Value of dual-source dual-energy CT in differentiating extravasation of iodine contrast agents from secondary hemorrhage after revascularization in acute ischemic stroke / 实用医学杂志

ABSTRACT

Objective To explore the value of dual-source dual-energy CT (DSDE-CT) in differentiating extravasation of iodine contrast agents from secondary hemorrhage after revascularization in acute ischemic stroke. Methods 46 acute ischemic stroke patients following intra-arterial thrombolysis were examined with DSDE-CT within 2 hours after the procedure. Simultaneous imaging at 80 kV/392 mA and 140 kV/196 mA was employed, and then mixed images, virtual unenhanced non-contrast images and iodine overlay maps were calculated. Mixed images alone, as conventional CT, and DUDE-CT interpretations were assessed separately by two radiologists and compared with follow-up CT. Results 6 of 34 patients were negative cases proven by CT without high density, and another 28 cases were proven positive cases with 3 cases of cerebral hemorrhage, 21 cases of contrast agent extravasation, and the remaining 4 cases of combined cerebral hemorrhage and contrast agent extravasation. The sensibility, specificity, positive predictive value, negative predictive value and accuracy of mixed imaging alone in diagnosing hemorrhage was 66.67%, 100%, 1005, 96.15% and 96.43%, while the sensibility, specificity, positive predictive value, negative predictive value and accuracy of hemorrhage with DUDE-CT was 100%, 96%, 75%, 100% and 96.43% . The diagnostic accuracy of superimposed fusion images for intracranial hemorrhage, extravasation of contrast agent and hemorrhage with extravasation of contrast agent was relatively high, and the difference was statistically significant (P < 0.05). The diagnostic accuracy of superimposed fusion images consistent with clinical follow-up was significantly higher (Kappa=0.815),as compared with that of mixed imaging alone (Kappa=0.0.564). Conclusion DUDE-CT has great value in differentiating hemorrhage from iodinated contrast after intra-arterial thrombolysis in acute ischemic stroke.