Clinical evaluation of fluid attenuated inversion recovery vascular hyperintensity in acute anterior circulation infarction

Abstract

Listen

Translate article

Objective To evaluate whether MRI fluid attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is an effective indicator for severe vascular stenosis or occlusion and disease severities in patients with acute anterior circulation infarction. Methods Three hundred and forty consecutive patients with acute anterior circulation infarction, admitted to our hospital from May 2013 to May 2014, were enrolled as subjects. All subjects were completed brain MR diffusion-weighted imaging (DWI), FLAIR and neck vascular or brain magnetic resonance angiography (MRA). According to the extent of FVH, all subjects were classified into negative FVH and positive FVH groups. Clinical data were obtained and compared among patients with different grades of FVH, and receiver operating characteristic (ROC) curve was used to calculate the sensitivity and specificity of FVH diagnosis of vascular severe stenosis or occlusion. The value of FVH in evaluating the disease severities of patients with large artery atherosclerosis combined with acute cerebral infarction according to new TOAST classification was evaluated. Results FVH was observed in 109 (32.06%) of the 340 patients. Significant differences were noted in the new TOAST classification ratio and vascular stenosis grading between the two groups; in the positive FVH group, the largest ratio was patients with large-artery atherosclerosis (82.6%), while that was patients with small vessel diseases (56.3%); the ratio of patients with severe vascular stenosis and occlusion in positive FVH patients was significantly higher than that in negative FVH patients (34.9% vs. 5.6%, 39.5% vs. 0.9%). Spearman rank correlation analysis indicated that the degrees of vascular stenosis of carotid artery-middle cerebral artery were positively correlated to FVH (r=0.599, P=0.000). As compared with the negative FVH group, FVH patients had larger infarct volume and higher initial NIHSS scores (P<0.05). ROC curve indicated that FVH had a sensitivity of 84.38% and a specificity of 88.52% in detecting artery stenosis (area under the curve [AUC]=0.892, 95% CI=0.85-0.94, P<0.05), and a sensitivity of 88.89% and a specificity of 85.76% in detecting the vessel occlusion (AUC=0.929, 95%CI: 0.89-0.97, P<0.05). In patients with acute cerebral infarction combined with artery atherosclerosis, patients with high FVH scores showed smaller infarct volumes and slighter neurological symptoms as compared with those with low FVH (P<0.05). Conclusions FVH predicts vascular severe stenosis or occlusion with high sensitivity and specificity. In severe vascular stenosis or occlusion group, higher FVH scores are associated with lighter strokes. Key words: Magnetic resonance imaging; Fluid attenuated inversion recovery; Vascular hyperintensity; Acute cerebral infarction; Atherosclerosis