Assessing Small Bowel Stricturing and Morphology in Crohn's Disease Using Semi-automated Image Analysis

Inflamm Bowel Dis. 2020 Apr 11;26(5):734-742. doi: 10.1093/ibd/izz196.


Background: Evaluating structural damage using imaging is essential for the evaluation of small intestinal Crohn's disease (CD), but it is limited by potential interobserver variation. We compared the agreement of enterography-based bowel damage measurements collected by experienced radiologists and a semi-automated image analysis system.

Methods: Patients with small bowel CD undergoing a CT-enterography (CTE) between 2011 and 2017 in a tertiary care setting were retrospectively reviewed. CT-enterography studies were reviewed by 2 experienced radiologists and separately underwent automated computer image analysis using bowel measurement software. Measurements included maximum bowel wall thickness (BWT-max), maximum bowel dilation (DIL-max), minimum lumen diameter (LUM-min), and the presence of a stricture. Measurement correlation coefficients and paired t tests were used to compare individual operator measurements. Multivariate regression was used to model identification of strictures using semi-automated measures.

Results: In 138 studies, the correlation between radiologists and semi-automated measures were similar for BWT-max (r = 0.724, 0.702), DIL-max (r = 0.812, 0.748), and LUM-min (r = 0.428, 0.381), respectively. Mean absolute measurement difference between semi-automated and radiologist measures were no different from the mean difference between paired radiologists for BWT-max (1.26 mm vs 1.12 mm, P = 0.857), DIL-max (2.78 mm vs 2.67 mm, P = 0.557), and LUM-min (0.54 mm vs 0.41 mm, P = 0.596). Finally, models of radiologist-defined intestinal strictures using automatically acquired measurements had an accuracy of 87.6%.

Conclusion: Structural bowel damage measurements collected by semi-automated approaches are comparable to those of experienced radiologists. Radiomic measures of CD will become an important new data source powering clinical decision-making, patient-phenotyping, and assisting radiologists in reporting objective measures of disease status.

Keywords: CT enterography; MR enterography; computer-aided image analysis; intestinal fibrosis; radiomics; segmentation.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Crohn Disease / complications
  • Crohn Disease / diagnostic imaging*
  • Female
  • Humans
  • Image Processing, Computer-Assisted / statistics & numerical data*
  • Intestinal Obstruction / diagnostic imaging*
  • Intestinal Obstruction / etiology
  • Intestine, Small / diagnostic imaging
  • Male
  • Middle Aged
  • Observer Variation
  • Radiologists / statistics & numerical data
  • Radiometry / methods*
  • Reproducibility of Results
  • Retrospective Studies
  • Tomography, X-Ray Computed / statistics & numerical data*