KR20210006659A - Angle-variable collimator and radiation detection device using the same - Google Patents

Abstract

The present invention relates to a variable angle collimator and a radiation detection device using the same. The angle-variable collimator according to the present invention includes a plurality of unit holes formed on each plate surface, a plurality of hole plates stacked in the plate surface direction, and a plate driving part for adjusting a gap in the stacking direction between the plurality of hole plates. ; The unit holes at positions corresponding to each other between the hole plates are communicated along the stacking direction to form an incident hole of radiation in the stacking direction; An interval between the unit holes adjacent to each other of each of the hole plates increases in the stacking direction so that the inclination angle increases as the incident hole goes toward the edge of the hole plate; The plate driving unit is achieved by an angle-variable collimator, characterized in that the inclination angle of the incident hole is adjusted by adjusting the spacing between the hole plates. Accordingly, it is possible to adjust the diffusion angle and the focusing angle while being applied to a focusing porous collimator or a diffusion porous collimator in a radiation detection apparatus such as a gamma camera or a single photon emission computed tomography apparatus.

Description

Angle variable collimator and radiation detection device using the same {ANGLE-VARIABLE COLLIMATOR AND RADIATION DETECTION DEVICE USING THE SAME}

The present invention relates to an angle variable collimator and a radiation detection device using the same, and more particularly, a focused porous collimator in a radiation detection device such as a gamma camera or a single photon emission computed tomography (SPECT) device, It relates to an angle variable collimator applicable to a diffusion porous collimator and a pinhole collimator, and a radiation detection device using the same.

A radiation detection device is a device for detecting or imaging radiation using radioactive isotopes, and is one of the devices widely used in the field of non-destructive testing including nuclear medicine diagnosis.

Radiation detection devices used in the field of nuclear medicine diagnosis, for example, gamma ray cameras using gamma rays or single photon emission computed tomography devices, are other diagnostic devices that provide structural information of the human body, such as magnetic resonance imaging (MRI) or ultrasound. Unlike diagnostic devices, radioactive drugs are used to provide functional information on the human body.

1 is a diagram showing the configuration of a conventional gamma camera 1. A typical gamma camera 1 includes a collimator 10 and a radiation detector 20 that detects radiation that has passed through the collimator 10.

The collimator 10 functions as a collimator that passes only gamma rays in a specific direction among gamma rays emitted from a tracer in a living body and blocks gamma rays from other directions. That is, the collimator 10 geometrically restricts gamma rays emitted from a living body region and causes only gamma rays emitted from a necessary region to enter the radiation detector 20.

The collimator 10 shown in FIGS. 1, 2 and 3 (a) is a view showing an example of a parallel multi-hole collimator in which a plurality of holes is formed, and FIG. 3 (b), (c) and (d) represent a Diverging multi-hole collimator, a Converging multi-hole collimator, and a Pin-hole collimator, respectively.

The parallel porosity collimator is the most widely used because the arrangement of holes is parallel, and there is no change in image size depending on the distance between the collimator and the measurement object, and to increase resolution and sensitivity, the distance to the measurement object is shortened. In general, the partition wall for low energy use is thin, and the partition wall becomes thicker as the energy increases.

Diffusion-porous collimators are used to inspect a measurement object larger in size than the effective diameter of the collimator, and the image resolution is relatively low. As the distance between the collimator and the measurement object increases, the effective field of view becomes wider, but the sensitivity and resolution decrease.

The pinhole collimator has a high resolution and is useful for inspection of small targets or local areas. In order to increase sensitivity and improve resolution, the distance between the object to be measured and the collimator must be short, and if the distance to the object to be measured increases, the image is reduced.

The focusing porous collimator can be seen as a mixed type of parallel porous collimator and pinhole collimator, and the image is enlarged as the distance between the collimator and the measurement object is closer, and the image is reduced as the real object is closer to the focus.

Referring again to FIG. 1, the radiation detection unit 20 may include a scintillator 21, a light guide unit 22, and an optical multiplier 23. The gamma ray passing through the collimator 10 is incident on the scintillator 21.

