Dual-Energy CT Composite Images Aiming at Visualization of Acute Cerebral Stroke in Emergency : A Phantom Study

This study proposed to visualize acute cerebral stroke using dual-energy CT, when judging whether thrombolytic therapy with use of recombinant tissue plasminogen activator (rt-PA) was applicable. Dual-energy images were obtained using different energy levels, and the possibility of visualizing acute cerebral stroke using the obtained images was investigated. Using a previously developed cerebral stroke phantom, and images were obtained with tube voltages combination at 80kV: Sn140kV, 100kV:Sn140kV, 140kV:80kV. Subsequently, composition images with different tube voltage patterns were obtained in such a way that the sum of the assigned weight coefficients became 1.0. By calculating CNR values, the ability to visualize the disease was evaluated. When the weight coefficients at the low and high energy sides were 0.5-0.6 and 0.4-0.5, respectively, the composition images possessed the highest CNR value. Therefore, this study demonstrated the possibility that dual-energy CT images were useful for visualizing acute cerebral stroke.