Efficacy and safety of laser goniopuncture after deep slerectomy

Abstract

Purpose: Successful deep sclerectomy (DS) allows filtration of aqueous humor out of the anterior chamber to the subconjunctival space with formation of a filtration bleb. Sometimes resistance across the trabeculo-Descemet window (TDW) increases with time, and intraocular pressure (IOP) is no longer controlled . Nd:YAG laser goniopuncture (LG) creates several tiny holes in the TDW which could result in an increase of aqueous outflow. The goal of this study was to investigate LG efficacy and safety.

Methods: We conducted a retrospective study on 200 consecutive patients who underwent a DS between 2010 and 2014. The procedure consisted in a deep sclerectomy alone or combined with a phacoemulsification. Mitomycin C and a collagen implant were systematically used. The goniopuncture was performed when IOP increased beyond target IOP.

Results: LG was performed in 42 eyes (21%). The mean interval between LG and DS was 10 ±8 months. The probability of maintaining IOP < 15 mmHg with a 20% decrease from the pre-laser IOP and no further glaucoma procedure or medication was 56 % (95% CI 43-64) at 12 months after LG. The only factor significantly associated with the failure of LG was an iris covering the trabeculo-Descemet's membrane (p < 0.001). Complications observed after LG included peripheral anterior synechiae (11.%), late acute IOP rise (7%) and ocular hypotony (6%).

Conclusions: Laser goniopuncture is an effective procedure to further lower IOP after DS but there are potential complications associated with the procedure.