An abdominal x-ray with barium meal (small bowel series) may be helpful in the diagnosis of ileus. Findings on an x-ray suggestive of ileus include multiple air–fluid levels throughout the abdomen, elevated diaphragm with dilatation of both large and small intestine, slow movement of barium with a patent intestinal lumen. Serial x rays may also differentiate paralytic ileus from mechanical intestinal obstruction.

An supine upright abdominal x-ray with or without barium meal (small bowel series) may be helpful in the diagnosis of ileus. Findings on an x-ray suggestive of ileus include:^[1][2]

• Multiple air–fluid levels throughout the abdomen.
• Elevation of diaphragm.
• Dilatation of both large and small intestine with no transition point.
• Slow movement of barium with a patent intestinal lumen.
• Serial x rays may show non progressive distension as compared to progressive distension seen in case of mechanical obstruction .
• Serial x rays can also be used to detect the resolution of ileus which proceed in proximal to distal fashion. The return of propulsive activity to the right colon occurs earlier than to the transverse or left colon.

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