Radiological Findings of Vertebral Artery Dissection

ABSTRACT

PURPOSE: The vertebral artery dissection is rare and increasingly recognized as a source of stroke. The purpose of this study is to describe causes, clinical manifestations, MRI and anglographic findings. MATERIALS AND METHODS: Conventional anglograms(n=7) and magnetic resonance imaging(n=6) were retrospectively analyzed in seven patients of vertebral artery dissection. The classification of the Krayenbuhl and Yasargil for vertebral artery segmentation was used for localization of vertebral artery dissection. Additionally, etiology and clinical manifestations were also retrospectively reviewed. RESULTS: Six cases were spontaneous type and one case was traumatic type. The clinical diagnoses of 6 spontaneous arterial dissection cases were wallenberg syndrome(4 cases), subarachnoid hemorrhage(1 case), and infarction of the cerebellum corresponding to PICA territory(1 case). A linear bright signal caused by thrombus was well visualized at the dissection area on sagittal T1 weighted spin echo MR images in all 6 cases. The characteristic anglographic findings were profound narrowing in 4 cases, pearl and string sign(including dissecting aneurysm) in 3 cases, complete obstruction in 3 cases, and a double density lumen(true and false lumen) extending to proximal basilar artery in one case. Spontaneous dissections were located at the V4 segment in all 6 cases. One traumatic dissection was located at the V2 segment. CONCLUSION: The most common site of the spontaneous dissection of the vertebral artery was V4 portion and a linear bright signal caused by thrombus was well visualized on sagittal T1 weighted spin echo MR images.