CONFIGURABLE RADIOTHERAPY COUCH TOP FOR MAGNETIC RESONANCE RADIOTHERAPY SIMULATION

Abstract

Disclosed herein is a medical system (400) comprising a magnetic resonance imaging system (402) configured for acquiring magnetic resonance imaging data (444, 444′) from a subject (418) within an imaging zone (408). The medical system further comprises a subject support (100) configured for supporting at least a portion of the subject within the imaging zone, wherein the subject support comprises a radiotherapy couch top (102) 5 configured for receiving the subject. The radiotherapy couch top comprises a flat surface (104) configured for supporting the subject. The radiotherapy couch top further comprises a head support region (110) configured for receiving a head of the subject, wherein the head region comprises a depression (108). The head region is configured for receiving a flat head support plate (112). The medical system further comprises a flat head support plate. The flat head support plate is configured to form part of the flat surface (104′) when installed in the head region.

Claims

1. A medical system comprising: a magnetic resonance imaging system configured for acquiring magnetic resonance imaging data from a subject within an imaging zone; a subject support configured for supporting at least a portion of the subject within the imaging zone, wherein the subject support comprises a radiotherapy couch top configured for receiving the subject, wherein the radiotherapy couch top comprises a flat surface configured for supporting the subject, wherein the radiotherapy couch top further comprises a head support region configured for receiving a head of the subject, wherein the head region comprises a depression, and wherein the head region is configured for receiving a flat head support plate; and a flat head support plate, wherein the flat head support plate is configured to form part of the flat surface when installed in the head region wherein the flat head support plate comprises radiotherapy mask attachment fixtures; wherein the flat head support plate is installed in the head region, wherein the medical system further comprises a memory for storing machine executable instructions and pulse sequence commands, wherein the pulse sequence commands are configured to control the magnetic resonance imaging system to acquire the magnetic resonance imaging data, wherein the medical system further comprises a processor for controlling the medical system, wherein execution of the machine executable instructions causes the processor to: control the magnetic resonance imaging system with the pulse sequence commands to acquire the magnetic resonance imaging data; reconstruct at least one magnetic resonance image using the magnetic resonance imaging data; and generate radiation therapy planning data using the at least one magnetic resonance image

2. (canceled)

3. The medical system of claim 1, wherein the depression is configured for mounting a magnetic resonance imaging head coil.

4. The medical system of claim 3, wherein the medical system comprises the magnetic resonance imaging head coil.

5. The medical system of claim 1, wherein generation of the radiotherapy planning data comprises applying an organ contouring algorithm to the at least one magnetic resonance image to generate an organ segmentation.

6. The medical system claim 1, wherein the pulse sequence commands are configured for at least partially acquiring the magnetic resonance imaging data according to a diffusion weighted magnetic resonance imaging protocol, wherein generation of the radiotherapy planning data comprises reconstructing the at least one magnetic at least one diffusion weighted magnetic resonance image for radiotherapy dose sculpting.

7. The medical system claim 1, wherein execution of the machine executable instructions further causes the processor to: receive a radiotherapy treatment plan; and generate radiotherapy treatment system control commands a using the radiotherapy treatment plan, the radiotherapy planning data, and a radiotherapy system model.

8. The medical system of claim 1, wherein execution of the machine executable instructions further causes the processor to reconstruct at least one pseudo CT images using the magnetic resonance imaging data, wherein the pulse sequence commands are configured to acquire the magnetic resonance imaging data according to any one of the following: according to an ultrashort echo time magnetic resonance imaging protocol, according to a T1 weighted magnetic resonance imaging protocol, according to a T2 weighted magnetic resonance imaging protocol, and combinations thereof.

