JP2000116637A - Image display method and apparatus and fluoroscopic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a display part by displaying an actual image and a control image on a common display device at different timings in the displaying of the actual image of a subject obtained by fluoroscopy and the control image. SOLUTION: During the fluoroscopy, firstly, an X-ray tube 2 is driven by an irradiation control part 12 before the injection of a contrast medium to take a fluoroscopic image of a subject 8 by a video camera 6 and an image data of the fluoroscopic image is stored into a frame memory while being sent to a display part 16 through a switch gear to be displayed as fluoroscopic image. In this process, the fluoroscopic image is displayed in a circular frame and an operator operates an operating part 20 to store the image into a mask memory as mask image. Then, the contrast medium is injected into the subject 8 to take a fluoroscopic image and an image data of the fluoroscopic image taken is stored into the frame memory likewise while a fluoroscopic image containing a blood vessel image clarified by the contrast medium is shown on a display part 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display method and apparatus, and a radiographic apparatus, and more particularly, to an image display method and apparatus for displaying a real image and a reference image obtained by imaging a subject through radiation. The present invention relates to a radiographic apparatus having such an image processing apparatus.

[0002]

2. Description of the Related Art As an example of a radiographic apparatus, for example, DR (digital radiography) is known.
There is a device. In the DR device, X-rays are used as radiation. Then, a cone-shaped X-ray beam (beam) encompassing the imaging range from the X-ray irradiation device.
And illuminates the fluoroscopic image with an image intensifier (II: image intensifier).
r) to convert it to a fluorescent image, and convert it to a video camera (video)
o camera) and shoot on CRT display (c
The information is displayed on a display such as an "ath-ray tube display".

[0003] A perspective image taken by a video camera is converted into a digital image so that various image processing such as storage in a memory and calculation between a plurality of images can be performed. One form of image processing is subtraction processing, and digital subtraction angiography (digital subtraction an) is used for shooting using the subtraction processing.
giography (DSA).

[0004] In this method, angiographic imaging is performed, and a difference between fluoroscopic images of the same site before and after the injection of a contrast agent is obtained to obtain a fluoroscopic image including only blood vessels in which the contrast agent is distributed. Specifically, a perspective image taken in a state where a contrast agent is injected is used as a live image, and a perspective image taken in a state where no contrast agent is injected is used as a mask image. , And an image is formed by the difference between the pixel values. As a result, the image common to the two images disappears by the subtraction, and only the blood vessel part in which a difference has occurred due to the contrast agent is imaged.

[0005] The DR device uses two displays, one displays a live image and the other displays a mask image or a difference image as a reference image (reference: reference). An operation of a catheter is performed.

[0006]

As described above, the radiographic imaging apparatus using two display devices has a problem that the display unit becomes large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide an image display method and apparatus capable of reducing the size of a display unit, and a radiation having such an image display apparatus It is to realize a fluoroscopic apparatus.

[0008]

(1) According to a first aspect of the invention for solving the above-mentioned problems, in displaying a real image and a reference image obtained by imaging a subject through radiation, the real image and the reference image are displayed. An image display method characterized in that images are displayed on a common display at different times.

(2) A second invention for solving the above-mentioned problems is an image display device for displaying a real image and a reference image obtained by imaging a subject through radiation, wherein the real image and the reference image are displayed. Is displayed on a common display at different times.

(3) A third invention for solving the above-mentioned problems is a radiographic imaging apparatus for displaying a real image and a reference image obtained by radiographing a subject with radiation, wherein the real image and the reference image are displayed. A radiographic imaging apparatus comprising: display means for displaying images on a common display at different times.

(4) A fourth aspect of the present invention for solving the above-mentioned problems is that the real image is a perspective image taken in a state where a contrast agent is injected, and the reference image is a perspective image and a contrast image taken in a state where no contrast agent is injected. The radiographic imaging apparatus according to claim 3, wherein the radiographic imaging apparatus is one of a difference image between a fluoroscopic image captured in a state where the agent is injected and a fluoroscopic image captured in a state where the contrast agent is not injected.

