DEVICE FOR CONCENTRATING IONISING RADIATION FLUENCE, WHICH FOCUSES ELECTRONS AND X-RAY PHOTONS AND IS ADAPTABLE

Abstract

A device for concentrating ionizing radiation fluence is disclosed having a coupling structure linking the external radiotherapy device with linear accelerator to an external structure, whose central axis is hollow with an input window through which electrons enter attaching to the rotation device; a rotation system linking the coupling structure with a coupling flange rotating an inner structure; a deflection system in the inner structure, wherein the deflection system has first and second magnetic deflection devices; a system for controlling the focal point, which is in the electron deflection system, having an electronic control system controlling a set of motors that produce coordinated movements of the second magnetic deflection device, a correction element and a collimator, which change the position of the focal point; and at least two laser diodes on the edge of the collimator (25) pointing towards the focal point determining the position of the electron beam generated.

Claims

1.-52. (canceled)

53. An ionizing radiation fluence concentrator device of variable focus adaptative to a high-energy electron source of an external radiotherapy device with linear accelerator, to focus and guide the focus continuously and less invasively, within a given area, wherein said device comprises: a coupling structure that joins the linear accelerator external radiotherapy device with an outer structure, whose central axis is hollow with an electron window and anchoring means for attaching to the rotation device by clamping means; a rotation system that is joint to the coupling structure with a coupling wire rotates the structure; an electron deflection system that is in the interior structure, wherein the deflection system comprises, a first and a second magnetic deflection device; a focus control system, which is in the electron deflection system, comprising an electronic control compartment that controls a set of motors that generate coordinated displacements of the second magnetic deflection device, a collimator in a collimation unit, which allows to change position of the focal point; and at least two laser lights located at the edge of the collimator pointing towards the focus allowing to determine the generated electron beam position.

54. The device according to claim 53, wherein the rotation device comprises; a geared motor that is fixed to the coupling structure by bolts wherein the coupling structure is a tray.

55. The device according to claim 53, wherein the magnetic electron deflection system is formed by a first magnetic deflection device that deflects the electron beam between 60° and 100° with respect to the direction of the incident electron beam and a second magnetic deflection device, of reverse polarity to the first magnetic deflection device, deflects the electrons towards a focal point located on the optical axis, which comprise magnets that have a joint intensity between 0.3 T and 1.2 T, wherein, the entire magnetic deflection system is fixed to a support structure.

56. The device according to claim 53, other version comprises electron beam correction elements wherein: to the output of each magnetic deflection device is positioned a trajectory aligning magnetic quadrupole of the trajectory electron beam and/or dipole that aligns the electron beam.

57. The device according to claim 56, wherein at the output of the first magnetic deflection device and/or in front of the first quadrupole at least one magnetic dipole is positioned that focuses the trajectory of the electron beam and at the output of the second magnetic deflection device a magnetic dipole is positioned that focuses the trajectory of the electron beam.

58. The device according to claim 55, wherein the deflection system lies in a vacuum outer housing, which is adapted to the configuration of the magnets, wherein, the first magnetic deflection device is joint to the box inlet wall in a direction perpendicular to the incident electron beam and the second magnetic deflection device is inclined to more than 0°, clockwise, with respect to the first deflection device.

59. The device according to claim 55, wherein the magnetic deflection devices are inclined so that the electron beam emerges from the first magnetic deflection device and deflects at an angle close to 90°.

60. The device according to claim 55, wherein the magnetic deflection devices are constructed with permanent magnets or with electromagnets.

61. The device according to claim 53, wherein each magnetic deflection device is formed of two magnets, wherein each magnet has a magnetic field intensity between 0.2 T and 0.7 T located facing its opposite poles on its polar faces, a non-magnetic lateral support, with an elongated hole in the central area, allow positioning the magnets thanks to protrusions that prevent them from joining; C-shaped field closing element, located on the sides of the magnets, close the magnetic circuit.

62. The device according to claim 53, wherein each of the magnetic deflection devices has a non-magnetic part with a non-magnetic support with central stand so that when the electron beam enters laterally through the area of the central hole of at least one of the magnetic deflection devices the beam exits through the same face through which it entered.

63. The device according to claim 53, wherein it uses quadrupole manufactured with permanent magnets and magnetic dipoles are based on permanent magnets.

64. The device according to claim 55, wherein the shape of the pair of permanent magnets that make up the magnetic deflection devices are of curved and irregular cuts on one of their faces.

65. The device according to claim 61, wherein the magnetic deflection devices have at least one curved cut field closing element of the magnet.

66. The device according to claim 53, wherein the focus control system comprises magnetic deflection devices that are fixed in solidarity to a support structure.

67. The device according to claim 53, wherein the focus control system comprises a first stepper motor that moves the second magnetic deflection device along a rail of the second magnet linearly displacing the second magnetic deflection device with respect to the rotational axis along the line of the trajectory of the electron beam, wherein the second magnetic deflection device is joined in solidarity with the collimator wherein the focus control system comprises a second magnetic deflection device rotates by driving a second motor of the angular head and the collimator rotates angularly synchronously by means of another angle of the collimator and linearly displaced by means of a collimator linear motor and a collimator rail.

68. The device according to claim 53, wherein the focus control system comprises a first stepper motor that moves the second magnetic deflection device along a rail displacing it with respect to the rotational axis along the line of the trajectory of the electron beam, wherein the second magnetic deflection device rotates, by driving an angular motor and the collimator is angularly displaced by means of an angular motor of the collimator and linearly displaced by means of a linear motor and in the collimator rail.

