JP3419654B2 - X-ray diagnostic equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an over-tube type X-ray diagnostic apparatus, and more particularly to a bed detector by providing a flat detector capable of downsizing and thinning an image intensifier in the bed. The present invention relates to an X-ray diagnostic apparatus capable of descending to near the floor to facilitate the getting on and off of a patient.

[0002]

2. Description of the Related Art Conventionally, an over-tube type X-ray diagnostic apparatus as shown in FIG. 7 is known.

This X-ray diagnostic apparatus supports a bed 100 on which a patient is placed, an X-ray tube 101 for irradiating a patient placed on the bed 100 with X-rays, and an X-ray tube 101. X
It has a line support 102. Further, the bed 100 is provided in the bed so as to face the X-ray tube 101 and the bed driving unit 103 that drives the bed 100 in the vertical direction (up and down) with respect to the floor on which the X-ray diagnostic apparatus is placed. Image intensifier 104 (II) and I.I. And a television camera device 105 that captures a visible image from I104.

Such an X-ray diagnostic apparatus has a bed driving unit 1
The bed 100 is driven downward by 03 to move the patient to the bed 100.
Then, the patient is exposed to X-rays from the X-ray tube 101. The I.D. I104
Converts the X-ray image formed by passing the exposed X-ray through the patient into a visible image. The television camera device 105 captures this visible image and supplies the television signal thus formed to the monitor device.

As a result, on the display screen of the monitor device,
A fluoroscopic image or a captured image corresponding to the X-ray image can be displayed, and a doctor or the like can make a treatment plan based on the fluoroscopic image or the captured image.

[0006]

However, such a conventional over-tube type X-ray diagnostic apparatus has a large volume I.V. formed by a vacuum tube as an X-ray image detecting means. I104
The I.I.
There was a problem that the bed 100 could not be lowered below the height at which the I104 was provided, making it difficult for a physically handicapped patient to get on and off the bed 100.

For example, in chest radiography, the focus of the X-ray tube 101, which is an X-ray generating means, and the I.I. Although a distance of 1.5 m to 2.0 m is required between the I.I. Since the bed 100 cannot be lowered below the height at which the I.I 104 is provided, the focus of the X-ray tube 101 and the I.I. There is a problem that it is difficult to take a sufficient distance from I104 and it becomes difficult to photograph the chest and the like.

Although this problem can be solved by providing a mechanism for driving the X-ray tube 101 up and down,
For that purpose, it is necessary to newly provide such an up-and-down drive mechanism for the X-ray tube 101, which causes structural and cost problems.

In addition, I.D. The output image from I104 (the visible image) has a circular shape with a diameter of, for example, 15 mm to 30 mm, so that the field of view (display image of the monitor device) is circular, and the display image is unsuitable for observing the human body. There was a problem that I could not get.

Furthermore, I.D. The I104 has a problem of causing geometrical and magnetic distortion in a display image due to scanning with an electron beam or the like.

The present invention has been made in view of the above-mentioned problems, and makes it possible to greatly lower the bed so that a patient can easily get on and off the bed, and X-ray generation means and X-ray detection means are provided. It is an object of the present invention to provide an X-ray diagnostic apparatus capable of obtaining a sufficient distance between the human body and a display image having a shape suitable for observing a human body, which is free of geometrical and magnetic distortion. And

[0012]

In order to achieve the above object, the present invention provides a bed on which a subject is placed, a bed support for supporting the bed so that the bed can be raised and lowered, and a bed mounted on the bed. An X-ray tube for irradiating the subject with X-rays, an X-ray tube supporting means for supporting the X-ray tube, and the X-ray tube supporting means obliquely with respect to the subject. An X-ray tube support control unit that controls rotation so that X-rays are emitted and a bed are connected to the bed so as to be position-controllable independently of the up-and-down movement of the bed. A solid-state flat panel detector for detecting with a plurality of solid-state detecting elements arranged in a dimension, wherein the solid-state flat panel detector is configured to rotate the X-ray tube supporting means by the X-ray tube supporting control means. The position of the X-ray detection surface of the flat panel detector is controlled so as to face the X-ray exposure surface of the X-ray tube. It is an. In addition, a bed on which the subject is placed, a bed support for supporting the bed so as to be able to move up and down, and an X for the subject placed on the bed.
The X-ray tube for irradiating the X-ray, the X-ray tube supporting means for supporting the X-ray tube, and the X-ray tube supporting means are arranged so that the X-ray is obliquely exposed to the subject. X-ray tube support control means for controlling rotation and a plurality of solids which are connected to the bed so that position control is possible independently of vertical movement of the bed and two-dimensionally array the transmitted X-rays of the subject. A solid-state flat panel detector for detecting with a detection element, and a bellows-shaped cover provided below the bed and covering the solid-state flat panel detector are provided.

