Hypotony management through transconjunctival scleral flap resuturing: Analysis of surgical outcomes and success predictors

Abstract

Aim: To investigate surgical outcomes and success predictors of transconjunctival scleral flap resuturing for the management of hypotony due to overfiltration following trabeculectomy with mitomycin C. Materials and methods: Noncomparative, retrospective, interventional case series in which all Glaucoma patients from two Glaucoma services undergoing transconjunctival scleral flap resuturing between May 2012 and July 2016 were enrolled. Included eyes had to have hypotony [intraocular pressure (IOP) < 6 mm Hg] and/or hypotony maculopathy caused by excessive filtration following trabeculectomy. Key exclusion criteria were wound/bleb leaking and postoperative ocular trauma or infection. Preoperative and postoperative IOP, best-corrected visual acuity (BCVA), fundus imaging, surgical complications, and any subsequent related events or procedures were recorded. Rates of postsurgical hypotony and/or maculopathy resolution and possible success predictors were investigated. Results: A total of 22 patients (22 eyes) with a mean age of 56.4 ± 15.2 years were included. Median follow-up was 245 days [interquartilerange (IR); 120-817 days] and mean IOP was increased from 2.9 ± 1.5 mm Hg (1-6 mm Hg) to 8.5 ± 3.1 mm Hg (2-16 mm Hg) at the last follow-up visit (p < 0.01). Approximately 75% of the cases (16 out of 22) had an IOP between 7 and 18 mm Hg at the end of the follow-up period. Median BCVA (log MAR) at last follow-up visit [0.1 (IR; 0.0-0.3)] was significantly better than preoperative BCVA [0.4 (IR; 0.11.0); p < 0.01]. Hypotony resolved in 81% of the cases, while maculopathy resolution was found in 85% of the cases. Time interval between trabeculectomy and flap resuturing was the only factor significantly associated with patient’s IOP at last follow-up visit (R2 = 0.23; p = 0.036). Success rates (IOP > 6 mm Hg at last follow-up visit) were halved in those left untreated for more than 6 months. No serious adverse event was recorded. Conclusion: Our findings support the use of transconjunctival scleral flap resuturing as an effective and safe alternative for hypotony management due to overflitration following trabeculectomy. As time interval seems to influence the odds of hypotony resolution, early intervention is recommended.