Nitrous oxide-induced myeloneuropathy.

A disabling peripheral myeloneuropathy developed in a health professional with a history of chronic exposure and abuse of nitrous oxide. The distinctive clinical symptoms were radicular sensory loss rather than purely distal, and a "reverse" Lhermitte's sign in the absence of signs of specific spinal cord involvement. The entity of nitrous oxide-induced myeloneuropathy is discussed with a review of the literature, as well as present information regarding the etiology, pathophysiology, symptoms, and treatment. In addition, a case report of nitrous oxide-induced myeloneuropathy is presented.