Diagnostic ability of 3-dimensional contrast-enhanced MR angiography in identifying vertebral basilar artery stenosis

Vertebral-basilar artery stenosis is associated with posterior circulation infarction. So correct detection of vertebral basilar artery stenosis is very important. Studies concerning the sensitivity and specificity of 3-dimensional contrast enhanced MR angiography (3D-CE-MRA) in detecting vertebral basilar artery stenosis is generally lacking.

Retrospectively reviewed the imagines of consecutive one hundred and forty-nine Chinese patients with ischemic stroke or vertigo/dizziness who underwent 3D-CE-MRA and DSA. DSA and CE-MRA images were studied separately and to determine the presence of mild, moderate, or severe stenosis of the vertebral-basilar arteries. Analysis combined with vascular origin image was applied when evaluating the vertebral artery origin stenosis. Sensitivity, specificity, positive and negative predictive values, and the accuracy of 3D-CE-MRA in detecting and grading of vertebral-basilar artery stenosis were calculated.

Compared with DSA, sensitivity, specificity and accuracy of 3D-CE-MRA in detecting of vertebral artery origin ≥70% stenosis or occlusion was 97.1%, 77.4% and 81.9%, but diagnostic consistency was poor (K=0.59); Analysis combined with vascular origin images, the specificity (97.8%), accuracy (92.9%) and consistency (K=0.826) was significantly improved.

3D-CE-MRA is a sensitive and noninvasive technique for the detection of vertebral artery origin stenosis. Furthermore, analysis combined with vascular origin image would improve the diagnostic accuracy.