JP2000287966A - Patient positioning device for medical apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a patient positioning device which simply and accurately accomplishes the adjusting of the position and angle of a projector irrespective of already adjusted parameters. SOLUTION: A projector 1 and a transparent block 9 are carried on a fixed frame 8. The projector 1 projects a cross-mark laser light as collimator light 11. The transparent block 9 herein used has both sides optically parallel with each other, made of a transparent and homogeneous material with a uniform refractive index and rotated about an axis 3 being held on a rotary frame 7. Moreover, it is rotated about an axis 2 being held on a rotary frame 6 to shift incident light horizontally and vertically and it parallel as output light thereby achieving a fine positional adjustment of an output collimator light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical apparatus such as an X-ray CT apparatus or a radiotherapy system, which aims at a spatial coordinate of an affected area from outside a patient by using a projector.
The present invention relates to a device for positioning a patient.

[0002]

2. Description of the Related Art When capturing a tomographic image of a patient using an X-ray CT apparatus, an effort is made to minimize the amount of X-ray exposure by limiting the imaging area of the patient. In radiotherapy equipment, efforts are made to administer optimal temporal and spatial dose distributions so as to maximize radiation damage to affected areas such as tumors and minimize the occurrence of damage to normal tissues. I have. In particular, in the case of a treatment device or a treatment planning device, dose planning is performed while maintaining a balance in consideration of the biological radiation sensitivity between the tumor and the surrounding organs. Therefore, the patient is set in the same place many times at intervals of time, and radiation therapy is performed. This provides accurate positioning of the patient at the location where the patient is set, for example, on a treatment couch.

Normally, as shown in FIG. 6, a patient 16 is placed on a bed 15 for positioning a patient, and aiming light 11 (laser beam or the like) is transmitted from three places, ie, left and right projectors 1a and 1c, and upper projector 1b of the patient 16. ) Is projected on the surface of the patient 16 with a cross mark 18, and this position is marked on the surface of the patient 16 with ink or the like. When the imaging or radiation treatment is completed and the patient 16 is repeatedly placed on the bed at a time interval (every other day, etc.) and the imaging or radiation treatment is performed, the patient 16 is set so that this mark matches the mark of the projector. Imaging or radiation treatment is performed in the same place.

[0004] A method of positioning an X-ray CT apparatus will be described with reference to FIGS. First, the patient 16 is placed on the bed 15 of the X-ray CT apparatus. Next, the gantry 17 of the X-ray CT apparatus
Rotation center 21 of patient 16 corresponding to the rotation center of X-ray tube
Position is determined by the following procedure. The projector 1a and the projector 1c are set at a predetermined height with the height of the rotation center of the apparatus parallel to the floor 14. Next, the upper projector 1b is positioned at the center of the apparatus, and is directed vertically toward the patient. The aiming light 11 is projected to the patient 16 from each of these three places. And bed 1
5 is moved up and down or the bed is moved back and forth and right and left so that the cross mark 18 shown in FIG. Then, in this state, the table of the bed 15 on which the patient 16 is placed is sent to a predetermined position of the gantry 17. The table is fixed on the spot, and X-ray CT imaging is performed.

[0005]

The projector as a patient positioning device in a conventional medical apparatus is constructed as described above, but the aiming lights 11 from the three projectors 1a, 1b and 1c must cross at one point. Must. Also, this intersection must exactly coincide with the center of rotation of the X-ray CT device, the treatment device, and the treatment planning device. Furthermore, the aiming light 11 of the light projectors 1a and 1b from the left and right must be emitted in parallel with the floor 14. The aiming light 11 of the projector 1b from above must be projected perpendicular to the floor 14. In addition, when projecting the cross mark 18, the line of the cross mark 18 must also be parallel / perpendicular to the floor 14. That is, for the left and right projectors 1a and 1c,
There are five parameters shown in FIG. 9, FIG. 10, and FIG. The height h of the light projector 1a from the floor 14 shown in FIG. 9 and the angle θ with the horizontal, the position of the light projector 1a in the direction of the patient body axis 19 of the patient 16 shown in FIG. 10, the angle between the patient 16 and the patient body axis 19 φ is the rotation angle γ from the horizontal position / vertical position of the cross projection light from the light projector 1a shown in FIG. Similarly, for the light projector 1b, the left and right, front and rear positions with respect to the patient body axis 19,
And the deflection angle. Some of these parameters must be adjusted to align the projectors 1a, 1b, 1c.

