title: Compression of the inferior vena cava in bowel obstruction.
abstract: BACKGROUND
  We investigated whether (a) the inferior vena cava (IVC) is compressed in bowel obstruction and (b) some tracts are more compressed than others.
  
  
  METHODS
  Two groups of abdominal computed tomography (CT) examinations were collected retrospectively. Group O (N = 69) scans were positive for bowel obstruction, group C (N = 50) scans were negative for diseases. IVC anteroposterior and lateral diameters (APD, LAD) were assessed at seven levels.
  
  
  RESULTS
  In group C, IVC section had an elliptic shape (APD/LAD: .76 ± .14), the area of which increased gradually from 1.9 (confluence of the iliac veins) to 3.1 cm²/m² of BSA (confluence of the hepatic veins) with a significant narrowing in the hepatic section. In group O, bowel obstruction caused a compression of IVC (APD/LAD: .54 ± .17). Along its course, IVC section area increased from 1.3 to 2.5 cm²/m². At ROC curve analysis, an APD/LAD ratio lower than 0.63 above the confluence of the iliac veins discriminated between O and C groups with sensitivity of 74% and specificity of 96%.
  
  
  CONCLUSIONS
  Bowel obstruction caused a compression of IVC, which involved its entire course except for the terminal section. APD/LAD ratio may be useful to monitor the degree of compression.
authors.affiliation: Department of Bioimaging and Radiological Sciences, Catholic University of the Sacred Heart, 00168 Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cina
authors.forename: Roberto
authors.initials: R
authors.lastname: Zamparelli
authors.forename: Sara
authors.initials: S
authors.lastname: Venturino
authors.forename: Riccardo
authors.initials: R
authors.lastname: Gargaruti
authors.forename: Vittorio
authors.initials: V
authors.lastname: Semeraro
authors.forename: Franco
authors.initials: F
authors.lastname: Cavaliere
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000473:pathology*