Laser Phototherapy, a New Modality in treatment of Long-Term Incomplete Peripheral Nerve Injury: a randomized double-blind placebo-controlled study
Rochkind S, Drory V, Alon M, Nissan M, Ouaknin GE
The authors conducted this pilot study to prospectively investigate the effectiveness of low-power laesr irradiation (780 nm) in the treatment of patients suffering from incomplete peripheral nerve and bachial plexus injuries for 6 months up to several years. Injury of a major nerve trunk frequently results in considerable disability associated with loss of sensory and motor functins. Spontaneous redovery of long-term severe incomplete peripheral nerve injury is often unsatisfactory. A randomized, double-blind, placebo-controlled trial was performed on 18 patients who were randomly assigned placebo (non-acitve light: diffused LED lamp) or low-power laser irradiation (wavelenth, 780 nm; power, 250 mW). Twenty-one consecutive daily sessions of laser or placebo irradiation were applied transcutaneously for 3 h to the injured peripheral nerve (energy density, 450 J/mm2) and for 2 h the corresponding segments of the spinal cord (energy density, 300 j/mm2). clinical and electrophsiological assessments were done at baseline, at the end of the 21 days of treatment, and 3 and 6 months therafter. The laser-irradiated and placebo groups were in clinically similar conditions at baseline. The analysis of motor function during the 6 month follow-up period compared to baseline showed statistically significant improvement (p-0.0001) in the laser-treated group compared to the placebo group. No statistically significant difference was found in sensory function. Electrophsiological analysis also showed statistically significant improvement in recruitment of voluntary muscle activity in ther laser-irradiated group (p- 0.006), compared to the placebo group. This pilot study suggests that in patients with long-term peripheral nerve injury noninvasive 780 nm laser phototherapy can progressively improve nerve function, which leads to signifcant functional recovery.
Photomedicine and Laser Surgery 25:5, 2007; 436-442.