MRI method of calculating and generating spatially-tailored parallel radio frequency saturation fields

摘要

A method for producing magnetic resonance images of a subject in which artifacts resulting from a localized source, such as from pulsatile blood flow, are substantially mitigated is provided. The location of an artifact source, at which spins corresponding to flowing blood are located, is identified. Using this identified artifact source location, a region-of-saturation is calculated. A magnetic resonance imaging (MRI) system is then directed to perform a pulse sequence that results in the generation of a radio frequency (RF) saturation field being produced by an array of RF transmission coils. The RF saturation field is sized and shaped according to the calculated region-of-saturation. Images are reconstructed from image data acquired after application of the RF saturation field, and artifacts related to motion of the spins at the identified location of the artifact source are substantially mitigated in these images.

主权项

1. A method of mitigating an image artifact resulting from an artifact source using a magnetic resonance imaging (MRI) system, the steps of the method comprising:
a) providing an initial magnetic resonance (MR) image acquired with an MRI system; b) identifying in the provided initial MR image, a location of an artifact source at which spins corresponding to the artifact source are located; c) calculating, based on the initial MR image data, a region-of-saturation using the identified location of the artifact source; d) directing the MRI system to perform a magnetic resonance pulse sequence that includes:
i) applying at the location of the artifact source with an array of radio frequency (RF) transmission coils, an RF saturation field that is sized and shaped according to the calculated region-of-saturation;ii) acquiring MR image data following application of the RF saturation field; and e) reconstructing from the acquired MR image data, a reconstructed MRI image in which MR image artifacts related to a motion of the spins at the identified location of the artifact source are mitigated from the performance of steps d)i) and d)ii).