Particle Accumulation in Ureteral Stents Is Governed by Fluid Dynamics: In Vitro Study Using a "Stent-on-Chip" Model.

Objective: To investigate the correlation between fluid dynamic processes and deposition of encrusting particles in ureteral stents.

Materials And Methods: Microfluidic models (referred to as "stent-on-chip" or SOC) were developed to replicate relevant hydrodynamic regions of a stented ureter, including drainage holes and the cavity formed by a ureteral obstruction. Computational fluid dynamic simulations were performed to determine the wall shear stress (WSS) field over the solid surfaces of the model, and the computational flow field was validated experimentally.

Engineering solutions to ureteral stents: material, coating and design.

Introduction: An ideal stent would offer simple insertion and removal with no discomfort and/or migration, it would have no biofilm formation or encrustation and would also maintain the patient's quality of life.

Material And Methods: In this mini-review, we outlined the engineering developments related to stent material, design and coating.

Results: There have been a wide variety of in-vitro, model-based, animal-based and clinical studies using a range of commercial and non-commercial stents.