Outcomes of laser suture lysis after initial trabeculectomy with adjunctive mitomycin C

To evaluate and compare outcomes of eyes that underwent laser suture lysis (LSL) after initial trabeculectomy with mitomycin C (MMC) to those that did not require such an intervention.

We reviewed the charts of consecutive patients with open-angle glaucoma who underwent initial trabeculectomy with mitomycin C at the Jules Stein Eye Institute between 1998 and 2003. Primary outcome measures were intraocular pressure (IOP) control at 1 year and success rate of trabeculectomy according to following criteria: criteria A, IOP < 21 mm Hg with >or=20% IOP reduction and criteria B, IOP < 15 mm Hg with >or=30% IOP reduction. Kaplan-Meier survival analysis and Cox's proportional hazards regression analysis were used to estimate and determine influence of laser suture lysis on success rates after trabeculectomy.

Laser suture lysis was performed in 95 eyes (84 patients) whereas 146 eyes (121 patients) did not require it. IOP was significantly higher at 12 months in laser suture lysis eyes compared with non-laser suture lysis eyes (12.9 +/- 5.2 mm Hg versus 11.0 +/- 4.1 mm Hg; P = 0.04). Laser suture lysis eyes also had decreased success rates with criteria B (57% compared with 73% at 1 year for non-LSL eyes; P = 0.005). However, only late laser suture lysis (last LSL session >10 days after trabeculectomy) was associated with worse outcome in Cox's proportional hazards model using criteria B (HR = 2.26; P = 0.004). Late hypotony occurred in 4% and 1% of non-LSL and LSL eyes, respectively.

Eyes that undergo laser suture lysis >10 days after initial trabeculectomy with mitomycin C are more likely to have poorer long-term IOP control than eyes not requiring laser suture lysis or eyes undergoing laser suture lysis