Transabdominal intestinal ultrasound (IUS) is gaining acceptance as a point-of-care test to objectively assess disease activity in Crohn's disease (CD).

In order to incorporate individual parameters in a future definition of transmural healing, and for the consistent application of IUS as a modality to assess treatment outcomes and establish therapeutic targets to ensure comparability between future studies, the inter-observer agreement should be determined for all relevant parameters.

Inclusion Criteria:

• Crohn's disease evolving for at least 1 months
• Patient older than 18 years
• Patient covered by French national health insurance
• Written informed consent

Exclusion Criteria:

• Pregnant women or breastfeeding
• Minor
• Patient deprived of liberty by administrative or judicial decision or placed under judicial protection (guardianship or supervision)