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Effect of Bladder Wall Thickness Through Change of Bladder Volume and Material Properties on Detrusor activity Study

체적의 변화를 통한 방광벽 두께와 기계적 재료상수 변화가 배뇨근 활동에 미치는 영향

  • Jun, Su-Min (Department of Mechanical Engineering, Sogang Univ.) ;
  • Lee, Moon-Kyu (Department of Mechanical Engineering, Sogang Univ.) ;
  • Choi, Bum-Kyoo (Department of Mechanical Engineering, Sogang Univ.)
  • Received : 2011.03.23
  • Accepted : 2012.01.14
  • Published : 2012.05.01

Abstract

The structural and functional disorder of a detrusor induces a bladder hypertrophy and degenerates a bladder muscle gradually by preventing normal urination. Thus, the thickness of the bladder wall has been increased in proportion to the degree of bladder outlet obstruction. In this study, the mechanical characteristics of the detrusor is analyzed for the physical properties and the thickness changes of the bladder muscle using a mathematically analytic method. In order to obtain the mechanical property of the bladder muscle, the tensile test of porcine bladder tissue is performed because its property is similar to that of human. The result of tensile test is applied to the mathematically model as Mooney Rivlin coefficients which represent the hyperelastic material. The model of the bladder is defined as the spherical shape with the initial volume of 50ml. The principal stress and strain according to the thickness are analyzed. Also, computer simulations for three types of the material property for the model of the bladder are performed based on the fact that the stiffness of the bladder is weakened as the progress of the benign prostatic hyperplasia. As a result, the principal stress is 341kPa at the initial thickness of 2.2mm, and is 249kPa at 6.5mm. As the bladder wall thickness increases, the principal stress decreases. The principal stress and strain decrease as the stiffness of the bladder decreases under the same thinkness.

