System and method for couch sag compensation in image guided radio therapy

Patent metadata

Field	Value
Publication number	US-10166407-B2
Application number	US-201715661023-A
Country	US
Kind code	B2
Filing date	Jul 27, 2017
Priority date	May 27, 2017
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

A method and system for using in a two-modality apparatus. The two-modality apparatus comprises a couch with a table top, a first modality unit and a second modality unit. A second image of a target portion of an object when the table top is at a second working position of the second modality unit may be acquired. A second sag of the table top at a second measurement point of the table top according to the second image may be determined based on the image. A difference between a first sag of the table top at a first measurement point of the table top and the second sag may be estimated based on the second sag and standard data. The standard data provides a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit.

First claim

We claim:

1. A method for using in a two-modality apparatus, wherein the two-modality apparatus comprises a couch with a table top, a first modality unit having a first isocenter, a second modality unit having a second isocenter, the method comprising:
acquiring an image of a target portion of the object when the table top is at a second working position of the second modality unit;
determining a second sag of the table top at a second measurement point of the table top according to the image, the second measurement point of the table top relating to the second isocenter of the second modality unit;
retrieving standard data that provide a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit; and
estimating, based on the second sag and the standard data, a first sag of the table top at a first measurement point of the table top when the table top carrying an object is at a first working position of the first modality unit, the first measurement point of the table top relating to the first isocenter of the first modality unit.

2. The method of claim 1 , further comprising:
adjusting, based on the first sag, the position of the table top in a vicinity of the first working position of the first modality unit.

3. The method of claim 2 , the adjusting the position of the table top in the vicinity of the first working position of the first modality unit comprising:
causing the two-modality apparatus to move the table top to a vicinity of the first working position of the first modality unit based on the first sag.

4. The method of claim 1 , wherein the standard data comprise a plurality of standard data sets, and at least one of the plurality of standard data sets comprises a first standard parameter and a second standard parameter, and wherein:
the first standard parameter includes a relationship between a couch sag of the table top and an amount of extension of the table top when the table top is at a working position of the first modality unit, and
the second standard parameter includes a relationship between a couch sag of the table top and an amount of extension of the table top when the table top is at a working position of the second modality unit.

5. The method of claim 4 , wherein the second standard parameter is determined based on at least one image, wherein the at least one image is acquired at the working position of the first modality unit and with the weight of the object carried on the table top.

6. The method of claim 4 , wherein the second standard parameter is determined based on data collected by one or more sensors.

7. The method of claim 1 , the estimating the first sag comprising:
determining a difference between the first sag and the second sag.

8. The method of claim 7 , the estimating the first sag comprising:
obtaining a weight of the object, and
determining the first sag of the table top based on the obtained weight of the object, a first amount of extension of the table top at a working position of the first modality unit, and the first standard parameter.

9. The method of claim 8 , the obtaining the weight of the object comprising:
estimating the weight of the object based on the second sag, a second amount of extension of the table top at the working position of the second modality unit, and the second standard parameter.

10. The method of claim 1 , the acquiring the image of the target portion of the object when the table top is at the second working position of the second modality unit comprising:
moving the table top to the second working position of the second modality unit.

11. The method of claim 1 , wherein the first modality unit is a Linear Accelerator (LINAC) device.

12. The method of claim 11 , wherein the second modality unit is a computed tomography (CT) device.

13. A system comprising:
a two-modality apparatus, wherein the two-modality apparatus comprises a couch with a table top, a first modality unit having a first isocenter, and a second modality unit having a second isocenter;
at least one processor, and
a set of instructions stored in a storage device that, when executed by the at least one processor, cause the system to effectuate a method comprising:
acquiring an image of a target portion of the object when the table top is at a second working position of the second modality unit;
determining a second sag of the table top at a second measurement point of the table top according to the image, the second measurement point of the table top relating to the second isocenter of the second modality unit;
retrieving standard data that provide a relationship relating to a sag of the table top positioned between the first modality unit and second modality unit; and
estimating, based on the second sag and the standard data, a first sag of the table top at a first measurement point of the table top when the table top carrying an object is at a first working position of the first modality unit, the first measurement point of the table top relating to the first isocenter of the first modality unit.

14. The system of claim 13 , wherein the set of instructions, when executed by the at least one processor, further cause the system to:
adjust, based on the first sag, the position of the table top in a vicinity of the first working position of the first modality unit.

15. The system of claim 14 , the adjusting the position of the table top in the vicinity of the first working position of the first modality unit comprising:
causing the two-modality apparatus to move the table top to a vicinity of the first working position of the first modality unit based on the first sag.

16. The system of claim 13 , wherein the standard data comprise a plurality of standard data sets, and at least one of the plurality of standard data sets comprises a first standard parameter and a second standard parameter, and wherein:
the first standard parameter includes a relationship between a couch sag of the table top and an amount of extension of the table top when the table top is at a working position of the first modality unit, and
the second standard parameter includes a relationship between a couch sag of the table top and an amount of extension of the table top when the table top is at a working position of the second modality unit.

17. The system of claim 13 , wherein the first standard parameter or the second standard parameter is in the form of a table.

18. The system of claim 13 , the estimating the first sag comprising:
determining a difference between the first sag and the second sag.

19. The system of claim 18 , the estimating the first sag comprising:
obtaining a weight of the object, and
determining the first sag of the table top based on the obtained weight of the object, a first amount of extension of the table top at a working position of the first modality unit, and the first standard parameter.

20. A non-transitory computer readable medium comprising executable instructions that, when executed by at least one processor, cause the at least one processor to effectuate a method for using in a two-modality apparatus, wherein the two-modality apparatus comprises a couch with a table top, a first modality unit having a first isocenter, and a second modality unit having a second isocenter, the method comprising:
acquiring an image of a target portion of the object when the table top is at a second working position of the second modality unit;
determining a second sag of the table top at a second me

Assignees

• Shanghai United Imaging Healthcare Co Ltd

Inventors

• Stahl Johannes
• Bose Supratik
• Maltz Jonathan
• Xu Lu
• Chen Hao

Classifications

• G06T7/73

  using feature-based methods · CPC title

• G06T7/33 Primary

  using feature-based methods · CPC title

• A61B6/563

  involving image data transmission via a network · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title

• A61N2005/1074

  Details of the control system, e.g. user interfaces · CPC title