Here, the gamma ray that has passed through the collimator 10 and reacted with the scintillator 21 is converted into a low-energy electromagnetic wave in a form that is easy to be detected by the scintillator 21, and passes through the optical guide unit 22 to the photomultiplier tube 23. ) Is amplified and converted into an electric signal, and the detected position or energy is stored in a computer (not shown) to obtain an image.

A single photon emission computed tomography apparatus using the principle of a gamma ray camera as described above was established in 1976. First developed by W. I. Keys, 1979. A brain-specific device was developed by R. J. Jaszczak.

The single photon emission computed tomography apparatus is similar to the operation principle of the gamma camera 1, in which a single photon, for example, a radiopharmaceutical that emits gamma rays is injected into the living body T so that gamma rays generated in the living body penetrate the living body As shown in FIG. 2, a gamma ray camera installed in a gantry (not shown) rotating around a living body is measured at various angles, and a tomography image is obtained by using an image reconstruction algorithm.

Accordingly, the collimator 10 and the gamma ray detector 20 are applied to the single photon emission computed tomography apparatus as well as the gamma ray camera 1.

Here, in the case of the pinhole collimator, the diffusion porous collimator, and the focusing porous collimator, there is a disadvantage that the angle of view of the hole is fixed constant. This is because each resolution or image size varies according to the distance to the object to be measured. If the angle of view can be adjusted according to the detection situation, various images can be acquired without replacing the collimator.

Accordingly, in the'variable pinhole type collimator and radiation detection device using the same' disclosed in Korean Patent Publication No. 10-1364339 filed and published by the applicant of the present application, a pinhole collimator with an adjustable angle of view has been proposed.

However, in the case of a focusing porous collimator or a diffusion porous collimator as shown in FIG. 4, the angle of view is fixed, and there is a need to develop an angle variable collimator capable of adjusting the focusing angle or the diffusion angle.

Accordingly, the present invention has been devised to solve the above problems, and in a radiation detection device such as a gamma camera or a single photon emission computed tomography (SPECT) device, a focusing porous collimator, a diffusion porous type An object thereof is to provide a collimator and an angle variable collimator applicable to a pinhole collimator, and a radiation detection device using the same.

According to the present invention, in the angle-variable collimator, a plurality of unit holes are formed on each plate surface, and a plurality of hole plates stacked in the plate surface direction, and a spacing between the plurality of hole plates in the stacking direction are adjusted. And a plate driving unit; The unit holes at positions corresponding to each other between the hole plates are communicated along the stacking direction to form an incident hole of radiation in the stacking direction; An interval between the unit holes adjacent to each other of each of the hole plates increases in the stacking direction so that the inclination angle increases as the incident hole goes toward the edge of the hole plate; The plate driving unit is achieved by an angle-variable collimator, characterized in that the inclination angle of the incident hole is adjusted by adjusting the spacing between the hole plates.

Here, the size of the unit hole of each hole plate may increase toward the stacking direction.

In addition, the inner wall surface of each unit hole may be formed to be inclined corresponding to the inclination direction of the incident hole.

In addition, the plate driving unit is formed in each of the hole plates at positions corresponding to each other, a guide hole having an inner diameter threaded therein, and a guide hole passing through the guide holes in the stacking direction and having an outer diameter screwed with a thread of the inner diameter of the guide hole. It may include a guide bar having a threaded thread, and a driving motor that rotates the guide bar to adjust a gap between the plurality of hole plates in the stacking direction.

In addition, the plate driving unit pushes at least one elastic spring having an elastic force in a direction spaced apart from each other by being disposed between the hole plates adjacent to each other, and pushing the hole plate on one side of the stacking direction of the hole plate in the other direction. And a pressing module for adjusting a gap between the hole plates in the stacking direction, and the elastic modulus of the elastic spring is formed to be the same, so that the gap between the hole plates may be uniformly adjusted by the pressing of the pressing module.

