Morphometric Risk Factors for Drusenoid Pigment Epithelium Detachment Collapse and Retinal Pigment Epithelium Atrophy Expansion

PURPOSE. The purpose of this study was to investigate factors associated with drusenoid pigment epithelium detachment (dPED) growth rate, incidence of dPED collapse, and retinal pigment epithelium (RPE) atrophy enlargement rate following dPED collapse and their impact on visual acuity (VA). METHODS. This was a retrospective longitudinal study on 44 eyes. Serial spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (AF) imaging were performed. Qualitative features and quantitative dPED-related metrics were assessed. The surface-to-volume ratio (S/V) was computed to evaluate dPED shape irregularity. AF imaging was utilized to measure RPE atrophy area in eyes experiencing dPED collapse. Regression models were used to analyze associations among VA, dPED growth rate, and RPE atrophy enlargement rate. Cox regression was used to identify risk factors for dPED collapse. RESULTS. Significant correlations were observed between dPED area, surface, and volume (P < 0.05 for all pairs). The dPED metrics were inversely correlated with the S/V. Incidence of dPED collapse was 22 per 100 eye-years over a mean follow-up of 59 ± 41 months. Eyes experiencing collapsed dPED had worse baseline VA (P < 0.001). RPE hypertransmission (hazard ratio [HR] = 3.68, P = 0.004) and hyper-reflective foci (HR = 3.45, P = 0.02) were risk factors for dPED collapse; a higher S/V ratio was protective (HR = 0.78, P = 0.03). A faster rate of RPE atrophy enlargement was associated with a faster rate of dPED volume increase (r = 0.47, P = 0.02) and worse VA over time (P = 0.02). CONCLUSIONS. Risk stratification in patients with dPED can be aided by identifying risk factors for dPED collapse. Identifying factors associated with RPE atrophy enlargement may have implications for treatment decision making.