When CMS added CPT 29848 (wrist endoscopy) to the ASC Medicare List in July 2003, it made endoscopic carpal tunnel release a Group 9 procedure - $1,339 by today's unadjusted rate. Open carpal tunnel release (CPT 64721) is a Group 2 procedure, reimbursed at $446, nearly three times less than the endoscopic procedure. It was around this time that more surgeons began discovering the benefits of minimally invasive surgical techniques for carpal tunnel release. The closed-wrist procedure is said to be quicker and cleaner - albeit trickier - to perform, and you can perform it in a procedure room rather than an OR.