Electrodiagnostic evaluation of patients with myasthenia gravis and related disorders.

The technique of repetitive nerve stimulation was developed as a means of confirming a diagnosis of MG. The application of this test in the clinical evaluation of patients with muscle weakness has identified other disorders of neuromuscular transmission such as LEMS, infantile botulism, and several forms of congenital myasthenia. Repetitive nerve stimulation to several different nerves, before and after exercising the muscles, usually permits identification of disorders of neuromuscular transmission more readily than very detailed study of one muscle. There are other useful electrodiagnostic tests, but in most cases, repetitive nerve stimulation of weak muscles will permit the identification of a disorder of neuromuscular transmission.