69. The device according to claim 53, wherein the collimation unit comprises: collimator and shielding with an attenuation material with a Z greater than 70, which radially envelops the metallic septa tube with low atomic number (Al); a. a heat dissipation housing, which envelops the collimator, for thermal dissipation; b. a white filter disc movable, inserted within said collimator in a side compartment to allow free passage of the electrons, wherein the white filter disc is displaced to the septa to generate X photons; and c. a head shielding which completely covers the second magnetic deflection device, which prevents radiation leakage of X photons.

70. The device according to claim 69, wherein the collimator further comprises: a white filter disc exchange system, having: displacement means that translate the white filter disc to one of two positions, which are in the side compartment to allow free passage of the electrons or in the central conical hole to generate X photons, wherein the heat sink is manufactured of materials with thermal conductivity such as aluminum, copper, boron, tin or titanium or bronze or alloy thereof and the heat sink further comprises concentric conductive cylinders that transmit heat homogeneously, outwardly or ventilation rings for dissipating heat outwardly.

71. The device according to claim 69, wherein the white filter disc is manufactured of tungsten or lead or silver or gold or tin, or alloys thereof.

72. The device according to claim 53, further comprises an electronics and counterweight support system, comprising a counterweight support, a counterweight stepper motor, a counterweight, wireless communication means, a wireless communication compartment with an electronic control compartment of the stepper motors, and battery compartment that power all devices being in rotation.

73. The device according to claim 53, wherein the electron deflection system is in an open environment.

74. The device according to claim 53, wherein a first operation control controls the operation of the linear electron accelerator (LINAC) to enable the operation plan, a second control to control the rotation speed and stepper motors that allow the variation of the position of the focus and of the device that cuts the electron beam; and wherein, a monitoring system of the emerging radiation beam, which is located at the bottom of the collimator comprising two gas ionization chambers with thin conductive windows (0.1 to 1 mm).

75. The device according to claim 53, wherein collimator comprises at its distal end an electron beam extender tube, which minimizes the dispersion of said electrons in the air.

76. The device according to claim 53, wherein at least two laser guides pointing towards the focus are attached to the bottom of an external structure joined by a straight bar.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Before describing each of the drawings, the numerical list of each of the elements described in the figures is included.

[0037] FIG. 1. Summarized view of the invention.

[0038] FIG. 2. General scheme of the invention viewed in perspective.

[0039] FIG. 3. LINAC coupling means in a commercial alternative.

[0040] FIG. 4. LINAC coupling means, in another commercial alternative.

[0041] FIG. 5. Rotation device in general cutaway view.

[0042] FIG. 6. Rotation device with two perspective views.

[0043] FIG. 7. Main deflection system, and electron guide, with perspective views A and side view B.

[0044] FIG. 8. Structure of the main deflection system, and electron guide, with perspective views A and side views B.

[0045] FIG. 9. Deflection system with the second magnetic deflector embedded within the head.

[0046] FIG. 10. Deflection system without guide tube with sealed unit.

[0047] FIG. 11. Deflection system with guide, fixed (58) A, telescopic (59) B, telescopic tubes and flexible and telescopic tube S (60) C.

[0048] FIG. 12. A thin cylindrical white disk with electron filter (19) inserted into the collimator tube (25) in perspective views (A), wherein the double arrow shows the displacement of the thin cylindrical white disk with electron filter, to leave the device in electron mode, when the thin cylindrical white disk with electron filter (19) is in the side compartment (90) or to leave the device in photon mode X, when the thin cylindrical white disk with electron filter (19) is in the septa of the collimator or when the electron beam impacts the thin cylindrical white disk with electron filter (19) and detail (B) of the thin cylindrical white disk with electron filter (19).

[0049] FIG. 13. Collimator with heat sink with built-in filter white (19) with concentric conductive cylinders (82), septa tube (83), septa (84), attenuation material (85) plus heat sink rings (86), preferably manufactured of materials with thermal conductivity such as aluminum, copper, boron, among others, in perspective views (A) and in axial section (B).

[0050] FIG. 14. Conical heat sink (87), in perspective views (A) and axial cut (B).

[0051] FIG. 15. Detail of moving target area with cut views of FIG. 1 (A) and zoom (B).

[0052] FIG. 16. Detail of a fixed target in collimator tunnel A and at the exit of head B with conical collimator.

[0053] FIG. 17. Head shielding with perspective views (A) and axial cut (B).

[0054] FIG. 18. Device with electron version focus control with fixed focus, with perspective views (A) and side views (B).

[0055] FIG. 19. Device with electron or X-ray photon version focus control with fixed focus, with perspective views (A) and side (B).

[0056] FIG. 20. Device with focus control electron version, with focus modification through radial displacement for radius modification, with perspective views (A) and side views (B).

[0057] FIG. 21. Device with electron version or X-ray photon focus control, with focus modification through radial displacement for radius modification, with perspective views (A) and side views (B).

[0058] FIG. 22. Device with electron version focus control, with focus modification through convergence angle variation, with perspective views (A) and side views (B).

[0059] FIG. 23. Device with electron or X-ray photon version focus control, with focus modification through convergence angle variation, with perspective views (A) and side views (B).

[0060] FIG. 24. Device with electron version focus control, with focus modification through convergence angle variation and with focus modification through radial displacement, with perspective views (A) and side views (B).

[0061] FIG. 25. Device with electron or X-ray photon version focus control, with focus modification through convergence angle variation and with focus modification through radial displacement, with perspective views (A) and side views (B).

[0062] FIG. 26. Connection to external energy by ring and brushes.

[0063] FIG. 27. Support for counterweight with compartments for control electronics of device motors, wireless communication device and battery.

[0064] FIG. 28. Scheme of the communication and control system.

[0065] FIG. 29. Diagram of electron beam interruption device.

[0066] FIG. 30. Permanent magnet with oblique incidence (A: isometric view, B: front view, C: rear view and D: view of an isometric cut).

