Magnetic resonance imaging and radiotherapy apparatus with at least two-transmit-and receive channels

Patent metadata

Field	Value
Publication number	US-11116418-B2
Application number	US-201113884005-A
Country	US
Kind code	B2
Filing date	Nov 2, 2011
Priority date	Nov 9, 2010
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

A therapeutic apparatus comprising a radiotherapy apparatus for treating a target zone and a magnetic resonance imaging system for acquiring magnetic resonance imaging data. The radiotherapy apparatus comprises a radiotherapy source for directing electromagnetic radiation into the target zone. The radiotherapy apparatus is adapted for rotating the radiotherapy source at least partially around the magnetic resonance magnet. The magnetic resonance imaging system further comprises a radio-frequency transceiver adapted for simultaneously acquiring the magnetic resonance data from at least two transmit-and-receive channels. The therapeutic apparatus further comprises a processor and a memory containing machine executable instructions for the processor. Execution of the instructions causes the processor to: calibrate the transmit-and-receive channels; acquire the magnetic resonance data; reconstruct a magnetic resonance image; register a location of the target zone in the image; and generate radiotherapy control signals using the registered image.

First claim

The invention claimed is:

1. A therapeutic apparatus comprising:
a radiotherapy apparatus for treating a target zone of a subject, wherein the radiotherapy apparatus comprises a radiotherapy source for directing a radiation beam into the target zone;
a magnetic resonance imaging system for acquiring magnetic resonance imaging data from an imaging zone, a subject support configured to support the subject with the target zone within the imaging zone, the subject support configured to move in three spatial directions and to rotate about an axis for each of those directions, allowing for free placement of a subject;
the magnetic resonance imaging system including a magnet for generating a magnetic field within the imaging zone defined in an inner bore of the magnet, wherein the radiotherapy apparatus is configured to rotate the radiotherapy source peripherally around the magnet and the subject supported in the target zone,
wherein the magnetic resonance imaging system does not comprise a radio frequency volume body coil mounted in the inner bore around the imaging zone, wherein the inner bore is at least 80 cm in diameter;
the magnetic resonance imaging system including
a split gradient coil disposed in the inner bore with a gap through which a path of the radiation beam passes as the radiotherapy source rotates peripherally around the subject, and
at least two local radio-frequency transmit and receive channels positioned avoiding the path of the radiation beam generated by the radiotherapy source as the radiotherapy source rotates peripherally around the subject, the at least two local radio frequency transmit and receive channels being supported by at least one of the subject and the support, and configured to independently exclusively transmit radio frequency fields into the imaging zone for exciting and manipulating an orientation of magnetic spins in the imaging zone and to acquire the magnetic resonance data from the imaging zone,
wherein the two local radio frequency transmit-and-receive channels are positioned to maintain a peripheral gap therebetween such that the channels avoid the path of the radiation beam as the radiation source rotates peripherally around the subject.

2. The therapeutic apparatus of claim 1 , wherein the radiotherapy source rotates about an axis of rotation, wherein the subject support is configured to position the target zone in the imaging zone on the axis of rotation.

3. The therapeutic apparatus of claim 1 , wherein the at least two local transmit-and-receive channels comprise flexible coil elements.

4. The therapeutic apparatus of claim 1 , wherein the radiotherapy apparatus comprises a light source configured to illuminate a portion of the subject that is descriptive of the path of the radiation beam generated by the radiotherapy source.

5. The therapeutic apparatus of claim 1 , wherein the at least two local radiofrequency transmit-and-receive channels include a first local transmit-and-receive channel and a second local transmit-and-receive channel and further including:
a first transceiver connected with the first local transmit-and-receive channel; and
a second transceiver, different from the first transceiver, connected with the second local transmit-and-receive channel;
the first and second transceivers being connected with a processor to independently convey instructions to transmit the radio frequency excitation fields to the first and second local transmit-and-receive channels and to convey the magnetic resonance data to the processors.

