Sonographic diagnosis of intussusception of the appendix vermiformis

We present 2 cases of intussusception of the appendix vermiformis (IAV) in children. Sonographic examination demonstrated a lead point within a charac teristic multiconcentric ring sign, and longitudinal sonograms showed the i nverted appendix protruding into the cecal lumen. A contrast-enema study, u sing a water-soluble contrast medium, was performed in each case, and a "co iled-spring" sign or "spiral shell" appearance confirmed the diagnosis. A s urgical reduction of the appendix and an appendectomy were performed in eac h case. (C) 2000 John Wiley & Sons, Inc.