Particle therapy system

• US 6,774,383 B2
• Filed: 03/25/2003
• Issued: 08/10/2004
• Est. Priority Date: 03/26/2002
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hiramoto, Kazuo, Umezawa, Masumi, Norimine, Tetsuro
• Primary Examiner(s): Wells, Nikita
• Application Number:
  US10/395,144
• Publication Number:
  US 20030183779A1
• Time in Patent Office: 504 Days
• Field of Search: 250/505.1, 250/492.3, 315/503, 315/507, 378/65
• US Class Current: 250/505.1
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1048 Monitoring, verifying, controlling systems and methods
• CPC Class Codes: A61N 5/1065 Beam adjustment
• CPC Class Codes: G21K 1/093 by magnetic means
• CPC Class Codes: G21K 5/04 with beam-forming means
• CPC Class Codes: H05H 7/04 Magnet systems , e.g. undulators, wigglers free-electron laser H01S3/0903; Energisation thereof

Abstract

A particle therapy system is provided which can simply and quickly correct a beam orbit. In a particle therapy system provided with an irradiation facility comprising a first beam transport system for receiving a beam and transporting the beam to the patient side, and an irradiation nozzle for forming an irradiation field of the beam, the particle therapy system comprises first beam position monitors for detecting a position upstream of the irradiation nozzle at which the beam passes, second beam position monitors for detecting a position downstream of the irradiation nozzle at which the charged-particle beam passes, and first and second steering magnets. Correction bending amounts for causing the beam to be coincident with a predetermined orbit after the correction are determined in accordance with detected results from the first and second beam position monitors, and first and second steering magnets are excited under control so that the determined correction bending amounts are obtained.

Claims

1. A particle therapy system comprising an accelerator for accelerating a charged-particle beam to a set level of energy, and a rotating irradiation facility for irradiating the charged-particle beam extracted from said accelerator, said irradiation facility comprising first beam transport appratus for transporting the charged-particle beam extracted from said accelerator, and irradiation field forming appratus for forming an irradiation field of the charged-particle beam transported by said first beam transport appratus, wherein said particle therapy system further comprises:

first beam position detecting appratus arranged along an orbit of the charged-particle beam downstream of a most downstream one of magnets provided in said first beam transport appratus, and detecting a position at which the charged-particle beam passes;

second beam position detecting appratus arranged along the orbit of the charged-particle beam downstream of said first beam position detecting appratus, and detecting a position at which the charged-particle beam passes;

a first steering magnet and a second steering magnet both provided in said first beam transport appratus upstream of said first beam position detecting appratus;

first displacement amount computing appratus for determining respective first displacement amounts, by which the position of the charged-particle beam is to be displaced by said first and second steering magnets, in accordance with detected signals outputted from said first and second beam position detecting appratus; and

first cotrol system for controlling respective excitation currents of said first and second steering magnets in accordance with the respective first displacement amounts.

2. A particle therapy system according to claim 1, wherein said irradiation field forming appratus includes a first scatterer and a second scatterer arranged downstream of said first scatterer, and said first beam position detecting appratus is arranged upstream of said second scatterer.

3. A particle therapy system according to claim 2, wherein said first displacement amount computing appratus determines the first displacement amounts in accordance with the detected signals outputted from said first and second beam position detecting appratus so that the position of the charged-particle beam comes within a set orbit in said irradiation field forming appratus.

4. A particle therapy system according to claim 1, wherein said irradiation field forming appratus includes beam scanning appratus for scanning the charged-particle beam, and said first beam position detecting appratus is arranged upstream of said beam scanning appratus.

5. A particle therapy system according to claim 4, wherein said first displacement amount computing appratus determines the first displacement amounts in accordance with the detected signals outputted from said first and second beam position detecting appratus so that the position of the charged-particle beam comes within a set orbit in said irradiation field forming appratus.

6. A particle therapy system according to claim 5, wherein said first displacement amount computing apparatus determines the first displacement amounts on the basis of approximation models using a plurality of transfer matrices representing respective transport characteristics of various transport elements of said first beam transport apparatus, which include at least said first and second steering magnets.

7. A particle therapy system according to claim 1, wherein said first displacement amount computing appratus determines the first displacement amounts in accordance with the detected signals outputted from said first and second beam position detecting appratus so that the position of the charged-particle beam comes within a set orbit in said irradiation field forming appratus.

