Posterior uveal cleft and hypotony complicating insertion of a fluocinolone acetonide implant

Purpose: To describe posterior uveal cleft and chronic hypotony occurring in association with a fluocinolone acetonide implant (Retisert) that was successfully treated by vitrectomy, removal of the implant, and cryotherapy. Methods: A 57-year-old female patient with idiopathic uveitis, well-controlled with cyclosporine, developed chronic hypotony with maculopathy after insertion of a fluocinolone acetonide implant. Visual acuity in the affected eye was counting fingers, and intraocular pressure was 0 mmHg. Wound leakage, cyclodialysis cleft, and cyclitic membrane were excluded. Ultrasound biomicroscopy demonstrated a posterior uveal cleft at the site of implant, which was presumed to have created a channel for passage of intraocular fluid to the suprachoroidal space. The patient was treated with pars plana vitrectomy, removal of the implant, cryotherapy at the implant site, and intravitreal triamcinolone acetonide injection. Results: The procedure was well tolerated. Intraoperative appearance suggested incarceration of the implant, which did not show on ultrasound biomicroscopy. Intraocular pressure was normalized 5 days after the surgery. Postoperative visual acuity improved to 20/200 at 2 weeks after the surgery and remained stable through 1 year of follow-up. Uveitis remains well controlled with cyclosporine at 1 year after the procedure. Conclusion: Posterior uveal cleft may cause hypotony as a complication of insertion of a fluocinolone acetonide implant. The ultrasound biomicroscopy is a crucial investigation to establish the diagnosis and to exclude other pathologies including cyclodialysis cleft and cyclitic membrane. It may fail to demonstrate incarceration of an implant, however. Proper surgical technique may prevent this complication.