Imaging of transmural migration of a retained surgical sponge: a case report.

A 61-year-old woman who had undergone a hysterectomy 15 years before this presentation had suffered from intermittent abdominal pain and a palpable lower abdominal mass for 3 months. Plain roentgenography revealed a radiopaque mass with serpiginous density in the pelvic region. Sonography showed curvilinear hyperechogenicity with an acoustic shadow. A small-bowel series revealed a huge amorphous filling defect inside the ileum. Computed tomography showed that the mass was a spongiform object with a whirl-like appearance mixed with air and with peripheral calcification.