title: Intra-Abdominal Adhesions Make the Interpretation of Magnetic Resonance Enterography in Crohn's Disease More Difficult.
abstract: OBJECTIVE
  The present study compares preoperative magnetic resonance enterography (MRE) accuracy in diagnosing stenoses, abscesses and fistulas to intraoperative findings in Crohn's disease patients, and determines whether discordance between these methods alter surgical plans.
  
  
  METHODS
  Our study included 55 consecutive patients scheduled for elective surgery due to Crohn's disease in a single institution between January 2011 and May 2015, whose surgical findings were also compared to preoperative MREs. Data were retrospectively analyzed.
  
  
  RESULTS
  Among these 55 patients, we found 80 stenoses, 5 abscesses and 18 fistulas during surgery. The MRE sensitivity, specificity and accuracy, respectively, reached 100, 77.8 and 96.4% for stenoses; 80.0, 90.0 and 89.1% for abscesses; and 77.8, 83.8 and 81.8% for fistulas. The operative plan was modified for 7 patients (12.7%) due to erroneous MRE diagnoses. No patient needed conversion or an unplanned stoma placement due to an incorrect diagnosis using MRE. The MRE diagnosis did not agree with the surgical findings for 36 lesions, 16 of which resulted from adhesions that explained the incorrect MRE diagnoses.
  
  
  CONCLUSIONS
  Hence, while MRE is a useful diagnostic tool preoperatively in Crohn's disease patients, the presence of intra-abdominal adhesions may cause erroneous diagnosis through MRE.
authors.affiliation: Department of Colorectal Surgery, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Gisele
authors.initials: G
authors.lastname: Aaltonen
authors.forename: Ilona
authors.initials: I
authors.lastname: Keränen
authors.forename: Monika
authors.initials: M
authors.lastname: Carpelan-Holmström
authors.forename: Ritja
authors.initials: R
authors.lastname: Savolainen
authors.forename: Riikka
authors.initials: R
authors.lastname: Lindén
authors.forename: Anna
authors.initials: A
authors.lastname: Lepistö
mesh_terms: D000005:Abdomen; D018784:Abdominal Abscess / Q000000981:diagnostic imaging / Q000209:etiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000209:etiology; D003424:Crohn Disease / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007412:Intestinal Fistula / Q000000981:diagnostic imaging* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D057234:Preoperative Period; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D000267:Tissue Adhesions / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D055815:Young Adult