Here, the spacing between the unit holes adjacent to each other of each of the hole plates may increase only in a horizontal direction or a vertical direction of the plate surface of the hole plate.

On the other hand, the above object is, in accordance with another embodiment of the present invention, in an angle-variable collimator, a unit hole is formed on each plate surface, and a plurality of hole plates stacked in the direction of the plate surface, and the size of the unit holes are different from each other and are stacked. Forming a pinhole in the direction; It is also achieved by a variable angle collimator, characterized in that it comprises a plate driving unit for adjusting the angle of view of the pinhole by adjusting the spacing between the plurality of hole plates in the stacking direction.

On the other hand, according to another embodiment of the present invention, in accordance with another embodiment of the present invention, there is provided a radiation detection apparatus, comprising: the variable angle collimator; A radiation detector configured to detect radiation passing through the incident holes of the angle-variable collimator; A radiation image processing unit for imaging the radiation detected by the radiation detection unit; It can also be achieved by a radiation detection device comprising a control unit for controlling the plate driving unit of the angle variable type collimator so that the inclination angle of the incident holes of the angle variable type collimator is adjusted.

Here, the angle-variable collimator is installed so that the direction in which the inclination angles of the incident holes are diffused toward the measurement target, the angle-variable collimator may operate as a diffusion porous collimator.

In addition, the angle-variable collimator is installed so that the direction in which the inclination angles of the incident holes are focused is toward the object to be measured, so that the angle-variable collimator can operate as a focusing porous collimator.

And, further comprising a gantry for rotating the angle variable collimator and the radiation detection unit around the measurement object; The control unit may adjust the inclination angle of the incident hole of the angle variable collimator based on a change in distance between the measurement object and the angle variable collimator and the size of the measurement object as the angle variable collimator rotates around the measurement object. have.

According to the above configuration, according to the present invention, while being applied to a focusing porous collimator, a diffusion porous collimator, and a pinhole collimator in a radiation detection device such as a gamma camera or a single photon emission computed tomography apparatus, the diffusion angle, the focusing angle or the angle of view There is provided an angle-variable collimator capable of adjusting of and a radiation detection device using the same.

1 is a diagram showing the configuration of a conventional gamma camera,
2 is a view for explaining the operating principle of the single photon emission computed tomography apparatus,
3 is a diagram for explaining the type of a conventional collimator,
4 is a view showing an example of a conventional diffusion porous collimator,
5 and 6 are views for explaining an angle variable collimator according to the present invention,
7 is an example of a plan view of a hole plate of an angle variable collimator according to the present invention,
8 is another example of a plan view of a hole plate of an angle-variable collimator according to the present invention,
9 is a view for explaining an example of adjusting the inclination angle of the incident hole of the angle variable collimator according to the present invention,
10 is a view showing an example of the plate driving unit of the angle variable collimator according to the present invention,
11 is a view showing another example of the plate driving unit of the angle variable collimator according to the present invention,
12 and 13 are views showing the configuration of an angle variable collimator according to another embodiment of the present invention,
14 is a view for explaining a radiation detection apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The variable angle collimator 100 according to the present invention is applied to a radiation detection device such as a gamma camera or a single photon emission computed tomography apparatus. Although the present invention is applied to a radiation detection device for nuclear medicine as an example, the angle variable collimator 100 according to the present invention can be applied to a radiation detection device or a radiation test device for non-destructive testing using gamma rays.

5 and 6 are views for explaining the angle-variable collimator 100 according to the present invention, and FIG. 7 is an example of a plan view of the hole plate 110a of the angle-variable collimator 100 according to the present invention.

5 to 7, the angle variable collimator 100 according to the present invention includes a plurality of hole plates 110a to 110i and a plate driving unit 200.

The plurality of hole plates 110a to 110i are stacked in the direction of the plate surface. In addition, a plurality of unit holes 111 are formed on the plate surface of each of the hole plates 110a to 110i. 7 illustrates that the hole plates 110a to 110i have a square plate shape and a plurality of unit holes 111 are arranged in a matrix form, but the shape of the hole plates 110a to 110i and the plurality of unit holes ( Of course, the arrangement of 111) is not limited thereto. In addition, although it is assumed that each unit hole 111 has a square shape, of course, it may be formed in a hexagonal shape such as a honeycomb.

