Assessment of Crohn's disease-associated small bowel strictures and fibrosis on cross-sectional imaging: a systematic review

Gut. 2019 Jun;68(6):1115-1126. doi: 10.1136/gutjnl-2018-318081. Epub 2019 Apr 3.


Patients with Crohn's disease commonly develop ileal and less commonly colonic strictures, containing various degrees of inflammation and fibrosis. While predominantly inflammatory strictures may benefit from a medical anti-inflammatory treatment, predominantly fibrotic strictures currently require endoscopic balloon dilation or surgery. Therefore, differentiation of the main components of a stricturing lesion is key for defining the therapeutic management. The role of endoscopy to diagnose the nature of strictures is limited by the superficial inspection of the intestinal mucosa, the lack of depth of mucosal biopsies and by the risk of sampling error due to a heterogeneous distribution of inflammation and fibrosis within a stricturing lesion. These limitations may be in part overcome by cross-sectional imaging techniques such as ultrasound, CT and MRI, allowing for a full thickness evaluation of the bowel wall and associated abnormalities. This systematic literature review provides a comprehensive summary of currently used radiologic definitions of strictures. It discusses, by assessing only manuscripts with histopathology as a gold standard, the accuracy for diagnosis of the respective modalities as well as their capability to characterise strictures in terms of inflammation and fibrosis. Definitions for strictures on cross-sectional imaging are heterogeneous; however, accuracy for stricture diagnosis is very high. Although conventional cross-sectional imaging techniques have been reported to distinguish inflammation from fibrosis and grade their severity, they are not sufficiently accurate for use in routine clinical practice. Finally, we present recent consensus recommendations and highlight experimental techniques that may overcome the limitations of current technologies.

Keywords: Crohn’s disease; fibrosis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Comorbidity
  • Constriction, Pathologic / diagnostic imaging
  • Constriction, Pathologic / epidemiology
  • Constriction, Pathologic / pathology
  • Crohn Disease / diagnostic imaging
  • Crohn Disease / epidemiology*
  • Crohn Disease / pathology
  • Cross-Sectional Studies
  • Elasticity Imaging Techniques / methods
  • Female
  • Fibrosis / diagnostic imaging
  • Fibrosis / epidemiology
  • Humans
  • Incidence
  • Intestinal Obstruction / diagnostic imaging
  • Intestinal Obstruction / epidemiology*
  • Intestinal Obstruction / pathology
  • Intestine, Small / diagnostic imaging
  • Intestine, Small / pathology*
  • Magnetic Resonance Imaging / methods
  • Male
  • Multimodal Imaging / methods*
  • Prognosis
  • Risk Assessment
  • Tomography, X-Ray Computed / methods
  • Ultrasonography, Doppler / methods