The X-ray diagnostic apparatus according to the present invention irradiates X-rays from above a subject placed on a bed so that the X-rays transmitted through the subject are located below the bed surface of the bed. This is a so-called over-tube type X-ray diagnostic apparatus that detects with an X-ray detector provided.

The solid-state flat panel detector used as the X-ray detector is constructed by arranging a plurality of solid-state detecting elements in a two-dimensional array, and is smaller than the image integrator formed by a vacuum tube. Yes, and very thin. Specifically, the thickness of the image intensifier can be thinned from a fraction of the image intensifier to a few tenths.

Due to the thinness of the solid-state flat panel detector, when the bed is moved down, it can be lowered to the vicinity of the floor, thereby facilitating the getting on and off of the bed of a physically handicapped patient. it can

Further, since the bed can be largely lowered in this way, a sufficient distance can be provided between the X-ray tube and the X-ray detector, and a chest radiographing which requires a sufficient distance at the time of radiography. Etc. can be easily implemented.

The solid-state flat panel detector is adapted to electrically read out the electric charge (electric charge storage type) or the voltage (voltage read-out type) formed by each solid state detection element according to the X-ray image. Since the electron beam scanning or the like unlike the intensifier is not necessary, a clear display image can be obtained without causing geometrical or magnetic distortion in the display image.

Further, by making the X-ray detection surface of the solid-state flat panel detector rectangular, it is possible to display a rectangular display image on the display means such as a monitor device, and an image of a shape suitable for observing a human body. Can be displayed.

Further, the X-ray emitted from the X-ray tube is a so-called cone beam, and the range of X-ray irradiation at the center of the subject is controlled by vertically moving the bed and the solid-state detector. Diameter and the corresponding X on the solid-state flat panel detector
The ratio of the diameter of the exposed area of the wire changes.

That is, when the bed is controlled to be raised, the diameter of the X-ray exposure range at the center of the subject is reduced, so that the display image is enlarged, and when the bed is controlled to be lowered, the X-ray exposure to the center of the subject is performed. Since the diameter of the range becomes large, the display image is reduced.
Thereby, a doctor or the like can obtain a display image with a desired enlargement ratio simply by raising and lowering the bed, and can facilitate subsequent treatment planning.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of an X-ray diagnostic apparatus according to the present invention will be described in detail below with reference to the drawings.

First, the X-ray diagnostic apparatus according to the first embodiment of the present invention is a so-called over-tube type X-ray diagnostic apparatus, on which a patient is placed as shown in FIG. 1 (a). The bed 1 is placed on the bed 1, the bed 1 and the bed column 2 that supports the bed 1 so that the bed 1 can move in a direction approaching the floor and a direction separating from the floor (hereinafter, the movement in this direction is referred to as vertical movement). X-ray tube 3 for exposing X-rays from above the patient, and X-ray tube 3
And an X-ray support column 4 for fixing and supporting the so as not to move up and down.

Further, this X-ray diagnostic apparatus is provided in the bed 1.
A solid-state flat panel detector 5 provided so as to face the X-ray tube 3, a support stand 6 for supporting the entire X-ray diagnostic apparatus, and X-rays from the X-ray tube 3 depending on the imaging range of the patient. It has an X-ray diaphragm 7 for narrowing down the exposure range and a moving mechanism (not shown) for moving the solid-state flat panel detector 5 up and down together with the bed 1.

This moving mechanism is provided with an existing mechanism for moving the bed 1 up and down. When the bed 1 is moved up and down by this moving mechanism, the bed 1 is interlocked with this. The solid-state flat panel detector 5 provided in 1 is moved up and down.

As shown in FIG. 2, the solid-state flat panel detector 5 is constructed by arranging a plurality of X-ray detecting elements consisting of pixels 11 and thin film transistors (TFTs) 12 two-dimensionally in the column and row directions. Overall, the aspect ratio is 3: 4 in the vertical and horizontal directions (9:16 aspect ratio if HD compatible,
It has a rectangular shape of HD (High Definition).

