PURPOSE: To analyze the usefulness of magnetic resonance (MR) imaging
techniques and diagnostic sensitivity in internal carotid artery disse
ction (ICAD) and to correlate these findings with those of other imagi
ng modalities and with clinical signs. MATERIALS AND METHODS: Thirty-o
ne patients with ICAD underwent MR imaging within 2-40 days (mean, 13
days) after onset of clinical symptoms. All patients initially underwe
nt Doppler sonography; 15 patients underwent additional angiographic s
tudies. 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 pa
tients. Findings characteristic of ICAD were seen on 13 of 16 angiogra
ms. 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.