WO2007020212A1

WO2007020212A1 - Treatment station for particle bombardment of a patient and a particle therapy installation

Info

Publication number: WO2007020212A1
Application number: PCT/EP2006/065128
Authority: WO
Inventors: Sven Oliver GRÖZINGER; Eike Rietzel; Tim Use
Original assignee: Siemens AG; Siemens Corp
Current assignee: Siemens AG; Siemens Corp
Priority date: 2005-08-12
Filing date: 2006-08-08
Publication date: 2007-02-22
Anticipated expiration: 2008-02-12
Also published as: US7812326B2; ATE504926T1; EP1752992A1; DE602006021190D1; US20080191152A1; EP1913603A1; EP1913603B1

Abstract

The invention relates to a treatment Station (15) for particle bombardment of a patient, having an apparatus (3) for adaptation of at least one particle beam parameter of a particle beam (10; 10A; 10B; 10C) of a particle therapy installation (1). The treatment Station is designed for Operation in at least two operating modes, with the treatment Station being operable in a first operating mode with a first particle type and in a second operating mode with a second particle type. The apparatus has at least one first beamforming element (21; 23; 33; 42), which is held by a holding unit (25; 35; 41), with the beamforming element (21; 23; 33; 42) being designed for adaptation of the particle beam parameter and the holding unit (25; 35; 41) being designed for positioning of the first beamforming element (21; 23; 33; 42) as a function of the operating mode, in such a manner that the first beamforming element (21; 23; 33; 42) can be arranged in the particle beam (10; 10A; 10B; 10C) in the first operating mode, and cannot be arranged in the particle beam (10; 10A; 10B; 10C) in the second operating mode.

Description

Treatment station for particle bombardment of a patient and a particle therapy installation

The invention relates to a particle therapy installation for acceleration of at least two particle types, in which case a first particle type is accelerated in a first operating mode, and a second particle type is accelerated to in a second operating mode. The invention also relates to a treatment station having an apparatus for adaptation of a particle beam parameter of a particle beam of a particle therapy installation of this type.

EP 0 986 071 A3 discloses an ion beam therapy system which has two ion sources, an accelerator system with a linear accelerator, and a Synchrotron as well as an ion beam transport system. An ion beam therapy system such as this can be used to accelerate various ion types, and to pass them to treatment stations .

In addition to the provision of two separate ion sources in a corresponding manner to EP 0 986 071 A3, different ions can also be obtained with a configuration in which two ionization apparatuses, that is to say sources of different ion types, are interchanged and are operated alternately. In the following text, the expression particle source is used to mean both embodiment variants.

During a bombardment session in beam therapy, a patient is positioned at a treatment station, and the patient's positioning is verified with respect to the position on which the therapy plan is based. Bombardment then takes place from one or more incidence directions with particles, for example protons, pions, helium ions, carbon ions or oxygen ions. In the case of particle therapy installations such as those described in EP 0 986 071 A3, passive elements have until now been placed, generally manually, in a therapy beam path before the start of a bombardment session. For example, ripple filters or range shifters have thus been placed manually at the beam outlet, depending on the requirements.

A ripple filter is known, for example, from the publication by U. Weber and G. Kraft: "Design and construction of a ripple filter for a smoothed depth dose distribution in conformal particle therapy", Phys . Med. Biol. 44 (1999) 2765-2775.

Furthermore, a scattering system for a charged particle beam is known, for example, from US 5,440,133. The scattering system is in this case designed in such a manner that its thickness can be adjusted uniformly and continuously. For example, two wedges are moved into or out of the beam on opposite sides.

Various bombardment installations and techniques are described by H. Blattmann in "Beam delivery systems for charged particles", Radiat . Environ. Biophys . (1992) 31:219-231. This document describes, inter alia, the use of beamforming elements such as range modulators, collimators and bolus elements. A bolus is used, for example, for range matching of the rear dose distribution to a tumor. Passive elements can also be used for beamforming for particle therapy in conjunction with a raster scanning method.

One object of the invention is to simplify the procedure for operation of a particle therapy installation, in terms of the use of different particle types.

A further object of the invention is to simplify particle-specific adaptation of a particle beam parameter of a particle therapy beam. According to the invention, this object is achieved by a treatment station for particle bombardment of a patient as claimed in claim 1, and by a particle therapy installation as claimed in claim 5.

