IMMOBILISATION DEVICE FOR RADIOTHERAPY

Abstract

The invention describes an immobilisation device (1) for radiotherapy comprising: an inclined plate (2) for supporting the back of a patient, wherein said plate (2) is inclined in a longitudinal direction and has a lower end (21) and an upper end (2u); and a lower platform (3) for supporting the buttocks of the patient, wherein said lower platform (3) can be coupled to the lower end (21) of the inclined plate (2), wherein the lower platform (3) is rotatable to make it easier to place the patient on the device (1). The lower platform can also comprise a protuberance (4) for supporting the perineum of the patient and plates (5) for immobilising their hips.

Claims

1. An immobilisation device (1) for radiotherapy, comprising: an inclined plate (2) for supporting the back of a patient, wherein said plate (2) is inclined in a longitudinal direction and has a lower end (21) and an upper end (2u); and a lower platform (3) for supporting the buttocks of the patient, wherein said lower platform (3) is configured for being arranged adjacent to the lower end (2a) of the inclined plate (2), characterised in that the lower platform (3) is rotatable to make it easier to place the patient on the device (1).

2. The device (1) according to claim 1, wherein the lower platform (3) comprises a vertically projecting protuberance (4) which is transversely centred in relation to the inclined plate (2) when it is in a usage orientation, wherein the protuberance (4) is configured such that it can be introduced between the legs of the patient.

3. The device (1) according to claim 2, wherein the protuberance (4) has a cross-section with smooth curves that are devoid of sharp edges to prevent injuring the patient.

4. The device (1) according to claim 3, wherein the protuberance (4) has a cross-section with a circular, elliptical, or oval shape.

5. The device (1) according to any of claims 2 to 4, wherein the lower platform (3) further comprises in lateral areas according to the usage orientation a pair of vertically projecting plates (5) which are configured for compressing the hips of the patient.

6. The device (1) according to any of the preceding claims, wherein the inclined plate (2) is formed by two V-shaped side sub-plates (21, 22) which are additionally inclined in a transverse direction so as to prevent the patient from being able to turn.

7. The device (1) according to any of the preceding claims, wherein the inclined plate (2) further comprises two side contention walls (23, 24) projecting essentially in a vertical manner for closely housing the patient.

8. The device (1) according to any of the preceding claims, wherein the inclined plate (2) comprises a central longitudinal cavity (25) to make it easier to position the spinous process of the patient.

9. The device (1) according to any of the preceding claims, wherein the inclined plate (2) is configured such that its angle of inclination is fixed and cannot be modified.

10. The device (1) according to any of the preceding claims, wherein the inclined plate (2) comprises at its upper end (2u) arm restraining means (6) comprising a restraining element (61), wherein said restraining element (61) is movable between a retracted position located longitudinally above a supporting position (SP) for supporting the patient's head, and an extended position located longitudinally at the height of the supporting position (SP) for supporting the patient's head, and wherein in the extended position the lower end of the restraining element (61) is perpendicularly separated from the inclined plate (2) by a distance that is enough for accommodating the patient's head such that it is supported on said supporting position (SP).

11. The device (1) according to claim 10, wherein the distance between the inclined plate (2) and the lower end of the restraining element (61) when said restraining element (61) is in the extended position is between 20 cm and 30 cm.

12. The device (1) according to any of claims 10 to 11, wherein the restraining element (61) is sliding between the retracted position and the extended position.

13. The device (1) according to claim 12, wherein the arm restraining means (6) comprise a support (62) arranged at the upper end (2u) of the inclined plate projecting vertically above the plate to which there is coupled in a sliding manner in the longitudinal direction the restraining element (61).

14. The device (1) according to any of claims 10 to 13, wherein the restraining element (61) has arm fixing means (63) actively restraining the arms of the patient.

15. The device (1) according to claim 14, wherein the arm fixing means (63) comprise wrist straps (63) configured for immobilising the wrists of the patient.

16. The device (1) according to any of the preceding claims, further comprising graduated stereotactic marks (7) arranged on the outer face of the side contention walls (23, 24).

17. The device (1) according to any of the preceding claims, further comprising a stereotactic arch (8) that can be coupled to the inclined plate (2).

18. The device (1) according to any of claims 16 to 17, wherein the side contention walls (23, 24) and/or the stereotactic arch (8) have a series of holes which allow seeing the stereotactic marks.

19. The device (1) according to any of the preceding claims, further comprising first fixing means located in the inclined plate (2) for supporting the antenna of magnetic resonance equipment.

20. The device (1) according to any of the preceding claims, further comprising second fixing means located in the inclined plate (2) for a thermoplastic immobilisation blanket of the patient.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] FIG. 1 shows a perspective view of a first example of an immobilisation device according to the prior art.

[0050] FIG. 2 shows a perspective view of a second example of an immobilisation device according to the prior art.

