多层螺旋CT双通路注射法行肝门静脉系统成像的研究

目的:确定多层螺旋CT肝门静脉系统检查的合理延迟时间及双通路注射对比剂法的可行性。方法:分为2个步骤研究:①随机选择无腹部及心血管疾患的患者53例,以3 ml/s速率注射造影剂20 ml,行同层动态扫描,计算腹主动脉、肝门静脉、下腔静脉、肝实质的对比剂时间密度曲线,及它们的相关性。②47例需门静脉检查的患者,行MDCT肝区移床式、动态扫描,在右肘部静脉及下肢静脉同时注入对比剂,对比剂总量1.5~2 ml/kg。扫描时使用对比剂自动示踪软件,设动脉血管阈值为120 HU启动扫描,动脉期扫描完成后延时20.1±5.54 s行门静脉扫描,分别评价肝门静脉、肝静脉、下腔静脉的显示率及程度。结果:①20 ml对比剂注射同层动态扫描肝门层面腹主动脉达峰时间为18.5±4.81 s,肝门静脉达峰时间是38.61±6.59 s,下腔静脉达峰时间是55.44±12.16 s,肝实质的达峰时间是56±5.7 s。②肝门静脉显示率达100%,肝门静脉主干等显示程度平均评分2.50~2.93;相关小分支静脉显示率为87%~98%,显示平均评分2.25~2.63。结论:MDCT右肘部静脉及下肢静脉同时注入对比剂,在动脉期扫描完成后,延时20.1±5.54 s行肝门静脉检查,肝门静脉系统成像效果良好。

The investigation of bi-pass way injection method to show hepatic portal system by multi-detector computed tomography

Objective:To determine reasonable delay time and feasibility of bi-pass way to inject contrast agent in hepatic portal system imaging.Methods: Two steps to study: ① 53cases without abdominal and cardiovascular disease were selected randomly.dynamic scan was performed after injected C.M.20ml in rate of 3ml/s.Draw the time-density-curve.② Forty-seven patients were performed dynamic scan after injected contrast agent to right elbow vein and lower extremity vein at the same time.Total dosage: 1.5～2ml/kg.Using contrast automatic tracing software,Setting the threshold of aterial vessel at 120Hu.hepatic portal system phase scan was performed after arterial phase scan 20.1±5.54 seconds.Results: ① In control group,the peak time of abdominal aorta was 18.5±4.81 s,hepatic portal vein was 38.61±6.59 s,inferior vena was 55.44±12.16 s,liver parenchyma was 56±5.7 s.②100% hepatic portal vein was displayed,the score of hepatic portal wein displaying was 2.50～2.93,the displaying rate of small broche was 87～98%. The score was 2.25～2.63.Conclusion: Inject contrast medium to right elbow vein and lower extremity vein at the same time using MDCT,hepatic portal vein scan time was 20.1±5.54 s delay after arterial phase.The image quality of hepatic portal vein system is satisfactory