APPLICATOR AND APPLICATOR SYSTEM FOR USE WITH A RADIATION THERAPY DEVICE

Description

[0001] The present invention lies in the field of medical radiotherapy and relates to an applicator for a medical radiotherapy device, an applicator system for a medical radiotherapy device and a method for using an applicator or an applicator system.

[0002] Medical radiotherapy devices exist for the local irradiation of a body to be treated with radiation, particularly X-rays. In the field of X-ray therapy, there are therapies in which X-rays are to be generated inside a human or animal body in proximity to the tissue to be treated.

[0003] An exemplary radiation therapy device comprises a particle beam system capable of generating a high-energy particle beam. The particle beam is directed through a tube of the radiation therapy device, several centimeters long, onto an X-ray material located at the end of the tube. The interaction of the particle beam with the X-ray material generates X-ray radiation, which is intended for tissue treatment.

[0004] To apply the X-ray radiation generated by the X-ray material at the tip of the tube inside the body, the tube is inserted into the body. For this purpose, the tube is surrounded by an applicator that can be attached to the radiotherapy device. This applicator acts as a sterile barrier and protects the tube of the radiotherapy device.

[0005] Such applicators must be made of a material approved for medical applications (e.g., Ultem ® ). Traditionally, an applicator is formed in one piece, for example, by milling the final shape of the applicator from a blank. The material milled from the blank cannot usually be reused. Accordingly, the manufacture of an applicator is complex, requiring high-precision machining, and expensive, as a large portion of the blank is scrap.

[0006] X-ray therapy typically requires several different applicators of different sizes and shapes. Purchasing a suitable set of applicators is therefore expensive, especially if the applicators are made as a single piece.

[0007] Accordingly, there is a need for a set of applicators that is easier and more cost-effective to manufacture. Accordingly, it is an object of the present invention to provide a set of applicators that can be manufactured more easily and cost-effectively and used more flexibly.

[0008] The publications US 2014 / 0206925 A1; "Brachytherapy-Applicators and Accessories" dated January 1, 2011, accessed on January 25, 2017, from https: / / www.varian.com / sites / default / files / resource_attachments / Brachytherapy_Applicators_Accessories_Catalogue_0_0.pdf; EP 2 335 777 A2; DE 10 2012 002 466 A1; and DE 11 2013 005 144 B4 are part of the relevant prior art and concern applicators, devices, and systems in the field of brachytherapy.

[0009] None of them teach an inventive design of the applicator head according to claim 1.

[0010] The problem is solved by an applicator according to claim 1.

[0011] Furthermore, the object is achieved by an applicator system comprising a plurality of such applicators, wherein the applicator body of all applicators is the same. The applicators of the applicator system can have different sizes and / or shapes if the respective applicator heads are mounted on the applicator body.

[0012] Only a method not belonging to the invention is described, which comprises: providing such an applicator, wherein the applicator head is mounted on the applicator body; after providing, damagingly dismounting the applicator head from the applicator body; and after dismounting, mounting the applicator head or another applicator head on the applicator body. The applicator according to the invention is characterized in that the applicator head can be mounted on the applicator body without causing damage and can be dismounted therefrom without causing damage. Therefore, one and the same applicator body can be used with different applicator heads. This means that different applicator heads can be mounted on the same applicator body without causing damage and can be dismounted therefrom without causing damage.A set of different applicators, which is also referred to herein as an applicator system, can therefore be easily provided by a single applicator body and different applicator heads, since the different applicator heads can be mounted on and removed from one and the same applicator body without causing damage.

[0013] For example, damage-free assembly and disassembly means that the applicator head and the applicator body have the same physical shape in both the assembled and unassembled state. This means, for example, that neither the shape of the applicator head nor the shape of the applicator body are changed by assembly and disassembly.

[0014] Damage-free assembly and damage-free disassembly may also or alternatively mean that the applicator head and the applicator body can be assembled and disassembled without additional items (e.g. adhesive).

[0015] Examples of mechanical connections between the applicator head and the applicator body that can be securely connected (non-damaging assembly) and disconnected (non-damaging disassembly) include plug connections, screw connections, force-locking connections, positive connections, and the like. Examples of mechanical connections that cannot be securely connected and disconnected are material connections, such as adhesive bonds.

[0016] The applicator can be made of a material approved for medical purposes. One such material is Ultem®. The individual components of an applicator can be made of the same material. In particular, the applicator head and the applicator body can be made of the same material. In particular, the applicator head elements of the applicator head and the applicator body can be made of the same material. The applicator head can comprise multiple applicator head elements that have different absorption behaviors with respect to the radiation used by the radiotherapy device.

