Dual-Energy CT Composition Images for Visualization of Acute Cerebral Stroke in Emergency
Traditionally,it has been difficult to visualize acute cerebral infarction from images produced by X-ray computed tomography (CT).This study proposed to visualize acute cerebral infarction 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 infarction using the obtained images was investigated.Using a previously developed cerebral apoplexy phantom,an imitation disease with 32 HU and 34HU was set to be visualized,and images were obtained with tube voltages at 80,100,140,and Sn140 kV,and combination at 80kV:Sn140kV,100kV:Sn140kV,140kV:80kV.A weight coefficient between 0.1-0.9 was assigned to each image.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 contrast-to-noise ratio (CNR) values,the ability to visualize the disease was evaluated.When the weight coefficients at the low and high energy sides were 0.4-0.5 and 0.5-0.6,respectively,the composition images possessed the highest CNR value.In each pattern,the composition image had higher CNR values than the original image.Based on the results obtained in previous studies,the minimum conditions to obtain images with CNR values exceeding 1.0 were as follows: tube voltage,120 kV; mAs,400 mAs; and dose,21.0 mGy.Although a composition image required two images,the sum of the doses was 19.3 mGy.Because of the reduction by approximately 2.0 mGy.Therefore,this study demonstrated the possibility that dualenergy CT images were useful for visualizing acute cerebral infarction.
Dual-Energy CT Acute cerebral Stroke Composition image Emergency
H. Hara H. Muraishi T. Inoue S. Abe H. Satoh Y. Nakajima
School of Allied Health Sciences, Kitasato University, Sagamihara, Japan;Department of Radiology, St School of Allied Health Sciences, Kitasato University, Sagamihara, Japan Department of Radiology, St. Marianna University School of Medicine, Kawasaki, Japan School of Health Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki, Japan
国际会议
World Congress on Medical Physics and Biomedical Engineering (2012年医学物理及生物医学工程国际会议(IFMBE))
北京
英文
831-834
2012-05-26（万方平台首次上网日期，不代表论文的发表时间）