Back to results
US 2019/0162809 A1Published application
The image quality in dixon turbo spin echo sequences
AssigneeSiemens Healthcare GmbH
InventorsDominik Paul, Mario Zeller
Life of this patent
Estimating the term…
Abstract
In a magnetic resonance (MR) method and apparatus, first and second MR data are acquired from respective echo trains with gradient moments of one echo train being in a sequence that is an inversion of at least a portion of the sequence of gradient moments in the second echo train. The MR signals are acquired from at least two substances in a volume of a subject, so that the relaxation of the respective nuclear spins influences the manner by which the first and second data are entered into k-space, so that when an image is reconstructed, the filter effect induced by such relaxation is compensated for.
Claims9
A method for acquiring magnetic resonance (MR) data using an MR data acquisition scanner comprising a radio-frequency (RF) antenna arrangement and a gradient coil arrangement, said method comprising:
- generating control signals in a computer and providing said control signals from said computer to said MR data acquisition scanner so as to acquire first MR data from a predetermined volume of a subject, by exciting nuclear spins of two predetermined substances in said predetermined volume and by operating said gradient coil arrangement so as to acquire said first MR data during said first echo train at respective time intervals during which the nuclear spins of said two predetermined substances occur in phase;
- phase encoding said first MR data by operating said gradient coil arrangement so as to produce a phase-encoding gradient during said first echo train comprising gradient moments in one phase-encoding direction in a first predetermined sequence;
- operating said MR data acquisition scanner from said computer with said control signals so as to acquire second MR data during a second echo train, by operating said gradient coil arrangement so as to acquire said second MR data during said second echo train at respective time intervals during which the nuclear spins of said two predetermined substances differ in phase by 180°;
- with said control signals, operating said gradient coil arrangement during acquisition of said second MR data so as to produce a phase-encoding gradient having gradient moments also in said one phase-encoding gradient, with a second predetermined sequence;
- operating said gradient coils during the acquisition of said first MR data and during the acquisition of said second MR data with said control signals so that said second sequence is an inversion of at least a portion of said first sequence so that a first gradient moment in said second sequence corresponds to an nth gradient moment in said first sequence, and so that a second gradient moment in said second sequence corresponds to an (n−1)th gradient moment in said first sequence, with n being less than or equal to a length of each of said first echo train and said second echo train;
- and
- in said computer, reconstructing an MR image of said predetermined volume from said first MR data and said second MR data, and making said reconstructed image available in electronic form, as a data file, from said computer.
4 more elements
A magnetic resonance (MR) apparatus comprising:
- an MR data acquisition scanner comprising a radio-frequency (RF) antenna arrangement and a gradient coil arrangement;
- a computer configured to generate control signals and to provide said control signals from said computer to said MR data acquisition scanner so as to acquire first MR data from a predetermined volume of a subject, by exciting nuclear spins of two predetermined substances in said predetermined volume and by operating said gradient coil arrangement so as to acquire said first MR data during said first echo train at respective time intervals during which the nuclear spins of said two predetermined substances occur in phase;
- said computer being configured to operate said MR data acquisition scanner with said control signals so as to phase encode said first MR data by operating said gradient coil arrangement in order to produce a phase-encoding gradient during said first echo train comprising gradient moments in one phase-encoding direction in a first predetermined sequence;
- said computer being configured to operate said MR data acquisition scanner with said control signals so as to acquire second MR data during a second echo train, by operating said gradient coil arrangement in order to acquire said second MR data during said second echo train at respective time intervals during which the nuclear spins of said two predetermined substances differ in phase by 180°;
- said computer being configured to operate said gradient coil arrangement with said control signals during acquisition of said second MR data so as to produce a phase-encoding gradient having gradient moments also in said one phase-encoding gradient, with a second predetermined sequence;
- said computer being configured to operate said gradient coils with said control signals during the acquisition of said first MR data and during the acquisition of said second MR data so that said second sequence is an inversion of at least a portion of said first sequence so that a first gradient moment in said second sequence corresponds to an nth gradient moment in said first sequence, and so that a second gradient moment in said second sequence corresponds to an (n−1)th gradient moment in said first sequence, with n being less than or equal to a length of each of said first echo train and said second echo train;
- and
- said computer being configured to reconstruct an MR image of said predetermined volume from said first MR data and said second MR data, and to make said reconstructed image available in electronic form, as a data file, from said computer.
5 more elements
A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a computer system of a magnetic resonance (MR) apparatus having an MR data acquisition scanner comprising a gradient coil arrangement and a radio-frequency (RF) antenna arrangement, said programming instructions causing said computer to:
- generate control signals in a computer and provide said control signals from said computer to said MR data acquisition scanner so as to acquire first MR data from a predetermined volume of a subject, by exciting nuclear spins of two predetermined substances in said predetermined volume and by operating said gradient coil arrangement so as to acquire said first MR data during said first echo train at respective time intervals during which the nuclear spins of said two predetermined substances occur in phase;
- phase encode said first MR data by operating said gradient coil arrangement so as to produce a phase-encoding gradient during said first echo train comprising gradient moments in one phase-encoding direction in a first predetermined sequence;
- operate said MR data acquisition scanner from said computer with said control signals so as to acquire second MR data during a second echo train, by operating said gradient coil arrangement so as to acquire said second MR data during said second echo train at respective time intervals during which the nuclear spins of said two predetermined substances differ in phase by 180°;
- with said control signals, operate said gradient coil arrangement during acquisition of said second MR data so as to produce a phase-encoding gradient having gradient moments also in said one phase-encoding gradient, with a second predetermined sequence;
- operate said gradient coils during the acquisition of said first MR data and during the acquisition of said second MR data with said control signals so that said second sequence is an inversion of at least a portion of said first sequence so that a first gradient moment in said second sequence corresponds to an nth gradient moment in said first sequence, and so that a second gradient moment in said second sequence corresponds to an (n−1)th gradient moment in said first sequence, with n being less than or equal to a length of each of said first echo train and said second echo train;
- and
- reconstruct an MR image of said predetermined volume from said first MR data and said second MR data, and make said reconstructed image available in electronic form, as a data file, from said computer.
4 more elements
Dependencies are inferred from the claim text.