Evaluation of the Vertebral Artery Anatomic Course with Multi-slice Spiral CT and Its Clinical Application

Objective To evaluate the value and the significance of 16-slice spiral computed tomography angiography(MSCTA) in identifying the vertebral artery course variation.Methods MSCTA data in 22 patients with anomalous path of vertebral artery were retrospectively analyzed,13 of them had undergone DSA examinations,and 5 of them had also undergone MRI examinations.Multi-planar reconstruction(MPR),curved MPR,thin-slab maximum intensity projection(MIP),volume rendering(VR) or slab VR(cut-plane VR) were used to assess the anomalous path of the vertebral artery and its relationship with the adjacent large vessels.Virtual endoscopy(VE) was used to evaluate the orifice of the vertebral arteries and its relationship with the aortic arch and the ostia of the adjacent large vessels.Different views of vertebral artery were analyzed on DSA.MSCTA and DSA images were analyzed in blinded fashion for the accuracy of anomalous vertebral artery path and origin detection.Results were compared in a secondary consensus evaluation.Results The anomalous path of the vertebral artery in all 22 patients were correctly displayed on MSCTA,7 of them had anomalous origin of vertebral artery,the anomalous of ostia showed clearly.The vertebral arteriae with course variation were all going up at the front of the foramen transversarium of C6,then bended into the C5,C4 or C3 foramen transversarium.DSA could only be detected the anomalous origin in 13 patients undergone DAS.5 patients indirectly showed having course variation of vertebral artery by MRI.Conclusion MSCTA is superior to DSA in showing the anomalous path and orifice of vertebral artery,it should be considered as a non-invasive imaging tool for these diseases.