[0017] Embodiments of the invention are explained in more detail below with reference to the figures. Herein: Figure 1A is a schematic representation of a cross section of a radiotherapy device and an exemplary applicator in a disassembled state, Figure 1B is a schematic representation of a cross section of the Figure 1A shown applicator in an assembled state, wherein the radiotherapy device is inserted into the applicator, Figure 2A is a schematic representation of a cross section of another exemplary applicator in a disassembled state, Figure 2B is a schematic representation of a cross section of the in Figure 2A shown applicator in an assembled state, Figure 3A is a schematic representation of a cross section of another exemplary applicator in a disassembled state, Figure 3B is a schematic representation of a cross section of the Figure 3Ashown applicator in an assembled state, Figure 4A a schematic representation of a cross section of another exemplary applicator in a disassembled state, Figure 4B a schematic representation of a cross section of applicator head elements of the in Figure 4A shown applicator in a disassembled state, with the cross section of the Figure 4B perpendicular to the cross section of the Figures 4A and 4C oriented, Figure 4C a schematic representation of a cross section of the Figure 4A shown applicator in an assembled state, and Figure 5 shows an exemplary method for using an applicator.

[0018] In the following, a first embodiment of an applicator 1 for a medical radiotherapy device 3 is described with reference to the Figures 1A and 1B described. Figure 1Ashows a schematic representation of a cross section through the applicator 1 and the radiotherapy device 3, wherein the applicator 1 is shown in a disassembled state, ie in a state in which an applicator head 13 of the applicator 1 is not mounted on an applicator body 11 of the applicator 1, and the radiotherapy device 3 is not inserted into the applicator 1. Figure 1B shows a schematic representation of a cross section through the applicator 1 and the radiotherapy device 3, wherein the applicator 1 is shown in an assembled state, ie in a state in which the applicator head 13 is mounted on the applicator body 11 and the radiotherapy device 3 is inserted into the applicator 1.

[0019] The radiotherapy device 3 comprises a main body 5 with a tube 7 extending away from the main body 5. At an end 9 of the tube 7 remote from the main body 5, an X-ray material can be arranged (inside the tube 7), which is suitable for emitting X-ray radiation.

[0020] The radiotherapy device 3 is configured to generate the X-ray radiation using the X-ray material. For this purpose, the radiotherapy device 3 can comprise a particle beam system (not shown in the figures) arranged inside the main body 5, which directs a particle beam inside the tube 7 onto the X-ray material, which emits the X-ray radiation upon interaction with the particle beam.

[0021] The applicator 1 comprises an applicator body 11 and an applicator head 13. The applicator body 11 and the applicator head 13 are separate parts, each formed in one piece.

[0022] The applicator body 11 comprises an adapter section 15, which is configured to be connected to the radiotherapy device 3. In particular, the adapter section 15 is configured to be connected to the main body 5 of the radiotherapy device 3. In the Figure 1A In the example shown, the adapter section 15 is a substantially tubular section with an interior space 17 in which the main body 5 of the radiotherapy device 3 can be at least partially arranged.

[0023] The applicator body 11 further comprises a central section 19, which adjoins the adapter section 15. The central section 19 has a conically tapered tubular shape. The central section 19 surrounds an interior space 21, which is connected to the interior space 17 of the adapter section 15.

[0024] The applicator body 11 further comprises a connecting section 23. The connecting section 23 has a substantially tubular shape. An interior space 25 enclosed by the connecting section 23 adjoins the interior space 21 of the central section 19. The connecting section 23 serves to connect (mount) the applicator body 11 to the applicator head 13.

[0025] The applicator head 13 has in the example of Figure 1Aa substantially spherical outer shape. However, the outer shape of the applicator head 13 can also have any other desired outer shape, for example, an ellipsoidal shape. The shape of the applicator head is selected depending on the body to be treated. During a therapeutic application (irradiation), the applicator 1 is inserted into the body to be treated so that at least a portion of the applicator head 13 is inserted into the body to be treated. The surface of the applicator head 13 supports the tissue to be treated and also serves to generate a desired radiation profile.

[0026] The applicator head 13 comprises a connecting section 27. In the Figure 1A In the example shown, the connecting portion 27 of the applicator head 13 is a cylindrical recess in the interior of the applicator head 13, which extends to the surface.

