Device For Immobilizing The Head Of A Patient

Abstract

The invention relates to a device for immobilizing the head of a patient in an installation for carrying out radiotherapy, wherein the device comprises a thermoplastic mask, shaped according to the contour of the patient's head, and a mouthpiece, wherein the mouthpiece has a central part from which a spout protrudes in the direction of the mouth and from which a holding structure protrudes in the direction away from the mouth, wherein an air channel is provided which extends through the mouthpiece from the mouth-side end of the spout to the side of the central part in the direction away from the mouth, and wherein a region of the mask is shaped according to the contour of the holding structure. The invention further relates to a method for producing such a device, to the use of such a device for immobilizing the head of a patient in an installation for carrying out radiotherapy, and to an installation for carrying out radiotherapy which, in order to immobilize the head of a patient, comprises such a device.

Claims

1. A device for immobilising the head of a patient in an installation for carrying out radiotherapy, wherein the device comprises a thermoplastic mask shaped according to the contour of the patient's head and a mouthpiece, wherein the mouthpiece has a central part from which a spout protrudes in the oral direction and from which a holding structure protrudes in the aboral direction, wherein an air channel is provided which passes through the mouthpiece from the mouth-side end of the spout to the aboral side of the central part, and in that a region of the mask is shaped according to the contour of the holding structure.

2. The device according to claim 1, wherein the mouthpiece is not connected to the mask and sits with its holding structure loosely in the corresponding shaping in the mask.

3. The device according to claim 1, wherein the holding structure has at least two structural elements protruding from the central part and/or in that one or more structural elements of the holding structure have an elongated shape in the contact plane of the mask.

4. The device according to claim 3, wherein the structural elements comprise a merlon protruding from the central part in the axis of the spout, wherein the air channel continues to the aboral end of this merlon.

5. The device according to claim 1, wherein an aperture is incorporated in the region of the mask that is shaped according to the contour of the holding structure.

6. The device according to claim 1, wherein the central part is a shield, which extends in a manner substantially normal to the spout.

7. The device according to claim 1, wherein accommodating recesses are provided opposite one another on the spout.

8. The device according to claim 1, wherein the air channel comprises a bore.

9. A method for producing a device according to claim 1, wherein a flat and not yet shaped thermoplastic mask is heated until the mask material is formable, in that the mask that has been thus heated is stretched over the head of a patient, who holds the spout of the mouthpiece in his mouth such that the holding structure is directed towards the mask material, and in that the mask is then secured to a holder that is in a fixed position relative to the patient until it sets by cooling.

10. A method for immobilising a head of a patient in an installation for carrying out radiotherapy, said method comprising immobilising said head with the device of claim 1.

11. A method for carrying out radiotherapy on a patient, said method comprising immobilising a head of said patient with the device of claim 1, and then conducting said radiotherapy on said patient.

12. The device according to claim 1, wherein accommodating recesses are provided opposite one another on the spout in the transition region between said spout and said shield.

13. The device according to claim 1, wherein the air channel comprises a bore, which runs substantially perpendicular to the contact plane of the mask.

Description

[0027] Further details and advantages of the invention can be taken from the following exemplary embodiment, which is explained below with reference to the figures. The figures show the following:

[0028] FIG. 1: a first embodiment of a mouthpiece of a device according to the invention;

[0029] FIG. 2: a second embodiment of a mouthpiece of a device according to the invention;

[0030] FIG. 3: views of a thermoplastic mask of a device according to the invention; and

[0031] FIG. 4: a third embodiment of a mouthpiece of a device according to the invention.

[0032] In FIG. 1, a mouthpiece 100 of an embodiment of a device according to the invention is shown in a perspective view. The mouthpiece is suitable in particular for use during irradiation of a brain tumour.

[0033] The mouthpiece 100 comprises a central shield 110, which lies substantially parallel to the patient's frontal plane when the device is in use. In the example shown, it has a circular basic shape with partially circular indentations being provided on both the left-hand and right-hand upper sides. Starting from this shield 110, a horizontally flattened spout 120 extends in the oral direction. The width of the spout 120 in the example shown corresponds approximately to the distance between the vertices of the indentations. The spout 120 is held in the mouth by the patient during use. The shield 110 acts as a limiter and defines the penetration depth of the spout 120 in the patient's mouth, wherein in particular too deep a penetration is to be avoided.

[0034] In the transition region between spout 120 and shield 110, accommodating recesses 115 for lips and teeth are provided opposite one another. Owing to its special fit, the mouthpiece 100 is also suitable for toothless patients.

[0035] On its aboral side, the shield 110 is provided with a holding structure 130. In the example shown, the holding structure 130 comprises two webs protruding vertically from the shield, which follow the edge profile of the indentations in the shield 110. The contour of this holding structure 130 is reproduced in the mask 200 (FIG. 3) of the device during use in order that an accurate and reproducible position of the mouthpiece 100 can be fixed in relation to the mask 200.

[0036] The mouthpiece 100 further comprises an air channel 140, which extends from the mouth-side end of the spout 120 to the aboral side of the shield 110 and thus passes through the mouthpiece 100 from the oral side to the aboral side. The air channel 140 enables the patient to breathe through the mouth despite having the spout 120 in his mouth and surrounding it with his lips. In the example shown, the air channel 140 comprises a single bore.