9. The medical system of claim 1, wherein the radiotherapy couch top is rigid.

10. A method of operating a medical system, wherein the medical system comprises a magnetic resonance imaging system configured for acquiring magnetic resonance imaging data from a subject within an imaging zone, wherein the medical system further comprises a subject support configured for supporting at least a portion of the subject within the imaging zone, wherein the subject support comprises a radiotherapy couch top configured for receiving the subject, wherein the radiotherapy couch top comprises a flat surface (104), wherein the radiotherapy couch top further comprises a head support region configured for receiving a head of the subject, wherein the head region comprises a depression, wherein the head region is configured for receiving a flat head support plate, wherein the flat head support plate comprises radiotheraphy mask attachment features wherein the method comprises: installing the flat head support plate, wherein the flat head support plate is configured to form part of the flat surface when installed in the head region; controlling the magnetic resonance imaging system with pulse sequence commands to acquire the magnetic resonance imaging data; and generate radiation therapy planning data using the at least one magnetic resonance image.

11. The method of claim 10, wherein the depression is configured for receiving a magnetic resonance imaging head coil wherein the method further comprises; removing the flat head support plate; installing the magnetic resonance imaging head coil in the depression; and controlling the magnetic resonance imaging system with pulse sequence commands to acquire the magnetic resonance imaging data using the head coil.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In the following preferred embodiments of the invention will be described, by way of example only, and with reference to the drawings in which:

[0045] FIG. 1 illustrates an example of a radiotherapy couch top mounted to a subject support of a magnetic resonance imaging system;

[0046] FIG. 2 illustrates an example of a flat head support plate;

[0047] FIG. 3 shows a further view of the radiotherapy couch top and subject support of FIG. 1;

[0048] FIG. 4 illustrates an example of a medical system;

[0049] FIG. 5 shows a flow chart which illustrates a method of operating the medical system of FIG. 4;

[0050] FIG. 6 shows a further view of the medical system of FIG. 4,

[0051] FIG. 7 shows a flow chart which illustrates a method of operating the medical system as configured in FIG. 6; and

[0052] FIG. 8 shows a flow chart which illustrates a further method of operating the medical system illustrated in FIGS. 4 and 6.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] Like numbered elements in these figures are either equivalent elements or perform the same function. Elements which have been discussed previously will not necessarily be discussed in later figures if the function is equivalent.

[0054] Medical imaging may be used as a basis for treatment planning in external beam radiotherapy. In radiotherapy devices (such as Linear accelerators), the patient table (radiotherapy couch top) is flat and equipped with indexing for patient positioning devices while in diagnostic imaging MR scanners the patient tables typically are not flat (e.g curved form is often used). When using MR scanner for radiotherapy simulation (imaging) the curved table top is replaced by the flat table top.

[0055] The receive coils and other accessories of the MR scanner are typically designed for the curved form table. While the receive coils and accessories are designed for other table form (curved) they cannot be optimally used with the flat table.

[0056] FIG. 1 depicts an example of a subject support 100 for a magnetic resonance imaging system. The subject support 100 has a radiotherapy couch top 102 that has been installed in the top. The radiotherapy couch top 102 is an insert for the subject support 100 that is fixed into place and replicates a radiotherapy couch top as would be used for a radiotherapy system. The radiotherapy couch top 102 has a flat surface 104 and an indexing system 106. In this example the indexing system is a collection of two rows of parallel holes or mounts to which fixtures can be attached. The use of such holes or fixtures is typical. In other examples the index system 106 may be two railings or rails to which fixtures may be attached that on either sides of the flat surface 104.

[0057] It can be seen in this example that there is a depression 108 or coil receptacle in a head support region 110. The drawing depicts a flat head support plate 112 that may be installed into the subject support 100 so that the depression 108 is covered. The flat head support plate 112 also has a flat surface 104′ that forms part of the flat surface 104 when it is installed.

[0058] FIG. 2 illustrates an alternative flat head support plate 112. The flat head support plate 112 in FIG. 2 may be used to replace the flat head support plate 112 depicted in FIG. 1. The flat head support plate 112 in FIG. 2 is similar to the flat head support plate 112 in FIG. 1 with the exception of a number of radiotherapy mask attachment fixtures 200. In this example the radiotherapy mask attachment fixtures 200 are two rows of poles which may be threaded or configured for receiving a mount. For example a radiotherapy mask or S-type mask may be fixed to the flat head support plate 112.

