CT evaluation of small bowel obstruction

Although small bowel obstruction is a common occurrence, it is essential that this clinical condition be treated properly, that the site, level, and cause of obstruction be determined accurately, and that a tentative prognosis be formulated prior to surgery. The diagnosis of small bowel obstruction is based on a comprehensive approach that includes clinical background, patient history, and results of physical examination and laboratory tests. A variety of radiologic procedures are available to aid in the diagnosis of small bowel obstruction. Recent studies have demonstrated the superiority of CT in revealing the site, level, and cause of obstruction and in demonstrating threatening signs of bowel inviability. CT has proved useful in characterizing small bowel obstruction from extrinsic causes (adhesions, closed loop, strangulation, hernia, extrinsic masses), intrinsic causes (adeno carcinoma, Crohn disease, tuberculosis, radiation enteropathy, intramural hemorrhage, intussusception), intraluminal causes (eg, bezoars), or intestinal malrotation. Conventional radiography was the modality of choice for many years and should remain the initial imaging method in patients with suspected small bowel obstruction. However, the unique capabilities of CT in this setting make this modality an important additional diagnostic tool when specific disease management issues must be addressed.