JPH05292402A - X-ray diagnostic device - Google Patents

Abstract

PURPOSE:To surely performing photographing with proper density and further to intensity photograph a desired part to be observed with proper density in the case of performing photographing while designating a lighting field to a see-through image. CONSTITUTION:A fiber diode detector 9 to be designated a lighting field S can be moved backward and forward or to right and left by driving means (a horizontal moving motor 25 and a vertical moving rotor 31), and a moving switch 34 to control this driving control means is provided integrally with a top panel slide/spot moving handle 35. The moved lighting field always follows the position, and a lighting field mark 40 is displayed on a monitor. Thus, since the lighting field can be always designated at the optimum position with a simple operating method, the picture with the proper density can be photographed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention displays on a display means a fluoroscopic image of X-rays transmitted through a subject, and the image is used for positioning of the radiograph, and at the time of radiographing, the X-ray after passing through the subject is taken.
The present invention relates to an X-ray diagnostic apparatus that controls the density of a captured image to an appropriate density based on the X-ray dose or the light amount obtained from a daylighting field specified in a part of a ray cone or an output image of an image intensifier.

[0002]

2. Description of the Related Art A fluoroscopic image obtained by irradiating a subject with X-rays from an X-ray tube is displayed on display means such as a monitor,
This fluoroscopic image is used for positioning of the radiography and at the time of radiography, the radiography is performed within the X-ray cone after passing through the subject or the I.D. I. An X-ray diagnostic apparatus is known in which a lighting field is specified in a part of an output image of (image intensifier) and the density of a captured image is controlled to an appropriate density based on the amount of light obtained from this. .. When a diagnosis for the stomach or the large intestine is performed by such a diagnostic device, a contrast examination using a contrast agent such as barium is widely performed in order to make an efficient diagnosis.

By the way, when performing such a contrast examination,
The exposed X-rays hardly pass through a portion where barium is abundant, but on the other hand, there is a property that a large amount passes through the lung field and gas portion. The control method of the imaging density is to continue the X-ray exposure until the total of the X-ray doses detected in the light collection field reaches the reference value. For this reason, for example, when the barium portion covers half of the lighting field, the X-ray dose detected in the other half is compared with the reference value, the time to reach the reference value is extended, and the X-ray exposure time is lengthened. The concentration of) will increase. Further, the reverse phenomenon occurs due to the influence of direct ray incident on the image passing means for recording a film or the like without passing through the subject. As a result, a doctor or a technician cannot obtain a photograph with an appropriate density that he or she wants to observe, resulting in a decrease in diagnosis efficiency.

In FIG. 9, the lighting field is I.D. I. This is to explain this situation when it is located in the output image of X-rays. When shooting, the X-rays that have passed through the subject and become image information reach the X-ray film and are recorded as a photograph. Since the penetrating power of I.P. I. To reach. Therefore, I. I. An image similar to the captured image is displayed on the output surface. I. I. The output image 43 is displayed on the I.D. I. A circular light-collecting field S is designated in advance in the substantially central portion of the output surface 41 of (1), and imaging is performed based on the amount of light obtained from the region of this light-collecting field S. Here, the amount of light along a horizontal scanning line L in the lighting field is as shown in FIG.
In the barium-covered portion indicated by diagonal lines, it is almost zero as in P2, while it is large as in P1 in other portions. Therefore, as described above, it is possible to obtain a photograph having variations in density.

Therefore, in the past, measures have been provided to eliminate such adverse effects. This measure is roughly classified into: (1) The area of the barium coating in the designated lighting field or the presence or absence of direct ray incidence is determined from the perspective image for positioning immediately before shooting, and based on that, detected in the lighting field at the time of shooting. Means to correct the reference value to compare with the total X-ray dose, and (2) Specify multiple light-collecting fields and average the X-ray doses detected in each light-collecting field to reach the reference value. X-ray irradiation is continued until the density of the entire photograph is less affected by the partial barium portion or the direct ray incident portion.