6. The therapeutic apparatus of claim 1 , wherein the at least two local transmit-and-receive channels include a first flexible local coil and a second flexible local coil, the first and second flexible local coils configured to be positioned around torso portions of a patient separated by the peripheral gap through which the radiation beam passes.

7. The therapeutic apparatus of claim 1 , further comprising:
a processor configured to control the therapeutic apparatus and the magnetic resonance imaging apparatus;
a memory containing machine executable instructions for execution by the processor, wherein execution of the instructions causes the processor to:
perform a pre-scan calibration using the at least two local transmit-and-receive channels of the magnetic imaging system;
acquire the magnetic resonance data in accordance with the pre-scan calibration using the at least two transmit-and-receive channels;
reconstruct a magnetic resonance image from the magnetic resonance data;
register a location of the target zone in the magnetic resonance image;
generate radiotherapy control signals in accordance with the location of the target zone, wherein the radiotherapy control signals cause the radiotherapy source to irradiate the target zone with the radiation beam; and
send the radiotherapy control signals to the radiotherapy system.

8. The therapeutic apparatus of claim 7 , wherein each of the local transmit-and-receive channels has multiple coil elements, wherein execution of the instructions further causes the processor to calibrate transmit amplitudes and phases and receive amplitudes and phases for the multiple coil elements during the pre-scan calibration.

9. The therapeutic apparatus of claim 7 , wherein execution of the instructions further causes the processor to:
repeatedly acquire the magnetic resonance data during the irradiation of the target zone, reconstruct the magnetic resonance image, and register the location of the target zone during irradiation of the target zone; and
repeatedly generate and send updated radiotherapy control signals, wherein the updated radiotherapy control signals compensate for motion of the subject between subsequent acquisitions of the magnetic resonance data, wherein the updated radiotherapy control signals are sent to the radiotherapy source during irradiation of the target zone.

10. The therapeutic apparatus of claim 9 , wherein the radiotherapy source comprises an adjustable beam collimator, wherein the updated radiotherapy control signals comprises commands for controlling the beam collimator.

11. The therapeutic apparatus of claim 9 , wherein the magnet is a cylindrical super conducting magnet, wherein the magnet has a recess in an outer wall, wherein the radiotherapy apparatus is adapted for rotating the radiotherapy source around the recess, and wherein at least a portion of the radiotherapy source is within the recess.

12. A non-transitory, computer program product comprising machine executable instructions for execution by a processor of a therapeutic apparatus; wherein the therapeutic apparatus comprises a radiotherapy apparatus for treating a target zone of a subject;
wherein the radiotherapy apparatus comprises a radiotherapy source for directing a radiation beam into the target zone and a magnetic resonance imaging system for acquiring magnetic resonance imaging data from an imaging zone;
a subject support configured to support the subject with the target zone within the imaging zone, the subject support configured to move in three spatial directions and to rotate about an axis for each of the three spatial directions, allowing for free placement of a subject, the magnetic resonance imaging system including a cylindrical magnet for generating a magnetic field within the imaging zone defined in an inner bore of the magnet, wherein the radiotherapy apparatus is adapted for rotating the radiotherapy source around the magnet, the magnetic resonance imaging system including at least two local radio-frequency transmit and receive channels positioned avoiding a path of the radiation beam generated by the radiotherapy source, the at least tw

Assignees

• Harvey Paul Royston
• Koninklijke Philips Nv

Inventors

• Harvey Paul Royston

Classifications

• A61B5/0037 Primary

  Performing a preliminary scan, e.g. a prescan for identifying a region of interest · CPC title

• A61N5/1049

  for verifying the position of the patient with respect to the radiation beam · CPC title

• G01R33/4812

  MR combined with X-ray or computed tomography [CT] · CPC title

• A61N2005/1056

  by projecting a visible image of the treatment field · CPC title

• A61N2005/1055

  using magnetic resonance imaging [MRI] · CPC title