Lancet Gastroenterol Hepatol. 2024 Dec;9(12):1101-1110.doi: 10.1016/S2468-1253(24)00265-6. Epub 2024 Oct 22.

Cathy Lu ¹, Ryan Rosentreter ², Claire E Parker ³, Julie Remillard ³, Stephanie R Wilson ⁴, Mark E Baker ⁵, Gauraang Bhatnagar ⁶, Jakob Begun ⁷, David H Bruining ⁸, Robert V Bryant ⁷, Britt Christensen ⁹, Brian G Feagan ¹⁰, Joel G Fletcher ¹¹, Ilyssa Gordon ¹², Gaylyn Henderson ¹³, Vipul Jairath ¹⁴, John Knudsen ¹¹, Torsten Kucharzik ¹⁵, Kyle Lesack ², Christian Maaser ¹⁶, Giovanni Maconi ¹⁷, Kerri Novak ², Jordi Rimola ¹⁸, Stuart A Taylor ¹⁹, Rune Wilkens ²⁰, Florian Rieder ²¹; Stenosis Therapy and Anti-Fibrotic Research (STAR) consortium

Author information

¹Division of Gastroenterology and Hepatology, Department of Medicine, University of Calgary, Calgary, AB, Canada. Electronic address: luc@ucalgary.ca.

²Division of Gastroenterology and Hepatology, Department of Medicine, University of Calgary, Calgary, AB, Canada.

³Alimentiv, London, ON, Canada.

⁴Division of Gastroenterology and Hepatology, Department of Medicine, University of Calgary, Calgary, AB, Canada; Department of Radiology, University of Calgary, Calgary, AB, Canada.

⁵Imaging Institute, Cleveland Clinic, Cleveland, OH, USA.

⁶Centre for Medical Imaging, University College London, London, UK; Frimley Health NHS Foundation Trust, Surrey, UK.

⁷Mater Research Institute, University of Queensland-Translational Research Institute, Brisbane, QLD, Australia; Department of Gastroenterology, The Queen Elizabeth Hospital, Adelaide, SA, Australia.

⁸Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.

⁹Department of Gastroenterology, Royal Melbourne Hospital and University of Melbourne, Melbourne, VIC, Australia.

¹⁰Alimentiv, London, ON, Canada; Department of Medicine, Western University, London, ON, Canada.

¹¹Department of Radiology, Mayo Clinic, Rochester, MN, USA.

¹²Department of Pathology, Robert J Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.

¹³Gutless and Glamourous, Atlanta, GA, USA.

¹⁴Alimentiv, London, ON, Canada; Department of Medicine, Western University, London, ON, Canada; Department of Epidemiology and Biostatistics, Department of Medicine, Western University, London, ON, Canada.

¹⁵Department of General Internal Medicine and Gastroenterology, University Teaching Hospital Lüneburg, Lüneberg, Germany.

¹⁶Outpatients' Department of Gastroenterology, University Teaching Hospital Lüneburg, Lüneberg, Germany.

¹⁷Gastroenterology Unit, Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy.

¹⁸IBD unit, Radiology Department, Hospital Clinic Barcelona, IDIBAPS, Barcelona, Spain.

¹⁹Centre for Medical Imaging, University College London, London, UK.

²⁰Copenhagen University Hospital-Bispebjerg, Digestive Disease Center, Copenhagen, Denmark; Copenhagen Intestinal Ultrasound, Bispebjerg Hospital, Copenhagen, Denmark.

²¹Program for Global Translational Inflammatory Bowel Disease, Cleveland Clinic, Cleveland, OH, USA; Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Gastroenterology, Hepatology and Nutrition, Digestive Disease Institute, Cleveland Clinic, Cleveland, Ohio, USA.

Abstract

Background: Diagnostic imaging using CT enterography, magnetic resonance enterography, and intestinal ultrasound are important tools in evaluating stricturing Crohn's disease. Definitions of strictures have been developed for CT enterography and magnetic resonance enterography. However, expert recommendations for definitions and treatment response of strictures on intestinal ultrasound are not available. The aim of this study was to standardise definitions, diagnosis, and treatment response criteria in small bowel stricturing Crohn's disease on intestinal ultrasound.

Methods: Using modified RAND-University of California Los Angeles Appropriateness Method, a diverse expert panel of 13 gastroenterologists, seven radiologists, and two patient representatives was assembled. A total of 466 statements on definitions and response to therapy of stricturing Crohn's disease on intestinal ultrasound were generated from a systematic review and from expert opinion, with subsequent rating for appropriateness. Two rounds of voting with an interposed survey result discussion were performed. Statements were classified as inappropriate, uncertain, or appropriate based on the median panel rating and degree of disagreement. Appropriateness was rated using a nine-point Likert scale (1 being inappropriate, 9 being highly appropriate).

Findings: A naive or anastomotic small bowel Crohn's disease stricture on intestinal ultrasound is defined by the combination of bowel wall thickening, luminal narrowing, and pre-stenotic dilation. Bowel wall thickness is defined as being more than 3 mm. Luminal narrowing is defined as either a luminal diameter reduction of more than 50% in the narrowest area and relative to a normal adjacent bowel loop, or a luminal diameter of less than 1 cm. Pre-stenotic dilation is defined as more than 2·5 cm or an increase in bowel diameter relative to a normal adjacent bowel loop. Definitions for grading hyperaemia, inflammatory fat, wall stratification, intestinal ultrasound machine technical parameters, and image acquisition were also devised. Treatment response of strictures was defined as reduction in stricture length, bowel wall thickening, luminal narrowing, pre-stenotic dilation, and motility abnormalities.

Interpretation: To our knowledge, this is the first intestinal ultrasound appropriateness rating exercise conducted for defining, diagnosing, and measuring response to therapy in small bowel stricturing Crohn's disease and informs future clinical use and intestinal ultrasound index development for clinical trials.

Funding: Leona M and Harry B Helmsley Charitable Trust.