摘要
目的使用第二代Siemens双源CT对食管癌患者行双能双期增强扫描,获得食管癌病变、正常食管壁及图像噪声的能谱曲线,经计算获得病变的CNR、SNR曲线,寻找显示食管癌病变的最佳单能量(keV),并评价双期最佳单能量图像对食管癌病变的显示能力。方法使用第二代Siemens双源CT对37例食管癌患者行双能双期增强扫描,A球管管电压80 kVp,B球管管电压140 kVp,采用CARE DOSE 4D技术,经肘静脉注射对比剂70 ml后分别于第25 s(动脉期)及60 s(静脉期)行双能量扫描。应用"Monoenergetic"软件,使用1 mm层厚图像获得食管癌病变、正常食管壁及图像噪声的能谱曲线。经计算获得病变的CNR、SNR曲线,找到显示食管癌病变的最佳单能量(keV)。对照组为融合图像以及最佳单能量相邻的两个单能量图像。结果 (1)食管癌病变、正常食管壁的能谱曲线自低能量至高能量逐渐递减,食管癌病变的能谱曲线高于正常食管壁的能谱曲线。(2)动脉期、静脉期显示病变的最佳单能量(keV)均出现在70 keV,病变的CNR、SNR曲线的最大值均出现在70 keV;图像噪声最小值均出现在70 keV。(3)70 keV条件下动脉期病变的CNR大于静脉期,而静脉期病变的SNR大于动脉期。结论显示食管癌病变的最佳单能量出现在70 keV,动脉期对于病变的显示具有较大的优势,而静脉期对于显示食管癌病变内部结构及与周围组织关系具有较大优势。
Objective Using the second generation Siemens dual-source CT scanner to perform dual-energy bi-phase CT scanning for patients with esophageal cancer in order to obtain the spectrum curves of the lesions,the normal esophageal wall and the image noise.CNR and SNR were calculated,and the optimal monochromatic energy（keV） for esophageal cancer was determined.The demonstration ability of bi-phase optimal monochromatic energy image for esophageal cancer was evaluated.Methods By using the second generation Siemens dual-source CT scanner the dual-energy bi-phase contrast-enhanced CT scanning was performed in 37 patients with esophageal cancer.＂A＂tube voltage was set at 80 KVp,and＂B＂tube voltage was set at 140 KVp,using CARE DOSE 4D technique.The contrast medium of 70 ml was injected through elbow vein,which was followed by dual-energy scanning,including arterial phase（starting at 25 second） and venous phase（starting at 60 second）.The slice thickness of 1mm was used for CT scanning,and using ＂ Monoenergetic＂ software the spectrum curves of the lesions,the normal esophageal wall and the image noise were determined.The lesion＇s CNR and SNR curves were obtained through calculation,and optimal monochromatic energy（keV） for the visualization of esophageal cancer was determined.Results（1） The spectrum curves of the cancer and normal wall decreased as the keV increased,and the spectrum curve of the cancer was higher than that of the normal wall.（2） The optimal monochromatic energy was 70 keV in both arterial and venous phases.The maximum value of CNR and SNR of the cancer appeared at 70 keV,while the minimum value of the image noise was observed at 70 keV.（3） At 70 keV,the lesion＇s CNR value in arterial phase was higher than that in venous phase,while the lesion＇s SNR value in venous phase was higher than that in arterial phase.Conclusion The optimal monochromatic energy for the visualization of esophageal cancer is 70 keV,the arterial phase image is superior to the venous phase imag
出处
《临床放射学杂志》
CSCD
北大核心
2014年第10期1588-1592,共5页
Journal of Clinical Radiology
关键词
双源CT
双期增强
最佳单能量图像
食管癌
Dual-energy CT Bi-phase enhancement Optimal monochromatic energy image Esophageal cancer
