Real-world outcomes of intravitreal bevacizumab treat-and-extend for cystoid macular oedema secondary to central retinal vein occlusion

INTRODUCTION: The purpose of this study was to report the real-world treatment outcomes using a treat-and-extend intravitreal bevacizumab protocol in cystoid macular oedema (CMO) secondary to central retinal vein occlusion (CRVO). METHODS: We conducted a retrospective case series of consecutive adult patients with CMO secondary to CRVO who presented between 1st January 2019 and 31st December 2021. All included patients were treated with bevacizumab using a treat-and-extend protocol, were followed up for a minimum of 6 months and had a clinical examination including best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) at every visit. The primary outcome measure was mean change in BCVA. RESULTS: Thirty-three eyes of 33 patients were included in the study. The mean change in BCVA from baseline was + 24.5 (Median 18, SD 21.5) letters, with a mean follow-up duration of 18.5 (SD 8.9) months. The mean number of injections was 9.5 (SD 1.9) in year 1 and 7.8 (SD 2.8) in year 2. 87.9% of patients were still requiring active treatment, with a maximum interval achieved of 4-weekly in 18.2%, 6-weekly in 42.4%, 8-weekly in 6.1%, 10-weekly in 15.2%, and 12-weekly in 6.1%. The mean maximum interval achieved of those requiring ongoing treatment was 6.8 (SD 2.4) weeks. Multiple regression analyses showed that a higher baseline BCVA was negatively associated with mean visual acuity gain (P < 0.001) and positively associated with final BCVA (P < 0.001). CONCLUSION: The use of intravitreal bevacizumab in a treat-and-extend regimen is effective in treating CMO secondary to CRVO, in a real-world setting.