JPH03106343A - X-ray picture diagnostic device - Google Patents

Abstract

PURPOSE:To instantaneously confirm a picture-processed energy subtraction image further to eliminate space for film storage by a picture control through a computer by providing a dual energy generating mechanism in front of an X-ray tube. CONSTITUTION:A plate-shaped dual energy filter 2, in which a hole is partly drilled, is arranged in an irradiation port of an X-ray tube 1. By rotating this filter 2 synchronously with a frame rate of a TV camera 4 by a host computer CPU 13, an X-ray of different energy can be instantaneously generated without changing a tube current and tube voltage of the X-ray tube. When energy subtraction is performed, X-ray images by two kinds of energy, obtained in each one frame of the TV camera 4, are continuously collected, and by subtracting a video signal of the previously frame from a video signal of a certain one frame by an image processor 8, the energy subtraction is executed with its image stored in a frame memory 7 or in a display memory 10 and displayed by being input to a CRT display device 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an X-ray image diagnostic apparatus, and particularly to an X-ray image diagnostic apparatus that performs energy subtraction processing.

[Prior art] Energy subtraction method (
energy difference method). This is a method in which a specific region is photographed using high-energy and low-energy X-rays, and an appropriate weight is applied to the two images to perform subtraction. Among the structural substances of the human body, bones and muscles have different absorption characteristics depending on the X-ray energy, so if images are taken with two different energies, the contrast of the patient will change. Therefore, by changing the load and performing subtraction, it is possible to erase the bones and create an image of only the muscles. Also, if you adjust the energy of the X-rays so that the average energy comes before and after the K-absorption line of iodine and perform energy difference,
The location of the contrast agent appears in strong contrast.

Conventionally, to perform this energy subtraction, in the film method and combined radiography, a filter is inserted between two films or two IPs (imaging plates). Images were collected by obtaining images using X-rays of different energies (1) (2). In order to perform subtraction, in the case of film, the image is digitized using a film digitizer, and a digital processing device is used to perform image calculations to perform subtraction.

[Problems to be Solved by the Invention] In the conventional energy subtraction method, it took time to confirm the collected images, and additionally, it required image management space necessary for film storage, etc.

The present invention was devised to eliminate the above-mentioned drawbacks of the prior art, and allows immediate confirmation of image-processed energy subtraction images, and furthermore, saves space for film storage through image management by computer. , an object of the present invention is to provide an X-ray image diagnostic apparatus.

[Means for Solving the Problems] In order to achieve the above object, the X-ray image diagnostic apparatus of the present invention has a dual energy generation mechanism at the X-ray irradiation port of the X-ray tube.

[Operation] The X-ray image diagnostic apparatus configured as described above uses a dual energy generation mechanism that is synchronized with the image acquisition timing to generate X-rays with different energy at each image acquisition timing, and the resulting X-ray Images are recorded and stored in memory and other recording media, and energy subtraction image operations are performed by an image processing processor.

[Example] An example will be described with reference to FIG.
At the irradiation port, a plate-shaped dual energy filter 2 with a hole as shown in FIG. 2 is arranged. By rotating this filter 2 by the host computer CPU 13 in synchronization with the frame rate of the TV camera 4, X-rays of different energies can be generated instantaneously without changing the tube current and tube voltage of the X-ray tube. I can do it.

On the other hand, the X-rays that have passed through the subject are converted into a visible image by an X-ray image intensifier 3, and converted into a video signal by a television camera 4. This video signal is converted into a digital signal by an A/D conversion circuit 5, subjected to processing such as noise removal by an image processor 6, and then stored in a display memory 10. The contents of this display memory 10 are read out and D/A
The conversion circuit 11 converts the signal into an analog signal, and the CRT display device 12 displays the transparent image. When collecting images, press
Images are obtained by increasing the tube voltage and current of the wire tube compared to the fluoroscopy,
This image is input into the frame memory 7 after A/D conversion. When energy subtraction is performed, X-ray images of two types of energy obtained for each frame of the television camera 4 are continuously collected, and the image processor 8 converts the video signal of one frame into the video signal of the previous frame. By being subtracted,
Energy subtraction is performed and an energy subtraction image is stored in frame memory 7 or display memory 10. The output of this display memory IO is D/
It is converted into an analog signal by the A conversion circuit 11 and sent to the CRT.
An energy subtraction image is displayed by inputting it to the display device 12. At this time, when collecting at the frame rate of the TV camera 4, it is possible to collect an image of the work piece in 1/30 seconds, and if an image is obtained every 3 frames to remove noise etc., considering the calculation time. Also, one energy subtraction image can be obtained in less than one second.

Further, the digital images are recorded on a large-capacity image disk 9 and managed by the host computer 3 in order to perform more advanced processing later or to save the data. This makes it possible to examine differences with past energy subtraction images.

In the above example, a plate-shaped filter with holes was used to generate X-rays of different energies, but the energy can be adjusted by varying the material or thickness used for the filter in some parts of the filter. You can also do that.

Furthermore, by changing the rotation period of the filter, it is possible to print dual energy images onto film using conventional film methods.

[Effects of the Invention] As explained above, the present invention has a dual energy generation mechanism in front of the X-ray tube, so images with two different types of energy can be collected continuously, and energy subtraction images can be obtained. You can check it immediately on the monitor. Furthermore, if the collection rate is short, position correction is not necessary when performing energy subtraction processing.

Furthermore, since the recorded images are managed by the host computer, data loss can be prevented and storage space can be reduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an X-ray image diagnosis apparatus embodying the present invention, and FIG. 2 is a diagram showing an example of a dual energy filter used in the X-ray image diagnosis apparatus of FIG.

Claims (1)

[Claims] (1) It is characterized by having an X-ray tube, a dual energy generation mechanism provided at the X-ray irradiation port of the X-ray tube, and a processing device that performs energy subtraction processing using the image obtained from the subject. X-ray imaging diagnostic equipment.