多层螺旋CT胰腺检查:不同注射条件下时间窗的选择

Multislice spiral CT in Pancreas Examination: Optimal Temporal Window at Different Injection Rates and Doses

目的探讨多层螺旋CT胰腺三期增强扫描,不同注射条件下时间窗的选择。资料与方法40例无胰腺疾病患者,随机分为A、B两组各20例,A组注射条件为:对比剂总量为120ml,注射流率为5ml/s;B组注射条件为:对比剂总量为90ml,注射流率为3ml/s。行胰腺同层动态增强扫描,于不同时间点,分别测定胰腺、肝脏实质及胰周主动脉、门静脉的CT值,最后分别绘制时间密度曲线。结果两组胰周主动脉强化到达峰值的平均时间分别为(33.2±3.8)s(A组)及(40.1±3.8)s(B组),而20s(A组)及25s(B组)时胰周动脉CT值多可达200HU;胰腺实质强化到达峰值的平均时间分别为(42.7±3.3)s(A组)及(46.8±4.5)s(B组);胰周门静脉强化到达峰值的平均时间分别为(47.5±4.8)s(A组)及(53.3±4.8)s(B组);肝脏实质强化到达峰值的平均时间分别为(59.2±4.7)s(A组)及(64.2±4.5)s(B组)。结论在不同的注射条件下,多层螺旋CT胰腺检查三期增强扫描的时间窗的设定并不相同。笔者推荐,对比剂总量为120ml,注射流率为5ml/s时,动脉期延迟时间为20s,胰腺期延迟时间为45s,肝脏期延迟时间为65s;对比剂总量为90ml,注射流率为3ml/s时,动脉期延迟时间为25s,胰腺期延迟时间为50s,肝脏期延迟时间为65s。

Objective To discuss the optimal temporal window at different injection rates and doses in triple-phase enhanced scan of pancreas multislice spiral CT examination.Materials and Methods 40 patients without pancreatic disease were bisected at random. The injection rate was 5ml/s for group A and 3ml/s for group B, and the injection dose was 120ml for group A and 90ml for group B. They all were underwent with single-level enhanced serial CT scanning of pancreas, then CT value of the peripancreatic aorta and portal vein, pancreatic and hepatic parenchyma were measured respectively in different time. Results The average peak enhancement time of the peripancreatic aorta was (33.2±3.8)s (group A) and (40.1±3.8)s (group B), and their CT value mostly exceeded 200HU at 20s (group A) and 25s (group B). The average peak enhancement time for the pancreatic parenchyma was (42.7±3.3)s (group A) and (46.8±4.5)s (group B), as well as (47.5±4.8)s (group A) and (53.3±4.8)s (group B) for the peripancreatic portal vein, (59.2±4.7)s (group A) and (64.2±4.5)s (group B) for the hepatic parenchyma. Conclusion The optimal delay time in triple-phase enhanced scan of pancreas examination was different at different injection rates and doses. When the injection dose was 120ml and the injection rate was 5ml/s, it is recommended that the delay time was 20s for arterial phase, 45s for pancreatic phase and 65s for liver phase. If the injection dose was changed to 90ml and the injection rate was 3ml/s, 25s for arterial phase, 50s for pancreatic phase and 65s for liver phase.