顔面神経麻痺における筋電気刺激の効果

抄録

Electrical stimulation of the affected muscle is one therapeutic scheme for treatment of severe facial palsy, although the efficacy of electrical stimulation has not been clearly demonstrated. The purpose of this study was to determine if and how electrical stimulation of the mimetic muscle influences muscle atrophy and regeneration of the innervating nerve in the course of facial paralysis. Facial palsy was induced in guinea pigs by clamping the bilateral facial nerves for 15 minutes. Repeated electric stimulation of 0.1ms in duration (20Hz) and 10V in strength, for 20 minutes a day, was administered to the orbicularis oculi muscle of the left side. Electrical stimulation was administered in the three ways; daily for 20 days during the whole course of facial palsy (group A), daily for days 1-10 after paralysis (group B) and daily for days 11-20 (group C). Electromyographical and histochemical findings showed that the muscle atrophy was prevented in all groups irrespective of the timing of electrical stimulation, however, nerve regeneration was inhibited in groups A and C. These results suggest that electrical stimulation of the muscle should not be conducted after the 10th day of palsy when the innervating nerve has reached the affected muscle.