Integrating Intestinal Ultrasound to Clinical Trials in Patients With Crohn's Disease: Opportunities and Challenges

This narrative review summarizes the current knowledge on using intestinal ultrasonography (IUS) to evaluate disease activity in patients with Crohn's disease (CD) and explores its potential role in clinical trials. Current trial endpoints and their limitations are discussed, highlighting the need for more patient-centric approaches, including increased use of magnetic resonance enterography (MRE) and IUS. Intestinal ultrasonography offers several advantages: it is noninvasive, requires no sedation, bowel preparation, or exposure to ionizing radiation, and enables real-time assessment of disease activity. It also demonstrates high sensitivity and specificity for detecting transmural inflammation and complications such as strictures, abscesses, and fistulas. Compared with cross-sectional imaging modalities like MRE and computed tomography, IUS is more patient-friendly, cost-effective, and suitable for point-of-care examination. However, challenges remain, including the lack of a universally accepted disease activity scoring system for MRE or IUS, despite the development and validation of several scoring tools. Key unmet needs include standardization of image acquisition and reporting, adequate training of healthcare professionals, improved access to equipment, and reimbursement pathways. Intestinal ultrasonography is increasingly being integrated into clinical trials to assess transmural inflammatory changes in CD, with IUS-based measures of transmural remission or response showing promise as potential endpoints. Although its advantages are clear, addressing these unmet needs is essential to broaden the adoption of IUS in both clinical trials and routine clinical practice.