There were 5 groups of rats in the study. Groups 2 through 5 were injured in a controlled operation. Groups 3 through 5 were given different dosage of laser therapy.
Group 1: No damage
Group 2: Damaged and then area treated with placebo
Group 3: Damaged and given non-optimal therapy
Group 4: Damaged and optimal dosage
Group 5: Damaged and non-optimal therapy
Any laser therapy showed a significant improvement over no laser and the optimal laser (Group 4 with a total dosage of 4 j/cm^2) showed no difference from the uninjured tissue. The image below show the group 2 and group 4 tissue under a polarization microscope.
In conclusion, the results of this study indicate that LLLT can be used to reduce inflammatory musculoskeletal pain, using an Irradia AB laser, at a dosage of 1.8 J on each of three 0.5 cm2 points along the Achilles tendon (for a total of 5.4 J for the session), with the laser emitting a 904 nm wavelength. a power density of 20 mW/cm2, at a frequency of 5,000 Hz, with an average power of 10 mW for each of the three diodes, peak power of 10W for each diode, treating for only one session.
Low Level Laser Therapy still has many critics and is not readily accepted as a natural treatment modality in all countries. One main point emphasized by the critics is the lack of scientific documentation. While this was a valid point in the 80s and partly in the beginning of the 90s, is it still a solid argument? There are more than 2000 published studies and the vast majority of these report positive biological effects from Low Level Laser Therapy (LLLT).
The heart of a scientific documentation is the double blind clinical studies. There are some 140 such studies in the field of LLLT and it may come as a suprise to many critics that more than 100 of these are positive. In fact, even most advocaters of LLLT are unaware of this fact. The aim of this Editorial is to disseminate this information to the LLLT community.
Some of the negative double blind studies are well designed and should be taken seriously. Certainly all indications and all parameters cannot work. However, a number of the often quoted negative double blind studies suffer from flaws of several kinds. Some of this is outlined on http://www.laser.nu/lllt/LLLT_critic_on_critics.htm which is a chapter from our recent book "Low Level Laser Therapy - clinical practice and scientific background"
A closer analysis of 100 positive double blind studies will be presented at Laser Florence '99 (October 28-31) and will also appear in the EMLA Millennium laser book.
A weakness in the list is that many double blind studies have only been identified in the abstract form. They may have been published in full at a later stage, but not found by us. 14 studies have only been found as references in reference lists and these have not been found in spite of intensive efforts. For a complete analysis of the 100 positive double blind studies we need the assistance of the visitors of LaserWorld. In the following list abstracts are marked in red and studies not found marked in green. If you have any information about the green studies please contact us. And if you know that an abstract has been published in a journal, please do likewise. The more complete the list is, the better for the LLLT community.
The studies published in journals are listed in full in the book mentioned above.
Atsumi K et al. Biostimulation effect of low-power energy diode laser for pain relief. Lasers Surg Med. 1987; 7: 77.
Barabas K et al. Controlled clinical and experimental examinations on rheumatoid arthritis patients and synovial membranes performed with neodym phosphate glas laser irradiation. Proc. 7th Congr Internat Soc for Laser Surg and Med, Munich June 1987. Abstract no 216a.
Boerner E et al. Double-blind study on the efficacy of the lasertherapy. SPIE Proc. 1996. Vol. 2929: 75-79.
Cheng R. Combined treatments of electrotherapy plus soft laser therapy has synergistic effect in pain relief and disease healing. Surgical and Medical Lasers. 1990; 3 (3): 135
Cieslar G et al. Effect of low-power laser radiation in the treatment of the motional system overloading syndromes. SPIE Proc. Vol 3198. 1997, pp. 76-82.
Emmanoulidis O et al. CW IR low-power laser application significantly accelerates chronic pain relief rehabilitation of professional athletes. A double blind study. Lasers Surg Med. 1986; 6: 173.
Haruki E, Yamaguchi S. Double blind evaluation of low energy laser treatment for painful disease. J Phys Med. 1995; 6: 60-67. (In Japanese with English abstract)
Hopkins G O et al. Double blind cross over study of laser versus placebo in the treatment of tennis elbow. Proc Internat Congr on Lasers, "Laser Bologna". 1985: 210. Monduzzi Editore S.p.A., Bologna. Hoshino H et al. The effect of low reactive level laser therapy in the field of orthopedic surgery. Chronic Pain. 1994; 13: 101-109. (In Japanese with English abstract)
Hoteya K et al. Effects of a 1 W GaAlAs diode laser in the field of orthopedics. In: Meeting Report: The first Congress of the International Association for Laser and Sports Medicine. Tokyo, 1997. Laser Therapy 1997; 9 (4): 185.