[0037] In FIG. 2, a mouthpiece 100 of a further embodiment of a device according to the invention is shown in a perspective view. The mouthpiece 100 of FIG. 2 is suitable in particular for use in the irradiation of an ENT tumour. Identical reference numerals are used for corresponding parts in FIG. 2. The mouthpiece 100 of FIG. 2 differs from the mouthpiece of FIG. 1 by the shape of the spout 120, which is more bulbous and approximately round in its cross-section. This alternative shape allows a specific positioning of the upper and lower jaw to be achieved and enables the tongue to be secured on the floor of the mouth.

[0038] In FIGS. 3a-3c, a mask 200 of an embodiment of a device according to the invention is shown from multiple perspectives. FIG. 3a shows the mask 200with reference to the patientat an angle from below, FIG. 3b at an angle from above and FIG. 3c at an angle from the right.

[0039] The mask 200 is represented by a leaf-like sheet of a thermoplastic polymer material, which has been shaped according to the contour of the patient's head. In the figures, inter alia, contours corresponding to the chin (reference numeral 201), nose (reference numeral 202), forehead (reference numeral 203) and cheeks (reference numeral 204) can be seen. The sheet is penetrated by closely spaced small holes, such that it has an almost net-like structure. This increases patient comfort and enables the patient to perceive his surroundings. Furthermore, the shaping of the originally flat sheet is facilitated by the holes. The sheet representing the mask 200 is mounted at the rear end, as can be partially seen in FIG. 3a, in a mask frame 300, which can be secured on a treatment table (not shown) of an installation for carrying out radiotherapy.

[0040] In the region of the sheet that covers the patient's mouth region, a mouthpiece contour 210 can be seen, which corresponds to the holding structure 130 of the mouthpiece 100 (FIG. 1 or 2). With the aid of this mouthpiece contour 210, an accurate and reproducible position of the mouthpiece 100 can be fixed in relation to the mask 200. In the example shown, the mouthpiece contour 210 has an X-like shape, which is obtained as a necessary consequence of the shape of the holding structure 130 of the mouthpiece 100. The four retention points at the corner edges here facilitate a non-rotatable fixing.

[0041] At a point of the mask 200 that lies directly over the patient's mouth during use, an aperture is incorporated. It therefore lies approximately in the centre of the mouthpiece contour 210. In the example shown, the aperture 220 is approximately circular. Thanks to the aperture 220, the air channel 140 of the mouthpiece 100 (FIG. 1 or 2) is unobstructed during use of the device and the patient's breathing is not impaired.

[0042] With the aid of the device shown, an immobilising of the head of a patient can take place in an installation for carrying out radiotherapy.

[0043] During the initial fitting, the patient first holds the spout 120 of the mouthpiece 100 in his mouth such that the recesses 115 are enclosed between teeth and lips. Next, as known in principle from the prior art, the mask 200 with heated mask material is stretched over the patient's head so that the contour of the patient's head is shaped in the originally flat mask material. In contrast to the prior art, however, not only is the contour of the patient's head reproduced in the mask material but additionally the holding structure 130 of the mouthpiece 100 as a mouthpiece contour 220. The mask material then hardens by cooling. Once the mask material has hardened, the mask 200 is taken off the patient and the mouthpiece 100 is removed from the patient. The aperture 220 is cut out afterwards. The mask 200 with the hardened mask material that has been shaped for the specific patient is stored for further immobilisations. The mouthpiece 100 may be either cleaned for reuse or disposed of.

[0044] In every further immobilising, e.g. in the context of diagnostic or therapeutic steps, the patient again holds the same or an identical mouthpiece 100 in his mouth and the mask 200 that has been kept since the initial fitting described above, with the hardened mask material that has been shaped for the specific patient, is reapplied.

[0045] With the aid of this novel system, high positioning accuracy of the mask 200 on the patient's head can be achieved and head movements and in particular jaw movements can be largely avoided. At the same time, the patient's breathing is scarcely impaired and patient comfort is improved compared to existing solutions.

[0046] Finally, FIGS. 4a-4e show a further embodiment of a mouthpiece 100 of a device according to the invention, and specifically in a perspective illustration (FIG. 4a), in side views (FIGS. 4b-c) and as top views from the oral side (FIG. 4d) and from the aboral side (FIG. 4e).

[0047] The mouthpiece 100 of the embodiment according to FIG. 4 is very similar to the mouthpiece of the embodiment according to FIG. 2 in principle. The only differentiating feature is the additional aboral holding structure in the form of a merlon 131, which protrudes vertically from the central part 110 in the axis of the spout and clearly projects beyond the webs 130 in the aboral direction. The air channel 140 in this embodiment continues to the aboral end of the merlon 131 and therefore does not already terminate on the aboral side of the shield 110.

[0048] By using the merlon 131, the securing of the mask 200 on the mouthpiece 100 can be improved. Furthermore, by raising the outlet opening of the air channel 140 from the shield 110, in the event of the patient's vomiting, the vomit is prevented from being able to pass back into the air channel 140. The merlon 131 can in some circumstances project at least partially through the aperture 220 when the mask 200 is applied; however, it is preferred for the mask material to be shaped such that the aperture 220 rests on the tip of the merlon 131.