Key findings:

• Oral contrast in stomach
• Mildly dilated proximal small bowel with gradual admixture of oral contrast with enteric fluid as the bowel progresses distally.
• Two adjacent angulated transition points indicate th "closed loop" segment, and form a "waist"-like appearance in the right mid abdomen on the axial images. 
• The closed loop portion is dilated, fluid-filled, and has mesenteric edema/interloop fluid.
• Notice how there is mesenteric edema involving the closed loop, but not the proximal small bowel.

Diagnosis: Closed loop small bowel obstruction due to adhesive bands

Click here for the intraoperative photo showing the adhesive band

Discussion:

There are several subtle clues indicating a closed-loop obstruction in this case. The proximal small bowel is mildly dilated, but less so that then closed loop segment in the right lower quadrant. The small bowel in the closed loop sticks out as more abnormal than any other segment in the abdomen: more dilated, no oral contrast, and mesenteric edema. The axial images give it away (see annotated image) - the two sites of obstruction are adjacent to each other, indicating a closed loop obstruction. This appearance could be due to internal hernia or (as in this case) adhesive bands.