[0051] FIG. 3 shows a perspective view of an immobilisation device according to the present invention.

[0052] FIGS. 4a, 4b, and 4c, respectively, show a perspective view, a profile view, and a plan view of a lower rotatable platform according to the present invention.

[0053] FIGS. 5a and 5b show respective side views of an inclined plate provided with arm restraining means according to the present invention (the lower rotatable platform is not shown for the sake of simplicity).

[0054] FIGS. 6a to 6f show different steps representative of a method of using the device according to the present invention.

PREFERRED EMBODIMENT OF THE INVENTION

[0055] FIG. 3 shows a general perspective view of the immobilisation device (1) according to the present invention. This device (1) is fundamentally formed by two elements: a lower platform (3) and an inclined plate (2). The longitudinal and transverse directions are depicted by means of respective lines referred to as (LD) and (TD), respectively.

[0056] In relation to the platforms used in the devices of the prior art shown in FIGS. 1 and 2, the lower platform (3) has the particularity that it is rotatable. Specifically, as can be seen in greater detail in FIGS. 4a to 4c, this platform (3) is formed by a base (31) which, in this example, has a square shape, although the base (31) can in principle have any shape as long as it provides a firm support for supporting the patient's weight. Specifically, the base (31) is rotatably coupled to a rotatable plate (32) on which the patient will sit. In this example, the rotatable plate (32) has a round shape, although this is also not essential, and the base may adopt other shapes, if necessary. The rotatable plate (32) is coupled to the base (31) through a rotary attachment (33). In terms of size, the rotatable plate (32) of the platform (3) will have a suitable size for a patient to sit thereon.

[0057] FIG. 3 also shows a protuberance (4) intended for being positioned between the legs of the patient, supported on their perineum to prevent them from sliding down according to the longitudinal direction of the inclined plate (2). This protuberance (4), which is shown in greater detail in FIGS. 4a to 4c, has a shape that is devoid of sharp edges to be comfortably supported on the inner thigh of the patient. Specifically, in this example it has a cylindrical shape with a semi-spherical upper end. The diameter of this protuberance (4) is configured so that it fits comfortably between the legs of the patient, and can be between 8 cm and 15 cm, for example. Its height will also be sufficient to prevent the patient from being able to slide over it, and can be between 10 cm and 20 cm, for example. With respect to its position, it is important to highlight that it is not essential for the protuberance to be arranged exactly in the centre of the rotatable plate (32). However, when the rotatable plate (32) is in the usage orientation, it is important for the protuberance (4) to be transversely centred and arranged at a certain distance from the edge of the base (31) which is coupled to the lower end (21) of the inclined plate which allows comfortably accommodating the buttocks of the patient.

[0058] FIG. 3 also shows a pair of parallel vertical plates (5) facing one another and located in the peripheral area of the circumference of the rotatable plate (32). These plates (5) are separated by an approximate distance of 40 cm for constraining the hips of the patient and preventing them from moving. The dimensions of the plates (5) are selected so that they constrain the hips of the patient without damaging them with their sharp edges, either the sharp side edges or the sharp upper edge. In this example, the plates (5) have a length of 10 cm and a height of 15 cm. Furthermore, it is not essential for the plates (5) to be flat, where they can have a small curvature towards the inside of the rotatable plate (32) to adapt to the hips of the patient in a more ergonomic manner. Moreover, with respect to their position, it is not strictly necessary for the plates to be arranged in diametrically opposing positions. It also not essential for both plates (5) to be aligned with the protuberance (4), as it can be slightly shifted in the direction perpendicular to said line joining the plates (5), where required, for maximum patient comfort.

[0059] The inclined plate (2) has an essentially rectangular shape and is arranged according to an inclination in a longitudinal direction coinciding with the direction of its long side. The short lower side, located at its lower end (21), is coupled to a side of the rotatable platform (3) through any means suitable to that end, such as press fit, tongue and groove joints, or others, for example. As discussed above, these coupling means can be of variable length. The short upper side, located at its upper end (2u), is supported on rigid legs which keep the angle of inclination fixed and unchanging at a value of about 10. An important particularity of the described inclined plate (2) is that the surface on which the patient resist is not strictly flat, but rather is formed by two V-shaped sub-plates (21, 22) having a small inclination towards the centre of the plate (2). Each of the sub-plates (21) can have an essentially elongated rectangular shape the ends of which are fixed to a respective supporting elements located at the lower and upper ends (21, 2u) of said plate (2). This inclination helps to immobilise the patient even more while using the device (1) of the invention.

