Revision of dysfunctional filtering blebs by conjunctival advancement with bleb preservation.

PURPOSE: To assess the outcome of advancing a conjunctival flap with preservation of the bleb in eyes undergoing filtration bleb revision after trabeculectomy.
METHODS: A retrospective review of cases from a university-based referral practice identified 30 eyes of 30 patients that had undergone bleb revision after trabeculectomy by advancement of a conjunctival flap over the de-epithelialized bleb. Success was defined as resolution of the bleb-associated complication necessitating the revision (leak, hypotony, discomfort) with maintenance of intraocular pressure greater than or equal to 6 and less than or equal to 21 mm Hg without glaucoma medications. Qualified success met the above criteria but with the use of glaucoma medications. Summary data including visual acuity were obtained.
RESULTS: On the 30 eyes, 30 conjunctival advancement procedures were performed. Seventeen were for bleb leaks, 10 for prolonged hypotony without bleb leak, and three for dysesthetic bleb. Eighteen eyes (60%) were classified as a complete success and 24 eyes (80%) achieved at least a qualified success. Cumulative probability of at least qualified success was 77% at 2 years. Failures included inadequate intraocular pressure control (one eye), recurrent bleb leak (three eyes), and hypotony without bleb leak (two eyes). The mean preoperative intraocular pressure for all eyes increased from 4.4 +/- 3.7 mm Hg to 12.3 +/- 6.2 mm Hg (P <.00001) at the final visit with a mean follow-up of 18.9 +/- 15.5 months. Visual acuity improved or remained within 1 line of preoperative acuity in all but five patients. Complications included two patients with mild ptosis and four patients with hypertropia.
CONCLUSION: Advancement of a conjunctival flap with preservation the preexisting bleb often provides successful resolution of bleb-associated complications.