Can changes on OCTA predict exudative activity on OCT in eyes with neovascular age related macular degeneration? The ACTOR Study.

Abstract

Purpose: To explore the predictability of changes in neovascularization morphology on optical coherence tomography angiography (OCTA) in relation to exudative activity on structural optical coherence tomography (OCT) in eyes with neovascular age-related macular degeneration (nAMD) treated with ranibizumab 0.5 mg.

Methods: Eighty-five eyes of 85 patients with nAMD, diagnosed less than 1 year prior to study entry and treated with ranibizumab 0.5 mg, were included in this longitudinal, prospective study. Included eyes had no exudative activity feature at study inclusion and were treated with ranibizumab 0.5 mg in a PRN regimen for the following 9 months. At each study visit structural OCT and OCTA were performed. Qualitative and quantitative vascular characteristics of macular neovascularization (MNV) were extracted at each visit and correlated with the presence of exudative activity on OCT.

Results: No significant correlation was found between OCTA (neo)vascular characteristics in the absence of exudation with the presence of exudative activity on structural OCT the following month. OCTA's positive predictive value (PPV) for the overall population was 38.87% (confidence interval [33.8%; 44.2%]). The negative predictive value (NPV) of OCTA on the overall population was 60.92%. Inter-observer reproducibility of OCTA assessments Cohen's kappa=0.82.

Conclusion: While OCTA may not be predictive of imminent exudative activity in nAMD, it brings additional information on MNV flow and holds potential as a tool for understanding vascular remodeling. Neovascularization remodeling and exudation may be two separate findings in the disease process in nAMD without necessarily having a causal relationship.