口服对比剂对肝外胆道梗阻病变CT重组及诊断的影响

Influence of bowel preparation by oral contrast medium in the computed tomography reforming and diagnosis of extrahepatic biliary obstruction

目的研究不同口服对比剂及其服用方法对肝外胆道梗阻病变CT重组和诊断的影响。方法分析198例胆道梗阻病例CT资料和重组图像。根据口服不同的肠道对比剂分为阴性组(水溶液或等渗甘露醇)和阳性组(2%泛影葡胺溶液),根据服用方法是否指导分为随机组和指导组,分别判断其肠道准备满意度并进行统计分析。对CT扫描数据进行薄层重建和MPR,CPR,MinIP及VR后处理重组,判断图像满意率和诊断准确率,并进行统计学分析。结果阳性组(87.60%)和阴性组(90.30%)图像显示满意率无显著差别(x2=0.365,P>0.05)。指导组(95.89%)比随机组(80.08%)图像显示满意率高,差别有统计学意义(x2=8.911,P<0.05)。肠道口服对比剂准备满意组定位诊断准确率为96.49%,定性准确率为95.45%。不满意组定位诊断准确率为59.26%,定性准确率为55.56%。满意组比不满意组定位(x2=493.789,P<0.05)和定性(x2=490.669,P<0.05)准确率高,差别有统计学意义。结论胆道梗阻病变CT扫描前合理的肠道对比剂准备方法是采用指导下的分段口服法。肠道对比剂准备满意者有助于提高胆道梗阻病变的定位和定性诊断准确率。

Objective To study the influence of different bowel preparation by oral contrast medium in the computed tomography reforming and diagnosis of extrahepatic biliary obstruction. Methods CT scan data and post-process reforming images including MPRf-CPRf-MinIP and VR in 198 cases with extrahepatic biliary obstructions were analyzed. Negative group（water or isotonic mannite） and positive group （ 2% meglucamine diatrizoate ） were divided into according to the administration of different oral contrast medium. Two groups including random group and instructive group were also analyzed depend on whether the patients were given instructive information or not on how to take the oral contrast medium properly. Statistic analysis were done respectively according to the satisfaction ratio of bowel preparation and the quality of CT reforming imaging and the accuracy of localizing and qualitative diagnosis. Results There was no significant difference statistically between negative group （ 87.60% ） and positive group （ 90.30% ） on the satisfaction ratio of reforming imaging （ Х^2= 0.365, P〉0.05 ）, but significant difference between random group （ 80.08% ） and instructive group （ 95.89% ） （ Х^2= 8.911, P〈0.05 ）. The accuracy of localizing and qualitative diagnosis for patients with satisfied bowel preparation were 96.49% and 95.45% respectively. Whereas the accuracy of localizing and qualitative diagnosis for patients with unsatisfied bowel preparation were 59.26% and 55.56% respectively. There was statistically significant difference between them on the accuracy of localizing diagnosis （Х^2= 493.789, P〈0.05） and qualitative diagnosis （Х^2= 490.669, P〈0.05）. Conclusion The bowl preparation for CT scanning by oral contrast medium separated into two subsections with instructive inlormation for patients with extrahepatic biliary obstruction could be a good alternative. Satisfied bowel preparation may provide a valuable clue to the accurate diagnosis of localizing and qualitative ofextrahepatic biliary lessions.