JP6918487B2 - X-ray image diagnostic device and control method of X-ray image diagnostic device - Google Patents

Description

An embodiment of the present invention relates to an X-ray image diagnostic apparatus and a control method for the X-ray image diagnostic apparatus.

In the X-ray image diagnostic apparatus, an X-ray image based on the X-ray transmitted through the subject is imaged. If foreign matter such as dust or dirt is present in the irradiation path to which the X-ray is irradiated, the X-ray is absorbed by the foreign matter. The absorption characteristics of X-rays by this foreign substance are very similar to the absorption characteristics of X-rays in tumors, calcifications, mammary glands, etc. in the subject. Therefore, if a foreign substance is present in the irradiation path, a tumor, calcification, mammary gland, or the like that does not actually exist is imaged as if it were present in the subject.

During the cleaning performed to prevent the imaging of the foreign matter, an X-ray image is taken without placing the subject. When a foreign substance is present in the irradiation path, the region that receives the X-ray that has passed through the foreign substance is imaged as a shadow. Based on this shadow, the presence of foreign matter in the irradiation path is confirmed.

However, in the X-ray detector, defective pixels that output pixel values different from those of other pixels may occur, and the image signal output by the defective pixels is also imaged as a shadow. Therefore, in one X-ray image, shadows caused by defective pixels and shadows caused by X-rays transmitted through foreign substances may coexist, making it difficult to confirm the presence of foreign substances. ..

Japanese Patent No. 5526062

An object of the present embodiment is to provide an X-ray image diagnostic apparatus capable of determining the cause of occurrence of feature pixels, and a control method for the X-ray image diagnostic apparatus.

The X-ray diagnostic apparatus according to the present embodiment includes an irradiation unit capable of irradiating X-rays under a plurality of irradiation conditions, an X-ray detector that detects the X-rays emitted from the irradiation unit, and the X-rays. An image generation unit that generates an X-ray image based on the X-rays detected by the detector, a feature pixel detection unit that detects feature pixels whose pixel values in the X-ray image are different from other pixel values, and the above. It is provided with a discriminating unit for determining the cause of occurrence of the feature pixels based on changes in the feature pixels between the X-ray images generated by a plurality of irradiation conditions.

The figure which shows the structural example of the X-ray image diagnostic apparatus. The figure which shows the state which the arm is rotating about the support shaft as a rotation center. The block diagram which shows the structure of the information processing apparatus which concerns on 1st Embodiment. FIG. 4A is a diagram showing a case where the cause of generation of feature pixels is an X-ray detector. FIG. 4B is a diagram showing a case where the cause of the feature pixels is in the photographing table. FIG. 4C is a diagram showing a case where the cause of the characteristic pixels is the compression plate. FIG. 4D is a diagram showing a case where the cause of the characteristic pixels is the beam filter. FIG. 4 (e) is a diagram showing a case where the cause of generation of feature pixels is one of the beam filters. The figure which shows the relationship between the movement amount of a feature pixel, and the position of a unit. FIG. 6A is a diagram showing a case where the cause of generation of characteristic pixels is the support surface of the photographing table or the surface of the compression plate. FIG. 6B is a diagram showing a case where the cause of the feature pixels is on the surface of the beam filter. The figure which shows the example which changes the beam filter and changes the irradiation position of an irradiation apparatus. The figure which shows the flowchart which showed the series flow of the imaging control in an inspection mode. The figure which shows the flowchart explaining an example of the algorithm of the discriminant function which discriminates whether or not there is a cause of occurrence of a characteristic pixel in a beam filter. The figure which shows the flowchart explaining an example of the algorithm of the discriminant function which discriminates whether or not there is the occurrence cause of a characteristic pixel in the X-ray irradiation path. The figure which shows the example which changes the beam filter for each irradiation position of an irradiation apparatus. The figure which shows the flowchart which showed the series flow of the photographing control which concerns on 2nd Embodiment. The block diagram which shows the structure of the information processing apparatus which concerns on 3rd Embodiment. The figure which shows an example of a foreign matter table and a scratch table. The figure which shows an example of the defect table. FIG. 16A is a diagram showing the position of foreign matter on the beam filter. FIG. 16B is a diagram showing the position of foreign matter on the compression plate. FIG. 16 (c) is a diagram showing the position of foreign matter on the compression plate. FIG. 17A is a diagram showing the positions of scratches on the beam filter. FIG. 17B is a diagram showing the positions of scratches on the compression plate. FIG. 17C is a diagram showing the positions of scratches on the compression plate. FIG. 18A is a diagram showing the positions of foreign matter and scratches on the beam filter. FIG. 18B is a diagram showing the positions of foreign matter and scratches on the compression plate. FIG. 18C is a diagram showing the positions of foreign matter and scratches on the compression plate. It is a mixed map of foreign matter and scratches generated by the generation function, and is a diagram reflecting the height in the Z-axis direction. A diagram of a foreign matter map showing the positions of foreign matter on a schematic diagram of the actual machine. The figure which shows the defect point map generated by the generation function. The figure of the first half which shows the flowchart explaining the algorithm of the discrimination function which discriminates whether or not the cause of occurrence of a feature pixel is a scratch. The latter half of the figure which shows the flowchart explaining the algorithm of the discrimination function which discriminates whether or not the cause of occurrence of a feature pixel is a scratch. The figure which shows the flowchart explaining the algorithm of the generation function in a processing circuit.

Hereinafter, the X-ray image diagnostic apparatus 1 according to the embodiment will be described with reference to the drawings. In the following description, components having substantially the same function and configuration are designated by the same reference numerals, and duplicate explanations will be given only when necessary.

(First Embodiment)
First, the overall configuration of the X-ray image diagnostic apparatus 1 will be described with reference to FIG. FIG. 1 is a diagram showing a configuration example of the X-ray image diagnostic apparatus 1. As shown in FIG. 1, the X-ray diagnostic imaging apparatus 1 is an apparatus capable of photographing a breast from a plurality of positions, and includes an mammography apparatus 100, an information processing apparatus 200, an input circuit 300, a display 400, and the like. It is configured to include an exposure button 500 and a high voltage generator 600. Further, here, the axes indicating the coordinates on the horizontal plane are the X-axis and the Y-axis, and the vertically upper axis is the Z-axis.

The mammography apparatus 100 is an apparatus that X-rays the breast of a subject from a plurality of directions within a limited angle range. The information processing device 200 is composed of, for example, a computer, and controls the entire X-ray image diagnostic device 1 and acquires information such as a foreign substance in the mammography device 100. Details of the mammography apparatus 100 and the information processing apparatus 200 will be described later.

The input circuit 300 is realized by a trackball, a switch button, a mouse, a keyboard, or the like for setting an inspection mode or the like. The input circuit 300 is connected to the information processing device 200, converts the input operation received from the inspector into an electric signal, and outputs the input operation to the information processing device 200.

