小肠梗阻伴缺血多排螺旋CT特异性征象分析

Specific signs of multi-row spiral CT of small bowel obstruction complicated with ischemia

目的 探讨小肠梗阻伴缺血的多排螺旋CT特异性征象。方法 39例小肠梗阻患者,其中伴缺血者21例为缺血组,不伴缺血者18例为非缺血组,2组均于术前行CT平扫及增强扫描,比较2组平扫肠壁密度增高、增强肠壁密度减低、肠壁增厚、靶征、闭袢形成、漩涡征、肠壁积气、门静脉或肠系膜静脉积气、肠系膜脂肪密度增高、鸟嘴征、腹腔积液、小肠粪征出现率,logistic回归模型分析小肠梗阻患者出现缺血的特异征象。结果 2组均未出现肠壁积气、门静脉或肠系膜静脉积气征象,余10个征象中缺血组平扫肠壁密度增高（28.6%）、增强扫描肠壁密度减低（61.9%）、肠壁增厚（57.1%）、肠系膜脂肪密度增高（90.5%）、鸟嘴征（100%）出现率高于非缺血组（0、11.1%、22.2%、44.4%、66.7%）（P〈0.05）,2组靶征、闭袢形成、漩涡征、腹腔积液、小肠粪征出现率比较差异无统计学意义（P〉0.05）;多因素logistic回归分析结果显示,增强扫描肠壁密度减低（OR=7.934,95%CI：1.300~48.434,P=0.025）、肠系膜脂肪密度增高（OR=6.666,95%CI：1.045~42.534,P=0.045）与小肠梗阻患者出现缺血有关。结论 多排螺旋CT增强扫描显示肠壁密度减低、肠系膜脂肪密度增高是小肠梗阻患者伴缺血的2个特异性征象。

Objective To analyze multi-row spiral CT signs of small bowel obstruction complicated with ischemia and evaluate its diagnostic value. Methods In 39 patients with small bowel obstruction, there were 21 patients with ischemia （ischemia group） and 18 patients with no ischemia （non-ischemia group）. Both two groups underwent CT plain scan and contrast enhancement. Two groups were compared the increased unenhanced bowel wall attenuation, decreased bowel wall enhancement, bowel wall thickening, target sign, closedcloop obstruction, whirl sign, pneumatosis intestinalis, gas bubbles in the portal vein or mesenteric veins, mesenteric fat stranding, beak sign, ascites and small bowel feces sign. The specific signs of small bowel obstruction complicated with ischemia were statistically analyzed by logistic regression model. Results No pneumatosis intestinalis or gas bubbles in the portal vein and mesenteric veins occurred in two groups. The incidences of the remaining ten signs as increased unenhanced bowel wall attenuation （28.6 %）, decreased bowel wall enhancement （61.9%）, bowel wall thickening （57. 1%）, mesenteric fat stranding （90. 5%） and beak sign （100%） were significantly higher in ischemia group than those in non-isehemia group （0, 11. 1%, 22.2%, 44. 4%, 66.7 %） （P〈0.05）. There were no significant differences in the incidences of target sign, closed-loop obstruction, whirl sign, ascites and small bowel feces sign between two groups （P〉0.05）. Multivariable logistic regression analysis showed the decreased bowel wall enhancement （OR=7. 934, 95%CI： 1. 300 to 48. 434, P=0. 025） and mesenteric fat stranding （OR=6. 666, 95%CI： 1. 045 to 42. 534, P=0. 045） were correlated with small bowel obstruction complicated with ischemia. Conclusion Multi-row spiral CT enhanced scan suggests the decreased bowel wall enhancement and mesenteric fat stranding might be the two specific signs in small bowel obstruction complicated with ischemia.