Retinal Vessel Coronal Displacement in Intermediate Age-Related Macular Degeneration

Introduction: This pilot study aimed to test the feasibility of a novel vectorial image analysis method to quantify coronal microvascular displacement in different retinal plexuses in intermediate age-related macular degeneration (iAMD) over 6 months. Material and methods: A retrospective series of iAMD patients with at least 6-month follow-up was included if they had complete medical records, best-corrected visual acuity (BCVA), optical coherence tomography (OCT), and OCT angiography (OCTA). En-face (coronal) vascular displacement between baseline and 6 months was assessed in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) using the Farneback motion tracking algorithm applied to consecutive OCTA scans. Results: Eighteen eyes of 18 iAMD patients met the inclusion criteria. Average coronal vascular displacement (T₀-T₆) was 13.7 ± 7.72 µm for the SCP, 15.11 ± 10.06 µm for the DCP, and 19.02 ± 12.25 µm for the CC slab. Reticular pseudodrusen (RPD) was associated with greater displacement in the DCP (p = 0.047), but not in the SCP (p = 0.980) or CC (p = 0.473). Quantitative analysis confirmed the highest DCP displacement in RPD eyes (66.7%, p = 0.02), while drusenoid pigment epithelial detachment showed the greatest reorganization in the CC (100%, p = 0.02). Discussion: Retinal vessels undergo significant tangential displacement in iAMD, suggesting a structural reorganization of the microvasculature. Such remodeling may constitute a compensatory response to ultrastructural alterations resulting in ischemia.