title: Demographics and frequency of the intermittently upturned omentum at CT.
abstract: OBJECTIVE
  To describe the demographics and frequency of the intermittently upturned omentum at CT.
  
  
  METHODS
  We retrospectively reviewed abdominal CT scans of 336 consecutive patients (189 men and 147 women) who were imaged between June 1 and June 17, 2010 and who had prior comparison scans. Readers recorded the presence or absence of an intermittently upturned omentum, defined as a thick rind of fat interposed between the liver and the anterior abdominal wall seen on one but not the other scan. At chart review, we recorded patient demographics and other clinical characteristics (prior surgical history, presence of cirrhosis).
  
  
  RESULTS
  An intermittently upturned omentum was found in 10 of 336 (3.0%) patients. An intermittently upturned omentum was seen more commonly in men than in women (9 of 189 men, or 4.8% versus 1 of 147 women, or 0.7%, p=0.047) and in cirrhotics (4 of 37 cirrhotics, or 10.8% versus 6 of 299 non-cirrhotics, or 2.0%, p=0.023). In a sub-analysis of patients without prior abdominal surgery, this finding was again seen more commonly in men than women (7 of 163 men, or 4.3% versus 0 of 134 women, or 0%, p=0.018) and in cirrhotics (3 of 33 cirrhotics, or 9.1% versus 4 of 264 non-cirrhotics, or 1.5%, p=0.032).
  
  
  CONCLUSIONS
  An intermittently upturned omentum is not uncommon and is more frequently seen in men and in patients with cirrhosis who may have a larger anterior hepatic space.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California, San Francisco, Department of Radiology (AP, WW, ZJW, JY, EMW, BMY), University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628, United States.
authors.forename: Alex
authors.initials: A
authors.lastname: Penn
authors.forename: Wilbur
authors.initials: W
authors.lastname: Wang
authors.forename: Zhen Jane
authors.initials: ZJ
authors.lastname: Wang
authors.forename: Judy
authors.initials: J
authors.lastname: Yee
authors.forename: Emily M
authors.initials: EM
authors.lastname: Webb
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Yeh
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009852:Omentum / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D010532:Peritoneal Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015203:Reproducibility of Results; D012307:Risk Factors; D012495:San Francisco / Q000453:epidemiology; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D014102:Torsion Abnormality / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D055815:Young Adult
keywords: CT; Cirrhosis; Greater omentum; Omental torsion; Upturned omentum