DESCRIPTION

Technical field of the utility model

The present utility model refers to a modular positioning system, configured to house at least a portion of a patient’s anatomical area. The positioning system is intended to be used in combination with radiotherapy devices, and specifically with hybrid radiotherapy devices with magnetic resonance imaging.

In particular, the model refers to a positioning system designed to keep the patient’s anatomical area to undergo radiotherapy in a stable and fixed position, or to image acquisition procedures preparatory to the latter treatment.

The following description will relate to the specific field of application of radiotherapy treatments, however the model can be applied to any field concerning the provision of medical and non-medical treatments to the human body, where a predetermined positioning and immobility of the target anatomical area is required to be ensured.

Background

Radiation therapy is a type of physical therapy which uses ionizing radiation for tumour treatment. Such radiations are traditionally and more commonly delivered by devices known as ‘linear accelerators’. The radiotherapy treatment requires the patient to undergo an image acquisition protocol of the anatomical area where the volume target of the treatment is located (acquisition of the simulation imaging and processing of the treatment plan), and subsequently to deliver radiation to the same anatomical area. Such two operations are carried out in succession. During the delivery of radiation, the patient must necessarily remain in the same position defined during the image acquisition. For the correct execution of the treatment, the patient must remain motionless for the entire duration of the single radiotherapy fraction, which may vary between 5 and 50 minutes, depending on the type of treatment technology used.

In order to ensure patient immobility, immobilization and repositioning systems or aids, specifically designed according to the anatomical area being treated, are typically used. In particular, such systems are customized for the individual patient (e.g. thermoplastic masks).

To the present day, alongside traditional linear accelerators, hybrid radiotherapy devices with magnetic resonance imaging (Magnetic Resonance Imaging Guided Linear Accelerator, MRI-Linac) are available.

Such more modern equipment is not compatible with traditional immobilization and repositioning systems. The reasons for inapplicability of such solutions are various, among which: incompatibility with the presence of a static magnetic field; intolerable radiation attenuation profile; dimensions of the immobilization system, which must comply with those of the device shaped like a tunnel (bore) of the magnetic resonance imaging scanner (generally, about 70 cm in diameter); comfort of the patient in maintaining the treatment position for even long periods of time.

Currently, customized solutions are prepared to position each patient, generally produced by industries in the sector or handcrafted by health technicians from medical radiology. Such solutions comprise, for example, vacuum immobilizer cushions, wherein the coils required for the examination of magnetic resonance imaging (Magnetic Resonance Imaging, MRI) are integrated.

However, traditional type immobilization systems do not allow optimal patient immobilization in modern hybrid equipment, in the different treatment positions required.

Mainly, the aforementioned immobilization systems provide the positioning of a coil for receiving radio frequencies within the magnetic field directly under the patient’s skull, chest, abdomen or pelvis (depending on the anatomical area to be treated). The presence of the coil makes the patient’s accommodation uncomfortable, and by virtue of its presence it can lead to unpredictable instability in its positioning. Due to this, unwanted sliding and/or rotating movements of the patient are frequent, making it necessary to reposition the patient himself to allow the correct delivery of the radiation treatment.

In particular, the commercially available solutions are penalized especially in immobilization in the anatomical areas of the head-neck and thorax-abdomen.

In the head and neck area, the main drawback in such situation consists in the use of thermoplastic masks which reduce the patient’s stability during the treatment of specific volumes of the head and neck, because of an immobilization of the patient only up to the chin. In addition, they maintain the patient still in a position not very comfortable, the patient resulting to be resting directly on the rear coil by shoulders and back. Furthermore, the current systems available do not allow the shoulders to be completely immobilized, as instead is the case of traditional radiotherapy.

In the thorax-abdomen area, the main drawback of current solutions is represented by the need to lay the patient directly on the rear coil, reducing his comfort and, above all, the reproducibility of the treatment, and limiting the usability of the individual patient’s set-up configurations.

Summary

The technical problem posed and solved by the present utility model is therefore to provide a system which allows to overcome the drawbacks above mentioned with reference to the known art.

The above problem is solved by a positioning system according to claim 1 .

Preferred features of the present utility model are the subject of the dependent claims.

