Approximately 4% of all patients evaluated in emergency departments with acute abdominal pain are ultimately diagnosed with bowel obstruction. Suspected intestinal obstruction accounts for 20% of all surgical admissions in patients presenting to emergency departments with acute abdominal pain. Approximately 60% to 85% of cases of obstruction occur in the small bowel, 10% to 15% in the colon, and the remainder in the stomach and the esophagus.
The traditional methods for evaluating and diagnosing suspected intestinal obstruction are the clinical history, physical examination, and supine and erect radiographs of the abdomen. However, using these techniques, the diagnosis is not established in 30% to 40% of cases. CT has emerged as a valuable tool in the assessment of these patients. A single CT study can answer the most significant questions a clinician is confronted with in assessing these patients by: (1) establishing the diagnosis of obstruction, (2) determining the location and cause of the obstruction, (3) assessing for the presence of ischemia, and (4) aiding in timing of surgical therapy.
This article reviews the imaging findings used to establish the diagnosis, etiology, and complications of acute small bowel obstruction. The major focus relates to CT evaluation.