title: Dynamic contrast-enhanced MRI of the bowel wall for assessment of disease activity in Crohn's disease.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the role of contrast-enhanced dynamic MRI in predicting the disease activity of Crohn's disease.
  
  
  METHODS
  Forty-eight patients in two hospitals who had clinically suspected exacerbation of Crohn's disease were included in this study. In three levels of thickened small-bowel wall, axial dynamic T1-weighted sequences were performed every 4-6 sec for a total duration of 2-3 min after contrast administration; static T1-weighted turbo spin-echo sequences were acquired both before and after contrast administration. The slope of enhancement, enhancement ratio, time to enhancement, enhancement time, and thickness of the small-bowel wall were determined. These MRI results were compared with overall clinical grade, Crohn's disease activity index (CDAI), and Van Hees activity index. Clinical grade was based on clinical information, physical findings, laboratory studies, endoscopy, surgery, and other imaging studies. Spearman's correlation coefficient and p values were determined per hospital. Fisher's z-transformation was applied before pooling the correlation coefficients from both hospitals.
  
  
  RESULTS
  The enhancement ratio based on the static series showed significant correlation with the clinical grade (r = 0.29, p = 0.045), CDAI (r =0.31, p = 0.033), and Van Hees activity index (r = 0.36, p = 0.016). The enhancement ratio based on the dynamic series correlated significantly with the CDAI (r = 0.38, p = 0.016). Wall thickness correlated significantly with clinical grade (r = 0.47, p = 0.003) and Van Hees activity index (r = 0.41, p = 0.007).
  
  
  CONCLUSIONS
  These data suggest that the enhancement ratio of bowel wall after IV administration of gadodiamide and bowel wall thickness are weak to moderate indicators of the severity of Crohn's disease.
authors.affiliation: Department of Radiology, Academic Medical Center, G1-211, PO Box 22700, Amsterdam 1100 DE, The Netherlands.
authors.forename: Jasper
authors.initials: J
authors.lastname: Florie
authors.forename: Martin N J M
authors.initials: MN
authors.lastname: Wasser
authors.forename: Kasia
authors.initials: K
authors.lastname: Arts-Cieslik
authors.forename: Erik M
authors.initials: EM
authors.lastname: Akkerman
authors.forename: Peter D
authors.initials: PD
authors.lastname: Siersema
authors.forename: Jaap
authors.initials: J
authors.lastname: Stoker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003287:Contrast Media; D003424:Crohn Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media