JPS58220587A - X-ray picture image processor - Google Patents

Abstract

PURPOSE:To move a photographing position of a formed image in relation to the photographing position of a contrast image with respect to the photographing position of a mask image, by putting whole photographing area on coordinates for each photographing position when photographing before imaging, and by recording an image informtion after imaging in correspondence with to the coordinates. CONSTITUTION:When photographing before injecting a imaging agent, if a mask image taking- in signal 8 is inputted, horizontal and vertical direction moving devices 4 and 5 are driven with a specified cycle to move photographing devices 1 and 3 over whole movement area. The coordinates of each position is outputted from individual horizontal and vertical coordinates detection circuits 6 and 7. On the other hand, one image plane of a photographing at each position is put on coordinates by individual horizontal and vertical coordinates counter circuits 14 and 15. Individual horizontal and vertical thrshold setting devices 12 and 13, the counters 14 and 15 and the detection circuits 6 and 7 determine relative coordinates, and a recording address designating circuit 18 desigates an address. An image information recorder 20 records the information of an A/D conversion circuit 19 in its address. After injecting the contrast medium, an x-ray tube 1 is set to a diagnostic part, and the outputs of individual horizontal and vertical coordintes decision circuits 16 and 17 are inputted in a circuit 21 which designates the address of an image information which is used as a mask image.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention provides an X#! The present invention relates to an X-ray image processing device that digitally subtracts an X-ray image before contrast and an X-ray image after contrast to extract only a contrast region when outputting a video of a picture monk by means of a television.

[Technical background of the invention]

Generally, X-ray diagnostic equipment uses X-ray film directly on the X-ray film.
There is a method of forming an image, and a method of forming an indirect KX-ray image using an X-ray television device that combines an image intensifier as an X-ray-light converter, a television, a camera, and a television monitor.

Furthermore, there are two types of X-ray imaging methods: a method in which the area to be imaged is directly imaged without any manipulation, and a method in which the area to be imaged is emphasized using a contrast agent.

Recently, in the case of contrast imaging, particularly angiography, a so-called digital radiography method has been used in which an X-ray television apparatus is used and the captured X-ray image information is subjected to arithmetic processing to extract only the contrasted region.

In this method, the video signal of the X-ray image (mask image) obtained by photographing the state before the contrast agent is injected is digitally converted in time series [and the information for one screen is recorded in the recording device]. . Next, the video signal for one screen of an X-ray image (contrast image) obtained by photographing the state in which the contrast medium is injected is digitally converted in time series. Then, in the subtraction device, the contrast image information is subtracted in chronological order from the mask image information recorded in the recording device (subtraction>f). Then, if the imaging conditions are the same, the region that is not affected by the contrast agent is Since the mask image signal and the contrast image signal directed toward the target are equal, subtraction becomes zero, and the mask image signal and the contrast image signal at the site where the contrast agent is injected differ due to X-ray absorption by the contrast agent trap, and this difference occurs. When the digital signals of the differences are converted into analog signals in time series and recombined on a TV monitor, only the contrasted region is output as a video.Therefore, this method extracts only the contrasted image of the region to be diagnosed. This is a useful method for diagnosis.

[Problems with background technology]

However, in order to carry out this method, the mask image and the contrast image must match, so conventionally the imaging position has been fixed at one location. J-5 had the disadvantage that it required an image intensifier with a larger aperture, and that the resolution decreased due to the wide shooting range. Furthermore, even if the imaging position can be set at two or more locations, the imaging position of the contrast image must be the same as the imaging position of the mask image. Even if you want to move the imaging position of the contrast image in order to move it to the center of the TV screen when the mask image is in the center of the TV screen, it is impossible because subtraction cannot be performed if the contrast image is shifted from the imaging position of the mask image. was there.

[Purpose of the invention]

This invention has been made based on the above circumstances, and an object of the present invention is to provide an X-ray image processing apparatus in which the imaging position is movable and the imaging position of a contrast image can be moved relative to the imaging position of a mask image. This is the purpose.

