Newborn with failure to pass meconium

AXR of anorectal malformation
AXR (above) shows multiple dilated loops of bowel within the abdomen that are progressively more dilated as they near the rectum. Prone cross-table lateral radiograph of the abdomen obtained after 10 minutes in the prone position (below) with a radio-opaque BB on the anus shows a short distance between the anus and the gas in the rectum.

The diagnosis was a low anorectal malformation.