JPS5812645A - X-ray television photographing 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 The present invention relates to a high-resolution X-ray television imaging apparatus (hereinafter referred to as "X-ray TV apparatus") that allows setting of a region of interest of a subject.

Conventional X-ray TV devices can be roughly divided into the following two types.

(2) A method in which the subject is viewed through an X-ray TV device, a region of interest is set from the X-ray fluoroscopic image, and a predetermined area (for example, an affected area) of the subject is determined before being photographed on film.

(2) A method in which the subject is viewed through an X-ray TV device and the X-ray fluoroscopic image is directly stored in a storage device.

In the case of method (1) above, the X-ray TV device is sometimes used only for positioning the region of interest and sometimes for dynamic examination, but due to the need to minimize X-ray exposure, Since the X# irradiation dose is small, the image does not have sufficient image quality.

The latter had the problem of having a small dynamic range and not being able to obtain sufficient contrast resolution when shooting with film.

In the case of method (2) above, there are two ways to process the X-ray fluoroscopic image: analog processing and digital processing.When using analog processing, X-ray exposure can be minimized by recording one frame, but it is not possible to quantify it. When using digital processing, it is possible to record and quantitatively analyze one frame with minimal X-ray exposure, but digital processing of video signals requires high-speed image processing. Yes, when increasing the number of scanning lines to increase resolution, (a) high-speed analog
A digital conversion element and a large capacity storage device are required. Further, (b) there were problems such as poor S/N ratio in high bands and limited dynamic range.

The present invention was made to solve the above problem, and its characteristics are that X-rays transmitted through the subject are imaged with an image intensity and an ear, and the imaged image is captured and stored with a television camera. An X-ray television imaging apparatus for reproduction includes means for setting a region of interest of a subject, and means for scanning and displaying only the region of interest by changing the deflection position and deflection amplitude of the image pickup tube and monitor of the television camera. It's about being prepared.

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIGS. 1A, B, and 0 are diagrams for explaining the present invention in detail, where A is an overall X-ray fluoroscopic image of the subject displayed on a monitor, and B is an overall X-ray fluoroscopic image. A set image of the region of interest,
C is a high-resolution enlarged image of the region of interest.

(3) As shown in FIG. 1A, the X-ray television imaging apparatus of the present invention first projects an entire image of the subject on a monitor using a television camera, and then uses a region of interest setting device while viewing the image. , as shown in FIG. 1B, a region of interest of the subject is set. Next, by changing the deflection position and deflection amplitude of the image pickup tube of the television camera and the monitor, only the region of interest is scanned, and a high-resolution enlarged image of the region of interest is displayed on the monitor, as shown in FIG. 1C. Make it look like 11 times.

Furthermore, the entire image of the subject and the high-resolution enlarged image of the region of interest can be displayed either alone or simultaneously using a changeover switch. This allows the two to be observed in correspondence.

FIG. 2 is a diagram showing the configuration of an embodiment of the X-ray television imaging apparatus of the present invention.

In Figure 2, 1 is an X-ray tube, 2 objects to be examined, 3 is an image intensifier that converts the transmitted X-ray image of the object 2 into visible light, 4 is a television camera, and 5 is an analog-to-digital converter. , 6 is an image memory, 7 is a digital-to-analog converter, 8 is a monitor for (4) a cathode ray tube, etc., 9 is a region of interest setting device for a subject,
108 to 10D are digital-to-analog converters; 11 is a horizontal deflection circuit for the television camera 4 and monitor 8;
2 is a vertical deflection circuit for the television camera 4 and monitor 8; 13 is a synchronization signal generator for horizontal and vertical synchronization.

FIG. 3 is a diagram showing a specific circuit configuration of the region of interest setting device 9 of FIG. 2, and the same parts as in FIG. 2 are given the same symbols. In FIG. 3, 20 is a bright line signal generator;
21 is a region of interest setting switch.

region of interest switch 21A for setting bright line X1;
Region of interest switch for setting bright line X2, 21B.

