Resistive Tapered Stripline (RTS) in Electroencephalogram Recordings During MRI

Abstract

A purely resistive stripline lead is introduced to reduce the specific absorption rate (SAR) increase due to the presence of leads in electroencephalography (EEG) measurements during magnetic resonance imaging. Discontinuities in the resistivity profile of the stripline introduce high-frequency inductive impedance that is not present in the low-frequency band of the EEG recordings. The changes in SAR introduced by the resistive tapered stripline (RTS) are studied using the finite-difference time-domain (FDTD) algorithm on a spherical phantom that models the human head. The FDTD simulations predict a reduction of the peak SAR when using RTS versus conventional resistive carbon fibers. Furthermore, our FDTD simulations have been validated on a simple prototype that exhibits no temperature increase on a spherical phantom.