[0027] The applicator head 13 further comprises an interior space 31 in which the end 9 of the radiotherapy device 3 is arranged when the applicator head 13 is mounted on the applicator body 11. In the Figures 1A and 1B In the example shown, the recess providing the connecting portion 27 is part of the interior space 31.

[0028] The connecting section 23 of the applicator body 11 and the connecting section 27 of the applicator head 13 together form a first mounting device 29, which is configured to provide a damage-free, detachable mechanical connection between the applicator head 13 and the applicator body 11. In the Figure 1AIn the example shown, the first mounting device 29 provides a plug-in connection that can be formed by the connecting sections 23 and 27. This means that the applicator head 13 can be mounted on the applicator body 11 (can be mechanically connected thereto) by inserting the connecting section 23 into the connecting section 27, whereby a force-fitting connection is formed between the applicator head 13 and the applicator body 11 by frictional engagement. This mechanical connection can be released without damage by pulling the applicator head 13 off the applicator body 11.

[0029] In Figure 1B The applicator head 13 is mounted on the applicator body 11. Assembly is carried out by means of the plug connection described above through the connecting sections 23 and 27. The applicator 1 is thus in an assembled state.

[0030] In addition, the radiotherapy device 3 is inserted into the assembled applicator 1. The main body 5 of the radiotherapy device 3 is partially located within the interior space 17 of the adapter section 15 of the applicator body 11. Furthermore, the tube 7 of the radiotherapy device 3 passes through the interior spaces 21 and 25 of the applicator 1 and exits the applicator 1 from a front end of the connecting section 23. The end 9 of the radiotherapy device 3 is located within the interior space 31. Thus, the end 9 of the radiotherapy device 3 is located approximately in the center of the applicator head 13.

[0031] The first mounting device 29 is designed to provide a mechanical connection between the applicator head 13 and the applicator body 11 that can be released without damage. As in the example in Figure 1AAs shown, the connecting portions 23 and 27, which form the first mounting device 29, are formed as portions of the applicator head 13 and the applicator body 11. Therefore, the applicator head 13 and the applicator body 11 are configured such that the applicator head 13 can be mounted on and removed from the applicator body 11 without damage.

[0032] This configuration of the applicator 1 allows the use of several different applicator heads with one and the same applicator body 11. A set of applicators, also referred to as an applicator system, can therefore be provided by an applicator body and several (different) applicator heads, wherein each of the applicator heads can be individually mounted on the applicator body and removed from it without causing damage.

[0033] A second embodiment of an applicator 101 is described below with reference to the Figures 2A and 2B described, where Figure 2Ashows a schematic representation of a cross section through the applicator 101 in a disassembled state, while the Figure 2B a schematic representation of a cross section through the applicator 101 in an assembled state.

[0034] The applicator 101 comprises an applicator body 111 and an applicator head 113. The applicator body 111 differs from that shown in Figure 1 The applicator body 11 shown essentially differs only in the specific design of the connecting section. Accordingly, only the differences to the Figure 1A The description of the applicator body 11 shown in the drawing applies to components with the same reference numerals. Figure 1A . The applicator body 111 comprises a connecting section 123, which in the Figure 2A shown example is formed by an external thread.

[0035] Furthermore, the applicator 101 comprises the applicator head 113, the outer shape of which corresponds to the applicator head 13 in Figure 1A The applicator head 113 comprises a connecting section 127, which in the Figure 2A In the example shown, it is an internal thread that fits the connecting portion 123 (external thread) of the applicator body 111. The connecting portion 127 lies within the substantially spherical surface of the applicator head 113. The connecting portions 123 and 127 together form the first mounting device 29.

[0036] The applicator head 113 can be mounted on the applicator body 111 without damage by screwing the connecting sections 123 and 127 together, as shown in Figure 2B The applicator head 113 can be removed from the applicator body 111 without causing damage by unscrewing the applicator head 113 from the applicator body 111, as shown in Figure 2A shown in the Figures 2A and 2B In the example shown, the first mounting device 29 is a screw connection.

[0037] With the Figures 2A and 2B The same effects can be achieved with the applicator 101 shown as with the one shown in the Figures 1A and 1B shown applicator 1.

[0038] A third embodiment of an applicator 201 is described below with reference to the Figures 3A and 3B described, where Figure 3A shows a schematic representation of a cross section through the applicator 201 in a disassembled state, while the Figure 3B a schematic representation of a cross section through the applicator 201 in an assembled state.

