title: Abdominal and pelvic CT: is positive enteric contrast still necessary? Results of a retrospective observational study.
abstract: OBJECTIVE
  Evaluation of diagnostic accuracy of abdominal CT depending on the type of enteric contrast agent.
  
  
  METHODS
  Multislice CTs of 2,008 patients with different types of oral preparation (positive with barium, n = 576; neutral with water, n = 716; and no enteric contrast, n = 716) were retrospectively evaluated by two radiologists including delineation of intestinal segments and influence on diagnosis and diagnostic reliability exerted by the enteric contrast, using a three-point scale. Furthermore, diagnostic reliability of the delineation of selected enteric pathologies was noted. CT data were assigned into groups: oncology, inflammation, vascular, pathology, trauma and gastrointestinal pathology.
  
  
  RESULTS
  Delineation of the bowel was clearly practicable across all segments irrespective of the type of enteric contrast, though a slight impairment was observed without enteric contrast. Although delineation of intestinal pathologies was mostly classified "clearly delimitable" more difficulties occurred without oral contrast (neutral/positive/no contrast, 0.8 %/3.8 %/6.5 %). Compared to examinations without enteric contrast, there was a significant improvement in diagnosis that was even increased regarding the reader's diagnostic reliability. Positive opacification impaired detection of mucosal enhancement or intestinal bleeding.
  
  
  CONCLUSIONS
  Water can replace positive enteric contrast agents in abdominal CTs. However, selected clinical questions require individual enteric contrast preparations. Pathology detection is noticeably impaired without any enteric contrast.
authors.affiliation: Department of Clinical Radiology, University Hospital Münster, Münster, Germany, sara.kammerer@ukmuenster.de.
authors.forename: S
authors.initials: S
authors.lastname: Kammerer
authors.forename: A J
authors.initials: AJ
authors.lastname: Höink
authors.forename: J
authors.initials: J
authors.lastname: Wessling
authors.forename: H
authors.initials: H
authors.lastname: Heinzow
authors.forename: R
authors.initials: R
authors.lastname: Koch
authors.forename: C
authors.initials: C
authors.lastname: Schuelke
authors.forename: W
authors.initials: W
authors.lastname: Heindel
authors.forename: B
authors.initials: B
authors.lastname: Buerke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001464:Barium; D003287:Contrast Media; D005260:Female; D006801:Humans; D007422:Intestines / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000000981:diagnostic imaging*; D011860:Radiography, Abdominal / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D003287:Contrast Media; D001464:Barium