Perimetric findings in carotid obstructive disease

Abstract

The ocular complications of carotid disease are well known and generally occur in high-degree stenosis (>90%). However, the ocular manifestations of carotid disease, in cases of stenosis >70% but without carotid occlusion, have rarely been studied. Generally, this degree of stenosis is not associated with signs and symptoms of ocular ischemia. The aim of this paper is to study cases of uni- or bilateral stenosis >70%, without signs or symptoms of ischemic ocular syndrome, in order to investigate the ocular functional aspects and to detect the earliest complications to the eye. Thirty-six eyes from eighteen patients with uni- or bilateral stenosis >70%, but without occlusion of internal carotid artery and without any evidence of retinal ischemia, were examined using automated perimetry. Visual field (VF) defects were found in a high percentage of the patients (83%). Mere nerve fiber bundle defects were the most common alterations (53%), followed by mere global reduction of light sensitivity (27%). The high frequency of localized defects in patients without ocular hypertension and glaucomatous optic disc alterations suggests that carotid disease may cause functional damage to the eye. A subclinical chronic ischemic retinopathy may be detected by VF analysis. Probably, it is due to a generalized subclinical chronic ischemic cerebrovascular syndrome. This retinopathy has a multifactorial genesis and, in particular, it might be the result of a decreased arterial perfusion and of microembolization phenomena.