[0067] FIG. 31. One-piece permanent magnet holder or mono-block.

[0068] FIG. 32. Magnetic quadrupole detail of permanent magnets.

[0069] FIG. 33. Detail of a permanent magnet focusing circular magnetic dipole.

[0070] FIG. 34. Scheme of the basic deflection system with correction elements.

[0071] FIG. 35. Cut-faced magnet, as correction elements.

[0072] FIG. 36. Deflection diagram with magnets if deflection elements, with cuts (A), both inclined with entry and exit on the same faces (B) and equal to previous with cut for focus (C).

[0073] FIG. 37. Scheme of 2D scanning de focus for out-of-axis dose painting.

[0074] FIG. 38. Electron output device with extender element (79), which minimizes the dispersion of electrons in the air.

[0075] FIG. 39. Device, with fixed electron output; with fixed output (A) and with lateral displacement and varying angle (B)

[0076] FIG. 40. Dual device (electrons or X-ray photons) with fixed output (A) and with lateral displacement and varying angle (B)

[0077] FIG. 41. Radiation monitoring ionization cameras.

[0078] FIG. 42. Laser guides for calibration and visualization of the rotating beam.

[0079] FIG. 43. Converging irradiation scheme of rotating beams with fixed radius (A).

DETAILED DESCRIPTION OF INVENTION

[0080] Converging irradiation scheme of rotating beams with varying rotation radius (B).

[0081] As shown in FIGS. 1 and 2, the device is formed of the following main parts: [0082] A. Electron coupling and input means. [0083] B. Rotation device. [0084] C. Electron deflection system. [0085] D. White disc and mobile filter (19). [0086] E. For electron passage and/or X-ray photon generation. [0087] F. Dissipation and shielding collimation system. [0088] G. Focus control and sweep system. [0089] H. Dosimetric system and laser guides. [0090] I. Device control system.

[0091] The invention consists in the following: a coupling means (A) by which the electrons of the accelerator enter, this coupling means is basically a tray (1) that adjusts in shape and means to which each brand or models of accelerator currently use, it also has cavities and a central hole with window (6). It is followed by a rotation device (B) whose central axis (5) is hollow and is fixed to the coupling means by fixing means (4) such as bolts, so that the electrons can enter, the motor (8) and the pulleys (9) are fixed in the cavities of the coupling means. Further down is the deflection system (C) which consists in a rotating structure (17), thanks to the previous rotation device; this system that deflects and aligns the electron beam is formed by two magnetic deflectors with high intensity permanents close to 1 T, the first (13) opens the electron beam and the second closes it (14). The electrons emerging from the second focal direction deflector, as shown in FIG. 1 and FIG. 2. Depending on the choice, the electrons may or may not impact a mobile thin metal disk (19a) of high atomic number, greater than 50, inserted into a metal cylindrical heat sink and electron filter (19b) for thermal dissipation (D); the impact of the electrons generates X-rays, mainly in the focal direction of the system. A collimation and shielding system (20) (E) allows electrons or X-rays generated in the white disk to be collimated in the direction of the focus and the remainder to be absorbed by the shielding. So that there will be a narrow net electrons or X-ray photon beam (beamlet) emerging from the collimator output (25) in rotation, with varying rotation radius and always pointing towards a focal point similar to that achieved with an converging X-ray photon beam, but in this case it is a single beamlet in a dynamic mode. The position of the focal point can be modified thanks to a focus control and sweep system (F), this is modified thanks to the movement of the second magnet in conjunction with the coordinated movement of the collimator; the emerging beam dosimetry of the collimator is measured by a set of ionization chambers and also has one or more laser light sources pointing to the focus (G). Finally, a software controls all parameters and operating modes of the apparatus (H). Detail of each of these parts is described below.

A. Electron Coupling and Input Means

[0092] The electron coupling and input means is formed by a metal plate (1) of similar characteristics to the coupling means that each device already has according to its brand, as shown in FIG. 3 the coupling and input system adjusted to a type of commercial device and in FIG. 4 the one used by another brand and in general this coupling means is the same, so it can be adapted with minor modifications in size and shape according to the brand used. It also has cavities (a, b) and a central hole and holes with threads to be anchored to the rotation device by means of bolts.

B. Rotation Device

[0093] The main version of the rotation device is attached by clamping means (4), such as bolts, to the electron coupling and input means (A) consists in a set of pieces formed by: a central axis (5) is hollow that allows the rotation of the system, input window (6), and the electron passages, with bearings (3) to facilitate and fix rotation, with a support to the central axis (2) that allows the bearings to be contained, with a gear (7) that is part of the central axis, a coupling flange (8) that allows fixing to the deflection system (503), a gear belt (9) that connects to the geared motor (10) through a pulley with gears (11), which is tensioned by another pulley (40) with axle that can be slid by the rail (41) into a groove that is fixed by a screw (42). This whole assembly allows rotational movement of the electron beam, which is described below. FIG. 5 and FIG. 6.

[0094] Another preferred configuration of the rotation device described above is built entirely with gears which connect directly to the geared motor with the central gear, its simplicity is obvious and no drawing of this version is presented.

[0095] Another preferred configuration of the rotation device described above is based on the fact that it goes above the coupling device (A), however, this option implies that the output window of the LINAC must be removed, or this one replaced with another that can be retracted in the concentration mode this option. It involves a greater intervention, however, there is a better use of the available space, gaining about 8 cm of space between the output and the isocenter.

[0096] Another preferred configuration of the rotation device described above is based on an adaptation of the head rotation system of LINAC itself. Like the previous case, the rotation system is above the coupling device (A) and the deflection system is practically glued to the latter. However, the output window of the LINAC must be removed or this replaced with another that can be retracted in the concentration mode.

