Outcomes of Eyes Lost to Follow-Up in Patients with Central Retinal Vein Occlusion Who are Receiving Anti-Vascular Endothelial Growth Factor Treatment

BACKGROUND: To evaluate the anatomic and functional outcomes in eyes of patients with macular edema (ME) caused by central retinal vein occlusion (CRVO) who were lost to follow-up (LTFU) for more than 6 months following treatment with anti-vascular endothelial growth factor (VEGF) therapy and to determine the predictive factors of visual prognosis in these patients. METHODS: This study was conducted as a retrospective, case series investigation. Patients whose eyes were receiving intravitreal anti-VEGF treatment for CRVO-ME, with the next follow-up visit occurring more than 6 months following treatment were identified. Baseline disease characteristics (at the last visit before being LTFU), cause and duration of treatment interruption, and the resulting disease progression, complications, and outcomes were assessed. Baseline characteristics predictive of visual outcome were also analyzed. RESULTS: This study included a total of 17 eyes of 17 patients. The mean duration of being LTFU was 7.8 ± 2.1 months. On the return visit after being LTFU, 7 of 17 eyes (41.2%) developed neovascular complications. Despite treatment, 12 eyes (70.1%) lost ≥3 best-corrected visual acuity (BCVA) lines, with 2 eyes (11.8%) developing a final BCVA of hand motion or more severe. At the final visit, the mean logarithm of minimal angle of resolution (logMAR) BCVA deteriorated significantly compared to before being LTFU (P < 0.001). The increasing duration of being LTFU is associated with a deterioration of visual acuity prognosis. CONCLUSION: In CRVO-ME patients who are receiving anti-VEGF therapy, unintentional treatment interruptions can cause visually disastrous consequences, including irreversible blindness. Patients who were LTFU for a long period should be strongly warned about their poor visual prognosis.