The display 400 is realized by a liquid crystal display device or the like for displaying an X-ray image and various kinds of information. More specifically, the display 400 is connected to the information processing device 200, converts an image processed by the information processing device 200 into a luminance signal, and displays the image on the screen.

The exposure button 500 is a switch for instructing the information processing apparatus 200 of the X-ray irradiation timing, and the inspector manually operates the exposure button 500. The exposure button 500 is connected to the information processing device 200, and when the inspector presses the switch, the exposure start signal is output to the information processing device 200.

The high voltage generator 600 outputs the tube voltage and the filament current. The high voltage generator 600 is connected to the information processing device 200 and the mammography apparatus 100, and supplies the tube voltage and the filament current to the mammography apparatus 100 according to the imaging condition signal output by the information processing apparatus 200.

Next, the details of the mammography apparatus 100 will be described. The mammography apparatus 100 is a device capable of tomosynthesis imaging and biopsy positioning imaging, and includes a base 102, a stand 104, an arm 106, a support shaft 108, a support plate 110, an irradiation device 112, and a rotary motor. It is configured to include 122, an imaging table 124, a compression plate 126, an elevating motor 128, an elevating mechanism 130, an X-ray detector 132, and an image generation circuit 134. Here, breast tomosynthesis imaging is an imaging technique for obtaining a three-dimensionally reconstructed tomographic image using an X-ray drawing of a breast in a state of being compressed from a plurality of directions within a limited angle. In addition, breast biopsi is one of the clinical tests in which the lesion tissue in the breast is collected with a needle and the lesion tissue is observed and diagnosed with a microscope. In this biopsi positioning imaging, the breast is imaged from a plurality of directions in order to position the lesion tissue.

The base 102 mounts the entire mammography apparatus 100. The stand 104 is erected on the base 102 and supports the arm 106. One end of the support shaft 108 is fixed to the stand 104, and the other end of the support shaft 108 fixes and supports the support plate 110. That is, the arm 106 has a hole through which the support shaft 108 penetrates, and is rotatably supported by the stand 104 through the hole. An irradiation device 112 is provided at the upper end of the arm 106.

The irradiation device 112 irradiates the subject with X-rays. That is, the irradiation device 112 irradiates the subject with X-rays while changing the X-ray irradiation direction according to the rotation of the arm 106 about the support shaft 108 as the rotation center. The irradiation device 112 includes an X-ray tube 114, an X-ray movable diaphragm 116, a plurality of beam filters 118, and a change motor 120.

The X-ray tube 114 generates X-rays. More specifically, the X-ray tube 114 is connected to the high voltage generator 600 and outputs X-rays corresponding to the tube voltage and filament current supplied from the high voltage generator 600. That is, the X-ray tube 114 generates X-rays based on the imaging condition signal input from the information processing device 200 to the high voltage generator 600. More specifically, the X-ray tube 114 generates higher energy X-rays whose wavelength peaks are shifted to the shorter wavelength side as the supplied tube voltage increases. Also, the X dose is proportional to the filament current. Therefore, the tube voltage and the filament current are adjusted according to the thickness of the subject and the like. A so-called small focal point is used as the focal point for generating X-rays in the X-ray tube 114.

The X-ray movable diaphragm 116 has a pinnate diaphragm made of lead or the like. The X-ray movable diaphragm 116 is arranged at the outlet of the X-ray tube 114, and is limited by moving the diaphragm of the X-ray irradiation range generated by the X-ray tube 114. As a result, the X-rays irradiated to the subject are limited, so that unnecessary exposure to the subject and scattered X-rays from the portion can be reduced.

The beam filter 118 is, for example, a rectangular plate, and is made of copper, aluminum, or the like. Here, a plurality of types of beam filters 118 are used. These beam filters 118 are arranged at the emission port of the X-ray movable diaphragm 116, and change the wavelength spectrum of the X-ray more finely. For example, the beam filter 118 is changed according to the size and thickness of the subject. In this way, in addition to the wavelength adjustment of X-rays by changing the tube voltage, finer wavelength adjustment using the beam filter 118 can be performed. Therefore, the irradiation device 112 can irradiate X-rays having a wavelength more suitable for mammography of the subject by using the beam filter 118.

The change motor 120 changes the beam filter 118 used for photographing through the change mechanism. More specifically, the change motor 120 is connected to the information processing device 200 and changes the beam filter 118 according to the change signal output by the information processing device 200. That is, the selection signal input by the inspector via the input circuit is output to the information processing device 200, and the change signal based on the selection signal is input from the information processing device 200 to the change motor 120. As a result, the beam filter 118 used for imaging is changed to the beam filter 118 selected by the inspector.

The rotary motor 122 rotates the arm 106 with the support shaft 108 as the center of rotation. That is, the support shaft 108 serves as the rotation center axis of the X-ray tube 114 in tomosynthesis imaging and positioning imaging in biopsi. More specifically, the rotary motor 122 is connected to the information processing device 200 and rotates the arm 106 according to the rotation signal output by the information processing device 200. As a result, the irradiation position of the irradiation device 112 provided at the upper end of the arm 106 is changed, and the breast of the subject can be automatically irradiated with X-rays from different directions.

As described above, the support plate 110 is fixedly supported by the stand 104 via the support shaft 108. An imaging table 124 is provided at the lower end of the support plate 110. The imaging table 124 is a table that supports the breast of the subject, and has a support surface on which the breast is placed. Further, the support plate 110 supports the compression plate 126 arranged above the photographing table 124 so as to be movable in the vertical direction. The compression plate 126 faces the imaging table 124 in parallel and presses the breast of the subject supported by the imaging table 124. By compressing the breast, the overlap of the mammary glands and the like is reduced, and it becomes possible to take an X-ray image more suitable for diagnosis.

The elevating motor 128 is provided at the end of the support shaft 108, and elevates the compression plate 126 up and down via the elevating mechanism 130. More specifically, the elevating motor 128 is connected to the information processing device 200 and elevates the compression plate 126 according to the elevating signal output by the information processing device 200. In this way, when the elevating motor 128 moves the compression plate 126 in the direction approaching the imaging table 124, the breast of the subject supported on the imaging table 124 is compressed.

An X-ray detector 132 and an image generation circuit 134 are provided inside the photographing table 124. The X-ray detector 132 is composed of a plane detector (FPD: Flat Panel Detector) for detecting X-rays applied to the detection surface. The FPD has an image sensor, and the image sensor includes a CMOS image sensor (Complementary Metal Oxide Semiconductor Image Sensor), a CCD (Charge Coupled Device), and a thin film transistor (TFT: thin film) together with a photoconductive film and a phosphor. Etc. are used in combination.

More specifically, the X-ray detector 132 is connected to the information processing device 200 and is controlled according to, for example, a storage signal and an irradiation time signal input from the information processing device 200. For example, in a CMOS image sensor, according to an accumulated signal, a photodiode (PD) constituting each pixel detects light converted by a fluorescent film while X-rays are emitted from an X-ray tube 114. Stores charge according to X-ray dose. Then, according to the irradiation time signal, each of these pixels converts the stored charge into a voltage according to the end of the irradiation time, and outputs the voltage signal amplified by the amplifier as an analog image signal.

