Finite element analysis of transcranial electrical stimulation for intraoperative monitoring

Transcranial electrical stimulation (TES) is an important intraoperative monitoring procedure. When neurosurgery is performed at certain difficult locations within the central nervous system (CNS), TES evaluates CNS functions during surgical manipulations to prevent post-operative complications. However, the parameters currently utilized in TES are usually experimentally determined which may not be optimal. We have constructed a finite elements model to analyze TES based on a 2D volume conductor model. A realistically shaped simulation domain is constructed by taking the inhomogeneous electrical conductivity values of different tissues into account. Laplace´s equation is numerically solved with a set of appropriately selected boundary conditions using the finite element method. Our simulation has yielded clear maps of potential and current distributions within the intracranial space, providing valuable information to optimize the TES procedure.