Method and apparatus for magnetic resonance imaging of arteries using a magnetic resonance contrast agent

• US 20030163036A1
• Filed: 02/27/2003
• Published: 08/28/2003
• Est. Priority Date: 06/07/1993
• Status: Active Grant

• Current Assignee: Martin R. Prince
• Original Assignee: Martin R. Prince
• Inventors: Prince, Martin R.
• Granted Patent: US 6,754,521 B2
• Time in Patent Office: Days
• US Class Current: 600/420
• CPC Class Codes: A61B 5/201 Assessing renal or kidney functions
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61B 5/416 the spleen
• CPC Class Codes: A61K 49/18 characterised by a special physical form, e.g. emulsions, microcapsules, liposomes
• CPC Class Codes: A61M 5/007 for contrast media
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/16827 controlling delivery of multiple fluids, e.g. sequencing, mixing or via separate flow-paths infusion of multiple fluids without using a controller A61M5/1407
• CPC Class Codes: G01R 33/281 Means for the use of in vitro contrast agents G01R33/282 takes precedence; involving use of a contrast agent in MR imaging G01R33/5601; in vivo contrast agents A61K49/0002
• 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 33/5619 by temporal sharing of data, e.g. keyhole, block regional interpolation scheme for k-Space [BRISK]
• CPC Class Codes: G01R 33/563 of moving material, e.g. flow contrast angiography
• CPC Class Codes: G01R 33/56308 Characterization of motion or flow; Dynamic imaging
• CPC Class Codes: G01R 33/5635 Angiography, e.g. contrast-enhanced angiography [CE-MRA] or time-of-flight angiography [TOF-MRA]

Abstract

The present invention is a technique and apparatus for providing preferential enhancement of an artery of interest relative to adjacent veins and background tissue by correlating the collection of a predetermined portion of data of a magnetic resonance contrast image during the arterial phase of the magnetic resonance contrast enhancement. The arterial phase of the contrast enhancement may be described as a period of a maximum, substantially elevated, or elevated contrast concentration in the artery of interest relative to adjacent veins.

The present invention includes a detection system for monitoring and detecting the arrival of the contrast agent in the artery and tissues of interest. When the concentration of contrast agent in the artery of the region of interest is maximum, substantially elevated or elevated (e.g., about 20-50% greater than the response of the region of interest to a series of magnetic resonance pulses before administration of a magnetic resonance contrast agent), a predetermined portion of the magnetic resonance image data (e.g., data which is representative of the center of k-space) may be acquired. Thus, the present invention facilitates synchronization between collecting the central portion of k-space image data with the arterial phase of contrast enhancement. The center of k-space corresponds to the lowest spatial frequency data which dominates image contrast.

Claims

1. A method of imaging an artery of a patient using magnetic resonance imaging, comprising,

detecting an elevated concentration of magnetic resonance contrast agent in the artery;

and

imaging at least a portion of the artery including collecting image data which is representative of the center of k-space after detecting the elevated concentration of magnetic resonance contrast agent in the artery.

2. The method of claim 1 wherein the step of imaging at least a portion of the artery further includes collecting image data which is representative of the center of k-space when a concentration of the contrast agent in the artery is substantially higher than a concentration of the contrast agent in veins adjacent to the artery.

3. The method of claim 1 wherein the step of imaging at least a portion of the artery includes collecting image data which is representative of the center of k-space when the concentration of the contrast agent in the artery is greater than a predetermined concentration.

4. The method of claim 1 wherein the step of imaging at least a portion of the artery includes collecting image data which is representative of the center of k-space substantially at the beginning of an imaging sequence.

5. The method of claim 4 wherein the imaging sequence is a 3D imaging sequence.

6. The method of claim 1 wherein the step of detecting an elevated concentration of magnetic resonance contrast agent in the artery further includes measuring a base line signal which is representative of a response of the artery to at least one magnetic resonance radio frequency pulse prior to administering the magnetic resonance contrast agent to the patient.

