Numerical Determination of SNR using an Anatomic Pixel Rat Brain Model

Introduction. The signal-to-noise ratio (SNR) is an accepted measure of the coil performance and at the same time SNR is an accepted standard for measurement of image quality in MRI, as the quality of the reconstructed image depends strongly on the SNR of the acquired MR signals. Analytical expressions based on the Maxwell equations, can be derived for the simplest cases of surface coils [1], but it is very difficult to derive expressions for more complex geometries due to the complicated mathematical framework involved. The numerical study of the electromagnetic behavior for MRI coils and biological tissues is a good alternative. A numerical method based on the Finite Element Method (FEM) to compute the SNR in a circular-shaped coil is presented here, and this was compared with the SNR calculated by a Varian algorithm from a real rat brain phantom image obtained with a 7T MRI system in our laboratory