Release, carpal tunnel: A surgical procedure to relieve pressure exerted on the median nerve within the carpal tunnel (the carpal tunnel syndrome). The median nerve is pinched in the wrist as it passes through the carpal tunnel. The buildup of scar tissue inside the carpal tunnel leads to this problem. Treatment options include: splinting, anti-inflammatory agents, and surgery. The surgical release is performed via a small incision using conventional surgery or a fiberoptic scope (endoscopic carpal tunnel repair).