Background and purpose: Chronic ocular ischemia is a rare form of ischemia of the eye in patients with carotid artery occlusion (CAO). The early and often asymptomatic stage of chronic ocular ischemia is referred to as venous stasis retinopathy (VSR). The aim of this study was to gain insight into the prevalence, cause, and outcome of VSR in patients with symptomatic CAO.
Methods: In 110 patients with symptomatic CAO, we prospectively investigated the frequency of VSR, the association between the presence of VSR and impaired cerebral blood flow, and the proportion of patients who developed clinically manifest chronic ocular ischemia with ischemia of the anterior eye segment or blindness.
Results: At study entry, VSR was found in 32 patients (29%; 95% CI, 21 to 38), particularly in those with symptoms classically associated with a hemodynamic cause, such as limb shaking (relative risk, 2.4; 95% CI, 1.0 to 5.9). Patients with VSR had lower pulsatility indexes in the ophthalmic artery in case of reversed flow, lower cerebral CO2 reactivity, and lower cerebropetal blood flow than patients without VSR. On follow-up (mean, 29 months), clinically manifest chronic ocular ischemia developed in 4 patients (annual rate, 1.5%; 95% CI, 0.4 to 3.8); it tended to occur more often in patients in whom VSR was present at study entry (relative risk, 7.3; 95% CI, 0.8 to 68).
Conclusions: One third of patients with symptomatic CAO has VSR on ophthalmoscopy. VSR is associated with an impaired flow state of the brain. Development of clinically manifest chronic ocular ischemia is rare.