Case gg -  Small bowel obstruction with closed loop

The proximal small bowel is dilated and there are air fluid levels.  The distal bowel is completely decompressed.  This is a small bowel obstruction.  It is now your job to find the transition point.

The transition point is in the left upper quadrant.  I believe this is actually a closed loop.  The bowel loop is dilated and appears to taper at the transition point..  This adjacent segment of bowel is dilated and loops back onto itself at the transition point.  Thus, at the transition there are three dilated loops of bowel and one decompressed loop. This is a closed loop obstruction.  Scroll through this area until you understand the anatomy. Note that even though contrast has not progressed to the transition point, it is still easily identifiable.

Although there is a closed loop, the bowel is not thickened.  There is no surrounding ascites.  There is a small amount of pelvic fluid which may or may not be related.

Incidental note is made of an IVC filter, hepatic cysts, and a cystic pancreatic neoplasm.

Take home point

• If you see dilated proximal bowel look for decompressed distal bowel.  This is an small bowel obstruction.  You have your diagnosis.  Now look for a transition point, a closed loop, or signs of ischemia such as ascites or bowel wall thickening.