JPS58163343A - X-ray diagnostic 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 [Technical field to which the invention pertains] The present invention belongs to the technical field of X@ imaging devices, and particularly relates to a diagnostic device using digital radiography.

[Technical background of the invention and its problems]

In recent years, with regard to xlI diagnosis and IfiPK angiography, a technology called ``Digital Radiog 2fi'' or ``Digital Fluoroscopy'' has been developed by applying Time Napto2 Vm technique and digital processing technology. It is applied.

The outline of the digital radiography described above will be explained next.◎ As shown in Fig. 1, first, a vascular contrast agent is injected into the brachial vein of a patient O, for example, and after a time T (for example, several seconds) has passed. Areas of the patient to be examined where the angiographic medium flows during the first X-ray exposure, such as the AS1 head, kidneys, abdominal vascular system, lower limbs, aorta, pulmonary artery, peripheral vasculature, etc., are imaged with the TXL II TV camera. Then, the X1M TV camera 2 will be powered by pIH! I TV video signal [-A/
The digital X-ray TV image signal is converted into D and stored as a mask image in the first digital memory.Next, after the first X@ exposure, time TI, for example, 1 second has passed, and at 9 o'clock, the second After the second X-ray exposure, for example 1
Intermittent KX-ray exposure at a rate of 1 per second.
A/D converted digital XIi! TV video signal 1 - Stored in the 20th digital memory ◎ Then, when the X-ray TV video signal in the second digital memory is subtracted with the X-ray TV video signal in the first digital memory, the blood vessels A subtraction image signal is synthesized, which is a subtraction image of a blood vessel image into which a contrast medium is flowing, and this naptraction image signal tD
/A conversion is performed to obtain an analog subtraction video signal, and a subtraction image 5 as shown in Fig. 1 is obtained.
The subtraction image is displayed on a CIA' monitor, or the subtraction image is made into a film image using a multi-format camera.

Digital 2Geography can be applied not only to conventional angiography injection methods using arterial catheters, but also to intravenous injection methods that do not use arterial catheters, making it possible to make safe, quick, and accurate diagnoses. It has attracted a lot of attention in recent years because of its advantages.

However, the image pickup tube in the X-ray television camera 2 used in the X-ray diagnostic apparatus applying the digital 2 geography, for example, the vidicon type image pickup tube, generally has residual phenomena. +, therefore %XIm! Xa TV video signal from a TV camera (hereinafter sometimes referred to as video signal)
output start-up] is poor.

When #i man is in the X1ij@shot sequence shown in Figure 1,
Nine example i! As shown in Figure 2, X! The iI pulse enters the image intensifier (hereinafter referred to as 1.1), and the 1@1 output fluorescent image obtained by photoelectric conversion enters the image pickup tube as a light pulse. (g) in Figure 2] The video signal gradually rises (A in Figure 2) Since the image pickup tube in the xm TV camera 2 uses interlace TV 2 canning, the video signal 4th field and 5th field video signal 'fc 1 piece of Xa
It will be stored in the digital frame memory as S. Then, one X-ray (as the exposure of Luz),
In addition to the exposure time required for the line image, the exposure time for rounding the rising edge of the image pickup tube's video signal output is required, and the patient is also given unnecessary X@ exposure. Become. This is a problem regarding the safety of subjects against xliI.

[Purpose of the invention]

This invention was made in view of the above circumstances.
The object of the present invention is to provide an X6 diagnostic device that eliminates wasted tS radiation time, makes efficient use of X-rays, and increases the safety of the subject against X@.

[Summary of the invention]

To achieve the above object, the present invention provides an X-ray tube that irradiates X-rays, an X-ray high voltage generator that supplies high voltage to the X-ray tube, and converts Xa transmitted N11 into an optical image. an image intensifier and an optical system device that guides the optical image to the photoconductive surface of the image pickup tube in the XII television camera (an optical system device and an X-ray television camera that converts the optical image guided to the photoconductive surface into a video signal); , an X-ray diagnostic apparatus comprising at least a Nattu 2 spider display device for converting video signals into digital signals, and a system controller 2 for controlling each of the devices, wherein a bias fit is disposed within the optical system scissors holder. This is because the X-ray exposure is performed by the Xg tube after compensating for the residual 11411 effect of the rise of the image pickup tube by irradiation with light of bias 2.

[Embodiments of the invention]

An embodiment of the present invention is shown in Figure 5. In the same figure, 1 indicates the XII
The image intensifier (1@7) is an image intensifier (1@7) that receives the Aon specimen transmitted X@image and converts it into an X-ray at optical image. 2 and 3 are the image intensifiers (1@7) that convert the Aon sample transmitted X@ image into an optical image as a subject. This is a companion optical lens system, a so-called tandem lens system, which converts the 0 light that is imaged on the gII plane into a parallel beam from the nine optical images, and then focuses it on the photoconductive surface of an image pickup tube, such as a vidicon camera tube. . Also, 3' indicates an automatic optical iris (auto iris) placed in front of the lens 3 on the image pickup tube side to adjust the amount of parallel light, and 4 indicates the auto iris in front of the lens 3. A bias light placed near the focal point to create bias light.
, 5 is a light-shielding plate to prevent the light from the bias light 4 from entering l-11, and 6 is a light shielding plate to make the light from the bias light 4 uniform. For example, it is a diffusing surface such as ground glass, and 7 is an imaging tube 19 arranged so that its photoconductive surface is located at the focal point behind the optical lens 3. ], 8 indicates the tandem lens system!
First of all, it is a housing for an optical system device made up of various parts.