8. A particle therapy system according to claim 7, wherein at least one of said first and second steering magnets displace the charged-particle beam in one direction and displace the charged-particle beam in an other direction perpendicular to the one direction.

9. A particle therapy system according to claim 1, wherein said first displacement amount computing apparatus determines the first displacement amounts on the basis of approximation models using a plurality of transfer matrices representing respective transport characteristics of various transport elements of said first beam transport apparatus, which include at least said first and second steering magnets.

10. A particle therapy system according to claim 1, wherein at least one of said first and second steering magnets displace the charged-particle beam in one direction and displace the charged-particle beam in an other direction perpendicular to the one direction.

11. A particle therapy system according to claim 10, wherein said second displacement amount computing apparatus determines the second displacement amounts on the basis of approximation models using a plurality of transfer matrices representing respective transport characteristics of various transport elements of said second beam transport apparatus, which include at least said third and fourth steering magnets.

12. A particle therapy system comprising an accelerator for accelerating a charged-particle beam to a set level of energy, a rotating irradiation facility for irradiating the charged-particle beam extracted from said accelerator, and second beam transport apparatus for transporting the charged-particle beam extracted from said accelerator to said irradiation facility, wherein said particle therapy system further comprises:

third beam position detecting apparatus for detecting a position in said second beam transport beam transport apparatus at which the charged-particle beam passes;

fourth beam position detecting apparatus for detecting, downstream of said third beam position detecting apparatus, a position in said second beam transport apparatus at which the charged-particle beam passes;

a third steering magnet and a fourth steering magnet both provided in said second beam transport apparatus upstream of said third beam position detecting apparatus;

second displacement amount computing apparatus for determining second displacement amounts, by which the position of the charged-particle beam is to be displaced by said third and fourth steering magnets, in accordance with detected signals outputted from said third and fourth beam position detecting apparatus; and

second control system for controlling respective excitation currents of said third and fourth steering magnets in accordance with the respective second displacement amounts.

13. A particle therapy system according to claim 12, wherein said second displacement amount computing apparatus determines the second displacement amounts in accordance with the detected signals outputted from said third and fourth beam position detecting apparatus so that the position of the charged-particle beam comes within a set orbit in said irradiation field forming apparatus.

14. A particle therapy system according to claim 13, wherein said second displacement amount computing apparatus determines the second displacement amounts on the basis of approximation models using a plurality of transfer matrices representing respective transport characteristics of various transport elements of said second beam transport apparatus, which include at least said third and fourth steering magnets.

15. A particle therapy system according to any one of claim 12, wherein at least one of said third and fourth steering magnets displace the charged-particle beam in one direction and displace the charged-particle beam in an other direction perpendicular to the one direction.

16. A particle therapy system according to any one of claim 13, wherein at least one of said third and fourth steering magnets displace the charged-particle beam in one direction and displace the charged-particle beam in an other direction perpendicular to the one direction.

17. A particle therapy system comprising an accelerator for accelerating a charged-particle beam to a set level of energy, a stationary irradiation facility for irradiating the charged-particle beam, and beam transport apparatus for transporting the charged-particle beam extracted from said accelerator to said irradiation facility, wherein said particle therapy system further comprises:

first beam position detecting apparatus arranged along an orbit of the charged-particle beam downstream of a most downstream one of magnets provided in said beam transport apparatus, and detecting a position at which the charged-particle beam passes;

second beam position detecting apparatus arranged along the orbit of the charged-particle beam downstream of said first beam position detecting apparatus, and detecting a position at which the charged-particle beam passes;

a first steering magnet and a second steering magnet both provided in said beam transport apparatus upstream of said first beam position detecting apparatus;

first displacement amount computing apparatus for determining respective first displacement amounts, by which the position of the charged-particle beam is to be displaced by said first and second steering magnets, in accordance with detected signals outputted from said first and second beam position detecting apparatus; and

first cotrol system for controlling respective excitation currents of said first and second steering magnets in accordance with the respective first displacement amounts.

18. A particle therapy system according to claim 17, wherein said irradiation facility includes a first scatterer and a second scatterer arranged downstream of said first scatterer, and said first beam position detecting apparatus is arranged upstream of said second scatterer.

19. A particle therapy system according to claim 17, wherein said irradiation facility includes beam scanning apparatus for scanning the charged-particle beam, and said first beam position detecting apparatus is arranged upstream of said beam scanning apparatus.