In this case, the treatment station and the particle therapy installation preferably have an apparatus for adaptation of at least one particle beam parameter of a particle beam of a particle accelerator installation, which can be operated at least in two operating modes, with a first particle type being accelerated in a first operating mode, and a second particle type being accelerated in a second operating mode, with the apparatus having a first beamforming element, which is held by a holding unit, with the beamforming element being adapted to the particle beam parameter and the holding unit being designed for positioning of the first beamforming element as a function of the operating mode such that particles pass through the first beamforming element in the first operating mode, and particles do not pass through the first beamforming element in the second operating mode.

One advantage of an apparatus according to the invention for adaptation of a particle beam parameter or its use in a particle accelerator installation is that there is no need for the manual positioning of a beamforming element, which is correspondingly time-consuming, and this can be carried out in an automated form with the aid of the holding unit and, in particular, an adjusting mechanism. This allows a patient to be bombarded with different particle types without having to manually replace a particle-specific beamforming element. This means that the particle beam can be adapted by means of a beamforming element, for example from a therapy control center for the particle therapy installation. This avoids the time- consuming interruption for replacement of beamforming elements. This simplifies the bombardment process and reduces the need for monitoring of the bombardment station with an operator being present.

When one embodiment of the invention is used in combination with raster scanning methods, this results, for example, in a number of particle-specific beamforming elements which are not patient-specific. The independence of the patient makes it possible to automate the adaptation of the particle therapy installation when changes take place between patients and/or particle types.

In one advantageous embodiment of an apparatus for adaptation of the beam parameter, this apparatus has an automatic drive unit for positioning of at least one beamforming element, with position sensors being provided in one particularly advantageous embodiment for monitoring the position of the beamforming element or elements.

In a further advantageous embodiment of the apparatus, this apparatus has a second beamforming element, which is held by the holding unit, influences the same and/or a different beam parameter, is also firmly connected to the first beamforming element or can be moved independently of the first beamforming element and in particular can be positioned in such a manner that particles pass through the second beamforming element in the second operating mode, and particles do not pass through the second beamforming element in the first operating mode. This makes it possible to operate the particle therapy installation automated on a particle-specific basis, since only the beam elements for the respective particle type are moved in an automated manner into the particle beam in the respective operating mode. This means that this embodiment has the advantage that, when two or more beamforming elements are used, the beam parameters of a plurality of particle types can be modified and adapted on a particle-specific basis. By way of example, possible beamforming elements in this case are ripple filters for widening of the particle energy distribution of the particle beam, a beam collimator for limiting the radial extent of the particle beam, a range shifter for adaptation of the particle energy, a bolus for range matching of the rear dose distribution to a tumor, and a scattering element for beam widening .

Further advantageous embodiments of the invention are characterized by the features of the dependent claims.

A plurality of exemplary embodiments of the invention will be explained in the following text with reference to Figures 1 to 6, in which:

Figure 1 shows a schematically illustrated particle therapy installation,

Figures 2 and 3 show a first embodiment of an apparatus for adaptation of a particle beam parameter,

Figures 4 and 5 show a second embodiment of an apparatus such as this, and

Figures 6 and 7 show a third embodiment of an apparatus such as this.

Figure 1 shows, schematically, a particle therapy installation 1 as is known, for example, from EP 0 986 071 A3. One embodiment of an apparatus 3 is used in this installation for adaptation of a beam parameter according to the invention.

The particle therapy installation 1 has two particle sources 5A and 5B as well as a vacuum beam-guidance and acceleration system 7 on the accelerator side 4. This also has, by way of example, a raster scanning apparatus 9. A configuration such as this is designed to accelerate different particle types from the particle sources 5A and 5B to energy levels of several hundred MeV, and to supply them to at least one beam therapy station 15.

During the bombardment process, a particle beam 10 is aimed at a patient 13 who is positioned on a couch 11. The beam therapy station 15 has a patient positioning apparatus (not shown) which allows the patient 13 to be positioned with the tissue to be bombarded at an isocenter 17 of the beam therapy station 15. The particle beam 10 preferably passes through the isocenter 17 with the raster scanning apparatus 9 at a null position.

