Predictive value of susceptibility weighted imaging for ischemic penumbra in rats with ischemic stroke

Abstract

Objective To evaluate the predictive value of susceptibility weighted imaging (SWI) for ischemic penumbra in rats with ischemic stroke. Methods Thirty SD rats were used for modeling ofcerebral artery ischemia reperfusion via modified Longa method. After successful modeling, the rats underwentmagnetic resonanceexaminationfordiffusion-weighted imaging (DWI) , SWI, and perfusion-weighted imaging (PWI) sequences. The 2, 3 and 5-triphenyltetrazolium chloride (TTC) method was usedto detect the infarct size of brain tissues. The correlation between SWI and PWI was analyzed by Pearson correlation analysis. Kappa consistency test was performed to detect accuracy, sensitivity, specificity, positive predictive, negative predictive and Kappa values of SWI for detecting ischemic penumbra. The receiver operating characteristic (ROC) curve was generated to analyze predictive value of SWI for ischemic penumbra. The area under the curve (AUC) was calculated toevaluate the diagnosticaccuracy. Results The brain tissues ASPECTS scores of SWI and PWI were significantly positively correlated with DWI-unmatched areas (r=0.795, P=0.000. r=0.812, P=0.000) . Kappaconsistency analysis showed that the accuracy, sensitivity, specificity, positive predictive, negative predictive and Kappa values of SWI for diagnosis of ischemic penumbra were 92.00%, 100.00%, 93.33%, 100.00%, 71.43% and 0.793, respectively. ROC analysis showed that AUC of SWI for diagnosis of ischemia penumbra inischemic stroke rats was 0.933. Conclusion Relatively high predictive value ispossible with SWI for ischemic penumbra in ischemic stroke rats. Key words: Ischemic stroke; Susceptibility weighted imaging; Ischemic penumbra