[0039] The applicator 201 comprises the applicator body 111 and an applicator head 213. The applicator body 111 corresponds to the applicator body described in connection with the applicator 101.

[0040] The outer shape of the applicator head 213 corresponds to that of the applicator head 13 in Figure 1A The applicator head 213 comprises a connecting portion 227 which is in the Figure 3A In the example shown, it is an internal thread that fits the connecting portion 123 (external thread) of the applicator body 111. The connecting portion 227 lies outside the substantially spherical surface of the applicator head 213. The connecting portions 123 and 227 together form the first mounting device 29.

[0041] The applicator head 213 can be mounted on the applicator body 111 without damage by screwing the connecting sections 123 and 227 together, as shown in Figure 3B The applicator head 213 can be removed from the applicator body 111 without causing damage by unscrewing the applicator head 213 from the applicator body 111, as shown in Figure 3A shown in the Figures 3A and 3B In the example shown, the first mounting device 29 is a screw connection.

[0042] With the Figures 3A and 3B The same effects can be achieved with the applicator 201 shown as with the Figures 1A, 1B , 2A and 2B shown applicators 1 and 101.

[0043] A fourth embodiment of an applicator 301 is described below with reference to the Figures 4A to 4C described.

[0044] Figure 4A shows a schematic representation of a cross section through the applicator 301 in a disassembled state. Figure 4B shows a schematic representation of a cross-section of applicator head elements of the Figure 4A shown applicator 301 in a disassembled state, wherein the cross section of the Figure 4B perpendicular to the cross section of the Figures 4A and 4C oriented. Figure 4C shows a schematic representation of a cross section through the Figure 4A shown applicator 301 in an assembled state.

[0045] The applicator 301 comprises an applicator body 311 and an applicator head 313.

[0046] The applicator body 311 differs from that in Figure 1A shown applicator body 11 essentially only in that the connecting section 323 of the applicator body 311 has a substantially spherical outer shape.

[0047] The applicator head 313 comprises several applicator head elements. Figures 4A to 4C In the example shown, the applicator head 313 comprises three separate applicator head elements 313A, 313B and 313C. Figure 4B shows a representation of the applicator head element 313A in cross section AA, which is perpendicular to the plane of the Figure 4A oriented along the direction of the arrow, ie in Figure 4A to the left. Figure 4B further shows a representation of the applicator head element 313B in cross section BB, which is perpendicular to the plane of the Figure 4A oriented along the direction of the arrow, ie in Figure 4A To the right. Figure 4B further shows a representation of the applicator head element 313C in cross section CC, which is perpendicular to the plane of the drawing of Figure 4A oriented along the direction of the arrow, ie in Figure 4A To the right.

[0048] The applicator head element 313A has a substantially hemispherical outer shape with a hemispherical recess 315 corresponding to the size of the connecting portion 323 of the applicator body 311. The applicator head element 313A further has an internal thread 317.

[0049] The applicator head element 313B has a substantially spherical segment-shaped outer shape and also has two recesses 319 and 321. The recess 319 is a spherical segment-shaped recess, the shape and size of which are adapted to the size of the connecting section 323 of the applicator body 311. The recess 321 is a cylindrical recess adapted to the shape and size of the central section 19 of the applicator body element 311. The applicator head element 313B further comprises an external thread 325. The external thread 325 is adapted to the internal thread 317.

[0050] The applicator head element 313C essentially corresponds to the applicator head element 313B, wherein the external thread 325 of the applicator head element 313C and the external thread 325 of the applicator head element 313B are matched to one another in such a way that they result in a functionally cooperating external thread which can be screwed into the internal thread 317 of the applicator head element when one side 326B of the applicator head element 313B (see Figure 4B ) and one side 326C of the applicator head element 313C are placed together

[0051] The applicator head elements 313A, 313B and 313C are designed such that they can be assembled and disassembled without damage. Figures 4A to 4CIn the example shown, the internal thread 317 and the external thread functionally cooperating from the external threads 325 of the applicator head elements 313B and 313C provide a second mounting device configured to provide a damage-free, releasable mechanical connection between the applicator head elements 313A to 313C. For example, the applicator head elements 313A to 313C are non-damagingly mounted to one another by placing the applicator head elements 313B and 313C against one another at the sides 326B and 326C to form the functionally cooperating external thread, which is then screwed into the internal thread 317 provided on the applicator head element 313A. Such a situation, in which the applicator head elements 313A to 313C are mounted to one another, is shown in Figure 4C shown.

