Size of gas-filled bowel loops in infants.

The width of the largest gas-filled bowel loop was measured and numerically divided by measurements of vertebral spine elements as seen on supine abdominal radiographs of 375 infants without suspected abdominal disease. This technique adjusts the bowel diameter for patient size, and permits numerical description of varying degrees of distension. Normal standards are presented, as are the larger values seen with suspected and proved necrotizing enterocolitis and congenital obstructions. The width of the first lumbar vertebral body provides a useful approximation of the upper limit of normal bowel diameter.