Control system for a particle accelerator

Patent metadata

Field	Value
Publication number	US-9681531-B2
Application number	US-201314038967-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Sep 28, 2012
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

An example particle therapy system includes a particle accelerator to output a particle beam, where the particle accelerator includes: a particle source to provide pulses of ionized plasma to a cavity, where each pulse of the particle source has a pulse width corresponding to a duration of operation of the particle source to produce the corresponding pulse, and where the particle beam is based on the pulses of ionized plasma; and a modulator wheel having different thicknesses, where each thickness extends across a different circumferential length of the modulator wheel, and where the modulator wheel is arranged to receive a precursor to the particle beam and is configured to create a spread-out Bragg peak for the particle beam.

First claim

What is claimed is:

1. A particle therapy system comprising:
a particle accelerator to output a particle beam, comprising:
a particle source to provide pulses of ionized plasma to a cavity, each pulse of the particle source having a pulse width corresponding to a duration of operation of the particle source to produce the corresponding pulse, the particle beam being based on the pulses of ionized plasma; and
a modulator wheel having different thicknesses, each thickness extending across a different circumferential length of the modulator wheel, the modulator wheel being arranged to receive the particle beam and configured to create a spread-out Bragg peak for the particle beam;

one or more first input/output (I/O) modules operable at a first speed, the one or more first I/O modules being configured to send machine instructions to one or more motor controllers, at least one motor controller for controlling the modulator wheel; and
one or more second I/O modules operable at a second speed that is greater than the first speed, at least one of the second I/O modules being configured to send machine instructions to the particle source so that pulse widths of the particle source vary with rotational positions of the modulator wheel.

2. The particle therapy system of claim 1 , further comprising:
a therapy control computer programmed to receive prescription information from a hospital, to translate the prescription information to machine information, and to send treatment records to the hospital; and
a master control computer having a real-time operating system, the master control computer programmed to receive machine information from the therapy control computer, to translate the machine information into machine instructions, and to send the machine instructions to one or more of the first I/O modules and the second I/O modules.

3. The particle therapy system of claim 2 , further comprising an optical fiber over which are monitored a rotational speed and a position of the modulator wheel.

4. The particle therapy system of claim 1 , wherein the one or more first I/O modules comprise programmable logic controllers (PLC).

5. The particle therapy system of claim 4 , wherein at least one of the PLCs is programmed to send machine instructions to motor controllers for controlling a field shaping wheel system for shaping the particle beam prior to output.

6. The particle therapy system of claim 4 , wherein at least one of the PLCs is programmed to send machine instructions to a motor controller for controlling a scattering system for scattering the particle beam prior to output.

7. The particle therapy system of claim 4 , further comprising:
a radio frequency (RF) system to sweep RF frequencies through the cavity, the RF system comprising a rotating capacitor;
wherein at least one of the PLCs is programmed to send machine instructions to a motor controller that controls the rotating capacitor.

8. The particle therapy system of claim 1 , wherein a speed of the one or more first I/O modules is on the order of milliseconds and a speed of the one or more second I/O modules is on the order of one or more hundreds of nanoseconds.

9. The particle therapy system of claim 4 , further comprising:
a rotatable gantry on which the particle accelerator is mounted;
wherein at least one of the PLCs is programmed to send machine instructions to a motor controller that controls the rotatable gantry.

10. The particle therapy system of claim 4 , wherein two or more of the PLCs are configured to communicate with one another.

11. The particle therapy system of claim 1 , wherein the one or more second I/O modules comprise field-programmable gate arrays (FPGA).

12. The particle therapy system of claim 11 , further comprising:
a circuit board comprising a microprocessor;
at least one of the FPGAs being on the circuit board and in communication with the microprocessor;
wherein the microprocessor is programmed to communicate with a control computer.

13. The particle therapy system of claim 11 , further comprising:
a radio frequency (RF) system to sweep RF frequencies through the cavity to extract particles from a plasma column produced by the particle source;
wherein at least one of the FPGAs comprises an RF control module, the RF control module being configured to receive information about a rotation of the modulator wheel and, based thereon, to coordinate operational aspects of the particle source and the RF system.

14. The particle therapy system of claim 13 , wherein coordinating operational aspects of the particle source and the RF system comprises turning the particle source on or off based on a rotational position of the modulator wheel, and turning the RF system on or off based on a rotational position of the modulator wheel.

15. The particle therapy system of claim 14 , wherein the RF control module is further configured to send machine instruction to the particle source to turn-on when an RF voltage is at a certain frequency and to turn-off when the RF voltage is at a certain frequency.

16. The control system of claim 14 , wherein coordinating operational aspects of the particle source comprises specifying pulse widths during turn-on times of the particle source.

17. A particle therapy system comprising:
a particle accelerator to output a particle beam, comprising:
a particle source to provide pulses of ionized plasma to a cavity, each pulse of the particle source having a pulse width corresponding to a duration of operation of the particle source to produce the corresponding pulse, the particle beam being based on the pulses of ionized plasma; and
a modulator wheel having different thicknesses, each thickness extending across a different circumferential length of the modulator wheel, the modulator wheel being arranged to receive the particle beam and being configured to create a spread-out Bragg peak for the particle beam;

wherein the modulator wheel, as configured, produces different spread-out Bragg peaks at different depths within a patient, the different spread-out Bragg peaks deviating from predefined spread-out Bragg peak for the modulator wheel for a given depth application in the patient; and
wherein the particle therapy system is configured so that, for different depth applications within the patient, pulse widths of the particle source vary with rotational positions of the modulator wheel in order to produce spread-out Bragg peaks that approximate the predefined spread-out Bragg peak.

18. The particle therapy system of claim 17 , further comprising:
a therapy control computer programmed to receive prescription information from a hospital, to translate the prescription information to machine information, and to send treatment records to the hospital; and
a master control computer programmed to receive machine information from the therapy control computer, to translate the machine information into machine instructions, and output the machine instructions to control at least some operation of the particle therapy system.

19. The particle therapy system of claim 17 , further comprising an optical fiber over which are monitored a rotational speed and position of the modulator wheel.

20. The particle therapy system of claim 17 , further comprising programmable logic controllers (PLC).

21. The particle therapy system of claim 20 , wherein at least one of the PLCs is programmed to send machine instructions to a motor controller for controlling a field shaping wheel system for shaping the particl

Assignees

• Mevion Medical Systems Inc

Inventors

• Gall Kenneth P
• Rosenthal Stanley
• Sobczynski Thomas C
• Molzahn Adam C

Classifications

• A61N5/1077

  Beam delivery systems · CPC title

• H05H13/02 Primary

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

• H05H2007/004

  for modifying beam energy, e.g. spread out Bragg peak devices · CPC title

• A61N5/1065

  Beam adjustment · CPC title

• A61N2005/1095

  Elements inserted into the radiation path within the system, e.g. filters or wedges · CPC title