Here, the unit holes 111 at positions corresponding to each other between the hole plates 110a to 110i are communicated along the stacking direction to form an incident hole 130 of radiation in the stacking direction. And, the spacing between the mutually adjacent unit holes 111 of each of the hole plates 110a to 110i increases in the stacking direction, so that the inclination angle increases as the incident hole 130 goes toward the edge of the hole plates 110a to 110i. Is formed to be

According to the configuration as described above, the unit holes 111 at corresponding positions each form one incident hole 130 in the stacking direction, and the hole plates 110a to 110i go upward based on FIG. 5. As the interval between the unit holes 111 formed in the is widened, the incident hole 130 is formed to be inclined at a predetermined angle with respect to the stacking direction.

Here, when the radiation detection unit 320 is disposed at the bottom so that the incident direction of radiation is formed from the top to the bottom, the plurality of hole plates 110a to 110i operate as a diffusion porous collimator, and conversely, the radiation detection unit 320 When is disposed on the top and the incident direction of radiation is formed from the bottom to the top, the plurality of hole plates 110a to 110i can operate as a focusing porous collimator.

In FIG. 7, each of the unit holes 111 has an approximately square shape, and the size and spacing of the unit holes 111 are increased in the horizontal and vertical directions, but as shown in FIG. 7, It goes without saying that the size and spacing may be widened only in any one of the horizontal and vertical directions. In this case, the present invention is not limited that the unit hole 111 having the smallest size has a square shape, and of course, it may be formed in a rectangular shape.

On the other hand, the plate driving unit 200 adjusts the spacing between the plurality of hole plates 110a to 110i in the stacking direction. FIG. 5 is a diagram illustrating a state in which a plurality of hole plates 110a to 110i are in close contact with each other in the stacking direction, and FIG. 6 is a view illustrating a state in which the plurality of hole plates 110a to 110i are spaced apart from each other in the stacking direction. Here, a specific embodiment of the plate driving unit 200 will be described later.

Here, as shown in FIGS. 5 and 6, when the plate driving unit 200 adjusts the distance between the hole plates 110a to 110i, the inclination angle of the incident hole 130 is adjusted, as shown in FIG. Likewise, the inclination angle can be adjusted according to the adjustment of the distance between the hall plates 110a to 110i within the angle range α1 and α2.

Meanwhile, the size of the unit hole 111 of each of the hole plates 110a to 110i may be provided to increase in the stacking direction. That is, the spacing between the unit holes 111 and the size of the unit holes 111 may be provided to increase proportionally toward the stacking direction. Through this, the distance between the unit holes 111 and the size of the unit holes 111 are appropriately adjusted, so that it is possible to easily adjust the angle of incidence desired by the designer.

In addition, in FIGS. 5 and 6, the inner wall surface of each unit hole 111 is formed in parallel with the vertical direction, but of course, it may be formed to be inclined corresponding to the inclination direction of the incident hole 130. .

Hereinafter, an embodiment of the plate driving unit 200 according to the present invention will be described with reference to FIGS. 10 and 11.

First, referring to FIG. 10, the plate driving unit 200 according to the present invention may include a guide hole, a guide bar 220, and a driving motor 210.

Guide holes (not shown) are formed in each of the hole plates 110a to 110i at positions corresponding to each other. In addition, the guide bar 220 is formed through the guide holes in the stacking direction. In this case, a thread is formed in the inner diameter of the guide hole and the outer diameter of the guide bar 220 so that the guide bar 220 is screwed to each of the hole plates 110a to 110i.

