MRI in unexplained mononeuropathy

Four young patients with severe unexplained progressive mononeuropathy are described. None had a history of known trauma to the affected limb. In addi tion to the standard neurologic examination and electrophysiologic studies (nerve conduction studies and electromyography), all underwent neuroimaging of the involved extremity. In three patients, magnetic resonance imaging r evealed intrinsic abnormalities of the appropriate nerve. The pattern or ab sence of magnetic resonance imaging changes directly influenced decisions a bout surgical exploration of the nerve in all four patients. With the adven t of more sophisticated technology, magnetic resonance neurography has beco me a potent diagnostic tool in the evaluation of disorders of peripheral ne rve and muscle. (C) 2000 by Elsevier Science Inc. All rights reserved.