Abd

Film abdomen

1 • Look at the fixed anatomy. Do not forget the lungs.

Gas Distribution. • Obstruction: • Too much air in the small bowel (and not much gas in the large bowel) or too much air in the large bowel (and not much gas in the small bowel). Poor gas distribution or gasless.

Gas Distribution. • Ileus: Good gas distribution over most of the abdomen. Too much air in both large and small bowel. Warning: This could also appear in large bowel obstruction with an incompetent ileocecal valve, or in an early or intermittent small bowel obstruction.

Bowel Dilatation. • Obstruction: Smooth bowel walls (resembles sausages or a hose). Preferential dilatation of the bowel proximal to the obstruction.

Bowel Dilatation • Ileus: Dilatation of the bowel in proportion to each other, so that the colon remains larger than the small intestine. Look for sentinel loops.

Air-fluid Levels. • Obstruction: Many dilated air-fluid levels in both limbs of a given loop, at different heights (candy canes)

Air-fluid Levels. • Ileus: Fewer and/or smaller (less dilated) air-fluid levels scattered throughout the abdomen.

Arrangement of loops (supine view only). • Obstruction: Dilated loops arranged in "stepladder" fashion. Orderly. A bag of sausages • Ileus: Disorderly loops scattered throughout the abdomen. A bag of popcorn.