Bettenworth D¹, Bokemeyer A¹, Baker M², Mao R^3,4, Parker CE⁵, Nguyen T⁵, Ma C^5,6, Panés J⁷, Rimola J⁸, Fletcher JG⁹, Jairath V^5,10,11, Feagan BG^5,10,11, Rieder F^4,12; Stenosis Therapy and Anti-Fibrotic Research (STAR) Consortium.. Gut. 2019 Apr 3. pii: gutjnl-2018-318081. doi: 10.1136/gutjnl-2018-318081. [Epub ahead of print]

Author information

1 Department of Medicine B, Gastroenterology and Hepatology, University of Münster, Münster, North Rhine-Westphalia, Germany.

2 Section of Abdominal Imaging, Imaging Institute, Digestive Disease Institute and Cancer Institute, Cleveland Clinic, Cleveland, Ohio, USA.

3 Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.

4 Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA.

5 Robarts Clinical Trials, London, Ontario, Canada.

6 Division of Gastroenterology and Hepatology, University of Calgary, Calgary, Alberta, Canada.

7 Department of Gastroenterology, Hospital Clinic de Barcelona, Barcelona, Catalunya, Spain.

8 Department of Radiology, Hospital Clínic de Barcelona, Institut d'investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.

9 Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.

10 Department of Medicine, Western University, London, Ontario, Canada.

11 Department of Biostatistics and Epidemiology, Western University, London, Ontario, Canada.

12 Department of Gastroenterology, Hepatology and Nutrition, Digestive Diseases and Surgery Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA.

Abstract

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.