X-ray position tracking

Patent metadata

Field	Value
Publication number	US-12226245-B2
Application number	US-202118017143-A
Country	US
Kind code	B2
Filing date	Jul 16, 2021
Priority date	Jul 30, 2020
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

A spectral X-ray imaging system ( 100 ) includes an X-ray source ( 110 ) and an X-ray detector ( 120 ) that are mounted to a support structure ( 150 ). The support structure ( 150 ) is configured to rotate the X-ray source ( 110 ) and the X-ray detector ( 120 ) around two or more orthogonal axes (A-A′, B-B′). One or more processors ( 130 ) are configured to cause the system ( 100 ) to perform operations that include: generating a spectral image based on the spectral image data; and identifying, in the spectral image, a position of a first fiducial marker ( 180 i ) comprising a first material, based on a first X-ray absorption k-edge energy value ( 190 i ) of the first material.

First claim

The invention claimed is:

1. A spectral X-ray imaging system comprising:
an X-ray source and an X-ray detector configured to generate spectral image data representing attenuation of X-rays traversing an imaging region between the X-ray source and the X-ray detector, for each of three or more energy intervals of the X-rays;
a support structure is configured to rotate the X-ray source and the X-ray detector around two or more orthogonal axes; and
one or more processors configured to:
generate a spectral image based on the spectral image data,
identify, in the spectral image, a position of a first fiducial marker comprising a first material, based on a first X-ray absorption k-edge energy value of the first material, and
identify, in the spectral image, a position of a second fiducial marker comprising a second material, based on a second X-ray absorption k-edge energy value of the second material, the second X-ray absorption k-edge energy value being different to the first X-ray absorption k-edge energy value.

2. The spectral X-ray imaging system according to claim 1 , wherein the spectral image discriminates between the first and second materials and at least a further material, and wherein the further material comprises: tissue, bone, water, air, contrast agent, or metal.

3. The spectral X-ray imaging system according to claim 1 , wherein, to generate the spectral image, the one or more processors are further configured to:
apply, in a projection domain, a material decomposition algorithm to the spectral image data to provide a first projection image representing the first material, and a second projection image representing a second material; and
fuse the first projection image and the second projection image to provide the spectral image.

4. The spectral X-ray imaging system according to claim 1 , wherein, to generate the spectral image, the one or more processors are further configured to:
reconstruct a first volumetric image representing the first material;
reconstruct a second volumetric image representing the second material; and
fuse the first volumetric image and the second volumetric image to provide the spectral image.

5. The spectral X-ray imaging system according to claim 4 , wherein the fusing comprises forward projecting the first volumetric image and the second volumetric image to provide the spectral image as a projection image.

6. The spectral X-ray imaging system according to claim 4 , wherein to generate the spectral image, the one or more processors are further configured to:
apply, in a projection domain, a material decomposition algorithm to the spectral image data to provide first sinogram data representing the first material, and second sinogram data representing the second material;
reconstruct the first volumetric image from the first sinogram data; and
reconstruct the second volumetric image from the second sinogram data;
and wherein reconstructing the first volumetric image and reconstructing the second volumetric image comprises applying a filtered back-projection algorithm to the first sinogram data and to the second sinogram data respectively.

7. The spectral X-ray imaging system according to claim 4 , wherein to generate the spectral image, the one or more processors are further configured to:
reconstruct an energy channel image for each of the three or more energy intervals; and
generate the first volumetric image and the second volumetric image from the reconstructed energy channel image for each of the three or more energy intervals using a material decomposition algorithm;
and wherein generating the first volumetric image and the second volumetric image is based on first calibration data representing attenuation of the X-rays by a first object comprising the first material, and second calibration data representing attenuation of the X-rays by a second object comprising the second material, and wherein the first object and the second object are disposed in known positions in the imaging region.

8. The spectral X-ray imaging system according to claim 4 , wherein the spectral image is generated using an iterative one-step inversion algorithm to simultaneously reconstruct the first volumetric image and the second volumetric image.

9. The spectral X-ray imaging system according to claim 1 , wherein the spectral image is generated by generating first image data representing the first material, and generating second image data representing the second material; and
wherein the identifying, in the spectral image, the position of the first fiducial marker and the position of the second fiducial marker comprises applying a feature detection algorithm to the first image data and the second image data, respectively.

10. The spectral X-ray imaging system according to claim 9 , wherein to apply the feature detection algorithm to the first image data and the second image data, the one or more processors is further configured to at least one of:
analyze at least one of the first image data or the second image data, to determine a position in the spectral image corresponding to a maximum image intensity in at least one of the first image data or the second image data, respectively; and
analyze at least one of the first image data or the second image data, to determine a position in the spectral image corresponding to a predetermined image intensity pattern in at least one of the first image data or the second image data, respectively.

11. The spectral X-ray imaging system according to claim 9 , wherein to apply the feature detection algorithm to the first image data and the second image data, the one or more processors are further configured to:
analyze the first image data and the second image data; to determine a position and/or orientation in the spectral image of an interventional instrument or an implantable device comprising the first fiducial marker and the second fiducial marker respectively, based on a model representing X-ray attenuation of the interventional instrument or the implantable device.

12. The spectral X-ray imaging system according to claim 1 , wherein the one or more processors are further configured to track a position of the first and second fiducial markers in an interventional imaging procedure.

13. An interventional instrument for use with the system according to claim 1 , the interventional instrument comprising at least two fiducial markers comprising the first fiducial marker comprising the first material having the first X-ray absorption k-edge energy value and the second fiducial marker comprising the second material having the second X-ray absorption k-edge energy value, the second X-ray absorption k-edge energy value being different to the first X-ray absorption k-edge energy value.

14. A kit comprising a first interventional instrument and a second interventional instrument for use with the system according to claim 1 ;
wherein the first interventional instrument comprises the first fiducial marker comprising the first material having the first X-ray absorption k-edge energy value; and
wherein the second interventional instrument comprises the second fiducial marker comprising the second material having the second X-ray absorption k-edge energy value, the second X-ray absorption k-edge energy value being different to the first X-ray absorption k-edge energy value.

15. A computer-implemented method of processing spectral image data representing attenuation of X-rays traversing an imaging region between an X-ray source and an X-ray detector, the method comprising:
generating a spectral image based on the spectral image data;
identifying,

Assignees

• Koninklijke Philips Nv

Inventors

• Erhard Klaus Alfred
• Daerr Heiner
• Sossin Artur
• Thran Axel
• Brendel Bernhard Johannes
• Haase Christian
• Bontus Claas

Classifications

• A61B6/52

  Devices using data or image processing specially adapted for radiation diagnosis · CPC title

• A61B6/4441

  the rigid structure being a C-arm or U-arm · CPC title

• A61F2/852

  Two or more distinct overlapping stents · CPC title

• A61B2090/3966

  Radiopaque markers visible in an X-ray image · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title