C. Electron Deflection System

[0097] The main version consists in two permanent deflector magnets and two permanent magnetic quadrupole and/or focusing dipoles, the first of which is a fixed deflector magnet that opens the beam (13) and goes in an oblique position to the direction of the incident electron beam at the output thereof there is a quadrupole magnetic device (15) that aligns the output beam, also built with permanent magnets. A second magnet (14) similar to the first deflects the beam in the opposite direction, bending it towards the axis, the incidence of the electrons in this second magnet is oblique and it occupies the shortest possible distance in the incidence direction. The electrons are driven through a tube of non-magnetic S-shaped material (16) into vacuum passing through the different devices, entering through the first deflector magnet up to outputting through the quadrupole (18) to the output of the second deflector magnet. See FIG. 7. The structure on which the deflection system is mounted has a clamping ring with holes (43) that is attached to the coupling flange (8) of the rotation system is shown in FIG. 8.

[0098] When a filiform beam of quasi-monochromatic electrons passes through a magnetic deflection element, it undergoes an expansion of the filiform beam, due to the different radii of curvature experienced by the electrons generated by their energy differences between the electrons of the beam, since this is not 100% monochromatic. A schematic of a deflection base configuration with the two deflectors with the permanent magnets and the beam correction elements is shown in FIG. 34. This beam correction can also be performed by cutting on one or more faces of the base magnets, as shown in FIG. 35 and FIG. 36 A. A schematic configuration without the electron beam correction elements with and without cutting magnets is shown in FIGS. 36 B and 36 C.

[0099] Another preferred configuration of the deflection system described above is with sealed outer housing (34) with the two magnets inclined, with the first magnet at 45° inclination for 90° output of this magnet, in a sealed environment as shown in FIG. 9.

[0100] Another preferred configuration of the deflection system described above is with the outer housing with the two magnets inclined and shielding head adhered to this deflection system with the second magnetic deflector embedded within the head FIG. 10

[0101] Another preferred configuration of the deflection system described above, has a fixed S-shaped guide tube FIG. 11 A.

[0102] Another preferred configuration of the deflection system described above, has an extendable S-shaped guide tube FIG. 11 B.

[0103] Another preferred configuration of the deflection system described above, has an extendable and flexible S-shaped guide tube FIG. 11 C.

D. Mobile Disc and Filter for Electron Passage and/or X-Ray Photon Generation

[0104] This system consists in a thin disc (26) of a thermal conductive material, light thermal conductive materials Cu or Al, FIGS. 12 A and B which goes inside the collimation tube FIG. 13 A, which is manufactured of several concentric cylinders of different conductive metals (84) and photon attenuators X (87), with a system of circular thermal conductive vanes (82) adhered to the outside of the collimator FIG. 13 B and in turn it is attached by means of a coupling (83) to the structure of the shielded head of the rotating deflection system at the output of the electron beam of the second collimator FIG. 10. This disc is the white filter (19) where, the electrons impact and there X-rays are generated by the predominantly Bremsstrahlung effect. An appropriate combination of the thickness of the target material, its high atomic number and the energy of the electrons will allow the generation of X-ray photons mainly in the direction of incidence and the removal of the disk will allow output of electrons

[0105] FIG. 12 A shows the inner part of the collimates and a zoom (B) showing a detail of how the whole of the invention is going in the part where the X-rays are generated, the electrons are filtered, shielded and collimated.

E. Dissipation and Shielding Collimation System

[0106] The impact of the electrons on the target generates heat, although they must travel a greater distance and pass through the deflectors that expand the beam and degrade it energetically in most X-ray equipment including LINAC, the heat generated in a small area of the order of ten square millimeters in the impact zone, which it is necessary to extract from there by means of a water cooling system. In this case because the target is a ring inserted into a thin disc of a conductive material, of high atomic number greater than 50 (VV) all this thermal energy is conducted and distributed in a much larger area through the heat exchanger rings, water cooling is not necessary and therefore the heat can be extracted by circulating air, due to the movement of the device thanks to the rotating system.

[0107] This collimation and shielding system (F) is formed by a cylindrical collimator (25) similar to that used in stereotactic radiosurgery adjusted to lower operating energy of the LINAC (6 MeV), since for higher energy it is required a greater size. That is, the dose concentration mode is recommended for the lower operating energies of the LINAC. In this way less powerful magnets are required to perform beam deflection and less shielding, all this translates into cost and space. The collimator has an internal channel or septa (85) (54) FIG. 13.

[0108] Another preferred option of the collimation system is by means of a collimator cooling system with conical vanes (88). FIG. 14.

[0109] Another preferred option features a mobile electron white filter 19 allowing selection of the output of the radiation type, electrons without the filter in the septa channel (85), or X-ray photons with the white filter. The shift mechanism consists in a piece containing the filter blank (94) within a small cavity (95) of about 1 cm.sup.3 by the side of the septa, the piece of the filter blank is attached to a spring 96 at the proximal end which in turn the spring is attached to a string (97) at its other distal, which can be moved along a curved hole (98), and is fixed at its end by a lock (99). FIG. 15.

[0110] Another preferred configuration of the white filter disk is that it is located inside the septa FIG. 16 A.

[0111] Another preferred configuration of white filter disk is that it is located in the shielding head output of the second magnetic deflector and uses conical shielding collimator FIG. 16 B

[0112] Another preferred configuration for electron and photon X output requires shielding (20) as shown in FIG. 17, which has a conical rectangular input channel (89), an input coupling means (90), an input coupling seal (91), an outer housing (92), an output tube (92), an output channel (93) and a coupling means for the collimator (94).

