Long-term Clinical Outcomes of Acute Zonal Occult Outer Retinopathy in a Tertiary Referral Center

Purpose: To characterize the clinical features, multimodal imaging findings, and long-term visual outcomes of patients with acute zonal occult outer retinopathy (AZOOR) in a single-center cohort. Methods: This retrospective cohort study included 34 eyes of 26 patients with AZOOR who were referred to a tertiary referral center between January 2015 and December 2023. Best-corrected visual acuity, fundus photography, fundus autofluorescence, optical coherence tomography (OCT), Humphrey 24-2 visual field examinations were conducted during the initial and final follow-up visits. Results: The mean follow-up duration was 50.8 ± 37.9 months (range, 14-138 months). Of these 26 patients, 24 (92.3%) underwent systemic treatment. Disruption of the outer nuclear layer and ellipsoid zone (EZ) was commonly noted at baseline. In contrast, the retinal pigment epithelium was relatively preserved. During follow-up, the proportion of eyes with intact EZ increased from 26.5% to 41.2%, although this change was not statistically significant (p = 0.065). EZ restoration was observed in five eyes. Visual acuity and visual field indices remained largely unchanged during follow-up. Conclusion: In this cohort, patients diagnosed with AZOOR demonstrated heterogeneous long-term structural and functional outcomes. Although partial recovery of outer retinal structures was observed in some patients, visual impairment often persisted despite structural improvement. Long-term multimodal follow-up may therefore be important for evaluating disease progression and prognosis.