טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentSamoocha Or
SubjectDesign, Fabrication and Analysis of Robotic Device for
Prevention of Shunt Occlusions
DepartmentDepartment of Mechanical Engineering
Supervisor Professor Moshe Shoham
Full Thesis text - in Hebrew Full thesis text - Hebrew Version


Abstract

Hydrocephalus is a neurological disorder resulting from an imbalanced formation and absorption of cerebrospinal fluid (CSF). The most common treatment for this disorder involves implanting a silicone shunt.


Although this treatment is usually effective, shunt related complications are common. Tissue obstruction is the most common cause of shunt failure.


This thesis depicts an electromechanical device that was designed, analyzed, fabricated and tested in order to prevent shunt obstruction. This new device will substitute the perforated part of the shunt that often tends to be obstructed. This self cleaning shunt was designed to prevent the tissue growth inside the shunt and it can function adequately for a life time.


The prevention of the perforation from being blocked is achieved by small vibration. The vibration is preformed by the inner parts that are located in the perforations of the tube. This movement is achieved by applying an altering magnetic field that causes the magnets that are connected to the inner parts to move in a certain movement (horizontally and vertically directions).


In order to know whether the device would be able to prevent blockages we needed to know the stroke length and shape of the movement that can be achieved. In order to acquire this data, a simulation is needed to be built.


An analytic simulation was problematic because of the complex structure of the device. Eventually it was decided to execute three simulations and to use finite element analysis (FEA) using software (Ansys). The first simulation was simplified FEA simulation, the second was simplified analytic simulation to verify the first simulation and the third simulation was a full FEA simulation based on the first verified one.


Following the last step that proved that this device is actually functional, the device parts were sent to production and then were assembled gently under a microscope. The final device was tested using a specially designed activation systems under different conditions.


All the experiments were photographed with a high frequency camera and were analyzed with image processing software that was specially written in Matlab for this purpose.


Experiments showed a high correlation between simulations and the real device. The movement stroke of the device seems to be able to clean the perforation and prevent blockages.