The image generation circuit 134 converts an analog signal into a digital signal. More specifically, the image generation circuit 134 is connected to the X-ray detector 132 and the information processing device 200, and converts an analog image signal input from the X-ray detector 132 into a digital image signal. The image generation circuit 134 outputs this digital image signal as an image signal of an X-ray image to the information processing apparatus 200.

Further, the X-ray image diagnostic apparatus 1 of the present embodiment has a normal photographing mode and an inspection mode. In the normal imaging mode, tomosynthesis imaging, biopsi positioning imaging, and the like are performed while the breast of the subject placed on the imaging table 124 is compressed by the compression plate 126.

On the other hand, in the examination mode, X-rays irradiated from a plurality of predetermined irradiation positions are imaged without placing the breast of the subject on the imaging table 124. Based on the X-ray image taken without placing these subjects on the imaging table 124, foreign matter, scratches, defective pixels, etc. in the mammography apparatus 100 described later are detected.

Here, the foreign matter is dust, dust, or the like adhering to the inside of the mammography apparatus 100, and is a substance that interferes with the image diagnosis. When foreign matter is detected, it is removed by cleaning.

The scratches are crevices formed on the surfaces of the beam filter 118, the compression plate 126, the photographing table 124, and the X-ray detector 132, and mean places that hinder image diagnosis. When a scratch is detected, it is removed by repair or replacement of a unit.

The defective pixel means a pixel that outputs a feature pixel value when the same X-ray dose is applied to each pixel in the X-ray detector 132. The feature pixel value here means a pixel value different from the pixel value output by another pixel. In other words, the defective pixel means a pixel that outputs a pixel value significantly different from the pixel value output by other pixels when the same X-ray dose is applied to each pixel in the X-ray detection device. Further, in the present embodiment, the position of the defective pixel is referred to as a defective point. Defective pixels are caused, for example, by malfunction of the photodiodes constituting the pixels or wiring defects. Therefore, even if the defective pixel receives X-rays, it may output an image signal having a value smaller than a predetermined value, output an image signal having a large value, or may not output an image signal. As will be described later, the pixel value of the defective pixel is corrected.

The mammary gland is a tissue in the breast. The breast is mainly composed of mammary glands and fat. A mass is a mass in the breast that is made up of a composition that is slightly different from the mammary glands and fat. A tumor is diagnosed as benign or malignant based on its shape, concentration, margin (surrounding border), and the like. In calcification, blood vessels, ducts, or a part of a lesion change, and the image is taken as a stone in an X-ray image. Calcification is diagnosed as benign or malignant depending on its morphology and distribution in the breast.

Next, a plurality of irradiation positions in the mammography apparatus 100 will be described with reference to FIG. FIG. 2 is a diagram showing a state in which the arm 106 is rotating about the support shaft 108 as the center of rotation. Here, the center of the support shaft 108 is indicated by a point. As shown in FIG. 2, the rotary motor 122 rotates the arm 106 according to the rotation signal output by the information processing device 200. As a result, the information processing device 200 changes the position of the irradiation device 112 provided at the end of the arm 106. In the inspection mode, X-rays are emitted from the irradiation device 112 at a plurality of angles, for example, angles −θ, 0, and θ degrees.

Next, the configuration of the information processing apparatus 200 will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the information processing apparatus 200 according to the first embodiment. The information processing device 200 includes a first storage circuit 202, a control circuit 204, a second storage circuit 206, and a processing circuit 208.

The first storage circuit 202 has a configuration including a readable recording medium such as a magnetic or optical recording medium or a semiconductor memory. The first storage circuit 202 stores each processing function performed by the control circuit 204 and the processing circuit 208 in a program form that can be executed by a computer. It also stores various data used in the X-ray diagnostic imaging apparatus 1.

The control circuit 204 is a processor that realizes each control function corresponding to each program by reading a program from the first storage circuit 202 and executing the program. In other words, the control circuit 204 in the state where each program is read has each processing function. Although it has been described in FIG. 3 that each processing function is realized by a single control circuit 204, the control circuit 204 is configured by combining a plurality of independent processors, and each processor executes a program. Each processing function may be realized by.

More specifically, the control circuit 204 includes an imaging control function 210, a rotation control function 212, a change control function 214, and an elevating control function 216, and the modification motor 120 of the mammography apparatus 100. , The rotary motor 122, the elevating motor 128, the X-ray detector 132, the image generation circuit 134, the processing circuit 208, the input circuit 300, the display 400, the exposure button 500, and the high voltage generator 600. It is connected to and so on to control the entire X-ray image capturing device.

The imaging control function 210 controls the overall imaging timing of the X-ray image diagnostic apparatus 1 and controls each function. That is, the photographing control function 210 also controls the processing circuit 208.

As described above, the rotation control function 212 controls the rotation motor 122 in accordance with the control of the photographing control function 210. More specifically, the rotation of the rotary motor 122 is controlled so that the irradiation device 112 is located at the imaging position indicated by the imaging control function 210.

The change control function 214 controls the change motor 120 in accordance with the control of the photographing control function 210. More specifically, the change control of the beam filter 118 is performed so that the beam filter 118 instructed by the imaging control function 210 is arranged at a position where the X-rays emitted by the irradiation device 112 are transmitted.

The elevating control function 216 controls the elevating of the elevating motor 128 in accordance with the control of the photographing control function 210. More specifically, the elevating control of the compression plate 126 is performed so that the compression plate 126 is located at the position indicated by the photographing control function 210. In this case, the elevating control function 216 controls the load of the elevating motor 128 so that the pressure applied to the breast of the subject is within a predetermined range.

The second storage circuit 206 stores information on the above-mentioned foreign matter, scratches, and defective points. The second storage circuit 206 has a configuration including a readable recording medium such as a magnetic or optical recording medium or a semiconductor memory. That is, the second storage circuit 206 includes a foreign matter table 218, a scratch table 220, and a defect point table 222. The foreign matter table 218 is a general garbage table, and stores at least the position coordinates of the foreign matter and the date and time of occurrence. The scratch table 220 stores at least the position coordinates of the scratch and the date and time of occurrence. The defect point table 222 stores at least the position coordinates of the defect points and the date and time of occurrence.

The processing circuit 208 is a processor that realizes each control function corresponding to each program by reading a program from the first storage circuit 202 and executing the program. That is, the processing circuit 208 includes an image processing function 224, an acquisition function 226, a feature pixel detection function 228, a discrimination function 230, and a coordinate conversion function 231.

The image processing function 224 is connected to the image generation circuit 134 and preprocesses the X-ray image. For example, the image processing function 224 applies shading correction processing, sensitivity correction processing, defect point correction processing, and the like to an X-ray image as preprocessing. The shading correction process is a process for correcting the pixel value of the X-ray image, and is a process for correcting the variation in the X-ray intensity distribution caused by the arrangement of the irradiation device 112 and the X-ray detector 132. As a result, even if the intensity of the X-rays emitted from the irradiation device 112 to the X-ray detector 132 is not uniform, it is possible to obtain an X-ray image equivalent to the case of irradiating the X-rays with the uniform intensity. be.

