Accelerated acquisition of scan data by means of magnetic resonance

Patent metadata

Field	Value
Publication number	US-11963754-B2
Application number	US-202017038810-A
Country	US
Kind code	B2
Filing date	Sep 30, 2020
Priority date	Sep 30, 2019
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

Accelerated acquisition of scan data by means of magnetic resonance to enable short echo times so that scan data of substances can also be acquired with a transversal relaxation time.

First claim

The invention claimed is:

1. A method for producing scan data from an examination object, the method comprising:
reading out a k-space which corresponds to a mapping area of the scan data, by:
a) switching a constant gradient using a gradient field generator of a magnetic resonance system;
b) irradiating an RF excitation pulse using an RF transmitter/receiver of the magnetic resonance system;
c) following a time t 1 after the last irradiated RF excitation pulse, recording echo signals using the RF transmitter/receiver; and
d) storing the recorded echo signals as scan data along a trajectory in k-space predetermined by a strength of the switched gradient,
wherein the steps a) to d) are carried out repeatedly with various switched constant gradients, and the various gradients are switched in at least two phase encoding directions, and
wherein at least once following the time t 1 after the last switched RF excitation pulse, additional gradients with a modulating amplitude are switched in at least one direction which is oriented at right angles to a direction predetermined by the already switched constant gradients, until the k-space corresponding to the mapping area is read out in a first region which depends on the time t 1 ; and
e) reading out the k-space corresponding to the mapping area, which is not covered by the first region of the k-space and which comprises at least a k-space center, differently to that described by steps a) to d), and storing this scan data; and
reconstructing image data from the stored scan data of the k-space using a control facility of the magnetic resonance system.

2. The method as claimed in claim 1 , wherein the irradiated RF excitation pulses are irradiated after full strength of the constant gradients is reached.

3. The method as claimed in claim 1 , wherein the irradiated RF excitation pulses are non-slice-selective RF excitation pulses.

4. The method as claimed in claim 1 , wherein the scan data is read out in step e) as Cartesian scan data using a single point imaging method.

5. The method as claimed in claim 1 , wherein a modulation of the amplitude of an additional gradient is sinusoidal.

6. The method as claimed in claim 1 , wherein a maximum amplitude of the modulation of the additional gradients is selected as a function of a desired coverage of the k-space.

7. The method as claimed in claim 1 , wherein a portion of the first region is predetermined, in which additional gradients are switched while scan data is recorded.

8. The method as claimed in claim 7 , wherein the portion of the first region, in which additional gradients are switched while scan data is recorded as a function of a permissible noise development and/or is defined as a function of a desired maximum scan time for storing all scan data of the first region and/or as a function of a desired k-space coverage.

9. The method as claimed in claim 1 , wherein additional gradients are switched during recordings of scan data in an associated subregion of the first region or equally distributed in the first region.

10. The method as claimed in claim 1 , wherein additional gradients are switched during each recording of scan data.

11. The method as claimed in claim 1 , wherein the amplitude of an additional gradient is increased with increased distance from the k-space center.

12. A magnetic resonance system, comprising:
a magnet;
a gradient field generator;
a high frequency transmitter/receiver; and
a control facility with a high frequency transmitter/receiver controller with an additional gradient field generator,
wherein the control facility is embodied to carry out the method as claimed in claim 1 on the magnetic resonance system.

13. A non-transitory computer-readable medium comprising program code which when executed by a control facility of a magnetic resonance system performs the method of claim 1 .

Assignees

• Siemens Healthcare Gmbh
• Siemens Healthineers Ag

Inventors

• Dispenza Nadine
• Kartaeusch Ralf
• Paul Dominik
• Stich Manuel
• Zeller Mario

Classifications

• A61B5/062 Primary

  using magnetic field · CPC title

• G01R33/5608

  Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels (image data processing or generation, in general G06T) · CPC title

• G06T7/0012

  Biomedical image inspection · CPC title

• G06T2207/10088

  Magnetic resonance imaging [MRI] · CPC title

• G01R33/4816 Primary

  NMR imaging of samples with ultrashort relaxation times such as solid samples, e.g. MRI using ultrashort TE [UTE], single point imaging, constant time imaging · CPC title