title: Nodules in the thickened greater omentum: a good indicator of lesions?
abstract: OBJECTIVE
  In patients with unclear ascites, a thickened greater omentum with variable nodules is usually encountered with high-frequency insonation. The purpose of our study was to assess the importance of nodules in indicating the origin of ascites.
  
  
  METHODS
  In patients suggested for a biopsy of the greater omentum, if nodules were found in the omentum, sonograms of the nodules were recorded, and during the biopsy, 2 passes were made for each procedure in the nodule and the thickest region without nodules, respectively. A biopsy was considered successful if a specific benign or malignant diagnosis was made.
  
  
  RESULTS
  In the 258 patients undergoing sonographically guided biopsies of the greater omentum from November 2001 to November 2008, the percentage of definitive diagnoses was 94.57% (244 of 258), and sonography showed nodules in 62 patients. Nodules were found more often by a 10-MHz transducer (62 cases) than by a 3.5-MHz transducer (15 cases). The percentage of definitive diagnoses by sonographically guided biopsies was 100% (62 of 62) at the sites of the nodules and decreased to 87.1% (54 of 62) at the sites without nodules. According to the pathologic results, 48 cases were peritoneal carcinomatosis, and 14 cases were tuberculous peritonitis. The sensitivity and specificity of nodules for indicating malignant ascites were 77.42% and 75.27%, respectively.
  
  
  CONCLUSIONS
  Nodules in the greater omentum were good indicators of lesions and were well shown by a high-frequency transducer. A biopsy at the site of a nodule could substantially increase the positive biopsy result rate.
authors.affiliation: Department of Ultrasound, First Affiliated Hospital of China Medical University, 155 N Nanjing Rd, Heping District, 110001 Shenyang, Liaoning, China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Que
authors.forename: Chunmei
authors.initials: C
authors.lastname: Tao
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Xuemei
authors.initials: X
authors.lastname: Wang
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhao
authors.forename: Guocheng
authors.initials: G
authors.lastname: Ou
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000368:Aged; D001201:Ascites / Q000209:etiology*; D001706:Biopsy / Q000379:methods; D002277:Carcinoma / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009852:Omentum / Q000000981:diagnostic imaging* / Q000473:pathology; D010532:Peritoneal Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D012680:Sensitivity and Specificity; D014159:Transducers; D014376:Tuberculosis / Q000473:pathology; D018084:Ultrasonography, Interventional / Q000295:instrumentation