Diagnostic imaging systems and methods employing temporally resolved intensity tracing

• US 6,505,064 B1
• Filed: 08/22/2000
• Issued: 01/07/2003
• Est. Priority Date: 08/22/2000
• Status: Expired due to Term

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Margosian, Paul M., Liu, Kecheng
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): MANTIS MERCADER, ELENI M
• Application Number:
  US09/644,034
• Time in Patent Office: 868 Days
• Field of Search: 600/410, 600/420, 600/419, 600/407, 600/431, 600/425, 324/307, 324/309, 703/5, 382/210, 382/128, 382/285, 382/276, 345/424, 345/124, 128/922
• US Class Current: 600/420
• CPC Class Codes: G06T 11/206 Drawing of charts or graphs

Abstract

A diagnostic imaging system (100, 200) and method generates a plurality of temporally resolved volume image representations (130, 132, . . . , 134). A time course projection processor (140, 240) temporally collapses the volume image representations. A spatial projection processor (146, 246) performs a maximum or minimum intensity process along rays through voxels of a three-dimensional image representation. By sequentially temporally collapsing and maximum or minimum intensity projecting, in either order, the plurality of temporally resolved volume image representations is reduced to a two-dimensional temporally collapsed and spatially projected image representation (148, 248). In preferred embodiments, the present invention is directed to angiography, and more preferably to magnetic resonance angiography. In certain embodiments, time course information, such as blood flow rate information, vessel wall dynamics, contrast agent propagation, contrast agent peak arrival time, and the like, is logged in a database (142), providing additional diagnostic information or timing information for future reference. In this manner, more accurate images of vessel lumina, as well as blood flow time variant effects, are obtained.

Claims

1. An angiographic imaging method comprising:

generating a plurality of temporally displaced volumetric image representations of a volume of interest, each depicted by a three-dimensional array of voxel values;

temporally collapsing the plurality of three-dimensional arrays of voxel values in accordance with a selected criterion to generate a temporally collapsed three-dimensional array of voxel values; and

projecting in a selected direction the temporally collapsed three-dimensional array of voxel values in accordance with the selected criterion to generate a two-dimensional image representation.

2. The method according to claim 1, wherein the two-dimensional image representation is a maximum intensity projection and wherein the temporally collapsing step includes:

for corresponding voxels of each of the temporally displaced image representations, selecting a one of the voxel values with a maximum intensity.

3. The method according to claim 1, wherein the two-dimensional image representation is a minimum intensity projection and wherein the temporally collapsing step includes:

for corresponding voxels of each of the temporally displaced image representations, selecting a one of the voxel values with a minimum intensity.

4. The method according to claim 1, wherein the step of generating a plurality of temporally displaced volumetric image representations includes:

establishing a polarizing magnetic field in a volume of interest comprising a plurality of voxels;

applying a magnetic resonance scanning pulse sequence to excite resonance of selected dipoles in the volume of interest to generate spatially encoded magnetic resonance signals, said scanning pulse sequence selected from a three-dimensional scanning pulse sequence for generating spatially encoded magnetic resonance signals in the volume of interest and a two-dimensional scanning pulse sequence applied to a plurality of adjacent slices for generating spatially encoded magnetic resonance signals in the volume of interest;

receiving and sampling the magnetic resonance signals to generate k-space data; and

converting the k-space data into a three-dimensional array of voxel intensities.

5. The method according to claim 1, further comprising:

before generating the image representations, administering a contrast agent to the volume of interest, such that at least some of the image representations are generated as the contrast agent is moving through the volume of interest.

6. The method according to claim 1, wherein the volumetric image representations are generated with one of a time-of-flight magnetic resonance angiographic technique and a phase contrast magnetic resonance angiographic technique.

7. The method according to claim 1, further including:

during the generation of the temporally displaced volumetric image representations, controlling acquisition of data from the volume of interest in accordance with a monitored physiological movement.

8. The method according to claim 1, further including:

during the generation of the temporally displaced volumetric image representations, controlling acquisition of data from the volume of interest in accordance with a cardiac cycle.

9. The method according to claim 1, further comprising:

logging time course information for one or more voxel positions of the volume of interest, the time course information including at least one of blood flow rate information, vessel wall dynamics information, contrast agent propagation information , and contrast agent peak arrival time information.

10. The method according to claim 1, wherein the projecting step is performed prior to the temporally collapsing step.

11. A diagnostic imaging method comprising:

generating a plurality of temporally displaced volumetric image representations of a volume of interest, each depicted by a three-dimensional array of voxel values; and

spatially and temporally collapsing the plurality of three-dimensional arrays of voxel values in accordance with a selected criterion to generate a spatially and temporally collapsed two-dimensional image representation.

12. The method of claim 11, wherein the spatially and temporally collapsing step includes:

temporally collapsing the plurality of three-dimensional arrays of voxel values in accordance with a selected criterion to generate a temporally collapsed three-dimensional array of voxel values; and

spatially projecting in a selected direction the temporally collapsed three-dimensional array of voxel values in accordance with the selected criterion to generate the spatially and temporally collapsed two-dimensional image representation.

