System and method for x-ray imaging

Patent metadata

Field	Value
Publication number	US-10898154-B2
Application number	US-201615361036-A
Country	US
Kind code	B2
Filing date	Nov 24, 2016
Priority date	Nov 26, 2015
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

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 a pair of collimators arranged within a distance in a first direction, the acquisition is performed during a movement of the collimator module in the first direction, and the pair of collimators, during the movement of the collimator module, keep the distance and move at a periodic speed—
extracting sub-zones from the plurality of X-ray images in the X-ray image group; and
combining the sub-zones in the first direction to form the modulated X-ray image.

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

3. The method of claim 1 , wherein the collimator module 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. 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 of a plurality of X-ray images;
wherein the acquisition is performed during a movement of the collimator module in a first direction;
wherein the collimator module comprises a pair of collimators arranged within a distance in the first direction; and
wherein during the movement of the collimator module, the pair 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 , 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 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.

7. A method of X-ray image reconstruction, comprising;
acquiring X-ray projection images of an imaged object from different projection angles; wherein the acquisition is performed during a movement of a collimator module in a first direction, and wherein the X-ray projection images are acquired at different times during the movement of the collimator module;
calculating scatter components of the projection images, comprising:
low-pass filtering a 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;
calculating the scatter components by subtracting the estimate of the low-frequency portion of the modulated X-ray image from the combination of the low-frequency portion and the scatter components of the low-pass filtered modulated X-ray image; and
obtaining at least one reconstructed image by reconstructing the projection images from which the scatter components are subtracted.

8. An apparatus, comprising:
a first acquisition unit configured to acquire 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 a pair of collimators arranged within a distance in a first direction; and
wherein the acquisition is performed during a movement of the collimator module in the first direction, and the pair of collimators, during the movement of the collimator module, keep the distance and move at a periodic speed;
an extraction unit configured to extract sub-zones from the X-ray images in the X-ray image group; and
a combination unit configured to combine the sub-zones in the first direction to form the modulated X-ray image.

9. The apparatus of claim 8 , further comprising an X-ray image scatter calculation device comprising;
a low-pass filter unit configured to low-pass filter the modulated X-ray image to obtain a combination of a low-frequency portion and scatter components of the modulated X-ray image;
a high-pass filter unit configured to high-pass filter the modulated X-ray image to obtain a high-frequency portion of the modulated X-ray image;
a low-frequency estimate unit configured to demodulate the high-frequency portion of the modulated X-ray image and weight the high-frequency portion to obtain an estimate of the low-frequency portion of the modulated X-ray image; and
a scatter calculation unit configured to obtain at least one scatter component by subtracting the estimate of low-frequency portion of the modulated X-ray image from the combination of the low-frequency portion and scatter components of the modulated X-ray image.

10. The apparatus of claim 8 , further comprising an X-ray image reconstruction apparatus comprising:
a second acquisition unit configured to acquire X-ray projection images of an imaged object from different projection angles:
a reconstruction unit configured to reconstruct at least one image based on the X-ray projection images from which scatter components are subtracted; and
an X-ray image scatter component calculation device configured to calculate scatter components of the X-ray projection images.

11. The method of claim 4 , 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 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.

12. The method of claim 1 , wherein the periodic speed is at least one of a periodically increasing speed or a periodically decreasing speed.

13. The method of claim 4 , wherein an acquisition frequency for obtaining the X-ray image group is proportional to a speed of movement of the collimator module.

14. The apparatus of claim 8 , wherein the periodic speed is at least one of a periodically increasing speed or a periodically decreasing speed.

15. The apparatus of claim 8 , wherein an acquisition frequency for obtaining the X-ray image group is proportional to a speed of movement of the collimator module.

16. The apparatus of claim 8 , wherein the collimator module 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

Assignees

• Shanghai United Imaging Healthcare Co Ltd

Inventors

• Li Gui
• Xu Lu
• Yang Hongcheng

Classifications

• A61B6/06

  Diaphragms · CPC title

• A61B6/5217

  extracting a diagnostic or physiological parameter from medical diagnostic data · CPC title

• A61B6/5282 Primary

  due to scatter · 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