A Numerical Study to Precise the Estimation of the “Good” Mound Height in Endoscopic Treatment of VUR

Mehdi Shirazi¹, Zahra Jahanabadi¹, Zeinab Hooshyar², Zahra Mortazavinia³, Alireza Mehdizadeh^4*, Mojtaba Taherisadr⁵

¹Urology Department, Shiraz University of Medical Science, Shiraz, Iran.
²Mechanical Engineering, Shiraz University, Shiraz, Iran.
³école Polytechnique de Montréal, Mechanical Engineering Department, Montreal, Canada.
⁴Shiraz University of Medical Science (SUMS), Shiraz, Iran.
⁵Biomedical Engineering Department, Isfahan University, Esfahan, Iran.

DOI: 10.4236/jbise.2014.711091                

Abstract

Objective: To ascertain the technique and volume of injection increasing the success rate of endoscopic VUR treatment, we develop a novel method to numerically describe the relationship between intramural ureter anatomy, intravesical pressure, and the theoretical mound height needed for adequate treatment. Methods: The main purpose of this study is to construct a finite element simulation of intramural ureter and injected mound which aims to numerically define the relationship between indexes which have influence in VUR endoscopic treatment. Using linearization software and numerically simulation data, the relationship between effective indexes has been derived. Results: By linearization of the effective parameters of different finite element models, the relationship between effective parameters in filling phase is derived as: H (m) = ﹣0.003467 (m) + 0.7864D (m) + 0.000233. This equation depicts adequate injected mound height as a function of internal diameter and intramural length, H = f(L, D). Conclusion: Using numerical simulation, we introduced the novel formula to predict the height of injected mound in endoscopic VUR treatment. As a result of this study, in order to increasing the success rate of this treatment, the ratio of mound height to intramural ureter diameter should be approximately 78%.

Keywords

Mound Height, Endoscopic Treatment, Vesico Ureteral Reflux, Numerical Simulation

Conflicts of Interest

The authors declare no conflicts of interest.

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