[0052] The applicator head 313 can be mounted on the applicator body 311 without damage as follows: The applicator head element 313A is placed on the connecting section 323 of the applicator body 311, wherein the connecting section 323 is inserted into the recess 315 of the applicator head element 313A. The applicator head element 313B and the applicator head element 313C are placed against each other at the sides 326B and 326C, wherein the central section 19 of the applicator body 311 passes through the recess 321. Here, the applicator head element 313A and the placed applicator head elements 313B and 313C are separated from each other along a longitudinal direction of the applicator (in Figure 4Ain the direction from left to right) so that the external threads 325 do not collide with the applicator head element 313A when the applicator head elements 313B and 313C are placed against one another. In this state, the connecting section 323 can already be partially inserted into the recesses 319. Subsequently, the applicator head element 313A and the adjacent applicator head elements 313B and 313C are pushed against one another along the longitudinal direction. Subsequently, the adjacent applicator head elements 313B and 313C are screwed to the applicator head element 313A by rotating the adjacent applicator head elements 313B and 313C relative to the applicator head element 313A about the longitudinal axis, whereby the internal thread 317 and the functionally cooperating external thread engage with one another.

[0053] The applicator head elements 313A to 313C can be disassembled from each other without causing damage by loosening the screw connection, as shown in Figure 4A is shown.

[0054] The Figures 4A to 4C show an example of the second mounting device in the form of a screw connection. However, the second mounting device can also be provided by another type of connection, in particular in the form of a plug-in connection, a force-locking connection, or a form-locking connection.

[0055] In the Figures 4A to 4CIn the example shown, the recess 315 of the applicator head element 313A and the recess 319 of the applicator head elements 313B and 313C are designed such that the connecting section 323 of the applicator body 311 can be at least partially, in particular substantially completely and flush, enclosed by the applicator head elements 313A to 313C. As a result, the radiation characteristic of the applicator head 313 essentially corresponds to the radiation characteristic of a one-piece applicator head with the same external shape.

[0056] In other words, the applicator head elements 313A to 313C can be arranged around the connecting section 323 and then connected to each other (by means of the second mounting device), as shown in Figure 4Cis shown. When assembled together, the applicator head elements 313A to 313C form a spherical shell with matching recesses for the connecting section 323 and the central section 19 of the applicator body 311. When the applicator head elements 313A to 313C are assembled together in this way and are arranged around the connecting section 323, as shown in Figure 4C As shown, this creates a positive connection between the applicator head 313 formed from the applicator head elements 313A to 313C and the applicator body 311. This positive connection is an example of the first mounting device 29. In this way, by means of the mechanical connection between the applicator head elements 313A to 313C provided by the second mounting device, a mechanical connection that can be released without damage is also formed between the applicator head 313 and the applicator body 311.

[0057] In the example of Figures 4A to 4C The connecting portion 323 has a substantially spherical outer shape. Other outer shapes are possible, in particular a substantially ellipsoidal outer shape.

[0058] In the example of Figures 4A to 4C The applicator head 313, which is formed by the applicator head elements 313A to 313C mounted on one another, has a substantially spherical outer shape. Other outer shapes are possible, in particular a substantially ellipsoidal outer shape.

[0059] The individual shapes of the components of the applicators described above are not limited to the shapes shown in the embodiments.

[0060] Figure 5 shows an exemplary method for using one of the applicators described herein.

[0061] In a first step S1, an applicator is provided. The applicator can, for example, be one of the previously described applicators 1, 101, 201, or 301. For the purposes of this description, reference is made to applicators 1 and 301.

[0062] In a subsequent step S2, a body to be treated is irradiated using the applicator 1 provided in step S1 and a radiotherapy device 3. As exemplified in Figure 1B As shown, the applicator head 13 is mounted on the applicator body 11 and the radiotherapy device 3 is inserted into the applicator 1 via the adapter section 15, so that the Figure 1BThe situation outlined is achieved. The radiotherapy device 3, to which the applicator 1 is attached in this way, is now introduced into the body to be treated, with the applicator head element 13 being at least partially inserted into the body to be treated. Subsequently, radiation, for example X-rays, is generated by the radiotherapy device 3 at the end 9 and delivered to the body to be treated via the applicator head 13.

[0063] After the irradiation in step S2, the applicator can be disassembled from the radiotherapy device in step S3, as described in Figure 1A is shown.

