Neonatal ileocolic intussusception with enterogenous cyst: ultrasonic diagnosis.

An eight-day-old girl had sonography performed to rule out pyloric stenosis because of recurrent vomiting and a right upper quadrant mass. Caudal to the normal pylorus sonography demonstrated an elongated mass containing two hypoechoic rings with a cyst at the end of it. An ileocolic intussusception was then diagnosed by a barium examination. Surgery confirmed the diagnosis, the leading mass being a duplication cyst.