MRI‐based wireless determination of the transfer function of a linear implant: Introduction of the transfer matrix

摘要

PurposeWe introduce the transfer matrix (TM) that makes MR‐based wireless determination of transfer functions (TFs) possible. TFs are implant specific measures for RF‐safety assessment of linear implants. The TF relates an incident tangential electric field on an implant to a scattered electric field at its tip that generally governs local heating. The TM extends this concept and relates an incident tangential electric field to a current distribution in the implant therewith characterizing the RF response along the entire implant. The TM is exploited to measure TFs with MRI without hardware alterations.