# An in silico biomechanical analysis of the stent–esophagus interaction

## Abstract

Despite all technological innovations in esophageal stent design over the past 20 years, the association between the stent design’s mechanical behavior and its effect on the clinical outcome has not yet been thoroughly explored. A parametric numerical model of a commercially available esophageal bioresorbable polymeric braided wire stent is set up, accounting for stent design aspects such as braiding angle, strut material, wire thickness, degradation and friction between the wires comprising a predictive tool on the device’s mechanical behavior. Combining this tool with complex multilayered numerical models of the pathological in vivo stressed, actively contracting and buckling esophagus could provide clinicians and engineers with a patient-specific window into the mechanical aspects of stent-based esophageal intervention. This study integrates device and soft tissue mechanics in one computational framework to potentially aid in the understanding of the occurrence of specific symptoms and complications after stent placement.

### Keywords

Bioresorbable stent Polymeric braided wire stent Virtual implantation Esophageal stenting Esophageal modeling Finite element analysis Constitutive modeling Active muscle contraction Patient-specific Zero-stress state Buckling Peristalsis## Notes

### Acknowledgements

The authors gratefully acknowledge Peter Dubruel, Ph.D., David De Wilde, Ph.D., and Wouter Kappelle, MD, for their valuable support and assistance. We also thank MPT Europe for giving us access to the radial stent compression unit, which greatly assisted the mechanical characterization of the studied stent samples. This research was supported by the Flanders Innovation & Entrepreneurship Agency, strategic basic research Grant No.141014.

### Compliance with ethical standards

### Conflicts of interest

The authors declare that they have no conflict of interest.

## Supplementary material

### References

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