Embolism from atherosclerotic plaques of the carotid bifurcation is being recognized as a frequent cause of occlusion of intracranial arteries producing transient ischemic attacks or strokes. Fifty carotid bifurcation lesions were performed in an attempt to establish roentgenographic criteria for ulceration, and judge the accuracy of radiologic diagnosis of ulceration. The preoperative radiologic impression of the carotid lesion was compared with the actual appearance of the lesion as seen at operation and pathologic examination. Sixteen of the lesions contained small areas of ulceration and 22 contained large ulcers, for an overall incidence of ulceration of 76%. The accuracy of the radiologic diagnosis of ulceration was 86%.
Four criteria were established for radiologic ulceration. These are (1) a penetrating niche; (2) irregularity of the silhouette of the artery; (3) delayed washout of contrast medium in a segment of artery between areas of stenosis; and (4) a well-circumscribed double density of contrast medium superimposed on the artery.