Findings: Plain Films: A supine plain film of the abdomen reveals a soft tissue mass in the region of the RUQ, superimposed over the region of the right kidney. Sonogram: Ultrasound demonstrates the classic "doughnut" sign or "target" sign with hypoechoic, edematous surrounding bowel representing the intussuscepiens and the central more echogenic, invaginated bowel representing the intussusceptum. Barium Enema: Initial pass of the barium column demonstrates free flow of contrast to the level of the intussusception—ileocecal valve. Ultimately, contrast medium flows freely into the terminal ileum with complete reduction of the ileocecal intussusception. The patient reintussuscepted, however, a second column of barium was introduced which successfully reduced the intussusception. A post-reduction film was obtained which confirmed successful reduction with an edematous ileocecal valve.

Diagnosis: Ileocolic Intussusception.

Discussion: Intussusception is an invagination of a segment of intestine into adjacent bowel. Intussusception may be ileocecal (most common), ileoileocolic, ileoileal or colocolic. Pathological lead points that may cause intussusception include Meckel’s diverticulum, inflamed appendix and polyps. Clinical symptoms are characterized by colicky abdominal pain and the child’s drawing the legs into the abdomen.

Obtaining supine, prone, supine horizontal-beam lateral views of the abdomen are useful to diagnose intussusception, exclude intussusception and to assess the safety and success of a potential radiographic reduction. The prone film aids in distinguishing small from large bowel and also distends the terminal ileum, cecal pole and ascending colon with air which is helpful in excluding ileocolic intussusception—which may be identified as an intraluminal mass on plain films.

Hydrostatic reduction with barium is the classic method for diagnosing and reducing intussusception. Contraindications are pneumoperitoneum and peritonitis. A bag of barium is hung three feet above the table top with a single column of barium flowing by gravity into the rectum and colon. The method advocated is the rule of 3s: 3 attempts; 3 minutes in duration; 3 foot barium column above the table top. If the reduction is unsuccessful, immediate surgery is necessary. Of course, ultrasound can be useful to diagnose intussusception—which is usually the first modality of choice to exclude intussusception in children.

References:
1. Kirks D. Practical Pediatric Imaging: Diagnostic Radiology of Infants and Children, 2nd edition. P878-888.

2. Swischuck L. Imaging of the Newborn, Infant and Young Child, 3rd edition, p456-461.

Return to Pediatric Imaging Page