F. Sweep and Irradiation Focus Control System

[0113] This system allows to vary the position of the concentration point of the X-radiation or focus, although by default this focus is located in the isocenter of the LINAC. The movement of the focus around the isocenter allows for a dose scan within the tumor, better known as a “dose painting” technique that is not used in this type of accelerator, but thanks to this invention it is possible to carry out.

Focus Control

[0114] A preferred configuration without focus control, for electrons in this option the parts are fixed without displacements or rotations, is the simplest version of the invention, as shown in FIG. 17. Control or sweep by the focus is performed by movements of the object to be irradiated, for example, moving a stretcher with the patient to be treated.

[0115] In another preferred configuration without focus control, for electrons or X-ray photons, in this option the parts are fixed without displacements or rotations, it is the simplest version of the invention, as shown in FIG. 18. Control or sweep by the focus is performed by movements of the object to be irradiated, for example, moving a stretcher with the patient to be treated.

[0116] Another preferred configuration is of focus control with electron convergence fixed angle, in this configuration it is possible to achieve displacement of the focus by linearly displacing (moving away or approaching) the magnet 2 (14) with respect to the axis of rotation, the displacement is carried out by driving a motor (11), wherein the displacement is along the electron trajectory line that is set after passing the magnet 1 (13). This movement is made with deflector 2 (14) in solidarity with collimator 25, as shown in FIG. 19.

[0117] Another preferred configuration is of focus control with electron convergence angle X, which corresponds to a dual configuration, in this configuration it is possible to achieve displacement of the focus by linearly displacing (moving away or approaching) the magnet 2 (14) with respect to the axis of rotation, the displacement is carried out by driving a motor (12), wherein the displacement is along the line of the trajectory of the electrons that is established after passing the magnet 1 (13). This movement is made with deflector 2 (14) in solidarity with collimator (25), as shown in FIG. 20.

[0118] Another preferred configuration is focus modification with fixed incidence angle, it is the same to the above plus beam correction elements, quadrupoles and dipoles, not shown in the figures.

[0119] Another preferred configuration is focus modification with displacement and varying angle: with electron output, in this configuration it is possible to achieve displacement of the focus by angularly displacing the magnet 2 (14) with respect to the axis of rotation, the displacement is carried out by driving three stepper motors, wherein the magnet 2 (14) is displaced by driving the first angular motor (22), the angular displacement of the collimator (25) by means of the second angular motor (22a) and with a linear movement, through the linear motor (22L), as shown in FIG. 21.

[0120] Another preferred configuration is focus modification with displacement and varying angle and linear displacement of the focus, wherein this configuration is possible to achieve displacement of the focus by linearly displacing (moving away or approaching) the magnet 2 (14) with respect to the axis of rotation, the displacement is carried out by driving a motor (12), wherein the displacement is along the line of the trajectory of the electrons that is established after passing the magnet 1 (13), together with the displacement of the focus by angularly displacing the magnet 2 (14) with respect to the axis of rotation, the displacement is carried out by driving three stepper motors, wherein the magnet 2 (14) is displaced by the drive of the first angular motor (22), the angular displacement of the collimator (25) by means of the second angular motor (22a) and with a linear movement, through the linear motor (12), as shown in FIG. 21.

[0121] This movement is made with deflector 2 (14) in solidarity with collimator (25), as shown in FIG. 20.

[0122] Another preferred configuration is focus modification with displacement and varying angle: with dual output, electrons or X-ray photons. This option adds to the above the ability to rotate magnet 2 with a motor (53) and collimator (25), in addition to the displacement. This option is the most complete and in turn most complex and uses at least four stepper motors, as shown in FIG. 22.

[0123] Another preferred configuration is focus modification with displacement and varying angle: it is the same to the above plus beam correction elements, quadrupoles and dipoles.

Sweep

[0124] Another preferred configuration for achieving a 2D sweep of the focus is achieved by a combined movement between rotation and exit angle of the rotating beam in each rotation FIG. 37. Which is controlled by the scanning software that sets angle parameters of the magnetic deflector 2 plus collimator in electron version of the head of the magnetic deflector 2 plus collimator in dual version, that is, for each rotation and part of rotation or exposure time associated with a scanning point, in a discrete or continuous scanning mode, in other words rotating and sweep at the same time, with a out-of-axis scanning focus moving (painting) in the X,Y plane, as shown in FIG. 37.

[0125] Another preferred configuration for performing a 3D scan of the area of interest contemplates the application of the rotating beam, either electron or X-ray photon, with out-of-axis focus as shown in FIG. 33. This embodiment is achieved through the controlled angular movement of the second baffle and collimator.

[0126] Another preferred configuration of focused irradiation is by rotation with varying radius, helical movements of the rotating beam in this way a major input area of the radiation is achieved and greater concentration in the focus FIG. 20.

G. Dosimetric System and Laser Guides

[0127] The dosimetric monitoring system consists in two gas ionization chambers with thin aluminized windows, these go to the output of the collimator, which as conventional equipment, allow to monitor the radiation intensity delivered by the device see FIG. 37 in addition to this there are two or more laser guides pointing towards the focus. (FIG. 38).

H. Device Control System

[0128] As previously mentioned, the system as a whole is controlled by software that establishes the operating conditions in conjunction with the operation of the LINAC coordinate the different modes of operation according to the treatment plan that is established. The angular speed of rotation is controllable by stepper motors, electron braking, focus position and rotation cone angle.

[0129] Another preferred configuration is wireless is via Bluetooth, the latter option is simpler from a mechanical point of view, since it introduces an electronic communication element without physical connectors compared to the previous option. In this option, it may be used batteries that can be housed in a compartment (31) located on the arm (30) of the rotation device supporting counterweight (34) FIG. 27.

[0130] In one version, the energy to power the motors found in the rotating unit may be directly delivered by an external source through a rotary connector 58, which may be “brushes” FIG. 26 that connect to two conductive rings 59 that are concentric and surround the coupling means A.