For beam monitoring purposes, the particle therapy installation 1 also has a beam monitoring system 19 which, for example, monitors the beam position and the beam intensity. The beam monitoring system 19 is arranged between the patient 13 and the beam outlet of the vacuum beam-guidance and acceleration system 7. The apparatus 3 for adaptation of at least one particle beam parameter is preferably arranged downstream from the beam monitoring system 19 in the beam direction. This allows a particle beam parameter to be matched to the respectively currently used particle type, that is to say it provides beamforming elements for different particle types.

The apparatus 3 preferably has a compact design in order to occupy as little space as possible and to be easily accessible from the outside, for example for maintenance purposes.

The apparatus 3 allows beamforming elements to be positioned on a particle-specific basis as a function of the operating mode such that, for example, particles pass through a first beamforming element in the first operating mode and particles do not pass through the first beamforming element in the second operating mode, and such that particles do not pass through a second beamforming element in the first operating mode, and particles do pass through the second beamforming element in the second operating mode. For this purpose, the beamforming elements are positioned as required in the particle beam, for example in the scanning area in the path of the particle beam. Possible functional embodiments of the apparatus 3 will be explained in more detail in the following figures with reference to exemplary embodiments.

Figure 2 shows a sketch of an apparatus in which two beamforming elements 21, 23 can be moved on a plane independently of one another. The beamforming elements 21, 23 are held by a holding unit 25 which, for example, has a guidance system 27. The beamforming elements 21 and 23 are moved individually between a parked position and a beam position 29, with the aid of a drive apparatus 28 (see Figure 3) . The beamforming elements 21 and 23 are each located in their parked positions in Figure 2. The positions assumed are detected by sensors, for example by a sensor 30.

Furthermore, Figure 2 shows, schematically, a beam outlet 31 from the vacuum beam-guidance and acceleration unit, and a particle beam 1OA. The actual position of the beamforming element or elements 21, 23 is preferably monitored continuously (for example by an encoder) or discretely (for example by a limit switch, in this case the sensor 30), by means of at least one independent sensor.

Figure 3 shows a three-dimensional illustration of the apparatus from Figure 2 in an operating mode in which particles pass through one of the beamforming elements. In this case, by way of example, the beamforming element 21 has been moved to the beam position 29 by means of the drive apparatus 28. The drive apparatus has, for example, a belt system 32 which is driven by an electric motor. Figures 4 and 5 show a further embodiment, by means of which a beamforming element 33, for example a ripple filter, can be folded into and out of a horizontally running particle beam 1OB (to be more precise into one possible beam path) . The beamforming element 33 is mounted in a frame 35 for this purpose. In Figure 3, the beamforming element 33 is located in a horizontal parked position, from which it can be moved to a vertical beam position by means of a cam drive 37. The required drive is provided, for example, via an electric motor (which is not shown) by translation of the frame 35 in a lower guide rail 39. The shape of an upper guide rail 40 results in the frame 35 being folded from the lower horizontal parked position to the vertical beam position shown in Figure 5. The position change is reversible, and can be carried out quickly because of the short movement distance. This embodiment has the advantage that it requires space essentially only in the beam direction. Position monitoring is carried out, for example, once again by means of limit switches, which indicate the parked position and the beam position. An encoder can optionally be used to determine the position continuously.

A further embodiment is shown in Figures 6 and 7. In this case, a frame structure 41 is used, which has space for at least one passive beamforming element 42 and possibly also an empty position (without a beamforming element) . One beamforming element is preferably provided for each particle type, and the beamforming elements are separated from one another by a fixed distance in the frame 41. Beamforming elements (or else no beamforming element) are positioned on a particle-specific basis in the particle beam by movement of the frame structure 41 along a guide 43. In one advantageous embodiment, frame areas which are located outside the guide 43 can be folded away at the side. In this case as well, the frame structure can be driven, for example, by an electric motor. The position change of the beamforming elements is reversible, automated and can be carried out quickly. The position of the frame structure 41 can likewise be determined continuously or discretely.

For all the possible embodiments, it can be said that the automation of the position changing and replacement process and the use of beamforming elements which are designed for different particle types makes it possible to adjust a particle therapy installation for different bombardment modes with different particle types in a short time. This avoids the time-consuming manual intervention of an operator, reduces the time for which a patient has to stay in the beam therapy station, and increases the patient throughput. Furthermore, the patient bombardment can be optimized on a particle-specific basis with respect to the procedure, and incorrect beamforming element fits can be avoided by the automatic driving and monitoring of the apparatus.

