Diagnosis of internal carotid artery occlusion by dynamic computed tomography.

To evaluate internal carotid artery occlusion noninvasively by means of computed tomography (CT), dynamic CT studies with intravenous bolus injection of contrast medium were performed in 13 patients with hemispheric cerebral infarction and one patient with vascular headache. The slice level of dynamic CT was fixed at the atlas. The initial CT scan was taken after the start of infection of 20 or 40 ml of 60% meglumine amidotrizoate (this scan was used as a precontrast density reference), and 10 additional scans were made during 51.6 sec from the start of injection. The occluded internal carotid arteries were not visualized in patients with ICA occlusion, while all nonoccluded internal carotid arteries proven by angiography were enhanced clearly. It is concluded that this simple and noninvasive diagnostic examination should be added to the routine test procedures for evaluation and follow-up study of extracranial cerebral vascular disease.