JP7545704B2 - Fixing device for suction type deformation mat - Google Patents

Description

The present invention relates to a fixing device for a suction-type deformable mat that is used primarily to suppress the patient's body movements during radiation therapy.

Radiation therapy is a treatment in which radiation is irradiated from outside the patient's body to damage cells in the affected area. Since radiation therapy is usually performed multiple times, it is extremely important not only to prevent the irradiation location from moving, but also to ensure that the patient's posture is reproducible, as the same location is irradiated each time. For this reason, body immobilization devices are used to restrict the patient's position on the treatment table and the patient's body movements during treatment.

For example, a rectangular carbon or wooden base plate that can be fixed onto a treatment table with side plates attached to the left and right sides is used.

Patent Document 1 also discloses a body fixation device that has a rectangular base plate made of reinforced cardboard, and has a structure in which the left and right panels on both sides of a rectangular recess in the surface of the base plate placed on a radiation treatment table are raised, and a rectangular insert plate made of reinforced cardboard is inserted between them.

Here, it is described that the suction-type deformable mat is fitted into the recess created in the gap between the rectangular recess of the base plate and the fitted plate, and the air is removed from the mat while it is in close contact with the patient, so that the front side takes on the shape of the patient, and the back side takes on a convex shape that corresponds to the rectangular recess of the base plate.

The base plate and the suction-type deformation mat are always fixed in the same position by fitting the concave part on the base plate with the convex part on the suction-type deformation mat.

JP 2011-115419 A

The suction-type deformation mat is an essential tool for radiation therapy because it can quickly form a concave shape that matches the patient's body shape and maintain that shape for a long period of time. To fix the suction-type deformation mat in a specific location on the treatment table, a fixing device is used to fix it to the treatment table.

Conventional wooden fixation devices were made by combining relatively thick pieces of wood to ensure strength. However, wooden fixation devices were heavy and inconvenient to use. In addition, because the structure was basically frame-shaped to ensure overall strength, when attempting to apply radiation to the affected area from all angles, there were angles where the radiation would not reach the affected area unless it passed through the fixation device.

In addition, although wood is a material that absorbs a small amount of radiation, it does have an effect on the radiation that is irradiated, so it was not in a desirable state.

As in Patent Document 1, when a recess is provided in the treatment table (base plate) and the suction-type deformable mat is deformed into a convex shape to fit into the recess, it appears at first glance that the suction-type deformable mat and the treatment table are fixed together. However, it is not easy to deform the suction-type deformable mat into a downward convex shape.

In addition, the suction-type deformable mat's volume shrinks and its shape is fixed when the air inside is removed. Therefore, the convex shape of the suction-type deformable mat will shrink when the air inside is removed, creating a gap between it and the concave shape in the treatment table. As a result, there is a play between the suction-type deformable mat and the treatment table, which reduces the reproducibility of the position.

The present invention was conceived in consideration of the above problems, and provides a fixing device for a suction-type deformable mat that fits snugly between the treatment table and the suction-type deformable mat, allowing radiation to be irradiated from any angle.

More specifically, the fixing device for the suction type deformable mat according to the present invention is
A substantially U-shaped base plate having a pair of horizontal plate portions parallel to each other and a vertical plate portion perpendicular to the horizontal plate portions, the maximum surface of the horizontal plate portions being flush with the maximum surface of the vertical plate portions ;
The vertical plate-shaped portion has a first standing wall provided on an end side opposite to the horizontal plate-shaped portion.

When the horizontal plate-shaped portion of the fixing device for the suction-type deformable mat according to the present invention is placed and fixed along the treatment table, the first standing wall is positioned so as to cross the suction-type deformable mat placed on top of it. When the suction-type deformable mat is placed on the fixing device, the first standing wall bites into the suction-type deformable mat. When the air is released from inside the suction-type deformable mat, the suction-type deformable mat contracts so as to sandwich the first standing wall. As a result, there is almost no gap between the first standing wall and the suction-type deformable mat, and the suction-type deformable mat can maintain a strong fixed state to the treatment table.

In other words, because the fixing device is sandwiched between the suction-type deformable mat, the position of the suction-type deformable mat can be fixed with high precision, and it can also be reproduced with high precision.

