high performance computing on graphics processing units: hgpu.org

During brachytherapy and biopsy, significant prostate motion (including deformation) can occur, causing the target lesion to move during the procedures. One method to improve the accuracy of needle tip placement during these percutaneous procedures is to use a 3D Finite Element (FE) model to estimate the amount of needle deflection. This model is based on the available mechanical properties of the material (shape, stiffness and density). In this study, the needle deflection during brachytherapy will be modelled using an FE model and compared with experimental results. In order to predict a correct needle deflection using FE, boundary conditions have to be defined accurately. Anatomically correct prostate models that include urethra can improve the accuracy of the FE model. However, computational time of an FE model increases with the complexity of the model. The first aim of this project is to make a real time FE model of the prostate and the surrounding tissues and deform it using a needle guide. During the experiments, several markers are put on top of the prostate, will be tracked and compared with the FE model. Finally, a needle is inserted and the deflection will be compared between the experimental results and an FE model. To create an FE model which runs in real-time, the open source framework SOFA has been used. SOFA targets at real-time medical simulations and allows the user to model the deformation of the prostate. The needle insertion is done using a plug-in which enables SOFA to calculate needle deflection. This study shows that both prostate deformation and needle insertion can be predicted which can be used for e.g. autonomous robotic surgery.