Each pixel 11 converts a X-ray into visible light and forms a charge according to the amount of the visible light, and a capacitor for storing the charge formed by the photodiode (storage capacitor). The TFT 12 operates as a switch for reading out the electric charge stored in the storage capacitor of each pixel 11.

The connection point between the cathode terminal of the photodiode and one terminal of the storage capacitor is the power line 15-.
1, 15-2 ... 15-n depending on the reverse bias power supply (-
Vn), and the connection point between the anode terminal of the photodiode and the other terminal of the storage capacitor is the TFT 12
Is connected to the source terminal of.

The gate terminal of the TFT 12 is commonly connected to each row by the read lines 13-1, 13-2, ... 13-n, and is connected to each line output terminal of the line driving section 14.

The drain terminal of each TFT 12 has a corresponding vertical transfer line 16-1, 16-2 ... 16-.
n is commonly connected to each column, and each switch 18- of the multiplexer 18 is connected via each readout amplifier 17.
1, 18-2 ... 18-n.

The control unit 10 controls ON / OFF of each TFT 12 connected to each readout line 13-1, 13-2, ... 13-n via the line driving unit 14, and is stored in each storage capacitor. The charge is read out and controlled, and the vertical transfer lines 16-1, 16-2 ... 16-n are thereby controlled.
The electric charge appearing at the output terminal is output to the monitor side via the output terminal 19 by selectively controlling the multiplexer 18.

More specifically, each pixel 11 and TFT
The cross section of the X-ray detection element composed of 12 is as shown in FIG. 3, and the TFT region 26 and the pixel region 27 (PD region) are provided on the support 25.

SiN is formed on the support 25 in the PD region 27.
The x layer 32 is laminated. On the SiNx layer 32, a transparent electrode 44 connected to the source electrode 36 of the TFT region 26 described below is laminated. On the transparent electrode 44, an n + a-Si layer 37 and an ia-Si layer are formed. 38, p
A + a-Si layer 39 and the transparent electrode 40 are sequentially stacked to form a photodiode having a Pin structure.

A gate electrode 31 is formed on the support 25 in the TFT region 26, and a SiNx layer 32 extending from the PD region 27 is laminated on the gate electrode 31. Further, an a-Si layer 33 is laminated on the SiNx layer 32 on the TFT region 26, and a drain electrode 35 and a source electrode 36 are respectively formed on the a-Si layer 33 via an n + a-Si layer 34. There is. Further, on the drain electrode 35 and the source electrode 36,
The TFT region 26 and the PD region 27 are separated from each other by the first
The polyimide resin layer 41 is laminated.

On the first polyimide resin layer 41,
The metal electrode 42 so as to electrically connect the transparent electrodes 40 in the PD region 27 adjacent to the polyimide resin layer 41 to each other.
Is provided. Then, the second polyimide resin layer 43 is laminated on the transparent electrode 40 and the metal electrode 42, and on the second polyimide resin layer 43, the transparent protective film 30, the phosphor 29, and the light reflection layer 28. Are sequentially stacked.

In such a solid-state flat panel detector 5, the light reflecting layer 28 totally reflects visible light out of visible light and X-rays emitted from the outside and takes in only X-rays. Phosphor 2
9 converts the X-rays captured by the light reflection layer 28 into visible light and irradiates the PD area 27 with the visible light.

As a result, as described above, the charge corresponding to the visible light corresponding to the X-ray dose is stored in the storage capacitor provided in the PD region 27, and this charge is stored in the TFT.
The data is read out according to the on / off control of the TFT 12 in the area 26 and supplied to the monitor device or the like.

Next, the operation of the X-ray diagnostic apparatus of the first embodiment having such a configuration will be described.

First, when placing the patient on the bed 1, the operator operates the operation portion to support the lowering of the bed 1. When this support is made, the control unit controls the moving mechanism to control the bed 1 to descend. As a result, as shown in FIG. 1A, the solid-state flat panel detector 5 provided in the bed 1 descends together with the bed 1.

As described above, since the solid-state flat panel detector 5 is composed of a plurality of X-ray detecting elements, it is extremely thin and small. For this reason, it does not hinder the lowering of the bed 1, and as shown in FIG. 1 (a), it is possible to lower the bed 1 to the vicinity of the floor, so that the bed 1 of a physically handicapped patient can be lowered. It is possible to easily get on and off.