FIG. 11 shows the first proposal of the former (1). I. I. An image similar to the captured image output to I. I. After being taken out by the output lens 44, this optical signal output is input to the photomultiplier 10 via the mirror 45 and the amount of light is detected. Before this photographing operation, fluoroscopy for positioning of photographing is performed as described above. The X-ray is exposed to the subject even during fluoroscopy. What is different from photography is that the X-ray film and other photography components are retracted outside the X-ray cone.
Only the members (for example, grids) necessary for fluoroscopy are transmitted and the I.V. I. To the X-rays and X-rays weaker than the X-rays are continuously exposed for a long time. Therefore, the I.D.
I. A clear image can be obtained for a long time on the output surface of the. This is photographed by the TV camera 15 and provided as a perspective image on a monitor placed in front of the inspector. The area correction circuit 13 takes out only the signal in the range corresponding to the lighting field in the video signal of the fluoroscopic image immediately before photographing, and estimates the area of the barium-covered portion in the lighting field or the presence of direct ray incidence from the video signal level, Determine the correction value. This is added to the automatic exposure control device (AEC) 11 to correct the reference value, and the light amount information detected by the photomultiplier 10 is added as described above at the time of immediately after shooting, and the total reaches the corrected reference value. Then, an X-ray cutoff signal is applied to the X-ray controller 12 to cut off the X-rays. As a result, the effects of barium covering the lighting field and direct rays incident on the lighting field are reduced.

FIG. 12 shows the second proposal of the former (1), in which the light quantity is detected by the photomultiplier 10 by the fiber photodetector 9 provided in front of the film 6 arranged in the spot frame. The outputs of the photomultiplier 10 and the area correction circuit 13 are added to the AEC 11. The fiber photo detector 9 is a device for illuminating a thin fluorescent paper with X-rays and outputting the amount of light.

FIG. 13 shows the first proposal of the latter (2). I. I. The optical signal output extracted by the output lens 44 is input to a plurality of photodiodes 46 arranged, and as shown in FIG. 14, the light amount is detected from the lighting fields of the multiple points P1 to Pn, and this output is AEC11. In addition, the average of multiple points is taken to reduce the influence of barium coating or the like. In each figure, 8 is a grid and 7 is a contact plate.

In each of the conventional means, the lighting field S or P1 is used.
The position of ~ Pn is fixed, and the lighting field S or P1 ~ Pn
Since the outline of is not displayed on the monitor which is a means for displaying a perspective image, the user cannot check it.

[0010]

The measures proposed by the conventional X-ray diagnostic apparatus have the following problems, respectively.

First, in each means for estimating the area or the presence / absence of direct ray incidence in (1), the conversion process of information is different from that of the photographed image, and it is based on the estimation from the perspective image in which the information collection time is deviated. Since the correction is performed in advance, the correction tends to be under-corrected or over-corrected, and it becomes difficult to stably obtain an appropriate photographing density. Further, in the multi-lighting field of (2), since it is necessary to prepare a plurality of detectors, it takes a great deal of effort to match each characteristic, and if this is insufficient, the same adverse effect as described above occurs.

Furthermore, the harmful effect of the means (1) can be alleviated to some extent if the examiner positions the subject so that the barium portion does not excessively cover the lighting field, but the position of the lighting field S is not displayed on the monitor. Therefore, the inspector must always image this position, requires skill, and is not certain. Furthermore, both (1) and (2) have a fixed light field, so the size of the passing image recording means such as film
The position of the subject cannot be displaced any further, but there is no means when the light-collecting field is largely covered by the barium portion. In addition, it is impossible for the inspector to consciously adjust the desired part to the proper concentration.

The present invention has been made in consideration of the above problems, and an X-ray that allows an inspector to reliably take an image at an appropriate density and further allow the inspector to consciously take an image at an appropriate density. It is an object of the present invention to provide a diagnostic device.

