EVALUATION OF EXTRACRANIAL VERTEBRAL ARTERY DISSECTION WITH DUPLEX COLOR-FLOW IMAGING

Background and Purpose We describe the diagnostic potential of duplex color-flow imaging in the evaluation of extracranial vertebral artery dissection. Methods Twenty patients with 24 extracranial vertebral art ery dissections (four bilateral) were examined with duplex ultrasonogr aphy over a period of 6 years. Color-flow imaging was carried out in 1 6 of these patients. In 15 patients (75%), the dissection was temporal ly related to trauma. Angiography was available in 18 patients, confir ming the diagnosis. Results In 15 patients, the diagnosis was primaril y established with ultrasonography. Five patients with a dissection we re referred for follow-up color-flow examinations. Six vertebral arter ies were dissected at the origin or in the proximal V1 segment, one in the distal V2 segment, and one at the atlas loop. In contrast to othe r studies, the most frequent localization of the dissection in our pat ients was the region between the V1 and V2- segments (n=16), where the most typical dissection site was the entrance of the artery into the transverse foramen of the C6 vertebra (n=11). Typical ultrasonographic findings were irregular stenosis, dissecting membrane with true and f alse lumen, localized increase in diameter of the artery, pseudoaneury sm, intramural hematoma, and tapering stenosis with distal occlusion. In follow-up examination, a good regression of pathological findings w as found in 17 dissections (70.8%). Two occlusions were completely rec analized. Conclusions Extracranial vertebral artery dissections can be diagnosed noninvasively with duplex color-flow imaging. It is therefo re a useful method for early diagnosis and follow-up examination.