title: Diffusion-weighted MRI Enables to Accurately Grade Inflammatory Activity in Patients of Ileocolonic Crohn's Disease: Results from an Observational Study.
abstract: Diffusion-weighted imaging (DWI) is a novel technique to evaluate bowel inflammation in Crohn's disease (CD). It remains unclear whether DWI could differentiate grades of inflammation activity and add to the accuracy of conventional magnetic resonance enterography (MRE) in defining disease activity. We aimed to assess the accuracy of DWI for evaluating ileocolonic CD inflammation compared with conventional MRE, using ileocolonoscopy as reference standard.
  
  
  
  This was an observational study of CD patients who underwent both ileocolonoscopy and MRE with DWI. The conventional MRE and DWI findings of the ileocolon were scored from 0 to 3. The respective segment endoscopic disease activity was scored by simplified endoscopic score for Crohn's disease (SES-CD) and was graded as inactive (0-2), mild (3-6) or moderate-severe (≥7).
  
  
  
  One hundred eighty-five bowel segments from 43 consecutive CD patients were evaluated and included inactive (n = 86), mild (n = 72), and moderate-severe (n = 27) ileo-colonic segments. The area under the receiver operating characteristics curve (AUC) of 0.973 for apparent diffusion coefficient (ADC) to differentiate active from inactive CD was significantly higher than those of conventional MRE parameters (AUC between 0.840 and 0.940). Higher accuracy of ADC (AUC = 0.919) for differentiating inactive-mild from moderate-severe CD was also shown compared with that of conventional MRE parameters (AUC between 0.868 and 0.915). ADC values demonstrated strongest correlation with SES-CD (r = -0.880) comparing to DWI SI and conventional MRE parameters (r between 0.787 and 0.867).
  
  
  
  DWI enables to accurately grade inflammatory activity in patients of ileocolonic CD and may be better suited than conventional MRE for monitoring the activity of CD.
authors.affiliation: Departments of *Radiology, and †Gastroenterology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; ‡Department of Biomedical Engineering, Cancer Biology and Radiology, Wake Forest School of Medicine, Winston-Salam, North Carolina; §Clinical Research Center, The ZhongShan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China; and ‖IBD Service, Department of Gastroenterology, Sheba Medical Center, Sackler School of Medicine, Tel-Aviv University, Tel Hashomer, Israel.
authors.forename: Xue-Hua
authors.initials: XH
authors.lastname: Li
authors.forename: Can-Hui
authors.initials: CH
authors.lastname: Sun
authors.forename: Ren
authors.initials: R
authors.lastname: Mao
authors.forename: Si-Yun
authors.initials: SY
authors.lastname: Huang
authors.forename: Zhong-Wei
authors.initials: ZW
authors.lastname: Zhang
authors.forename: Xu-Feng
authors.initials: XF
authors.lastname: Yang
authors.forename: Li
authors.initials: L
authors.lastname: Huang
authors.forename: Jin-Jiang
authors.initials: JJ
authors.lastname: Lin
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Shomron
authors.initials: S
authors.lastname: Ben-Horin
authors.forename: Shi-Ting
authors.initials: ST
authors.lastname: Feng
authors.forename: Min-Hu
authors.initials: MH
authors.lastname: Chen
authors.forename: Zi-Ping
authors.initials: ZP
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D003106:Colon / Q000000981:diagnostic imaging* / Q000473:pathology; D003424:Crohn Disease / Q000000981:diagnostic imaging* / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007082:Ileum / Q000000981:diagnostic imaging* / Q000473:pathology; D007249:Inflammation / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D012372:ROC Curve; D055815:Young Adult