[0012] In any one of the first to fourth aspects of the present invention, it is preferable that the display time of the real image is at least set to the fluoroscopic time by the radiation in order to perform appropriate fluoroscopy.

In any one of the first to fourth aspects of the present invention, it is preferable that the real image and the reference image are alternately displayed in order to facilitate comparison between the two images.

(Operation) In the present invention, the actual display image and the reference image are displayed on a common display at different times, so that only one display is required.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiment. FIG. 1 shows a block diagram of the DR device. This apparatus is an example of an embodiment of the radioscopic imaging apparatus of the present invention. The configuration of the present apparatus shows an example of an embodiment relating to the apparatus of the present invention. An example of an embodiment of the method of the present invention is shown by the operation of the present apparatus.

As shown in FIG. 1, the present apparatus has an X-ray tube 2 and an image intensifier (II) 4.
X-ray tube 2 and I. I. Reference numerals 4 are supported by support means (not shown), and are opposed to each other with a space therebetween.
I. I. A video camera 6 is attached to 4.

The X-ray tube 2 and I. I. In the space where 4 faces,
For example, the head of the subject 8 is inserted.
The subject 8 injects a contrast medium into a blood vessel using a contrast medium injection device (not shown) to perform angiographic imaging.

The X-ray tube 2 is connected to an irradiation control unit 12, and under the control of the X-ray tube 2, I.D. I. An X-ray beam 10 having, for example, a conical (cone) shape is radiated toward 4. A perspective image of the head of the subject 8 by the X-ray beam 10 is I. I. 4 is projected on the plane of incidence. I. I. 4 produces a fluorescent image corresponding to the perspective image projected on the plane of incidence and enhances its brightness. A fluorescent image with increased brightness is captured by the video camera 6.

The video camera 6 is connected to the input side of the image processing section 14. A display unit 16 is connected to an output side of the image processing unit 14. The image processing unit 14 processes a video signal input from the video camera 6 to generate a display image, and provides the display image to the display unit 16 for display.

The image processing section 14 is an example of an embodiment of the display means in the present invention. The display unit 16 is an example of the embodiment of the display device according to the present invention. Image processing unit 1
The portion including the display unit 4 and the display unit 16 is an example of an embodiment of the image display device of the present invention.

The irradiation controller 12, the image processor 14, and the display 16 are connected to a controller 18. The control unit 18 supplies a control signal to each unit to control each operation. An operation unit 20 is connected to the control unit 18 so that an operator can input appropriate commands, information, and the like to the control unit 18. The operation unit 20 includes various operation keys (keys), a keyboard (keyboard), and a movable pointing device such as a track ball. The image processing unit 14, the display unit 16, the control unit 18 and the operation unit 20 constitute an operation console (console) 22.

FIG. 2 is a block diagram of the image processing unit 14. As shown in the figure, the image processing unit 14 is an analog / digital (A / D: analog-to-digital)
l) It has a converter 142 to convert an analog video signal input from the video camera 6 into a digital signal.

The output side of the A / D converter 142 is connected to an input port of a frame memory 144 so that a digital output signal is stored in the frame memory 144. Thus, the perspective image of the subject 8 is stored in the frame memory 144.

An input / output port of the frame memory 144 is connected to a CPU through a data bus 146.
(Central processing unit: central
processing unit) 148. The CPU 148 also has an input / output port of a mask memory 150 and an interface (interfac) via a data bus 146.
e) 152 output ports are connected. CPU14
8 has a main memory (not shown).

The output ports of the frame memory 144 and the mask memory 150 are connected to the input side of the pixel processing circuit 154, and input the respective output data L and M to the pixel processing circuit 154.