1A to 1C are diagrams showing a usage mode of the fixing device according to the present invention. FIG. 1 is a diagram showing the appearance of a fixing device according to the present invention. FIG. 4 is a front view of the first standing wall as seen from the closed side. 13 is a conceptual diagram showing how a suction-type fixing mat is fixed to a fixing device constituted by a base plate and a first standing wall. FIG. 11 is a conceptual diagram showing how a suction-type fixing mat is fixed to a fixing device composed of a base plate, a first standing wall, and a second standing wall. FIG.

The following is an explanation of the fastener for the suction-type deformable mat of the present invention, with reference to the drawings. Note that the following explanation illustrates one embodiment of the present invention and one example, and the present invention is not limited to the following explanation. The following explanation can be modified without departing from the spirit of the present invention.

Figure 1 shows how the fixing device 1 of the suction-type deformable mat of the present invention is used. Figure 1(a) shows the placement order of the treatment table 50, the fixing device 1 of the suction-type deformable mat (hereinafter simply referred to as "fixing device 1"), the patient 52, and the heat-deformable fixing belt 54. Figure 1(b) shows how they are actually used. The patient 52 is fixed to the treatment table 50 with both hands raised. Radiation R is irradiated from various angles between the fixing device 1 and the heat-deformable fixing belt 54.

The fixture 1 is fixed onto the treatment table 50. In FIG. 1, two fixtures 1 are fixed to the treatment table 50 facing each other, but only one may be used. A suction-type deformable mat 40 is placed on the fixture 1.

The suction-type deformable mat 40 is a mat in which microbeads such as styrene are filled into an airtight bag and suction ports 40L are provided to keep the mat airtight. When there is air inside the suction-type deformable mat 40, the mat changes shape like a normal bead cushion. After changing its shape, when the air inside is released, the bag tightens the microbeads to fit the deformed shape, and the mat solidifies in that shape.

In the first treatment, the patient 52 adjusts his/her posture on the suction-type deformation mat 40, and the irradiation position and angle are confirmed. After that, the air inside the suction-type deformation mat 40 is removed and the mat is solidified in a shape that maintains the posture of the patient 52. It is then fixed in place with a heat-deformable fixation band 54 (Figure 1 (b)).

The heat-deformable fixation band 54 is a thermoplastic film or net-like band that is heated to soften it and then fixed to the fixation device 1 together with the patient 52, who is resting on the suction-type deformable mat 40. When the temperature drops, it maintains its shape.

The suction-type deformable mat 40 and the heat-deformable fixation band 54 are stored as is and used for each treatment. In other words, the solidified suction-type deformable mat 40 and the heat-deformable fixation band 54 are made for each patient 52.

In the second and subsequent treatments, the patient 52 is held on the suction-type deformation mat 40, which maintains his or her posture, recreating the same posture as in the first treatment.

Fig. 2(a) shows a perspective view of the fixture 1 according to the present invention. Fig. 2(b) shows a plan view of the fixture 1. The fixture 1 according to the present invention is composed of a substantially U-shaped base plate 10 and a first standing wall 12. It may further have a second standing wall 14, a third standing wall 16, and a fourth standing wall 18.

The base plate 10 is composed of three members: a pair of horizontal plate-shaped parts 10a, 10b that are parallel to each other, and a vertical plate-shaped part 10c that is perpendicular to the horizontal plate-shaped parts 10a, 10b, and is roughly U-shaped in a plan view. For the sake of explanation, the side without the vertical plate-shaped part 10c is called the open side A of the fixture 1, and the side with the vertical plate-shaped part 10c is called the closed side B.

Each member has a certain width. The width of the horizontal plate-shaped parts 10a and 10b is horizontal plate-shaped part width 11a, and the width of the vertical plate-shaped part 10c is vertical plate-shaped part width 11c. The horizontal plate-shaped parts 10a and 10b may be provided with a through hole 10h for fixing the fixing device 1 to the treatment table 50.

