Sensitivity of TMS-induced electric fields to the uncertainty in coil placement and brain anatomy

A computational framework for statistically characterizing electric (E-) fields generated during transcranial magnetic stimulation (TMS) is presented. The framework combines a high dimensional model representation (HDMR) technique with a quasi-static finite-difference (QSFD) simulator to obtain statistics of E-fields due to uncertainty in the TMS setup and patient's brain anatomy. Application of the proposed computational framework shows that E-fields induced by TMS are highly sensitive to the position and orientation of TMS coils, as well as the size of patient's brain.