Diagnosis of Vertebral Artery Fenestration by 64 Slices Spiral CT Angiography

Objective To analyze the CT angiographic features of basilar artery fenestrations in an effort to improve recognition of this anomaly. Materials and Methods The imaging data of 37 patients with basilar artery fenestrations were evaluated retrospectively. The fenestration's incidence,location,configuration and relationship between the anomaly and surrounding structures were analyzed. The coexisting abnormalities were also evaluated. Results Among the 2051 patients'head and carotid CTA images,37 fenestrations of vertebral artery(1.8%) were found,which 19 fenestrations were at the intracranial level,16 fenestrations were at extracranial level,and 2 fenestrations located at atlantoaxial level and the intracranial segment of the artery. 2 small fenestrations (less than 2 mm) presented foramen-like.15 of 35 larger fenestrations simulated an ok hand sign,and 20 fenestrations showed partial duplication type of fenestration.1 case coexisted with aneurysm of other artery. 2 patients were associated with anterior cerebral artery fenestrations. Conclusion 64-slices CTA is a rapid,intuitive,and accurate method for demonstrating vertebral artery fenestration and its coexisting abnormalities,and may be helpful for procedures choice and decreasing the risk of operation.