The sensitivity correction process is a process of correcting a pixel value of an X-ray image, and is a process of equalizing the sensitivity of each pixel in the X-ray detector 132. By this sensitivity correction processing, even if the pixel sensitivity in the X-ray detector 132 is non-uniform, it is possible to obtain an X-ray image equivalent to an X-ray image captured by pixels having uniform sensitivity.

The defect point correction process is a process of correcting the pixel value of the defective pixel with the pixel value around the defective pixel by using the information in the defect point table 222. For example, the defect point correction process is a process in which the average value of the pixel values within a predetermined range from the defective pixel is set as the pixel value of the defective pixel. As a result, the pixel value of the defective pixel becomes equal to the value proportional to the average value of the X dose received by the pixel within a predetermined range from the defective pixel.

In addition, the image processing function 224 has a function of reconstructing a tomographic image of the breast of the subject. That is, in the normal radiography mode, the image processing function 224 reconstructs the breast tomographic image based on a plurality of X-ray images having different irradiation angles. The X-ray image here is subjected to the above-mentioned preprocessing.

The acquisition function 226 is connected to the control circuit 204 and the first storage circuit 202, and acquires system information regarding the imaging state of the mammography apparatus 100 based on the control signal output by the control circuit 204. That is, the acquisition function 226 acquires the type of the beam filter 118 used for photographing, the angle of the arm 106, and the position of the compression plate 126. Further, the acquisition function 226 stores the system information in the first storage circuit 202 in association with the X-ray image.

Further, the acquisition function 226 calculates the position coordinates on the surface of the beam filter 118 and stores them in the first storage circuit 202 in advance. These position coordinates are used by the discrimination function 230 when the position coordinates of foreign matter or the like on the surface of the beam filter 118 are calculated in detail as described later. For example, the rotation angles −θ, 0, θ (FIG. 2) of the arm 106 in the inspection mode are predetermined. Therefore, the acquisition function 226 calculates the position coordinates on the surface of the beam filter 118 in advance for each of the angles −θ, 0, and θ used in the inspection mode, and stores them in the first storage circuit 202. Similarly, the acquisition function 226 calculates in advance the position coordinates of the irradiation position of the irradiation device 112 at the rotation angles −θ, 0, θ (FIG. 2) and stores them in the first storage circuit 202.

The feature pixel detection function 228 detects feature pixels from the X-ray image preprocessed by the image processing function 224, and outputs the position coordinates of the feature pixels to the discrimination function 230. That is, the feature pixel detection function 228 detects feature pixels whose pixel values in the X-ray image acquired in the inspection mode are different from those of other pixel values. For example, the feature pixel detection function 228 detects pixels having a predetermined value or less, that is, dark pixels as feature pixels. More specifically, the feature pixel detection function 228 calculates the standard deviation σ of the pixel value in the X-ray image preprocessed by the image processing function 224. Then, the feature pixel detection function 228 acquires a pixel value as a predetermined value, which is three times or more smaller than the standard deviation σ of the average pixel value of the X-ray image. As described above, the feature pixel detection function 228 can detect a characteristic pixel whose pixel value in the X-ray image is statistically different from other pixel values as a feature pixel.

The discrimination function 230 discriminates the cause of generation of feature pixels based on changes in feature pixels between X-ray images generated by a plurality of irradiation conditions. That is, the discrimination function 230 acquires the information of the feature pixels detected by the feature pixel detection function 228, and also acquires the system information associated with the X-ray image in which the feature pixels are detected from the first storage circuit 202. Then, the discrimination function 230 discriminates the cause of the occurrence of the feature pixel based on the feature pixel information and the system information.

More specifically, the discrimination function 230 will be described with reference to FIGS. 2 and 4 based on FIGS. 4 to 6. FIG. 4 is a simplified view showing a state in which the arm 106 shown in FIG. 2 is rotating with the support shaft 108 as the center of rotation. Here, the locations T10, T12, T14, T16, T18 where the cause of the feature pixel generation exists, and the positions T10A, T10B, T12A, T12B, T14A, T14B, T16A, T16B, T18B of the feature pixel in the X-ray image. And. Further, among the X-rays emitted by the irradiation device 112, the X-rays that pass through these T10, T12, T14, T16, and T18 are shown by line segments. A and B in FIG. 4 indicate two irradiation positions of the irradiation device 112.

FIG. 4A is a diagram showing a case where the characteristic pixel generation cause T10 is in the X-ray detector 132, and FIG. 4B is a diagram showing a case where the feature pixel generation cause T12 is in the photographing table 124. FIG. 4C is a diagram showing a case where the characteristic pixel generation cause T14 is on the compression plate 126, and FIG. 4D is a case where the feature pixel generation cause T16 is on the beam filter 118f1. 4 (e) is a diagram showing a case where the occurrence cause T18 of the feature pixel is in the beam filter 118f1. In FIG. 4 (e), the beam filters 118f1 and f2 are changed with the irradiation position fixed at B. That is, in FIGS. 4A to 4D, the irradiation positions are changed to two positions, A and B, as irradiation conditions. Further, in FIG. 4E, the beam filter 118f1 is changed to the beam filter 118f2 as an irradiation condition. Here, T10 indicates the position of the defective pixel of the X-ray detector 132, T12 indicates a foreign substance on the photographing table 124, T14 indicates a foreign substance on the compression plate 126, and T16 and T18 indicate a foreign substance on the beam filter 118f1. Indicates the position of. In addition, T12, T14, T16, and T18 may be scratches.

In the example shown in FIG. 4A, the defective pixel T10 in the X-ray detector 132 outputs the feature pixel value. Here, T10A indicates the position of the characteristic pixel value when the irradiation device 112 is irradiating X-rays from the position A, and T10B is the position when the irradiation device 112 is irradiating the line from the position B. Features Indicates the position of the pixel value. In this way, even if the positions A and B of the irradiation device 112 are changed, the positions of the defective pixels T10 that output the feature pixel values do not change, so that the positions T10A and T10B of the feature pixels do not change.

On the other hand, in FIGS. 4 (b) to 4 (d), foreign substances T12, T14, and T16 are present in the irradiation path. In such a case, if the irradiation positions A and B of the irradiation device 112 are changed, the position where the X-ray transmitted through the foreign matter T12, T14, and T16 is irradiated always changes. That is, in the case of the irradiation position A, the position where the X-ray transmitted through the foreign matter T12, T14, T16 is irradiated is the position of the feature pixels T12A, T14A, T16A. On the other hand, in the case of the irradiation position B, the position where the X-ray transmitted through the foreign matter T12, T14, T16 is irradiated is the position of the feature pixels T12B, T14B, T16B.