[0064] In a subsequent step S4, the applicator head 13 or the applicator head elements 313A to 313C are dismantled from the applicator body 11 or 311 without causing any damage. Figures 1A and 1BThe applicator head 13 is removed from the applicator body 11 by loosening the plug connection between the applicator head 13 and the applicator body 11. In the case of Figures 4A to 4C the applicator head elements 313A to 313C are disassembled from the applicator body 311 without causing any damage by first loosening the screw connection between the applicator head elements 313A to 313C and then loosening the positive connection between the applicator head elements 313A to 313C and the applicator body 311.

[0065] In a subsequent step S5, the applicator body 11 can be cleaned. Thus, the applicator body 11 can be reused. The applicator body 11 forms the largest part of the applicator 1, and it is therefore particularly advantageous to use the applicator body 11 multiple times. However, the applicator head or the applicator head elements can be significantly smaller and therefore less expensive than the applicator body. The applicator head or the applicator head elements can therefore be used as disposable products, i.e., products that are used only once.

[0066] To prepare for further irradiation, an applicator can be prepared according to step S6 by mounting a different applicator head or different applicator head elements on the cleaned applicator body. Alternatively, the applicator head or applicator head elements can be cleaned and remounted on the cleaned applicator body in step S6. In this way, all parts of an applicator can be reused.

Claims

1. Applicator (301) for a medical radiotherapy device (3) for performing therapy by means of radiation, the applicator (301) comprising: an applicator head (313) and an applicator body (311), wherein the applicator head and the applicator body are designed such that the applicator head can be assembled on, and disassembled from, the applicator body, in each case without damage; wherein the applicator head (313) comprises at least two separate applicator head elements (313A, 313B, 313C), which are designed such that they can be assembled on, and disassembled from, one another, in each case without damage.

2. Applicator (301) according to Claim 1, wherein the applicator head (313) and the applicator body (311) comprise a first assembling mechanism (29), which is configured to provide a mechanical connection between the applicator head and the applicator body, which can be released without damage.

3. Applicator (301) according to Claim 2, wherein the first assembling mechanism (29) provides a screw connection, a plug connection, an interlocking connection, a force-fit connection or the like between the applicator head and the applicator body.

4. Applicator (301) according to any of Claims 1 to 3, wherein the applicator head elements (313A, 313B, 313C) comprise a second assembling mechanism (317, 325), which is configured to provide a mechanical connection between the applicator head elements, which can be released without damage.

5. Applicator (301) according to any of Claims 1 to 4, wherein the applicator head elements (313A, 313B, 313C) and the applicator body (311) are designed such that a mechanical connection between the applicator body and the applicator head elements, which can be released without damage, is established when the applicator head elements are assembled on one another.

6. Applicator (301) according to any of Claims 1 to 5, wherein a section (323) of the applicator body is substantially surrounded by the applicator head when the applicator head (313) is assembled on the applicator body (311); and wherein the section (323) has a substantially spherical external shape or a substantially ellipsoid external shape.

7. Applicator (301) according to any of Claims 1 to 6, wherein the applicator head (313) has a substantially spherical external shape or a substantially ellipsoid external shape when the applicator head is assembled on the applicator body (311).

8. Applicator (301) according to any of Claims 1 to 7, wherein the applicator body (311) and the applicator head (313) are made of the same material.

9. Applicator according to any of Claims 1 to 8, wherein the applicator head elements have different absorption characteristics in respect of the radiation.

10. Applicator according to any of Claims 1 to 9, wherein the applicator body (311) is formed in one piece.

11. Applicator according to any of Claims 1 to 10, wherein the applicator body (311) comprises an adapter section (15) which is configured to be connected to the radiotherapy device (3); wherein the applicator body (311) further comprises a central section (19) which adjoins the adapter section (15) and surrounds an interior space (21) that is associated with an interior space (17) of the adapter section (15); wherein the applicator body (311) further comprises a connecting section (323) which encloses an interior space (25) that adjoins the interior space (21) of the central section (19); wherein a tube (7) of the radiotherapy device (3) passes through the interior space (21) of the central section (19) and the interior space (25) of the connecting section (323) when the radiotherapy device (3) is inserted into the applicator (311).

12. Applicator according to Claim 11, wherein the adapter section (15) is a substantially tubular section with the interior space (17), in which a main body (5) of the radiotherapy device (3) is at least partially arrangeable.

13. Applicator system comprising a plurality of different applicators according to any of Claims 1 to 12, wherein the applicator body of all applicators is the same.

14. Applicator system according to Claim 13, wherein the applicators have different sizes and / or shapes when the respective applicator heads are assembled on the applicator body.