System and method for X-ray imaging

Patent metadata

Field	Value
Publication number	US-11724128-B2
Application number	US-202117156655-A
Country	US
Kind code	B2
Filing date	Jan 25, 2021
Priority date	Nov 26, 2015
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

The present disclosure provides a system and method for X-ray imaging. The method of calculating scatter in an X-ray image may include forming a modulated X-ray image. The method of forming the modulated X-ray image may include acquiring X-rays through a collimator module and an imaged object in sequence to generate an X-ray image group; the acquisition may be performed during a movement of the collimator module in a first direction and the X-ray image group may include a plurality of X-ray images acquired at different times during the movement of the collimator; extracting sub-zones from the plurality of X-ray images in the X-ray image group; combining the sub-zones in the first direction to form the modulated X-ray image. In the present disclosure, an intensity distribution of the X-rays may be adjusted flexibly using a collimator without adding any extra hardware. In addition, scatter components in the X-ray images may be calculated to eliminate the scatter in the X-ray images finally.

First claim

What is claimed is:

1. A method for using in an X-ray image device, comprising:
forming a modulated X-ray image, comprising:
acquiring X-rays through a collimator module and an imaged object in sequence to generate an X-ray image group including a plurality of X-ray images;
wherein the collimator module includes one or more pairs of collimators each of which includes collimators arranged within a distance in a first direction and the acquisition is performed during a movement of the collimator module in the first direction; and

determining the modulated X-ray image based on the plurality of X-ray images, the modulated X-ray image including dark stripes and bright stripes.

2. The method of claim 1 , wherein an acquisition frequency for obtaining the X-ray image group is proportional to a speed of the movement of the collimator module.

3. The method of claim 1 , wherein each pair of the one or more pairs of collimators is a multi-leaf collimator comprising a group of leaves, and wherein the group of leaves are equal in length and move together in the first direction.

4. The method of claim 1 , wherein during the movement of the collimator module, at least one pair of the one or more pairs of collimators keep the distance and move at a periodic speed.

5. The method of claim 4 , wherein the periodic speed is at least one of a periodically increasing speed or a periodically decreasing speed.

6. The method of claim 1 , wherein during the movement of the collimator module, a first collimator of each pair of the one or more pairs of collimators is fixed, and a second collimator of each pair of the one or more pairs of collimators moves.

7. The method of claim 1 , the determining the modulated X-ray image based on the plurality of X-ray images includes:
extracting a sub-zone from each of the plurality of X-ray images, the sub-zone including a bright stripe and a dark stripe; and
combining the sub-zones in the first direction to form the modulated X-ray image.

8. The method of claim 7 , wherein the bright stripe of the sub-zone in each of the plurality of X-ray images is at a region corresponding to an edge of a moving collimator of each pair of the one or more pairs of collimators.

9. The method of claim 1 , further comprising:
low-pass filtering the modulated X-ray image to obtain a combination of a low-frequency portion of the modulated X-ray image and scatter components of the modulated X-ray image;
high-pass filtering the modulated X-ray image to obtain a high-frequency portion of the modulated X-ray image;
calculating an estimate of the low-frequency portion of the modulated X-ray image based on the high-frequency portion of the modulated X-ray image; and
calculating the scatter components based on the estimate of the low-frequency portion of the modulated X-ray image and the combination of the low-frequency portion of the modulated X-ray image and the scatter components of the modulated X-ray image.

10. A method of X-ray image reconstruction, comprising:
acquiring X-ray projection images of an imaged object, wherein the acquisition is performed during a movement of a collimator module in a first direction;
determining a modulated X-ray image based on the X-ray projection images, the modulated X-ray image representing bright stripes and dark stripes;
determining scatter components of the modulated X-ray image;
determining scatter components of the X-ray projection images based on the scatter components of the modulated X-ray image; and
obtaining at least one reconstructed image based on the X-ray projection images and the scatter components of the X-ray projection images.

11. The method of claim 10 , wherein an acquisition frequency for obtaining the X-ray projection images is proportional to a speed of movement of the collimator module.

12. The method of claim 10 , wherein each pair of the one or more pairs of collimators is a multi-leaf collimator comprising a group of leaves, and wherein the group of leaves are equal in length and move together in the first direction.

13. The method of claim 10 , wherein during the movement of the collimator module, the one or more pairs of collimators move at a periodic speed.

14. The method of claim 13 , wherein the periodic speed is at least one of a periodically increasing speed or a periodically decreasing speed.

15. The method of claim 10 , wherein during the movement of the collimator module, one of each of the one or more pairs of collimators is fixed, and another one of the one or more pairs of collimators moves.

16. The method of claim 10 , wherein the determining a modulated X-ray image based on the X-ray projection images includes:
extracting a sub-zone from each of the X-ray projection images, the sub-zone including a bright stripe and dark stripe; and
combining the sub-zones in the first direction to form the modulated X-ray image.

17. The method of claim 10 , wherein before determining scatter components of the modulated X-ray image, the method further includes:
processing the modulated X-ray image by downsampling at a center line of every bright and dark stripe.

18. The method of claim 10 , wherein the determining scatter components of the modulated X-ray image includes:
low-pass filtering the modulated X-ray image to obtain a combination of a low-frequency portion of the modulated X-ray image and scatter components of the modulated X-ray image;
high-pass filtering the modulated X-ray image to obtain a high-frequency portion of the modulated X-ray image;
calculating an estimate of the low-frequency portion of the modulated X-ray image after the high-frequency portion is demodulated and weighted; and
calculating the scatter components by subtracting the estimate of the low-frequency portion of the modulated X-ray image from the combination of low-frequency portion and the scatter components of the low-pass filtered modulated X-ray image.

19. The method of claim 10 , the determining scatter components of the X-ray projection images based on the scatter components of the modulated X-ray image includes:
designating the scatter components of the modulated X-ray image as the scatter components of the X-ray projection images.

Assignees

• Shanghai United Imaging Healthcare Co Ltd

Inventors

• Li Gui
• Xu Lu
• Yang Hongcheng

Classifications

• G06T2207/20224

  Image subtraction · CPC title

• G06T5/73

  Deblurring; Sharpening · CPC title

• G06T5/70

  Denoising; Smoothing · CPC title

• A61N5/1049 Primary

  for verifying the position of the patient with respect to the radiation beam · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title