[0014]

In order to achieve the above object, the present invention displays a fluoroscopic image of X-rays transmitted through a subject on a display means, and this image is used for positioning of the radiographing and at the time of radiographing the subject. In an X-ray diagnostic apparatus for controlling the density of a captured image to an appropriate density based on the X-ray dose or the light amount obtained from a designated lighting field in a part of the output image of the image intensifier in the X-ray cone after transmission, The X-ray detecting means for designating the light-collecting field, the driving means capable of moving the X-ray detecting means two-dimensionally in the vertical and horizontal directions in the light-collecting field plane, and the coordinate position of the light-collecting field moved together with the driving means are set. It is characterized by comprising coordinate detecting means for detecting and display control means for displaying the position of the lighting field on the display means based on the detected coordinate position.

[0015]

The X-ray detecting means for designating the lighting field is configured to be movable in the vertical and horizontal directions in the lighting field plane by the driving means.
Since the moving position of the lighting field is always followed and displayed on the display means, the user can always confirm and select the optimum position of the lighting field. Therefore, the user can take a photographed image at an appropriate density. Further, as described above, the operation for moving the position of the light collecting field to the optimum position is to integrally incorporate the switch for operating the movement on the operation panel for operating the X-ray fluoroscopic imaging table on which the examiner puts the subject. This can be done easily.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an X-ray diagnostic apparatus according to the present invention. Reference numeral 1 is an X-ray tube for irradiating a subject 3 lying on a top plate 2 with X-rays and seeing through the X-ray. The image will be described later on monitor 1
It is for displaying on the display 7, positioning for shooting, and shooting a shot image. An operation panel 4 is provided with various switches for performing necessary control operations including control of the top plate 2.

Reference numeral 5 denotes a spot frame arranged behind the top plate 2, and as shown in FIG. 2, a contact plate 7 for holding a film 6 on which an X-ray image transmitted through the subject 3 is imaged and scattered rays. A grid 8 for removing is built in. Further, a fiber photo detector 9 for designating a lighting field is provided between the film 6 and the grid 8. In this embodiment, this lighting field is configured to be movable in the vertical direction (front-back direction) and left-right direction within the lighting field plane by driving the fiber photodetector 9.

As shown in FIG. 3, this fiber photo detector 9 is a fluorescent paper 9A which emits light when irradiated with X-rays.
And a mask 9B for covering the lower surface excluding this for designating the lighting field S, and an optical fiber 9C for detecting the amount of light from the lighting field S. Reference numeral 10 is a photomultiplier that converts the amount of light detected by the fiber photodetector 9 into an electric signal, 11 is an automatic exposure controller (AEC), and 12 is an X-ray controller controlled by this AEC 11. Reference numeral 14 denotes I. 14 which displays a fluoroscopic image based on the X-ray dose of the subject. I. , 15 is a TV camera that captures this perspective image, 16 is a camera controller, and 17 is a CR that is controlled by this camera controller 16 and that displays a perspective image.
A monitor including a T display and the like.

FIG. 4 shows a driving mechanism for the fiber photo detector 9. The driving mechanism 18 includes a vertically movable frame 19 which is movable in the vertical direction, and a facing surface 19A of the vertically movable frame 19.
A pair of hollow shafts 20A provided by inserting the
20B, a belt 2 that is wound between the pair of shafts 20A and 20B and holds the fiber photodetector 9.
1. The timing belt 23 wound between the timing pulleys 22A and 22B provided on the shafts 20A and 20B, respectively.

The inside of one hollow shaft 20A serves as a guide capable of a combined motion of rotation and slide.
A pair of thin guide shafts 20C are inserted inside this. The other hollow shaft 20B is a ball spline, and one end of a guide 20D that is inserted through the inside is provided with a left-right movement motor 25 and an encoder 26 for detecting left and right positions via a reduction gear 24. .. That is, the shaft 20B is slidable in the axial direction and the rotation is transmitted. When the left-right motion motor 25 rotates, this rotational force is transmitted to the hollow shaft 20B via the ball spline and further transmitted to the hollow shaft 20A via the timing pulley 22B, the timing belt 23, and the timing pulley 22A. The hollow shafts 20A and 20B are rotated in the same direction. As a result, the fiber photodetector 9 is moved laterally via the belt 21, so that the daylight can be laterally moved.