[0131] Control scheme: Once the device is installed in the LINAC head, an external general operating mode control software changes the operating mode allowing the electron dispersing sheet to be removed, so that the electron beam passes freely through the air, which will generate a slight braking of the order of 2% to 5% and electron dispersion that reduces the fluence by 8% to 10%, for a 6 MeV LINAC, in a standard model of a manufacturer. This slight reduction is not significant with respect to the beam at the output of the reduction waveguide of the dispersing sheet FIG. 24.

[0132] Another preferred configuration of the device has an electron braking unit (61), which allows to add rapid cuts of radiation in certain angular positions that follows the first quadrupole which is quick-activating. It has metal sheets, one or more, (62) that close and open magnetically or with one or more quick-acting stepper motors (63) FIG. 25.

[0133] One of the most important elements of the technological challenge that allows the success of this invention in its best version and that is ultimately allows it to be coupled to a LINAC in an operating mode, is the deflection capacity of electrons that travel around 96% of the speed of light in the vacuum, in a longitudinal distance of two centimeters. Different types of magnets can generally be used, either electromagnets or permanent magnets. Permanent high-intensity and parallepiped-shaped magnets of reduced dimensions of 2.5×2.0×5.0 cm (the shape and dimensions of the magnets are only by reference and can be different) with a field in surface of 0.6 Tesla were used, however, for a spacing of 10 mm and a length of 2 cm a field close to 1 T is required to have a deflection at the output of the magnets close to 90°. This requirement is impossible to achieve in traditional configurations using iron and between iron as field area. The key is to place the magnets face to face with the opposite poles and make use of the principle of overlapping fields, however, this is very difficult to achieve given the great attraction force close to 200 kg, which is generated when the magnets are only 10 or 8 mm away from each other, to achieve this non-magnetic support pieces (65) were used as shown in FIG. 26 with oblique incidence requires another non-magnetic support (67).

[0134] Additionally, other devices for assembling magnets or using magnets are shown, a mono-block permanent magnet holder for placing the permanent magnets of the magnetic deflectors is shown in FIG. 27. FIG. 28 shows the detail of permanent magnet focusing magnetic quadrupole used in this proposal and FIG. 29 shows the detail of a permanent magnet focusing circular magnetic dipole.

[0135] Weight and Dimensions: The weight and dimensions of the dimensions of the device are determined by the size and energy of the external radiotherapy equipment to which it could be adapted as the operating energy, typically 6 MeV is a very common energy used in the different types of known accelerators, but it is also possible to work with energy less than 4 MeV, this allows reducing the weight compared to a device working at 6 MeV. For a 6 MeV device, a weight of about 50 kg has been estimated and for a 4 MeV device, this weight could be reduced by about 40 kg, due to the lower amount of material intended to shielding. The outer diameter of the device ranges from 85 to about 30 cm in diameter and approximately 20 cm in length, depending on the outer diameter of the LINAC head of the company being considered. All these dimensions include the shielding that must be used in the target area and its weight only varies depending on the energy according to what is indicated above. Another element that also adds weight to the device is the collimator, the size of this unit is dependent on the energy to be used and its length varies between 4 and 6 cm for 4 and 6 MeV, respectively.

[0136] The size and weight can be further reduced if the operating energy of the LINAC can be reduced below 4 MeV and the principle of operation and forms of control of the rotating beam remains the same as described in the previous cases, for all the options described.

DETAILED DESCRIPTION OF PARTS AND VARIANTS

[0137] This invention consists of an ionizing radiation fluence concentrator device (500) of varying focus adaptable to a high-energy electron source of an external radiotherapy device with linear accelerator, to focus and guide the focus continuously and less invasively, within a given area, comprising:

[0138] a coupling structure that joins the linear accelerator external radiotherapy device with an outer structure (101), whose central axis (5) is hollow with an input window (6) by which electrons and anchoring means for attaching to the rotation device by clamping means (4);

[0139] a rotation system that is joint to the coupling structure with a coupling flange (8) rotates an inner structure (102);

[0140] an electron deflection system (503) that is in the interior structure (102), wherein the deflection system (503) comprises, a first and a second magnetic deflection device (13, 14);

[0141] a focus control system, which is in the electron deflection system (503), comprising an electronic control system (31) that controls a set of motors (12, 22) that generate coordinated displacements of the second magnetic deflection device (14), a correction element and a collimator (25), which allows to change position of the focal point; and

[0142] at least two laser diodes (74) located at the edge of the collimator (25) pointing towards the focus allowing to determine the generated electron beam position.

[0143] In a preferred configuration the coupling structure is a tray (1) with fasteners adapted to the LINAC.

[0144] The rotation device comprises; bearings (2) or bushings, a gear belt (9) is connected to a geared motor (10) with the gear of the central axis (7) that is fixed to the coupling structure by bolts (4), the gear belt (9) is tensioned by another pulley (40), with axle slidable to a rail groove (41), which is fixed by bolts or screws (42).

[0145] In another preferred configuration, the rotation device is constructed entirely with gears (11), (9) which are connected directly to the geared motor (10) with the central gear (7), wherein the gear (7) is part of the central axis (5), wherein, the mechanism of the rotation device is positioned above the coupling device.

[0146] In another preferred configuration, the magnetic electron deflection system (503), is formed by a first magnetic deflection device (13) that deflects the electron beam between 60° and 100° with respect to the direction of the incident electron beam and a second magnetic deflection device (14), of reverse polarity to the first magnetic deflection device (13), deflects the electrons towards a focal point located on the optical axis, which comprise magnets that have a joint intensity between 0.3 T and 1.2 T, wherein, the entire magnetic deflection system (503) is fixed to a support structure (17), wherein some electron beam correction elements (504).

