Magnetic resonance imaging method and apparatus based on two-dimensional fast spin echo

Patent metadata

Field	Value
Publication number	US-12386003-B2
Application number	US-201916729799-A
Country	US
Kind code	B2
Filing date	Dec 30, 2019
Priority date	Dec 28, 2018
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

In a magnetic resonance imaging method, a first adjustment parameter is determined for presetting an initial contrast of a magnetic resonance image; a second adjustment parameter is determined for obtaining an optimized contrast of the magnetic resonance image and a specified data acquisition time of a blade artifact correction sequence; an optimized echo signal evolution curve is determined according to the first adjustment parameter and the second adjustment parameter; an actual variable flip angle train is calculated according to the optimized echo signal evolution curve; and the actual variable flip angle train is applied to a two-dimensional fast spin echo sequence, and the blade artifact correction sequence corresponding to the second adjustment parameter is used to acquire magnetic resonance signals and enable the magnetic resonance image to satisfy the optimized contrast.

First claim

The invention claimed is:

1. A magnetic resonance imaging method based on a two-dimensional fast spin echo sequence, which uses a Balanced Steady State Free Precession Line Acquisition with Undersampling (BLADE) artifact correction sequence to perform data acquisition of magnetic resonance signals, the method comprising:
determining a first adjustment parameter to preset an initial contrast of a magnetic resonance image;
after the determining the first adjustment parameter to preset the initial contrast of the magnetic resonance image, (i) calculating an initial predetermined echo signal evolution curve based on the first adjustment parameter, and (ii) calculating an initial variable flip angle train based on the initial predetermined echo signal evolution curve;
determining a second adjustment parameter to obtain an optimized contrast of the magnetic resonance image and a specified data acquisition time of the BLADE artifact correction sequence;
determining an optimized echo signal evolution curve based on the first adjustment parameter and the second adjustment parameter;
calculating an actual variable flip angle train based on the optimized echo signal evolution curve; and
applying the actual variable flip angle train to the two-dimensional fast spin echo sequence, and using the BLADE artifact correction sequence corresponding to the second adjustment parameter to acquire magnetic resonance signals and enable the magnetic resonance image to satisfy the optimized contrast.

2. The magnetic resonance imaging method according to claim 1 , wherein the second adjustment parameter comprises an echo spacing and/or an echo train length.

3. The magnetic resonance imaging method according to claim 1 , wherein the calculating the actual variable flip angle train comprises:
reckoning optimized variable flip angles based on the optimized echo signal evolution curve;
calculating a calculated echo signal evolution curve based on the optimized variable flip angles; and
comparing the calculated echo signal evolution curve with the optimized echo signal evolution curve and selectively using, based on a result of the comparison satisfying a predetermined criterion, the optimized variable flip angles as the actual variable flip angle train.

4. The magnetic resonance imaging method according to claim 3 , wherein the optimized variable flip angles are used as the actual variable flip angle train when a difference between the calculated echo signal evolution curve and the optimized echo signal evolution curve satisfies a specified requirement in accordance with the predetermined criterion.

5. The magnetic resonance imaging method based on two-dimensional fast spin echo according to claim 1 , wherein the first adjustment parameter comprises one of the following preset variable flip angle modes:
longitudinal magnetization vector relaxation time T1-weighted,
proton density PD-weighted, or
transverse magnetization vector relaxation time T2-weighted.

6. A non-transitory computer-readable storage medium with an executable program stored thereon, that when executed, instructs a processor to perform the method of claim 1 .

7. A non-transitory computer program product having a computer program which is directly loadable into a memory of a controller of a magnetic resonance device that, when executed by the controller, causes the magnetic resonance device to perform the method as claimed in claim 1 .

8. The magnetic resonance imaging method according to claim 1 , wherein determining the second adjustment parameter comprises determining an increased echo train length that increases a BLADE width to thereby reduce a data acquisition time of the BLADE artifact correction sequence.

9. The magnetic resonance imaging method according to claim 8 , wherein the reduction in data acquisition time of the BLADE artifact correction sequence enables the magnetic resonance image to satisfy the optimized contrast so as to eliminate artifacts.

