Toddler with crampy abdominal pain

US of ileocolic intussusception
AXR (left) was unremarkable. Sagittal US of the right lower quadrant (middle) showed a pseudokidney sign in the ascending colon. Air enema encountered a mass at the ileocecal valve which was rapidly reduced with reflux of a large amount of air into the terminal ileum (right).

The diagnosis was ileocolic intussusception.