THREE-DIMENSIONAL MICROSCOPIC MAGNETIC RESONANCE ANGIOGRAPHY

• US 20090274352A1
• Filed: 05/01/2009
• Published: 11/05/2009
• Est. Priority Date: 05/02/2008
• Status: Active Grant

• Current Assignee: Academia Sinica (Government of The Republic of China)
• Original Assignee: Academia Sinica (Government of The Republic of China)
• Inventors: LIN, Chien-Yuan, CHANG, Chen, CHEN, Jyh-Horng
• Granted Patent: US 8,233,685 B2
• Time in Patent Office: Days
• US Class Current: 382/130
• 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 33/5608 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 33/5635 Angiography, e.g. contrast-enhanced angiography [CE-MRA] or time-of-flight angiography [TOF-MRA]

Abstract

A method comprises performing a first T2-weighted imaging (T2WI) on a subject; injecting the subject with a contrast agent after performing the first T2WI; and waiting a predetermined period of time before performing a second T2WI on the subject. The first T2WI and second T2WI are then co-registered. The co-registered first T2WI and co-registered second T2WI are then trimmed. A ΔR₂ map is then determined based on each pixel of the trimmed first T2WI and corresponding pixels of the trimmed second T2WI. A three-dimensional map is constructed based on the ΔR₂ map.

Claims

1. A method comprising:

performing a first T2-weighted imaging (T2WI) on a subject;

injecting said subject with a contrast agent after performing said first T2WI;

waiting a predetermined period of time before performing a second T2WI on said subject;

co-registering said first T2WI and said second T2WI;

trimming said co-registered first T2WI and said co-registered second T2WI;

determining a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI; and

constructing a three-dimensional (3D) map based on said Δ

R₂ map.

2. The method claim 1 further comprising generating 3D images of vessels of said subject based on said 3D map without sensitivity to flow of matter through said vessels, wherein said vessels include at least one of veins, sinuses, arterioles, venules, and capillaries.

3. The method of claim 1 further comprising rendering in-vivo microvascular architecture and generating microvascular fluid volume data for vessels of said subject based on said 3D map, wherein said vessels include at least one of veins, sinuses, arterioles, venules, and capillaries.

4. A method comprising:

generating three-dimensional (3D) images of vessels including microvessels of a subject without sensitivity to flow of matter through said vessels; and

generating in-vivo microvascular architecture data and microvascular fluid volume data for said vessels based on said 3D images.

5. The method of claim 4 further comprising generating said 3D images based on steady-state 3D Δ

R₂-based microscopic magnetic resonance angiography (3DΔ

R₂-mMRA) that includes;

performing a first T2-weighted imaging (T2WI) on said subject;

injecting said subject with a contrast agent after performing said first T2WI;

waiting a predetermined period of time before performing a second T2WI on said subject;

co-registering said first T2WI and said second T2WI;

trimming said co-registered first T2WI and said co-registered second T2WI;

determining a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI;

constructing a 3D map based on said Δ

R₂ map; and

generating said 3D images based on said 3D map.

6. The method of claim 4 further comprising generating said 3D images of said vessels that include at least one of veins, sinuses, arterioles, venules, and capillaries.

7. The method claim 4 further comprising rendering at least one of intracortical and subcortical microvasculature of said vessels in said 3D images.

8. The method of claim 4 further comprising rendering said microvascular architecture in said 3D images and generating said microvascular fluid volume data using at least one of maximum intensity projection and volume rendering.

9. The method of claim 4 further comprising identifying at least one of intracortical arterioles and intracortical venules with slow-moving spins in said subject from said 3D images.

10. The method of claim 4 further comprising generating said 3D images based on a magnetic susceptibility effect that is insensitive to flow-related artifacts including at least one of turbulent and pulsatile flows through said vessels.

11. The method of claim 4 further comprising generating said 3D images without sensitivity to a geometric distortion caused by magnetic field inhomogeneities at an air-tissue interface in said subject.

12. The method of claim 4 further comprising generating said 3D images without sensitivity to changes in magnetic susceptibility caused by discontinuities in tissue properties in said subject.

13. The method of claim 4 further comprising revealing in-vivo microangiographic processes in ischemia in said subject based on said 3D images.

14. The method of claim 4 further comprising tracing angiogenesis in a lesion area in said subject in presence of tissue necrosis in said lesion area based on said 3D images.

15. A method comprising:

rendering three dimensional (3D) images of microvasculature of a tumor in a subject using steady-state 3D Δ

R₂-based microscopic magnetic resonance angiography (3DΔ

R₂-mMRA); and

measuring hemodynamic parameters including at least one of blood volume, blood flow, and permeability of vessels associated with said tumor using said 3DΔ

R₂-mMRA.

16. The method of claim 15 further comprising determining functional and structural changes in said microvasculature based on said 3D images and said hemodynamic parameters.

17. The method of claim 15, wherein said 3DΔ

R₂-mMRA includes;

performing a first T2-weighted imaging (T2WI) on said subject;

injecting said subject with a contrast agent after performing said first T2WI;

waiting a predetermined period of time before performing a second T2WI on said subject;

co-registering said first T2WI and said second T2WI;

trimming said co-registered first T2WI and said co-registered second T2WI;

determining a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI;

constructing a 3D map based on said Δ

R₂ map; and

generating said 3D images based on said 3D map.

18. The method claim 15 further comprising generating said 3D images and measuring said hemodynamic parameters based on said 3D map.