Here, the X-ray dose of the X-rays that have passed through the foreign substances T12, T14, and T16 is absorbed by the foreign substances T12, T14, and T16. Therefore, the pixel value output by the pixel existing at the position where the X-ray transmitted through the foreign matter T12, T14, and T16 is irradiated is smaller than the other pixel values. In other words, the pixels existing at the positions where the X-rays transmitted through the foreign substances T12, T14, and T16 are irradiated are detected as the feature pixels.

In this way, when foreign matter T12, T14, T16 is present in the irradiation path, if the irradiation positions A and B of the irradiation device 112 are changed, the position of the feature pixel can be changed from the position T12A, T14A, T16A to the position T12B. , T14B, T16B. On the other hand, when the defective pixel T10 outputs the feature pixel value, the feature pixel positions T10A and T10B do not change even if the irradiation position of the irradiation device 112 is changed.

Therefore, the discrimination function 230 states that when the position of the feature pixel changes between the X-ray images generated by the plurality of irradiation positions A and B, the feature pixel is generated in the X-ray irradiation path. Determine. The cause of occurrence in this case is foreign matter T12, T14, T16. For example, in FIG. 4B, when the position of the feature pixel changes from T12A to T12B between the X-ray images generated by the plurality of irradiation positions A and B, the feature pixel is included in the X-ray irradiation path. It is determined that there is T12, which is the cause of the occurrence of.

Further, in the discrimination function 230, when the positions T10A and T10B of the feature pixels do not change between the X-ray images generated by the plurality of irradiation positions A and B, the X-ray detector 132 determines the cause T10 of the feature pixels. Determine if there is. For example, in FIG. 4A, when the positions T10A and T10B of the feature pixels do not change between the X-ray images generated by the plurality of irradiation positions A and B, the feature pixels are generated in the X-ray detector 132. It is determined that there is a cause T10. In this case, the defective pixel T10 is the cause of the occurrence of the feature pixel, and the position coordinates of T10A are equal to the position coordinates of T10B.

Further, as shown in FIG. 4E, when the foreign matter T18 is present on the beam filter 118f1, the pixel value output by the pixel existing at the position where the X-ray transmitted through the foreign matter T18 is irradiated is another pixel value. It is smaller than the pixel value. Therefore, the pixel existing at the position where the X-ray transmitted through the foreign matter T18 is irradiated is detected as the feature pixel T18B. On the other hand, when the beam filter 118f2 is used, the feature pixels are not detected because there is no cause for the feature pixels to be generated.

Therefore, the discrimination function 230 causes the beam filters 118f1 and f2 to generate the feature pixels when the generation of the feature pixels changes between the X-ray images generated in response to the change of the beam filters 118f1 and f2. Determine if there is. That is, the discrimination function 230 determines that the beam filter 118f1 has the cause T18 for generating the feature pixels when the feature pixels are no longer detected by changing the beam filter 118f1 to f2. On the other hand, the discrimination function 230 determines that the beam filter 118f1 has the cause T18 for generating the feature pixels when the feature pixels are detected by changing the beam filter 118f2 to f1. In this way, the discrimination function 230 discriminates the cause of the occurrence of the feature pixels based on the changes in the feature pixels between the X-ray images generated by the plurality of irradiation conditions.

Further, as shown in FIGS. 4 (b) and 4 (c), the movement amounts of the feature pixels when the irradiation position of the irradiation device 112 moves from A to B are D12 and D14, respectively. Further, the amount of movement here has a relationship of D12 <D14. That is, as the T12 and T14 that are the causes of the occurrence move away from the X-ray detector 132, the movement amounts D12 and D14 increase. That is, as the amount of movement of the feature pixel increases with respect to the amount of movement of the irradiation position, the cause of the feature pixel is generated at a position farther from the X-ray detector 132 in the X-ray irradiation path. ..

Therefore, in the discrimination function 230, as the movement amount of the feature pixel becomes larger than the movement amount of the irradiation position, the feature pixel is generated at a position further away from the X-ray detector 132 in the X-ray irradiation path. Determine that there is a cause. That is, it is possible to determine the unit that has the cause of the feature pixel generation based on the movement amount of the feature pixel. However, since the beam filter 118 moves together with the irradiation device 112, the position of the beam filter 118 cannot be determined based on the amount of movement of the feature pixels. Therefore, as shown in FIG. 4 (e), by irradiating X-rays by exchanging the beam filters 118f1 and 118f2, it is possible to identify which beam filter has the cause of the characteristic pixel generation. be.

Further, normally, the line segment connecting the irradiation positions A and B and the detection surface of the X-ray detector 132 are parallel to each other. Further, since the detection surface of the X-ray detector 132, the support surface of the photographing table 124, and the compression plate 126 are parallel, the line segment connecting the irradiation positions A and B and the detection surface of the X-ray detector 132. The support surface of the photographing table 124 and the compression surface of the compression plate 126 are substantially parallel to each other. In this case, for example, in FIG. 4B, the triangle connecting the irradiation positions A and B and the occurrence cause T12 of the feature pixel and the triangle connecting the occurrence cause T12 and the feature pixel positions T12A and T12B have similar figures. Therefore, regardless of where the cause T12 is located on the support surface of the photographing table 124, the amount of movement is substantially the same. In this case, the height from the X-ray detection surface can be uniquely obtained based on the amount of movement.

For example, as shown in FIG. 2, assuming that the position where the arm 106 is −θ is the irradiation position A and the position where the arm 106 is θ is the irradiation position B, the line segment connecting the irradiation positions A and B and X The detection surface of the line detector 132, the support surface of the imaging table 124, and the compression surface of the compression plate 126 are parallel to each other.

FIG. 5 is a diagram showing the relationship between the movement amount of the feature pixels and the position of the unit. Here, the case where the line segment connecting the irradiation position A and the irradiation position B is parallel to the detection surface of the X-ray camera is shown. That is, the height of the X-ray detector 132 from the detection surface can be uniquely obtained based on the amount of movement. Further, the detection surface of the X-ray detector 132 is shown as the origin of the Z axis.

In FIG. 5, the range of the quadrangle shown by B100 indicates the range of the height under the photographing table 124. That is, the range from the detection surface of the X-ray detector 132 to the support surface of the photographing table 124 is shown. The straight line indicated by B200 indicates the height of the surface of the photographing table 124. Furthermore, the square range indicated by B300 indicates the elevating range of the compression surface surface of the compression plate 126.

As shown in FIG. 5, the height range of the compression plate 126 and the imaging table 124 in the mammography apparatus 100 is predetermined. As a result, it can be determined that the cause of the feature pixel is present in the unit corresponding to the height at which the cause of the feature pixel is present. Therefore, the discrimination function 230 generates feature pixels on any of the compression plate 126, the photographing table 124, under the photographing table 124, and the detection surface of the X-ray detector 132 based on the amount of movement of the feature pixels between the X-ray images. It is possible to determine whether the cause exists.

