JPS63238854A - X-ray television tomographic imaging apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves relatively moving an X-ray tube device and an X-ray detector with a subject in between, and emitting X-rays to the subject. The present invention relates to an X-ray television tomography apparatus that captures and displays tomographic images of tomographic planes within a subject, and particularly relates to an X-ray television tomography apparatus that can perform IUA of an image of an affected area that overlaps with a bone or the like and is shaded.

[Conventional technology]

As shown in FIG. 3, a conventional X-ray television tomography apparatus has an X-ray tube device 1 which is placed opposite the X-ray tube device 1 with a subject 2 in between, and converts transmitted X-ray images into visible light. an X-ray detector 3 that converts the output optical image into an electric signal, a television camera 4 that takes this optical image and converts it into an electric signal, and a television camera 4 that controls the television camera 4 and inputs the electric signal from the television camera 4 to generate a video signal. a memory device 6 that converts the video signal from the television camera controller 5 into a digital quantity, records projection data, reads out the same, converts it into an analog signal, and reproduces the video signal; A television monitor 7 for displaying the video signal from the memory device 6 was included. In addition,
In FIG. 3, reference numeral 8 is a table on which the subject 2 is placed, and reference numeral 9 is a light distributor that distributes the output light from the X-ray detector 3 to the television camera 4 and others. and,
A plurality of images are photographed while changing the relative positions of the X-ray tube device 1 and the X-ray detector 3 in the directions of arrows A and B, and each projection data at each photographing position recorded in the memory device 6 is loaded. Shift 1 is added according to the height from the cross section (the plane including the center of relative movement between the X-ray tube device 1 and the X-ray detector 3), and a tomographic image of a certain tomographic plane in the subject 2 is calculated. , was displayed.

[Problem that the invention seeks to solve]

However, in such an X-ray television tomography apparatus, the obtained tomographic image is a planar image obtained by shifting and adding each projection data for a certain tomographic plane.
As shown in the figure, like normal X-ray fluoroscopic images and X-ray photographs, only a transmitted image from one direction could be seen. Therefore, as shown with diagonal lines in Figure 4, if a bone part overlaps with the affected area, or if the heart or diaphragm overlaps with the affected area, the image of the affected area hidden by the overlap will be almost invisible. Although it is not visible, it is difficult to recognize the image of the affected area by observing minute contrast differences between images of the affected area, such as bones, and the like. In addition, in the case of item 1, by setting the tomographic plane at the height where the affected area is located and adding it to Schiff 1, it is possible to display and observe a tomographic image that includes the affected area, but especially If the overlapping distance between a bone or the like and the affected area is close, the bone or the like remains as an obstruction shadow even after shift addition, and the image of the affected area may not be visible after all.

For these reasons, in image diagnosis of the subject 2, etc., the image of the target affected area cannot be sufficiently observed with tiJ1, and good diagnostic information may not be obtained. Therefore,
In some cases, the clinical value of the X-ray television tomography system could not be fully demonstrated.

Therefore, an object of the present invention is to provide an X-ray television tomography apparatus that can solve these problems.

[Means for solving problems]

Means of the present invention for solving the above problems includes an X-ray tube device, an X-ray detector arranged opposite to the Xa tube device with a subject in between, and converting a transmitted X-ray image into visible light. A television camera that captures this output optical image and converts it into an electrical signal, a television camera controller that controls the television camera, inputs the electrical signal from the television camera, and outputs it as a video signal; A memory device that converts a video signal into a digital quantity and records projection data, reads out the same, converts it into an analog signal, and reproduces the video signal, and a television monitor that displays the video signal from the memory device, Above X
In the X-ray television tomography apparatus that captures a plurality of images while changing the relative position of the ray tube device and the X-ray detector, and calculates and displays a tomographic image of a tomographic plane within the subject, the memory A tomographic image reproduction controller was connected to the apparatus to control the projection data recorded in the memory device at each imaging position to be sequentially and continuously read out and reproduced at a required time interval in units of fields or frames. This is done using an X-ray television tomography device.

[For production]

The X-ray television tomography apparatus configured in this manner emits X-rays to the subject while changing the relative positions of the X-ray tube device and the X-ray detector to capture multiple images. A tomographic image of a tomographic plane within the specimen is calculated and displayed, and the projection data is recorded in a memory device. Thereafter, the memory device is switched to playback mode, and each projection data at each imaging position is sequentially and continuously read out at a required time interval for each field or frame under the control of a tomographic image playback controller connected to the memory device. , the tomographic images at each imaging position are sequentially reproduced and displayed continuously. As a result, tomographic images are sequentially displayed while the X-ray tube device moves from the start position to the stop position, and the image below the overlapped portion with the bone is observed while looking at it from an oblique direction. It is something.