Claims

Patent Claims

1. A treatment station (15) for particle bombardment of a patient, having an apparatus (3) for adaptation of at least one particle beam parameter of a particle beam (10; 1OA; 1OB; 10C) of a particle therapy installation (1) , with the treatment station being designed for operation in at least two operating modes, with the treatment station being operable in a first operating mode with a first particle type and in a second operating mode with a second particle type, with the apparatus having at least one first beamforming element (21; 23; 33; 42), which is held by a holding unit (25; 35; 41), with the beamforming element (21; 23; 33; 42) being designed for adaptation of the particle beam parameter and the holding unit (25; 35; 41) being designed for positioning of the first beamforming element (21; 23; 33; 42) as a function of the operating mode, in such a manner that the first beamforming element (21; 23; 33; 42) can be arranged in the particle beam (10; 1OA; 1OB; 10C) in the first operating mode, and cannot be arranged in the particle beam (10; 1OA; 1OB; 10C) in the second operating mode.

2. The treatment station (15) as claimed in claim 1, with an automatic drive unit (28) being provided for positioning of at least one of the beamforming elements (21; 23; 33; 42) which, in particular, has position sensors (30) for monitoring the position of the beamforming element (21; 23; 33; 42) .

3. The treatment station (15) as claimed in claim 1 or 2, with a second beamforming element (21; 23; 33; 42) being provided, which is held by the holding unit (25; 35; 41) , is designed to influence the same and/or a different beam parameter, is firmly connected to the first beamforming element

(21; 23; 33; 42), can be moved independently of the first beamforming element (21; 23; 33; 42) and in particular can be positioned in such a manner that the second beamforming element (21; 23; 33; 42) can be arranged in the particle beam (10; 1OA; 1OB; 10C) in the second operating mode, and cannot be arranged in the particle beam (10; 1OA; 1OB; 10C) in the first operating mode .

4. The treatment station (15) as claimed in one of claims 1 to 3, with one of the beamforming elements (21; 23; 33; 42) being a ripple filter for widening of the particle energy distribution of the particle beam, a beam collimator, a range shifter, a bolus or a scattering element.

5. A particle therapy installation (1) for acceleration of at least two particle types and with a treatment station (15) as claimed in claim 1 for bombardment of a patient, in which case a first particle type for particle therapy can be supplied to the treatment station (15) in the first operating mode, and a second particle type for particle therapy can be supplied to the treatment station (15) in the second operating mode.

6. The particle therapy installation (1) as claimed in claim 5, with the apparatus (3) for adaptation of the beam parameter having an automatic drive unit (28) for positioning of at least one of the beamforming elements (21; 23; 33; 42), which, in particular, has a position sensor (30) for monitoring the position of the beamforming element (21; 23; 33; 42) .

7. The particle therapy installation (1) as claimed in one of claims 5 or 6, with a first and a second particle source (5A, 5B) being provided for production of the different particle types, and a vacuum beam-guidance and acceleration system (7) being provided for particle acceleration, with the apparatus (3) for adaptation of the beam parameter being arranged in the particle beam profile close to the patient, in particular after the emergence of the particle beam (10; 1OA; 1OB; 10C) from the vacuum beam-guidance and acceleration system (7) .

8. The particle therapy installation (1) as claimed in one of claims 5 to 7, with a second beamforming element (21; 23; 33; 42) being provided, which is held by the holding unit (25; 35; 41) , is designed to influence the same and/or a different beam parameter, is firmly connected to the first beamforming element

(21; 23; 33; 42) or can be moved independently of the first beamforming element (21; 23; 33; 42) and in particular can be positioned in such a manner that particles can pass through the second beamforming element (21; 23; 33; 42) in the second operating mode, but particles cannot pass through it in the first operating mode.

9. The particle therapy installation (1) as claimed in one of claims 5 to 8, with one of the beamforming elements (21; 23; 33; 42) being a ripple filter for widening of the particle energy distribution of the particle beam (10; 1OA; 1OB; 10C), a beam collimator, a range shifter, a bolus or a scattering element .