Emerging role of intestinal ultrasound in detecting postoperative recurrence in Crohn's disease

Postoperative recurrence remains a major challenge in Crohn's disease (CD), with ileocolonoscopy still considered the reference standard for detecting recurrence and guiding postoperative management. However, repeated endoscopic assessment is invasive, costly, and poorly tolerated, highlighting the need for reliable non-invasive monitoring strategies. Intestinal ultrasound (IUS) has emerged as a promising complementary tool for postoperative surveillance, allowing real-time evaluation of transmural and extramural inflammation. Recent studies and meta-analyses have demonstrated good diagnostic performance of IUS for detecting postoperative recurrence, with pooled sensitivities and specificities reaching 94% and 84%, respectively, while higher bowel wall thickness thresholds (≥5.5 mm) are strongly associated with severe postoperative recurrence. Current evidence supports the integration of IUS with fecal calprotectin, clinical assessment, and endoscopy within a multimodal and risk-adapted follow-up strategy. In particular, IUS may help identify patients requiring closer surveillance, earlier ileocolonoscopy, therapeutic escalation, or additional cross-sectional imaging. Emerging data also suggest that the timing of postoperative IUS assessment is clinically relevant, as very early examinations may be confounded by postoperative inflammatory and remodeling changes. Nevertheless, important limitations remain. No IUS score has yet been specifically validated for postoperative CD anatomy, standardized postoperative-specific thresholds are lacking, and interpretation may be influenced by surgical configuration and operator expertise. This review summarizes the current evidence regarding the role of IUS in postoperative CD, discussing its diagnostic performance, integration with biomarkers and endoscopy, current limitations, and potential role in personalized postoperative monitoring strategies.