Beattie Garth C, Peters Robert T, Guy Susanne, Mendelson Richard M
Department of Colorectal Surgery, Royal Perth Hospital, Perth, Western Australia, Australia.
ANZ J Surg. 2007 Mar;77(3):160-5. doi: 10.1111/j.1445-2197.2006.03998.x.
The aim of this study was to assess the efficacy of computed tomography (CT) scanning in the diagnosis of acute large bowel obstruction.
Forty-four patients (22 men; 22 women, ages 39-94 years, mean 71 years) with clinical features and abdominal radiographic findings suggesting acute large bowel obstruction (LBO) or pseudo-obstruction were examined with CT. Supine scans were obtained with i.v. contrast medium (unless contraindicated), but (in the majority) without oral contrast. Additional prone and/or decubitus scans were obtained in 33 patients when clarification of a possible transition point on the supine scan was required. CT diagnosis of LBO was made by finding a transition point +/- mass. Final diagnosis was confirmed by surgery, further imaging and/or clinical course.
Twenty-two patients had proven mechanical acute LBO of whom 18 had an obstructing carcinoma; 22 patients had no mechanical obstruction. Sensitivity, specificity, Positive Predictive Value, Negative Predictive Value of CT for diagnosis of mechanical LBO were each 91%. Positive and negative likelihood ratios were 10.1 and 0.1, respectively. There were two false-negative CT scans, although one of these was reported as showing segmental mural thickening. A mass was identified on 14 of 17 patients with true-positive CT, subsequently found to have carcinoma.
Computed tomography with additional selective prone and/or decubitus scanning is highly effective in the diagnosis of mechanical LBO. It is suggested that it replace contrast enema as the initial imaging method.
本研究旨在评估计算机断层扫描（CT）在诊断急性大肠梗阻中的有效性。
对44例（22例男性；22例女性，年龄39 - 94岁，平均71岁）具有提示急性大肠梗阻（LBO）或假性梗阻的临床特征及腹部X线表现的患者进行CT检查。仰卧位扫描时静脉注射造影剂（除非有禁忌证），但（大多数情况下）不口服造影剂。当需要明确仰卧位扫描上可能的移行点时，33例患者进行了额外的俯卧位和/或侧卧位扫描。通过发现移行点±肿块来做出LBO的CT诊断。最终诊断通过手术、进一步影像学检查和/或临床病程得以证实。
22例患者被证实为机械性急性LBO，其中18例有梗阻性癌；22例患者无机械性梗阻。CT诊断机械性LBO的敏感性、特异性、阳性预测值、阴性预测值均为91%。阳性似然比和阴性似然比分别为10.1和0.1。有2例CT扫描结果为假阴性，尽管其中1例报告显示节段性肠壁增厚。在17例CT真阳性的患者中，有14例发现了肿块，随后证实为癌。
计算机断层扫描结合额外的选择性俯卧位和/或侧卧位扫描在诊断机械性LBO方面非常有效。建议将其作为初始影像学检查方法取代钡剂灌肠。