It consists of a region of interest switch 21C for setting the bright line Y1, a region of interest switch 21C for setting the bright line Y2, and a region of interest switch 21D for setting the bright line Y2.

22 to 25 are counters, and 26 is a clock generator.

Next, the operation of this embodiment will be explained.

In FIG. 2, X-rays from an X-ray tube 1 pass through a subject 2 and enter an image intensifier 6, where they are converted into a visible image and displayed on the output surface of an image intensifier 3. displayed as an image. The X-ray fluoroscopic image projected on this output surface is captured by the television camera 4,
Output as an analog video signal. This analog video signal is converted into a digital signal by an analog-to-digital converter 5 and stored in an image memory 6.

The digital signal stored in the image memory 6 is converted into an analog video signal by a digital-to-analog converter 7, and an entire X-ray fluoroscopic image of the subject 2 is displayed on a monitor 8.

Next, while observing the entire X-ray fluoroscopic image, the region of interest setting switches 21A to 2 of the region of interest setting device 9 shown in FIG.
1)) to set the region of interest for the entire X-ray fluoroscopic image. That is, when the region of interest switch 21A for setting the bright line X1 is tilted to either the right or left direction, the counter 22 is set to black.

Counting is started by a clock pulse from Kuhars generator 26. At this time, the counter 22 counts up when the X1 setting region of interest switch 21A is pushed to the right, and counts down when pushed to the left. The output signal counted by the counter 22 determines the start address of the image memory 6, and is used by the bright line signal generator 20.
The output signal of the counter 22 rewrites the image memory 6 corresponding to the vertical line of the X-ray fluoroscopic image to constant data, and the first
As shown in FIG. B, the bright line X1 is displayed on the monitor 8.

In the same way, switch the region of interest switch for setting bright line X2, switch 1B, switch the region of interest switch for setting bright line Y bright line By turning the image memory 6 upside down, the contents of the image memory 6 are rewritten to the corresponding constant data, and as shown in FIG.
As shown in the bright line X2. Bright line Y1. Monitor bright line Y2 8
Projected on top.

Next, the bright line signal generator 20 of the region of interest setting device 9 operates from the specified address to the horizontal and vertical deflection circuits 11.1.
2, and the calculated values are converted into analog signals by digital-to-analog converters 10A to 10D and input to horizontal and vertical deflection circuits 11 and 12, respectively. As a result, the television camera 4 detects the subject 2.
The same number of scan lines (e.g., 512
In synchronization with this, a high-resolution X-ray fluoroscopic image of the region of interest enlarged on the entire surface of the monitor 8 is obtained. When it is desired to record this X-ray fluoroscopic image on film, it is photographed on film.

As described above, according to the present invention, a high-resolution enlarged image with good contrast resolution of a region of interest of a subject can be obtained. Furthermore, high-speed image processing is possible without increasing the image memory capacity and without using a high-speed image processing element.

[Brief explanation of the drawing]

FIG. 1 is a detailed explanation diagram of the present invention, FIG. 2 is a diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram showing a specific example of the region of interest setting device of FIG. FIG. 3 is a diagram showing a circuit configuration. 1 - X-ray tube 2 Subject 3 - Image intensifier 4, television camera 5 Analog-to-digital converter '6 - Image memory 7 Digital-to-analog converter 8 Monitor 9 - Region of interest setting device 10A to 10D Digital-to-analog Converter 11 Horizontal deflection circuit 12 Vertical deflection circuit 16 Synchronizing signal generator agent Patent attorney Aki 1) Figure 1 (A) (B) (C)
#2 Figure

Claims (1)

[Claims] In an X-ray television imaging apparatus that images X-rays transmitted through a subject with an image intensifier, and captures and stores and reproduces the captured image with a television camera, means for setting a region of interest of the subject; An X-ray television set comprising means for scanning only the region of interest by changing the deflection position and deflection amplitude of an image pickup tube of the television camera. imaging device.