Fast Patient Specific Estimation of Electric Fields for a Transmit Array from B1+ Measurements

Alessandro Sbrizzi¹, Hans Hoogduin¹, Gerard L. G. Sleijpen², Jan J. Lagendijk¹, Peter Luijten¹, Cornelis A. T. van Den Berg¹

An outstanding challenge of parallel transmission is to obtain patient specific information about the electric fields. In this work we describe how information about the electric fields in a body can be gained from standard transverse B1+ magnitude measurements. The novel method exploits the close relationship between electric and B1+ fields when they are expressed in terms of a Bessel/Fourier expansion. This approach allows a patient specific estimation of the electric fields and, in addition, requires only some seconds of computation time. The novel method is validated by means of FDTD simulations and in vivo measurement.