Motion sensitized and motion suppressed imaging using dante prepared pulse trains

Patent metadata

Field	Value
Publication number	US-9759797-B2
Application number	US-201313815755-A
Country	US
Kind code	B2
Filing date	Mar 14, 2013
Priority date	Mar 20, 2012
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Systems and methods for motion sensitized and motion suppressed quantitative imaging of a subject are provided as a train of interlaced radio frequency (RF) and magnetic field gradient pulses. Non-selective Delay Alternating with Nutation for Tailored Excitation (DANTE) pulse trains may be used in combination with gradient pulses and short repetition times as motion-sensitive preparation modules. In one or more embodiments, the systems and methods may use a train of low flip angle radio frequency (RF) pulses in combination with a blipped field gradient pulse between each RF pulse, repeated regularly. While the longitudinal magnetization of static tissue is mostly preserved, moving spins are largely (or fully) suppressed since they fail to establish transverse steady state due to a spoiling effect caused by flow along the applied gradient. The present systems and methods can be incorporated into any existing imaging readout for applications in vessel wall imaging, angiography, high resolution structural MRI, and also functional MRI.

First claim

What is claimed:

1. A method for providing quantitative magnetic resonance imaging comprising:
A. Providing a magnetic resonance imaging (MRI) device;
B. Using the magnetic resonance image device in association with a subject to generate a train of radio frequency (RF) pulse modules in combination with field gradient pulses interlaced in between the RF pulse modules, wherein the train of RF pulse modules constitutes a non-selective unbalanced steady state precession as a moving spin suppression preparation;
C. Repeating the train of pulses to drive static tissue in the subject into steady state in order to preserve the magnetization of the static tissue while suppressing moving spins in moving tissue or fluid in the subject; and
D. Acquiring an image of the static tissue signal having a suppressed signal from the moving tissue and/or fluids.

2. The method of claim 1 , wherein the train of pulses is regularly repeated for a period of time sufficient to drive the static tissue into a steady state.

3. The method of claim 1 , wherein the train of radio frequency (RF) pulse modules comprises low flip angle RF pulses having a flip angle of about 45° or below.

4. The method of claim 1 , wherein the train of radio frequency (RF) pulse modules comprises non-selective Delay Alternating with Nutation for Tailored Excitation (DANTE) pulse modules.

5. The method of claim 1 , wherein the field gradient pulses are blipped magnetic field gradient pulses with gradient amplitudes varying from 0 to the maximum value provided by a scanner of the MRI device.

6. The method of claim 1 , wherein the field gradient pulses are interlaced in a regular pattern between the RF pulse modules.

7. The method of claim 6 , wherein the field gradient pulses are interlaced between each RF pulse module in the train.

8. The method of claim 1 , wherein signal from moving spins, is simultaneously suppressed while substantially preserving the signal from static tissue signal for MR imaging readout acquisitions.

9. The method of claim 1 , wherein physiological noise, influence of motion and flow artefacts are suppressed.

10. The method of claim 1 , wherein the imaging is employed for an application selected from the group consisting of:
a) Flowing spin suppression in 2D or 3D Black Blood (BB) magnetic resonance imaging (MRI),
b) CSF flow quantification and suppression, allowing (e.g.) accurate multiple sclerosis evaluation or diagnosis in spinal cord (structure imaging) or physiological noise elimination in spinal cord neuroscience studies (spinal cord functional MRI),
c) digital subtraction mode allowing smaller vessels to be resolved due to superior static signal cancellation,
d) functional MRI to achieve intravascular blood suppressed blood oxygen level dependent (BOLD) signal for localization and quantification of neural activity,
e) blood suppressed MRI intervention techniques,
f) quantitative measurement of T 1 , T 2 and proton density in BB images of atherosclerotic plaques in arteries of the brain or in the aorta, and
g) perfusion MRI measurement for research and clinical applications.

11. The method of claim 1 , wherein the time interval between the end of one RF pulse module and the beginning of the next RF pulse module is sufficiently long to allow longitudinal magnetization to largely recover before a subsequent RF pulse module is applied.

12. The method of claim 1 , wherein the number of pulses applied in the RF pulse modules ranges from 10-100, and the inter-pulse repeat time of RF pulses within the RF pulse modules is less than 5 ms.

13. A system, comprising
a magnetic resonance imaging (MRI) device;
at least one computing device;
at least one application executable in the at least one computing device, the at least one application comprising logic that:
A. generates a train of radio frequency (RF) pulse modules in combination with field gradient pulses interlaced in between the RF pulse modules, in association with the magnetic resonance image device and a subject wherein the train of RF pulse modules constitutes a non-selective unbalanced steady state precession as a moving spin suppression preparation;
B. repeats the train of pulses to drive static tissue in the subject into steady state in order to preserve the magnetization of the static tissue while suppressing moving spins in moving tissue or fluid in the subject; and
C. Acquires an image of the static tissue signal having a suppressed signal from the moving tissue and/or fluids.

14. The system of claim 13 , wherein the train of radio frequency (RF) pulse modules comprises low flip angle RF pulses having a flip angle of about 45° or below.

15. The system of claim 13 , wherein the train of radio frequency (RF) pulse modules comprises non-selective Delay Alternating with Nutation for Tailored Excitation (DANTE) pulse modules.

16. The system of claim 13 , wherein the field gradient pulses are blipped magnetic field gradient pulses with gradient amplitudes varying from 0 to the maximum value provided by a scanner of the MRI device.

17. The system of claim 13 , wherein the field gradient pulses are interlaced in a regular pattern between the RF pulse modules.

18. The system of claim 17 , wherein the field gradient pulses are interlaced between each RF pulse module in the train of pulses.

19. The system of claim 13 , wherein signal from moving spins, is simultaneously suppressed while substantially preserving the signal from static tissue signal for MR imaging readout acquisitions.

20. The system of claim 13 , wherein physiological noise, influence of motion and flow artefacts are suppressed.

Assignees

• Isis Innovation
• Univ Oxford Innovation Ltd

Inventors

• Li Linqing
• Jezzard Peter

Classifications

• G01R33/5607

  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 title

• G01R33/56509 Primary

  due to motion, displacement or flow, e.g. gradient moment nulling (G01R33/567 takes precedence) · CPC title

• G01R33/5613

  Generating steady state signals, e.g. low flip angle sequences [FLASH] · CPC title

• G01R33/5635

  Angiography, e.g. contrast-enhanced angiography [CE-MRA] or time-of-flight angiography [TOF-MRA] · CPC title

• G01R33/4835

  of multiple slices · CPC title