Inner gantry

Patent metadata

Field	Value
Publication number	US-10279199-B2
Application number	US-201815896458-A
Country	US
Kind code	B2
Filing date	Feb 14, 2018
Priority date	Nov 18, 2005
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A system includes a patient support and an outer gantry on which an accelerator is mounted to enable the accelerator to move through a range of positions around a patient on the patient support. The accelerator is configured to produce a proton or ion beam having an energy level sufficient to reach a target in the patient. An inner gantry includes an aperture for directing the proton or ion beam towards the target.

First claim

What is claimed is:

1. A system comprising:
a patient support to hold a patient;
a synchrocyclotron to produce a proton or ion beam having an energy level sufficient to reach a target in the patient, the energy level being at least 150 MeV;
a gantry on which the synchrocyclotron is mounted to move the synchrocyclotron through a range of positions around the patient on the patient support; and
scanning elements that act on the proton or ion beam output from the synchrocyclotron, the scanning elements being between the patient and a location at which the proton or ion beam exits the synchrocyclotron.

2. The system of claim 1 , wherein the synchrocyclotron comprises ferromagnetic pole faces that define a space in which to accelerate particles to produce the proton or ion beam; and
wherein the synchrocyclotron comprises an extraction channel to output the proton or ion beam from the synchrocyclotron.

3. The system of claim 2 , wherein the ferromagnetic pole faces comprises two ferromagnetic pole faces, each of the ferromagnetic pole faces being associated with a respective superconducting coil for carrying current to generate a magnetic field in the space to cause the particles in the space to travel in a spiral path that increases in radius as the particles move around the space prior to output to the extraction channel.

4. The system of claim 3 , wherein each of the ferromagnetic pole faces comprises a pole face configured to shape the magnetic field so that a field index is kept positive to maintain weak focusing within the space.

5. The system of claim 1 , wherein the synchrocyclotron comprises superconducting coils for carrying current to generate a magnetic field in a space to cause particles to travel in a spiral path; and
wherein the synchrocyclotron comprises a helium-based cooling system to cool the superconducting coils to a superconducting temperature.

6. The system of claim 1 , wherein the synchrocyclotron comprises:
superconducting coils to generate a magnetic field to support production of the proton or ion beam;
a cold mass holding the superconducting coils; and
straps to support the cold mass during movement of the gantry.

7. The system of claim 6 , wherein the synchrocyclotron comprises:
an enclosure around the cold mass; and
straps to support the cold mass within the enclosure during movement of the gantry, each of the straps comprising two links, a first of the two links connecting to the enclosure, and a second of the two links connecting to the cold mass.

8. The system of claim 7 , wherein the two links comprise a fiberglass link.

9. The system of claim 1 , wherein the synchrocyclotron is configured to produce a maximum magnetic field between 6 Tesla (T) and 20 T, and wherein the energy level is between 150 MeV and 300 MeV.

10. A system comprising:
a patient support to hold a patient;
a synchrocyclotron to produce a proton or ion beam having an energy level sufficient to reach a target in the patient; and
a gantry on which the synchrocyclotron is mounted to move the synchrocyclotron through a range of positions around the patient on the patient support;
wherein the synchrocyclotron comprises:
superconducting coils to generate a magnetic field;
ferromagnetic pole faces to shape the magnetic field through a space in which particles are accelerated to form the proton or ion beam;
a cryostat to maintain the superconducting coils at a superconducting temperature; and
straps to support the cryostat, the straps being arranged based on gravitational force on the superconducting coils caused by rotation of the gantry.

11. The system of claim 10 , wherein the synchrocyclotron comprises an extraction channel to output the proton or ion beam from the synchrocyclotron.

12. The system of claim 11 , wherein the ferromagnetic pole faces comprises two ferromagnetic pole faces, each of the ferromagnetic pole faces being associated with a respective superconducting coil for carrying current to generate a magnetic field in the space to cause the particles in the space to travel in a spiral path that increases in radius as the particles move around the space prior to output to the extraction channel.

13. The system of claim 12 , wherein each of the ferromagnetic pole faces comprises a pole face configured to shape the magnetic field so that a field index is kept positive to maintain weak focusing within the space.

14. The system of claim 10 , wherein the synchrocyclotron comprises a helium-based cooling system to cool the superconducting coils to a superconducting temperature.

15. The system of claim 10 , further comprising:
at least one scatterer in a path of the proton or ion beam between the synchrocyclotron and the patient.

16. The system of claim 15 , wherein each of the straps comprises two links, a first of the two links connecting to an enclosure around the cryostat, and a second of the two links connecting to the cryostat.

17. The system of claim 16 , wherein the two links comprise a fiberglass link.

18. The system of claim 10 , wherein the synchrocyclotron is configured to produce a maximum magnetic field between 6 Tesla (T) and 20 T, and wherein the energy level is between 150 MeV and 300 MeV.

19. The system of claim 10 , wherein the synchrocyclotron weighs less than 40 Tons and occupies a volume of less than 4.5 cubic meters.

20. The system of claim 10 , wherein the gantry comprises two arms, each of the two arms supporting a different side of the synchrocyclotron to rotate the synchrocyclotron through a range of positions around the patient on the patient support.

21. The system of claim 1 , wherein the synchrocyclotron comprises:
superconducting coils to generate a magnetic field;
ferromagnetic pole faces to shape the magnetic field through a space in which particles are accelerated to form the proton or ion beam;
a cryostat to maintain the superconducting coils at a superconducting temperature; and
straps to support the cryostat, the straps being arranged based on gravitational force on the superconducting coils caused by rotation of the gantry.

Assignees

• Mevion Medical Systems Inc

Inventors

• Gall Kenneth P
• Rosenthal Stanley J
• Row Gordon D
• Ahearn Michael J

Classifications

• A61N5/1081 Primary

  Rotating beam systems with a specific mechanical construction, e.g. gantries · CPC title

• H05H13/02

  Synchrocyclotrons, i.e. frequency modulated cyclotrons · CPC title

• H05H13/04

  Synchrotrons · CPC title

• A61N5/10

  X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy (A61N5/01 takes precedence) · CPC title

• A61N2005/1087

  Ions; Protons · CPC title