Incremental Predictive Value of Month-1 OCT and OCT Angiography for Residual Exudative Activity After Anti-VEGF Loading in Treatment-Naive Neovascular Age-Related Macular Degeneration.

INTRODUCTION During the anti-vascular endothelial growth factor (anti-VEGF) loading phase for neovascular age-related macular degeneration (nAMD), the month-1 follow-up visit represents the earliest standardized imaging time point, yet whether month-1 optical coherence tomography (OCT) and OCT angiography (OCTA) improve prediction of short-term anatomical outcome beyond baseline OCT has not been formally tested. This study quantified the incremental predictive value of month-1 imaging using a nested-model framework that mirrors the sequential clinical workflow.

Methods

This retrospective, single-center cohort included 124 treatment-naive nAMD eyes from 105 patients that completed three monthly anti-VEGF injections and had evaluable baseline, month-1, and month-3 imaging. Poor anatomical outcome was defined as residual intraretinal fluid and/or subretinal fluid at month 3. Nested generalized estimating equation logistic models accounted for inclusion of bilateral eyes and evaluated baseline OCT variables, the incremental contribution of month-1 structural OCT, and the additional contribution of month-1 OCTA-derived macular neovascularization (MNV) area. Discrimination was assessed using area under the receiver operating characteristic curve (AUC), with ΔAUC confidence intervals estimated by patient-level cluster bootstrap.

Results

At month 3, 47 of 124 eyes (37.9%) had residual exudative activity. In the final model, month-1 central subfield thickness (OR 2.065 per 100-µm increase, 95% CI 1.107-3.853), residual month-1 intraretinal fluid (OR 14.623, 95% CI 3.305-64.703), residual month-1 subretinal fluid (OR 6.975, 95% CI 1.963-24.785), and month-1 MNV area (OR 1.130 per 1-mm² increase, 95% CI 1.030-1.240) were associated with poor month-3 anatomical outcome. AUC improved from 0.742 (95% CI 0.658-0.822) with baseline OCT alone to 0.889 (95% CI 0.828-0.940) after adding month-1 structural OCT (ΔAUC 0.147, 95% CI 0.072-0.226), and to 0.908 (95% CI 0.853-0.952) after adding month-1 MNV area. Baseline-to-month-1 quantitative changes were not associated with outcome.

Conclusion

Month-1 structural OCT substantially improved prediction of month-3 residual exudative activity beyond baseline OCT alone, whereas OCTA-derived MNV area contributed modest additional discrimination. These findings identify the first post-treatment imaging visit as an informative point for short-term anatomical risk assessment, but external validation is required before clinical application.