双源CT低管电压结合低浓度对比剂在肝脏增强扫描中的应用  

Application of dual-source CT low tube voltage combined with low concentration contrast agent in enhanced imaging of the liver

作　　者：吕仁锋[1] 袁丽萍[1] 李超[1] 谭晓天[1] 

机构地区：[1]大连医科大学附属中心医院放射线科,辽宁116000

出　　处：《放射学实践》2015年第10期994-996,共3页Radiologic Practice

摘　　要：目的:探讨双源CT使用低管电压(100kVp)和低浓度等渗对比剂(270mg I/mL)进行肝脏增强扫描的可行性。方法:将我院108例行肝脏CT增强扫描的患者随机分成两组,每组54例。A组:管电压100kVp,对比剂为威视派克(270mg I/mL)。B组:管电压120kVp,对比剂为碘克沙醇(320mg I/mL)。测量、计算两组图像的对比噪声比(CNR)、信噪比(SNR)、肝实质CT值、肝动脉CT值、门静脉CT值及有效辐射剂量(ED),并对两组图像进行主观评分,对两组间上述指标进行统计学分析。结果:A组的CNR高于B组,且差异具有统计学意义(t=2.88,P<0.05),SNR高于B组(P<0.05),A组能够提供清晰的诊断图像,提高病变的显示;A、B组的图像质量评分差异无统计学意义(t=-0.58,P>0.05);A、B组的肝实质CT值及肝动脉CT值均无统计学差异(t=-1.81,P>0.05;t=0.96,P>0.05),而A组的门静脉CT值高于B组(t=7.55,P<0.05);A组的三期总辐射剂量[(8.04±1.12)mSv]低于B组[(11.62±2.41)mSv](t=9.94,P<0.001)。结论:双源CT肝脏增强扫描采用管电压100kVp和低浓度等渗对比剂(270mg I/mL)可以提供较好的图像CNR,提高门静脉CT值,保证诊断图像质量的同时降低辐射剂量。Objective：To explore the feasibility of dual-source CT using low tube voltage 100 kVp and low concentration 270 mg I/mL isotonic contrast medium in enhanced imaging of the liver.Methods：108patients having undergone CT enhanced imaging were randomly divided into two groups：54in each group.Group A：tube voltage was 100 kVp,and contrast agent being visipaque（270mg I/mL）.Group B：tube voltage was 120 kVp,and contrast agent being iodixanol（320mg I/mL）.Image contrast-to-noise ratio（CNR）,image signal-to-noise ratio（SNR）,hepatic parenchyma CT value,hepatic artery CT value,and portal vein CT value were recorded and calculated.All the images of the two groups were given subjective ratings and statistical analyses were made for all data of the groups.Results：The image contrast-to-noise ratio and signal-to-noise ratio of group A were higher than that of group B,the difference was statistically significant（P〈0.05）,thus improving the display of the pathological changes.Scores for image noise and image quqlity were similar between the two groups,having no statistical significance（P〉0.05）.Liver parenchyma and hepatic artery CT values of the two groups had no statistical difference（P〉0.05）.Portal vein CT value of group A was higher than that of group B（P〈0.05）.The total radiation dose of three phases in groups A [（8.04±1.12）mSv]was lower than that in group B [（11.62±2.41）mSv,P〈0.001],being reduced by about 30%.Conclusion：Dual-source CT enhancement imaging of the liver using tube voltage100 kVp and isotonic contrast medium in low concentration 270 mg I/mL can provide better image contrast to noise ratio,increase the portal vein CT value,and reduce significantly the radiation dose on the basis of ensuring the quality of diagnostic images.

关 键 词：肝脏 辐射剂量 对比剂 体层摄影术 X线计算机 

分 类 号：R575[医药卫生—消化系统] R816.5[医药卫生—内科学]