Kamikawa K et al. Double blind experiences with mid-Lasers in Japan. 1985. Proc Int Congr on Lasers, "Laser Bologna". 1985: 165-169. Monduzzi Editore S.p.A., Bologna.
Kim J W, Lee J O. Double blind cross-over clinical study of 830 nm diode laser and 5 years clinical experience of biostimulation in plastic & aesthetic surgery in Asians. Lasers Surg Med. 1998; Suppl. 10: 59.
Kinoshita F et al. Clinical evaluation of low-energy, semi-conductor laser therapy in oral surgery - a double blind study. Josai Shika Daigaku Kiyo (Bulletin of Josai Dental University). 1986; 15 (3): 735-742. (in Japanese with English abstract)
Kosaka R et al. Double blind study of low energy diode laser irradiation for chronic pain disorders. J Phys Med. 1993; 4: 156-160.
Kouno A et al. The evaluation of pain therapy with low powerlaser- Comparative study of thermography and double blind test. Biomedical Thermology. 1993; 13: 102-107.
Lonauer G: Controlled double blind study on the efficacy of HeNe-laser beams versus HeNe- plus Infrared-laser beams in the therapy of activated osteoarthritis of finger joints. Clin Experim Rheuma. 1987; 5 (suppl 2) : 39
Lucas C et al. Low level laser therapy bij decubitus statium III. Rapport Hoegschool van Amsterdam. 1994.
Mach E S et al. Helium-Neon (Red Light) Therapy of Arthritis. Rhevmatologia, 1983; 3: 36. (In Russian)
Mester A: Biostimulative effect in wound healing by continous wave 820 nm laser diode. Double-blind randomized cross-over study. Lasers in Med Science, abstract issue July 1988, No 289.
Miyagi K. Double-blind comparative study of the effect of low-energy laser irradiation to rheumatoid arthritis. In: Current awareness of Excerpts Medica. Amsterdam. Elsevier Science Publishers BV. 1989; 25: 315.
Mokhtar B et al. A double blind placebo controlled investigation of the hypoalgesic effects of low intensity laser irradiation of the cervical roots using experimental ischaemic pain. Proc. Second Meeting of the International Laser Therapy Assn., "London Laser", Sept 1992, p 61. Mokhtar B et al. The possible significance of pulse repetition rate in lasermediated analgesia: A double blind placebo controlled investigation using experimental ischaemic pain. Proc. Second Meeting of the International Laser Therapy Assn, "London Laser" Sept 1992. p 62
Neuman I et al. Low energy phototherapy in allergic rhinitis and nasal polyposis. Laser Therapy. 1996. 1: 37.
Palmgren N et al. Low Level Laser Therapy of infected abdominal wounds after surgery. Lasers Surg Med. 1991; Suppl 3:11.
Poliakova A G., Gladkova N D, Triphonova T.D. Laserpuncture in patients with rheumatoids arthritis. Abstracts of ICMART '97 International Medical Acupuncture Symposium, Nicosia, Cyrprus, March 26-29 1997.
Rochkind S et al. Double-blind Randomized Study Using Neurotube and Laser Therapy in the Treatment of Complete Sciatic Nerve Injury of Rats. Proc. 2nd Congr World Assoc. for Laser Therapy, Kansas City, 1998.
Roumeliotis D et al. 820nm 15mW 4J/cm2, laser diode application in sports injuries. A double blind study. Proc. Fifth Annual Congress British Medical Laser Ass. 1987.
Ryo E et al. Double blind test of low energy laser radiation treatment. Evaluation of effectiveness for shoulder stiffness, arthralgia etc. Pain Clinic. 1986; 7: 185-192. (In Japanese with English abstract)
Saeki N et al. Double blind test for biostimulation effects on pain releif by diode laser. 1989. Laser Surgery; 1066: 93-100.
Sasaki K et al. A double-blind controlled study on free amino acid analysis in CO2 laser burn wounds in the mouse model following doses of low incident infrared (830 nm) diode laser energy. Proc. 2nd Meeting if the Internat Laser Therapy Assn., London, 1992, p.4.
