Advertisement

Simulation of Existing and Future Electromechanical Shunt Valves in Combination with a Model for Brain Fluid Dynamics

  • Inga Margrit ElixmannEmail author
  • M. Walter
  • M. Kiefer
  • S. Leonhardt
Conference paper
Part of the Acta Neurochirurgica Supplementum book series (NEUROCHIRURGICA, volume 113)

Abstract

Several models are available to simulate raised intracranial pressure (ICP) in hydrocephalus. However, the hydrodynamic effect of an implanted shunt has seldom been examined. In this study, the simple model of Ursino and Lodi [14]is extended to include (1) the effect of a typical ball-in-cone valve, (2) the effect of the size of the diameter of the connecting tube from valve to abdomen, and (3) the concept of a controlled electromechanical shunt valve in overall cerebrospinal fluid dynamics.

By means of simulation, it is shown how a shunt can lower ICP. Simulation results indicate that P and B waves still exist but at a lower ICP level and that, due to the exponential pressure-volume curve, their amplitude is also considerably lowered. A waves only develop if the valve is partially blocked. The resulting ICP is above the opening pressure of the valve, depending on the drain and resistance of the shunt.

The concept of a new electromechanical shunt was more successful than the traditional mechanical valves in keeping ICP at a desired level. The influence of the patient’s movements or coughing on ICP as well as the body position affecting the reference ICP, which can be measured, has not yet been modeled and should be addressed in future using suitable algorithms.

Keywords

Hydrocephalus Shunt Mechatronic/electromechanical valve Model A waves B waves 

Notes

Acknowledgements

The authors thank the German Federal Ministry of Science and Education (BMBF) for financial support of the BMBF project “iShunt”.

Conflicts of interest statement Dr. M. Kiefer has received financial support in the past for activities other than this research, from Raumedic AG, Helmbrecht, Germany. All other authors declare that they have no conflict of interest.

References

  1. 1.
    Aschoff A (1994) In-vitro-Testung von Hydrocephalus-Ventilen. Professorial dissertation, Heidelberg University, Heidelberg, pp 86–179Google Scholar
  2. 2.
    Avezaat CJJ, Van Eijndhoven JHM (1979) Cerebrospinal fluid pulse pressure and intracranial volume-pressure relationships. J Neurol Neurosurg Psychiatry 42:687–700PubMedCrossRefGoogle Scholar
  3. 3.
    Di Rocco C, Pettorossi VE, Caldarelli M, Mancinelli R, Velardi F (1978) Communicating hydrocephalus induced by mechanically increased amplitude of the intraventricular cerebrospinal fluid pressure: experimental studies. Exp Neurol 59:40–52PubMedCrossRefGoogle Scholar
  4. 4.
    Egnor M, Zheng L, Rosiello A, Gutman F, Davis R (2002) A model of pulsations in communicating hydrocephalus. Pediatr Neurosurg 36:281–303PubMedCrossRefGoogle Scholar
  5. 5.
    Ginggen A, Tardy Y, Crivelli R, Bork T, Renaud P (2008) A telemetric pressure sensor system for biomedical applications. IEEE Trans Biomed Eng 55:1374–1381PubMedCrossRefGoogle Scholar
  6. 6.
    Greitz D (2004) Radiological assessment of hydrocephalus: new theories and implications for therapy. Neurosurg Rev 27:145–165PubMedGoogle Scholar
  7. 7.
    Hara M, Kadowaki C, Konishi Y, Ogashiwa M, Numoto M, Takeuchi K (1983) A new method for measuring cerebrospinal fluid flow in shunts. J Neurosurg 58:557–561PubMedCrossRefGoogle Scholar
  8. 8.
    Krause I, Jetzki S, Rehbaum H, Linke S, Kiefer M, Walter M, Leonhardt S (2009) Dynamic bench testing of shunt valves. In: Hydrocephalus. Baltimore, p 98Google Scholar
  9. 9.
    Kunze G, Göhler KG, Reichenberger R. (2009) Entwicklung des Raumedic TD1 readP, ein erster Schritt auf dem Weg zum idealen, telemetrischen Hirndruckmesssystem. Sektionstagung, Congress Proceedings, Homburg, Germany, p 56Google Scholar
  10. 10.
    Marmarou A, Shulman K, Rosende RM (1978) A nonlinear analysis of the cerebrospinal fluid system and intracranial pressure dynamics. J Neurosurg 48:332–344PubMedCrossRefGoogle Scholar
  11. 11.
    Miyake H, Ohta T, Kajimoto Y, Matsukawa M (1997) A new ventriculoperitoneal shunt with a telemetric intracranial pressure sensor: clinical experience in 94 patients with hydrocephalus. J Neurosurg 40:931–935CrossRefGoogle Scholar
  12. 12.
    Mnomani L, Alkharabscheh AR, Al-Zu’bi N, Al-Nuaimy W (2009) Instantiating a mechatronic valve schedule for a hydrocephalus shunt. Conf Proc IEEE Eng Med Biol Soc 31:749–752Google Scholar
  13. 13.
    Richard KE, Block FR, Weiser RR (1999) First clinical results with a telemetric shunt-integrated ICP-sensor. Neurol Res 1:117–120Google Scholar
  14. 14.
    Ursino M, Lodi CA (1997) A simple mathematical model of the interaction between intracranial pressure and cerebral hemodynamics. J Appl Physiol 82:1256–1269PubMedGoogle Scholar
  15. 15.
    Ursino M, Ter Minassian A, Lodi CA, Bydon L (2000) Cerebral hemodynamics during arterial and CO2 pressure changes: in vivo prediction by a mathematical model. Am J Physiol Heart Circ Physiol 279:H2439–H2455PubMedGoogle Scholar
  16. 16.
    Walter M (2002) Mechatronische Systeme für die Hydrozepha­lustherapie. Shaker, Aachen, pp 29–58Google Scholar
  17. 17.
    Walter M, Jetzki S, Leonhardt S (2005) A model for intracranial hydrodynamics. In: IEEE annual engineering in medicine and biology conference, Shanghai, Congress Proceedings, pp 5603–5606Google Scholar

Copyright information

© Springer-Verlag/Wien 2012

Authors and Affiliations

  • Inga Margrit Elixmann
    • 1
    Email author
  • M. Walter
    • 1
  • M. Kiefer
    • 2
  • S. Leonhardt
    • 1
  1. 1.Helmholtz-Institute for Biomedical EngineeringRWTH Aachen UniversityAachenGermany
  2. 2.Department of NeurosurgerySaarland UniversityHomburg-SaarGermany

Personalised recommendations