SYSTEM AND METHOD FOR REDUCING PARTIAL VOLUMING ARTIFACTS IN QUANTITATIVE MYOCARDIAL TISSUE CHARACTERIZATION

• US 20180067184A1
• Filed: 09/05/2017
• Published: 03/08/2018
• Est. Priority Date: 09/08/2016
• Status: Active Grant

• Current Assignee: Regents of The University of Minnesota (University of Minnesota)
• Original Assignee: Regents of The University of Minnesota (University of Minnesota)
• Inventors: Weingartner, Sebastian, Akcakaya, Mehmet
• Granted Patent: US 10,451,700 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 33/50 based on the determination of relaxation times , e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences
• CPC Class Codes: G01R 33/5602 by filtering or weighting based on different relaxation times within the sample, e.g. T1 weighting using an inversion pulse
• CPC Class Codes: G01R 33/5607 by reducing the NMR signal of a particular spin species, e.g. of a chemical species for fat suppression, or of a moving spin species for black-blood imaging
• CPC Class Codes: G01R 33/5608 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 Class Codes: G01R 33/5614 using a fully balanced steady-state free precession [bSSFP] pulse sequence, e.g. trueFISP
• CPC Class Codes: G01R 33/56545 caused by finite or discrete sampling, e.g. Gibbs ringing, truncation artefacts, phase aliasing artefacts

Abstract

A system and method for obtaining magnetic resonance images are provided. The system is programmed to control the RF system to apply a saturation pulse at a reference frequency that saturates a selected labile spin species of the subject. The system is programmed to control the RF system to apply an inversion pulse after a variable delay. The system is programmed to control the RF system and the plurality of gradient coils to apply a motion sensitized driven equilibrium (MSDE) preparation pulse. The system is programmed to control the plurality of gradient coils to read imaging data during an acquisition time period. The system is programmed to reconstruct a T₁ mapping image of the subject with black-blood contrast.

Claims

1. A magnetic resonance imaging (MRI) system comprising:

a magnet system configured to generate a polarizing magnetic field about at least a region of interest (ROI) in a subject arranged in the MRI system;

a plurality of gradient coils configured to apply a gradient field to the polarizing magnetic field;

a radio frequency (RF) system configured to apply an excitation field to the subject and acquire MR image data from the ROI;

a computer system programmed to;

control the RF system to apply a saturation pulse at a reference frequency that saturates a selected labile spin species of the subject;

control the RF system to apply an inversion pulse after a variable delay;

control the RF system and the plurality of gradient coils to apply a blood suppression preparation pulse;

control the plurality of gradient coils to read imaging data during an acquisition time period; and

reconstruct a T1 mapping image of the subject with black-blood contrast.

2. The MRI system of claim 1 wherein the blood suppression preparation pulse includes a motion sensitized driven equilibrium (MSDE) preparation pulse.

3. The MRI system of claim 2 wherein the computer system is programmed to perform a balanced Steady-State Free-Precession (bSSFP) imaging readout after applying the MSDE preparation pulse.

4. The MRI system of claim 3 wherein the MSDE preparation pulse comprises a non-selective 90°

tip-down pulse, a series of one or more 180°

refocusing pulses, and a final 90°

tip-up pulse.

5. The MRI system of claim 2 wherein the MSDE preparation pulse has an echo time between 11 ms and 15 ms.

6. The MRI system of claim 2 wherein the MSDE preparation pulse comprises a rectangular 90°

hard-pulses for tip-down and tip-up and a single 180°

MLEV refocusing pulse.

7. The MRI system of claim 2 wherein the MSDE preparation pulse comprises a rectangular 90°

hard-pulse for tip-down, an adiabatic 180°

BIREF1 refocusing pulse and a composite (360°

-270°

) tip-up pulse.

8. The MRI system of claim 2 wherein the MSDE preparation pulse comprises a 0°

degree three compartment BIR4 pulse, wherein the MSDE gradients are inserted symmetrically between the compartments.

9. The MRI system of claim 2 wherein the computer system is programmed to perform imaging at late end-diastole to accommodate the MSDE preparation well within the end-diastolic quiescence.

10. The MRI system of claim 1 wherein the blood suppression preparation pulse employs a pulse train of velocity and shear sensitizing pulses to suppress blood signal.

11. A method comprising:

controlling, by a magnetic resonance imaging (MRI) system, a radio frequency (RF) system to apply a saturation pulse at a reference frequency that saturates a selected labile spin species of the subject;

controlling the RF system to apply an inversion pulse after a variable delay;

controlling the RF system and the plurality of gradient coils to apply a blood suppression preparation pulse;

controlling the plurality of gradient coils to read imaging data during an acquisition time period; and

reconstructing a T1 mapping image of the subject with black-blood contrast.

12. The method of claim 11 wherein the blood suppression preparation pulse includes a motion sensitized driven equilibrium (MSDE) preparation pulse.

13. The method of claim 12 further comprising:

performing a balanced Steady-State Free-Precession (bSSFP) imaging readout after applying the MSDE preparation pulse.

14. The method of claim 13 wherein the MSDE preparation pulse comprises a non-selective 90°

tip-down pulse, a series of one or more 180°

refocusing pulses, and a final 90°

tip-up pulse.

15. The method of claim 12 wherein the MSDE preparation pulse has an echo time between 11 ms and 15 ms.

16. The method of claim 12 wherein the MSDE preparation pulse comprises a rectangular 90°

hard-pulses for tip-down and tip-up and a single 180°

MLEV refocusing pulse.

17. The method of claim 12 wherein the MSDE preparation pulse comprises a rectangular 90°

hard-pulse for tip-down, an adiabatic 180°

BIREF1 refocusing pulse and a composite (360°

-270°

) tip-up pulse.

18. The method of claim 12 wherein the MSDE preparation pulse comprises a 0°

degree three compartment BIR4 pulse, wherein the MSDE gradients are inserted symmetrically between the compartments.

19. The method of claim 12 further comprising:

performing imaging at late end-diastole to accommodate the MSDE preparation well within the end-diastolic quiescence.

20. The method of claim 11 further comprising:

applying the blood suppression preparation pulse that employs a pulse train of velocity and shear sensitizing pulses to suppress blood signal.