Jiang XY, Zhang SH, Xie QZ, et al. Evaluation of Virtual Noncontrast Images Obtained from Dual-Energy CTA for Diagnosing Subarachnoid Hemorrhage. http://www.ajnr.org/content/36/5/855.full A group of 37 patients underwent noncontrast CT and dual-energy CTA for diagnosis of SAH. From the latter, virtual