THE VALUE OF HIGH-RESOLUTION SONOGRAPHY A ND MR-IMAGING IN THE DIAGNOSIS AND FOLLOW-UP OF CARPAL-TUNNEL SYNDROME

120 wrists of 105 patients with carpal tunnel syndrome were studied pr eoperatively by high-resolution sonography. Follow-up examinations aft er carpal tunnel release were performed in 72 wrists. In addition, 40 wrists were examined preoperatively, and 20 wrists were examined posto peratively by MR imaging. Based on quantitative analysis of the cross- sectional area and shape of the median nerve and of the palmar bowing of the flexor retinaculum, sonography established the diagnosis in 95 % of cases. MR was superior in the evaluation of mild degrees of media n nerve compression, and in the detection of possible causes of the ca rpal tunnel syndrome, such as synovitis of the flexor tendon sheaths o r ganglionic cysts. In postoperative follow-up, sonographic demonstrat ion of a normally flattened median nerve was an excellent indicator of the successful carpal tunnel release. In 10 patients with persistent or recurrent symptoms after carpal tunnel release, the underlying path ology could be exactly demonstrated by MR.