Next, when the operator places the patient on the bed 1 in this manner, the operator operates the operation portion to support the rise of the bed 1 and support the execution of imaging. When this support is made, the control unit controls the moving mechanism to control the bed 1.
Is controlled to be elevated, and then the X-ray tube 3 is controlled to be exposed. As a result, as shown in FIG. 1B, X-rays are emitted to a desired site of the patient placed on the bed 1. And this X
The X-ray image formed by the radiation of the rays is captured by the solid-state flat panel detector 5 and displayed on the monitor device.

As described above, in the X-ray diagnostic apparatus, since the bed 1 can be largely lowered, the X-ray tube 3 can be installed without providing a special mechanism for moving the X-ray tube 3 up and down.
A sufficient distance can be provided between the solid-state flat panel detector 5 and the solid-state flat panel detector 5. Therefore, it is possible to easily perform chest imaging or the like that requires the distance for imaging.

Further, the solid-state flat panel detector 5 is adapted to electrically read out the charges formed by the respective X-ray detecting elements in accordance with the X-ray image, and the electron beam scans like an image intensifier. Therefore, it is possible to obtain a clear display image without causing geometrical or magnetic distortion in the display image.

Further, since the detection surface of the solid-state flat panel detector 5 has a rectangular shape, a rectangular display image can be displayed on the display screen of the monitor device, and the display image has a shape suitable for observing a human body. Can be displayed. Therefore,
It can greatly contribute to the treatment plan by a doctor or the like.

Here, the X-ray diagnostic apparatus is capable of enlarging the display image by controlling the bed 1 to move up and down by the moving mechanism.

Specifically, the X-ray emitted from the X-ray tube 3 is a so-called cone beam in which the exposure range gradually expands as the distance from the focal point increases. For this reason,
As shown in FIGS. 1 (b) and 1 (c), the bed 1 is controlled to move up and down by a moving mechanism, so that the diameter A1 of the X-ray irradiation range at the center of the subject and the solid-state flat panel detector corresponding to the diameter A1. The ratio of the X-ray to the exposure range A2 on the image No. 5 changes, and the change in the ratio between the two is directly reflected in the enlargement ratio of the display image.

That is, the magnification of the display image is "M", the diameter of the X-ray exposure range at the center of the subject is "A1",
Assuming that the diameter of the X-ray irradiation range on the solid-state flat panel detector 5 corresponding to this is “A2”, the enlargement ratio M is M = A2 / A1.

This indicates that when the bed 1 is raised, the display image is enlarged because the diameter A1 of the X-ray exposure range at the center of the subject is reduced, and when the bed 1 is raised, the center of the subject is increased. It is shown that the display image is reduced because the diameter A1 of the X-ray exposure range is increased. Therefore,
The operator can obtain a display image with a desired enlargement ratio only by raising and lowering the bed 1, and can further facilitate the treatment plan by the doctor or the like.

Next, when the bed 1 is controlled up and down to change the enlargement ratio in this manner, there is a concern that X-rays may be exposed to a portion other than the image actually displayed as the display image. It For this reason, the X-ray diagnostic apparatus is provided with the X-ray diaphragm unit 7, and a control unit (not shown) controls this X-ray so that the X-ray is not exposed to a portion that is not reflected in the display image of the subject. The aperture 7 is controlled to be opened and closed to control the X-ray exposure range.

Specifically, the relationship between the ascending / descending state of the bed 1 and the X-ray exposure range in each ascending / descending state is detected in advance,
The detection result is stored as a table (opening / closing control table) as opening / closing control data indicating the opening / closing width of the X-ray diaphragm 7, for example. Therefore, when the bed 1 is controlled to move up and down, the control unit reads out the corresponding opening / closing control data from the opening / closing control table according to the lifting state of the bed 1.
The opening / closing width of the X-ray diaphragm 7 is controlled based on the opening / closing control data.

With this, even when the magnification is changed, it is possible to prevent the inconvenience that the X-rays are unnecessarily exposed to the portion which is not reflected in the display image of the subject. For this reason,
The exposure of the patient can be reduced, and the safety and reliability of the X-ray diagnostic apparatus can be improved.

Next, an X-ray diagnostic apparatus according to the second embodiment of the present invention will be described.

