To understand the relationship between baseline ischemic index (IsI) values on ultra-widefield fluorescein angiography and classification as ischemic central retinal vein occlusion (CRVO).
Single-center retrospective cohort study of CRVO patients imaged using ultra-widefield fluorescein angiography from which IsI values were calculated. An ischemic CRVO was defined as those eyes with an afferent pupillary defect and counting fingers acuity or worse or neovascularization during the first year of follow-up. Logistic regression was performed to characterize the relation between the IsI and clinical outcomes.
Sixty eyes of 60 treatment-naive CRVO patients with baseline ultra-widefield fluorescein angiography and ≥1 year of follow-up were identified. Those with an IsI ≥35% were significantly more likely to have an ischemic CRVO during the first year of follow-up than those with an IsI <35% (83.3 vs. 13.9%, odds ratio 111, P < 0.0001). Baseline and final logarithm of the minimum angle of resolution acuity were worse in eyes with an IsI ≥35% (1.18 vs. 0.46, P < 0.001 and 1.26 vs. 0.45, P < 0.001, respectively) despite similar baseline and final central subfield thickness (P = 0.1–0.23).
A baseline IsI of ≥35% on ultra-widefield fluorescein angiography in eyes with treatment-naive CRVO was sensitive (90%) and specific (92.5%) for classification as an ischemic CRVO during the first year of follow-up.
Fluorescein angiography was previously used to classify a central retinal vein occlusion as ischemic or nonischemic but has since been replaced with functional tests and examination findings. In this study, we examine whether ischemic index values on ultra-widefield fluorescein angiography can help determine whether a central retinal vein occlusion is ischemic or not.
*Department of Ophthalmology, Duke University, Durham, North Carolina; and
†Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.
Reprint requests: Sharon Fekrat, MD, Department of Ophthalmology, Duke University, 2351 Erwin Road, Box 3802, Durham, NC 27710; e-mail: firstname.lastname@example.org
Unrestricted Grant from Research to Prevent Blindness, New York, NY. Heed Ophthalmic Fellowship award to A. P. Finn from Heed Ophthalmic Foundation, San Francisco, CA.
None of the authors has any financial/conflicting interests to disclose.