Further, a vertical movement means 28 for converting a rotational movement into a linear movement, for example, Laurix (trade name), is provided on the orthogonal surface 19B of the vertical movement frame 19 opposite to the facing surface 19A. A vertical movement shaft 29 is inserted through the vertical movement shaft 29. A vertical movement motor 31 and an encoder 32 for detecting the vertical position are provided at one end of the vertical movement shaft 29 via a speed reducer 30.
Is provided. When the vertical movement motor 31 rotates,
This rotational force is transmitted to the vertical movement shaft 29, and further converted into a linear movement by the vertical movement means 28, whereby the vertical movement frame 19 is moved in the vertical direction orthogonal to the horizontal movement. As a result, the fiber photo detector 9 moves up and down together with the up-and-down moving frame 19, so that the up-and-down movement of the lighting field becomes possible.

The vertical moving means 28 may be a lead screw or the like. Further, instead of the ball spline, a spline is further used, and the timing pulleys 22A, 2
2B, a sprocket, a chain or the like can be used instead of the timing belt 23.

FIG. 5 shows an example of mounting a detector moving switch 34 for controlling the movement of the light collecting field S on the fiber photodetector 9 in FIG. 4 in the front-rear and left-right directions. 35 shows a structure provided integrally with 35. The handle 35 is provided with various switches so that the operator can operate the positioning of the subject and the generation of radiographic X-rays with one hand. For example, the radiographic X-ray switch 3 can be used.
6, a top plate up / down / spot up / down changeover switch 37, a speed changeover dial 38 and the like are provided.

FIG. 6 shows a structure for displaying on a monitor a lighting field S which is controlled by the detector switch 34 so as to be movable back and forth and left and right. The respective detection signals output from the encoder 26 for detecting the lateral movement position and the encoder 32 for detecting the vertical movement position are input to the lighting field position calculation circuit 39. The current position is calculated and the result is output to the camera controller 16 as coordinate data. The camera controller 16 displays the perspective image 43 based on the signal from the TV camera 15 on the monitor 17, and superimposes the lighting field mark 40 having the same shape and size as the actual lighting field S on the perspective image 43. To display. The switch 34
As the lighting field S moves in the front-rear, left-right direction by tilting the handle 35 while pressing, the mark 40 on the monitor 17 also moves as the position is detected by the encoders 26 and 32. It will be. Next, the operation of this embodiment will be described.

A perspective image 43 of a subject injected with a contrast agent such as barium is displayed on the monitor 17 as shown in FIG. 7, and the current light field mark 40 is displayed as a solid line in the figure. And At this position, most of the mark 40 is on the barium-covered portion (hatched portion) of the perspective image 43, so if shooting is performed with the lighting field specified at this position, the shooting time will increase as in the conventional case. A photograph of proper density cannot be obtained.

Therefore, as shown in FIG. 8, the operator first presses the detector movement switch 34 as shown by arrow A,
By operating the top plate slide / spot vertical movement handle 35 to tilt it forward as shown by arrow B, the lighting field mark 40 in FIG. 7 moves upward as shown by the broken line. When the lighting field mark 40 moves to the optimum position where the barium coating part is avoided and there is no direct incidence of rays, the operator stops the operation of the handle 35 to fix the lighting field to this position.

Subsequently, the switch 37 is pressed to start photographing, and a photographed image controlled to have an appropriate density is photographed on the basis of the X-ray dose or light amount obtained from the lighting field. Furthermore, since the density of the lighting field is controlled to be appropriate,
As mentioned above, it is possible not only to avoid barium coating, but also to move the lighting field to the part you want to see consciously.