〔Example〕

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

FIG. 1 is a block diagram showing an embodiment of an X-ray television tomography apparatus according to the present invention. This X-ray television tomography apparatus emits X-rays to a subject to photograph and display a tomographic image of a tomographic plane inside the subject, and includes an X-ray tube device 1, an X-ray detector 3, It has a television camera 4, a television camera controller 5, a memory device 6, and a television monitor 7.

The X-ray tube device 1 emits X-rays to the subject 2, and is provided so as to move, for example, in the direction indicated by the arrow on a scanning trajectory (not shown). The X-ray detector 3 converts the transmitted X-ray image of the subject 2 into visible light, and is composed of, for example, an image intensifier, with the subject 2 in between. -, and is provided so as to move along a scanning trajectory (not shown) in the direction of arrow B, for example. The television camera 4 is connected to the X-ray detector 3
The output optical image is captured and converted into an electrical signal, and it is attached via a light distributor 9.

The television camera controller 1 to the roller 5 control the television camera 4 mentioned in "1" and also input electric signals from the television camera 4 and output them as video signals. The memory device 6 converts the video signal output from the television camera controller 5 into a digital quantity, records projection data, reads out the same, converts it into an analog signal, and reproduces the video signal. For example, the memory device 6 is used in a video tape recorder. (VTR) or video disc recorder (VDR)
Alternatively, it is composed of an IC memory or the like, and is configured to record and reproduce each projection data frame by frame at each photographing position. The television monitor 7 displays a tomographic image by inputting the video signal outputted from the memory device 6 mentioned above, and is made of a CRT. In addition, in Figure 1,
Reference numeral 8 is a table on which the subject 2 is placed.

Then, the two-dimensional X-ray transmission or absorption distribution of the subject 2 is determined by changing the relative positional relationship between the X-ray tube device 1 and the X-ray detector 3 as shown by arrows A and B. Images are captured, and from these multiple images, a linear operation is performed on a set of projection data passing through one point within the subject 2, and a tomographic image of an arbitrary tomographic plane within the subject 2 is calculated and displayed. It looks like this.

Here, in the present invention, a tomographic image reproduction controller 10 is connected to the memory device 6. This tomographic image reproduction controller 10 controls so that each projection data at each imaging position recorded in the memory device 6 is sequentially read out and reproduced in a field or frame unit at a required time interval. , as shown in FIG. 2, consists of an address selection circuit 11 and a repetitive reproduction control circuit 12. The address selection circuit 11 selects an address for recording and reproducing each projection data in the memory device 6, and during reproduction, it is possible to narrow or widen the range from which recorded projection data is retrieved. ing. The repetitive playback control circuit 12 also sets a time interval for playing back the projection data (for example, 3 times per second).
0 frames or 30 frames per 2 seconds), and controls to repeatedly execute this playback operation, such as repeatedly playing back only in the same direction as the recording of projection data, or playing back in the same direction. It is now possible to repeat playback while going back in the opposite direction.

Next, the operation of the X-ray television tomography apparatus configured as described above will be explained. First, in FIG. 1, the X-ray tube device 1 is moved in the direction of arrow A from the start position 1a to the stop position 1c, and along with this movement, the X-ray detector 3 is relatively moved in the direction of arrow B. Subject 2
Emit X-rays towards. Then, the transmitted X-ray image that has passed through the object 2 described in item 1 enters the X-ray detector 3 and is converted into visible light. Next, the output optical image from the X-ray detector 3 is reflected by the optical distributor 9 and enters the television camera 4, where it is photographed and converted into an electrical signal.

Next, the electrical signal from the television camera 4 is input to the television camera controller 5, and as shown in FIG. 2, it is output as a video signal S. Next, the video signal S1 from this television camera controller 5 is stored in a memory device 6.
Enter. At this time, a recording/reproduction switching signal S2 is input to the memory device 6 from an operation console or the like not shown, and the memory device 6 is in the recording mode. and,
The input video signal S1 is stored in the memory device 6 by A/
The data is converted into a digital quantity by D conversion, and recorded frame by frame as projection data at each imaging position. At this time, by selecting an address from the address selection circuit 11 of the tomographic image reproduction controller 10 shown in FIG. 2, the projection data is sequentially recorded at the designated address. At the same time, the projection data is read out from the address in the memory device M6, converted into an analog signal, and output as a video signal S3. This video signal S3 is input to the television monitor 7 and displayed as a tomographic image. In this way, the X-ray tube device 1 is moved to the starting position 1 in FIG.
After photographing the subject 2 while moving once or multiple times in the direction of arrow A from a to a stop position 1c, the X-ray radiation is shut off and the photographing is completed.

