Blinded prospective evaluation of sensitivity of MR angiography to known intracranial aneurysms: importance of aneurysm size.

Abstract

Three-dimensional time-of-flight MR with 512 x 256 matrix is more sensitive than three-dimensional phase-contrast or standard MR imaging for detection of aneurysms. Retrospectively, aneurysms 3 mm or larger can be identified with MR angiography; however, prospectively, 5 mm is the critical size for detection.