Ultrasound Imaging of Median Nerve Conduit in a Patient With Persistent Median Nerve Symptoms

Peripheral nerve injury can be reconstructed using composite polymer nerve autografts, but the sonographic appearance of nerve wraps and conduits have not been well documented. This case report describes the sonographic findings in a 42-year-old woman with bilateral carpal tunnel syndrome status post nerve repair with a conduit. The cross-sectional area of the left median nerve was 24 mm(2) at the carpal tunnel inlet and 5 mm(2) at the forearm. The wrist to forearm ratio was 4.8. There was a hypoechoic space surrounding the nerve that was 1.8 to 1.9 mm thick and bordered by a thin, hyperechoic outer rim. On review of the operative record and consultation with her surgeon (DR), it was determined that this represented the 2-mm nerve wrap used in the last surgery. Inclusion of these structures with the median nerve measured a total area of 52 mm(2) at its maximum. In describing this image, we hope to lay the foundation for describing the sonographic appearance of peripheral nerve repair.