Abstract
Purpose :
To better define what constitutes an ischemic central retinal vein occlusion (CRVO) based on ischemic index values on ultra-widefield fluorescein angiography (UWFFA).
Methods :
We performed a retrospective cohort study of all CRVO patients imaged with UWFFA at our institution between January 2009 and July 2016. Ischemic index values were calculated using mid-phase UWFFA images of the involved eye. An ischemic CRVO was defined as those eyes with an afferent pupillary defect (APD), anterior or posterior segment neovascularization, or counting fingers acuity or worse over the course of follow-up. Baseline characteristics, OCT parameters and visual outcomes were compared in eyes with an ischemic index ≥35% and <35%. Logistic regression was performed to characterize the relation between the ischemic index, visual outcomes and development of an ischemic CRVO.
Results :
54 eyes of 54 treatment naïve CRVO patients with UWFFA at the initial visit and at least 1 year of follow-up were identified. The mean ischemic index was 22.67% (Range 0-60.28%; SD 22.68%). 18 patients (33.3%) had an ischemic index ≥35%. Baseline characteristics such as age, sex, race and CRVO risk factors were similar between the groups. Those with an ischemic index ≥ 35% were significantly more likely to have an ischemic CRVO during follow-up than those with an ischemic index <35% (83.3% vs 13.9%, OR 24.1, p<0.0001). Baseline and final logMAR acuity was worse in those eyes with an ischemic index ≥35% (1.26 vs 0.50, p<0.001; 1.20 vs 0.55, p=0.005 respectively). Additionally, patients with an ischemic index ≥35% were more likely to have final acuity of 20/200 or worse (66.7% vs 22.2%, OR 5.7, p = 0.005). Baseline and final central macular thickness (CMT) was similar between the groups (p=0.28-0.78).
Conclusions :
Among patients with treatment naïve CRVO, a baseline ischemic index of ≥35% on UWFFA was strongly associated with classification as an ischemic CRVO over long-term follow-up. Additionally, a baseline ischemic index of ≥35% was associated with poorer presenting and final acuity despite similar baseline and final CMT on OCT.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.