Here, when the driving motor 210 rotates the guide bar 220, the spacing between the plurality of hole plates 110a to 110i in the stacking direction can be adjusted, and any one hole plate 110a among the edges in the stacking direction is ~110i) may not have a thread formed in the inner diameter of the guide hole so that the fixed position is maintained. In addition, if the pitch of the thread is different according to the position of each of the hole plates 110a to 110i, as shown in Figs. 5 and 6, the hole plates 110a to 110i can be adjusted while maintaining the same distance. do.

Meanwhile, the plate driving unit 200 according to the embodiment shown in FIG. 11 may include an elastic spring 220a and a pressing module 210a.

The elastic springs 220a are disposed between the mutually adjacent hole plates 110a to 110i to provide elastic force in a direction spaced apart from each other. Here, a spring hole 112 is formed in the hole plates 110a to 110i to block the elastic spring 220a from moving between the hole plates 110a to 110i.

The pressing module 210a pushes the hole plate 110a to 110i on either side of the stacking direction of the hole plate 110a to 110i, that is, the top hole plate 110a to 110i shown in FIG. 11 in the other direction. The spacing in the stacking direction between the hole plates 110a to 110i of is adjusted. Here, when the elastic modulus of the elastic spring 220a is formed to be the same, the spacing between the hole plates 110a to 110i can be adjusted in a constant state by the family business of the pressing module 210a.

12 and 13 are diagrams showing the configuration of an angle variable collimator 200 according to another embodiment of the present invention. The angle variable collimator 200 shown in FIGS. 12 and 13 is an example of a pinhole collimator.

Referring to FIGS. 12 and 13, unit holes are formed on the plate surfaces of each of the hole plates 200a to 200n. In addition, when the size of the unit holes is formed differently for each of the hole plates 200a to 200n so that the plurality of hole plates 200a to 200n are stacked in the direction of the plate surface, as shown in FIG. 12, the unit holes are formed in the stacking direction. A pinhole is formed.

At this time, when the plate driving unit (not shown) adjusts the spacing between the plurality of hole plates 200a to 200n in the stacking direction, as shown in FIGS. 12 and 13, the angles of view (θ1, θ2) of the pinhole are Becomes adjustable.

Hereinafter, a radiation detection apparatus according to an embodiment of the present invention will be described in detail with reference to FIG. 14. Here, in the radiation detection apparatus according to the present invention, it is assumed that the angle variable collimator 100 is applied.

As illustrated in FIG. 14, the radiation detection apparatus according to the present invention includes a plate driving unit 200, a radiation detection unit 320, a radiation image processing unit 330, and a control unit 310. In addition, as described above, the plate driving unit 200 adjusts the spacing between the plurality of hole plates 110a to 110i of the angle-variable collator.

The radiation detection unit 320 detects radiation, such as gamma rays, that have passed through the incident hole 130 formed by the angle-variable collimator 100. In the present invention, the configuration of the radiation detection unit 320 may have various known forms capable of detecting radiation.

The radiation image processing unit 330 images the radiation detected by the radiation detection unit 320. When the radiation detection apparatus according to the present invention is provided in the form of a single photon emission computed tomography apparatus, the radiation image processing unit 330 uses radiation detected at various angles according to the rotation of the gantry 340 through an image reconstruction algorithm. A tomographic image is formed.

The control unit 310 controls the plate driving unit 200 so that the inclination angle of the incident hole 130 of the angle-variable collimator 100 is adjusted to suit the measurement target emitting radiation, for example, a lesion in a living body. .

For example, when the lesion is located in the right lung of the patient while the patient is lying down, the distance between the angle-variable collimator 100 and the lesion is as when the angle-variable collimator 100 rotates by the gantry 340 and is located on the left side. When it is located on the right, it changes.

Accordingly, the controller 310 determines an appropriate inclination angle of the incidence hole 130 based on the previously registered distance information between lesions, and adjusts the inclination angle of the incidence hole 130 according to the rotation position of the gantry 340. The plate driving unit 200 may be controlled.

That is, as the angle variable collimator 100 rotates around the measurement object, the control unit 310 is based on the change in the distance between the measurement object and the angle variable collimator 100 and the size of the measurement object, the incident of the angle variable collimator 100 The inclination angle of the hole 130 can be adjusted.

