Cyclophotocoagulation in the Control of Glaucoma in Patients with the Boston Keratoprosthesis Type 1

Purpose: To evaluate the outcomes of transscleral cyclophotocoagulation (CPC) in the control of glaucoma in eyes with a Boston keratoprosthesis (KPro) type 1. Methods: This study is a retrospective case series of patients who have undergone at least 1 CPC treatment after KPro implantation. Eighteen eyes of 17 patients were included. Intraocular pressure (IOP) (assessed by digital palpation) and the number of classes of glaucoma medications were recorded at 1 week, 1 to 3 months, 4 to 6 months, and 1 year postoperatively. Optic nerve status, visual field parameters, and perioperative and postoperative complications were recorded. Results: Twenty-one CPC sessions were administered overall. Seven eyes (39%) had IOP , 20 mm Hg preoperatively, and this increased to 15 eyes (83%) at the 1-year postoperative follow-up. The mean number of glaucoma medications used was 3.9 preoperatively and did not change significantly after treatment. Seven eyes (39%) had glaucoma progression despite CPC treatment. Three eyes (17%) initially responded to CPC but later failed at 3, 6, and 12 months. Two of them responded to repeat CPC, and 1 continued to progress despite retreatment. Two eyes (11%) developed early postoperative hypotony, 1 eye (6%) developed cystoid macular edema, 1 eye (6%) developed bacterial endophthalmitis with subsequent enucleation, and 1 eye (6%) lost light perception because of glaucoma. Conclusions: CPC was useful to control IOP in some KPro eyes with refractory glaucoma, although it did not significantly reduce concurrent medical therapy. In addition, caution must be taken because microbial infection can occur after CPC because of the lack of biointegration between the host cornea and the device.