[Summary of the invention]

In order to achieve the above object, the present invention digitally subtracts the X-ray image before contrast and the X-ray image after contrast when outputting the Xi image photographed by the photographing means by the television means. In the X-ray image processing apparatus for extracting only the image, the entire moving area of the imaging means is divided into coordinates by subdividing one screen area of the television means for each imaging position during imaging before contrast imaging. , X before contrast
The apparatus is characterized by comprising means for recording line image information in correspondence with the coordinates.

[Embodiments of the invention]

The present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 1 is a block diagram for recording a mask image.

In the figure, 1 is an X-ray tube that irradiates X@, 21 specimens, Roha X
4 is an image intensifier (I/I) that converts the X-rays emitted from the ray tube 1 and transmitted through the subject 2 into light;
A lateral moving device 5 moves the X-ray tube 1 and the image intensifier 6 laterally while keeping their relative positions fixed; A vertical movement device 6 for vertically moving the X1IJ tube 1 and the image intensifier 6 is incorporated in the horizontal movement device 4, and a horizontal coordinate detection circuit detects the position coordinates of the X1IJ tube 1 and the image intensifier 6 at each shooting position in the horizontal direction. 7 is incorporated in the vertical movement device 5, and 8 is a vertical coordinate detection circuit that detects the position coordinates of the X-ray tube 1 and the image intensifier 3 at the simultaneous shooting positions in the vertical direction; 8 is the horizontal movement device 4 or This is a mask image capture signal that drives the vertical movement device 5 at a predetermined period by the pitch between the photographing positions. 9 is an X# television and camera device that scans the output optical image of the image intensifier 3 and converts it into a video signal, 10 is a horizontal synchronization signal extraction circuit built into the X@TV camera device 9, and 11 is an X-ray television. A vertical synchronization signal extraction circuit 12 built into the camera device 9 divides one screen of the X-ray television camera device 9 at each imaging position of the X-ray tube 1 and image intensifier 6 into multiple areas along the horizontal direction. A horizontal division threshold setting device 16 divides one screen of the X-ray television camera device 9 at each imaging position of the X-ray tube 1 and the image intensifier 3 into a plurality of screens along the vertical direction. Vertical division threshold setter for dividing into regions and setting division thresholds, 1
4 is a horizontal division coordinate counter circuit which compares the horizontal synchronization signal of the horizontal synchronization signal extraction circuit 10 with the setting value of the horizontal division threshold value setter 12 and determines in which region of the division areas the horizontal synchronization signal is located; 15 is a vertical division coordinate counter circuit that compares the vertical synchronization signal of the vertical synchronization signal extraction circuit 11 with the set value of the vertical division threshold value setter 16 to determine which region of the division areas the vertical synchronization signal is active; 17 is a horizontal coordinate determination circuit that determines the relative coordinate in the horizontal direction from the output of the horizontal coordinate detection circuit 6 and the output of the horizontal division coordinate counter circuit 14, and 17 is the output of the vertical coordinate detection circuit 7 and the vertical division coordinate color/
A vertical coordinate determination circuit 18 determines the relative coordinates in the vertical direction from the output of the horizontal coordinate determination circuit 16 and the output of the vertical coordinate determination circuit 17. 19 is a recording address designation circuit; 19 is an X-ray television camera; 20 is a conversion circuit that converts the output video signal of the device 9 into a digital signal; 20 is a conversion circuit that converts the image information output from the conversion circuit 19 to a recording address designation circuit 18; This is an image information recording device that records at a designated address.

