title: Magnetic resonance colonography without bowel cleansing: a prospective cross sectional study in a screening population.
abstract: OBJECTIVE
  To evaluate the diagnostic accuracy of magnetic resonance colonography (MRC) without bowel cleansing in a screening population and compare the results to colonoscopy as a standard of reference.
  
  
  METHODS
  315 screening patients, older than 50 years with a normal risk profile for colorectal cancer, were included in this study. For MRC, a tagging agent (5.0% Gastrografin, 1.0% barium sulphate, 0.2% locust bean gum) was ingested with each main meal within 2 days prior to MRC. No bowel cleansing was applied. For the magnetic resonance examination, a rectal water enema was administered. Data collection was based on contrast enhanced T1 weighted images and TrueFISP images. Magnetic resonance data were analysed for image quality and the presence of colorectal lesions. Conventional colonoscopy and histopathological samples served as reference.
  
  
  RESULTS
  In 4% of all colonic segments, magnetic resonance image quality was insufficient because of untagged faecal material. Adenomatous polyps >5 mm were detected by means of MRC, with a sensitivity of 83.0%. Overall specificity was 90.2% (false positive findings in 19 patients). However, only 16 of 153 lesions <5 mm and 9 of 127 hyperplastic polyps could be visualised on magnetic resonance images.
  
  
  CONCLUSIONS
  Faecal tagging MRC is applicable for screening purposes. It provides good accuracy for the detection of relevant (ie, adenomatous) colorectal lesions >5 mm in a screening population. However, refinements to optimise image quality of faecal tagging are needed.
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Hufelandstrasse 55, D-45122 Essen, Germany. christiane.kuehle@uni-due.de
authors.forename: Christiane A
authors.initials: CA
authors.lastname: Kuehle
authors.forename: Jost
authors.initials: J
authors.lastname: Langhorst
authors.forename: Susanne C
authors.initials: SC
authors.lastname: Ladd
authors.forename: Thomas
authors.initials: T
authors.lastname: Zoepf
authors.forename: Michael
authors.initials: M
authors.lastname: Nuefer
authors.forename: Florian
authors.initials: F
authors.lastname: Grabellus
authors.forename: Joerg
authors.initials: J
authors.lastname: Barkhausen
authors.forename: Guido
authors.initials: G
authors.lastname: Gerken
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Lauenstein
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D003430:Cross-Sectional Studies; D003974:Diatrizoate Meglumine; D005243:Feces; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000175:diagnosis / Q000473:pathology; D044483:Intestinal Polyposis / Q000175:diagnosis / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D011446:Prospective Studies; D012015:Reference Standards; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D003974:Diatrizoate Meglumine