In the X-ray diagnostic apparatus according to the first embodiment described above, the solid-state flat panel detector 5 moves up and down together with the bed 1, but the X-ray diagnostic apparatus according to the second embodiment has a solid-state detector. The flat detector 5 can be raised and lowered independently of the bed 1.

Since the second embodiment differs from the first embodiment only in this point, the same operation as that of the first embodiment will be shown in the following description of the second embodiment. The same reference numerals are given to the parts, and detailed description thereof will be omitted.

That is, in the X-ray diagnostic apparatus according to the second embodiment, as shown in FIG. 4A, the solid-state flat panel detector 5 provided in the bed 1 is lifted and lowered separately from the bed 1. It has a drive unit 50.

Specifically, the lifting drive unit 50 is configured by fixing each piece of the pair of hinge-shaped lifting mechanisms 52 and connecting each other piece to the solid-state flat panel detector 5. The lifting mechanism 52 and the solid-state flat panel detector 5 are provided in each lifting mechanism 5
Bellows-shaped bellows cover 51 that expands and contracts according to the bending state of 2
The solid-state flat panel detector 5 is controlled to move up and down so as to prevent a danger such as clothes of a patient being caught.

Next, the operation of the X-ray diagnostic apparatus of the second embodiment having such a configuration will be described.

First, the operator lowers the bed 1 near the floor to place the patient on the bed in the same manner as described above, and then raises the bed 1 to a desired height to perform X-ray irradiation operation. . Thereby, as described above, a display image of a desired part of the patient can be obtained on the display screen of the monitor device.

Here, when the operator who views this display image wants to change the enlargement ratio of the display image, he or she operates the operation unit to support the enlargement or reduction of the display image. Each lifting mechanism 52
When the operator supports the enlargement of the display image, the solid-state flat panel detector 5 is controlled to descend to move away from the subject,
When the operator supports the reduction of the display image, the solid-state flat panel detector 5 is controlled to move up to approach the subject.

Specifically, since the X-rays emitted from the X-ray tube 3 are so-called cone beams, the spread of the X-rays increases as the distance from the focal point of the X-ray tube 3 increases.
As shown in (a), the X-ray having the A1 diameter spread at the center of the human body has a larger A2 diameter spread than the A1 diameter spread on the detection surface of the solid-state flat panel detector 5. .

In this state, when the elevating mechanism 52 controls the raising of the solid-state flat panel detector 5, as shown in FIG. 4B, the solid-state flat panel detector 5 causes the X-ray cone beam to converge (X-ray direction). Since the X-ray having a diameter spread of B1 (= A1) at the center of the human body is moved in the direction of approaching the focal point of the tube 3), the X-ray having the B1 (= A1) diameter spread on the detection surface of the solid-state flat panel detector 5 is
The width of the diameter of B2 is narrower than that of the diameter of 2.

Therefore, although the X-ray exposure position on the human body does not change (A1, B1), the detection range of this X-ray image is narrowed by the rising control of the solid-state flat panel detector 5.
The display image is reduced and displayed.

On the contrary, the solid-state flat panel detector 5 is shown in FIG.
When the descending control is performed from the position shown in FIG. 4, the X-ray image is detected at the position of the diameter of A2 where the cone beam of X-rays is wider than the diameter of B2 as shown in FIG. It will be enlarged and displayed.

Such an enlargement ratio can be defined by the following equation.

That is, since the X-ray tube 3 is fixed as described above, the distance "L2" from (the focal point of) the X-ray tube 3 to the center of the patient's body as shown in FIG. It is constant unless the bed 1 is controlled to move up and down. Then, the distance “L1” from the X-ray tube 3 to the solid-state flat panel detector 5 is changed by the elevation control of the solid-state flat panel detector 5. Therefore, the enlargement ratio “M” is M = L1 / L2 (L2 is constant).

As described above, the X-ray diagnostic apparatus according to the second embodiment can change the enlargement ratio of the display image by controlling the elevation of the solid-state flat panel detector 5 by each elevating mechanism 52. Therefore, for example, when it is desired to enlarge and display the affected area, a display image with a desired enlargement ratio can be obtained without controlling the raising and lowering of the bed 1, which can greatly contribute to accurate and rapid diagnostic treatment. The same effect as that of the X-ray diagnostic apparatus according to the first embodiment can be obtained.

