RESUMO
Objective To study the diagnostic value of repetitive nerve stimulation test in myasthenia gravis. Method The repetitive nerve stimulation test was performed at axillary nerves, ulnar nerves and facial nerves in 36 patients with myasthenia gravis which treated in our hospital from 1996. 10 to 1999. 10. 108 nerves were tested. Result The RNS test positivity rate of amplitude decrement in 108 nerves was 60. 2% ( 65 nerves). Among them, the highest(77. 8% )positivity rate was deltoid mucle supported by axillary nerve, the lowest(41.7% ) was abductor digiti minimi mucle supported by ulnar nerve. There were 31 cases(86. 1% ) had one or more than one nerves with positive results in 36 patients. The best stimulation frequancy were 3 ～ 5 Hz. Conclusion Stimulate the axillary nerve, facial nerve and ulnar nerve in the same patient, would improve the RNS positivity rate in diagnosis of MG.