[0060] The plate (2) furthermore has essentially vertical contention walls (23, 24) located along its side edges. In this example, there are two straight vertical walls (23, 24) that span both side edges of the plate (2) entirely and have an approximate height in relation to the surface of the plate (2) of about 9 cm. The patient is thus fitted between these two walls (23, 24) with hardly any margin for movement. The walls (23, 24) furthermore have on their outer face graduated stereotactic marks (7) which allow a precise positioning of the patient. They also have a series of openings and fixing elements intended for the coupling of various elements used during radiotherapy treatment, such as the antenna for magnetic resonance equipment, a thermoplastic immobilisation blanket, or the described stereotactic arch (8), for example.

[0061] FIG. 3 also shows how the plate (2) has a central longitudinal cavity (25) separating both sub-plates (21, 22). This central longitudinal cavity (25) is intended for housing the spinous process of the patient, which results not only in greater comfort but also in increased precision during positioning. In this example, the width of the central longitudinal cavity (25) is 6 cm.

[0062] The device (1) of the invention further comprises fixing means (6) for fixing the arms of the patient. These fixing means (6) comprise a restraining element (61) movable between a retracted position and an extended position to which the arms of the patient are fixed. In this example, the restraining element (61) adopts the shape of an essentially flat plate to which constraining means in the form of wrist straps (63) are fixed. These wrist straps (63) constitute a significant advantage in relation to the fixing elements used in the immobilisation devices known today, as they allow firmly constraining the wrists of the patient and the patient therefore does not have to make any effort to keep their arms still and away from the treatment area.

[0063] The fixing means (6) further comprise a supporting plate (62) located at the upper end (2u) of the plate. This supporting plate (62) has an opening through which a rod slides at the end of which there is arranged the fixing element (61). In that sense, as shown in FIG. 5a, when the fixing element (61) is in the retracted position, it is arranged adjacent to the supporting plate (62), in a position longitudinally above the supporting position (SP) for supporting the patient's head. In this supporting position (SP), a headrest of the type conventionally used in immobilisation devices of this type has been shown. Therefore, when the fixing element (61) is in the retracted position the patient can lean back normally until their head is placed in said supporting position (SP). FIG. 5b shows the fixing element (61) in an extended position. As can be seen, in the extended position the fixing element (61) is located according to the longitudinal direction at the height of the supporting position (SP) for supporting the patient's head. Furthermore, the lower end of the fixing element (61) is sufficiently separated from the inclined plate (2) so as to leave enough space for the patient's head. In this example, the distance is 26 cm. As a result of this configuration, in this device the arms of the patient are immobilised in a much more comfortable position than in earlier devices, for example approximately in front of their eyes or forehead.

[0064] FIGS. 6a to 6f show the different steps of a process of immobilising a patient using the device of the present invention. FIG. 6a shows the immobilisation device (1) of the invention placed on the stretcher of a linear accelerator. FIG. 6b shows a first step in which the patient has sat on the lower platform (3). To that end, the stretcher has previously moved down from its initial height and the rotatable plate (32) of the platform (3) has furthermore been placed in the initial orientation. In this example, the initial orientation corresponds to the one depicted in FIGS. 6a and 6b, in which the plates (5) are aligned according to the longitudinal direction. With this orientation of the rotatable plate (32), the patient only has to lower themselves until they are seated such that the protuberance (4) is arranged between their legs and their hips are fitted between the plates (5). Next, FIG. 6c shows the subsequent step in which the medical personnel turns the rotatable plate (32) 90 from its initial position to its usage position. In this example, the usage position is the one depicted from FIG. 6c onwards, in which the line joining the plates (5) is perpendicular to the longitudinal direction of the device (1). To enable performing this 90 turn of the rotatable plate (32) with the patient seated thereon, the legs of the patient are lifted. This results in the patient being aligned according to the longitudinal direction of the device. Next, as seen in FIG. 6d, the patient simply leans back until they rest on the inclined plate (2). The spinous process of the patient is aligned in the central longitudinal cavity (25), and the rest of the back is supported on the sub-plates (21, 22) inclined towards the central longitudinal line of the plate (2). The shoulders of the patient are fitted against the side contention walls (23, 24) of the inclined plate (2). Finally, at the end of this step the patient's entire trunk is constrained by the different elements of the inclined plate (2) and their pelvis and perineal area are also immobilised by the corresponding elements of the lower rotatable platform (3). FIG. 6e shows the subsequent step consisting of the immobilisation of the arms of the patient. To that end, the arm fixing element (61) slides from the retracted position shown in FIG. 6d to the extended position shown in FIG. 6e. The arms of the patient are fixed to the arm fixing element (61) by means of wrist straps (63). This results in the arms of the patient being fixed approximately in front of their eyes or forehead, and furthermore the patient can allow their arms to go limp such that they hang from the wrist straps, thereby avoiding the exertion of any effort will may tire the patient out. The patient is already completely immobilised and ready to start treatment. In a last step, FIG. 6f shows how the stereotactic arch (8) is fixed to the inclined plate (2).