GI Radiology > Small Bowel > Disease Patterns > Small Bowel Obstruction

Structural Abnormalities

Small Bowel Obstruction

Radiographic - CT

• CT is a valuable adjunct to fluoroscopy in the evaluation of SBO.


• CT detects intramural or extraintestinal causes of SBO, such as hernias, masses, etc.


• CT assists in determining the site of obstruction. The site of obstruction is often heralded by a transition zone, in which the caliber of the bowel wall transforms from dilated to decompressed.


• Hernias - CT may demonstrate abnormal location of small bowel and help to defines other hernia contents (e.g. omentum, colon).


• Volvulus - CT may demonstrate radially distributed dilated small bowel around twisted, edematous mesentery.


• Intussusception - CT shows edematous bowel walls with a bull's eye appearance from the layering of bowel walls.