9 is the object to be examined, pl 10 is the image pickup tube 7
This is a TV camera control unit that controls the X@TV camera and seven sub-controllers. Reference numeral 11 indicates a digital device (t), an A/D converter, a digital frame memory, and an algorithm for converting naptracidine.
The video signal tube A/D converter, which is equipped with a D/A converter, etc., outputs from the image pickup tube 7 in the X-ray television camera, converts it into a digital signal, stores the digital video signal in a digital frame memory, and processes the algorithm. It is constructed to obtain a naptraxine image from a mask and a digital video signal f from a mask and a digital video signal f which is converted into an analog video signal by a D/A converter and output this.

Reference numeral 12 indicates that the video signal output from the digital processor 11 is switched off so that it is output to a predetermined device.
1S is an external memory, such as a video disk recorder or a video tape recorder), and 14 is a television monitor.

15 is the system controller that controls the entire system of the xJI diagnostic device;
016, which controls the timing of irradiation and X@ exposure, is the X-ray controller that controls xII exposure.
Reference numeral 17 is an xm high voltage generator for generating a high voltage to be applied to the X-ray tube), and reference numeral 18 is an X-ray tube that irradiates X-rays.

Reference numeral 19 indicates a contrast medium injection device for injecting a vascular contrast medium into the blood vessel of the subject 9.

Next, the operation of the above-mentioned component device will be explained with reference to FIG.

First, after a contrast agent is injected into the subject 9 using the contrast agent injection device 19, after a time T (for example, several seconds) has elapsed,
The bias slide 4 is turned on under the control of the system controller 15, and the surface is irradiated with the light guide of the image pickup tube 7 from the bias light 4 for one hour t1 as shown in FIG. 4, thereby optically biasing the photoconductive surface. I'll keep it. On the other hand, after the elapse of time tmc'm<to, as shown in Fig. g4, the first X-ray pulse is applied to the X1lA tube 18 for a time of 1 s. The specimen 9 is exposed to the radiation, and the specimen 90 is
Obtain a transmitted X-ray image of the subject before the angiographic contrast agent flows into the predetermined site, convert it into an optical image at tI・11, and transmit it through the tandem lens 2.3 in the optical system of L1" and m tract 7. An optical image is input to the photoconductive surface as a light pulse.The image pickup tube 7 performs interlace television scanning on the photoconductive surface and outputs a video signal.At this time, the photoconductive surface of the image pickup tube 7 is biased. Since the light has already been irradiated by the light 4, the startup characteristics of the image pickup tube 70 have been compensated for. For example, as shown in FIG. 4, sufficient video output can be obtained by scanning the second field. Since it is an interless system, the video signals of the 2nd and 3rd fields [are output to the digital processor t11, and the A/D
After being converted into a digital signal by a converter, the digital signal is stored in a digital 7-frame memory as a mask image.

Then, after a predetermined period of time has elapsed after the first X@C)@ injection, perform the second and subsequent XIs exposures. At that time,
As in the first X-ray exposure, when the bias light 4 and the photoconductive surface of the image pickup tube 7 are irradiated for a period of 1 tl in advance, the start-up characteristics of the image pickup tube 7 are improved. Leave it, x! ! ! Perform exposure.

Note that the rate of improvement in the rise-up characteristics of the image pickup tube 7 differs depending on the material of the photoconductive surface and the type of image pickup tube. The amount of light may be adjusted as appropriate depending on the type of image pickup tube.

The video signals of the second and third fields obtained by the second and subsequent X@ exposures are output to the digital processor t11 and subjected to subtractive processing in the digital processor 11. A digital video signal as a traction image is obtained, and the subtraction image is displayed on a television monitor 14 via a video output switch 12 or stored in an external memory 15.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above-mentioned embodiment, and may be practiced with appropriate modifications within the scope of the gist of the present invention. Not even.

〔Effect of the invention〕

According to the invention described in detail above, the following effects can be achieved. In other words, since the rise characteristics of the image pickup tube are improved by light irradiation from the bias light, the XII exposure required to rise the signal output of the image pickup tube, which is conventional, is no longer necessary. The exposure time can be shortened, and the safety of the metal specimen against X-ray exposure can be improved.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the original mt of digital 2 geography, Fig. 2 is an explanatory diagram showing the sequence of xlI pulse and video output in a conventional X-ray diagnostic device, and Fig. 3 is an embodiment of the present invention. An explanatory diagram showing an example and FIG. 114 are explanatory diagrams showing the diatance of the X-ray pulse, bias light, and video signal in the above embodiment. 1... Image intensifier, 2, 3...
・Tandem lens, 4...bias light,
7... Image pickup tube, 11-... Digital processor, 1
4... Television monitor (display device), 15... System controller, 17... -X reduced high voltage generator, 18... X-ray tube.

Claims (1)

[Scope of Claims] An X-ray high voltage generator that supplies high voltage to the xIII tube and the %XII+ tube that emit Image f:x
The photoconductive wiK guide (optical system device) of the camera tube in the middle of the TV camera, the X-TV camera that converts the optical II guided by the photoconductive image into a video signal, and the video signal that converts the video signal into a digital signal. At least a true X-ray diagnostic device KTh is installed in the optical system device, and the digital display device and the system controls for controlling each device are installed in the optical system device. Paianutsui)
1, compensate for the rise of the steering tube by irradiating it with a bias light, and then
X-ray exposure IIIt [Characteristics]
#l1lIIl.