The horizontal plate-shaped parts 10a and 10b of the base plate 10 are fixed to the treatment table 50, so that the stress applied in the front-rear direction (from the open side A to the closed side B, or the reverse direction) from the suction-type deformation mat 40 is received by the vertical plate-shaped part 10c. Here, if the vertical plate-shaped part 10c bends in the front-rear direction, the reproducibility of the position of the affected area decreases. Therefore, in order to make it difficult for the vertical plate-shaped part 10c to bend in a direction parallel to the horizontal plate-shaped parts 10a and 10b, a reinforcing part 10d may be provided between the horizontal plate-shaped parts 10a and 10b of the base plate 10 and the vertical plate-shaped part 10c.

The reinforcing portions 10d are provided at the corners of the joints between the horizontal plate portions 10a, 10b and the vertical plate portion 10c. It can be said that the reinforcing portions 10d are formed by extending the base plate 10 from the joints between the horizontal plate portions 10a, 10b and the vertical plate portion 10c in the direction of the vertical plate portion 10c and in the direction of the horizontal plate portions 10a, 10b.

A first standing wall 12 is formed on the vertical plate-shaped portion 10c of the base plate 10. The first standing wall 12 may be formed anywhere on the vertical plate-shaped portion 10c, but may be formed on the side opposite to the side where the horizontal plate-shaped portions 10a and 10b are joined, along the end edge 10ca of the vertical plate-shaped portion 10c. The first standing wall 12 may be formed along the entire length of the vertical plate-shaped portion 10c. However, it does not have to be along the entire length. Specifically, the patient 52 is held between the third standing wall 16 and the fourth standing wall 18. Therefore, it is desirable to provide the first standing wall 12 between the third standing wall 16 and the fourth standing wall 18. This is because the patient 52 is placed between them.

Refer to Figure 3. Figure 3(a) is a front view of the first standing wall 12 as viewed from the closed side B. The bottom side of the drawing is the base plate 10 side. The upper end 12a of the first standing wall 12 may be provided with a curved shape 20. In Figure 3(a), one concave curved shape 20b is provided between two convex curved shapes 20a. By providing the curved shape 20, the first standing wall 12 can easily bite into the suction-type deformable mat 40.

In addition, both ends 12aa, 12ab of the upper end 12a of the first standing wall 12 are chamfered to form a rounded surface. This is to prevent the suction-type deformable mat 40 from being scratched when the first standing wall 12 bites into the suction-type deformable mat 40.

It is preferable that the curved shape 20 on the upper end 12a be one or more of a convex curved shape 20a and a concave curved shape 20b. Specific examples are shown in Figures 3(b) and 3(c). Figure 3(b) shows a case where one convex curved shape 20a is applied to the upper end 12a, and Figure 3(c) shows a case where one concave curved shape 20b is applied to the upper end 12a. Both ends 12aa, 12ab are chamfered to have a rounded surface.

Note that the fixing device 1 of the present invention does not exclude cases where the curved shape 20 and rounded chamfering are not provided.

Referring again to FIG. 2, the vertical plate portion 10c may be provided with a second standing wall 14 facing the first standing wall 12. The second standing wall 14 may be provided between the third standing wall 16 and the fourth standing wall 18. The distance M between the second standing wall 14 and the first standing wall 12 is not particularly limited, but it is preferable to provide them at a distance of 20 mm or more. This is because the suction-type deformable mat 40 can easily enter between the first standing wall 12 and the second standing wall 14.

In FIG. 2, the second standing wall 14 is shown provided on the edge 10cb of the vertical plate-shaped portion 10c of the base plate 10 on the opposite side (opening side A) of the edge 10ca on which the first standing wall 12 is formed. In this way, providing the first standing wall 12 and the second standing wall 14 on both end pieces 10ca, 10cb of the vertical plate-shaped portion 10c also contributes to improving the rigidity of the vertical plate-shaped portion 10c.

Figure 4 shows a conceptual diagram of how the suction-type deformable mat 40 changes when only the first standing wall 12 is present. The base plate 10 of the fixture 1, the first standing wall 12, and the suction-type deformable mat 40 are depicted.

Figure 4 (a) shows a cross-sectional view of the first standing wall 12 of the fixture 1. The cross-section is taken along line C-C in Figure 2 (b), and shows the fixture 1 fixed onto the treatment table 50 with the suction-type deformable mat 40 placed on top of it. This figure also shows the case where the second standing wall 14 is not present.

