Ultrasound as the first choice for peripheral nerve imaging?

Advances in imaging have made dramatic differences in the diagnosis, understanding and treatment of central nervous system disease, but peripheral nerve imaging remains uncommon. Electrodiagnostic tests, such as nerve conduction studies and electromyographyare the primary means of diagnosis, providing functional but not structural information. Imaging has been limited by the small cross-sectional size of peripheral nerves (e.g., <10mm2 for the normal median nerve), and their often-tortuous anatomical paths. Over the last decade, technological developments in high-resolution ultrasound (US) and magnetic resonance imaging (MRI) have overcome these obstacles, but which method is superior?