title: Frequency and nature of incidental extra-enteric lesions found on magnetic resonance enterography (MR-E) in patients with inflammatory bowel diseases (IBD).
abstract: BACKGROUND
  The aim of this study was to determine the occurrence of extra-enteric findings in a large cohort of patients undergoing magnetic resonance enterography (MR-E) and to classify the clinical significance of these findings.
  
  
  METHODS
  We retrospectively analyzed 1154 MR-E performed in 1006 patients referred to our radiological department between 1999-2005. The reasons for referral were suspected or proven inflammatory bowel diseases (IBD) (n = 710), further diagnostic work-up for small bowel disease because of non-specific abdominal symptoms (SBD; n = 182) or suspected small bowel malignancies (SBM; n = 114). All extra-enteric findings were reviewed by a radiologist and a gastroenterologist and were classified as having high, moderate, or low significance for further diagnostic or therapeutic procedures.
  
  
  RESULTS
  The average age of all patients was 40+/-16 (Mean+/-SD) years (y) (IBD 35+/-13 y; SBD 49+/-16 y; SBM 57+/-15 y). A total of 1113 extra-enteric findings were detected in 600 of 1006 patients (59.6%). Of these findings 180 (16.2%) were judged as having a high, 212 (19.0%) a moderate and 721 (64.8%) a low significance. On a per group basis in patients with IBD 12.0% of the findings were of major clinical significance compared to 13.7% and 33.3% in patients with SBD and SBM, respectively. The most common major findings were abscesses (69.9%) in the IBD group and extraintestinal tumors, metastases or masses in the SBD and SBM groups (41.9% and 74.2%, respectively).
  
  
  CONCLUSIONS
  MR-E reveals a substantial number of extra-enteric findings, supporting the role of a cross-sectional imaging method for the evaluation of the small bowel.
authors.affiliation: Department of Internal Medicine, University of Regensburg, Regensburg, Germany. hherf@med.unc.edu
authors.forename: Hans H
authors.initials: HH
authors.lastname: Herfarth
authors.forename: Michael
authors.initials: M
authors.lastname: Grunert
authors.forename: Frank
authors.initials: F
authors.lastname: Klebl
authors.forename: Ulrike
authors.initials: U
authors.lastname: Strauch
authors.forename: Stefan
authors.initials: S
authors.lastname: Feuerbach
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schölmerich
authors.forename: Gerhard
authors.initials: G
authors.lastname: Rogler
authors.forename: Andreas G
authors.initials: AG
authors.lastname: Schreyer