不同扫描时相小肠CT造影显示效能研究

A comparative study for the effectiveness of the image by multiphase CT enterography among three scan phases

目的比较CT造影在不同扫描时相下对小肠肠壁及血管的显示效果,确定最佳扫描时相,评价该时相的临床诊断效能。方法将286例行小肠CT造影的住院患者分别进行动脉期、肠道期及门脉期扫描,测量十二指肠、空肠及回肠肠壁CT值、血管显示数量及血管CT值,比较分析后选择最佳扫描时相,评价该时相CT图像小肠及血管病变的诊断效能。结果 (1)十二指肠、空肠及回肠肠壁CT值均为肠道期高于动脉期和门脉期(P<0.05),而动脉期和门脉期差异无统计学意义。(2)回肠动脉在各时相CT值比较:动脉期>门脉期,肠道期与动脉期、门脉期差异无统计学意义。回肠静脉在各时相CT值比较:肠道期>门脉期>动脉期(P<0.05)。(3)小肠CT造影诊断小肠疾病的灵敏度为95.8%,特异度为94.9%,正确率为95.1%,阳性预测值为79.3%,阴性预测值为99.1%。(4)小肠CT造影证实小肠淋巴瘤22例、间质瘤10例、腺瘤1例、血管瘤3例、克罗恩病8例、小肠结核1例、缺血性肠病3例,对于血管瘤的诊断需结合动脉期。结论小肠CT造影肠道期对小肠肠壁及血管有较好的显示效能,利用动脉期及肠道期双期扫描方式进行小肠CT造影检查,可对大多数小肠疾病做出准确诊断。

Objective To evaluate the influence of the CT enterography （CTE） in different scan phases of small intestinal wall and arteriovenous vessels, and to confirm the diagnostic efficiency thereof. Methods A total of 286 patients underwent CTE were collected, and their CT image of three scan phases, including 20 s, 40 s and 60 s after injection, were recorded. Values of reinforcement of the intestinal wall and arteriovenous enhancing degree in all phases were collected. A statistical analysis was used to confirm the best phase for showing the structure. The diagnostic efficiency of the best phase of CT image was evaluated for the clinical diagnosis of small intestine and vascular lesions. Results （1） The CT value of the small intestinal wall in the intestinal phase was significantly higher than other two phases （P〈0.05）. There was no significant difference in CT value between arterial phase and portal phase. （2） Comparison between three phases of CT values of ileum showed that artery：arterial phase〉intestinal phase, and there is no statistical difference between the intestinal phase and other two phases. The result of CT value of ileum vein showed that intestinal phase〉portal phase〉arterial phase （P〈0.05）. （3） The sensitivity was 95.8%, the specificity was 94.9%, the accuracy was 95.1%, the positive predictive value was 79.3%and the negative predictive value was 99.1%using CT image of intestinal period for diagnosing small intestinal diseases. （4） The intestinal period showed small intestinal lesions and confirmed by pathology including 22 cases of small intestinal lymphoma, 10 cases of stromal tumor, 1 case adenoma, cavernous 3 cases hemangioma and 8 cases of Crohn＇s disease. The diagnosis of hemangioma should be combined with arterial phase. Conclusion Small intestinal wall and blood vessels have better display performance in the intestinal phase of multiphase CT enterography, using the arterial phase and intestinal phase scanning, we can make an accurate diagnosis for the majority of small intestinal diseases.