The output ports of the frame memory 144 and the mask memory 150 are connected to the input side of a switch 156 to output the respective output data L and M to the switch 156.
To be entered.

The output side of the pixel processing circuit 154 is connected to the switch 15
6 to input the output data D to the switch 156. The switch 156 selects any one of the three types of input data by switching. Switching of the switch 156 is controlled by the CPU 148.

Output data from the switch 156 is input to the display unit 16. The input port of the interface 152 communicates with the control unit 18, and the control signal of the control unit 18 is transmitted to the CPU 1.
48 can be input.

The mask image is stored in the mask memory 150. The mask image is created based on the perspective image of the subject 8. The CPU 148 reads the image of the frame memory 144 and the mask image of the mask memory 150 for each pixel, and inputs them to the pixel processing circuit 154. Pixel processing circuit 1
54 outputs the pixel value D by performing the following operation on the pixel value L and the pixel value M.

[0030]

(Equation 1)

Here, C: constant value By the calculation based on the equation (1), the pixel processing circuit 154
A pixel value having a value obtained by subtracting the pixel value M from the pixel value L and adding a constant value C is output. The constant value C is an appropriate value such as an intermediate value of the gradation range of the image. Note that the intermediate value of the gradation range does not necessarily mean the center value of the gradation range.

The operation of the present apparatus will be described. The present device operates under the control of the control unit 18. First, a fluoroscopic image of the subject 8 is taken in a state where the contrast agent has not been injected. The image data of the captured perspective image is stored in the frame memory 144. The image data in the frame memory 144 is provided to the display unit 16 through the switch 156 that has been switched to the L side, and is displayed as an image.

Thus, for example, a perspective image 40 as shown in FIG. 3 is displayed on the screen 162 of the display unit 16. The screen 162 corresponds to the range of the visual field of the video camera 6. The perspective image 40 is displayed in a circular frame 42. Circular frame 42
Is I. I. 4 corresponds to the contour of the incident surface. The operator operates the operation unit 20 to store such an image in the mask memory 150 as a mask image.

Next, a contrast medium is injected into the subject 8 and a fluoroscopic image is taken. The image data of the captured perspective image is stored in the frame memory 144. The image data of the frame memory 144 is provided to the display unit 16 through the switch 156 that has been switched to the L side. For example, as shown in FIG.
A fluoroscopic image 4 including a blood vessel image 48 defined by a contrast agent
0 'is obtained.

When such a perspective image 40 ′ is displayed live (live
e) The pixel processing circuit 154 performs the above-described calculation for each pixel using the image of the mask memory 150 as a mask image as an image. A live image is an example of an embodiment of a real image in the present invention.

That is, the live image shown in FIG.
With respect to the mask image shown in (1), for example, from the upper left corner, calculation is performed for each pixel having the same relative position on the screen according to equation (1).

In the equation (1), LM represents the pixel value of the difference image between the live image and the mask image. By adding C to it and giving a bias, the L-
Even when M is negative, a halftone pixel value that can be displayed by the display unit 16 is obtained.

When the switch 156 is switched to the D side to provide the output data D as described above to the display unit 16, the displayed image is, for example, as shown in FIG. 5, a subtraction image, that is, a blood vessel into which the contrast agent is injected. An image showing only image 48 is displayed. The subtraction image is an example of the embodiment of the reference image in the present invention.

When the switch 156 is switched to the M side to provide the output data M of the mask memory 150 to the display section 16,
As the display image, for example, a mask image as shown in FIG. 3 is displayed. The mask image is an example of the embodiment of the reference image in the present invention.

As described above, the live image, the subtraction image, and the mask image are displayed on the display unit 16 according to the switching of the switch 156. The operator performs the injection of the contrast agent while observing the live image in a state where the switch 156 is switched to the L side, and switches the switch 156 to the D side or the M side as appropriate to obtain the subtraction image or the mask image. Is displayed as a reference for diagnosis and catheter operation.

