Use of sonography in carpal tunnel syndrome surgery. A prospective study.

The diagnosis of carpal tunnel syndrome (CTS) is mainly based on the characteristic symptoms and confirmed with nerve conduction studies. Sonography can provide measurements of the increased cross-sectional area of median nerve. The use of sonography was evaluated for the diagnosis and postoperative follow up of 48 wrists in 26 consecutive patients with CTS. Clinical evaluation and sonography were effective for the diagnosis in 40 wrists. Nerve conduction studies were needed in eight wrists, because of the decrease in cross-sectional area of the nerve as a result of degenerative changes. After 3 months, sonography detected statistically significant decreases in the cross-sectional areas of the median nerves. The sonographic studies were well tolerated by all patients. Sonography was both time-saving and cost-effective.