New developments in tube shunt surgery

This article reviews recent studies related to tube shunt surgery.

Medical claims data and surveys of glaucoma surgeons demonstrate that tube shunts are being selected with increasing frequency as an alternative to trabeculectomy. A 5-year pooled analysis of the Ahmed Baerveldt comparison study and Ahmed versus Baerveldt study found a higher rate of surgical success with the Baerveldt glaucoma implant compared with the Ahmed glaucoma valve, but Baerveldt implantation carried a higher risk of hypotony. The primary tube versus trabeculectomy study showed trabeculectomy with mitomycin C produced greater intraocular pressure reduction with fewer glaucoma medications compared with tube shunt surgery as a primary procedure at 1 year, but trabeculectomy had a higher rate of postoperative complications. Adjunctive use of antifibrotic agents may enhance the success of tube shunt surgery. Implantation of a second tube shunt is effective in lowering intraocular pressure following primary tube shunt failure, but good results have also been reported with cyclophotocoagulation. Endothelial cell loss, diplopia, and tube shunt erosion are complications associated with these devices.

The popularity of tube shunts has grown in recent years. Clinical trials and retrospective studies have provided valuable information to guide surgeons in the use of tube shunts. Increased efficacy of glaucoma procedures generally occurs at the cost of a higher risk of surgical complications.