Keywords

References

  1. Abrams, P. and Wein, A., "Introduction: Overactive Bladder and its Itreatments," Urology, Vol. 55, No. 5, Suppl. 1, pp. 1-2, 2000. https://doi.org/10.1016/S0090-4295(99)00523-3
  2. Korean Continence Society, "Textbook of Voiding Dysfunction and Female Urology," Ilchokak, pp. 234-236, 2009.
  3. Oelke, M., Hofner, K., Jonas, U., De La Rosette, J., Ubbink, D. and Wijkstra, H., "Diagnostic Accuracy of Noninvasive Tests to Evaluate Bladder Outlet Obstruction in Men: Detrusor Wall Thickness, Uroflowmetry, Postvoid Residual Urine, and Prostate Volume," European Urology, Vol. 52, No. 3, pp. 827-835, 2007. https://doi.org/10.1016/j.eururo.2006.12.023
  4. Kelly, C. E., "The Relationship Between Pressure Flow Studies and Ultrasound-Estimated Bladder Wall mass," Reviews in Urology, Vol. 7, No. 6, pp. S29-34, 2005.
  5. Mirone, V., Imbimbo, C., Longo, N. and Fusco, F., "The Detrusor Muscle: an Innocent Victim of Bladder Outlet Obstruction," European Urology, Vol. 51, No. 1, pp. 57-66, 2007. https://doi.org/10.1016/j.eururo.2006.07.050
  6. Hakenberg, O. W., Linne, C., Manseck, A. and Wirth, M. P., "Bladder Wall Thickness in Normal Adults and Men With Mild Lower Urinary Tract Symptoms and Benign Prostatic Enlargement," Neurourol Urodynamics., Vol. 19, No. 5, pp. 585-93, 2000. https://doi.org/10.1002/1520-6777(2000)19:5<585::AID-NAU5>3.0.CO;2-U
  7. Bostwick, D. G., Cooner, W. H., Denis, L., Jones, G. W., Scardino, P. T. and Murphy, G. P., "The Association of Benign Prostatic Hyperplasia and Cancer of The Prostate," Vol. 70, Suppl. 1, pp. 291-301, 1992. https://doi.org/10.1002/1097-0142(19920701)70:1+<291::AID-CNCR2820701317>3.0.CO;2-4
  8. Manieri, C., Carter, S. S. C., Romano, G., Trucchi, A., Valenti, M. and Tubaro, A., "The diagnosis of bladder outlet obstruction in men by ultrasound measurement of bladder wall thickness," The Journal of Urology, Vol. 159, No. 3, pp. 761-775, 1998. https://doi.org/10.1016/S0022-5347(01)63723-6
  9. Jin, Y. M. and Kim, T. K., "The Usefulness of Bladder Wall Thickness Measurement Using Ultrasound in Patients With Benign Prostatic Hyperplasia," Korean Journal of Urology, Vol. 43, No. 7, pp. 598-604, 2002.
  10. Kessler, T. M., Gerber, R., Burkhard, F. C., Studer, U. E. and Danuser, H., "Ultrasound Assessment of Detrusor Thickness in Men Can It Predict Bladder Outlet Obstruction and Replace Pressure Flow Study?" The Journal of Urology, Vol. 175, No. 6, pp. 2170-2713, 2006. https://doi.org/10.1016/S0022-5347(06)00316-8
  11. Fransisco, C., John, H., Vikram, K. and Andrea, T., "Bladder Wall Thickness in Overactive Bladder: Does It Have a Role?" European Urology Supplements, Vol. 8, No. 9, pp. 769-771, 2009. https://doi.org/10.1016/j.eursup.2009.05.002
  12. Yeung, C. K., Screedhar, B., Leung, Y. F. and Sit, K. Y., "Correlation between Ultrasonographic Bladder Measurements and Urodynamic Findings in Children with Recurrent Urinary Tract Infection," British Journal of Urology International, Vol. 99, No. 3, pp. 651-655, 2007. https://doi.org/10.1111/j.1464-410X.2006.06580.x
  13. Korkmaz, I. and Rogg, B., "A Simple Fluid-Mechanical Model for the Prediction of the Stress- Strain Relation of the Male Urinary Bladder," Journal of Biomechanics, Vol. 40, No. 3, pp. 663-668, 2007. https://doi.org/10.1016/j.jbiomech.2006.02.014
  14. Fung, Y. C., "Biomechanics," Springer, p. 35, 1993.
  15. Wagg, A. and Fry, C. H., "Visco-Elastic Properties of Isolated Detrusor Smooth Muscle," Scandinavian Journal of Urology and Nephrology, Vol. 201, No. 201, pp. 12-18, 1999.
  16. Sotirios, K., Fiona, B., Jenny, S., Eileen, I. and John F., "Regional Biomechanical and Histological Characterization of the Passive Porcine Urinary Bladder: Implications for Augmentation and Tissue Engineering Strategies," Biomaterials, Vol. 30, No. 2, pp. 266-275, 2009. https://doi.org/10.1016/j.biomaterials.2008.09.034
  17. Damaser, M. S. and Lehman, S. L., "The Effect of Urinary Bladder Shape on Its Mechanics During Filling," Journal of Biomechanics, Vol. 28, No. 6, pp. 725-732, 1995. https://doi.org/10.1016/0021-9290(94)00169-5
  18. Pel, J. J. M. and van Mastrigt, R., "Development of a CFD Urethral Model to Study Flow Generated Vortices under Different Conditions of Prostatic Obstruction," Physiological Measurement, Vol. 28, No. 1, pp. 13-23, 2007. https://doi.org/10.1088/0967-3334/28/1/002
  19. Kuo, H. C., Chen, Y. C. and Chancellor, M. B., "Transabdominal Ultrasound Measurement of Detrusor Wall Thickness in Patients with Overactive Bladder," Tzu Chi Medical Journal, Vol. 21, No. 2, pp. 129-135, 2009. https://doi.org/10.1016/S1016-3190(09)60024-0
  20. Oelke, M., Hofner, K., Jonas, U., Ubbink, D., De La Rosette, J. and Wijkstra, H., "Ultrasound Measurement of Detrusor Wall Thickness in Healthy Adults," Neurourol Urodyn, Vol. 25, No. 4, pp. 308-317, 2006. https://doi.org/10.1002/nau.20242
  21. Hong, S. J., "Benign Prostatic Hyperplasia: Multiple Factors for Prostate Tissue Change with Aging," Korean Journal of Urology, Vol. 46, No. 6, pp. 46547-46554, 2005.