Although some embodiments of the present invention have been shown and described, those skilled in the art of ordinary skill in the art to which the present invention pertains will appreciate that the present embodiments can be modified without departing from the principles or spirit of the present invention. . The scope of the invention will be determined by the appended claims and their equivalents.

100: angle variable collimator 110a~110i: hole plate
111: unit hole 112: spring hole
130: entrance hole
200: plate drive unit 210: drive motor
220: guide bar 210a: pressing module
220a: elastic spring 310: control unit
320: radiation detection unit 330: radiation image processing unit
340: gantry

Claims (11)

In the angle variable collimator,
A plurality of unit holes are formed on each plate surface, a plurality of hole plates stacked in the direction of the plate surface,
A plate driving unit for adjusting a spacing between the plurality of hole plates in a stacking direction;
The unit holes at positions corresponding to each other between the hole plates are communicated along the stacking direction to form an incident hole of radiation in the stacking direction;
An interval between the unit holes adjacent to each other of each of the hole plates increases in the stacking direction so that the inclination angle increases as the incident hole goes toward the edge of the hole plate;
The plate driving unit adjusts the inclination angle of the incident hole by adjusting the distance between the hole plates. The method of claim 1,
An angle variable collimator, characterized in that the size of the unit hole of each of the hole plates increases toward the stacking direction. The method of claim 1,
An angle variable collimator, characterized in that the inner wall surface of each unit hole is formed to be inclined corresponding to the inclination direction of the incident hole. The method of claim 1,
The plate driving part
A guide hole formed in each of the hole plates at positions corresponding to each other and having a threaded inner diameter,
A guide bar having a thread formed in an outer diameter so as to penetrate the guide holes in the stacking direction and screwed with a thread of the inner diameter of the guide hole,
And a driving motor configured to rotate the guide bar to adjust an interval between the plurality of hall plates in the stacking direction. The method of claim 1,
The plate driving part
At least one elastic spring disposed between the adjacent hole plates and having elastic force in a direction spaced apart from each other,
And a pressing module configured to adjust a gap between the plurality of hole plates in the stacking direction by pushing a hole plate on one side of the stacking direction of the hole plate in the other direction,
The elastic modulus of the elastic spring is formed equally, the angle variable collimator, characterized in that the spacing between the hole plates is uniformly adjusted by the pressing of the pressing module. The method of claim 1,
An angle variable collimator, characterized in that an interval between the unit holes adjacent to each other of the hole plates increases only in a horizontal direction or a vertical direction of the plate surface of the hole plate. In the angle variable collimator,
A plurality of hole plates having a unit hole formed on each plate surface, and stacked in a direction of the plate surface, and-the size of the unit holes are different from each other to form a pinhole in the stacking direction;
And a plate driving unit configured to adjust an angle of view of the pinhole by adjusting an interval between the plurality of hole plates in a stacking direction. In the radiation detection device,
The angle variable collimator according to any one of claims 1 to 6;
A radiation detector configured to detect radiation passing through the incident holes of the angle-variable collimator;
A radiation image processing unit for imaging the radiation detected by the radiation detection unit;
And a control unit for controlling the plate driving unit of the angle-variable collimator so that the inclination angles of the incident holes of the angle-variable collimator are adjusted. The method of claim 8,
The angle-variable collimator is installed in a direction in which the inclination angles of the incident holes are diffused toward the measurement object, and the angle-variable collimator operates as a diffusion porous collimator. The method of claim 8,
The angle-variable collimator is installed in a direction in which the inclination angles of the incident holes are focused toward the object to be measured, and the angle-variable collimator operates as a focusing porous collimator. The method of claim 8,
And a gantry rotating the angle-variable collimator and the radiation detection unit around a measurement object;
The control unit adjusts the inclination angle of the incident hole of the angle variable collimator based on a change in distance between the measurement object and the angle variable collimator and the size of the measurement object as the angle variable collimator rotates around the measurement object. Radiation detection device, characterized in that.

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