Treatment Outcomes of Retinal Vein Occlusion in Clinical Practice in Nepal

Abstract

Background: This study evaluated the treatment outcomes of retinal vein occlusion (RVO) in a routine clinical practice in Nepal. Methods: This was a retrospective analysis of observational data of patients with RVO who attended the retina clinic of the Tilganga Institute of Ophthalmology from 1 November 2017 to 31 October 2018. The main outcome was the mean change in visual acuity (VA) at 12 months from the start of treatment. Other outcomes of interest were the mean change in central subfield thickness (CST) and the number of treatments over 12 months. Results: A total of 99 eyes (of 99 patients) with RVO (60 - branch RVO [BRVO] and 39 - central RVO [CRVO] were available for the analysis. Eyes with CRVO had worse VA and CST at baseline. Eyes in both groups were similar for age, associated factors for RVO, duration of vision loss and the presence of ischemia at baseline. The mean (95% Confidence Interval [CI]) VA change at 12 months for BRVO was -0.35 (-0.46, -0.23) logMAR (p < 0.001) from a mean (SD) of 0.75 (0.42) logMAR at baseline with 63% achieving VA < 0.3 logMAR while for CRVO it was -0.35 (-0.46, -0.23) logMAR (p = 0.19) from 1.13 (0.61) logMAR at baseline and VA < 0.3 logMAR in 36%. The mean (95% CI) change in CST over 12 months was -114 (-189, -40) µm (p = 0.003) from a mean (SD) of 423 (151) µm at baseline for BRVO and -184(-276, -91) µm (p < 0.001) from 519 (213) µm for CRVO. Patients in both groups received a median of 2 bevacizumab injections over 12 months. Around 37% eyes were lost before 12 months’ observation. The mean VA and CST trajectory in these eyes at their last visit was similar to those that completed 12 months. Conclusion: The outcomes of RVO are inferior and the number of treatments over the 12 months fewer than those of clinical trials and other reports from routine clinical practice. Future studies to identify the barriers for undertreatment in our practice are warranted to improve the treatment outcomes.