Abstract
Purpose :
Central retinal artery occlusion (CRAO) has known systemic risk factors, and the majority of cases are embolic. Previous cadaveric studies have identified patterns of branching of the ophthalmic artery in relation to its position to the optic nerve. These may suggest a relationship between the position of the ophthalmic artery relative to the optic nerve and risk of CRAO. Specifically, when the ophthalmic artery crosses over the optic nerve, the first branch is a common trunk supplying the CRA and the medical posterior ciliary artery (MPCA), whereas the CRA arises alone when the ophthalmic artery crosses under the optic nerve. Combined CRA-MPCA occlusions are exceedingly rare compared to CRAO; we thus hypothesized that the ophthalmic artery is more likely to cross below the optic nerve in eyes with CRAO compared to eyes without. Here, we evaluated the anatomic position of the ophthalmic artery relative to the optic nerve and risk of CRAO development to determine if an anatomic risk factor may exist for development of CRAO.
Methods :
This is a case-control study. Cases included eyes with a CRAO diagnosis and controls included eyes without a CRAO diagnosis; both groups had brain neuroimaging (computed tomography or magnetic resonance angiography). Two neuroradiologists reviewed the brain neuroimaging for cases and controls and determined if the ophthalmic artery crossed over or under the optic nerve; only eyes in which there was agreement were included. The significance of association was determined by Type III ANOVA tests p-values less than 0.05 as statistically significant in the mixed effect logistic regression model.
Results :
A total of 122 eyes from 61 patients (21 with CRAO, 40 without) were included. 33 patients (54.1%) were male. Mean age was 64.4 years (standard deviation (SD) 11.9). No significant association was noted between the position of the ophthalmic artery relative to the optic nerve and diagnosis of CRAO (p=0.50). An age-adjusted multivariate logistic regression with random effects also did not exhibit a significant association with CRAO diagnosis (p=0.48).
Conclusions :
The anatomic position of the ophthalmic artery relative to the optic nerve is not a significant risk factor in the development of CRAO. This result suggests factors beyond embolic physiology alone - namely, the propensity of emboli to lodge at arterial branching points - are involved in CRAO development.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.