Carotid and vertebral artery dissections: three-dimensional time-of-flight MR angiography and MR imaging versus conventional angiography.

PURPOSE: To compare three-dimensional time-of-flight magnetic resonance (MR) angiography, MR imaging, and transfemoral four-vessel angiography in diagnosis and follow-up of cervical artery dissection. MATERIALS AND METHODS: Eighteen patients with 19 extracranial internal carotid artery and five vertebral artery dissections were included in this prospective study. Blind interpretation of MR and angiographic images was made by two independent radiologists. RESULTS: MR angiography was more accurate than MR imaging in diagnosis of carotid dissection, although the difference was not statistically significant. In carotid artery dissection, respective sensitivity and specificity were 95% and 99% for MR angiography and 84% and 99% for MR imaging and in vertebral artery dissection were 20% and 100% for MR angiography and 60% and 98% for MR imaging. CONCLUSION: MR angiography is a reliable, noninvasive method for use in diagnosis and follow-up of extracranial internal carotid artery dissection. In vertebral artery dissection, however, conventional angiography remains useful.