Generating a 2D projection image of a vascular system

1. A method for generating at least one two-dimensional (2D) projection image of a vascular system of a body region of interest, the method comprising:

acquiring a three-dimensional (3D) angiographic image of the body region of interest including a plurality of vessels;

acquiring at least one 2D projection image of the body region of interest including a plurality of vessel projections, wherein the at least one 2D projection image is generated by digital subtraction angiography (DSA);

generating a modified 3D angiographic image by eliminating vessels within the plurality of vessels individually having a vessel size that exceeds a first predetermined limit value;

normalizing the 2D projection image using projection data obtained from the modified 3D angiographic image;

eliminating vessel projections within the plurality of vessel projections in the normalized 2D projection image individually having a vessel projection size that exceeds a second predetermined limit value;

interpolating areas of the normalized 2D projection image in which the vessel projections have been eliminated, wherein the eliminated vessel projections and a corresponding area containing the eliminated vessel projections are filled with artifical data;

denormalizing the normalized and interpolated 2D projection image using projection data of the modified 3D angiographic image such that parenchymal vessels included within the corresponding area of the eliminated vessel projections are reintroduced; and

displaying, by a display apparatus, the denormalized 2D projection image.

2. The method as claimed in claim 1 , wherein the vessels within the plurality of vessels of the 3D angiographic image whose size exceeds the first predetermined limit value are projected into the 2D projection image, and

wherein the elimination of the vessel projections within the plurality of vessel projections in the normalized 2D projection image whose size exceeds the second predetermined limit value is carried out based on the plurality of vessels of the 3D angiographic image.

3. The method as claimed in claim 2 , wherein the 3D angiographic image is generated by computed tomography (CT), magnetic resonance tomography (MRT), or C-arm-based imaging.

4. The method as claimed in claim 1 , wherein the acquiring of the 3D angiographic image is performed based on a subtraction.

5. The method as claimed in claim 4 , further comprising:

performing a segmentation of at least the plurality of vessels in the 3D angiographic image following the acquisition of the 3D angiographic image.

6. The method as claimed in claim 1 , wherein the 3D angiographic image is generated by computed tomography (CT), magnetic resonance tomography (MRT), or C-arm-based imaging.

7. The method as claimed in claim 1 , wherein the at least one 2D projection image comprises a time series of 2D projection images.

8. The method as claimed in claim 7 , further comprising:

generating a final 2D projection image from the time series of 2D projection images, the final 2D projection image comprising time information about an inflow of contrast agent into the vascular system.

9. The method as claimed in claim 8 , wherein an associated modified 3D angiographic image is generated for each image of the time series of projection images, wherein regions of the vascular system that are not filled with the inflow of contrast agent in the respective 2D projection image are eliminated in the 3D angiographic image, and

wherein the normalizing, the denormalizing, or both the normalizing and the denormalizing are/is performed for each image of the time series of projection images based on the associated modified 3D angiographic image in each case.

10. The method as claimed in claim 7 , wherein an associated modified 3D angiographic image is generated for each image of the time series of projection images, wherein regions of the vascular system that are not filled in the respective 2D projection image are eliminated in the 3D angiographic image, and

wherein the normalizing, the denormalizing, or both the normalizing and the denormalizing are/is performed for each image of the time series of projection images based on the associated modified 3D angiographic image in each case.

11. The method as claimed in claim 1 , further comprising:

performing a segmentation of at least the pluralty of vessels in the 3D angiographic image following the acquisition of the 3D angiographic image.

12. The method as claimed in claim 1 , wherein the normalizing is performed pixel by pixel, the denormalizing is performed pixel by pixel, or both the normalizing and the denormalizing are performed pixel by pixel.

13. The method as claimed in claim 1 , further comprising:

displaying, by the display apparatus, the modified 3D angiographic image.

14. The method as claimed in claim 1 , wherein the generating of the modified 3D angiographic image comprises eliminating afferent vessels and efferent vessels.

15. A computing device comprising:

at least one processor; and

at least one non-transitory computer readable medium including computer program code for one or more programs; the at least one non-transitory computer readable medium and the computer program code configured to, with the at least one processor, cause the computing device to at least perform:

acquire a three-dimensional (3D) angiographic image of the body region of interest including a plurality of vessels;

acquire at least one 2D projection image of the body region of interest including a plurality of vessel projections, wherein the at least one 2D projection image is generated by digital subtraction angiography (DSA);

generate a modified 3D angiographic image by eliminating vessels within the plurality of vessels individually having a vessel size that exceeds a first predetermined limit value;

normalize the 2D projection image using projection data obtained from the modified 3D angiographic image;

eliminate vessel projections within the plurality of vessel projections in the normalized 2D projection image individually having a vessel projection size that exceeds a second predetermined limit value;

interpolate areas of the normalized 2D projection image in which the vessel projections have been eliminated, wherein the eliminated vessel projections and a corresponding area containing the eliminated vessel projections are filled with artifical data;

denormalize the normalized and interpolated 2D projection image using projection data of the modified 3D angiographic image such that parenchymal vessels included within the corresponding area of the eliminated vessel projections are reintroduced; and

display the denormalized 2D projection image.

16. A device for generating at least one 2D projection image of a vascular system of a body region of interest, the device comprising:

a first acquisition apparatus for acquiring a 3D angiographic image of the body region of interest;

a second acquisition apparatus for acquiring at least one 2D projection image of the body region of interest, wherein the at least one 2D projection image is generated by digital subtraction angiography (DSA); and

a computing device having at least one processor, the computing device configured to:

acquire the three-dimensional (3D) angiographic image of the body region of interest including a plurality of vessels;

acquire the at least one 2D projection image of the body region of interest including a plurality of vessel projections;

generate a modified 3D angiographic image by eliminating vessels within the plurality of vessels individually having a vessel size that exceeds a first predetermined limit value;

normalize the 2D projection image using projection data obtained from the modified 3D angiographic image;

eliminate vessel projections within the plurality of vessel projections in the normalized 2D projection image individually having a vessel projection size that exceeds a second predetermined limit value;

interpolate areas of the normalized 2D projection image in which the vessel projections have been eliminated, wherein the eliminated vessel projections and a corresponding area containing the eliminated vessel projections are filled with artifical data;

denormalize the normalized and interpolated 2D projection image using projection data of the modified 3D angiographic image such that parenchymal vessels included within the corresponding area of the eliminated vessel projections are reintroduced; and

display the denormalized 2D projection image.