Internal carotid artery dissection: MR imaging features and clinical-radiologic correlation

PURPOSE: To analyze the usefulness of magnetic resonance (MR) imaging techniques and diagnostic sensitivity in internal carotid artery dissection (ICAD) and to correlate these findings with those of other imaging modalities and with clinical signs. MATERIALS AND METHODS: Thirty-one patients with ICAD underwent MR imaging within 2-40 days (mean, 13 days) after onset of clinical symptoms. All patients initially underwent Doppler sonography; 15 patients underwent additional angiographic studies. RESULTS: T1-weighted fat-suppressed MR images most accurately demonstrated intramural hematoma in the internal carotid artery (ICA) in all patients. Kinking or coiling of the ICA was found in nine (29%) patients. Hyperintense signal was seen on T1- and T2-weighted images in the carotid canal or in the cavernous sinus in two-thirds of the patients. Findings characteristic of ICAD were seen on 13 of 16 angiograms. CONCLUSION: MR imaging most accurately demonstrated ICAD. The high rate of kinking and coiling in the carotid artery suggests that these anatomic conditions may be predisposing factors.