Predicting directional macular atrophy progression using angular plot analysis of DARC

Background: To evaluate Detection of Apoptosing Retinal Cells (DARC), Ellipsoid Zone (EZ) loss, EZ–Retinal Pigment Epithelium (RPE) difference, and Hyperreflective Foci (HRF) as predictors of directional macular atrophy (MA) growth in age-related macular degeneration (AMD) using a novel angular plot analysis.

Research design and methods: Seven eyes with MA from the Phase 2 DARC study (ISRCTN10751859)were identified according to strict criteria. MA growth was measured using sequential follow-up retinal scans. EZ loss, EZ–RPE difference, HRF density, and DARC activity were quantified around the MA center, and angular plots were generated in 1-degree sectors of a full circle centered on the MA lesion.Directional associations with subsequent MA growth were assessed using Spearman’s rank correlation.

Results: Over a mean follow-up of 48.4 months, DARC demonstrated a significantly stronger correla-tion with future MA growth than EZ loss (p = 0.0191), EZ-RPE difference (p = 0.0267) and HRF density(p = 0.0252).

Conclusions: In this small preliminary study, DARC appears to provide the strongest, most consistent predictor of directional MA growth. Angular plot analysis provides a robust approach for evaluating progression and supports DARC as a promising biomarker for identifying patients at high risk of MA expansion