Retinal Nonperfusion in the Posterior Pole Is Associated With Increased Risk of Neovascularization in Central Retinal Vein Occlusion

To review the definition of ischaemic central retinal vein occlusion (CRVO) and stratify the risk of neovascular complication based on wider areas of visible retinal non-perfusion. Retrospective consecutive case series and image analysis study. Setting: Moorfields Eye Hospital, London, United Kingdom. Study Population: Forty-two consecutive treatment-naïve eyes with CRVO imaged with ultra-widefield angiography with a minimum of 12 months follow-up. Observation Procedure: The spatial location and total area of retinal nonperfusion (measured in disc areas, DA) were determined using the validated concentric rings method. The area was corrected for projection distortion. The images were graded by 2 retinal physicians and average measurements used. Main Outcome Measures: Development of neovascular complications. The percentage of eyes developing new vessels increased from none in eyes with less than 10 DA of nonperfusion in total to 14.3% in eyes with 10–30 DA, 20.0% for 30–75 DA, and 80% risk with 75–150 DA of nonperfusion. From 13 (31.0%) eyes with a perfused posterior pole (an area encompassing a 5 disc diameter radius centered at the fovea) and more than 10 DA of nonperfusion isolated in the periphery (beyond the posterior pole), only 1 (7.7%) eye developed new vessels, odds ratio (OR) 0.12 [95% confidence interval (CI): 0.01, 1.03]. Comparatively, for 13 (31.0%) eyes with more than 10 DA of nonperfusion in the posterior pole, 11 (84.6%) developed new vessels, OR 74.25 [95% CI: 9.26, 595.30], P < .001. With ultra-widefield angiography, we have ascertained that posterior pole nonperfusion of more than 10 DA remains the key risk factor for new vessel development compared to areas of nonperfusion confined to the periphery.