X-ray changes seen when supine or prone:
(1) dilated gas or fluid filled small bowel > 3 cm in diameter
(2) dilated stomach
(3) small bowel dilated out of proportion to colon
(4) stretch sign (gas in small bowel arranged as low-attenuation stripes perpendicular to the long axis of the bowel, with gas separated by the valvulae conniventes)
(5) absence of rectal gas (nonspecific)
(6) gasless abdomen
(7) pseudotumor sign (obstructed, dilated and fluid-filled loops of small bowel)
X-ray changes seen when upright or in left lateral decubitus position:
(1) multiple air fluid levels
(2) air fluid levels longer than 2.5 cm
(3) air fluid levels in same loop of small bowel of unequal heights
(4) "string of beads" sign (fluid-filled loops of bowel with a small amount of gas trapped in the folds between vavlulae conniventes)