Thus, according to this embodiment, the perspective image 43
Is displayed on the monitor 17 before the start of shooting,
While checking the lighting field mark 40 at the current position on the monitor 17, the operator can move the lighting field to a position where he / she wants to avoid the barium-covered part or a desired position, so that the shooting can be started at the optimum position. it can. Therefore, a user such as a doctor or a technician can always obtain a photograph with an appropriate density, so that the diagnosis efficiency can be improved. Moreover, the operation of moving the lighting field to an arbitrary position can be easily performed because the top plate slide / spot vertical movement handle can be used. Further, by displaying the mark of the lighting field which is not displayed on the monitor 17 in the related art, the user is relieved from the troublesome operation of positioning the subject while imagining the position of the lighting field, so that an extra burden is imposed. You will be able to concentrate on the original diagnosis without participating.

If the display of the daylighting field mark 40 on the monitor 17 has a diagnostic problem, this display may be deleted. This can be easily realized by providing a lighting field mark erasing switch on the operation panel 4. In this way, when the lighting field mark is erased, the position of the lighting field is automatically returned to the central portion of the display surface, so that the operation can be performed with the same feeling as that of the conventional device.

In the embodiment, the operation of moving the lighting field in the vertical direction has been described, but the present invention is not limited to this, and it can be moved in any direction. Fiber photo detector 9
Is not limited to the case of being placed in the spot frame 5, but by providing a moving means and a position detecting means, the I.D. I. It is applicable even when the detector is arranged on the output side.

[0032]

As described above, according to the present invention, since the lighting field can be moved in any direction while displaying the lighting field mark on the monitor, the user can move to a position where he / she wants to avoid the barium-covered portion or the like. By doing so, it is possible to take a photograph of an appropriate density, and it can be realized by a simple switch operation.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an X-ray diagnostic apparatus of the present invention.

FIG. 2 is a schematic diagram showing a spot frame used in the apparatus of this embodiment.

FIG. 3 is a schematic diagram showing a fiber photodetector used in the apparatus of this embodiment.

FIG. 4 is a configuration diagram showing a drive mechanism of a fiber photodetector used in the apparatus of this embodiment.

FIG. 5 is an external view showing a top plate slide / spot vertical movement handle used in the apparatus of this embodiment.

FIG. 6 is a configuration diagram showing a signal processing circuit used in the device of this embodiment.

FIG. 7 is a display example of a perspective image performed using the apparatus of this embodiment.

FIG. 8 is an explanatory diagram of an operating method of a top plate slide / spot vertical movement handle used in the apparatus of this embodiment.

FIG. 9 is a display example of a perspective image for explaining a conventional defect.

FIG. 10 is a characteristic diagram illustrating a conventional defect.

FIG. 11 is a configuration diagram showing a conventional device.

FIG. 12 is a configuration diagram showing another example of a conventional device.

FIG. 13 is a configuration diagram showing another example of a conventional device.

14 is an explanatory diagram showing the operating principle of the conventional device of FIG.

[Explanation of symbols]

 5 Spot frame 6 X-ray film 9 Fiber photo detector 10 Photomal 14 I. I. (Image intensifier) 15 TV camera 16 Camera controller 17 Monitor 18 Fiber photo detector drive mechanism 19 Vertical movement frame 26, 32 Encoder 34 Detector movement switch 35 Top plate slide / spot vertical movement handle 39 Lighting field position calculation circuit 40 Lighting field mark

Claims (1)

[Claims] 1. A fluoroscopic image of X-rays transmitted through a subject is displayed on a display unit, and the image is used for positioning of the image. At the time of image capturing, the image is transmitted within the X-ray cone or the output of an image intensifier. In an X-ray diagnostic apparatus that controls the density of a captured image to an appropriate density based on the X-ray dose or the light amount obtained from a designated lighting field in a part of the image, an X-ray detection unit for designating the lighting field. The driving means that can move the X-ray detecting means two-dimensionally in the vertical and horizontal directions in the lighting field plane, the coordinate detecting means that detects the coordinate position of the lighting field that is moved together with the driving means, and the detected coordinate position. An X-ray diagnostic apparatus comprising: a display control unit that displays the position of the lighting field on the display unit.