Abstract
Purpose :
Incomplete and complete Retinal Pigment Epithelial (RPE) Outer Retinal Atrophy (iRORA and cRORA) are consensus terms published by the Classification of Atrophy Meeting (CAM) group to describe OCT based retinal changes associated with development of atrophy in eyes with Age Related Macular Degeneration (AMD). This is a retrospective cohort study to identify the prevalence of iRORA and the risk of progression to late AMD, particularly cRORA.
Methods :
Participants enrolled in the Age-Related Eye Disease Study 2 (AREDS2) at Year 5 and Year 10 study visits from a single center, the University of Wisconsin were included. SDOCT scans (97 B scans each) of 102 eyes of 65 patients with AMD were evaluated by two graders. Disagreements were adjudicated by a senior grader. Year 5 SDOCT scans and color photographs were evaluated to exclude eyes with late AMD (cRORA and neovascular AMD). cRORA was defined using the CAM critera as follows: choroidal hypertransmission > 250 µm, attenuation or disruption of RPE, and photoreceptor degeneration, that is, subsidence of the inner nuclear layer (INL) and outer plexiform layer (OPL), presence of a hyporeflective wedge in the Henle fiber layer (HFL), thinning of the outer nuclear layer (ONL), disruption of the external limiting membrane (ELM) or disintegrity of the ellipsoid zone (EZ), and when these criteria do not meet the definition of cRORA or RPE tear. 76 eyes of 48 subjects with intermediate AMD which remained were evaluated for iRORA, which was identified if all three above criteria for cRORA were met but the size was < 250 µm. Also, the type of photoreceptor degeneration, when present, was documented. Subsequently, 10-year scans were graded and eyes with late AMD were identified.
Results :
At year 5, iRORA was present in 11 eyes (14.5%). Absence of the ELM was the most commonly seen feature of photoreceptor disruption (100%). 20 eyes (26.3%) at year 10 follow up had cRORA. Of the eyes with iRORA at year 5, 5 (45.5%) developed cRORA at year 10. For eyes with iRORA, the odds ratio for developing cRORA was 2.17 (95% CI 0.52, 9.08; p=0.28).
Conclusions :
iRORA represents a stage before development of irreversible endpoints such as geographic atrophy (GA). Long term studies with larger sample size are required to understand this important new step in AMD classification. It remains to be studied if some OCT related features of iRORA may be more predictive of progression than others.
This is a 2021 ARVO Annual Meeting abstract.