Abstract
The utility of low reactive-level GaAlAs semiconductor laser therapy for chronic pain was evaluated in a double-blind clinical trial in 82 patients. Results obtained were also compared to those reported in 8 other double-blind studies found in the literature. Subjective symptoms were improved in 38 of 51 patients (efficacy rate: 75%) in whom a semiconductor laser system (output 100 mW, wavelength 810 nm) was used, while the improvement was noticed in only 4 of 31 patients (efficacy rate: 13%) in whom a sham laser system was employed. The difference in the efficacy rate between the two groups was significant. Skin temperature increased significantly in the laser treatment group. No significant differences were found among the efficacy rates of other low-level laser therapy systems reported on in the literature despite differences in output and wavelength used.
