The Association of Vertebrobasilar System Morphology and Geometry with the Posterior and Anterior Ischemic Stroke

Objective: Morphometric and geometric variations in the vertebrobasilar system (VBS) may influence cerebral hemodynamics, potentially contributing to ischemic strokes in both anterior and posterior circulatory territories. This study aimed to investigate the association between VBS morphology and ischemic stroke localization. Methods: This retrospective observational study analyzed multidetector computed tomography angiography images from 431 patients (187 females, 244 males, mean age: 65.3 ± 14.6 years). Patients were categorized into three groups: anterior circulation ischemic stroke (ACIS, n=184), posterior circulation ischemic stroke (PCIS, n=88), and control subjects (n=159). Morphometric parameters were assessed using 3D Slicer software. Results: Significant differences in basilar artery (BA) length were observed between stroke groups and controls, with ACIS and PCIS groups exhibiting longer BA lengths (p<0.05). Males had significantly longer vertebral artery (VA) lengths than females in the control and ACIS groups (p value < 0.05). The vertebrobasilar junction angle was significantly wider in females than in males (p value = 0.046). BA bending was predominantly directed to the right across all groups, with no significant differences between the stroke and control groups. VA dominance was more frequent on the left in ACIS and the right in PCIS, while VA hypoplasia was less common in stroke patients compared to controls, contrary to previous reports. Conclusion: While certain morphometric and geometric variations in the VBS were observed, the evidence for a direct association between these characteristics and the localization of ischemic stroke was limited and inconclusive. These findings suggest that vertebrobasilar morphology may not independently determine stroke localization.