Fluid-attenuated inversion recovery vascular hyperintensity: Correlation with other radiologic findings in acute ischemic stroke with middle cerebral artery occlusion

Objective: To assess fluid-attenuated inversion recovery (FLAIR) vascular hyper-intensity (FVH) and explore its relationship with CT perfusion (CTP) penumbral/infarct core mismatch ratio and diffusion weighted imaging (DWI) final infarct volume in acute ischemic stroke (AIS) patients with middle cerebral artery occlusion (MCAO). Methods: The CTP and MRI images of 38 AIS patients with MCAO were reviewed. The FVH score (longitudinal direction) [FVH score (L)] and FVH score (transverse direction) [FVH score (T)] were quantified on the FLAIR images. The FVH score (L) (range, 0-16) was based on a rostrocaudal extension of FVH and the FVH score (T) (range, 0-3) was based on FVH supply of the occluded MCA territory. The mismatch ratio was calculated from the ratio of the [mean transit time - cerebral blood volume (CBV)] lesion/CBV lesion on the CTP images. The DWI infarct volume was measured on the DWI images. Results: The mismatch ratio was larger for the group of FVH score (L)=7~8 than those of FVH score (L)=5~6 and FVH score (L)=3~4 (p=0.03), whereas the DWI infarct volume was smaller (p=0.04). Similarly, the mismatch ratio of FVH score (T)=2~3 group was larger than FVH score (T)=1 group (p=0.01), whereas the DWI infarct volume was smaller (p=0.02). Both FVH score (L) and FVH score (T) correlated positively with mismatch ratio (P=0.02, P=0.001, respectively), but negatively with DWI infarct volume (P=0.03, P=0.004, respectively). Conclusions: Higher FVH score is associated with larger mismatch ratio and smaller DWI infarct volume in AIS patients with MCAO. FLAIR vascular hyperintensity may represent collateral arterial circulation, and may play a role in protecting the ischemic penumbra.

Prognostic value of the ABCD2 score on long-term follow-up of transient ischemic attack using the new tissue-based definition

The ABCD2 score is validated for evaluating short-term stroke risk after transient ischemic attack (TIA); however, whether it is able to predict the long-term risk of vascular outcome remains uncertain. Recently a new tissue-based definition of TIA has been proposed. The ABCD2 scores of 145 TIA patients admitted to our hospital were retrospectively calculated and stratified into two categories: ≤ 3 points (low risk); 4-7 points (moderate-high risk). At a median follow-up of 81 months, new vascular events were recorded. Follow-up data were available in 107 patients. Seventy one patients had a moderate-high ABCD2 score. Sixty six patients experienced a cerebral ischemic event; 8 a myocardial infarction; 7 died of cerebrovascular or cardiovascular cause. Moderate-high ABCD2 score was significantly associated with the further cerebral ischemic events (hazard ratio [HR], 1.755; 95% confidence interval [CI], 1.019 to 3.024) and with the combined endpoint (HR, 1.818; 95% CI, 1.079 to 3.063). Our study shows that the ABCD2 score may also be used to predict long-term vascular outcome after tissue-based definition of TIA. Moderate-high ABCD2 score is associated with an increased general vascular risk in the long-term follow-up after TIA.