[0059] FIG. 3 shows a further view of the magnetic resonance imaging support 100 depicted in FIG. 1. In the diagram in FIG. 3 the flat head support plate 112 is not shown. Instead there is a magnetic resonance imaging head coil 300 which can be installed into the depression 108 or coil receptacle. From FIGS. 1 and 3 it is very clear that the subject support 100 can be very quickly and easily switched between two configurations. The configuration for FIG. 1 may be used for radiation therapy simulation. The configuration depicted in FIG. 3 may be used for conventional magnetic resonance imaging protocols. This may be achieved without the need to remove or replace the radiotherapy couch top 102.

[0060] In this example, the flat table top (flat surface 10) dedicated for Radio Therapy (RT) simulation imaging is equipped with the (curved) features (depression 108) which allow placing the diagnostic RF coils 300 or other accessories in optimal position. In case the RF coil is not needed for the application, the coil can be replaced by a filler piece.

[0061] The flat head support plate 112 functions as a filler piece. In case the RF coil is not needed for the application, the coil can be replaced by a filler piece to form a continuous flat surface that may be used for RT simulation.

[0062] FIG. 4 illustrates an example of a medical system 400. The medical system 400 comprises a magnetic resonance imaging system 402, the subject support 100 depicted in FIGS. 1 and 3, and a computer system 430.

[0063] The magnetic resonance imaging system 402 comprises a magnet 404. The magnet 404 is a superconducting cylindrical type magnet with a bore 406 through it. The use of different types of magnets is also possible; for instance it is also possible to use both a split cylindrical magnet and a so called open magnet. A split cylindrical magnet is similar to a standard cylindrical magnet, except that the cryostat has been split into two sections to allow access to the iso-plane of the magnet, such magnets may for instance be used in conjunction with charged particle beam therapy. An open magnet has two magnet sections, one above the other with a space in-between that is large enough to receive a subject: the arrangement of the two sections area similar to that of a Helmholtz coil. Open magnets are popular, because the subject is less confined. Inside the cryostat of the cylindrical magnet there is a collection of superconducting coils.

[0064] Within the bore 406 of the cylindrical magnet 404 there is an imaging zone 408 where the magnetic field is strong and uniform enough to perform magnetic resonance imaging. A field of view 409 is shown within the imaging zone 408. The magnetic resonance data that is acquired for the field of view 409. A subject 418 is shown as being supported by the subject support 100 such that a head region of the subject 418 is within the imaging zone 408 and the field of view 409.

[0065] Within the bore 406 of the magnet there is also a set of magnetic field gradient coils 410 which is used for acquisition of preliminary magnetic resonance data to spatially encode magnetic spins within the imaging zone 408 of the magnet 404. The magnetic field gradient coils 410 connected to a magnetic field gradient coil power supply 412. The magnetic field gradient coils 410 are intended to be representative. Typically magnetic field gradient coils 410 contain three separate sets of coils for spatially encoding in three orthogonal spatial directions. A magnetic field gradient power supply supplies current to the magnetic field gradient coils. The current supplied to the magnetic field gradient coils 410 is controlled as a function of time and may be ramped or pulsed.

[0066] Adjacent to the imaging zone 408 is a radio-frequency coil 414 for manipulating the orientations of magnetic spins within the imaging zone 408 and for receiving radio transmissions from spins also within the imaging zone 408. The radio frequency antenna may contain multiple coil elements. The radio frequency antenna may also be referred to as a channel or antenna. The radio-frequency coil 414 is connected to a radio frequency transceiver 416. The radio-frequency coil 414 and radio frequency transceiver 416 may be replaced by separate transmit and receive coils and a separate transmitter and receiver. It is understood that the radio-frequency coil 414 and the radio frequency transceiver 416 are representative. The radio-frequency coil 414 is intended to also represent a dedicated transmit antenna and a dedicated receive antenna. Likewise the transceiver 416 may also represent a separate transmitter and receivers. The radio-frequency coil 414 may also have multiple receive/transmit elements and the radio frequency transceiver 416 may have multiple receive/transmit channels. For example if a parallel imaging technique such as SENSE is performed, the radio-frequency could 414 will have multiple coil elements.

