Fellows’ Journal Club
August 2014
(3 of 3)
Because FLAIR high signal intensity in occluded arteries occurs elsewhere in the brain, these authors analyzed the signal of the basilar artery in 20 instances of occlusion in a group of patients who also underwent DSA. While the FLAIR hyperintense basilar artery sign showed moderate sensitivity, its specificity and accuracy were high for the detection of occlusions. The extent of the occlusion also predicted survival.
Abstract
BACKGROUND AND PURPOSE
FLAIR-hyperintense vessels are known to be a sign of sluggish collateral blood flow in hemispheric vessel occlusion. Additionally, they seem to have a prognostic implication. The aim of the current study was to evaluate the hyperintense configuration of the basilar artery (FLAIR-hyperintense basilar artery) as a marker of basilar artery occlusion and as a predictor of patient outcome.
MATERIALS AND METHODS
We retrospectively identified 20 patients with basilar artery occlusion who initially underwent MR imaging with subsequent DSA. The diagnostic accuracy of the FLAIR-hyperintense basilar artery sign was tested by 4 independent readers in a case-control design, and the relation among FLAIR-hyperintense basilar artery and DWI posterior circulation–ASPECTS, patient outcome, and patient survival was evaluated. To grade the extent of the FLAIR-hyperintense basilar artery sign, we generated a score by counting the number of sections from the basilar tip to the foramen magnum in which a hyperintense signal in the vessel lumen was present multiplied by the section thickness.
RESULTS
The FLAIR-hyperintense basilar artery sign showed moderate sensitivity (65%–95%) but very good specificity (95%–100%) and accuracy (85%–93%) for the detection of basilar artery occlusion. Substantial or excellent inter-reader agreement was observed (Cohen κ, 0.64–0.85). The FLAIR-hyperintense basilar artery inversely correlated with the posterior circulation–ASPECTS (r = −0.67, P = .01). Higher FLAIR-hyperintense basilar artery scores were associated with patient death (28.3 ± 13.7 versus 13.4 ± 11.1, P < .05).
CONCLUSIONS
The FLAIR-hyperintense basilar artery sign proved to be a valuable marker of vessel occlusion and may substantially support the diagnosis of basilar artery occlusion. The established FLAIR-hyperintense basilar artery score may be helpful for the prediction of individual patient survival.
