Low level light therapy (L3T), or cold laser therapy, is becoming an important component of many integrative veterinary practices, and is most often used for pain control and tissue healing. A laser produces electromagnetic radiation in the visible and near infrared light band (400 to 10,000 nanometers). Cutting lasers are usually over 1,500 nm, while therapeutic lasers will be under 1,500 nm.
All living cells emit units of light (biophoton emission) at the point of excitement (when the mitotic split occurs). Biophoton emission can be an important source of information about an organism’s status. When muscles or nerves are activated, the intensity of biophoton emission increases. Characteristics of biophoton emission indicate the health of the cells and whether they are multiplying or dying.1 It is possible to discriminate between cancer cells and normal cells by measuring the spontaneous low level luminescence.
Electromagnetic radiation reacts two ways; partially as a wave movement with all the typical properties of waves (wavelength, etc.) and partially as a flow formed of particles with their properties of mass, quantified energy, etc.2 Ancient Qigong texts speak of absorbing light energy from the sun, moon and stars and of the body radiating varying degrees and qualities of light depending on the individual’s state of health and consciousness.1
L3T is based on the quantum physics premise that each living cell or matrix has an inherent vibration, or coherent radiation. “Treatment with laser therapy is not based on heat development but on photochemical and photobiological effects in cells and tissues,” say Tuner and Hode. 3 “Therapeutic lasers cannot penetrate the tissue more than a fraction of a millimeter, so there is no other primary responding tissue other than the outer part of the dermis.”
Still, such irradiation has “secondary systemic effects.” Therefore, the light “leads in turn to a number of secondary effects (secondary responses), which have been studied and measured in various contexts: increased cell metabolism and collagen synthesis in fibroblasts, increased action potential of nerve cells, stimulation of the formation of DNA and RNA in the cell nucleus, local effects on the immune system, increased formation of capillaries by the release of growth factors, increased activity of leukocytes, transformation of fibroblasts to myofibroblasts, and a great number of other measured effects.”
Three parameters of laser therapy
1. Power is probably the most talked about parameter in lasers. Its impact determines the treatment time needed to deliver an adequate dosage to the target. Lasers, like ultrasound, stimulate at lower levels. At higher levels, they become destructive.4 Most cutting lasers are over 100 W and only penetrate 1 cm at a time. Robert Becker, MD, noted in his 1985 book, The Body Electric, Electromagnetism and the Foundation of Life,5 that plants could regenerate severed branches at three times the normal rate by applying two to three microamperes for five days. A microampere is one-millionth of an ampere. “Larger amounts of electricity killed the cells and had no growth-enhancing effect,” says Dr. Becker. In his experiments with cellular regeneration, he noted: “The best window [of current] was somewhere between 200 and 700 picoamps. This was an infinitesimal tickle of electricity, far less than anything a human could feel even on the most sensitive tissue, such as the tongue, but it was enough to goose the cell into unlocking all its genes for potential use.” Possibly the most important article to be aware of regarding the effects of the energy output of lasers was published in the January 2006 issue of the authoritative journal Lasers in Surgery and Medicine.6 This article noted that a lower dose of laser irradiation “has a stimulatory influence on wounded fibroblasts with an increase in cell proliferation and cell viability without adversely increasing the amount of cellular and molecular damage. Higher doses were characterized by a decrease in cell viability and cell proliferation with a significant amount of damage to the cell membrane and DNA.” These authors further noted that by spreading the light out over 3.3 cm, “the light is divergent and is not as harmful as a narrow parallel beam that allows the entire volume of intense laser light to be focused or concentrated on one small area.” The laser discussed in this study used only 3 MW of power. The FDA approves class 3a, 3b and 4 lasers based on the amount of radiation exposure. Class 4 lasers usually create heat.
