Measurement of the stiffness of the normal terminal ileum mesentery using shear-wave elastography

Real-time shear wave elastography in measuring normal ileocolon intestinal wall stiffness using colonoscopy as reference: A single-center research

Purpose

To investigate the feasibility of real-time shear wave elastography (SWE) in evaluating intestinal wall stiffness, and to establish the threshold SWE value of normal intestinal wall and explore the influencing factors of intestinal SWE.

Method

659 subjects who underwent intestinal SWE and colonoscopy were retrospectively enrolled. The wall elasticity of colonoscopy-confirmed normal/abnormal intestinal segment was measured by transabdominal SWE. Measurement reliability was evaluated by the intraclass correlation coefficient (ICC). The threshold value of SWE in differentiating normal and abnormal intestine was determined using ROC curve analysis with the largest Youden index, and the diagnostic performance of this threshold was evaluated. We explored the effects of gender, age, depth and type of the targeted intestinal segment on the intestinal wall elasticity by t test and logistic linear regression analysis.

Results

The technical success rate of SWE examination is 95.3 % (628/659). The mean SWE value of normal intestinal walls is (5.45 ± 1.34) kPa, which was significantly lower than that of abnormal ones (15.38 kPa±7.22, P < 0.001). Using 8.1 kPa as the threshold， the sensitivity and specificity were 93.5 % and 96.0 % with an AUC of 94.8 %. The overall ICC for SWE measurements was 0.933. Gender (ß=0.278, P = 0.013), depth (ß=0.220, P = 0.043) and type of the targeted segment (ß=0.522, P < 0.001) was associated with the SWE value of intestinal wall, but age was not (ß=0.050, P = 0.484).

Conclusions

SWE is feasible in evaluating the stiffness of intestinal wall with high reliability. The SWE threshold value differentiating normal intestinal wall and abnormal intestinal wall is 8.1 kPa.

Advancements and Challenges in Modeling Mechanobiology in Intestinal Host-Microbiota Interaction

The gastrointestinal tract is a dynamic biomechanical environment where physical forces, cellular processes, and microbial interactions converge to shape the gut health and disease. In this review, we examine the unique mechanical properties of the gut, including peristalsis, viscoelasticity, shear stress, and tissue stiffness, and their roles in modulating host mechanosignaling and microbial behavior under physiological and pathological conditions. We discuss how these mechanical forces regulate gut epithelial integrity, immune responses, and microbial colonization, leading to distinct ecological niches across different intestinal segments. Furthermore, we highlight recent advancements in 3D culture systems and gut-on-a-chip models that accurately recapitulate the complex interplay between biomechanics and gut microbiota. By elucidating the intricate relationship between mechanobiology and gut function, this review underscores the potential for mechanotherapeutic strategies to modulate host-microbe interactions, offering promising avenues for the prevention and treatment of disorders such as inflammatory bowel disease, irritable bowel syndrome, and colorectal cancer.

Bowel Stiffness Assessed by Shear-Wave Ultrasound Elastography Predicts Disease Behavior Progression in Patients With Crohn's Disease

INTRODUCTION

There is a lack of reliable predictors of disease behavior progression in patients with Crohn's disease (CD). Real-time shear-wave elastography (SWE) is a novel method for evaluating tissue stiffness. However, its value for assessing CD has not yet been investigated. We aimed to explore the value of SWE and other ultrasound parameters at diagnosis in predicting CD behavior progression.

METHODS

We retrospectively collected data from patients with CD with the nonstenotic nonpenetrating disease (B1 phenotype based on the Montreal classification). All patients underwent intestinal ultrasound at baseline and were followed up. The end point was defined as disease behavior progression to stricturing (B2) or penetrating (B3) disease. Cox regression analysis was performed for the association between baseline characteristics and subsequent end points. In addition, a multivariate nomogram was established to predict the risk of disease behavior progression quantitatively.

RESULTS

A total of 130 patients with CD with B1 phenotype were enrolled. Twenty-seven patients (20.8%) developed B2 or B3 disease, with a median follow-up of 33 months. Multivariate analysis identified that SWE was the only independent predictor of disease behavior progression (hazard ratio 1.08, 95% confidence interval 1.03-1.12, P = 0.001). A reverse of the HR appeared at the cutoff 12.75 kPa. The nomogram incorporating SWE and other clinical characteristics showed a good prediction performance (area under the curve = 0.792).

DISCUSSION

Intestinal stiffness assessed using SWE is an independent predictor of disease behavior progression in patients with CD. Patients with CD with SWE >12.75 kPa at diagnosis are prone to progress toward stricturing or penetrating diseases.