10. The magnetic resonance imaging method according to claim 1 , wherein the first adjustment parameter comprises one of a longitudinal magnetization vector relaxation time T1-weighted preset variable flip angle mode, a proton density PD-weighted preset variable flip angle mode, or a transverse magnetization vector relaxation time T2-weighted preset variable flip angle mode, and
wherein the second adjustment parameter comprises an echo spacing and/or an echo train length.

11. The magnetic resonance imaging method according to claim 1 , wherein the calculating the actual variable flip angle train comprises:
calculating the actual variable flip angle based on the optimized echo signal evolution curve by selecting from among (i) an initial variable flip angle train that is calculated based upon a predetermined echo signal evolution curve that is based on the first adjustment parameter, or (ii) an optimized flip angle train that is calculated based on the optimized echo signal evolution curve.

12. The magnetic resonance imaging method according to claim 1 , wherein the actual variable flip angle train comprises variable flip angles introduced into the BLADE artifact correction sequence to control attenuation of transverse magnetization vector relaxation time T2 by adjusting a value of the flip angle as BLADE width is increased.

13. The magnetic resonance imaging method according to claim 12 , wherein the variable flip angles of the actual variable flip angle train increase an echo train length while reducing an effect of attenuation of the transverse magnetization vector relaxation time T2.

14. A magnetic resonance imaging apparatus using a two-dimensional fast spin echo sequence, which uses a Balanced Steady State Free Precession Line Acquisition with Undersampling (BLADE) artifact correction sequence to perform data acquisition of magnetic resonance signal, the apparatus comprising:
a first adjustment parameter determiner configured to determine a first adjustment parameter to preset an initial contrast of a magnetic resonance image;
a second adjustment parameter determiner configured to determine a second adjustment parameter to obtain an optimized contrast of the magnetic resonance image and a specified data acquisition time of the BLADE artifact correction sequence;
an echo signal evolution curve determiner configured to calculate an initial predetermined echo signal evolution curve based on the first adjustment parameter, and to determine an optimized echo signal evolution curve based on the first adjustment parameter and the second adjustment parameter;
a variable flip angle train determiner configured to calculate an initial variable flip angle train based on the initial predetermined echo signal evolution curve, and to calculate an actual variable flip angle train based on to the optimized echo signal evolution curve; and
a magnetic resonance imaging scanner configured to:
apply the actual variable flip angle to the two-dimensional fast spin echo sequence; and
use the BLADE artifact correction sequence corresponding to the second adjustment parameter to acquire magnetic resonance signals and enable the magnetic resonance image to satisfy the optimized contrast.

15. The magnetic resonance imaging apparatus according to claim 14 , wherein the second adjustment parameter determiner determines an echo spacing and/or an echo train length for obtaining the optimized contrast of the magnetic resonance image, and an echo train length for obtaining the specified data acquisition time of the BLADE artifact correction sequence.

16. The magnetic resonance imaging apparatus according to claim 1

Assignees

• Siemens Healthcare Gmbh
• Siemens Healthineers Ag

Inventors

• Wang yu yu
• Weng De He
• Zhou Kun
• Zhang Le

Classifications

• G01R33/543 Primary

  Control of the operation of the MR system, e.g. setting of acquisition parameters prior to or during MR data acquisition, dynamic shimming, use of one or more scout images for scan plane prescription (G01R33/546 takes precedence) · CPC title

• G01R33/5617

  using RF refocusing, e.g. RARE · CPC title

• G01R33/4824

  using a non-Cartesian trajectory · CPC title

• G01R33/5615

  Echo train techniques involving acquiring plural, differently encoded, echo signals after one RF excitation, e.g. using gradient refocusing in echo planar imaging [EPI], RF refocusing in rapid acquisition with relaxation enhancement [RARE] or using both RF and gradient refocusing in gradient and spin echo imaging [GRASE] · CPC title

• G01R33/50

  based on the determination of relaxation times {, e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences} · CPC title