The proposed positioning system is a modular type, configured to comfortably and effectively immobilize the patient during treatments delivered by linear accelerators with rear coil magnetic resonance imaging not integrated into the treatment bed.

The system according to this model substantially includes a main body having a support rigid surface, arranged at the top during use, with a flat and regular extension. Such support surface is designed to accommodate and immobilize the patient’s body on the bed of the hybrid linear accelerator.

The main body further bears at least one interspace, or pocket, which during use is arranged below the support surface, configured to contain one or more coils. The coils are suitable for receiving radio frequencies to perform resonance.

During use, the proposed positioning system is arranged such that the interspace develops mainly in a direction parallel to the major axis of the linear accelerator’s bed, in other words parallel to the direction of sliding of the bed itself within the linear accelerator.

The interspace allows the coil to be housed under the patient’s body, when the patient is stretched on the positioning system, on the linear accelerator’s bed. Thanks to the presence of the interspace for housing the coil, the patient, or any additional immobilization and repositioning systems (such as for example vacuum immobilizer cushions) interposed between the same and the upper surface of the proposed system, rest on a surface of rigid and regular support, and not directly onto the coil. Therefore, the proposed solution allows to reduce sources of error relating to the instability of patient positioning.

Thanks to its configuration, the system according to the present model allows to deliver therapies to the patient in a reproducible way, for an indefinite number of times.

Advantageously, the invention offers a solution which is also more comfortable for the patient with respect to the known art systems, while ensuring optimal image quality.

The proposed system can comprise three different conformations of modules for immobilizing and repositioning the different anatomical areas: head-neck, thorax, abdomen and pelvis.

Furthermore, the positioning system is compliant with the use of long thermoplastic masks, which further allow the patient’s shoulders to be immobilized (as shown in Figures 10 and 1 1 ).

Other advantages, characteristics and methods of use of the present utility model will become apparent from the following detailed description of several forms of implementation, presented by way of non-limiting examples.

Brief description of the figures

Reference will be made to the Figures of the attached drawings, wherein:

- Figures 1 and 2 respectively show a side perspective view and a top view of a preferred form of implementation of a module for the support of the pelvic anatomical area according to this utility model;

- Figures 3 and 4 respectively show a side perspective view and a top view of a preferred form of implementation of a module for the support of the head-neck and thorax/abdomen anatomical areas according to this utility model;

- Figures 5 and 6 respectively show a side perspective view and a top view of a preferred form of implementation of a module for the support of the thorax-abdomen-pelvis anatomical areas according to this utility model;

- Figure 7 shows a side perspective view of a preferred form of implementation of a positioning system according to the present utility model, configured to allow magnetic resonance imaging on the head-neck anatomical area;

- Figure 8 shows a side perspective view of a preferred form of implementation of a positioning system according to the present utility model, configured to allow magnetic resonance imaging on the whole patient’s body (total body);

- Figure 9 shows a side perspective view of a preferred form of implementation of a positioning system according to the present utility model, configured to allow magnetic resonance imaging on the whole patient’s body (total body) and having a grip element for the patient’s hands;

- Figures 10 and 11 respectively show a top view and a side perspective view of a preferred form of implementation of a positioning system according to the present utility model, in a therapy set-up with a long thermoplastic mask and coil;

- Figure 12 shows a top view of a preferred form of implementation of a positioning system according to this utility model, in a treatment set-up of the head-neck anatomical area with coil.

The aforementioned attached Figures are to be considered merely byway of nonlimiting examples. Detailed description of preferred forms of implementation of the model

This utility model relates to a positioning system configured to house at least one anatomical area of the patient when the latter is introduced into a linear accelerator with magnetic resonance imaging for the delivery of radiotherapy treatments. In order for the accelerator to further process a patient’s magnetic resonance imaging, it is equipped with at least one coil for radio frequency reception. In order to benefit the therapy, the patient is to be positioned in supine position within such type of accelerator, which has a tubular cavity or treatment tunnel as evident, for example, in Figure 12.

With reference to the preferred form of implementation shown in Figures 1 and 2, the positioning system 10 comprises at least one module 1 for housing a patient’s anatomical area. In the example of Figures 1 and 2, the module 1 is configured in particular for housing the patient’s pelvis, and can therefore be defined as a caudal module.