19. A system comprising:

a T2-weighted imaging (T2WI) module that performs a first T2-weighted imaging (T2WI) on a subject and that performs a second T2WI on said subject after said subject is injected with a contrast agent;

a co-registering module that co-registers said first T2WI and said second T2WI and that generates co-registered first T2WI and co-registered second T2WI;

a trimming module that trims said co-registered first T2WI and said co-registered second T2WI and that generates trimmed first T2WI and trimmed second T2WI;

a Δ

R₂ mapping module that generates a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI; and

a 3D mapping module that generates a three-dimensional (3D) map based on said Δ

R₂ map.

20. The system claim 19 further comprising a 3D imaging module that generates 3D images of vessels of said subject based on said 3D map without sensitivity to flow of matter through said vessels, wherein said 3D images render in-vivo microvascular architecture of said vessels, and wherein said vessels include at least one of veins, sinuses, arterioles, venules, and capillaries.

21. The system of claim 19 further comprising a hemodynamic data module that generates hemodynamic data including microvascular fluid volume data for vessels of said subject based on said 3D map, wherein said vessels include at least one of veins, sinuses, arterioles, venules, and capillaries.

22. A system comprising:

a three-dimensional (3D) imaging module that generates 3D images of vessels of a subject without sensitivity to flow of matter through said vessels, wherein said 3D images render in-vivo microvascular architecture of said vessels, where said vessels include at least one of veins, sinuses, arterioles, venules, and capillaries; and

a hemodynamic data module that generates hemodynamic data including microvascular fluid volume data for said vessels based on said 3D images.

23. The system of claim 22, wherein said 3D imaging module generates said 3D images based on steady-state 3D Δ

R₂-based microscopic magnetic resonance angiography (3DΔ

R₂-mMRA), and wherein said hemodynamic data module generates said hemodynamic data based on said 3DΔ

R₂-mMRA.

24. The system of claim 22 further comprising:

a T2-weighted imaging (T2WI) module that performs a first T2-weighted imaging (T2WI) on said subject and that performs a second T2WI on said subject after said subject is injected with a contrast agent;

a co-registering module that co-registers said first T2WI and said second T2WI and that generates co-registered first T2WI and co-registered second T2WI;

a trimming module that trims said co-registered first T2WI and said co-registered second T2WI and that generates trimmed first T2WI and trimmed second T2WI;

a Δ

R₂ mapping module that generates a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI; and

a 3D mapping module that generates a 3D map based on said Δ

R₂ map.

25. The system of claim 23, wherein said 3D imaging module generates said 3D images based on said 3D map, and wherein said hemodynamic data module generates said hemodynamic data based on said 3D map.

26. The system of claim 22 further comprising a rendition control module that renders said microvascular architecture and said microvascular fluid volume data in said 3D images using at least one of maximum intensity projection and volume rendering.

27. The system of claim 22 further comprising:

a data acquisition module that uses an acquisition matrix and that acquires data on said subject from a magnetic resonance apparatus; and

a control module that controls resolution of said 3D images by controlling at least one of a size of said acquisition matrix, an imaging sensitivity of said magnetic resonance apparatus, a field of view of said magnetic resonance apparatus, and a refocus pulse of said magnetic resonance apparatus.

28. The system claim 22, wherein said 3D imaging module renders at least one of intracortical and subcortical microvasculature of said vessels in said 3D images.

29. The system of claim 22, wherein said 3D imaging module generates renditions of at least one of intracortical arterioles and intracortical venules with slow-moving spins in said subject.

30. The system of claim 22, wherein said 3D imaging module generates said 3D images based on a magnetic susceptibility effect that is insensitive to flow-related artifacts including at least one of turbulent and pulsatile flows through said vessels.

31. The system of claim 22, wherein said 3D imaging module generates said 3D images without sensitivity to a geometric distortion caused by magnetic field inhomogeneities at an air-tissue interface in said subject.

32. The system of claim 22, wherein said 3D imaging module generates said 3D images without sensitivity to changes in magnetic susceptibility caused by discontinuities in tissue properties in said subject.

33. The system of claim 22, wherein said 3D imaging module generates said 3D images that reveal in-vivo microangiographic processes in ischemia in said subject.

34. The system of claim 22, wherein said 3D imaging module generates said 3D images that indicate angiogenesis in a lesion area in said subject in presence of tissue necrosis in said lesion area.

35. A system comprising:

a three dimensional (3D) imaging module that renders 3D images of microvasculature of a tumor in a subject using steady-state 3D Δ

R₂-based microscopic magnetic resonance angiography (3DΔ

R₂-mMRA); and

a hemodynamic data module that measures hemodynamic parameters including at least one of blood volume, blood flow, and permeability of vessels associated with said tumor using said 3DΔ

R₂-mMRA.

36. The system of claim 35 further comprising:

a T2-weighted imaging (T2WI) module that performs a first T2-weighted imaging (T2WI) on said subject and that performs a second T2WI on said subject after said subject is injected with a contrast agent;

a co-registering module that co-registers said first T2WI and said second T2WI and that generates co-registered first T2WI and co-registered second T2WI;

a trimming module that trims said co-registered first T2WI and said co-registered second T2WI and that generates trimmed first T2WI and trimmed second T2WI;

a Δ

R₂ mapping module that generates a Δ

R₂ map based on each pixel of said trimmed first T2WI and corresponding pixels of said trimmed second T2WI; and

a 3D mapping module that generates a 3D map based on said Δ

R₂ map.

37. The system of claim 36, wherein said 3D imaging module generates said 3D images based on said 3D map, and wherein said hemodynamic data module generates said hemodynamic data based on said 3D map.