Detection of intracranial aneurysm with time-of-flight MRA at 3.0Tesla: comparison with digital subtraction angiography

Objective: To evaluate the diagnostic accuracy of time-of-flight (TOF)MRA with 3.0 Tesla scanner for intracranial aneurysms. Methods: Thirty four patients clinically suspected intracranial aneurysm underwent both 3.0T TOF MRA and intra-arterial digital subtract angiography (DSA)examination. All image data were prospectively interpreted by three experienced neuroradiologists on post-processed workstation. Two of them retrospectively read the MIP images alone, as group I; one of them read both the MIP and source images, as group II. Considering the results of DSA as the standard reference, we evaluated the sensitivity, specificity, and accuracy of 3.0T TOF MRA for imaging the intracranial aneurysms. Results: Twenty aneurysms (19 cases) were detected on DSA examinations, including internal carotid artery (7), anterior communicating artery (5), posterior communicating artery (5), anterior cerebral artery (1) and middle cerebral arter (1). The overall sensitivity, specificity and accuracy of MRA were 94.8%, 89.4%, and 91.4% respectively. The diagnostic performance efficacy in group II was higher than group I, but no statistically significant difference between group I and group II was found on the diagnostic accuracy of 3.0T TOF MRA. Conclusion: 3.0T TOF MRA is a rapid, non-invasive diagnostic imaging method and can clearly display the contour of the intracranial aneurysms. MIP combined with Source images could improve the diagnostic accuracy of 3.0T TOF MRA for detection of intracranial aneurysms. (authors)