13. The method according to claim 12, further including:

before the temporally collapsing step, defining a criterion for assigning intensity values for voxels of the temporally collapsed three-dimensional array, the criteria selected from a maximum and minimum value for corresponding voxel positions of the temporally displaced volumetric image representations; and

examining the voxel values and determining a maximum or minimum value for each corresponding voxel position in the plurality of temporally displaced volumetric image representations.

14. The method of claim 11, wherein the spatially and temporally collapsing step includes:

spatially projecting in a selected direction each of said temporally displaced volumetric image representations in accordance with a selected criterion to generate a plurality of temporally displaced two-dimensional image representations; and

temporally collapsing the plurality of two-dimensional image representations in accordance with the selected criterion to generate the spatially and temporally collapsed two-dimensional image representation.

15. The method according to claim 14, further including:

before the spatially projecting step, defining a criterion for spatially projecting each of said temporally displaced volumetric image representations, said criterion selected from a maximum or minimum value voxel value for projection rays in the selected direction; and

examining the voxel values along the projection rays and determining a maximum or minimum value for each ray.

16. An image processing system including:

a reconstruction processor and associated memory for generating and storing a plurality of volume image representations of a volume of interest corresponding to a plurality of offset times;

a time course projection processor and associated memory for temporally collapsing and storing a plurality of temporally offset image representations into a single temporally collapsed image representation;

a spatial projection processor and associated memory for generating two-dimensional spatially projected image representations from volume image representations;

a first of the time course and spatial projection processors being connected with the reconstruction processor and a second of the time course and spatial projection processors being connected with the first for generating a two-dimensional temporally collapsed and spatially projected image representation; and

a display apparatus for converting the two-dimensional temporally collapsed and spatially projected image representation into a human-viewable image.

17. The image processing system according to claim 16, wherein the time course projection processor is connected with the reconstruction processor.

18. The image processing system according to claim 16, wherein the spatial projection processor is connected with the reconstruction processor.

19. The image processing system according to claim 16, wherein the plurality of volume image representations are temporally collapsed by assigning the maximum intensity in time course for corresponding voxel positions, and further wherein the two-dimensional image representation is a maximum intensity projection.

20. The image processing system according to claim 16, wherein the plurality of volume image representations are temporally collapsed by assigning the minimum intensity in time course for corresponding voxel positions, and further wherein the two-dimensional image representation is a minimum intensity projection.

21. The image processing system according to claim 16, further comprising an electrocardiographic sensor.

22. The image processing system according to claim 16, further comprising a database containing time course information for one or more voxel positions of the volume of interest, the time course information including blood flow rate information, vessel wall dynamics information, contrast agent propagation information, or contrast agent peak arrival time information.

23. An angiographic imaging method comprising:

generating multiple volumetric image representations of a given volume of interest, each image representation depicted by a three-dimensional array of voxel values, and each image representation depicting the volume of interest at a different time;

performing one of a maximum and minimum intensity time course projection of the multiple image representations to generate a temporally-collapsed, three-dimensional array of voxel values; and

generating one of a maximum and minimum intensity projection of the temporally collapsed, three-dimensional array of voxel values.

24. An angiographic imaging method comprising:

generating multiple volumetric image representations of a given volume of interest, each image representation depicted by a three-dimensional array of voxel values, and each image representation acquired at a different time with one of a time-of-flight magnetic resonance angiographic technique and a phase contrast magnetic resonance angiographic technique;

performing a time course projection of the plurality of three-dimensional arrays of voxel values to generate a temporally projected three-dimensional array of voxel values; and

projecting in a selected direction the temporally projected three-dimensional array of voxel values to generate a two-dimensional image representation.

25. An angiographic imaging method comprising:

generating multiple volumetric image representations of a given volume of interest, each image representation depicted by a three-dimensional array of voxel values, the image representations being displaced in time;

logging time course information for one or more voxel positions of the volume of interest in accordance with cardiac phase;

performing a time course projection of subsets of plurality of three-dimensional arrays of voxel values with corresponding cardiac phase to generate cardiac phase corresponding three-dimensional array of voxel values; and

spatially projecting each cardiac phase corresponding three-dimensional array of voxel values to generate corresponding two-dimensional image representations.

26. A diagnostic imaging method comprising:

generating multiple volumetric image representations of a given volume of interest, each image representation depicted by a three-dimensional array of voxel values, and each image representation depicting the volume of interest at a different time;

spatially projecting, in a selected direction, each of said temporally displaced volumetric image representations to generate a plurality of temporally displaced two-dimensional image representations; and

temporally projecting the plurality of two-dimensional image representations to generate a single two-dimensional image representation.

27. An angiographic imaging method comprising:

generating a plurality of temporally displaced volumetric image representations of a subvolume of interest, each depicted by a three-dimensional array of voxel values, said subvolume of interest being contained within a larger volume of interest;

temporally collapsing the plurality of three-dimensional arrays of voxel values in accordance with a selected criterion to generate a temporally collapsed three-dimensional array of voxel values; and

projecting in a selected direction the temporally collapsed three-dimensional array of voxel values in accordance with the selected criterion to generate a two-dimensional image representation of the subvolume of interest.

28. The method of claim 27, further comprising:

generating a two-dimensional image representation of the volume of interest comprising;

said two-dimensional image representation of the subvolume of interest; and

non-time resolved voxel intensity values representing areas within the volume of interest which are outside the subvolume of interest.