The module 1 is substantially plate-like conformed, in other words it has a predominant development in accordance with a longitudinal direction L and a transversal direction T, while the development is very small at the sagittal direction H. In this regard, the development of module 1 in the sagittal direction H can be referred as a thickness.

The plate-like body of module 1 has a first surface 2 suitable for supporting the patient’s anatomical area, and a second surface 3 opposite the first one 2. During use, the first surface 2 can be identified as a superior surface, while the second surface 3 can be identified as a bottom surface of module 1 .

During use, the first surface 2 is the one whereon the patient’s body is placed. This surface is preferably rigid and regular, to ensure a stable support for the patient. Module 1 , as well as the others, can be made in materials compatible with magnetic resonance imaging, with advantageous physical properties (e.g. dose absorption), resistant to the stresses resulting from the positioning and weight of the patient and easily sanitized, such as fiberglass.

Preferably, the first surface 2 of module 1 is substantially planar and extends according to a support plane S. The second surface 3 is further preferably substantially planar, and extended in accordance with a mounting plane P. According to preferred execution, the mounting plane P is parallel to said support plane S.

In particular, the longitudinal direction L is a direction of main development of module 1 which, during use, coincides with a direction of main development of the linear accelerator with magnetic resonance imaging 100, and also with the patient’s direction of movement to enter/exit the device 100.

Module 1 further has an interspace or pocket 4 interposed between the first and second surface 2, 3, configured to accommodate at least partially an element of coil 1 1 of the linear accelerator with magnetic resonance imaging 100 (Figures 10-12). When the coil 1 1 is housed in the pocket 4, it is located in proximity of, or rather below, the patient’s anatomical area subject to magnetic resonance imaging and radiotherapy, ensuring the correct outcome of the treatment, without however being in contact with the patient’s body and being therefrom deformed. Therefore, thanks to the presence of the pocket 4, the total absence of electrical components (wires and plates of the coil 1 1 ) in contact with the patient can be realized, allowing a comfortable, stable and reproducible positioning thereof. In other words, the positioning system makes the coil 1 1 retractable, without affecting the quality of the provided treatment.

Preferably, the pocket 4 has a mainly two-dimensional development, in other words it has a predominant development according to a longitudinal direction L and a transversal direction T, while the development is very small at the sagittal direction H.

According to preferred forms of implementation, the pocket 4 is bounded by at least a planar internal surface 40, which extends in accordance with a parallel plane with respect to the support plane S or the mounting plane P. Even further preferably, the internal surface 40 is the major surface of the pocket 4.

Preferably, a free first terminal end, or caudal end, 8 of the module 1 has two notches or lateral slits 9, which develop in accordance with the longitudinal direction L. Preferably, the notches 9 are made at the first surface 2, and at least one thereof does not pass through the entire thickness of module 1 . The notches 9 are configured to house the wires of the coil 11 from magnetic resonance imaging, which coil 11 is housed in the pocket 4 of the module itself.

With reference to Figures 3 and 4, a particular form of implementation of a cranial positioning module is shown, denoted by the numerical reference 20.

Such variant has the same technical characteristics already described with reference to module 1 , unless otherwise indicated.

In comparison to module 1 , module 20 has a free first terminal end, or cranial end 5, arranged along the longitudinal direction L, which has a conformation apt to define, in plan view, the profile of at least one support element, protruding with respect to the main body 24 of the module 20 according to the longitudinal direction L. In particular, the module 20 comprises three support elements 21 , 22, 23 protruding with respect to the main body 24 according to the longitudinal direction L.

A first support element 22, arranged centrally with respect to the other support elements 21 and 23, has a semi-circular geometry, which reproduces the size of the patient’s head: the module 20 is used for the support and treatment of the cranial anatomical area, in particular of the patient’s head. For this purpose, preferably the module 20 bears a pocket or interspace for housing the coil at the first terminal end 5, or better at the support element 22.

In particular, a notch 25 is obtained at a central portion of the support element 22 in order to house the coil 1 1 .

The additional support elements 21 and 23 are arranged laterally with respect to the central support element 22, and are preferably identical to each other and arranged in a specular manner with respect to the longitudinal direction L.

