio Technology (North Park, IL) and Dynatronics (Salt Lake City, UT). The latter's PMA application was rejected by the FDA in 1988 on the grounds that the clinical work submitted did not prove the effectiveness of the device in the alleviation of pain associated with rheumatoid arthritis.

The last time I looked at the companies active in biostimulation (in my medical laser report, "The Outlook for Medical Lasers: The New Technologies", published by Arthue D. Little's Decision Resources in December 1988), there were at least 6 firms operating in North America; nearly 20 in Europe; and about 6 in Japan. I am sure there are at least that many -- although probably not the same ones -- still operating around the world. The implication of an impending FDA approval should spur even greater marketing efforts and could entice additional laser companies to produce and sell systems for this lucrative market.

Now it appears that there may be hope for the approval of a "soft", biostimulation laser. Lasermedics (Stafford, TX) has conducted double-blind tests on workers afflicted with carpel tunnel syndrome at General Motors plants in Detroit, and according to the just released study data -- see the lead article on page 1 -- those people treated with the Lasermedics Microlight 830 laser showed significantly improved results compared to both those treated with a placebo and those treated by physical therapy. The company has applied for a 510 (k) exemption to market its battery-operated therapeutic laser to apply infrared light to alleviate pain in soft tissue, and is supposedly in line for FDA review of its application. With the results of the GM study, and the added work on the effects of 830 nm laser light on median nerve function done at the Mayo Clinic (Rochester, MN), the company may be poised for a breakthrough in the use of biostimulation lasers in the US.