Efficacy of Trabeculectomy Combined with Limited Deep Sclerectomy versus Trabeculectomy Alone: A Randomized Controlled Trial.

Precis Addition of limited deep sclerectomy to conventional trabeculectomy enhances success rate, especially in pseudophakic eyes. Purpose To evaluate the efficacy of limited deep sclerectomy (LDS) in enhancing the IOP lowering outcomes of trabeculectomy. Design Parallel arm, single-masked, randomized controlled trial. Methods Sixty-eight eyes of 68 patients with moderate to advanced primary open angle glaucoma or primary angle closure glaucoma (PACG) with pseudophakia were recruited at a tertiary eye care centre in Northern India and randomized into two groups. Thirty five eyes in group 1 underwent trabeculectomy alone and 33 eyes in group 2 underwent trabeculectomy with LDS. All cases were augmented with low dose subconjunctival mitomycin-C (0.1▒mg/mL for 1▒min) in both groups.The primary outcome measure was intraocular pressure (IOP) and success rates were calculated for IOP ≤18/15/12▒mmHg and ≥5▒mmHg. Secondary outcome measures included evaluation of bleb morphology, presence of intrascleral aqueous lake and supraciliary flow on ultrasound biomicroscopy. Results Mean postoperative IOP at 12 months was 13.4±1.83▒mm Hg in Group 1 and 12.5±1.67▒mm Hg in Group 2 (P=0.04). For IOP cut off ≤15▒mmHg, absolute success was noted in 11 (31.4%) and 22 eyes (66.6%) in group 1 and 2, respectively (P=0.004). At 12 months the intrascleral lake was detected in 2 (6%) eyes in group 1 and 9 (29%) eyes in group 2 (P=0.02). The supraciliary flow was detected in two eyes (6.2%) in group 2 and none in group 1, at 12 months (P=0.02). In the Cox proportional hazard model, trabeculectomy with LDS was associated with a lower rate of failure (Hazard ratio: 0.32, 95% CI: 0.13-0.75, P=0.009). Conclusion The addition of LDS to trabeculectomy achieved lower mean IOP and higher success rates at 12 months, compared to trabeculectomy alone.