Monocular ischemia--the influence of carotid atherosclerosis versus primary ocular disease on prognosis.

The etiology of monocular ischemia influences the clinical manifestation and long-term neurologic and visual prognosis. During a 10-year period, 140 patients with monocular visual symptoms were evaluated and assigned to a carotid bifurcation occlusive disease group (group I) or a primary ocular disease group (group II) on the basis of angiographic findings and ophthalmologic evaluation. Patients with symptoms secondary to emboli from the carotid bifurcation tended to have a shorter duration of blindness and a lower incidence of permanent blindness initially and during follow-up. The presence of Hollenhorst plaques or retinal artery occlusion did not have any discriminatory diagnostic value since the incidence was similar in both patient groups. Since both primary eye disease and carotid bifurcation occlusive disease can be initially seen as monocular ischemia, carotid angiography and ophthalmologic consultation are necessary to select those patients who will benefit from carotid endarterectomy.