Method of dynamically compensating for magnetic field heterogeneity in magnetic resonance imaging

US9377517B2 · kind B2 · utility

Assignee

• UNIVERSITAETSKLINIKUM FREIBURG · DE

Inventors

• Walter Witschey · Philadelphia, US
• Maxim Zaitsev · Glückstadt, DE
• Jurgen Hennig · Glückstadt, DE
• Gerrit Schultz · Glückstadt, DE
• Daniel Gallichan · Glückstadt, DE

Key dates

• Filing date: Mar 8, 2012
• Grant date: Jun 28, 2016
• Expiry date: Apr 13, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/3875
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method to compensate for the magnetic field heterogeneity inside an object of investigation in a MR device obtains an uncorrected magnetic field distribution of the object and executes an MR sequence with a desired k-space coverage by applying RF pulses to generate a transverse magnetization within the object. MR signal data is recorded, magnetic field shimming parameters are dynamically updated and MR signal data are reconstructed to produce images or localized spectroscopic data. Artifacts in a reconstructed image resulting from an uncorrected magnetic field distribution are suppressed by temporally separating MR signals originating from at least two different sub-volumes within a volume of transverse magnetization by generating a nonlinear phase distribution within the object and by dynamically updating shimming parameters to compensate for the field inhomogeneity distributions within the different sub-volumes in the volume of transverse magnetization.