Preferably, each of the further support elements 21 and 23 has, at its own free terminal end, several notches or slits 26 configured to house the wires of the coil 1 1 for magnetic resonance imaging. The notches 26 are arranged at an internal lateral portion of the support elements 21 and 23, that is a portion facing the support element 22. Preferably, the notches 26 are realized at the first surface 2, and do not pass through the whole thickness of module 20. The extension of the notches 26 is in accordance with a direction oblique with respect to the longitudinal direction L, in particular a direction inclined at 45° with respect to the longitudinal direction L, and such that the extensions of the notches 26 encounter in a point inscribed within the surface 2 of module 20.

Furthermore, the module 20 can bear, on portions of the first surface 2, one or more holes in order to house rivets for fixing a thermoplastic mask, the same having length up to the shoulders or up to the chin. The holes are preferably arranged to define the profile of a shape of the patient’s skull and shoulders.

It should be noted that a feature of considerable importance for the purposes of compatibility with the thermoplastic masks made by the various manufacturers is the possibility of making the holes for the rivets according to predetermined patterns, which reproduce the geometries of the various models of masks available on the market. Figures 10 to 12 show a prototype of positioning system 1 according to the present model, comprising a caudal module 1 and a cranial module 20.

With reference to Figures 5 and 6, a further form of implementation of a further cranial positioning module is shown, denoted by the numerical reference 30.

Such variant has the same technical characteristics already described with reference to module 1 , although preferably having a larger dimension with respect to that of module 1 , since being intended to support the entire upper portion of the patient’s body (head, neck, thorax, abdomen and pelvis). Furthermore, according to a preferred variant, the module 30 has a free first terminal end 5, arranged along the longitudinal direction L, which has a smaller transverse dimension, in plan view, with respect to the rest of module 30, and is preferably square-plan.

Such free first terminal end 5 can be configured to house immobilization systems for the thorax and/or upper abdomen and/or pelvis or other customizable accessories, such as handlebars, handles or leg supports. In particular, with reference to the variant 30’ of Figure 9, the end 5 bears, at the first surface 2, a handle 7 configured to be grasped by the patient.

The modules 1 , 20, 30, 30’ preferably have an overall rectangular conformation in plan view, at less there are any protruding elements according to the longitudinal direction L. More in general, modules 1 , 20, 30, 30’ extend in accordance with a longitudinal direction L of main development, which represent the orientation direction of the modules themselves within the linear accelerator 100, during use.

According to preferred variants of this model, modules 1 , 20, 30, 30’ have a substantially symmetric conformation, in plan view, with respect to the longitudinal direction L.

In order to realize a support and positioning system for the entire patient’s body, it is necessary to couple the modules above described therebetween, in particular it is necessary to mechanically connect at least two modules (the caudal module and one of the cranial modules), to realize a single support surface 2 for the entire patient’s body.

For this purpose, preferably, each of the modules 1 , 20, 30 and 30’ above described has a second terminal end 6, arranged along the longitudinal direction L in the opposite position with respect to the first free terminal end 5, 8, shaped in such a way as to realize a temporary mechanical, in particular jointly, connection with a respective second terminal end 6 of another module.

The configuration of the modules and the joints is such that the positioning systems 10, 10’ and 10” resulting from the mechanical coupling have a continuous surface 2, outcome of the continuity between the surfaces 2 of the connected modules. Thereby, a stable patient positioning is assured.

In particular, the proposed positioning system may comprise at least two modules 1 , 20 (variant 10 of Figure 7, complete system in ‘head-neck’ set-up), or 1 , 30 (variant 10’ of Figure 8, system in simple ‘body’ set-up), or two modules 1 , 30’ (variant 10” of Figure 9, system in ‘body’ set-up with support for hands).

The configuration of modules 1 , 20, 30 and 30’ may be such that each bears a portion of the internal surface T of pocket 4, so that pocket 4 is completely obtained when the mechanical connection between the modules themselves is realized.

The present utility model has been hitherto described with reference to preferred forms of implementation. It should be understood that there may be other forms of implementation belonging to the same inventive core, as defined by the scope of the claims set forth below.