Various fine movement adjusters have been devised so that they can be easily adjusted, but there is a problem that it is difficult to adjust each parameter completely independently.
For example, even if the height h of the light projector 1a from the floor 14 is adjusted, there is a problem that the angle θ with the horizontal is changed at the same time. In addition, since the light projectors 1a, 1b, and 1c are usually a few meters away from the patient 16, the light projectors 1a,
There is a problem that the minute movements b and 1c are enlarged and cause a large displacement. Therefore, the adjustment of the light projectors 1a, 1b, 1c is a very troublesome operation.

The present invention has been made in view of such circumstances, and a medical apparatus in which the positions and angles of the light projectors 1a, 1b, and 1c can be easily and accurately adjusted without being affected by the already adjusted parameters. It is an object of the present invention to provide a patient positioning device in the above.

[0008]

In order to achieve the above object, a patient positioning device in a medical device according to the present invention is a projector for projecting a spatial coordinate of an affected part in a medical device for imaging or treating a patient from outside the patient. In a device for aiming and positioning of a patient, a block made of a transparent, bilaterally parallel, material having a uniform refractive index is provided on the optical axis at the front surface of the projector so as to be rotatable in the horizontal and vertical directions. The optical axis can be moved in parallel in the horizontal and vertical directions.

The patient positioning device in the medical device according to the present invention is configured as described above. After setting the height of the projector from the floor and the position with respect to the direction of the patient's body in advance, the patient is positioned on the optical axis in front of the projector. In order to translate the optical axis of the projector horizontally and vertically, a block made of a transparent and parallel material with a uniform refractive index is rotated in the horizontal and vertical directions. By shifting the aiming light in parallel, accurate alignment can be easily performed without being affected by the already adjusted parameters.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a patient positioning device in a medical device according to the present invention will be described with reference to FIG. 1A shows a side view, and FIG. 1B shows a front view.
The patient positioning apparatus holds a projector 1 having a light source for projecting the aiming light 11 and a transparent block 9 provided on an optical axis in front of the projector 1, and rotates around a vertical axis (φ axis 3). It comprises a frame 7 and a rotating frame 6 that rotates about a horizontal axis (θ-axis 2).

The light projector 1 usually has a laser light source inside, and the beam shape of the aiming light 11 of the light projection forms a cross shape, and a narrow beam can reach a distant place. The transparent block 9 is a transparent block having a predetermined thickness, both surfaces of which are optically parallel, a transparent material having a small light absorption loss and a good transmittance, and a uniform refractive index.
Then, the transparent block 9 is held by the rotating frame 7.
The rotating frame 7 is held up and down by the rotating frame 6 via the pieces 12, and can be finely rotated around the vertical axis (φ axis 3) by the rotary knob 4 and fixed. The rotating frame 6 is a fixed frame 8
Are supported via the piece 10 by the supporting columns 13 on both sides of the lens, and can be finely rotated around the horizontal axis (θ-axis 2) by the rotary knob 5 and fixed. Floodlight 1 on fixed frame 8
And the transparent block 9 are mounted so that the aiming light 11 from the light projector 1 enters the center of the transparent block 9 via the rotating frames 7 and 6.

FIG. 2 shows the relative relationship between the projector 1 and the transparent block 9. The surface A and the surface B of the transparent block 9 are set perpendicular to the aiming light 11 of the projector 1. A side and B
The surface is made of an optically parallel surface, and the aiming light 11 incident on the surface A exits perpendicularly from the surface B. Also transparent block 9
Is inclined, the output light is shifted by Δd with respect to the incident optical axis according to Snell's law due to the refractive index n and the thickness t of the transparent block 9, but the output optical axis is parallel to the incident optical axis. Proceed as The transparent block 9 is rotated (θ) back and forth around the point P by the rotating frame 7, and is rotated (φ) around the vertical axis passing through the point P by the rotating frame 6, so that the transparent block 9 is moved from the direction of the incident optical axis. The aiming light 11 can be shifted in parallel by Δd.

