Modeling the interaction between navigation probe and deformable brain tissue based on finite element analysis: Preliminary study

Image-guided surgery (IGS) plays an important role in clinical treatment and interventions. It is a surgical technique utilizing computerized equipment to identify the anatomical structures based on preoperative image data i.e. computed tomography (CT) and magnetic resonance imaging (MRI) and in finding the most suitable surgical path to reach these structures. In the medical discipline of neurosurgery where IGS is frequently used, it has been noted that the brain undergoes varying levels of deformation at different stages of the operative procedure. Current navigation software based on preoperative imaging information cannot accurately describe such deformations could subsequently lead to surgical localization error. This paper presents modeling of soft tissue deformation based on finite element analysis, which includes the geometry model, material properties used for the model, finite element mesh, and boundary constraint conditions. The navigation probe-tissue interaction is modeled by conducting stress-strain analysis on the brain model using a visco-elastic material model. The simulation closely depicts the actual scene; the results show that the highest deformation occurs at the probe tip when the probe goes in contact with the brain tissue. After the probe breaks the tissue´s surface tension, the stress occurs at the surrounding region of the probe. This biomodeling analysis provides useful information concerning brain tissues deformation when under external stress which may help in building biomechanical deformation model to predict the intraoperative brain shift.