2. Dosage measures the total amount of energy delivered per unit of area and is expressed in J/cm2. Tuner and Hode recommend 1 to 10 J/cm2 for the treatment of superficial or deep pain conditions; 16 J/cm2 has been reported to cause irreversible cellular and genetic damage.6 The energy delivered equals the power of the machine multiplied by the length of treatment. Take the energy delivered and divide it into the area being treated to arrive at the energy density.7 1 W delivers 1 joule in 1 second 1 MW delivers 1 joule in 1,000 seconds (16 minutes) 100 MW delivers 1 joule in 10 seconds
In a study at the Biological and Medical Research Department in Riyadh, Saudi Arabia, Farouk Al-Watban utilized surgically induced wounds in rats to conclude that 10 J/cm2 achieves the highest stimulated rate of healing, and that increasing the dose will result in an inhibited healing rate.8 There seems to be significant evidence to show that biostimulation effects are governed by the Arndt Shultz law of biology. Weak stimuli excite physiological activity while strong stimuli retard it.
3. Wavelength is another key parameter. Laser is pure light and has only one wavelength.9 Other light is very disorganized. Just as pure sound can cause glass to self-oscillate and break, pure light can enable cells to self-resonate.
Wavelength determines how deep laser energy penetrates into tissue.6 The energy of photons is inversely related to wavelength. Physics formulas can be used to show how particles react, and demonstrate that the bigger the wavelength of a photon, the smaller its energy.10 “Any wavelength will have a biological effect,” notes Turner. Karu adds: “The 632.8 nm and the 820 nm are the most common wavelengths used in therapeutic light sources.” Turner and Baxter both note: “Shorter wavelengths have higher energy.”
L3T has no recorded side effects in over 1,700 publications. Its application to tissue is totally safe, non-invasive and non-toxic, and should (could) replace medication, most physiotherapeutic modalities, and in many situations, surgical approaches.11
¹ Cohen, Kenneth S. The Way of Qigong — The Art and Science of Chinese Energy Healing, Ballantine Books, New York,1997. ² Pekka, L, The Physics of Laser — Low Level Laser Therapy as a Medical Treatment Modality. ³Tuner, Jan and Hode, Lars. Laser Therapy Clinical Practice and Scientific Background, Prima Books, 2002. 4 “Understand the Tech Before Buying a Laser”, DCPI Staff, Dynamic Chiropractic. 5 Karu, Tina. “Low-Power Laser Therapy”, Chapter 48 in Biomedical Photonics Handbook, Tuan Vo-Dinh, CRS Press, 2003. 6 Harrington, Phil, DC. “Physics for Chiropractors, Part 3. Can Laser Therapy Damage Tissue?” Dynamic Chiropractic, January 1, 2010, Vol. 28 Issue 01. 7 Harrington, Phil, DC, “Physics for Chiropractors. Calculating the Energy Density of a Therapy Laser,” Dynamic Chiropractic, January 1, 2009, Vol. 27, Issue 01. 8 Al-Watban, MSc, PhD, FASLMS and Delgado, Glenda D. “Erchonia Laser on Healing Scapel Wound on Rats”, Laser Medical Section, Biological and Medical Research Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. 9 Kauffman, Rick, DC, CCEP, CAC.“Veterinary Cold Laser Therapy. The animal’s path to wellness and anti-aging”, Cold Laser Seminar, Denver, CO, August, 2009. 12 Bryant, Rebecca. “Low-level laser outshines other modalities”, Cosmetic Surgery Times Special Report, July1, 2004. 10 Pointinen, Pekka J., MD,PhD. Low Level Laser Therapy as a Medical Treatment Modality, Art Urpo Ltd, Tampere, 1992, page 17. 11 Kahn, Fred MD, FRCS(c) and Fitz-Ritson, Don. “Lasers Heal. Chiropractors Could Benefit from this Technology”, Dynamic Chiropractic, November 18, 1996, Vol. 14, Issue 24. Dr. Bill Ormston graduated from Iowa State University College of Veterinary Medicine in 1988. After attending Options For Animals in 1998 he received certification from the AVCA and began using chiropractic to treat his animal patients. Jubilee Animal Health is a mobile mixed animal practice in the Dallas Metroplex area where he cares for pets and horses using mostly alternative methods. He is one of the founding instructors of the post graduate course in Animal Chiropractic at Parker Chiropractic College in Dallas. Dr.O has lectured both nationally and internationally on Animal Chiropractic and biomechanics and gait analysis in the quadruped. He has written booklets on chiropractic care in the dog and horse and a book about blending traditional and alternative care in pets.