Imaging of the Carpal Tunnel

Most patients with symptoms related to the carpal tunnel have idiopathic median nerve compression. Imaging has little role in the care of most cases because steroid injection, therapeutic ultrasound, and surgery have established roles. However, cases with atypical presentation, mass lesions, synovitis, or failed carpal tunnel surgery will benefit from imaging. In this article we review the anatomy of the carpal tunnel, the diseases affecting this region, and then discuss the use of conventional radiographs, computed tomography, ultrasound, and magnetic resonance imaging (MRI), outlining the strengths and weaknesses of each method while listing the signs of disease. We conclude that both ultrasound examination and MRI are powerful and often complementary techniques.