More specifically, when the movement amount is 0, the discrimination function 230 determines that the cause of the occurrence is the "detection surface" of the X-ray detector 132, that is, the pixels of the X-ray detector 132. Further, the discrimination function 230 determines that the cause of occurrence is between the detection surface of the X-ray detector 132 and the surface of the imaging table 124 when the amount of movement is within the range indicated as “under the imaging table”. Similarly, when the amount of movement is within the range indicated as "shooting table", it is determined that the cause of the movement is on the surface of the shooting table 124. Similarly, when the amount of movement is in the range indicated as "compression plate", it is determined that the cause of the movement is the surface of the compression surface of the compression plate 126. In this way, it is possible to determine the unit in which the cause of the abnormal pixel is present only by obtaining the movement amount.

On the other hand, if the amount of movement is within the range indicated as "error", it is determined that the error is the detection of the position of the cause of occurrence. By calculating and defining the range of the movement amount of the feature pixels in advance in this way, it is possible to perform the unit discrimination process and the discrimination error process.

Next, with reference to FIG. 4, the position coordinate calculation function of the discrimination function 230 will be described with reference to FIG. FIG. 6 is a diagram showing the position coordinates of the irradiation device 112 and the feature pixel coordinates. Here, the position is shown in three-dimensional coordinates.

FIG. 6A is a diagram showing a case where the cause of generation of the feature pixels is the support surface of the photographing table 124 or the compression surface surface of the compression plate 126. That is, it is the same figure as FIGS. 4 (b) and 4 (c). Here, L100 indicates a line segment connecting the irradiation position coordinates (xa1, ya1, za1) of the irradiation device 112 and the position coordinates (xa2, ya2, za2) of the feature pixels, and L200 indicates the irradiation of the irradiation device 112. A line segment connecting the position coordinates (xb1, yb1, zb1) and the position coordinates (xb2, yb2, zb2) of the feature pixels is shown.

FIG. 6B is a diagram showing a case where the cause of generation of feature pixels is on the surface of the beam filter 118f1. That is, it is the same figure as the left figure of FIG. 4 (e). Here, L300 indicates a line segment connecting the irradiation position coordinates (xa1, ya1, za1) of the irradiation device 112 and the position coordinates (xa3, ya3, za3) of the feature pixels.

As shown in FIG. 6A, the intersection of the line segment L100 and the line segment L200 becomes the position coordinates (xT20, yT20, zT20) of the occurrence cause T20 of the feature pixel. Therefore, the discrimination function 230 can discriminate the position coordinates of the foreign matter based on the combination of the position of the irradiation device 112 and the position of the corresponding feature pixel. However, as shown in FIG. 4D, for example, when the cause of the feature pixels is on the surface of the beam filter 118, the beam filter 118 moves together with the X-ray tube 114, so that the position of the irradiation device 112 and the position of the irradiation device 112 It is not possible to determine the position coordinates of a foreign object based on the combination with the position of the corresponding feature pixel.

Therefore, as shown in FIG. 6B, the discrimination function 230 acquires the position coordinates of the surface of the beam filter 118f1 stored in the first storage circuit 202. Then, the discrimination function 230 calculates the intersection of the position coordinates of the surface of the beam filter 118 and the line segment L300 as the position coordinates (xT22, yT22, zT22) of the occurrence cause T22 of the feature pixel. That is, the intersection of the surface of the beam filter 118f1 and the line segment L300 is calculated as the position of the characteristic pixel generation cause T22. As described above, the discrimination function 230 includes the position coordinates of the surface of the beam filter 118, the irradiation position coordinates of the irradiation device 112 (xa1, ya1, za1), and the line segment connecting the coordinates of the feature pixels (xa3, ya3, za3). Based on the combination, it is possible to determine the position coordinates of the foreign matter.

The coordinate conversion function 231 will be described with reference to FIGS. 2 and 3 with reference to FIG. The coordinate conversion function 231 converts the three-dimensional position coordinates of the foreign object into the two-dimensional position coordinates on the XY plane. Here, the origin of the two-dimensional position coordinates is, for example, the center position of the X-ray tube 114 when the rotation of the arm 106 is 0 degrees. That is, the two-dimensional position coordinates at the center position of the X-ray tube 114 are (0, 0). Further, let the three-dimensional coordinates of the center position of the X-ray tube 114 when the rotation angle of the arm 106 is 0 degrees be (Xc1, Yc1, Zc1), for example. As a result, the coordinate conversion function 231 changes the three-dimensional position coordinates (X, Y, Z) of the foreign matter on the compression plate 126, the photographing table 124, and the X-ray detector 132 to the two-dimensional position coordinates ((X-Xc1). ), (Y-Yc1)).

In the case of the beam filter 118, the rotation of the arm 106 changes the three-dimensional position coordinates of the foreign matter on the beam filter 118. Therefore, in the case of the beam filter 118, the information on the rotation angle of the arm 106 is also used to convert the coordinates into two-dimensional position coordinates when the rotation angle of the arm 106 is 0 degrees.

More specifically, the coordinate conversion function 231 uses information on the angle of the arm 106 and the distance from the rotation center 108 to the beam filter 118, for example, to obtain three-dimensional position coordinates (xT22, yT22, zT22) of the arm 106. It is converted into two-dimensional position coordinates (xF22, yF22) when the rotation angle is 0 degrees. Also in this case, the origin of the two-dimensional position coordinates is set to the center position of the X-ray tube 114 when the rotation of the arm 106 is 0 degrees, for example. In this way, by converting the three-dimensional position coordinates of the foreign matter on the beam filter 118, the compression plate 126, the photographing table 124, and the X-ray detector 132 into the two-dimensional position coordinates, the coordinates of the foreign matter will be described later. Is shown on the map (for example, FIGS. 17 and 19), the operator can easily understand the position of the foreign matter.

Further, the coordinate conversion function 231 converts the two-dimensional position coordinates into the three-dimensional position coordinates based on the angle of the arm 106. For example, the coordinate conversion unit 231 converts two-dimensional coordinates into three-dimensional position coordinates based on the angle of the arm 106 and the distance from the rotation center 108 to the beam filter 118. Here, the distance from the rotation center 108 to the beam filter 118 is a fixed value, and the angle of the arm 106 can also be acquired. This makes it possible to present the position coordinates of the foreign matter on the beam filter 118, for example, on a map in which the angle of the arm 106 is other than 0 degrees.

Next, an example of irradiation conditions will be described with reference to FIG. 7. FIG. 7 is a diagram showing an example in which the beam filters 118f1, f2, and f3 are changed and the irradiation positions A, B, and C of the irradiation device 112 are changed. Here, the imaging control function 210 of the control circuit 204 sets the changes of the beam filters 118f1, f2, and f3 as the irradiation conditions, and sets a plurality of irradiation positions A, B, and C as the irradiation conditions. Under these irradiation conditions, X-rays are irradiated from three irradiation positions A, B, and C for each of the beam filters 118f1, f2, and f3. For example, the angles (FIG. 2) of the arm 106 corresponding to the irradiation positions A, B, and C of the irradiation device 112 are −θ, 0, and θ.

