The role of computed tomography for identifying mechanical bowel obstruction in a Pakistani population.

OBJECTIVE To retrospectively review our experience of CT scan in cases with a final diagnosis of surgically confirmed mechanical bowel obstruction. METHODS It is a retrospective analytical study, done from 2003 to 2008. All adult patients having undergone laparotomy in addition to a preoperative abdominal CT scan over a 5 year period were identified through the medical records and their case notes reviewed. Taking surgery to be the gold standard for diagnosing mechanical bowel obstruction, we compared results of the CT with operative findings to determine the sensitivity, specificity, positive and negative predictive values of CT scans. The data was analyzed using SPSS version 16.0. RESULTS A total of 271 patient records were reviewed. The mean age was 46 +/- 19 years and (64%) were men. Mechanical intestinal obstruction was found in 104 patients on laparotomy and CT scan had diagnosed 97 of these. The sensitivity and specificity was 93% respectively. CT scanning correctly identified the cause of the obstruction in 72 (74%) cases. The common reasons for bowel obstruction identified by surgery were adhesions 29 (40%), neoplasm 12 (17 %) and hernias 7 (10%). CONCLUSION CT scans are reliable at diagnosing intestinal obstruction with a high sensitivity and specificity but they are not as accurate at defining the etiology of the obstruction.