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., Competing Interests: Declaration of interests CL has received speaker fees from AbbVie, Celltrion, Janssen, and Fresenius Kabi, and advisory board fees from AbbVie, Janssen, Lilly, Pfizer, Takeda, Fresenius Kabi, Pendopharm, and Ferring. CEP is an employee of Alimentiv. JR is an employee of Alimentiv. SRW has received partial research support from Samsung for an unrelated project, and equipment support from Samsung, Siemens, and Philips. MEB receives grant support to his institution from Siemens Healthineers, the Leona M and Harry B Helmsley Charitable Trust, and Pfizer, and provides informal consulting to Agomab. JB has received speaker and advisory board fees from Abbvie. DHB has received advisory board fees from Janssen. RVB has received speaker and advisory board fees from AbbVie, BiomeBank, Ferring, Janssen, Shire, and Takeda, and is a shareholder in BiomeBank. BC has received research support and speaker fees from AbbVie, Janssen, Takeda, Celltrion, Sandoz, and Falk. BGF has received speaker and advisory board fees from AbbVie, AbolerIS, AgomAB Therapeutics, Allianthera, Amgen, AnaptysBio, Applied Molecular Transport, Arena Pharma, Avoro Capital Advisors, Atomwise, BioJamp, Biora Therapeutics, Boehringer-Ingelheim, Boxer, Celsius Therapeutics, Celgene or Bristol Myers Squibb, Connect BioPharma, Cytoki, Disc Medicine, Duality, EcoR1, Eli Lilly, Equillium, Ermium, First Wave, First Word Group, Galapagos, Galen Atlantica, Genentech or Roche, Gilead, Gossamer Pharma, GSK, Hinge Bio, Hot Spot Therapeutics, Index Pharma, Imhotex, Immunic Therapeutics, JAK Academy, Janssen, Japan Tobacco, Kaleido Biosciences, Landos Biopharma, Leadiant, LEK Consulting, Lenczner Slaght, LifeSci Capital, Lument AB, Millennium, MiroBio, Morgan Lewis, Morphic Therapeutics, Mylan, OM Pharma, Origo BioPharma, Orphagen, Pandion Therapeutics, Pendopharm, Pfizer, Prometheus Therapeutics and Diagnostics, Play to Know AG, Progenity, Protagonist, PTM Therapeutics, Q32 Bio, Rebiotix, REDX, Roche, Sandoz, Sanofi, Seres Therapeutics, Silverback Therapeutics, Surrozen, Takeda, Teva, Thelium, Tigenix, Tillotts, Ventyx Biosciences, VHSquared, Viatris, Ysios, Ysopia, and Zealand Pharma, and is a shareholder in Gossamer Bio. JGF has received grant support from Siemens Healthineers. VJ has received speaker and advisory board fees from AbbVie, Alimentiv, Arena pharmaceuticals, Asahi Kasei Pharma, Asieris, Astra Zeneca, Avoro Capital, Boehringer Ingelheim, Bristol Myers Squibb, Celltrion, Eli Lilly, Endpoint Health, Ferring, Flagship Pioneering, Fresenius Kabi, Galapagos, Gilde Healthcare, GlaxoSmithKline, Genentech, Gilead Sciences, Innomar, JAMP Pharma, Janssen, Merck, Metacrine, Mylan, Pandion, Pendopharm, Pfizer, Protagonist, Prometheus Biosciences, Reistone Biopharma, Roche, Sandoz, SCOPE, Second Genome, Sorriso pharmaceuticals, Takeda, Teva, Tigenix, Topivert, Ventyx, and Vividion, and research support from Abbvie, Boehringer Ingelheim, Celgene/BMS, Eli Lilly, Gilead Sciences, Janssen, Pfizer, and Tigenix. TK has received advisory board and speaker fees from AbbVie, Amgen, Boehringer Ingelheim, Biogen, Celltrion, Celgene, Bristol-Myers Squibb, Hospira, Mundipharma, Dr Falk Pharma GmbH, Ferring Arzneimittel GmbH, Galapagos, Gilead, Janssen, Merck Sharp & Dohme GmbH, Novartis, Pfizer, Roche, Takeda Pharma GmbH, and UCB Pharma. CM has received speaker or honoraria fees AbbVie, Astra Zeneca, Biogen, Bristol-Myers Squibb, Dr Falk Pharma GmbH, Ferring Arzneimittel, Galapagos, Gilead, Janssen, Lilly, Merck Sharp & Dohme, Pfizer, Roche, Samsung, Takeda Pharma, and Vifor Pharma. GM has received speaker and advisory board fees from Alfa Sigma, Fresenius Kabi, and Gilead. KN has received speaker and advisory board fees from AbbVie, Amgen, Bristol Myers Squibb, Janssen, Lily, Organon, Pendopharm, Pfizer, Ferring, Takeda, and Fresenius Kabi, research support from Pfizer and Janssen, and equipment support from Samsung. JR has received speaker and advisory board fees from Alimentiv, Boehringer Ingelheim, Gilead, Janssen Pharmaceuticals, Takeda, TiGenix, Ferring, and Origo, and research support from AbbVie and Genentech. SAT has received speaker and advisory board fees from Alimentiv and AstraZeneca, and is a shareholder in Motilent. RW has received speaker and advisory board fees from AbbVie, Alimentiv, Janssen, Pfizer, and Takeda. FR is consultant to Adiso, Adnovate, Agomab, Allergan, AbbVie, Arena, Astra Zeneca, Boehringer-Ingelheim, Celgene/BMS, Celltrion, Clinical Data Interchange Standards Consortium, Celsius, Cowen, Ferring, Galapagos, Galmed, Genentech, Gilead, Gossamer, Granite, Guidepoint, Helmsley, Horizon Therapeutics, Image Analysis, Index Pharma, Landos, Jannsen, Koutif, Mestag, Metacrine, Mopac, Morphic, Organovo, Origo, Palisade, Pfizer, Pliant, Prometheus Biosciences, Receptos, RedX, Roche, Samsung, Sanofi, Surmodics, Surrozen, Takeda, Techlab, Teva, Theravance, Thetis, UCB, Ysios, and 89Bio. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)