多层螺旋CT薄层扫描在消化道穿孔定位诊断中的价值

The value of multi-slice spiral CT thin slice scanning in localization diagnosis of digestive tract perforation

目的评价多层螺旋CT在消化道穿孔定位诊断中的价值。方法回顾性研究44例经手术证实消化道穿孔患者CT薄层图像,部分病例进行薄层图像重组观察,分析不同部位消化道穿孔游离气体分布位置;依据消化道穿孔不同影像征象对穿孔部位定位并与手术结果进行比较,统计诊断符合率。结果上消化道穿孔游离气体出现位置依次为:前腹壁下21例、肝门静脉区15例、肝裂12例、小网膜囊10例、腹膜后2例、肠系膜区1例;下消化道穿孔游离气体出现位置依次为:肠壁外系膜区8例、前腹壁下8例、盆腔7例、小网膜囊6例、肝门静脉区6例、肝裂2例。门静脉区游离气体征阳性诊断上消化道穿孔的准确性为71.4%(15/21),肠系膜区或盆腔内游离气体征阳性诊断下消化道穿孔的准确性为84.6%(11/13)。CT诊断消化道穿孔符合率为88.6%(39/44),定位诊断符合率为72.7%(32/44)。胃肠壁外小气泡(n=21)、胃肠壁局部破口(n=6)、胃肠壁局限性增厚(n=23)、局限性或包裹性积液(n=5)有助于准确定位影像征象,根据上述影像征象评估破口位置并与手术结果比较,符合率分别为90.4%(19/21)、100%(6/6)、91.3%(21/23)、80.0%(4/5)。结论多层螺旋CT薄层扫描对消化道穿孔的定位诊断有重要价值,胃肠壁局限性改变、肠壁外小气泡、局限性或包裹性积液有助于对消化道穿孔部位准确定位。

Objective To evaluate the value of multi-slice spiral CT in localization diagnosis of digestive tract perforation. Methods The CT thin layer images of 44 patients confirmed with digestive tract perforation were retrospectively studied,with restructuring observation of thin layer images conducted for some cases,and the distribution location of free gas in digestive tract perforation of different parts were analyzed; the perforating parts were located based on different image symptoms of digestive tract perforation,the results were compared with the operation,and the diagnostic accordance rate was counted. Results The positions where the free gas in upper digestive tract perforation appeared were as follows,21 cases under anterior abdominal wall,15 cases in hepatic portal vein area,12 cases of fissure,10 cases of lesser peritoneal sac,2 cases of retroperitoneum and 1 case in mesentery area; the positions where the free gas in lower digestive tract appeared were as follows： 8 cases of intestinal wall outer mesentery area,8 cases under anterior abdominal wall,7 cases in pelvic cavity,6 cases of lesser peritoneal sac,6 cases of hepatic portal vein area,and 2 cases of fissure. For free gas symptom in portal vein area,the accuracy rate of positive diagnosis in upper digestive tract perforation was 71. 4%（15/21）,and for free gas symptom in mesentery area or pelvic cavity,the accuracy rate of positive diagnosis in lower digestive tract perforation was 84. 6%（11/13）. The coincidence rate of CT diagnosis in digestive tract perforation was 88. 6%（39/44）,and the coincidence rate of localization diagnosis was 72. 7%（32/44）. Small bubbles outside gastrointestinal wall（n = 21）,partial crevasse of gastrointestinal wall（n = 6）,local thickness of gastrointestinal wall（n = 23）,and local or encapsulated effusion（n = 5） were conducive to localize the image accurately. According to above image symptom,the locations of crevasse were evaluated and compared with operation results,and the coincidence rates were 90. 4%（19/21）,100%（6/6）,91. 3%（21/23）,and 80. 0%（4/5）,respectively. Conclusion Multislice spiral CT thin-layer scanning has important value to the localization diagnosis of digestive tract perforation. Limited alteration of gastrointestinal wall,small bubbles outside gastrointestinal wall,local or encapsulated effusion are helpful for the accurate location of digestive tract perforation.