Therapeutic apparatus

Patent metadata

Field	Value
Publication number	US-10183176-B2
Application number	US-200913131390-A
Country	US
Kind code	B2
Filing date	Dec 4, 2009
Priority date	Dec 12, 2008
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

A therapeutic apparatus comprising: a magnetic resonance imaging system adapted for acquiring a set of magnetic resonance imaging data in an imaging zone, the magnetic resonance imaging system comprising a means for generating a magnetic field, —a guiding means adapted for guiding a beam of charged particles to a target zone within a subject, wherein the imaging zone comprises the target zone, a zone determination means adapted for determining the location of the target zone within the subject using the set of magnetic resonance imaging data, a trajectory calculation means adapted for calculating a trajectory of the beam using magnetic field data being descriptive of the magnetic field such that the calculated trajectory reaches the target zone, a control means adapted for controlling the guiding means using the calculated trajectory such that the beam follows the calculated trajectory.

First claim

The invention claimed is:

1. A therapeutic apparatus, comprising:
a magnetic resonance imaging (MRI) system for generating a magnetic field and magnetic field data descriptive of the magnetic field, and for acquiring MRI data in an imaging zone;
a guide for a guiding a beam of charged particles for therapy along a path, through the magnetic field, which directs the beam of charged particles for therapy to a target zone within a subject, wherein the target zone is within the imaging zone;
a zone locator for using the MRI data to determine a location of the target zone within the subject;
a trajectory calculator for calculating, using the magnetic field data, a calculated trajectory of the beam of charged particles for therapy along the path, through the magnetic field, which directs the beam of charged particles for therapy to the target zone,
wherein the MRI system is further configured to measure an actual trajectory of the beam of charged particles for therapy within the imaging zone using the MRI data; and
a controller configured to control the guide in response to the actual trajectory measured by the MRI system to guide the beam of charged particles for therapy to follow the calculated trajectory.

2. The therapeutic apparatus of claim 1 , wherein the guide comprises
charged particle optics for adjusting the path; and
an adjustable attenuator for modulating the energy of the charged particles of the beam.

3. The therapeutic apparatus of claim 1 , wherein the trajectory calculator calculates an energy loss of the beam charged particles for therapy within the subject, and adjusts the calculated trajectory using the energy loss.

4. The therapeutic apparatus of claim 3 , wherein the beam of charged particles for therapy includes charged particles that have a kinetic energy greater than or equal to the kinetic energy necessary for the Bragg-peak of the particle beam to be within the target zone, and
further comprising an adjustable attenuator for modulating the location of the Bragg-peak of the beam so that the Bragg-peak is within the target zone.

5. The therapeutic apparatus of claim 1 , wherein the MRI data is acquired at periodic intervals, the zone locator further configured using the MRI data to monitor internal motion of the subject along the path, and the trajectory calculator is further configured to compensate for the internal motion of the subject during calculation of the calculated trajectory.

6. The therapeutic apparatus of claim 1 , wherein the beam of charged particles for therapy comprises at least one of the following: protons, carbon nuclei, or atomic nuclei.

7. The therapeutic apparatus of claim 1 , wherein the zone locator receives planning data for planning therapy, confirms when the planning data satisfies a predetermined criterion using the MRI data, and when the planning data does not satisfy the predetermined criterion performs at least one of: halting the generation of the beam of charged particles for therapy, alerting an operator that the planning data is not accurate, adjusting the planning data, and receiving corrections to the planning data from the operator.

8. The therapeutic apparatus of claim 1 , further comprising a split magnet having at least two cylindrical sub magnets for generating the magnetic field, the axes of cylindrical symmetry of the two sub magnets are aligned and the mid-plane of the split magnet divides the two sub magnets, the split magnet has a central region about its axis of cylindrical symmetry, and a split zone between the two sub magnets and the imaging zone lies within the central region and is centered on the mid-plane,
wherein the beam of charged particles for therapy traverses the split zone, and the guide rotates about the axis of cylindrical symmetry of the split magnet.

9. A method for controlling a therapeutic apparatus including a magnetic resonance imaging (MRI) system, the method:
generating a magnetic field and magnetic field data descriptive of the magnetic field;
acquiring MRI data in an imaging zone;
determining a location of a target zone within a subject using the MRI data, wherein the target zone is located within the imaging zone;
calculating a calculated trajectory of a beam of charged particles for therapy along a path through the magnetic field which directs the beam of charged particles for therapy to the target zone using the magnetic field data;
using the MRI data to measure an actual trajectory of the beam of charged particles for therapy; and
in response to the actual trajectory measured using the MRI data, guiding the beam of charged particles for therapy along the path, through the magnetic field, which directs the beam of charged particles for therapy to the target zone by controlling the beam of charged particles for therapy to follow the calculated trajectory.

10. The method of claim 9 , further comprising:
calculating an energy loss of the beam of charged particles for therapy within the subject, and
adjusting the calculated trajectory using the energy loss.

11. The method of claim 9 , further comprising:
acquiring the MRI data at periodic intervals at a rate fast enough to monitor subject motion;
monitoring, using the MRI data, internal motion of the subject along the path; and
compensating for the internal motion of the subject during calculation of the calculated trajectory.

12. The method of claim 9 , further comprising controlling the beam to follow the calculated trajectory in order to correct for motion of the target zone and of the subject.

13. A computer readable non-transitory medium for storing computer readable code, which when executed by a computer performs a method of controlling a therapeutic apparatus including a magnetic resonance imaging (MRI) system, the method comprising acts of:
generating a magnetic field and magnetic field data descriptive of the magnetic field;
acquiring MRI data in an imaging zone;
determining a location of a target zone within a subject using the MRI data, wherein the target zone is located within the imaging zone;
calculating a calculated trajectory of a beam of charged particles for therapy along a path, through the magnetic field, which directs the beam of charged particles for therapy to the target zone using the magnetic field data;
using the MRI data to measure an actual trajectory of the beam of charged particles for therapy; and
in response to the actual trajectory measured using the MRI data, guiding the beam of charged particles along the path, through the magnetic field, which directs the beam of charged particles for therapy to the target zone by controlling the beam of charged particles for therapy to follow the calculated trajectory.

14. The system of claim 1 , wherein a pulse repetition frequency of the beam of charged particles for therapy is exactly equal to a resonance frequency of an MR signal generated by the MRI system from which the MRI data is acquired.

15. The system of claim 1 , wherein the MRI system is configured to measure the actual trajectory of the beam of charged particles for therapy using the MRI data by performing Blood Oxygen Level Dependent (BOLD) contrast functional imaging to detect a modulation of a resonance frequency in voxels through which the beam of charged particles for therapy passes which is produced by a root mean square (RMS) magnetic field around the beam of charged particles for therapy.

16. The system of claim 1 , wherein the MRI system is configured to measure the actual trajectory of the beam of charged particles for therapy using the MRI data by measuring a local decrease in T2 r

Assignees

• Kuhn Michael Harald
• Overweg Johannes Adrianus
• Koninklijke Philips Nv

Inventors

• Kuhn Michael Harald
• Overweg Johannes Adrianus

Classifications

• A61N2005/1087

  Ions; Protons · CPC title

• A61N2005/1055

  using magnetic resonance imaging [MRI] · CPC title

• A61N5/1042

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

• A61N5/1037

  taking into account the movement of the target, e.g. 4D-image based planning · CPC title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title