Angiographic characteristics of ruptured versus unruptured vertebral artery dissecting aneurysm

OBJECTIVE: Vertebral artery dissecting aneurysm (VADA) is a rare and critical disease. VADA rupture can cause subarachnoid hemorrhage which is a major complication of VADA due to their high rebleeding rate and poor outcome. In the present study, ruptured and unruptured VADAs were compared by analyzing angiographic findings to determine useful predisposing factors for VADA rupture for appropriate treatment selection. METHODS: Subjects with VADA treated during a 10-year period were retrospectively identified. The 57 cases diagnosed with VADA were divided into ruptured (n=15) and unruptured (n=42) groups. In addition, each case was analyzed using angiographic 3-dimensional (3-D) reconstructed images. Factors such as length, dilated and stenotic diameter, shape, and vessel around the vertebral artery (VA) were measured and statistically compared. RESULTS: In the ruptured group, stenotic findings of the affected lesion were more common and severe than in the unruptured group. The average stenotic diameter was 2.27 mm (vs. 2.84 mm). And stenotic degree was 62% and 53% in the ruptured and unruptured groups, respectively. Posterior communicating artery (PcomA) flow was more common in the ruptured group (87% vs. 55%, p=0.028). CONCLUSIONS: Based on angiographic findings, stenotic lesions, which may be influenced by PcomA flow, are more common in ruptured VADAs.