Also in the X-ray CT apparatus according to the second embodiment, the enlargement ratio is changed by controlling the bed 1 to move up and down like the X-ray diagnostic apparatus according to the first embodiment. be able to. Of course, the X-ray diaphragm unit 7 is controlled to be opened / closed by the control unit in response to the elevating control of the bed 1 or the elevating control of the solid-state flat panel detector 5 to reduce the radiation exposure to the subject. .

Next, an X-ray diagnostic apparatus according to the third embodiment of the present invention will be described.

In the X-ray diagnostic apparatus according to the second embodiment described above, the solid-state flat panel detector 5 is used with the X-ray tube 3 fixed.
However, the X-ray diagnostic apparatus according to the third embodiment controls the X-ray tube 3 up and down together with the up-and-down control of the solid-state flat panel detector 5. Detector 5
The enlargement ratio of the display image can be changed while maintaining the distance between them.

Since the third embodiment is different from the second embodiment only in this point, the following description of the third embodiment shows the same operation as that of the second embodiment. The same reference numerals are given to the parts, and detailed description thereof will be omitted.

That is, in the X-ray diagnostic apparatus according to the third embodiment, as shown in FIG. 5A, the X-ray tube lifting mechanism for controlling the X-ray tube 3 to move up and down along the X-ray tube support 4. have.

In the X-ray diagnostic apparatus according to the third embodiment, the operator can support the change of the magnification of the display image while maintaining the distance between the X-ray tube 3 and the solid-state flat panel detector 5. Then, the X-ray tube lifting mechanism is linked to the lifting control of each lifting mechanism 52 of the solid-state flat panel detector 5 so as to maintain the distance between the X-ray tube 3 and the solid-state flat panel detector 5. The X-ray tube 3 is vertically controlled.

In the X-ray diagnostic apparatus according to the second embodiment described above, since the X-ray tube 3 is fixed, the enlargement ratio is reduced by controlling the solid-state flat panel detector 5 to descend, and the solid-plane flat panel detector 5 is reduced. Although the enlargement ratio is increased by controlling the detector 5 to move up, the X-ray diagnostic apparatus according to the third embodiment of the present invention controls the X-ray tube 3 to move up and down in response to the moving up and down of the solid-state flat panel detector 5. Therefore, the enlargement ratio is increased by lowering the X-ray tube 3 and the solid-state flat panel detector 5, and is decreased by controlling the X-ray tube 3 and the solid-state flat panel detector 5 ascending. ing.

That is, for example, as shown in FIG. 5A, an X-ray cone beam having a diameter of A1 at the center of the human body and a diameter of A2 at the detection surface of the solid-state flat panel detector 5 is detected by solid-state flat panel detection. When the descent control of the X-ray tube 5 is performed, the X-ray tube 3 is descent controlled so as to maintain the initial distance between the X-ray tube 3 and the solid-state flat panel detector 5. The center of the human body is positioned, and as shown in FIG. 5 (b), the diameter on the detection surface of the solid-state flat panel detector 5 is the same as the diameter of B2 (= A2). It will be narrowed to the diameter of B1.

This means that the exposure range of X-rays to the human body is narrowed, but this X-ray image is detected in the same range as before the narrowing, so the display image is enlarged and displayed. .

On the contrary, when the X-ray tube 3 and the solid-state flat panel detector 5 are controlled to be raised from the position shown in FIG. 5B, the center of the human body is located at the position where the cone beam of X-rays spreads. As shown in FIG. 5A, the diameter on the detection surface of the solid-state flat panel detector 5 is the same as the diameter of A2 (= B2), but the diameter of the center of the human body expands to the diameter of A1.

This means that the X-ray exposure range to the human body is widened, but this X-ray image is detected in the same range as before the spread, so the display image is displayed in a reduced size. .

Such enlargement ratio can be defined by the following formula.

In this case, since the X-ray tube 3 is controlled to move up and down according to the lifting control of the solid-state flat panel detector 5, the distance "L1" between the X-ray tube 3 and the solid-state flat panel detector 5 is always constant. Yes,
Distance "L2" between (focus of) X-ray tube 3 and the center of the patient
Only will change. Therefore, the enlargement ratio "M"
Becomes M = L1 / L2 (L1 is constant).

As described above, in the X-ray diagnostic apparatus according to the third embodiment, when the elevating mechanism 52 controls the elevation of the solid-state flat panel detector 5, the X-ray tube 3 and the solid-state flat panel detector 5 are connected to each other. By controlling the X-ray tube 3 to move up and down so as to maintain the distance between them, the magnification of the display image can be changed. Therefore, the same effects as those of the X-ray diagnostic apparatus according to the first and second embodiments described above can be obtained.

