Conventional T2-Weighted Imaging to Detect High-Grade Stenosis and Occlusion of Internal Carotid Artery, Vertebral Artery, and Basilar Artery.

BACKGROUND: To evaluate the reliability of conventional T2-weighted imaging (WI) for detecting high-grade stenosis and occlusion of cerebral arteries by disappearance of artery flow void signals.

METHODS: Our hospital's neuroimaging data on patients with ischemic stroke or transient ischemic attack were collected, including only those from patients who underwent both conventional brain T2WI and three-dimensional time-of flight magnetic resonance angiography (3D-TOF MRA). Flow void signals of conventional axial T2WI were analyzed by 2 young neurologists and compared with 3D-TOF MRA as the gold standard to determine the specificity for detection of high-grade stenosis and occlusion of cerebral arteries. Interobserver agreement was evaluated by calculating kappa (κ) coefficients.

RESULTS: Of the 1765 patients included, disappearance of flow void signals was detected in 445 major cerebral arteries in 320 patients on conventional axial T2WI. The specificity of disappearance of flow void signal for the diagnosis of high-grade stenosis and occlusion was 94% for internal carotid arteries, 96.2% for vertebral arteries, and 92% for basilar arteries. K coefficients were greater than .94 for all arteries.

CONCLUSIONS: Disappearance of flow void signal on conventional axial T2WI is a reliable indicator of high-grade stenosis or occlusion of major cerebral arteries. Conventional axial T2WI is a useful tool in the diagnosis of cerebral artery steno-occlusive disease.