CT diagnosis of traumatic small bowel perforation without pneumoperitoneum or oral contrast leak

To determine the most helpful abdominal CT findings in patients with small bowel perforation without pneumoperitoneum or oral contrast leakage after blunt trauma. We retrospectively analyzed the abdominal CT findings of 51 patients with small bowel perforation without pneumoperitoneum or oral contrast leakage. A score of 2 was assigned if bowel wall thickening of more than 5 mm or enhancement of the bowel wall was definite, and 1 if equivocal thickenting or enhancement of the bowel wall, mesenteric infiltration, sentinel clotting, intermesenteric fluid, or ileus were observed. According to the score, each finding was classified as strongly positive(5-8), possibly positive(3-4), or probably negative(1-2), and the accuracy of each classification was evaluated. We decided which findings would be most helpful when attempting to diagnose small bowel perforation. Forty one bowel perforations and four mesenteric injuries were identified in 45 laparatomies among 51 patients. In all 20 patents with a score of more than 5, small bowel perforation was found on surgery. The prevalence rate of bowel wall thickening and enhancement was significantly different between patients with perforation(88%, 80% respectively) and those without (20%, 40% respectively)(p<0.05). The sensitivity, specificity and accuracy of each criterion were compared (sum of scoring of all CT findings≥3D3:82.9% · 40% · 74.5%;scoring of bowel wall thickening and enhancement ≥3D 2:82.9% · 80% · 82.4%), and it was found that for specificity and accuracy, the latter was superior to the former. ROC analysis using the scores of each criterion as cut-off value also showed that the curve of the latter showed a more marked upward trend and was the most helpful parameter. When diagnosing small bowel perforation in the absence of pneumoperitonemum or oral contrast leakage after blunt abdominal trauma, bowel wall thickening and enhancement were more helpful parameters than the sum of all CT findings.=20