The above is a description of the configuration of the X-ray image diagnostic apparatus 1 according to the first embodiment, but a series of flow of imaging control in the X-ray image diagnostic apparatus 1 according to the first embodiment will be described below.

FIG. 8 is a diagram showing a flowchart showing a series of flow of imaging control in the inspection mode of the X-ray image diagnostic apparatus 1. Here, as shown in FIG. 7, a case where X-ray irradiation is performed from a plurality of irradiation positions A, B, and C for each of the plurality of beam filters 118f1, f2, and f3 will be described.

Step S100 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S100, the imaging control function 210 selects the beam filter 118f1 to be used for imaging based on the irradiation conditions.

Step S102 is a step corresponding to the change control function 214. This is a step in which the change control function 214 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the change control function 214 from the first storage circuit 202. In step S102, the change control function 214 controls the change motor 120 so as to change to the selected beam filter 118f1 according to the control of the imaging control function 210.

Step S104 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S104, the imaging control function 210 selects the first irradiation position A of the irradiation device 112 based on the irradiation conditions.

Step S106 is a step corresponding to the rotation control function 212. This is a step in which the rotation control function 212 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the rotation control function 212 from the first storage circuit 202. In step S106, the rotation control function 212 controls the rotation motor 122 to rotate the arm 106 until the irradiation device 112 installed on the arm 106 moves to the selected position A according to the control of the photographing control function 210. conduct.

Step S108 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S108, the imaging control function 210 controls the high voltage generator 600 to supply the tube voltage and the filament current, and the X-ray detector 132 to accumulate electric charges. Subsequently, the imaging control function 210 stops the supply of the tube voltage and the filament current to the high voltage generator 600, and controls the image generation circuit 134 to generate an X-ray image.

Step S110 is a step corresponding to the acquisition function 226. This is a step in which the acquisition function 226 is realized by the processing circuit 208 calling and executing a predetermined program corresponding to the acquisition function 226 from the first storage circuit 202. In step S110, the acquisition function 226 acquires the beam filter 118f1, the rotation angle −θ of the arm 106, and the position of the compression plate 126 as the type of the beam filter 118 as system information, and together with the X-ray image generated in step S108. In association with this, it is stored in the first storage circuit 202 together with the X-ray image.

Step S112 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S112, it is determined whether or not the imaging control function 210 has performed irradiation at all the irradiation positions A, B, and C based on the irradiation conditions. If the imaging at all the irradiation positions A, B, and C has not been completed (step S112: NO), the process returns to the process of step S104 described above, and the next irradiation position is selected. On the other hand, when the imaging at all the irradiation positions A, B, and C is completed (step S112: YES), the process proceeds to step S114.

Step S114 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S114, it is determined whether or not the imaging control function 210 has performed irradiation with all the beam filters 118f1, f2, and f3 based on the irradiation conditions. When all the beam filters 118f1, f2, and f3 have not been photographed (step S114: NO), the process returns to the process of step S100 described above, and the next beam filter is selected. On the other hand, when all the beam filters 118f1, f2, and f3 have been photographed (step S114: YES), the process proceeds to step S116.

Step S116 is a step corresponding to the image processing function 224. This is a step in which the image processing function 224 is realized by the processing circuit 208 calling and executing a predetermined program corresponding to the image processing function 224 from the first storage circuit 202. In step S116, a predetermined preprocessing is performed on all the X-ray images captured by the image processing function 224.

Step S118 is a step corresponding to the feature pixel detection function 228. This is a step in which the feature pixel detection function 228 is realized by the processing circuit 208 calling and executing a predetermined program corresponding to the feature pixel detection function 228 from the first storage circuit 202. In step S118, feature pixels are detected from all the X-ray images preprocessed in step S116. Then, the feature pixel detection function 228 stores the detected position information of the feature pixels in association with the system information stored in the first storage circuit 202, and ends a series of processes.

In this way, according to the control of the imaging control function 210, X-rays are irradiated from all the irradiation positions set in the irradiation conditions for each beam filter 118 set in the irradiation conditions. Subsequently, an X-ray image based on the irradiated X-ray is generated. Then, the feature pixels are detected from all the preprocessed X-ray images, and the positions of the feature pixels and the system information are stored in association with each other. As a result, the position information of the feature pixels, the X-ray image having the feature pixels, and the system information at the time of taking the X-ray image are associated with each other and stored in the first storage circuit 202.

Next, an example of the flow of processing for determining whether or not the beam filters 118f1, f2, and f3 have foreign matter or scratches will be described with reference to FIG. FIG. 9 is a diagram showing a flowchart illustrating an example of an algorithm of the determination function 230 for determining whether or not the beam filters 118f1, f2, and f3 have a cause of occurrence of characteristic pixels.

Here, an example of determining whether or not the beam filter 118 has a cause of occurrence of the feature pixels will be described using the information about the feature pixels detected in FIG. The processing circuit 208 calls and executes a predetermined program corresponding to the discrimination function 230 from the first storage circuit 202, and executes each step of the flowchart of FIG. 9 to realize the discrimination function 230.

In step S200, the discrimination function 230 selects an arbitrary irradiation position from the irradiation positions A, B, and C irradiated with X-rays according to the irradiation conditions. Here, the first irradiation position A is selected.

In step S202, the discrimination function 230 obtains all the X-ray images captured at the selected irradiation position A, the system information associated with the X-ray image, and the position information of the feature pixels associated with the X-ray image. Obtained from the first storage circuit 202. In step S204, the discrimination function 230 selects all the X-ray images captured at the selected irradiation position A.

In step S206, the X-ray image selected by the discrimination function 230 is binarized. Specifically, the discrimination function 230 allocates, for example, a constant 10.0 to the pixels corresponding to the positions of the feature pixels in the X-ray image to which the feature pixels are associated. On the other hand, 0.0 is allocated to pixels that are not feature pixels, for example. Further, 0.0 is assigned to all pixels for the X-ray image to which the feature pixels are not associated. As a result, the selected all X-ray images are converted into a binarized image in which 10.0 is assigned to the feature pixels and 0.0 is assigned to the other pixels. That is, 10.0 is allocated to the pixels below the predetermined threshold value used when selecting the feature pixels, and 0.0 is allocated to the other pixels.

In step S208, the discrimination function 230 compares the values of pixels having the same coordinates through all the binarized images. In this case, this comparison is made with respect to the coordinates of all the pixels constituting the image. After performing this comparison with respect to the coordinates of all the pixels, if even one of the pixel values of the same coordinates of the image corresponding to the different beam filters taken at the same irradiation position has a different value (step S208: YES). ), The coordinates are determined to be the coordinates of the feature pixels based on the foreign matter on the beam filter 118, and the process proceeds to step S210.

