Lipomatosis of the Ileocaecal Valve

This axial CT of the abdomen shows a fat-density rounded structure within the caecum. The terminal ileum can be seen medially. The patient can be seen to have plentiful intraabdominal fat. This represents lipomatosis of the ileocaecal valve, a normal variant seen most frequently in overweight females over 40.
The diagnosis is easy on CT, however with a barium enema the cause of the caecal filling defect may not be so obvious. The differential diagnosis in this case could include ileocaecal valve prolapse, adenomatous polyp, carcinoid tumour, or adenocarcinoma.
Many thanks to Dr Vijay Sadasivam for pointing out that the differential diagnosis also includes ileocaecal tuberculosis.

Reference: Dähnert W. Radiology Review Manual, 5th edition, Lippincott, Williams & Wilkins, 2003.

Credit: Dr Laughlin Dawes