Thereafter, in order to reproduce the photographed tomographic image of the subject 2, as shown in FIG. 2, a recording/reproduction switching signal S2 is input from an operation console or the like not shown, and the memory device 6 is switched to the reproduction mode. Then, the address selection circuit 11 of the tomographic image reproduction controller 10 sequentially specifies the addresses of each projection data recorded in the memory device 6 in the same direction as when recording, and
The repeat reproduction control circuit 12 sets the time interval for reproducing each of the above projection data to, for example, 2 seconds and 30 frames. As a result, each projection data is repeatedly read out from the memory device 6 in frame units at a rate of, for example, 15 frames/second.

The video signal S3 is reproduced and the tomographic image is displayed on the television monitor 7. At this time, the displayed tomographic image is obtained by reading out each projection data at each imaging position in frame units as is, so the tomographic image is a tomographic image while the X-ray tube device 1 moves from the start position 1a to the stop position 1c. are displayed one after another. Therefore, as shown with diagonal lines in FIG. 4, even for affected areas that overlap with bone parts, etc., images are obtained by sequentially changing the shooting angle of oblique incidence from the oblique direction at the start position 1a to the reverse oblique direction at the stop position 1c. , the image of the affected area can be observed by looking diagonally below the overlapping area. Here, each projection data on the loaded plane can be read out sequentially for each frame as is, and each projection data on any tomographic plane other than the loaded plane can be read out so that the focus is on that tomographic plane. Data that has been shifted by an appropriate amount depending on the distance from the above-mentioned cross section may be sequentially read out for each frame.

In addition, since the images of which the photographing angles of oblique incidence are successively changed are displayed sequentially as described above, the tomographic image displayed on the TV monitor 7 is perceived as a three-dimensional image due to the afterimage effect of the observing eye. can do. Therefore, subject 2
The target inspection area can be observed in depth, even to the back of obstacles. At this time, when reproducing the tomographic image, by setting the range of the projection data retrieved from the memory device 6 to an appropriately narrower range than that during recording by the address selection circuit 11, the exposure angle of the X-ray radiation by the X-ray tube device 1 is adjusted. This can be done in the same way as when the image is made smaller, and the depth at which a three-dimensional image can be observed can be increased.

In the above description, each projection data is read out and reproduced from the memory device 6 under the control of the tomographic image reproduction controller 10 in units of frames, but the present invention is not limited to this, and the reproduction is performed in units of fields. Good too.

【Effect of the invention〕

Since the present invention is configured as described above, each projection data at each photographing position recorded in the memory device 6 can be successively read out and reproduced at required time intervals in units of fields or frames. Therefore, on the TV monitor 7, tomographic images are sequentially displayed while the X-ray tube device 1 moves from the start position 1a to the start position 1c. The image of the affected area can be observed by looking diagonally below the overlapping area. From this,
In image diagnosis of the subject 2, etc., the image of the targeted affected area can be observed better than before, and good diagnostic information can be obtained. In addition, since the tomographic images whose photographing angles are sequentially changed as described above are displayed one after another, the tomographic images displayed on the television monitor 7 can be perceived as a three-dimensional image due to the afterimage effect of the eye observing the tomographic images. Can be done. Therefore, the target inspection site of the subject 2 can be observed with depth, even down to the back side of the obstacle. For these reasons, the clinical value of the X-ray television tomography apparatus can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an X-ray television tomography apparatus according to the present invention, FIG. 2 is a block diagram showing details of a tomographic image reproduction controller, and FIG. 3 is a block diagram showing a conventional X-ray television tomography apparatus. The block diagram shown in FIG. 4 is an explanatory diagram showing a tomographic image in a state where the affected area is difficult to see because it overlaps with bones etc. 2. ]... X-ray tube device, 2... Subject, 3... X-ray detector, 4... Television camera, 5... Television camera controller, 6... Memory device, 7.
...TV monitor, 8.Table, 9.Optical distributor, 10.Tomographic image reproduction controller, 11.Address selection circuit, 12.Repeat reproduction control circuit.

Claims (1)

[Claims] An X-ray tube device, an X-ray detector placed opposite to the X-ray tube device with the subject in between and converting the transmitted X-ray image into visible light, and capturing this output optical image and converting it into an electrical signal. a television camera that controls the television camera; a television camera controller that controls the television camera and inputs electrical signals from the television camera and outputs them as video signals; and a television camera controller that converts the video signals from the television camera controller into digital quantities and outputs projection data. It has a memory device for recording and reading out and converting the analog signal to reproduce a video signal, and a television monitor for displaying the video signal from the memory device, and a TV monitor for displaying the video signal from the memory device, In the X-ray television tomography apparatus that captures multiple images while changing the position of the subject, and calculates and displays tomographic images of tomographic planes within the subject, the memory device stores information about each of the images recorded in the memory device. 1. An X-ray television tomography apparatus, characterized in that a tomographic image reproduction controller is connected to control the projection data at each position to be sequentially and continuously read out and reproduced at required time intervals in units of fields or frames.