TY - JOUR T1 - Significance of Development and Reversion of Collaterals on MRI in Early Neurologic Improvement and Long-Term Functional Outcome after Intravenous Thrombolysis for Ischemic Stroke JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 1839 LP - 1845 DO - 10.3174/ajnr.A4384 VL - 36 IS - 10 AU - M. Ichijo AU - E. Iwasawa AU - Y. Numasawa AU - K. Miki AU - S. Ishibashi AU - M. Tomita AU - H. Tomimitsu AU - T. Kamata AU - H. Fujigasaki AU - S. Shintani AU - H. Mizusawa Y1 - 2015/10/01 UR - http://www.ajnr.org/content/36/10/1839.abstract N2 - BACKGROUND AND PURPOSE: Predicting response to rtPA is essential in the era of endovascular therapy for stroke. The purpose of this study was to elucidate prognostic factors of early neurologic improvement and long-term outcome with respect to the development and reversion of leptomeningeal collaterals in recanalization therapy after acute ischemic stroke.MATERIALS AND METHODS: We analyzed consecutive patients with proximal MCA occlusion treated with rtPA from 2007 to 2012 at 2 hospital stroke centers. All patients routinely underwent brain MR imaging before rtPA. To assess the reversion of collateral signs, we included patients who underwent follow-up MR imaging. We assessed the development and reversion of collaterals by using a combination of 2 MR imaging collateral markers, the hyperintense vessel sign and the posterior cerebral artery laterality sign. Early neurologic improvement was defined as a decrease in the NIHSS score of ≥10 or a score of ≤2 at 24 hours of treatment.RESULTS: Early neurologic improvement was observed in 22 of 48 eligible patients. The development of collaterals at arrival (15/22 versus 9/26, P = .042) was significantly associated with early neurologic improvement. Multivariate analysis adjusting for other variables showed that the development of collaterals at arrival (OR, 4.82; 95% CI, 1.34–19.98; P = .015) was independently associated with early neurologic improvement. Reversion of collaterals was significantly associated with successful recanalization (P < .001), and multivariate analysis showed that the reversion of collaterals was an independent prognostic factor of long-term functional outcome (OR, 5.07; 95% CI, 1.38–22.09; P = .013).CONCLUSIONS: Our results indicate that the development of leptomeningeal collaterals plays a crucial role in achieving early neurologic improvement, and reversion of collaterals predicts a favorable outcome via arterial recanalization after rtPA treatment for acute stroke.ENIearly neurologic improvementHVhyperintense vesselIQRinterquartile rangeMCAmiddle cerebral arteryPCAposterior cerebral arteryTIMIThrombolysis in Myocardial Infarction ER -