Early postoperative hypotony after 25-gauge sutureless vitrectomy with straight incisions.

Purpose: To evaluate the rate, duration, and associated complications of postoperative hypotony after 25-gauge sutureless vitrectomy.
Methods: In a retrospective, interventional, institutional case series, 25-gauge sutureless vitrectomy with straight incisions was performed on 111 eyes. Postoperative intraocular pressure (IOP) was measured routinely at 2 hours, 1 day, 1 week, and 1 month. Postoperative IOP, hypotony (IOP, <8 mmHg) rates, and complications associated with low IOP were assessed to determine outcome.
Results: Mean follow-up +/- SD was 5.45 +/- 3.44 months. Mean IOP decreased significantly by 2 hours and on postoperative day 1 (P < 0.001) and increased to preoperative levels at week 1 (P = 0.48). Postoperative hypotony rates were 26.12%, 17.11%, and 8.10% at 2 hours, 1 day, and 1 week, respectively. The ratio of postoperative vitreous hemorrhage in eyes with and without hypotony on day 1 was 2:6 (P = 0.412). Two eyes with macular holes (MHs) filled inadequately with gas endotamponade that remained hypotonic for the first postoperative week underwent reoperation due to unsealed MHs.
Conclusions: Twenty-five-gauge sutureless vitrectomy with straight incisions resulted in a hypotony rate of 26.12% at 2 hours that decreased to 17.11% on day 1 and to 8.10% at week 1 but did not increase the incidence of postoperative complications.