The relationship between hypoperfusion distal to anterior circulation in symptomatic intracranial atherosclerosis and ischemic stroke recurrence:a quantitative study
Objective:This study aims to investigate the relationship between hypoperfusion distal to anterior circulation in symptomatic intracranial atherosclerotic disease(ICAD)patients and recurrent ischemic stroke. Methods:One hundred and thirty symptomatic patients caused by middle cerebral artery stenosis were retrospectively analyzed. They were divided into initial group,with the first episode of acute and subacute ischemic stroke/transient ischemic attack(TIA)(n=92);and recurrent group,with recurrent acute ischemic stroke/TIA(n=38). Hypoperfusion was assessed quantitatively based on time threshold of Tmax>4 s and Tmax>6 s. The degree of stenosis,border zone infarction(BZI)and hypoperfusion volume of Tmax>6 s and Tmax>4 s were measured and compared between groups using independent sample t test,non-parametric test,chi-square or fisher’s exact test as appropriate. Logistic regression model was constructed to investigate the risk factors for recurrent stroke. Receiver operating characteristic curve analysis was used to determine the diagnostic performance of the parameters. Results:Higher degree of stenosis(P=0.003),more BZI pattern(P=0.037)and higher hypoperfusion volume defined by both Tmax>4 s and Tmax>6 s(both P<0.001)were found in recurrent group compared to initial group. Multivariable logistic regression showed that hypoperfusion volume defined by Tmax>4 s was the only independent imaging marker that associated with stroke recurrence(OR=1.120,per 10 mL increase,95% CI:1.051~1.194,P < 0.001). The area under the ROC curve was 0.756(95%CI:0.672~0.839),with a sensitivity of 76.3% and a specificity of 63.0%. Conclusion:Higher volume of distal hypoperfusion defined by Tmax>4 s was independently associated with recurrent ischemic stroke,and thus may be a useful imaging marker for stratifying the risk of stroke recurrence in symptomatic ICAD patients.