Surgical management of hypotony owing to overfiltration in eyes receiving glaucoma drainage devices.

PURPOSE: To assess rates of surgical revision of glaucoma drainage devices (GDDs) from hypotony owing to overfiltration and its management.

DESIGN

Retrospective case series.

METHODS

Demographic characteristics, type of GDD implanted, type of surgical revision, and outcomes were obtained from the charts of patients undergoing GDD implantation and > or = 1 subsequent GDD revision in 2002 to 2006. All surgical revisions performed owing to hypotony from overfiltration in the absence of a wound leak were identified.

RESULTS

Of 1292 eyes undergoing GDD implantation, 21 (1.6%) developed hypotony owing to overfiltration requiring surgical revision: 15 eyes of 488 (3.1%) with a Baerveldt implant and 6 of 804 (0.7%) with an Ahmed (P=0.002). When including primary and secondary revisions, 6 of 12 eyes (50%) treated by using polyglactin suture ligation were successful (did not require additional surgery) compared with 8 of 10 (80%) undergoing suture ligation using prolene.

CONCLUSIONS

Hypotony owing to overfiltration is an uncommon GDD-surgery complication. Understanding how to manage patients who develop this complication can improve patient outcomes.