Carotid plaques and retinal emboli: a clinical, angiographic and morphological study.

The angiographic criteria for the significance of a carotid lesion and the contribution of embolic versus haemodynamic factors in stroke pathogenesis are currently unresolved. This study evaluated correlations between the clinical features, presence of retinal emboli, angiographic appearance of the carotid bifurcation and morphology of the surgically excised plaque in 32 consecutive patients with symptomatic carotid lesions. Retinal emboli were found in 22% of patients, including some without a history of amaurosis fugax. The carotid plaques were complicated by ulceration, intraplaque haemorrhage and/or intraluminal debris in 91% of cases. The degree of carotid stenosis seen at operation correlated well with the angiographic estimate. Plaque complications could not be accurately predicted angiographically, however. The high frequency of plaque complications, and the presence of retinal emboli, suggested that embolisation was the likely pathogenetic mechanism of stroke in most of these patients.