An artificial model for studying fluid dynamics in the obstructed and stented ureter

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Urology

Background:

• Ureteral stents are essential for managing urinary tract obstructions but can fail due to factors like bacterial colonization and encrustation.
• Understanding the complex fluid dynamics within obstructed and stented ureters is critical for preventing complications such as kidney damage from elevated renal pelvis pressures.

Purpose of the Study:

• To develop and validate a microfluidic ureter model (UM) for simulating fluid dynamics in obstructed and stented ureters.
• To quantify the relationship between fluid viscosity, flow rate, obstruction level, and renal pelvis pressure.

Main Methods:

• A transparent microfluidic device (ureter model, UM) was designed based on measurements from pig ureters.
• Renal pelvis pressure was measured by varying fluid viscosity (μ), volumetric flow rate (Q), and obstruction level (OB%).
• Particle image velocimetry (PIV) was demonstrated as a potential application for flow visualization.

Main Results:

• The study successfully quantified critical combinations of μ, Q, and OB% that lead to elevated renal pelvis pressures.
• The developed UM provides a platform for in-vitro investigation of fluid dynamics in stented ureters.

Conclusions:

• The microfluidic ureter model offers a valuable tool for studying fluid dynamics in stented ureters and identifying conditions that may lead to stent failure and kidney damage.
• This research can inform the design of more effective ureteral stents and clinical management strategies.