Category: Education, Simulation & Virtual Reality

MP19-21 - Checking antireflux effect of an innovative ureteral stent: a simplified model simulation

Sat, Sep 22
2:00 PM - 4:00 PM

Introduction & Objective :

One of the main side effects of double J ureteral stents is the vesicoureteral reflux (VUR). For this reason, we propose an innovative intraureteral stent that could avoid VUR with a new distal anchoring system. However, to reduce preclinical trial we use in silico simulations in early design stages that allow us to improve the new urinary designs.

Methods :

Two different models of the distal part of a ureteral stent (Figure 1) in its maximum and minimum lumen during diuresis peak were used to perform a simulation. We evaluate our new design of BraidStent via the Computational fluid dynamics module of COMSOL Multiphysics. A 10 second simulation was made to analyze the flow of the urine in both states. Boundary conditions applied on the model were obtained from previous in vivo experiments during diuresis peak: 3 and 2 mmHg for inlet and outlet flow, respectively.

Results :

The difference of pressure between proximal and distal sides of the ureter model provoke the movement of urine through ureter as can be seen in Figure 2. Streamlines go uniformly even when fluid overcome the stent. Also, streamlines distance shows appropriate velocity magnitude and pressure distribution along the simulated model showing no streamlines in countercurrent. The comparison of both magnitudes determines that, under above mentioned conditions, our distal ureteral anchoring system does not alter the ureteral urine fluid dynamics.

Conclusions :

Although these initial computational simulations show a stable urine  dynamic flow in stented ureter, further studies with more complex models must be done to check additional physiological features, such as, peristalsis effect in urine flow.

Enrique Mancha

Caceres, Extremadura, Spain

Juan Carlos Gomez-Blanco

Caceres, Extremadura, Spain

J.B. Pagador

caceres, Extremadura, Spain

Francisco Sánchez Margallo

Caceres, Extremadura, Spain

Federico Soria

Endoscopy-Endourology Coordinator
Minimally Invasive Surgery Centre Jesus Uson. Spain
caceres, Extremadura, Spain

Dr. Federico Soria. Chairman. ENIUS (European network of multidisciplinary research to improve the urinary stents. European Cooperation in Science &Technology. Framework Programme Horizon 2020). (

Dr. Federico Soria is Endoscopy Coordinator in Jesus Uson Minimally Invasive Surgery Centre (Spain) a multidisciplinary institution devoted to Research, Innovation and Training in health sciences.
Dr. Soria research is focused on Traslational Research (Preclinical) Minimally Invasive Surgery Urological techniques and devices. A special focus area is urinary tract stents design: Biodegradable, Drug eluting stents and metallic designs and Biomaterials. Researcher in more than 30 research projects, 16 as a principal investigator. Three patents in Biomedicine devices (ureteral stents).