ASRS 2026: Partial EZ attenuation predicts intermediate AMD progression

An imaging biomarker that flags early photoreceptor damage could help retina specialists identify which patients with intermediate age-related macular degeneration (AMD) will progress fastest. Justis Ehlers, MD, FASRS, presented the findings at the American Society of Retina Specialists (ASRS) 2026 annual meeting in Montréal, Canada.

Ehlers, a retina specialist at the Cole Eye Institute, Cleveland Clinic, and colleagues assessed partial ellipsoid zone (EZ) attenuation—outer segment thinning—as a predictor of total EZ loss and geographic atrophy (GA). Total EZ loss serves as an FDA-recognized end point, but identifying eyes that will reach it is difficult; partial attenuation marks earlier outer segment damage tied to function and progression risk.

Study design and findings

The retrospective analysis included 512 eyes with intermediate AMD at baseline and 2-year follow-up. Certified readers segmented spectral-domain optical coherence tomography (SD-OCT) scans, and investigators quantified the partial-total EZ gap as the absolute difference between areas of partial (EZ-RPE thickness ≤20 µm) and total (EZ-RPE thickness = 0 µm) attenuation, then sorted eyes into quartiles.¹

The median baseline gap measured 1.58 mm² in GA progressors versus 0.10 mm² in stable eyes (P <.001). Across quartiles, 2-year total EZ loss rose from 0.00 mm² to 1.14 mm², and GA conversion climbed from 0% to 44%. ROC analyses identified gap cutoffs of 0.70 mm² for predicting rapid total EZ progression (AUC = 0.91; sensitivity = 0.96; specificity = 0.75) and 0.44 mm² for predicting GA development (AUC = 0.85; sensitivity = 0.83; specificity = 0.73).¹

What it means for clinical care

Enriching trials with eyes that carry a wider gap could isolate the patients most likely to progress and speed readouts on whether a therapy protects photoreceptors, Ehlers said. He noted no proven treatment yet exists for intermediate AMD beyond over-the-counter supplementation, which sharpens the focus on surveillance—he now images some higher-risk patients every 3 to 6 months rather than annually. Qualitative biomarkers, from hyperreflective foci to EZ loss, are "already here" for any retina specialist reading an OCT, Ehlers said, but quantitative measurement will require automated, embedded, or cloud-based AI segmentation that is not yet routine.

Reference
1. Ehlers J, Mizuno M, Matar K, et al. Evaluation of partial ellipsoid zone attenuation/outer-segment thinning as a predictor of progression in intermediate AMD. Presented at: American Society of Retina Specialists 2026 Annual Meeting; July 15-18, 2026; Montréal, Canada.