Comparison between pars plana and anterior endoscopic cyclophotocoagulation for the treatment of glaucoma

Importance: This is the first study to compare the efficacy and safety of endocyclophotocoagulation (ECP) via pars plana (ECP-plus) with ECP via limbus (anterior ECP) for treating glaucoma. Background: There is no direct comparison of treatment outcomes between ECP-plus and anterior ECP. Design: Retrospective study. Participants: Fifty-four consecutive patients. Methods: Fifty-eight eyes from 54 consecutive patients underwent anterior ECP (33 eyes) or ECP-plus (25 eyes) with 2-year follow-up. Linear mixed model was used to analyse the surgical outcomes. Main Outcome Measures: Intraocular Pressure (IOP) was the primary outcome. Secondary outcomes were best-corrected visual acuity, number of glaucoma medications, complications and success rate. Results: Compared to anterior ECP, patients in the ECP-plus group had lower IOP (estimate of effect size [EES] = −3.7 mmHg, P = 0.023) and used fewer number of glaucoma medications (EES = −1.11, P = 0.003), after adjusting for degrees of treatment, preoperative IOP, and presence of combined ECP and phacoemulsification procedure. Patients with ECP-plus achieved a higher success rate at 2 years postoperatively (80% vs 33.3%, P < 0.001). The decrease in IOP between the preoperative and last follow-up visit was greater in the ECP-plus group compared to the anterior ECP group (14.3 mmHg (52%) vs 5.2 mmHg (24%), P = 0.001). There was no significant difference in complication rates between the two groups (28% vs 33%, P = 0.561). Conclusions and Relevance: Anterior ECP and ECP-plus have a similar safety profile, and ECP-plus may offer superior IOP control for the management of glaucoma.