Utility of neuromuscular ultrasound in the investigation of common mononeuropathies in everyday neurophysiology practice.

INTRODUCTION In everyday clinical neurophysiology practice, mononeuropathies are evaluated primarily by traditional electrodiagnostic testing. We sought to assess the additional benefit of neuromuscular ultrasound in this scenario. METHODS All consecutive mononeuropathies undergoing combined ultrasound and electrodiagnostic evaluation over a 23-month period at a single neurophysiology practice were reviewed. Three independent examiners assessed how often ultrasound was: (a) 'contributory' - enabling a definite diagnosis not made by electrophysiology alone and/or impacting on the therapeutic decision, (b) 'confirmatory' of the electrodiagnostic findings, but not adding further diagnostic or therapeutic information, or (c) 'negative' - missed the diagnosis. RESULTS There were 385 studies included. Ultrasound was 'contributory' in 36%, 'confirmatory' in 61% and 'negative' in 3%. DISCUSSION In this study of everyday neurophysiology practice, neuromuscular ultrasound contributed significant diagnostic or therapeutic information in over 1/3 of the investigations for common mononeuropathies. False negative ultrasound studies were uncommon in this setting.