Next, the manner of operation using the present optical axis shift projector will be described in the horizontal direction with reference to FIGS. First, the patient 16 is placed on the bed 15. The bed 15 is moved up and down so that the floor 14 corresponding to the rotation center 21 of the apparatus
The center of the patient is positioned so that the height from the patient is h. Then, the optical axis shift projector of the horizontal position on which the projector 1 and the transparent block 9 are mounted is moved up and down, and the height is adjusted by paying attention only to θ, that is, the optical axis (aiming light 11) is parallel to the floor 14. And the height h from the floor 14 is roughly h
+ Α and fix. Next, as shown in FIG. 4, the transparent block 9 is tilted in the θ direction and the aiming light 11 is shifted horizontally with respect to the floor 14 to adjust the height h. Light passing through the oblique transparent block 9 is refracted at the time of incidence and refracted at the time of emission. Since the transparent block 9 is homogeneous and the entrance / exit surfaces are parallel, the refraction angles at the entrance / exit are exactly equal. Therefore, the incident light and the output light become exactly parallel, and the optical axis shifts by Δ.

At this time, the height h from the floor 14 and the vertical swing angle θ can be adjusted completely independently. That is, even if the transparent block 9 is tilted, θ never changes. This makes the adjustment very easy. In the actual adjustment, h, θ,
The five parameters y, φ, and γ are matched.
According to the present optical axis shift projector, first, θ, φ, and γ can be accurately adjusted, and then, the transparent block 9 can be tilted so that h and y can be adjusted without affecting the already adjusted θ, φ, and γ. .

In the above embodiment, the transparent block 9 is described as having a circular shape. However, the present invention can be similarly applied to shapes other than the circular shape. The method of tilting the transparent block 9 is as follows.
In the above-described embodiment, the rotation is performed by the rotary knob 4 and the rotary knob 5 and fixed. However, the present invention is not limited to this, and a method of rotating and fixing by another method may be used.

In the above embodiment, the transparent block 9 is constituted by one block. However, as shown in FIG. 5, the transparent block 9 is constituted by two transparent blocks 9a having only a φ rotation and a transparent block 9b having only a θ rotation. Optical axis shift method may be used.

Furthermore, the optical axis shift projector can be used not only for determining the position of the tomographic image of the X-ray CT apparatus and the MRI apparatus, but also for aiming the radiation therapy apparatus. Or can be intensively treated.

[0018]

The patient positioning apparatus provided by the present invention is constructed as described above. After setting the height of the projector from the floor and the position in the direction of the patient's body in advance, the patient positioning apparatus is positioned on the optical axis in front of the projector. In addition, the horizontal and vertical rotation of a block of transparent, parallel, two-sided material with a uniform refractive index can easily shift the aiming light from the projector in parallel, affecting the parameters already adjusted. Accurate positioning can be easily performed without being performed.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of an optical axis shift projector in a patient positioning apparatus of the present invention.

FIG. 2 is a view showing a side surface of a transparent block rotation of the optical axis shift projector in the patient positioning apparatus of the present invention.

FIG. 3 is a diagram showing a horizontal aiming step of the optical axis shift projector in the patient positioning apparatus of the present invention.

FIG. 4 is a view showing a horizontal aiming method of the optical axis shift projector in the patient positioning apparatus of the present invention.

FIG. 5 is a view showing another embodiment of the optical axis shift projector in the patient positioning apparatus of the present invention.

FIG. 6 is a view showing aiming of an optical axis projector used in a conventional CT apparatus.

FIG. 7 is a diagram showing a conventional aiming method for an optical axis projector.

FIG. 8 is a view showing a state where a cross mark of a conventional optical axis projector is aimed.

FIG. 9 is a diagram showing a height of a light sight and an angle in a vertical direction when an optical axis projector is set.

FIG. 10 is a diagram illustrating a depth position and a horizontal angle of a light sight when an optical axis projector is set.

FIG. 11 is a diagram showing the inclination of a cross mark for light aiming when the optical axis projector is set.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Floodlight 1a ... Floodlight 1b ... Floodlight 1c ... Floodlight 2 ... θ-axis 3 ... φ-axis 4 ... Rotary knob 5 ... Rotary knob 6 ... Rotating frame 7 ... Rotating frame 8 ... Fixed frame 9 ... Transparent block 9a ... Transparent block 9b ... Transparent block 10 ... piece 11 ... sight light 12 ... piece 13 ... post 14 ... floor 15 ... bed 16 ... patient 17 ... gantry 18 ... cross mark 19 ... patient body axis 21 ... rotation center

Claims (1)

[Claims] 1. A device for positioning a patient in a medical device for imaging or treating a patient by positioning a spatial coordinate of an affected part from outside of the patient by a projector, wherein the device is transparent, both planes are parallel and the refractive index is uniform. A medical device, wherein a block made of a material is rotatable in the horizontal and vertical directions and provided on the optical axis in front of the projector, so that the optical axis of the projector can be translated in the horizontal and vertical directions. Patient positioning device.