FIG. 2 is a block diagram for performing subtraction in which a contrast image is subtracted from a mask image. Partial pressures similar to those in FIG. 1 are shown with the same numbers, and some of them are omitted. In the figure, reference numeral 21 designates the address where image information to be used for subtraction as a mask image is recorded, in response to outputs from the horizontal coordinate determining circuit 16 and the vertical coordinate determining circuit 17 when performing subtraction. An address designation circuit; 22 is a recording data reading circuit that receives the output of the recording address designation circuit 21 and reads out the image information of the designated mask image from the image information recording device 20; 26 is a mask output from the recording data reading circuit 22; From the image information, l
24 is a D/A converter that converts the output signal of the subtraction circuit 26 into an analog signal; 25 is a D
This is a television monitor that outputs the output signal of the /A converter 24 as a video.

X configured as above? The fs image processing device operates as follows. First, when photographing the state before injecting the contrast medium, the X-ray tube 1 and image intensifier 6
Assume that the initial state is at the position AK in FIG. When the mask image capture signal 8 is input, the lateral movement device 4 is driven at a predetermined period to move the X-ray tube 1 and image intensifier 3 from AK to BK, CK, and DK in FIG.
Then, the vertical movement device 5 drives the D
The X-ray tube 1 and the image intensifier 6 are moved from K to DL, and the lateral movement device 4 is driven again to move the DL to CL, BL, and AL in the 11th order.
This means that the entire moving area of the area will be moved. And A.K.
, BK, . . . AN are outputted from the abscissa detection circuit 6 and the ordinate detection circuit 7. On the other hand, the X-ray tube 1 and the image intensifier 6 perform X-ray photography at each position trap of AKBK, . . . The vertically divided coordinate counter circuit 15 divides the image horizontally and vertically and assigns coordinates. That is, if the X-ray tube 1 and the image inch/shift arrow are located at the position AK in FIG. The division setting value is set, and the vertical division threshold setting device 13 has a fourth
In the figure, division setting values of 1 and X2 and division setting values of 2 and 6 are set. Then, the horizontal division coordinate counter circuit 14 determines that the horizontal synchronization signal is in the area of A1 when the horizontal synchronization signal is smaller than the division setting value of A1 and A2, and also determines that the horizontal synchronization signal is in the area of A1. If it is larger than the division setting value of A2 and A6, it is determined that the horizontal synchronizing signal is in the A2 area, and if it is larger than any of the division setting values of A2 and A3, the horizontal synchronizing signal is in the A6 area. It is determined that it is in the area of . The vertical division coordinate counter circuit 15 determines that the vertical synchronizing signal is in the region of 1 when the vertical synchronizing signal is smaller than the division setting value of 1 and 2, and also divides the vertical synchronizing signal into 1 and 2. If it is larger than the setting value and smaller than the division setting value of 2 and 3, it is determined that the vertical synchronization signal is in the region 2, and if it is larger than the division setting value of 2 and 6. determines that the vertical synchronization signal is in the range 3. Then, relative coordinates in the horizontal direction are determined in the horizontal coordinate determining circuit 16 from the determined coordinates of the horizontally divided coordinate counter circuit 140 and the output coordinates of the horizontal coordinate detecting circuit 6, while the horizontally relative coordinates are determined by the determined coordinates of the vertically divided coordinate counter circuit 150 and the output coordinates of the horizontal coordinate detecting circuit 6. From the output coordinates of 7, the vertical coordinate determination circuit 17 determines the relative coordinates in the vertical direction, and from both relative coordinates, the recording address designation circuit 18 designates the recording address. The image information of the mask image output from the circuit 19 will be recorded at the designated address.

Next, when photographing the state in which the contrast medium has been injected, the X-ray tube 1 and image intensifier 3 are set to the desired position of the region to be diagnosed. Then, at this position, the outputs of the horizontal coordinate determination circuit 16 and the vertical coordinate determination circuit 17 are input to the recording readout address designation circuit 21, and the recording readout address designation circuit 21 records the image information to be used for subtraction as a mask image. The next address is set to 5 and judged. Assuming that the abscissa of the input detection coordinate is A3 in Figure 4, and the ordinate is the city, the TV-screen valve is divided into 6 parts in the water direction and 6 parts in the perpendicular direction. Therefore, the screen corresponding to the detected coordinate A3, 3 is shown by the following matrix.

