Clinical applications have been found for lasers in a number of medical and surgical specialties. The high power applications for surgical procedures and hemostasis are well known; however, less dramatic but potentially important biologic effects at powers as low as fractions of milliwatts have also been reported. Although the medical applications of lowpower lasers remain controversial, the clinical use of these devices for a variety of analgesic and wound healing applications is steadily increasing.

Our study was initiated to determine whether low-energy laser stimulation could produce a thermal effect. We used twelve rabbits to examine the tissue temperature change of low-energy infrared laser irradiation. No statistically significant difference between before and after low energy laser irradiation was noted. On the bases of this study, we saw no thermal effect of low-energy infrared laser in skin, subcutaneous tissue, and muscle.