Multimodality ultrasound in Crohn's disease strictures

Area of Science:

• Gastroenterology
• Medical Imaging
• Radiology

Background:

• Crohn's disease (CD) strictures present a diagnostic challenge, necessitating differentiation between inflammatory and fibrotic components for optimal treatment.
• Accurate characterization of CD strictures is crucial for guiding therapeutic strategies and improving patient outcomes.

Purpose of the Study:

• To assess the utility of multimodal intestinal ultrasound techniques in detecting and characterizing small bowel strictures associated with Crohn's disease.
• Evaluate the combined diagnostic performance of small intestine contrast ultrasonography (SICUS), contrast-enhanced ultrasound (CEUS), and ultrasound elastography for CD strictures.

Main Methods:

• A systematic review adhering to PRISMA guidelines was performed, searching PubMed and EMBASE databases.
• Included 43 studies comparing SICUS, CEUS, and elastography against cross-sectional imaging, histopathology, endoscopy, or surgical findings for CD stricture assessment.

Main Results:

• SICUS demonstrated high sensitivity (88%-98%) for stricture detection, with specific criteria like wall thickness >3mm.
• CEUS and elastography (particularly shear wave elastography) effectively differentiated fibrotic from inflammatory strictures using quantitative metrics (e.g., peak enhancement, AUC, shear wave speed).
• Shear wave elastography showed high diagnostic accuracy (AUCs 0.88-0.91) for fibrosis detection.

Conclusions:

• Multimodal intestinal ultrasound offers a radiation-free, comprehensive approach for detecting, localizing, and phenotyping CD strictures.
• While promising, standardization of acquisition protocols, predefined cut-offs, and multicenter validation are needed for widespread clinical adoption.