Therefore, the recording readout address designating circuit 21 designates an address corresponding to this matrix, and in response to this, the recording data reading circuit 22 reads out the mask image information at the designated address from the image information recording device 20, and subtracts the mask image information from the subtraction 11g circuit 23. This will require manual labor. On the other hand, the XIf8 tube 1 and the image intensifier 6 photograph a contrast image at the set position, and the photographed IftI image is sent to the X-ray television camera device 9 and the A/D K extraction circuit 19 as contrast image information to a subtraction circuit. 26. The subtraction circuit 26 subtracts the contrast image information from the mask image information in chronological order to extract only the contrast region, and the image of only the contrast region is output as a video from the television monitor 25 through the D/A conversion circuit 24. Become.

In addition, when the X-ray tube 1 and image intensifier 6 are moved and repositioned to move the part to be diagnosed, the mask image information of the address corresponding to that position is read out from the image information recording device 20. Therefore, the television monitor 25 outputs an image of only the contrast region at that position.

In the above embodiment, the screen is divided into 6 vertically and horizontally when recording a mask image, but the screen is not limited to this. It becomes possible to move more smoothly.

〔Effect of the invention〕

As is clear from the above explanation, 1. According to the present invention, the imaging position can be moved, and therefore, even when performing a wide-area diagnosis, a large-diameter image intensifier is not necessary and a small-diameter image intensifier is sufficient, resulting in a high resolution does not decrease. In addition, the imaging position of the contrast image can be moved relative to the imaging position of the mask image. Therefore, for example, if the extracted contrast image is at the edge of the TV screen, it is possible to move it to near the center of the TV screen. It has excellent effects such as making diagnosis easier.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a block diagram for recording a mask image, and Fig. 2 is a block diagram for performing subtraction to subtract a contrast image from the mask image. FIG. 4 is an explanatory diagram showing the moving area of the device, and FIG. 4 is an explanatory diagram showing coordinate division and its detection. DESCRIPTION OF SYMBOLS 1... X-ray tube, 2... Subject, 6... Image intensifier, 4... Lateral movement device,
5. U. Vertical direction movement device, 6. Abscissa detection circuit, 7. Vertical coordinate detection circuit, 8. Mask image capture signal, 9. X-ray television camera equipment d, 1o.・・・
Horizontal synchronization signal extraction circuit, 11... Vertical synchronization signal extraction circuit, 12... Horizontal division threshold setter, 16...
・Vertical division threshold setting device, 14...Horizontal division coordinate counter circuit, 15...Vertical division coordinate counter circuit,
16... Horizontal coordinate determination circuit, 17... Vertical coordinate determination circuit, 18... Recording address designation circuit, 1
9... Le conversion circuit, 20... Image information recording device,
21...Record readout address designation circuit, 22...
Recorded data reading circuit, 26... subtraction circuit, 24.
...D/A conversion circuit, 25...TV monitor.

Claims (2)

[Claims] (1) For outputting the X-ray image taken by the photographing means by the television means, only the contrasted region is extracted by digitally subtracting the X-ray image before contrast and the X-ray image after contrast. #J In the image processing device, during busy imaging before contrast imaging, means for subdividing one screen area of the television means into coordinates by dividing the entire movement area of the imaging means into its imaging position; An X-ray image processing apparatus comprising: means for recording line image information in correspondence with the coordinates. (2) The X-ray image taken by the imaging means is transmitted to the television means [When outputting the image, the pre-contrast X-ray image and the post-contrast X-ray image are digitally subtracted to produce only the contrast area. In the X-ray image processing apparatus for extracting the means for recording line image information in correspondence with the coordinates; means for detecting positional coordinates of the imaging means arbitrarily set during imaging after contrast imaging; and means corresponding to the coordinates detected by the detection means; and means for reading out X-ray image information corresponding to one screen of the television means from the recording means.
1lj! Image processing device.