[0147] In another preferred configuration, the output of each magnetic deflection device is positioned a trajectory aligning magnetic quadrupole (15, 18) of the trajectory electron beam (18) and/or dipole (74) that aligns the electron beam.

[0148] In another preferred configuration, the output of the first magnetic deflection device (13) and/or in front of the first quadrupole (15) is positioned at least one magnetic dipole (74) that focuses the trajectory of the electron beam.

[0149] In another preferred configuration, the output of the second magnetic deflection device (14) is positioned a magnetic dipole (74) that focuses the trajectory of the electron beam, wherein, the deflection system (503) lies in a vacuum outer housing (45), which is adapted to the configuration of the magnets, wherein, the first magnetic deflection device (13) is attached to the box inlet wall in a direction perpendicular to the incident electron beam and the second magnetic deflection device (14) is inclined to more than 0°, clockwise, with respect to the first deflection device (13).

[0150] The magnetic deflection devices (13, 14) are inclined so that the electron beam emerges from the first magnetic deflection device (13) and deflects in an angle close to 90°, wherein, the magnetic deflection devices (13, 14) are constructed with permanent magnets (64).

[0151] In another preferred configuration, the magnetic deflection devices (13, 14) are constructed with electromagnets, wherein, each magnetic deflection device (13, 14) is formed of two magnets (64), wherein each magnet has a magnetic field intensity between 0.2 T and 0.7 T located facing its opposite poles on its polar faces, a non-magnetic lateral support (65), with an elongated hole in the central area, allow positioning the magnets (64) thanks to protrusions that prevent them from joining; C-shaped field closing element (66), located on the sides of the magnets, close the magnetic circuit.

[0152] In addition, each of the magnetic deflection devices (13, 14) has a non-magnetic part with a non-magnetic support with central stand (67), so that when the electron beam enters laterally through the area of the central hole of at least one of the magnetic deflection devices (13,14) the beam exits through the same face through which it entered.

[0153] On the other hand, quadrupole (15, 18) manufactured with permanent magnets is used.

[0154] In addition, the at least one dipole (74) is manufactured with permanent magnets.

[0155] The electron beam correction elements (504), comprise quadrupoles (18) and magnetic dipoles (74) based on permanent magnets.

[0156] In another preferred configuration, the magnetic deflection devices (13, 14) have an intensity greater than 0.5 T, in another more preferred configuration the magnetic deflection devices (13, 14) have an intensity greater than 1 T.

[0157] The shape of the pair of permanent magnets that make up the magnetic deflection devices (13, 14) are of curved and irregular cuts on one of their faces (77, 78).

[0158] The magnetic deflection devices (13, 14) have at least one curved field closing element (94), which further comprise a curve at each of their distal ends.

[0159] In another preferred configuration, the magnetic deflection devices (13, 14) are electrically energized by a rotary contact (58) that connects it to conductive rings (59) that are connected with the electrical terminals of the head of the external radiotherapy device, in addition it has a non-magnetic S-shaped vacuum electron tube (16) with windows (68) at its ends. On the other hand, the windows 68 are from beryllium, as it is a light material.

[0160] In addition, the windows 68 are heat conductive.

[0161] In another preferred configuration, the beam guide has an S-shaped tube (69) or it has a telescopic (70) and cylindrical S-shaped tube or it has a flexible and telescopic tube (72).

[0162] In another preferred configuration, the focus control system comprises magnetic deflection devices (13, 14) that are solidly fixed to a support structure (17).

[0163] In another preferred configuration, the focus control system comprises a first stepper motor (12) that moves the second magnetic deflection device (14) along a rail (61) of the second magnet linearly displacing the second magnetic deflection device (14) with respect to the rotational axis along the line of the trajectory of the electron beam, wherein the second magnetic deflection device (14) is joined in solidarity with the collimator (25).

[0164] In another preferred configuration, the focus control system comprises a second magnetic deflection device (14) rotated by driving a second angular motor (22) and the collimator (25) is angularly displaced by means of a second angular motor (22a) and linearly displaced by means of a linear motor (22L) and the collimator rail (21).

[0165] In another preferred configuration, the focus control system comprises a first stepper motor (12) that moves the second magnetic deflection device (14) along a rail of the second magnet (61) linearly displacing the magnetic deflection device (14) with respect to the axis of rotation along the line of the trajectory of the electron beam, wherein the second magnetic deflection device (14) rotates, by driving a second angular motor (22) and the collimator (25) is angularly displaced by means of a second angular motor (22a) and is linearly displaced by means of a linear motor (22L) and the collimator rail (21).

[0166] In another preferred configuration, collimator (25) comprises:

[0167] a. a septa tube (83) with a septa (84) crossing the collimator;

[0168] b. a heat sink (87), which envelops the collimator (25);

[0169] c. a radiation attenuator with an attenuation material (85) with a Z greater than 70, which radially envelops the septa tube (83);

[0170] d. a white filter disc (19) movable, inserted within said collimator (25) in a side compartment (90) to allow free passage of the electrons, wherein the white filter disc (19) is displaced to the septa (84) to generate X-ray photons.

[0171] The collimator (25) further comprises displacement means (89) that translate the white filter disc (19) to one of two positions, which are in the side compartment (90) to allow free passage of the electrons or the septa (84) to generate X-ray photons.

[0172] In another preferred configuration, the heat sink (87) is manufactured of materials with thermal conductivity such as aluminum, copper, boron, tin or titanium or broth or alloy thereof.

[0173] On the other hand, the heat sink 87 further comprises concentric cylinders 82 that transmit heat homogeneously, outwardly.

[0174] On the other hand, the heat sink 87 further comprises dissipation rings 86 for dissipating heat outward.