At this time, the switching of the display is automated. For example, as shown in FIG. 6, the live image L is displayed during the fluoroscopy of the subject 8, and the mask image M is displayed when the fluoroscopy is stopped. good. Thus, a live image is always displayed during fluoroscopy, so that diagnosis and catheter operation can be performed appropriately.

As shown in FIG. 7, the live image L and the subtraction image D may be periodically displayed by automatic switching during the fluoroscopic period, or as shown in FIG. 8, during the fluoroscopic period. The live image L may be displayed first, and thereafter, the mask image M and the subtraction image D may be alternately displayed at an appropriate cycle. This makes it possible to observe the distribution state of the contrast agent over time based on the subtraction image while appropriately referring to the mask image.

As described above, the live image, which is a photographed image, and the mask image or the subtraction image, which is a reference image, are switched and displayed on the common display unit 16, so that the display unit has one display unit. The configuration can be reduced in size or simplified.

Further, since the number of the display units is one, the volume of the display unit 16 is reduced by half as compared with a conventional display unit requiring two display units. The operation console 22 occupying a large part can be reduced in size.

Although an example of angiographic imaging has been described above, it goes without saying that the present apparatus can be used not only for blood vessels but also for imaging other organs such as the ureter. Also, an example using X-rays as radiation has been described.
The radiation is not limited to rays, but may be other types of radiation such as gamma rays. However, at present, X-rays are preferable because practical means regarding generation, detection, control, and the like are the most substantial.

[0046]

As described above in detail, according to the present invention, an image display method and apparatus capable of reducing the size of a display unit, and a radiographic imaging apparatus having such an image display apparatus are realized. can do.

[Brief description of the drawings]

FIG. 1 is a block diagram of a device according to an example of an embodiment of the present invention.

FIG. 2 is a block diagram of an image processing unit in the apparatus according to the embodiment of the present invention;

FIG. 3 is a schematic diagram of an image photographed by an apparatus according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of an image photographed by an apparatus according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of an image captured by an apparatus according to an embodiment of the present invention.

FIG. 6 is a time chart of an operation of the apparatus according to the embodiment of the present invention;

FIG. 7 is a time chart of an operation of the apparatus according to the embodiment of the present invention;

FIG. 8 is a time chart of an operation of the apparatus according to the embodiment of the present invention;

[Explanation of symbols]

 2 X-ray tube 4 Image intensifier 6 Video camera 8 Subject 10 X-ray beam 12 Irradiation control unit 14 Image processing unit 16 Display unit 18 Control unit 20 Operation unit 22 Operation console 142 A / D converter 144 Frame memory 148 CPU 150 Mask memory 154 Pixel operation circuit 156 Switch

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4C093 AA16 AA24 CA32 DA02 EB02 FF34 FG20 5B057 AA08 BA03 CH18 DA04 DA16 5C054 AA01 CA02 CC01 EA05 EB05 FA01 FC12 FE09 FE21 GA04 GB02 GB12 GB15 HA12

Claims (4)

[Claims] When displaying a real image and a reference image obtained by imaging a subject through radiation, the real image and the reference image are displayed on a common display at different times. Image display method to be used. 2. An image display device for displaying a real image and a reference image obtained by radiographing a subject through radiation, wherein the real image and the reference image are displayed on a common display at different times. An image display device comprising: a display unit. 3. A radiographic imaging apparatus for displaying a real image and a reference image obtained by radiographing a subject with radiation, and displaying the real image and the reference image on a common display at different times. A radiographic imaging apparatus comprising: 4. The real image is a perspective image taken in a state where a contrast agent is injected, and the reference image is a perspective image taken in a state where a contrast agent is not injected, a perspective image taken in a state where a contrast agent is injected, and a non-injection state of a contrast agent. The radiographic imaging apparatus according to claim 3, wherein the radiographic imaging apparatus is any one of a difference image from a fluoroscopic image captured in the state.