Vertebrobasilar Artery Dissection Research Articles

出血型椎骨脳底動脈系解離性動脈瘤

Fifteen patients of ruptured intracranial vertebrobasilar artery dissection (VBDA) were studied to clarify the clinical problems during treatment. Subsequent rebleeding occurred in 5 of the 15 cases (33.3%) and the mortality rate of patients with rebleeding was 40%. All subsequent rebleeding cases were VBDA of the distal to PICA type. These patients were divided into two groups consisting of a surgical treatment group (chronic stage) with 9 cases and a nonsurgical treatment group with 6 cases. Surgical procedures included proximal occlusion (PO) of the vertebral artery in 7 patients, wrapping in 1 and direct clipping in 1. Postoperative complications occurred in 3 patients by PO. Although proximal occlusion seemed to be a simple and useful method to prevent rebleeding, the occurrence of ischemic complication remains to be solved. Further study is needed to determine the best treatments, including PO for VBDA.

Magnetic resonance imaging study of intracranial vertebrobasilar artery dissections.

The purpose of this study is to demonstrate the magnetic resonance features of intracranial vertebrobasilar artery dissections and to determine the potential and limitations of magnetic resonance imaging in their diagnosis. We studied five consecutive patients with angiographically verified intracranial vertebrobasilar artery dissection with magnetic resonance imaging (0.5 T) in regard to the shapes of the intramural hematoma and the chronological change of its signal intensity. We also estimated the sensitivity of magnetic resonance imaging for diagnosing dissection. We observed intramural hematoma in four patients on the first magnetic resonance scan and in all five patients during the course of the study. The shapes of the intramural hematomas were curvilinear, crescentic, "bamboo-cut," "band-like," and spotty. The intensity of the intramural hematoma varied according to its age. On the T1-weighted and the proton images, the intramural hematomas appeared isointense to slightly hyperintense in the first few days and became hyperintense thereafter. The intramural hematomas became isointense or unrecognizable 2 months after onset. The T1-weighted image and the proton images were superior to the T2-weighted image in demonstrating the intramural hematomas. Magnetic resonance imaging is a sensitive tool for diagnosing intracranial vertebrobasilar artery dissection, particularly in the subacute to early chronic stage. Magnetic resonance imaging is complementary to angiography in that it can directly visualize intramural hematomas.