Micropulse Transscleral Cyclophotocoagulation: A Look at Long-Term Effectiveness and Outcomes

Abstract

To investigate the long-term effectiveness of intraocular pressure (IOP) and medication reduction in patients who have undergone micropulse transscleral cyclophotocoagulation (mTS-CPC). Retrospective chart review. A total of 73 eyes of 62 patients treated no more than 1 time with mTS-CPC in a practice in New York City with at least 1 year of follow-up. Treatment was 100 seconds of mTS-CPC with energy titrated on the basis of visual acuity. Paired t test and multivariable analysis were performed with SAS (SAS Institute Inc, Cary, NC). Visual acuity, IOP, medication burden, phthisis, and development of macular edema were followed. Average initial IOP was 25.5±9.4, and average number of initial medications was 3.1±1.1. At 1 year, average IOP was 13.8±7.0 (46% reduction) and average number of medications was 2.5±1.0 (19% reduction). A total of 11 of 15 patients (73.3%) initially taking an oral carbonic anhydrase inhibitor before CPC did not require the oral carbonic anhydrase inhibitor 1 year after treatment. Seventy-six percent of patients obtained at least 20% IOP reduction. Multivariate analysis found IOP reduction was associated with power used and preoperative IOP, whereas medication reduction was associated with initial medication burden. Notably, there was a 57% reduction in IOP at 2500 mW power and a 30% reduction at 2000 mW power. No patients developed macular edema or phthisis from the procedure. Some 18.8% of patients with 20/400 vision or better experienced persistent vision loss of ≥2 lines after the procedure, and 10% of patients with light perception to count finger vision progressed to no light perception (NLP) after the procedure. Of patients with 20/400 vision or better, 12.5% gained ≥2 lines of visual acuity on the Snellen chart at the postoperative year 1 visit. In addition, 15.4% of patients with count fingers to NLP vision improved at the postoperative year 1 visit after treatment. One of 6 patients (16.7%) with NLP gained vision at the postoperative year 1 visit. This study provides evidence that mTS-CPC is a clinically useful procedure associated with good long-term medication burden reduction and IOP reduction that follows a dose-response pattern related to power used.