CT of small-bowel obstruction in children: Sensitivity and specificity

OBJECTIVE, The aim of this study was to determine the sensitivity, specific ity, and accuracy of CT in the diagnosis of small-bowel obstruction in chil dren. MATERIALS AND METHODS. The CT scans of 30 children with surgically proven s mall-bowel obstruction, 22 children with ileus, and 29 children who served as controls were retrospectively reviewed by two of four interpreters who w ere unaware of the children's final diagnoses. Causes of obstruction in the patients included 19 adhesions, six cases of volvulus, five intussusceptio ns, four strictures, and two cases each of internal hernia and abscess. Eig ht obstructions had multiple causes. The CT scans were evaluated for the pr esence of small-bowel obstruction using a scale with five degrees of confid ence. In cases of discrepancy of more than one level of certainty, a third interpreter was consulted. Criteria for small-bowel obstruction included a discrepancy in caliber between the proximal dilated and the more distal sma ll bowels pr generalized small-bowel dilatation (>2.5 cm) in the presence o f a collapsed colon. An interpreter's rating that an obstruction was either present or probable was considered a positive finding; a rating indicating that the interpreter was not sure whether an obstruction was present. or b elieved that an obstruction was not probable or saw normal anatomic structu res was considered a negative finding for small-bowel obstruction. The caus e and level of obstruction also were recorded. RESULTS. There were 26 true-positive (87%) and four false-negative (13%) in terpretations for small-bowel obstruction. Among the interpretations of sca ns of patients with ileus, 68% were true-negative and 32% were false-positi ve interpretations for small-bowel obstruction. Among the control group, th ere were no false-positive readings. Sensitivity of CT was 87%, specificity was 86%, and accuracy was 86%. In the scans of children 2 years and younge r, CT had a sensitivity of 100% and specificity of 0%. Of the patients with surgically confirmed levels of obstruction, the correct level of obstructi on was described by both interpreters in 12 (86%) of 14 scans. The causes o f obstruction were correctly identified in 14 (47%) of 30 scans. CONCLUSION. CT is both sensitive and specific for use in diagnosing small-b owel obstruction in children, especially in children older than 2 years.