7. The method of claim 6 wherein the step of detecting an elevated concentration of magnetic resonance contrast agent in the artery includes the step of monitoring the artery after administering the contrast agent to the patient to detect the arrival of the contrast agent in the artery.

8. The method of claim 7 wherein the step of detecting an elevated concentration of contrast in the artery further includes the step of detecting a change in the response of the artery to at least one magnetic resonance radio frequency pulse.

9. The method of claim 8 wherein the change in the response of the artery to at least one radio frequency pulse includes a change in a maximum amplitude of a responsive RF signal or a change in the shape of a responsive RF signal.

10. The method of claim 7 wherein the step of imaging at least a portion of the artery of interest includes collecting image data which is representative of the center of k-space substantially at the beginning of an imaging sequence and while the concentration of the contrast agent in the artery is substantially elevated.

11. The method of claim 10 wherein the imaging sequence is a gradient echo imaging sequence.

12. The method of claim 10 wherein the imaging sequence is a 3D gradient echo imaging sequence.

13. A method of imaging an artery in a region of interest of a patient using magnetic resonance imaging, comprising,

detecting a predetermined concentration of magnetic resonance contrast agent in the artery;

and

imaging at least a portion of the artery including collecting image data which is representative of the center of k-space after detecting the predetermined concentration of the contrast agent in the artery and while the concentration in the artery is higher than a concentration of the contrast agent in veins adjacent to the artery.

14. The method of claim 13 wherein the step of detecting a predetermined concentration of magnetic resonance contrast agent in the artery detects the arrival of the contrast in the artery.

15. The method of claim 14 wherein the step of imaging at least a portion of the artery of interest includes collecting image data which is representative of the center of k-space substantially at the beginning of a 3D imaging sequence.

16. The method of claim 13 wherein the step of imaging at least a portion of the artery further includes collecting image data which is representative of the center of k-space while the concentration in the artery is substantially higher than a concentration of the contrast agent in veins adjacent to the artery.

17. The method of claim 16 wherein the step of detecting magnetic resonance contrast agent in the artery includes detecting a substantially elevated concentration of magnetic resonance contrast agent in the artery and the step of imaging at least a portion of the artery includes collecting image data which is representative of the center of k-space after detecting the substantially elevated concentration of magnetic resonance contrast agent in the artery.

18. The method of claim 17 further including the step of administering the magnetic resonance contrast agent to the patient in a bolus type injection and wherein the step of imaging at least a portion of the artery of interest includes collecting image data which is representative of the center of k-space substantially at the beginning of a 3D imaging sequence.

19. An apparatus for imaging an artery in a region of interest of a patient using magnetic resonance imaging, comprising,

detecting means for detecting a predetermined concentration of magnetic resonance contrast agent in the artery and, in response thereto, for generating an imaging initiation signal;

and

imaging means, coupled to the detecting means, for collecting image data which is representative of the center of k-space in response to the imaging initiation signal.

20. The apparatus of claim 19 wherein the imaging means collects the image data which is representative of the center of k-space substantially at the beginning of a 3D imaging sequence.

21. The apparatus of claim 19 wherein the detecting means generates the imaging initiation signal when the concentration of the contrast agent in the artery is substantially elevated.

22. An apparatus for imaging an artery of a patient using magnetic resonance imaging and a magnetic resonance imaging contrast agent, comprising,

detecting means for generating an imaging initiation signal in response to detecting the magnetic resonance imaging contrast agent in the artery;

and

imaging means, coupled to the detecting means, for collecting image data which is representative of the center of k-space in response to the imaging initiation signal.

23. The apparatus of claim 22 wherein the imaging means collects the image data which is representative of the center of k-space substantially at the beginning of a 3D imaging sequence.

24. The apparatus of claim 22 wherein the imaging means collects image data which is representative of a periphery of k-space after collecting image data which is representative of the center of k-space.