X-ray and electron radiotherapy clinical treatment machine

• US 4,726,046 A
• Filed: 11/05/1985
• Issued: 02/16/1988
• Est. Priority Date: 11/05/1985
• Status: Expired due to Term

• Current Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Original Assignee: Varian Associates, Inc.
• Inventors: Nunan, Craig S.
• Primary Examiner(s): Howell, Janice A.
• Assistant Examiner(s): Porta, David P.
• Application Number:
  US06/795,373
• Time in Patent Office: 833 Days
• Field of Search: 378/65, 378/146, 250/492.3, 250/492.1
• US Class Current: 378/65
• CPC Class Codes: A61N 2005/1089 Electrons
• CPC Class Codes: A61N 5/1042 with spatial modulation of the radiation beam within the treatment head
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/1078 Fixed beam systems
• CPC Class Codes: A61N 5/1081 Rotating beam systems with a specific mechanical construction, e.g. gantries

Abstract

A radiotherapy machine includes a microwave powered accelerator to produce an energetic beam of charged particles, bending and focussing magnets to parallel scan the beam in a plane and collimators to make the resulting parallel scanned beam into paraxial rays of charged particles or X-rays. The beam is intensity modulated as it is scanned to control dosage spatial distribution. The subject is moved perpendicular to the scanning plane in order to treat a 3-dimensional shape.

Claims

1. A radiotherapy clinical treatment machine comprising:

a microwave accelerator means for producing a high velocity paraxial beam of charged particles of finite energy spread along a first axis;

a means for scanning the beam with time in a scanning plane defined as that containing a second and third axis of the beam;

such that the second axis of the scanned beam at a first time is parallel to the third axis of the scanned beam at any second time; and

a means for modulating the intensity of the beam while the beam is being scanned.

2. A machine as in claim 1 wherein said scanning plane also contains said first axis.

3. A machine as in claim 1 wherein said scanning plane does not contain said first axis.

4. A machine as in claim 3 wherein said means for scanning the beam includes means for producing a magnetic field perpendicular to said first axis.

5. A machine as in claim 4 wherein said means for producing a magnetic field includes means for mechanically rotating said means for producing a magnetic field.

6. A machine as in claim 4 wherein said means for producing a magnetic field includes means for varying the field with time.

7. A machine as in claim 3 including means for producing a paraxial beam of X-rays from the beam of charged particles as the beam of charged particles is scanned, the paraxial beam of X-rays at a first time being parallel to the paraxial beam of X-rays at any second time.

8. A machine as in claim 4 including means for producing a paraxial beam of X-rays from the beam of charged particles as the beam of charged particles is scanned, the paraxial beam of X-rays at a first time being parallel to the paraxial beam of X-rays at any second time.

9. A machine as in claim 5 including means for producing a paraxial beam of X-rays from the beam of charged particles as the beam of charged particles is scanned, the paraxial beam of X-rays at a first time being parallel to the paraxial beam of X-rays at any second time.

10. A machine as in claim 6 including means for producing a paraxial beam of X-rays from the beam of charged particles as the beam of charged particles is scanned, the paraxial beam of X-rays at a first time being parallel to the paraxial beam of X-rays at any second time.

11. A machine as in claim 7 wherein said means for producing a paraxial beam of X-rays includes a collimator.

12. A machine as in claim 8 wherein said means for producing a paraxial beam of X-rays includes a collimator.

13. A machine as in claim 9 wherein said means for producing a paraxial beam of X-rays includes a collimator.

14. A machine as in claim 10 wherein said means for producing a paraxial beam of X-rays includes a collimator.

15. A machine as in claim 13 wherein said means for producing a paraxial beam of X-rays includes a bow-tie magnet.

17. A machine as in claim 15 wherein said means for producing a paraxial beam of X-rays includes a collimator.

18. A machine as in claims 11, 12, 13, 14 or 16 including means for progressively reducing a cross-sectional dimension of the paraxial beams of X-rays from a side opposite to a direction of scan.

19. A machine as in claims 11, 12, 13, 14 or 16 including means attached to said collimator for progressively reducing a cross-sectional dimension of the paraxial beam of X-rays from a side parallel to a direction of beam scan.

16. A radiotherapy clinical treatment machine comprising:

a microwave accelerator means for producing a paraxial beam of electrons of finite energy spread having mean energy of at least 1 MeV;

means for forming the beam of electrons into a narrowly collimated beam;

means for scanning as a function of time the narrowly collimated beam of electrons in a plane such that the axis of a narrowly collimated beam of electrons at a first time is parallel to the axis of a narrowly collimated beam of electrons at any second time.

20. A radiotherapy clinical treatment machine comprising:

a microwave accelerator means for producing a paraxial beam of electrons of finite energy spread having mean energy of at least 1 MeV;

an X-ray target means for converting the energy of the electron beam produced by said accelerator into X-rays;

means for forming the beam of X-rays into a narrowly collimated beam of X-rays having small penumbra;

means for scanning as a function of time the narrowly collimated beam of X-rays in a plane such that the axis of a narrowly collimated beam of X-rays at a first time is parallel to the axis of a narrowly collimated beam of X-rays at any second time.