Computational Fluid Dynamics Model of Bladder-Urethra System for SUI

With aging population and people’s demands to improve their quality of life, stress urinary incontinence (SUI) patients who need to be cured are increasing. Mechanics plays an important role in the formation of SUI. Muscles and other soft tissue in pelvic cavity, which is the direct control of the mechanical mechanism of urethral closure, will be important scientific issues in the field. Establishing mathematical model of bladder-urethra system can provide a basic analysis for the disabled urethra closure of SUI in clinic. With the help of computational fluid dynamic (CFD), we developed a three-dimensional urodynamic bladder-urethra system, which includes bladder, bladder neck, prostate and urethra, and the realistic recirculation process of the urinary bladder during the physiological voiding process in conjunction with a flow simulation through the female urinary bladder and urethra is presented. The computational results show that a dead-water zone and a zone of secondary flow occur, and that is independent of the shape of the prostatic urethra. For the pathological prostata, the extreme constriction of the prostatic urethra results in an additional wide-stretched dead-water zone. The simulation results not only can improve urinary incontinence surgery for clinicians, but also can provide a basis for theoretical analysis.