Ocular hypotony after laser suture lysis following trabeculectomy with mitomycin C.

ABSTRACT

BACKGROUND: To report our experience with laser suture lysis (LSL) following trabeculectomy with mitomycin C, its timing, effectiveness and related complications. METHODS: We retrospectively examined 38 consecutive eyes of 36 patients that underwent LSL following trabeculectomy with mitomycin C. RESULTS: The mean preLSL intraocular pressure (IOP) was 27.0 mm Hg (SD 6.3, range 16-39 mm Hg) and the postLSL IOP (IOP 1 h after the last session of LSL) was 16.0 mm Hg (SD 7.2, range 3-31 mm Hg). Following the LSL in 7 eyes (7 of 38) hypotony (IOP<6 mm Hg, lasting more than 24 h) developed. Two groups were defined. In group I no hypotony was found after LSL and group II went through a period of hypotony. The time interval between surgery and LSL was significantly shorter in group II (mean 5.7, SD 7.5, range 1-19 days), compared to group I ( mean 14.7, SD 13.0, range 1-44 days) (p=0.041). The mean final IOP (IOP measured at the last visit) was 13.3 mm Hg (SD 3.4, range 6-20 mm Hg) and mean follow-up was 6.1 months (SD 3.9, range 2.0-15.2 months). No hypotony was found at final examination. PostLSL IOP and final IOP were significantly lower in group II (p=0.002 and p=0.024 respectively). IOP reduction by LSL was significantly greater in group II (p=0.046). CONCLUSION: LSL is an effective and safe procedure to lower the IOP following trabeculectomy with mitomycin C. Early application of LSL results in lower final IOPs, but has a higher risk of hypotony.