Objective: The purpose of this prospective study was to evaluate the role of CT in the diagnosis of patients with suspected acute small-bowel obstruction in whom clinical and plain radiographic findings were inconclusive.
Subjects and methods: Fifty-seven nonconsecutive patients with suspected acute small-bowel obstruction were referred for CT to differentiate small-bowel obstruction from ileus (33 patients) or to establish the cause of obstruction (24 patients). The final diagnosis was established either by surgery (42 patients) or by the clinical evolution (15 patients). The change in the prescan diagnosis as to the presence, cause, and severity (strangulation) of small-bowel obstruction made on the basis of the CT findings was noted. Finally, the changes in therapy resulting from the CT information were recorded.
Results: CT correctly distinguished between small-bowel obstruction and ileus in all cases except one. CT enabled us to modify an erroneous clinical diagnosis correctly in 12 (21%) of 57 cases, including eight cases for which pre-CT diagnosis was ileus and four cases for which pre-CT diagnosis was small-bowel obstruction. CT allowed us to predict the cause of obstruction correctly in 33 (85%) of 39 patients with confirmed small-bowel obstruction but it failed to differentiate adhesions from internal hernias and radiation enteritis. The pre-CT diagnosis of the cause of obstruction was correctly changed because of CT findings in 17 (44%) of 39 patients with subsequently proved small-bowel obstruction. CT was able to identify strangulation in nine of the 12 patients with proved strangulation, which altered the pre-CT diagnosis in three patients. CT findings correctly modified the management in 12 (21%) of 57 patients, by changing either a conservative management to an operative one in 10 (18%), or an operative to a conservative one by differentiating ileus from obstruction in two patients.
Conclusion: Our findings show that CT is a valuable diagnostic procedure in patients with suspected acute small-bowel obstruction. CT not only is useful in distinguishing obstruction from paralytic ileus, but it frequently establishes the cause of the obstruction and the presence of strangulation. CT findings lead to decisions to treat patients surgically in a significant number of patients.