Also in the X-ray CT apparatus according to the third embodiment, the enlargement ratio is changed by controlling the bed 1 to move up and down like the X-ray diagnostic apparatus according to the first embodiment. be able to. Then, the control unit controls the opening and closing of the X-ray diaphragm unit 7 in response to the raising and lowering control of the bed 1 or the raising and lowering control of the solid-state flat panel detector 5 as a matter of course. is there.

Next, an X-ray diagnostic apparatus according to the fourth embodiment of the present invention will be described.

In the X-ray diagnostic apparatus according to the third embodiment described above, the X-ray tube 3 is controlled to be vertically moved up and down with respect to the floor, but the X-ray according to the fourth embodiment is used. The diagnostic apparatus is capable of obliquely irradiating the patient with X-rays by controlling the rotation of the X-ray tube support 4 to enable oblique-incidence imaging.

The fourth embodiment differs from the third embodiment only in this point, and therefore, in the following description of the fourth embodiment, the same operation as that of the third embodiment will be shown. The same reference numerals are given to the parts, and detailed description thereof will be omitted.

That is, the X-ray diagnostic apparatus according to the fourth embodiment supports the X-ray tube 3 so as to vertically irradiate the patient with X-rays as shown in FIG. 6A. The X-ray tube support 4 is provided with a rotation control mechanism for controlling the rotation so that X-rays are obliquely exposed to the patient.

In the X-ray diagnostic apparatus according to the fourth embodiment as described above, when the operator sets the X-ray exposure angle when performing oblique-incidence radiography, the rotation control mechanism is indicated by the arrow in FIG. 6A. As shown, the X-ray tube support 4 (and the X-ray tube 3) is rotationally controlled.

More specifically, the X-ray exposure angle is based on the exposure angle at which the X-ray is emitted vertically to the patient.
For example, the exposure angle can be set to about ± 80 degrees. When this exposure angle is designated by the operator, the rotation control mechanism controls the rotation of the X-ray tube support column 4. At this time, each lifting mechanism 52 of the lifting drive unit 50 is controlled by the operation shown in FIG.
As shown in (b), the position of the solid-state flat panel detector 5 is controlled so that the X-rays emitted at this exposure angle are detected substantially vertically.

As a result, oblique photographing can be performed, and a tomographic image of the body can be obtained. In addition, FIG.
As shown in (a), when the X-ray is vertically irradiated to the patient, the diameter of the cone beam of the X-ray at the center of the human body is A.
On the other hand, since the cone beam of X-rays is obliquely exposed to the human body at the time of oblique incidence, the diameter at the center of the human body is set to A as shown in FIG. 6B. The diameter of B can be made larger than the diameter of B. By detecting this X-ray vertically by the solid-state flat panel detector 5, X
In addition to being able to take a large field of view at the same enlargement ratio as when a line is exposed, the same effect as each of the above-described embodiments can be obtained.

In the X-ray CT apparatus according to the fourth embodiment, the enlargement ratio is changed by controlling the bed 1 to move up and down like the X-ray diagnostic apparatus according to the first embodiment. be able to. Then, the control unit controls the opening and closing of the X-ray diaphragm unit 7 in response to the raising and lowering control of the bed 1 or the raising and lowering control of the solid-state flat panel detector 5 and the X-ray tube 3 to reduce the exposure to the subject. Of course, it will be done.

Finally, in the above description of each embodiment,
Although the detection surface of the solid-state flat panel detector 5 has a rectangular shape, it may have an arbitrary shape such as a circular shape. Further, the solid-state flat panel detector 5 is of a charge read type that accumulates and reads out charges according to the dose of X-rays, which forms a voltage according to the dose of X-rays and May be a voltage read type. Although the patient is placed on the bed 1 and the image is taken, the patient may be taken in an upright position. Furthermore, the solid-state flat panel detector 5 once converts the exposed X-rays into visible light,
We decided to use a so-called indirect conversion type solid-state flat panel detector that accumulates and reads charges corresponding to the amount of visible light in the photodiode, but this does not convert the exposed X-rays into visible light. Alternatively, a direct conversion type solid-state flat panel detector that directly converts electric charges may be used.