Sato K et al. A double blind assessment of low power laser therapy in the treatment of postherpetic neuralgia. Surgical and Medical Lasers. 1990; 3 (3): 134.
Scudds R A et al. A double-blind crossover study of the effects of low-power gallium arsenide laser on the symptoms of fibrositis. Physiotherapy Canada.1989; 41: (suppl 3): 2.
Taghawinejag M et al. Laser-Therapie in der Behandlung kleiner Gelenke bei chronischer Polyarthritis. Z Phys Med Baln Med Klin. 1985; 14.
Tsurko V V et al. Laser therapy of rheumatoid arthritis. A clinical and morphological study. Ter Arkh. 1983; 55 (7) 97-102. (Russian).
Umegaki S et al. Effectiveness of low-power laser therapy on low back pain. Double blind comparative study to evaluate the analgesic effect of low power laser therapy on low-back pain. The Clinical Report. 1989; 23: 2839-2846. (In Japanese with English abstract)
Vélez-Gonzalez M et al. Treatment of relapse in herpes simplex on labial and facial areas and of primary herpes simplex on genital areas and "area pudenda" with low power HeNe-laser or Acyclovir administred orally. SPIE Proc. 1995; Vol. 2630: 43-50
Willner R et al. Low power infrared laser biostimulation of chronic osteoarthritis in hand. Lasers Surg Med. 1985; 5: 149.
Wylie L et al. The hypoalgesic effects of low intensity infrared laser therapy upon mechanical pain threshold. Lasers Surg Med. 1995; Suppl 7: 9.
Yamaguchi M et al. Clinical study on the treatment of hypersensitive dentine by GaAlAs laser diode using the double blind test. Aichi Gakuin Daigaku Shigakkai Shi - Aichi-Gakuin Journal of Dental Science. 1990; 28( 2): 703-707. (in Japanese)
Yoh K et al. A clinical trial for treatment of chronic pain in orthopedic diseases by using 150 mW diode laser system. Result of double blind test. Chronic Pain; 13: 96-100.(In Japanese with English abstract)
Welcome to the laser-therapy.us research tool. This tool is a searchable collection of technical publications, books, videos and other resources about the use of lasers for photobiomodulation. This tool includes almost the entire U.S. library of medicine research papers on LLLT, videos from Youtube associated with therapy lasers and the tables of contents from laser therapy books. This allows users to search for a keyword or condition and see resources about using lasers to treat that condition. All the resources include links to the original source so we are not making any statement about the use of lasers for treating non-FDA cleared application, we are simple summarizing what others have said. Where every possible, we have included a link to the orginal publication.
Here are some of our favorite queries:
This tool uses a broad match query so:
The results of the search are sorted based on 3 quality factors on a scale of 1 to 10 with 10 being the best score. Originally all the resources were given a 5-5-5 until they could be individually evaluated. These scores are purely opinion and are only used to simplify the rank of the results from more valuable to least valuable. This should not be considered a critique of any work. This system was created to help researchers (including ourselves) find the most usable resources for any cold laser therapy research. The resources are assigned values based on the following 3 factors:
Over the past few years of working with research, we found that a majority of the published resources are lacking in one of these three ranking factors.
The original goal of this research tool was to tie published resources to the protocols in the laser-therapy.us library. This connection allows users to trace each protocol back to a list of resources so the protocol can be researched and improved.
When many of the first research papers were published, the most power laser available for therapy were less than 100mW and many systems had to be pulsed to keep the laser from burning out too quickly. Today, system are available that will deliver up to 60,000mW of continuous output. Because of these power limitation, many early studies were limited to extremely low dosages by today’s standards. It takes a 50mW system 17 minutes to deliver 50 joules at the surface of the skin. If this was spread over a large area of damage or was treating a deeper problem, the actual dosages were much less than 1J/cm2. Today, we know that these dosages typically produce very little or no results.
About 80% of the resources in this database are in the near infrared wavelength. There is also some interest in the red wavelength (600 to 660nm) . Other wavelengths like blue, purple, and green have very little scientific research behind them and have not gotten much traction in the core therapy market with the exception of some fringe consumer products.
This research tool is free to use but we make no claims about the accuracy of the information. It is an aggregation of existing published resources and it is up to the user to determine if the source of the resources has any value. The information provided through this web site should not be used for diagnosing or treating a health problem or disease. If you have or suspect you may have a health problem, you should consult your local health care provider.