Large cholesterol polyps of the gallbladder: diagnosis by means of US and endoscopic US.

Abstract

PURPOSE: To identify ultrasonographic (US) features of large cholesterol polyps (> 10 mm in diameter) of the gallbladder in the differential diagnosis of polypoid lesions. MATERIALS AND METHODS: Sixty-seven patients underwent US (n = 67) and endoscopic US (n = 33). Fourteen patients had large cholesterol polyps. Findings in these patients were compared with those in patients with small cholesterol polyps (< or = 10 mm in diameter; n = 34) or other polypoid lesions (n = 19). RESULTS: US demonstrated the large cholesterol polyps as pedunculated masses with granular surfaces. In 94% of patients, all small cholesterol polyps were echogenic whereas the large cholesterol polyps tended to have decreased echogenicity. Endoscopic US showed complete or partial aggregation of echogenic spots in all cholesterol polyps-but not in other polypoid lesions, which included carcinomas. CONCLUSION: Aggregation of echogenic spots seems to be a US feature characteristic of both large and small cholesterol polyps. Routine use of endoscopic US is recommended for differential diagnosis of polypoid lesions because of its high resolution.