Dilated small bowel loops are loops of the small bowel, distended and filled with air and fluid, that are associated with an obstruction in the bowel. They locate toward the beginning of the obstruction, which is frequently related to an adhesion from a prior surgery, according to the online textbook Learningradiology.com.
Dilated smalI bowel loops are usually greater than 3 centimeters in size. Images may show small bowel loops appearing in a ladder formation, which can also indicate an obstruction of the colon, or looking like a string of beads when a small amount of gas is visible. The air/fluid levels present in the loops are significant when diagnosing the type of obstruction, although regular X-rays may not be adequate to diagnose low-grade obstructions, according to the National Institutes of Health.
Small bowel obstructions are usually mechanical obstructions, as reported in the Merck Manual. Blockage occurs and then food and fluid that have been consumed along with gas and other gastric fluids build up above the blockage. This is also where dilated loops occur. Collapsed loops are found on the other, distal side of the blockage. Pain, vomiting and distention of the abdomen are typical symptoms of small bowel obstruction.