title: Dark lumen MR colonography based on fecal tagging for detection of colorectal masses: accuracy and patient acceptance.
abstract: BACKGROUND
  Magnetic resonance colonography (MRC) with fecal tagging has recently been investigated in clinical studies for the detection of polyps. We assessed fecal tagging MRC in a field trial.
  
  
  METHODS
  Forty-two patients in a private gastroenterologic practice underwent MRC with barium-based fecal tagging (150 mL of 100% barium at each of 6 main meals before MRC) and conventional colonoscopy. Diagnostic accuracy of MRC and patient acceptance were assessed and compared with the respective results of conventional colonoscopy.
  
  
  RESULTS
  Eighteen percent of all MRC examinations showed a remaining high stool signal in the colon that impeded a reliable inclusion or exclusion of polyps. On a lesion-by-lesion basis, sensitivities for polyp detection were 100% for polyps larger than 2 cm (n = 1), 40% for polyps between 10 and 19 mm, 16.7% for polyps between 6 and 9 mm, and 9.1% for polyps smaller than 6 mm. The main reason for the low acceptance of MRC was the barium preparation, which was rated worse than the bowel cleaning procedure with conventional colonoscopy.
  
  
  CONCLUSIONS
  MRC with fecal tagging must be further optimized. The large amount of barium resulted in poor patient acceptance, and barium according to this protocol did not provide sufficient stool darkening. Other strategies, such as increasing the hydration of stool, must be developed.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Essen, Hufelandstrasse 55, Essen 45122, Germany. susanne.goehde@uni-essen.de
authors.forename: S C
authors.initials: SC
authors.lastname: Goehde
authors.forename: E
authors.initials: E
authors.lastname: Descher
authors.forename: A
authors.initials: A
authors.lastname: Boekstegers
authors.forename: T
authors.initials: T
authors.lastname: Lauenstein
authors.forename: C
authors.initials: C
authors.lastname: Kühle
authors.forename: S G
authors.initials: SG
authors.lastname: Ruehm
authors.forename: W
authors.initials: W
authors.lastname: Ajaj
mesh_terms: D000328:Adult; D000368:Aged; D001466:Barium Sulfate; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003287:Contrast Media; D005243:Feces; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care; D010865:Pilot Projects; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014741:Video Recording
chemical_list: D003287:Contrast Media; D001466:Barium Sulfate