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Updated: Jan 27, 2026

Optimization of the Retinal Vein Occlusion Mouse Model to Limit Variability
Published on: August 6, 2021
Disorganization of Retinal Inner Layers and Ellipsoid Zone Disruption Predict Visual Outcomes in Central Retinal Vein
Errol W Chan1, Mohab Eldeeb2, Vincent Sun3
1Department of Ophthalmology, McGill University, Montreal, Canada; Montreal Retina Institute, Montreal, Canada.
Purpose:
To assess the associations and predictive value of spectral-domain (SD) OCT inner and outer retinal structural parameters and visual acuity (VA) outcomes in macular edema (ME) secondary to central retinal vein occlusion (CRVO).
Design:
Retrospective, longitudinal cohort study.
Participants:
Eighty-four patients with ME secondary to CRVO receiving pro re nata anti-vascular endothelial growth factor (VEGF) therapy at 3 tertiary-level retina referral centers.
Methods:
In all participants, VA, demographic and clinical parameters, and SD OCT images from baseline, 3 months, and 12 months were reviewed. Spectral-domain OCT-based morphologic features in the 1500-μm foveal zone were analyzed by masked graders for disorganization of the retinal inner layers (DRIL), ellipsoid zone (EZ) and external limiting membrane disruption, cone outer segment tip (COST) visibility, cysts, subretinal and intraretinal fluid, and epiretinal membranes.
Main Outcome Measures:
Spectral-domain OCT-based retinal structural parameters and VA outcomes.
Results:
In multivariate analyses adjusting for baseline VA, worsening VA over 1 year was associated with 1-year increases in DRIL (point estimate, 0.06 per 100 μm; P < 0.001) and EZ disruption (0.07 per 100 μm; P = 0.023), but decreased COST visibility (-0.09 per 100 μm; P = 0.018). A 3-month increase in DRIL (0.05 per 100 μm; P = 0.003) and EZ disruption (0.10 per 100 μm; P < 0.001) were the only factors predicting VA worsening over 1 year, after controlling for baseline VA. A multivariate model including 3-month evolution in DRIL, EZ disruption, and VA accounted for 86.3% of variability in 1-year VA change. Absolute differences between predicted and actual 1-year VA were within 2 lines in 80.9%. When DRIL increased by 250 μm or more over 3 months, no eyes showed VA improvement of 1 line or more in 1 year. When EZ disruption decreased by 250 μm or more over 3 months, no eyes worsened by 1 line or more over 1 year.
Conclusions:
Early recovery over 3 months in both DRIL and EZ parameters are key drivers of 1-year VA outcomes. Predictive models incorporating 3-month changes in DRIL and EZ disruption support their usefulness as potential robust determinants of future VA.
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