The regional curare test and electrophysiologic diagnosis of myasthenia gravis: further studies.

Five hundred consecutive patients were evaluated for myasthenia gravis with repetitive stimulation of the median and ulnar nerves. Axillary nerve stimulation and repeated stimulation of wrist nerves following regional curare administration to the hand were performed when necessary. Abnormal responses were seen in 95% of 297 patients with generalized disease and in 35% of 54 patients with ocular disease, all of whom were clinically responsive to anticholinesterases. Identical responses were also seen in 32% of 124 patients with possible generalized disease, all of whom lacked clinical responsiveness to anticholinesterases. Abnormalities occurred following regional curare administration in 29% of 224 patients with normal responses during repetitive stimulation alone. This program for evaluating patients with suspected myasthenia gravis continues to be successful, safe, and practical.