Method and system for electron radiotherapy

Patent metadata

Field	Value
Publication number	US-9711253-B2
Application number	US-201113989806-A
Country	US
Kind code	B2
Filing date	Nov 28, 2011
Priority date	Nov 28, 2010
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A radiotherapy system is disclosed. The radiotherapy system comprises an electron beam generator for generating an electron beam and a magnetic field generator for generating a magnetic field. In some embodiments of the present invention, the system further comprises a controller for controlling the electron beam and the magnetic field generators such that the electron beam is dynamically shifted and the magnetic field is dynamically redirected synchronously with the shifting.

First claim

What is claimed is:

1. A radiotherapy system, comprising:
an electron beam generator, for generating an electron beam, at an energy of at least 60 MeV, directed to a surface of a living body to propagate in said living body;
at least two coils, for generating a multipole magnetic field within said living body; and
a controller having a circuit configured for controlling said at least two coils to generate and to dynamically redirect the multipole magnetic field, by applying an alternating current to the at least two coils; the multipole magnetic field concentrates said electron beam while electrons of said beam propagate in said living body, and wherein the controller having the circuit is configured for controlling said electron beam generator to dynamically shift said electron beam;
wherein said shifting of the electron beam with the electron beam generator and said redirecting of the magnetic field with the at least two coils occurs synchronously and results in the delivery of an energy-dose into said living body with an energy-dose peak at an internal target location which is at a depth of at least 7 cm in said living body;
wherein said controller is configured to control said electron beam and said at least two coils such that said energy-dose has a symmetric profile with respect to each of an x, y and z axis.

2. The system according to claim 1 , further comprising a multileaf collimator for establishing said shifting.

3. The system according to claim 1 , wherein said multipole magnetic field is selected from the group consisting of a quadrupole magnetic field, a hexapole magnetic field and an octupole magnetic field.

4. The system according to claim 1 , wherein said energy-dose is higher by at least 50 percent from an energy-dose delivered by said beam to a surface of said living body upon entry thereto.

5. The system according to claim 1 , wherein said target location is located at least 12 centimeters below a surface of said living body.

6. The system according to claim 1 , wherein said target location is at most 50 cubic centimeters.

7. The system according to claim 1 , wherein said beam has a cross-sectional area of at least 15 square centimeters.

8. The system according to claim 1 , wherein said at least two coils have a symmetry axis arranged to receive a living body therebetween such that symmetry axes of said coils do not intersect with said body.

9. The system according to claim 1 , wherein said at least two coils have a symmetry axis arranged to receive a living body therebetween such that symmetry axes of said coils intersect with said body.

10. The system according to claim 1 , wherein said at least two coil comprise four coils or magnets having a symmetry axis arranged to receive a living body such that a first pair of coils or magnets is at one side of said body and a second pair of coils or magnets is at an opposite side of said body, and wherein symmetry axes of said coils or magnets are at an angle to each other.

11. The system according to claim 1 , wherein said at least two coils comprise four coils or magnets having a symmetry axis arranged to receive a living body such that a first pair of coils or magnets is at one side of said body and a second pair of coils or magnets is at an opposite side of said body, and wherein symmetry axes of said coils or magnets intersect with said body.

12. The system according to claim 1 , wherein said at least two coils comprise four coils or magnets having a symmetry axis arranged to receive a living body such that said coils or magnets are distributed around said body, wherein symmetry axes of said coils or magnets intersect with said body.

13. The system according to claim 1 , wherein said at least two coils comprise six coils or magnets having a symmetry axis arranged to receive a living body such that a first triplet of coils or magnets is at one side of said body and a second triplet of coils or magnets is at an opposite side of said body, and wherein for each triplet, a symmetry axis of a middle coil or magnet of said triplet is generally orthogonal to symmetry axes of the other two coils or magnets of said triplet.

14. A method of radiotherapy, comprising operating the system according to claim 1 , so as to deliver an effective amount of damaging radiation to an internal target tissue in a living body.

15. The system according to claim 1 , wherein said controller is configured to effect an alternate shifting of said beam generally parallel to itself and an alternate inversion of a direction of said magnetic field along an axis generally perpendicular to both the beam direction and the direction of the shift.

16. The system according to claim 1 , wherein said controller is configured for controlling said electron beam and said at least two coils using alternating current that is synchronized with pulses of electrons in said electron beam.

17. A method of radiotherapy, comprising:
generating an electron beam from an electron beam generator;
directing the electron beam at an energy of at least 60 MeV to a surface of a living body to propagate in said living body;
generating, with at least two coils, a multipole magnetic field within said living body, while electrons of said beam propagate within said living body;
controlling said at least two coils to concentrate said electron beam by applying an alternating current to said at least two coils; wherein the alternating current is synchronized with a plurality of pulses of electrons in said electron beam; and
dynamically shifting said electron beam with the electron beam generator and, synchronously with said shifting, dynamically redirecting said magnetic field with the at least two coils;
wherein said shifting said electron beam and said redirecting said magnetic field results in the delivery of an energy-dose having a symmetric profile with respect to each of an x, y and z axis into said living body with an energy-dose peak at an internal target location which is at a depth of at least 7 cm in said living body.

18. The method according to claim 17 , wherein said shifting is by a multileaf collimator.

19. The method according to claim 17 , wherein at least one of strength of said magnetic field, a cross-sectional area of said beam, an extent and rate of said shifting, and an extent and rate of said redirecting is selected such as to deliver an energy-dose to an internal target location in a living body.

Assignees

• Alezra Dror
• Nardi Eran
• Koren Sion
• Orion Itzhak
• Tel Hashomer Medical Res Infrastructure & Services Ltd
• Ben-Gurion Univ Of The Negev Res And Dev Authority

Inventors

• Alezra Dror
• Nardi Eran
• Koren Sion
• Orion Itzhak

Classifications

• A61N5/1042 Primary

  with spatial modulation of the radiation beam within the treatment head · CPC title

• A61N2005/1089

  Electrons · CPC title

• G21K1/093 Primary

  by magnetic means · CPC title

• A61B5/05

  Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves (measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24) · CPC title

• A61N5/1043

  Scanning the radiation beam, e.g. spot scanning or raster scanning · CPC title