螺旋CT双期扫描技术及其在胰腺癌诊断中的价值

目的：探讨螺旋CT双期扫描技术及其对胰腺癌的诊断价值。方法：正常人60例及胰腺癌44例分两组行螺旋CT双期扫描：A组40例，分动脉期和门动脉期（注射对比剂后20s和60s）扫描；B组64例，分胰腺期和肝脏期（注射对比剂后35s和70s)扫描。分别测定各期胰腺、病灶及胰周大血管的CT值，计算胰腺期及肝脏期胰周小静脉的显示率，并行统计学处理，对扫描时相的比较采用方差分析及q检验处理，对胰周小静脉的显示率采用x^2检验分析。结果：正常组，胰腺在胰腺期的增强值高于其他3期（F＝13．45，P＜0．0001）胰周大血管在胰腺期显示良好。胰周小静脉的显示率，胰腺期优于肝脏期（x^2=4．44，12．38，4．81，P＜0．05）；异常组，胰腺与病灶的增强差值，胰腺期明显大于其他3期（F＝14．90，P＜0．0001），发现小胰腺癌4例。胰周大血管受侵者占不可切除性肿瘤的54％（19／35），胰周小静脉迂曲扩张者占42％（10／42）。肝转移灶占37％（13／35）。结论：胰腺螺旋CT双期扫描宜分为胰腺期和肝脏期，该技术在胰腺癌的诊断中具有非常重要的临床价值。

Dual-phase spiral CT: technique and clinical value for pancreatic carcinoma

Objective　To study the protocols of dual-phase spiral CT for the evaluation of pancreatic carcinoma. Methods　One hundred and four patients(44 with pancreatic carcinoma, 60 with no upper abdominal disease) underwent dual-phase spiral CT. In group A, 40 patients were scanned for arterial and portal phase (20 and 60 s after intravenous infusion of contrast material at 3 ml/s) .In group B, 64 patients were scanned for pancreatic and hepatic phase(35 and 70 s). Mean CT attenuation value was obtained for normal pancreatic parenchyma, lesions and major peripancreatic blood vessels，respectively. The display rate of the small peripancreatic veins was calculated in the pancreatic and hepatic phase. All data were statistically analyzed. Results　In normal group, enhancement value of pancreas during the pancreatic phase was the greatest of all phases ［(118.10±17.78） HU, P<0.05］. Major peripancreatic vascular structures were visualized well in the pancreatic phase. The display rate of the small peripancreatic veins was higher in the pancreatic phase than in the hepatic phase (P<0.05). In abnormal group, the tumor-to-pancreas contrast difference was also the greatest during the pancreatic phase ［(65.89±28.81) HU, P<0.05］. Four cases of small cancer were found. It was identified that 54% of unresectable cases with major peripancreatic vessels invasion, 42% with small peripancreatic veins dilation, and 37% with metastatic hepatic neoplasms. Conclusion　In the dual-phase spiral CT protocol for pancreas, pancreatic and hepatic phase could be an optimal selection. It had an important value in diagnosing pancreatic carcinoma.