[0067] The subject support 100 is shown with the flat head support plate 112 installed. The subject 418 is reposing on the flat surface 104. A radiotherapy mask 420 is shown as restraining the head of the subject 418. The subject's 418 head is within the field of view 409. With the flat head support plate 112 installed the flat surface 104′ as depicted in FIGS. 1 and 2 form part of the flat surface 104.

[0068] The radio-frequency transmitter 416 and the magnetic field gradient coil power supply 412 are shown as being connected to a hardware interface 434 of computer system 430. The computer system 430 further comprises a processor 432 that is shown as being connected with the hardware interface 434, a user interface 436, and a memory 438. The processor 432 is intended to represent one or more processors that may be distributed in one or more computing systems. The memory 438 is also intended to represent any sort of memory or storage which is accessible to the processor 432.

[0069] The memory 438 is shown as containing machine-executable instructions 440. The machine-executable instructions 440 enable the processor 432 to control the operation and function of the medical system 400 as well as to perform basic data and image processing procedures. The memory 438 is further shown as containing pulse sequence commands 442. The pulse sequence commands 442 may represent one or more set of pulse sequence commands that may be used to control the magnetic resonance imaging system to acquire magnetic resonance imaging data. The pulse sequence commands may also be data which may be converted into such commands.

[0070] The memory 438 is further shown as containing magnetic resonance imaging data 444 that has been acquired by controlling the magnetic resonance imaging system 402 with the pulse sequence commands 442. The memory 438 is further shown as containing a magnetic resonance image 446 that has been reconstructed from the magnetic resonance imaging data 444. The magnetic resonance image 446 may represent two or three-dimensional image data and may represent multiple images.

[0071] The memory 438 is further shown as containing radiation therapy planning data 448. The radiation therapy planning data 448 is data which may be used for radiotherapy simulation. For example, the radiation therapy planning data 448 may be magnetic resonance images 446 which have been segmented and used to identify various regions of tissue for eradiation or to reduce the minimal amount of radiation exposure to.

[0072] The memory 438 is shown as further containing optional radiotherapy treatment plan 450. This for example may incorporate anatomical data and/or previously specified data which represents a region of the subject 418 to irradiate as well as possibly regions which are intended to not be irradiate or to reduce the amount of exposed radiation to. The memory 438 is shown as optionally containing a radiotherapy system model 452. The radiotherapy system model 452 may for example be used for simulating the behavior of a particular radiotherapy system.

[0073] The memory 438 is further shown as optionally containing radiotherapy system control commands 454 which were constructed using the radiation therapy planning data 448, the optional radiotherapy treatment plan 450, and the optional radiotherapy system model 452. The radiotherapy system control commands 454 may be actual commands for controlling the radiotherapy system modeled by the radiotherapy system model 452 to perform an eradiation of the subject 418. The features 450, 452, and 454 may be in a different distributed computer system. They may for example be incorporated into a radiotherapy system.

[0074] FIG. 5 illustrates a method of operating the medical system 400 of FIG. 4. It is noted that the method in FIG. 5 is performed with the flat head support plate 112 installed. First in step 500 the magnetic resonance imaging system 402 is controlled with the pulse sequence commands 442 to acquire the magnetic resonance imaging data 444. Next in step 502 the at least one magnetic resonance image 446 is reconstructed from the magnetic resonance imaging data 444. Next in step 504 the radiation therapy planning data 448 is reconstructed from the at least one magnetic resonance image 446. This for example may be achieved by an implementation of an organ contouring or segmentation algorithm.

[0075] FIG. 6 shows a further view of the medical system 400 of FIG. 4. In this example the flat head support plate 112 has been removed and instead the magnetic resonance imaging head coil 300 has been installed into the subject support 100. In the configuration illustrated in FIG. 6 the magnetic resonance imaging system 402 may be used for conventional clinical magnetic resonance imaging.

[0076] The memory 438 is again is shown as containing the machine-executable instructions 440. The memory 438 is shown as containing the pulse sequence commands 442′. These may be different pulse sequence commands than were illustrated in FIG. 4. The pulse sequence commands 442′ may also be referred to as second pulse sequence commands. The memory 438 is further shown as containing magnetic resonance imaging data 444′ that has been acquired by controlling the magnetic resonance imaging system 402 with the pulse sequence commands 442′. The magnetic resonance imaging data 444′ may also be referred to as second magnetic resonance imaging data. The memory 438 is shown as containing at least one magnetic resonance image 446′ that has been reconstructed from the magnetic resonance imaging data 444′. The magnetic resonance images 446′ may also be referred to as second magnetic resonance images.

