BLOOD SIGNAL SUPPRESSED ENHANCED MAGNETIC RESONANCE IMAGING

• US 20110275928A1
• Filed: 05/03/2011
• Published: 11/10/2011
• Est. Priority Date: 05/05/2010
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Duke University
• Inventors: KIM, Raymond J.
• Granted Patent: US 9,149,203 B2
• Time in Patent Office: Days
• US Class Current: 600/413
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: G01R 33/5601 involving use of a contrast agent for contrast manipulation, e.g. a paramagnetic, super-paramagnetic, ferromagnetic or hyperpolarised contrast agent
• 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

Abstract

Methods for achieving suppression of blood pool signal to image contrast-enhanced organs and vascular walls using magnetic resonance (MR) imaging technology. After administration of e.g., an intravenous contrast agent, an RF pulse sequence is applied that includes a preparatory section designed to modify signal from organ tissue differently than blood pool signal, followed by an inversion RF pulse. MR signals are then allowed to evolve during a wait time that is sufficiently long to permit tissue species with dissimilar T1 relaxation times to separate in signal yet short enough so that blood signal has greater negative magnetization than other tissues of interest. MRI data is then acquired with phase sensitive reconstruction so that blood pool signal is suppressed compared with the tissues of interest.

Claims

1. A method of magnetic resonance imaging (MRI) with blood signal suppression comprising:

a. applying a pulse sequence having a preparatory section designed to modify signal from organ tissue differently than blood pool signal followed by an inversion RF pulse;

b. waiting for a period of time that is sufficiently long to allow organ tissue with dissimilar T1 relaxation times to have disparity in signal yet short enough so that blood signal has greater negative magnetization than the tissues of interest; and

c. acquiring MRI data from the region-of-interest with a phase sensitive reconstruction.

2. The method according to claim 1, wherein the preparatory section comprises one or more RF pulses that imparts weighting selected from the group consisting of T2 weighting, T1rho weighting, magnetization transfer weighting, and combinations thereof.

3. The method according to claim 2, wherein the preparatory section comprises one or more RF pulses that imparts T2 weighting.

4. The method according to claim 2, wherein the preparatory section comprises one or more RF pulses that imparts T1rho weighting.

5. The method according to claim 2, wherein the preparatory section comprises one or more RF pulses that imparts magnetization transfer weighting.

6. The method according to claim 1, wherein the inversion RF pulse comprises a flip angle between 90 and 180 degrees.

7. The method of claim 1 wherein the MIR data is acquired using a steady-state free precession (SSFP).

8. The method of claim 1 wherein MRI data is acquired using a gradient-recalled echo (GRE) readout.

9. The method of claim 1 wherein MRI data is acquired using a turbo-spin (TSE) readout.

10. The method of claim 1 wherein MRI data is acquired using an echo planar (EPI) readout.

11. The method of claim 1 wherein MRI data is acquired using a 2-dimensional readout.

12. The method of claim 1 wherein MRI data is acquired using a 3-dimensional readout.

13. The method of claim 1 wherein MRI data is acquired using a segmented acquisition so that data acquired for an image comes from at least two cycles of the sequence.

14. The method of claim 1 wherein MRI data is acquired using a single-shot acquisition so that data acquired for an image comes from once cycle of the sequence.

15. The method of claim 1 wherein MRI data is acquired using parallel imaging.

16. The method of claim 1 wherein MRI data is acquired using a Cartesian, radial, spiral or elliptical readout.

17. The method according to claim 1, wherein the MRI data is acquired using a technique comprising at least one of gradient-recalled echo (GRE) readout, turbo-spin echo (TSE readout, echo planar (EPI) readout, 2-dimensional readout, 3-dimensional readout, segmented acquisition so that data acquired for an image comes from at least two cycles of the sequence, a single-shot acquisition so that data acquired for an image comes from one cycle of the sequence, parallel imaging, Cartesian readout, radial readout, spiral readout, elliptical readout, and combinations thereof.

18. The method according to claim 1, wherein the readout is timed to occur during a specific phase of the electrocardiogram.

19. The method according to claim 1, wherein the phase sensitive reconstruction is based on obtaining a reference set of data.

20. The method according to claim 1, wherein the phase sensitive reconstruction is based on estimating the phase from local statistics or region growing approaches.

21. The method of claim 1 further including administering a contrast agent to the patient.