IUS For Detecting Postoperative Crohn's Disease Recurrence: The Lancet Gastroenterology & Hepatology | July 2026

Introduction:

Endoscopic assessment remains the standard for detecting postoperative recurrence after ileocolic resection in Crohn's disease, but it is invasive and resource-intensive. This international multidisciplinary RAND/UCLA consensus developed standardised recommendations for the use of intestinal ultrasound (IUS) in postoperative surveillance.

Why was this guideline needed?

• Endoscopy remains invasive and is not always well accepted by patients.
• Intestinal ultrasound is a non-invasive, radiation-free bedside imaging tool with increasing clinical use.
• There has been no international consensus on postoperative IUS assessment in Crohn's disease.
• Standardised examination protocols are required for clinical practice and research.
• Uniform reporting will improve patient care and future clinical trials.

Key Takeaways:

• Intestinal ultrasound is considered an appropriate non-invasive modality for postoperative surveillance following ileocolic resection in Crohn's disease.
• The recommended examination should systematically assess the neoterminal ileum, neoterminal ileal inlet, ileal and colonic sides of the anastomosis, adjacent colonic segments, and surrounding mesentery.
• Key sonographic parameters include bowel wall thickness, bowel wall stratification, bowel wall vascularity, mesenteric inflammatory fat, lymphadenopathy, luminal narrowing, strictures (including length), prestenotic dilatation, abscesses, fistulas, inflammatory masses, and sinus tracts.
• The neoterminal ileum and ileal inlet are the most important sites for detecting clinically meaningful postoperative recurrence.
• Intestinal ultrasound should not be performed within the first four weeks after surgery to avoid misinterpretation related to postoperative healing.
• The first routine postoperative ultrasound is recommended between 3 and 12 months after surgery, depending on the patient's clinical risk profile and management strategy.

Clinical Impact:

These expert recommendations establish a standardized framework for incorporating intestinal ultrasound into postoperative Crohn's disease surveillance. Wider adoption of IUS could reduce dependence on routine endoscopy, improve patient comfort, facilitate earlier detection of recurrence, and provide a consistent imaging approach for future clinical trials.

Bottom Line:

Intestinal ultrasound is now recommended as a standardized, non-invasive tool for monitoring postoperative recurrence in Crohn's disease. Careful evaluation of the neoterminal ileum and anastomosis, combined with comprehensive assessment of inflammatory and structural changes, should become part of routine postoperative surveillance, with the first examination performed 3–12 months after surgery.