Value of dual-source 64-slice CT angiography in the diagnosis of vertebral artery stenosis

Objective To investigate the accuracy of dual source 64-slice CT angiography (CTA) in the diagnosis of vertebral artery stenosis. Methods Fifty-eight patients (116 vertebral arteries) with posterior circulation cerebral ischemia received CTA and digital substraction angiography (DSA) simultaneously. The classification of stenosis degree was performed by using the experimental method of the North American symptomatic carotid endarterectomy. DSA was used as a standard, the accuracy of CTA in the diagnosis of vertebral artery stenosis was evaluated. Results The results of 96 in the 116(82.8%) vertebral arteries detected with CTA were corresponded with the results of vertebral artery stenosis rate diagnosed by DSA; the degree of stenosis in 17 vertebral arteries (14.6%) was slightly higher, and in 3 (2.6%) was slightly lower. When vertebral artery stenosis rate diagnosed by CTA was ≥70%, the sensitivity, specificity, negative predictive value, positive predicting value, and diagnose accordance rate were 96.3%, 96.6%, 89.7%, 98.9%, and 96.6%, respectively. The results of stenosis rate diagnosed by CTA were positively correlated with those of DSA (r=0.982,P0.01). The DSA regression equation calculated by DSA is Y (DSA)=0.936X (CTA) -1.108. Conclusion CTA has very high correlation with DSA in diagnosing the stenosis degree of vertebral artery, and the former can be used as a routine examination in screening of vertebral artery stenosis.