OPTICAL COHERENCE TOMOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY BIOMARKERS FOR PREDICTING RESPONSE TO ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION.

Abstract

To identify optical coherence tomography and optical coherence tomography angiography (OCTA) biomarkers associated with persistent retinal fluid in treatment-naïve neovascular age-related macular degeneration after three loading doses of anti-vascular endothelial growth factor therapy. In this retrospective study, 60 patients with treatment-naïve typical neovascular age-related macular degeneration received three monthly intravitreal bevacizumab injections. Four weeks after the third injection, patients were categorized as responders (Group 1, n = 30) if no fluid was seen, or as suboptimal responders (Group 2, n = 30) if fluid persisted. Baseline optical coherence tomography and OCTA parameters were assessed, including central macular thickness, subfoveal choroidal thickness, pigment epithelial detachment height, hyperreflective foci, subretinal hyperreflective material, and macular neovascularization morphology. Optical coherence tomography angiography features were analyzed for loop morphology, branching vessels, peripheral arcades, sea fan pattern, and hypointense halo. Vessel density was quantified in the superficial capillary plexus, deep capillary plexus, and choriocapillaris. No significant differences were found between groups in baseline optical coherence tomography parameters (all P > 0.05). Vessel density in the superficial capillary plexus, deep capillary plexus, and choriocapillaris did not differ between groups. However, OCTA revealed that loop morphology ( P = 0.001), peripheral arcade ( P = 0.009), and branching vessels ( P = 0.032) were more frequent in suboptimal responders. On multivariate regression, only loop morphology remained a significant independent predictor of persistent fluid (OR = 4.36, P = 0.036). Loop-shaped neovascular morphology on baseline OCTA independently predicted poor anatomical response to anti-vascular endothelial growth factor therapy. Identifying such features may support early risk stratification and guide personalized treatment strategies.