[0175] In another preferred configuration, the displacement means (89) are driven by manual means, such as a peg (92) that moves along the curved groove (91) and is returned by a spring (90).

[0176] In another preferred configuration, the displacement means (89) are driven by a motor and a wired or wireless communication means.

[0177] The white filter disc (19) is manufactured of tungsten or lead or silver or gold or tin, or alloys thereof.

[0178] In another preferred configuration, an external fan for improving thermal dissipation.

[0179] On the other hand, a shielding system 507 comprising a head shielding (19) which completely covers the second magnetic deflection device (14), which prevents radiation leakage of X-ray photons.

[0180] In another preferred configuration, a counterweight (505) and control system, comprising a support counterweight (26), a stepper motor counterweight (28), a counterweight (30), wireless communication means, a wireless communication compartment (31) with a control compartment (29) for controlling the stepper motors, and battery compartment (27) that energizes all the devices that are in rotation.

[0181] The electron deflection system (503) is in an open environment.

[0182] In another preferred configuration, a first operation control controls the operation of the LINAC to enable the operation plan, a second control to control the rotation speed and stepper motors that allow the variation of the position of the focus and of the device that cuts the electron beam.

[0183] In another preferred configuration, collimator (25) comprises at its distal end an extender element (79), for electron output that minimizes the dispersion of said electrons in the air.

[0184] In another preferred configuration, a dosimetric monitoring system (85), which is located at the bottom of the collimator (25) comprising two gas ionization chambers (80) with aluminized windows, to monitor the radiation intensity delivered by the device (500).

[0185] In another preferred configuration, the bottom of a support structure (17) is attached to at least two laser guides pointing towards the focus.

LIST OF PARTS COUPLING TRAY

[0186] 2. Center axis support [0187] 3. Bearings (2) [0188] 4. Fastening means [0189] 5. Center axis [0190] 6. Window [0191] 7. Center axis gear [0192] 8. Coupling flange [0193] 10 [0194] 9. Gear belt [0195] 10. Geared motor [0196] 11. Pulley gear motor [0197] 12. First Motor L [0198] 13. First magnetic deflection device. [0199] 14. Second magnetic deflection device. [0200] 15. First quadrupole trajectory rectifier [0201] 16. S-shaped vacuum electron tube [0202] 17. Support structure [0203] 18. Second trajectory rectified quadrupole [0204] 19. White disc/filter 19a. White disc for electron impact; 19b. Electron filter and heat sink. [0205] 20. Head shielding [0206] 21. Collimator support base rail [0207] 22. Second Motor [0208] 23. Collimator support base [0209] 24. Collimator holding housing [0210] 25. Collimator [0211] 26. Counterweight support [0212] 27. Battery compartment [0213] 28. Counterweight stepper motor [0214] 29. Control compartment [0215] 30. Counterweight [0216] 31. Wireless communication compartment [0217] 32. Counterweight screw [0218] 33. Counterweight adjustable support [0219] 30 [0220] 34. Sealed outer casing [0221] 35. Counterweight support base [0222] 36. Tensioning pulley [0223] 37. Fixing screw [0224] 38. Groove rail [0225] 39. Flange fastening ring [0226] 40. Window [0227] 41. Outer housing [0228] 42. Groove for electron entry [0229] 43. Collimator septa [0230] 44. Collimator rail base [0231] 45. White net disc [0232] 46. Electron Filter [0233] 47. Rotary contact [0234] 48. Conductive rings [0235] 49. Weight Compensator Placement Base [0236] 50. Dynamic Beam Brake [0237] 51. Sheets of metal [0238] 52. Solenoid [0239] 53. Permanent magnet [0240] 54. Side stand non-magnetic support [0241] 55. Field closing element [0242] 56. Central stand non-magnetic support [0243] 57. Beryllium tube windows [0244] 58. Fixed S tube [0245] 59. Telescopic S tube [0246] 60. Flexible and telescopic S tube [0247] 61. Second magnet rail [0248] 62. Joint element of second magnet with head [0249] 63. Positioning laser lights [0250] 64. Permanent dipolar magnet [0251] 65. Second collimator stepper motor [0252] 66. Axis for collimator angular rotation [0253] 67. Permanent magnet holder non-magnetic mono-block [0254] 68. Quadrupole set [0255] 69. Quadrupole support non-magnetic core [0256] 70. Field closing ferromagnetic cylinder [0257] 71. Four permanent magnets [0258] 72. Non-magnetic base [0259] 73. Dipole non-magnetic housing [0260] 74. Dipole set [0261] 75. Permanent toroidal circular magnet [0262] 76. Support [0263] 77. Deflector magnet 1 with cut [0264] 78. Deflector magnet 2 with cut [0265] 79. Electron Extender Tube [0266] 80. Ionization cameras [0267] 81. Shielding for scattered photons of the electron source [0268] 82. Conductive concentric cylinders [0269] 83. Low-Z septa conductive cylinder (Al) [0270] 84. Septa [0271] 85. Solid concentric cylinders of shielding material (W or Pb) [0272] 86. Ventilation vanes [0273] 87. Dissipation system [0274] 88. Electron filter [0275] 89. Displacement means of white filter disk [0276] 90. Side compartment [0277] 91. Curved groove of peg [0278] 92. Peg [0279] 93. Lock [0280] 94. Input coupling means [0281] 95. Electron input rectangular conical groove [0282] 96. Sealing ring [0283] 97. Shielding [0284] 98. Collimator output coupling means [0285] 99. External shielding housing [0286] 500. Ionizing radiation fluence concentrator device [0287] 501. External structure [0288] 502. Interior structure [0289] 503. Deflection system [0290] 504. Electron beam correction elements [0291] 505. Counterweight system