METHOD AND APPARATUS FOR MAGNETIC RESONANCE DATA ACQUISITION USING A MULTIPOINT DIXON TECHNIQUE

摘要

In a method and magnetic resonance (MR) apparatus to acquire MR data from a subject, a predetermined spectral model of a multipoint Dixon technique is used that includes at least two spectral components with respective associated relaxation rates, a first phase due to field inhomogeneities; and a second phase due to eddy current effects. MR data are acquired using a bipolar multi-echo MR measurement sequence for multiple image points wherein, for each image point, the multi-echo MR measurement sequence alternately uses positive and negative readout gradient fields for the readout of MR signals of the MR data at at least three echo times. The at least two spectral components are determined based on the MR data.

主权项

1. A method for acquiring magnetic resonance data from an examination subject, comprising:
operating a magnetic resonance data acquisition unit, that generates a basic magnetic field in which an examination subject is situated, according to a bipolar multi-echo data acquisition sequence, to acquire magnetic resonance data from the examination subject for multiple image points by, for each image point, with alternatingly activating positive and negative readout gradient fields during which magnetic resonance signals are read out at at least three echo times, said activation of said gradient fields producing eddy currents in said data acquisition unit by interaction with said basic magnetic field; providing said magnetic resonance data to a computerized processor and, in said computerized processor, operating on said magnetic resonance data with a spectral model of a multipoint Dixon technique that relates said magnetic resonance data to at least two spectral components of said magnetic resonance signals and respective, associated relaxation rates of said at least two spectral components, and a first phase of said magnetic resonance signals due to field inhomogeneities of said basic magnetic field, and a second phase due to effects of said eddy currents, to implement an at least partially numerical determination of said at least two spectral components, said relaxation rates, said first phase, and said second phase; and making said at least two spectral components available in electronic form at an output of said processor in a format allowing reconstruction of an in-phase image and two out-of-phase images according to the multipoint Dixon technique that is modeled by said spectral model.