When the suction-type deformable mat 40 is placed on the fixture 1, the suction-type deformable mat 40 deforms according to the shape of the fixture 1 (the shape of the first standing wall 12). However, the surface of the suction-type deformable mat 40 does not completely conform to the first standing wall 12, and a gap 26 is generated between the suction-type deformable mat 40 and the first standing wall 12. When the air inside the suction-type deformable mat 40 is released, the suction-type deformable mat 40 contracts in the direction of the arrow 40d, and the gap 26 becomes smaller and becomes a gap 27 (see FIG. 3(b)).

When the suction-type deformable mat 40 is removed from the fixture 1 in this state, a recess 40a corresponding to the first standing wall 12 is formed. This recess 40a is formed narrow because it is formed to bite into the first standing wall 12. Therefore, when the suction-type deformable mat 40 is placed on the fixture 1 again, the gap between the recess 40a and the first standing wall 12 is very narrow, and they can be fitted together with so-called little backlash. As a result, the accuracy of reproducibility of the position of the suction-type deformable mat 40 can be increased.

Figure 5 shows how the suction-type deformable mat 40 changes when a first standing wall 12 and a second standing wall 14 are present. The cross section is the same as in Figure 4. Referring to Figure 5(a), when the suction-type deformable mat 40 is placed on the fixture 1, a gap 26 is created between the suction-type deformable mat 40 and the fixture 1, as in the case of Figure 4. In particular, a relatively large gap 26a is created between the first standing wall 12 and the second standing wall 14.

Next, when the air is released from the suction-type deformable mat 40, the surface of the suction-type deformable mat 40 appears to shrink, so that the outer side 12b of the first standing wall 12 and the outer side 14b of the second standing wall 14 move in the direction of the arrow 40d, and the gap 26 between the suction-type deformable mat 40 becomes smaller. Note that the outer side 12b of the first standing wall 12 and the outer side 14b of the second standing wall 14 refer to the opposite sides of the respective standing walls when the side where the first standing wall 12 and the second standing wall 14 face each other is viewed as the inside.

On the other hand, in the gap 26a, the surface of the suction-type deformable mat 40 is pulled in the direction of the arrow 40f, and the gap 26a deforms to become larger (see Figure 4(b)).

When the solidified suction-type deformable mat 40 is removed from the fixture 1 in this state, a recess 40b is formed in the suction-type deformable mat 40 (see FIG. 4(c)). This recess 40b is the result of the first standing wall 12 and the second standing wall 14 pulling on each other on the surface of the suction-type deformable mat 40, and the portions 41a and 41b where the first standing wall 12 and the second standing wall 14 were abutting have solidified with great precision.

Therefore, if a suction-type deformable mat 40 having such a recess 40b is placed on the fixing device 1, it can be fixed in the same position with almost no wobble. As a result, the accuracy of reproducibility of the position of the suction-type deformable mat 40 can be improved.

Refer to FIG. 2 again. The horizontal plate-shaped portions 10a and 10b may be provided with a third standing wall 16 and a fourth standing wall 18, respectively. These standing walls are used to fix the heat-deformable solid band 54 that is used to further fix the patient 52 after the patient 52 is placed on the suction-type deformable mat 40 fixed to the treatment table 50. In other words, the third standing wall 16 and the fourth standing wall 18 hardly bite into the suction-type fixing mat 40. However, when these standing walls are formed, the rigidity of the horizontal plate-shaped portions 10a and 10b is increased.

The base plate 10 and the first standing wall 12, second standing wall 14, third standing wall 16, and fourth standing wall 18 are preferably made of a low radiation absorbing material. The fixing device 1 is used to fix the patient during radiation therapy, and in radiation therapy, it is desired to irradiate the affected area with radiation from all directions. In this case, it is most desirable for the fixing device 1 not to be in the line of radiation to be irradiated. However, even if the fixing device 1 is in the line of radiation to be irradiated, if it is made of a low radiation absorbing material, it will have little effect on the irradiated radiation.

Possible low radiation absorbing materials include foamed resin and FRP (Fiber-Reinforced Plastics).

