Should patients presenting with transient monocular blindness only be recommended for carotid endarterectomy?
Transient ischemic attack was the entry criterion for 1583 (54.9%) of the patients in the NASCET.24 One-third of these (496 patients) had transient monocular blindness. After medical treatment, the 3-year risk of ipsilateral stroke for patients with at least 50% stenosis and only transient monocular blindness was half that of patients with hemispheric events (Fig. 2). Univariate analyses determined that 6 risk factors in the patients with transient monocular blindness and stenosis of at least 50% more than doubled the risk of stroke: age 75 years or older, male sex, previous history of hemispheric transient ischemic attack or stroke, history of intermittent claudication, 80% to 94% stenosis and absence of collateral vessels. For patients with no risk factors or just 1 risk factor, the 3-year medical risk of ipsilateral stroke was 1.8%; for those with 2 risk factors, it was 12.3%, and for those with 3 or more risk factors, it was 24.2%. The absolute risk reduction at 3 years, in favour
