Outcomes of Laser Goniopuncture Following Nonpenetrating Deep Sclerectomy With Mitomycin C: A Large Retrospective Cohort Study

Purpose: To report on the frequency, efficacy, and safety of laser goniopuncture (LGP) in lowering intraocular pressure (IOP) following mitomycin-C-augmented nonpenetrating deep sclerectomy (NPDS) in a large cohort of eyes. Materials and Methods: This is a monocenter database retrospective study. We reviewed records of 350 eyes that underwent NPDS between 2009 and 2015, at the National Ophthalmology Center of XV-XX (Paris, France). We recorded the incidence of LGP, the time between NPDS and LGP, IOP efficacy, and the occurrence of complications. The success of the LGP was defined by an IOP Results: The mean postoperative follow-up period was 19 +/- 15.9 months after the NPDS (range, 6 to 58). LGP was performed in 125 eyes (35.7%) in a mean time after NPDS of 7.4 +/- 7.6 months (range, 1 d to 36 mo). Most LGP procedures were performed during the first year (97 eyes, 77.6%). The survival analysis using the Kaplan-Meier method showed a 50% incidence of LGP by 2 years. The mean IOP before LGP was 23.8 +/- 7.1 mm Hg. LGP resulted in immediate (day 8) and significant IOP lowering by up to 15 +/- 6.8 mm Hg. This decrease was maintained throughout the follow-up period, and the Kaplan-Meier survival success rate at 2 years was 48.9% (95% confidence interval, 39.4-60.8). The most common complication was iris incarceration, which occurred in 22 eyes of 125 LGP (17.6%). Conclusions: Most of the eyes that underwent NPDS may require LGP to reduce the IOP to below the target value. Most often, this procedure was performed in the first year after NPDS (77.6%). LGP lowered IOP<15 mm Hg without any hypotonic medication for at least 2 years in 50% of cases. Goniopuncture is associated with potentially significant complications, of which the most common is iris incarceration. We identified 2 predicting factors for iris incarceration: high IOP before LGP and early LGP after NPDS.