The above-described embodiments are only examples of the present invention. Therefore, the present invention is not limited to each of the above-described embodiments, and various modifications can be made according to the design and the like as long as they do not deviate from the technical idea of the present invention. Of course.

[0091]

The X-ray diagnostic apparatus according to the present invention can significantly lower the bed. Therefore, it is possible to easily get on and off the patient's bed. Also,
It is possible to maintain a sufficient distance between the X-ray generation means and the solid-state flat panel detector, and it is possible to easily perform chest imaging or the like that requires the distance.

Further, since the existing mechanism for raising and lowering the bed can be used as it is to enable the bed to be lowered significantly, it is not necessary to provide a special new mechanism for this purpose, and the structure can be simplified and Cost reduction can be achieved.

Further, since the solid-state flat panel detector is connected to the bed so that the position can be controlled independently of the vertical movement of the bed, by controlling the position of the solid-state flat panel detector, tomography or display image A change in magnification can be realized.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an X-ray diagnostic apparatus according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a solid-state flat panel detector provided in the X-ray diagnostic apparatus according to the first embodiment.

FIG. 3 is a partial cross-sectional view of the solid-state flat panel detector.

FIG. 4 is a schematic diagram of an X-ray diagnostic apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic diagram of a modified example of the X-ray diagnostic apparatus according to the second embodiment.

FIG. 6 is a diagram for explaining oblique imaging in the X-ray diagnostic apparatus according to the second embodiment.

FIG. 7 is a schematic diagram of a conventional over-tube type X-ray diagnostic apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bed, 2 ... Bed support, 3 ... X-ray tube, 4 ... X-ray tube support, 6 ... Support stand 5 ... Solid plane detector, 50 ... Elevating drive part 51 of solid plane detector ... Bellows cover, 52 ... Lifting mechanism

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-8-126640 (JP, A) JP-A-8-47491 (JP, A) JP-A-7-51258 (JP, A) JP-A-4- 341244 (JP, A) JP-A-58-16227 (JP, A) JP-A-10-57360 (JP, A) Actual development Shou- 50-14364 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61B 6/00-6/14

Claims (5)

(57) [Claims] 1. A couch on which a subject is placed, a couch support for supporting the couch so that the couch can be raised and lowered, and an X-ray that radiates X-rays to the subject placed on the couch.
X-ray tube, X-ray tube support means for supporting the X-ray tube, and X-ray tube for controlling rotation of the X-ray tube support means so that X-rays are obliquely exposed to the subject. A support control means and a solid body that is connected to the bed so that the position of the bed can be controlled independently of the vertical movement of the bed and that detects transmitted X-rays of the subject by a plurality of solid-state detection elements that are two-dimensionally arranged. A solid-state flat panel detector, wherein the solid-state flat panel detector has an X-ray detection surface of the solid-state flat panel detector that moves along with the rotation of the X-ray tube supporting unit by the X-ray tube supporting control unit. An X-ray diagnostic apparatus characterized in that its position is controlled so as to face the radiation exposure surface. 2. A couch on which a subject is placed, a couch support for supporting the couch so that the couch can be raised and lowered, and an X-ray that radiates X-rays to the subject placed on the couch.
X-ray tube, X-ray tube support means for supporting the X-ray tube, and X-ray tube for controlling rotation of the X-ray tube support means so that X-rays are obliquely exposed to the subject. A support control means and a solid body which is connected to the bed so as to be position-controllable independently of vertical movement of the bed, and which detects a transmitted X-ray of the subject by a plurality of solid-state detection elements arranged two-dimensionally. An X-ray diagnostic apparatus comprising: a flat panel detector; and a bellows-shaped cover provided below the bed and covering the solid-state flat panel detector. 3. An instruction means for instructing a change of a magnification of an image to be displayed, the elevation of the bed and / or the position of the solid-state flat panel detector being controlled according to the instruction by the instruction means. The X-ray diagnostic apparatus according to claim 1, wherein: 4. The X-ray tube is controlled so as not to be exposed to X-rays on the part of the subject that is not reflected in the X-ray image according to the movement control of the bed and / or the position control of the solid-state flat panel detector. 4. The X according to claim 1, further comprising an X-ray diaphragm unit that controls an X-ray exposure range of the X-ray.
Line diagnostic device. 5. The X-ray diagnostic apparatus according to claim 1, wherein an X-ray detection surface of the solid-state flat panel detector has a rectangular shape.