Patent ID: 9097779
Filing Date: 2015-08-04
Classification: G01R

Abstract:
1. A method for magnetic field insensitive chemical exchange saturation transfer (CEST) imaging in magnetic resonance tomography, comprising: operating a magnetic resonance data acquisition unit, comprising a plurality of radio-frequency (RF) coils and a basic field magnet that generates a basic magnetic field, by detecting, with said RF coils, magnetic resonance (MR) signals from bound protons of a substance and by emitting at least one RF pulse that saturates said MR signals and at least one RF pulse that excites said MR signals; with said RF pulses generated by said RF coils, producing a magnetization in each point in space as a function of a spatial distribution of the basic magnetic field, of a spatial distribution of respective RF fields generated by the RF coils, of a time course of a field gradient that is activated during excitation of said MR signals, a time envelope function of a respective RF pulse, and a predetermined frequency shift; and shaping at least one of said RF pulses for saturation of the MR signals for each RF coil as a solution of a minimization problem in a computerized processor in which a weighted sum is minimized, which exhibits at least two norms selected from the group consisting of the norm of the magnetization of free water protons in each point in space, the norm of a deviation of the magnetization of the bound protons from an inverted magnetization in each point in space, and the norm of the magnetization of protons with a shift inverted with respect to the predetermined frequency shift in each point in space.