Six-month results of intravitreal ranibizumab for macular edema after branch retinal vein occlusion in a single-center prospective study: visual outcomes and microaneurysm formation

PURPOSE: The aim of this study is to report the 6-month results after one intravitreal ranibizumab (IVR) injection followed by pro re nata dosing for macular edema (ME) after branch retinal vein occlusion. PATIENTS AND METHODS: The inclusion criteria included a minimal patient age of 18 years, 20 letters or more best-corrected visual acuity (BCVA) (Early Treatment Diabetic Retinopathy Study [ETDRS] score, 77 letters or less), and central retinal thickness (CRT) of 250 microns or more. The primary outcome measure was the mean BCVA change from baseline at month 6; the secondary outcomes were mean changes in CRT, residual ME, and microaneurysm formation. RESULTS: Twenty patients were enrolled from March 2014 through October 2016 at Nagoya City University Hospital. The baseline mean ETDRS letters and CRT were 63.1 and 500 microns, respectively; mean time from symptom onset to initial therapy was 1.80 months; and mean ETDRS gain and CRT reduction were 15.2 letters and 230 microns, respectively. The percentages of patients with Snellen equivalent BCVAs of 20/40 (70 ETDRS letters) or better and 20/20 (85 ETDRS letters) were 90% and 15%, respectively. Residual ME and microaneurysms were observed in 85% and 35% of patients. Microaneurysm formation was associated with delayed initial therapy. CONCLUSION: Prompt initiation of IVR injection provided a better visual prognosis at month 6 and suppressed the microaneurysm formation.