Nonpenetrating filtering surgery.

Trabeculectomy is currently the standard filtration procedure for surgical treatment of glaucoma. This technique has advantages over full thickness procedures but can cause early postoperative complications such as hyphema, shallow or flat anterior chamber, hypotony with the risk of choroidal detachment, and maculopathy. Nonpenetrating procedures are alternatives to trabeculectomy with the advantage of minimizing the risk of postoperative complications related to hypotony. The two major variations of nonpenetrating glaucoma surgery are nonpenetrating deep sclerectomy and viscocanalostomy. Techniques and results are discussed in this paper.