Gossypiboma of the Leg: MR Imaging Characteristics. A Case Report

Characteristics. A Case ReportWe report a 22-year-old man with a solid mass in the right proximal leg, which was furned out to be a gossypiboma.MR imaging revealed a well-defined mass lesion that showed intermediate signal intensity at T1-weighted imaging (T1WI) and slightly high signal intensity at T2-weighted imaging (T2WI).Wavy, low-signal-intensity stripes were visible within the fluid-filled central cavity.At surgical exploration, a sponge, retained after previous knee surgery, was discovered, and it was found that a granuloma had developed.Pathologic examination revealed granulomatous inflammation, with lymphocyte and giant cell infiltration.The presence of wavy, low-signal-intensity gauze fibers at T2WI may be a characteristic MR appearance of gossypiboma.ossypiboma is a rare tumor caused by gauze fibers retained during surgery.It often mimics other neoplasms and may cause diagnostic difficulty and serious complications (1 3).For a soft-tissue tumor, MRI, as used in this case, is usually the imaging modality of choice.To our knowledge, a gossypiboma of the extremities has not been previously reported in the literature in English (1 6); we describe the MR imaging findings of a gossypiboma of the leg, detailing its pathologic correlation. CASE REPORTA 22-year-old man presented with a painful mass in the right proximal leg, explaining that during the previous year, progressive enlargement had occurred.Five years earlier, he had been involved in a traffic accident, resulting in avulsion fracture of the right anterior cruciate ligament.Treatment at a local clinic involved pull-out suturing and internal fixation with screws, and the screws were removed one year later.Physical examination revealed a solid mass about 7 5 3 cm in size, and anterolaterally, there was mild tenderness of the right proximal leg.The findings of laboratory examinations were unremarkable, with a normal cell count and normal biochemistry.Conventional radiography of the right knee showed that laterally, the soft-tissue density of the proximal leg had increased, that bony structures were intact, and there was no abnormal calcification.Because the mass was thought to be a soft-tissue tumor, MRI was performed; spin-echo T1-weighted (TR/TE: 419/17.8)and fast spin-echo T2weighted (TR/TE: 1876/90) images revealed an elliptical, well-circumscribed mass in the anterolateral aspect of the right proximal leg, abutting the crural fascia (Figs.1A, B).Compared to skeletal muscle, its signal intensity was intermediate at T1WI and slightly high at T2WI; additionally, a central fusiform region showed low signal intensity at T1WI and high signal intensity at T2WI, and this was thought to indicate fluid