[0077] FIG. 7 illustrates a method of operating the medical system 400 as is depicted in FIG. 6. The method in FIG. 7 may be executed when the magnetic resonance imaging head coil 300 is installed into the subject support 100. First in step 700 the magnetic resonance imaging system 402 is controlled with the pulse sequence commands 442′ to acquire the magnetic resonance imaging data 444′. Then, in step 702, the at least one magnetic resonance image 446′ is reconstructed using the magnetic resonance imaging data 444′.

[0078] FIG. 8 shows a flowchart which illustrates a method of operating and configuring the medical system 400 that is depicted in FIGS. 4 and 6. First in step 800 the flat head support plate 112 is installed into the subject support. Next in step 802, the magnetic resonance imaging system is controlled with the pulse sequence commands 442 to acquire the magnetic resonance imaging data 444. The pulse sequence commands 442 may be referred to as first pulse sequence commands and the magnetic resonance imaging data 444 may also be referred to as first magnetic resonance imaging data.

[0079] Next in step 804, the flat head support plate 112 is removed. Then in step 806 the magnetic resonance imaging head coil 300 is installed into the depression 108 or receptacle. Finally, in step 808, the magnetic resonance imaging system 402 is controlled with the pulse sequence commands 442′ to acquire the magnetic resonance imaging data 444′. Again, the pulse sequence commands 442′ may be referred to as second pulse sequence commands and the magnetic resonance imaging data 444′ may be referred to as second magnetic resonance imaging data.

[0080] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments.

[0081] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be construed as limiting the scope.

LIST OF REFERENCE NUMERALS

[0082] 100 subject support [0083] 102 radiotheraphy couch top [0084] 104 flat surface [0085] 104′ flat surface [0086] 106 index system [0087] 108 depression or coil recepticle [0088] 110 head support region [0089] 112 flat head support plate [0090] 200 radiotherapy mask attachment fixtures [0091] 300 magnetic resonance imaging head coil [0092] 400 medical system [0093] 402 magnetic resonance imaging system [0094] 404 magnet [0095] 406 bore of magnet [0096] 408 imaging zone [0097] 409 field of view [0098] 410 magnetic field gradient coils [0099] 412 magnetic field gradient coil power supply [0100] 414 radio-frequency coil [0101] 416 transceiver [0102] 418 subject [0103] 420 radiotherapy mask [0104] 430 computer [0105] 432 processor [0106] 434 hardware interface [0107] 436 user interface [0108] 438 memory [0109] 440 machine executable instructions [0110] 442 pulse sequence commands [0111] 442′ pulse sequence commands [0112] 444 magnetic resonance imaging data [0113] 444′ magnetic resonance imaging data [0114] 446 magnetic resonance image [0115] 446′ magnetic resonance image [0116] 448 radiation therapy planning data [0117] 450 radiotheraphy treatment plan [0118] 452 radiotherapy system model [0119] 454 radiotherapy system control commands [0120] 502 control the magnetic resonance imaging system with the pulse sequence commands to acquire the magnetic resonance imaging data [0121] 504 reconstruct at least one magnetic resonance image using the magnetic resonance imaging data [0122] 506 generate radiation therapy planning data using the at least one magnetic resonance image [0123] 700 control the magnetic resonance imaging system with the pulse sequence commands to acquire the magnetic resonance imaging data [0124] 702 reconstruct at least one magnetic resonance image using the magnetic resonance imaging data [0125] 800 installing the flat head support plate [0126] 802 controlling the magnetic resonance imaging system with pulse sequence commands to acquire the magnetic resonance imaging data [0127] 804 removing the flat head support plate [0128] 806 installing the magnetic resonance imaging head coil in the depression [0129] 808 controlling the magnetic resonance imaging system with pulse sequence commands to acquire the magnetic resonance imaging data using the head coil