Accuracy of Diffusion-weighted Magnetic Resonance Imaging in Detecting Mucosal Healing and Treatment Response, and in Predicting Surgery, in Crohn's Disease

J Crohns Colitis. 2018 Nov 9;12(10):1180-1190. doi: 10.1093/ecco-jcc/jjy098.

Abstract

Background and aims: The Nancy score is a luminal Crohn's disease [CD] activity index applied in diffusion-weighted magnetic resonance imaging [DW-MRI]. We assessed the accuracy of the Nancy score in detecting mucosal healing and treatment response, and in predicting surgery.

Methods: This was a retrospective, single-centre study of all patients with active CD and serial DW-MRI before and after treatment initiation with a biologic drug, between January 2010 and September 2016. The gold standard was endoscopy. The association between the Nancy score and the cumulative probability of intestinal resection during follow-up was tested combining Kaplan-Meier curves and log-rank testing.

Results: A total of 96 patients were included; 20 had concomitantly undergone endoscopy. The Nancy score correlated well with the Crohn's Disease Endoscopic Index of Severity [r = 0.60 for the total score and r = 0.63 for the segmental score]. A total Nancy score <6 and a segmental Nancy score <2 detected mucosal healing with an area under the receiver operating characteristic curve [AUROC] of 0.82 (95% confidence interval [CI] 0.69-0.94, p <0.0001) and 0.80 [95% CI 0.73-0.87, p <0.0001], respectively. The Nancy score was highly sensitive to changes [Guyatt's responsiveness indices: 1.18 for the total score and 0.85 for the segmental score]. Mucosal healing on DW-MRI after treatment initiation was associated with a lower cumulative probability of intestinal surgery (p = 0.0251, median [interquartile range: IQR] follow-up 2.2 [1.6-3.7] years).

Conclusions: In CD, the Nancy score accurately detects mucosal healing and treatment response, the latter associated with a lower likelihood of intestinal resection.

MeSH terms

  • Adult
  • Crohn Disease* / diagnosis
  • Crohn Disease* / drug therapy
  • Diffusion Magnetic Resonance Imaging / methods*
  • Diffusion Magnetic Resonance Imaging / statistics & numerical data
  • Dimensional Measurement Accuracy
  • Drug Monitoring / methods
  • Endoscopy, Gastrointestinal / methods
  • Female
  • Gastrointestinal Agents / therapeutic use
  • Humans
  • Immunologic Factors / therapeutic use*
  • Intestinal Mucosa* / diagnostic imaging
  • Intestinal Mucosa* / drug effects
  • Kaplan-Meier Estimate
  • Male
  • Outcome Assessment, Health Care
  • Predictive Value of Tests
  • Retrospective Studies

Substances

  • Gastrointestinal Agents
  • Immunologic Factors