Incidence of ocular ischemic syndrome in patients with asymptomatic severe internal carotid artery stenosis.

Objectives: To evaluate the incidence of ocular ischemic syndrome (OIS) in patients with asymptomatic Severe Internal Carotid Artery Stenosis or occluded (ipICA-SO).

Design and methods: 260 patients with ipICA stenosis ≥ 70%, 120 patients with ipsilateral OIS, and 140 with normal ocular condition. The logistic regression analysis was conducted to establish risk prediction models of OIS/Neovascular-OIS/Chronic-OIS for patients with ipICA-SO. The area under the receiver operating characteristic curve (AUC) was used to test the application value of the prediction models.

Results: In ipICA-SO patients, OIS patients showed significantly higher incidence of ipICA occlusion (p < 0.001), plaque unstable (p < 0.001 ipsilateral/contralateral) or plaque located at both the primary and siphon section (p = 0.004 in ipsilateral), contralateral ICA or anterior/middle cerebral artery severe stenosis (p = 0.001, 0.016, 0.040, respectively), and ipsilateral OphAr low /reflux blood flow (p < 0.001). The hypertension was significantly higher in the control group (p = 0.002). The AUC of the prediction model of OIS was 0.834. Diabetes mellitus (DM) and OphAr reflux blood flow are risk factors for Neovascular-OIS. The AUC of Neovascular-OIS was 0.724. Chronic progress is likely in OIS patients with ipICA occlusion and DM. The AUC of Chronic-OIS was 0.673.

Conclusions: The ipICA-SO patients without sufficient collateral flow are more likely to develop OIS. IpICA-SO patients with hypertension had a lower risk of developing OIS. Neovascular was commonly found in OIS patients with DM and reversed OphAr blood flow. Chronic OIS was associated with ipICA total occlude and DM.