Sonographic appearance of oxidized cellulose (Surgicel): pitfall in the diagnosis of postoperative abscess.

Oxidized regenerated cellulose (Surgicel) is used for intraoperative hemostasis and frequently is left in the surgical bed. We describe the sonographic appearance of Surgicel, which may mimic an abscess in the postoperative setting. Sonograms from six postoperative patients with retained Surgicel were collected. The use of Surgicel was confirmed by consultation with the operating surgeon. In five patients, correlative CT scans were performed. All cases appeared as echogenic masses with posterior reverberation artifact suggestive of an abscess due to gas forming organisms. In three patients, fluid surrounded the echogenic masses. Correlative CT scans showed that the Surgicel masses contained complex collections of fluid and gas. Five of six patients showed no clinical evidence of an abscess. The presence of echogenic masses with posterior reverberation artifact in postoperative patients should alert the sonologist that Surgicel may have been used, and an appropriate history should be sought.