Of the components that make up the fixture 1, it is desirable that at least the base plate 10 and the first and second standing walls 12 and 14 are made integrally. The components that make up the fixture 1 are subjected to large stresses when fixing the patient 52, so it is preferable that they are made integrally rather than made by joining separate components. Here, "integrally" refers to a state in which each component is molded continuously and multiple components are not joined together with adhesive materials such as glue or screws/bolts.

The third standing wall 16 and the fourth standing wall 18 are provided along the inside of the horizontal plate-like portions 10a and 10b. They may be provided directly on the base plate 10. Alternatively, an L-shaped cross-section member may be joined to the horizontal plate-like portions 10a and 10b. It is preferable that the third standing wall 16 and the fourth standing wall 18 have through holes for fixing the heat-deformable solid band 54.

Next, the manner in which the fixing device 1 according to the present invention is used will be described. Referring to FIG. 1, a pair of fixing devices 1 are fixed to a treatment table with their first standing walls 12 facing each other at a certain distance. A suction-type deformable mat 40 is placed so as to cover the second standing walls 14 of the pair of fixing devices 1. Then, a patient 52 is placed on the suction-type deformable mat 40. After the suction-type deformable mat 40 has been adjusted to fit the patient 52 and the pair of fixing devices 1, the air in the suction-type deformable mat 40 is deflated.

The front side of the suction-type deformable mat 40 hardens according to the shape of the torso of the patient 52, and the back side bites into the fixing device 1. The back side of the suction-type deformable mat 40 is fixed by biting into the fixing device 1 as shown in Figure 4 or Figure 5. The patient 52 is then further fixed with a heat-deformable fixing belt 54.

The first standing walls 12 of the fixture 1 face each other and are spaced a distance L apart. Therefore, no part of the fixture 1 is located between the distance L. If the patient's trunk is positioned between the distance L, the fixture 1 will not interfere with radiation no matter what direction it is irradiated from.

In addition, if the suction-type deformable mat 40 is stored after the radiation treatment is completed, the patient 52 can be fixed again at a later date in the same position and in the same posture on the treatment table 50. At this time, the back surface of the suction-type deformable mat 40 fits snugly into the fixing device 1, so the patient can be fixed with almost no error.

As described above, by using the fixing device 1 of the present invention, the suction-type deformable mat 40 can be repeatedly fixed in the same position on the treatment table 50 without any rattling.

The present invention can be used not only during radiation therapy, but also during X-ray imaging of specific tissues and diagnostic tests such as MRI and RI.

1 Fixing device 10 Base plate 10a, 10b Horizontal plate-shaped portion 10c Vertical plate-shaped portion 10d Reinforcement portion 10ca End edge 10cb End edge 11a Horizontal plate-shaped portion width 11c Vertical plate-shaped portion width 12 First standing wall 12aa, 12ab Both ends 12a Upper end 12b Outer side 14 Second standing wall 14b Outer side 16 Third standing wall 18 Fourth standing wall 20 Curved shape 20a Convex curved shape 20b Concave curved shape 26, 27 Gap 40 Suction type deformable mat 40d Arrow 40a Depression 40L Suction port 40L Treatment table 52 Patient 54 Heat deformable fixing band

Claims (6)

A substantially U-shaped base plate having a pair of horizontal plate portions parallel to each other and a vertical plate portion perpendicular to the horizontal plate portions, the maximum surface of the horizontal plate portions being flush with the maximum surface of the vertical plate portions ;
A fixing device for a suction-type deformable mat, characterized in that it has a first standing wall provided on the end side of the vertical plate portion opposite to the horizontal plate portion. The fixing device for a suction-type deformable mat described in claim 1, characterized in that the first standing wall is wavy with one or more curved portions. The fixing device for the suction-type deformable mat described in claim 1 or 2 further comprises a second standing wall provided on the vertical plate portion, facing the first standing wall. 4. The fixture for a suction-type deformable mat according to claim 3, wherein the height of the second wall is lower than the height of the first wall. 5. The fixing device for a suction-type deformable mat according to claim 3, wherein the second standing wall is shorter than the first standing wall. The fixing device for a suction-type deformable mat described in any one of claims 1 to 5, further comprising third and fourth standing walls provided along the horizontal plate-shaped portion.