In step S210, the discrimination function 230 calculates the intersection of the line segment connecting the position coordinates of the irradiation device 112 and the coordinates of the feature pixels and the position coordinates on the surface of the beam filter 118 as the position coordinates of the foreign matter. In this case, the discrimination function 230 acquires the position coordinates on the surface of the beam filter 118 from the first storage circuit 202. Subsequently, the discrimination function 230 acquires the three-dimensional position coordinates of the foreign matter. Further, the coordinate conversion function 231 converts the three-dimensional position coordinates of the foreign object into the two-dimensional position coordinates. Then, the discrimination function 230 stores in the foreign matter table 218 the two-dimensional position coordinates of the foreign matter, the type of the beam filter 118 in which the foreign matter is present, and the date and time when the X-ray image including the feature pixels was taken, and a series of series. End the process.

On the other hand, in step S208, even if the comparison process is performed at all coordinates, if there is no different value among the pixel values of the same coordinates (step S208: NO), the discrimination function 230 is characterized by the beam filter 118. It is determined that there is no cause for pixel generation, the process of step S210 is skipped, and a series of processes is completed.

In this way, it is determined whether or not there is a change in the generation of feature pixels between the X-ray images generated in response to the change in the beam filter 118. When the generation of the feature pixels changes, it is determined that the beam filter 118 has the cause of the feature pixels. On the other hand, when there is no change in the generation of the feature pixels, it is determined that the beam filter 118 does not have the cause of the generation of the feature pixels.

Next, a process for determining whether or not there is a cause of occurrence of characteristic pixels in the X-ray irradiation path will be described with reference to FIG. FIG. 10 is a diagram showing a flowchart illustrating an example of an algorithm of the determination function 230 for determining whether or not there is a cause of occurrence of characteristic pixels in the X-ray irradiation path. Here, the discrimination process is performed using the information regarding the feature pixels detected in FIG. 8 and the information of the beam filter 118 in which the foreign matter and the like discriminated in FIG. 9 are present. The processing circuit 208 calls and executes a predetermined program corresponding to the discrimination function 230 from the first storage circuit 202, thereby executing each step of the flowchart of FIG. 10 to realize the discrimination function 230.

In step S300, the discrimination function 230 acquires the X-ray image, the position information of the feature pixels, and the system information from the first storage circuit 202, excluding the information about the X-ray image captured by the beam filter 118 containing foreign matter. In step S302, the discrimination function 230 extracts the positions of the feature pixels among the X-ray images generated by the plurality of irradiation positions.

In step S304, the discrimination function 230 determines whether or not the positions of the extracted feature pixels change between the X-ray images taken at different irradiation positions. When the position of the feature pixel does not change (step S304: No), it is determined that the X-ray detector 132 has the cause of the feature pixel generation, and the process proceeds to step S306.
Since the range in which the position of the feature pixel moves between different images is determined according to the moving range of the irradiation position, the change in the position of the feature pixel in each image within the moving range may be detected. This makes it possible to identify the feature pixels corresponding to the same foreign matter and detect the change in position even when there are a plurality of foreign matters in one image.

In step S306, the discrimination function 230 stores the X-ray detector 132 as the coordinates of the extracted feature pixels, the date and time when the feature pixels were imaged, and the unit name in the defect point table 222 of the second storage circuit 206.

On the other hand, in step S304, when the position of the feature pixel changes between the X-ray images (step S304: Yes), it is determined that the cause of the feature pixel is generated in the X-ray irradiation path. Then, the process proceeds to step S308.

In step S308, the discrimination function 230 acquires the height in the Z-axis direction in which the feature pixel is generated, which corresponds to the movement amount of the feature pixel. The height is determined by the method described with reference to FIGS. 4 and 6. In step S310, the discrimination function 230 determines that the cause of the occurrence of the feature pixel exists in the unit corresponding to the acquired height. That is, it is determined in which unit the cause of the feature pixel is present. As a method of specifying the unit, instead of using the height, the correspondence between the movement amount and the corresponding unit may be stored, and the unit may be determined from the movement amount based on the correspondence.

When the process of step S306 is completed and the process of step S310 is completed, in step S312, the discrimination function 230 causes the display 400 to display the unit having the cause of the abnormal pixel. Then, a series of processes is completed. The display is displayed with the name of the unit causing the occurrence or a diagram that can identify the unit causing the occurrence on the device.

In this way, when the positions of the feature pixels change between the X-ray images generated by the plurality of irradiation positions, it is determined that the cause of the feature pixels is generated in the X-ray irradiation path. On the other hand, when the positions of the feature pixels do not change between the X-ray images generated by the plurality of irradiation positions, the X-ray detector 132 determines that the cause of the feature pixels is generated. Further, when it is determined that there is a cause of occurrence of the feature pixel in the X-ray irradiation path, the unit in which the cause of occurrence exists is determined based on the amount of movement in which the cause of occurrence exists.

As described above, in the present embodiment, the discrimination function 230 determines the cause of the occurrence of the feature pixels based on the change of the feature pixels between the X-ray images generated by the plurality of irradiation conditions. This makes it possible to determine the location of the foreign matter or the like that is the cause of the feature pixels, and it is possible to process the foreign matter or the like more efficiently.

Further, when the discrimination function 230 changes the position of the feature pixel between the X-ray images generated by the plurality of irradiation positions of the irradiation device 112, it is said that there is a cause of the feature pixel generation in the X-ray irradiation path. It was decided to discriminate. As a result, it is determined that the place where the foreign matter is present is in the X-ray irradiation path, and it is possible to more efficiently process the foreign matter or the like in the X-ray irradiation path.

(Second Embodiment)
In the first embodiment described above, the irradiation positions A, B, and C are changed for each of the beam filters 118f1, f2, and f3, but in the second embodiment, the beam filters 118f1 for each of the irradiation positions A, B, and C, I am trying to change f2 and f3. Hereinafter, parts different from the above-described first embodiment will be described. Since the overall configuration of the X-ray diagnostic imaging apparatus 1 is the same as that of the first embodiment, the description thereof will be omitted.

Next, an example of irradiation conditions will be described with reference to FIG. FIG. 11 is a diagram showing an example in which the beam filters 118f1, f2, and f3 are changed for each irradiation position A, B, and C of the irradiation device 112.

Here, the imaging control function 210 of the control circuit 204 sets a plurality of irradiation positions A, B, and C as irradiation conditions, and changes the beam filters 118f1, f2, and f3 as irradiation conditions. Under these irradiation conditions, X-ray irradiation is performed while changing the beam filters 118f1, f2, and f3 for each of the three irradiation positions A, B, and C.

Based on FIG. 12, a series of flow of imaging control in the X-ray image diagnostic apparatus 1 according to the second embodiment will be described. FIG. 12 is a diagram showing a flowchart showing a series of flow of shooting control according to the second embodiment. Here, as shown in FIG. 11, a case where X-ray irradiation is performed while changing a plurality of beam fills f1, f2, and f3 for each of the plurality of irradiation positions A, B, and C will be described. Further, here, the algorithm of the determination function 230 for determining whether or not the beam filters 118f1, f2, and f3 described with reference to FIG. 9 have the cause of the occurrence of the feature pixel is used.

As shown in FIG. 12, step S400 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S400, the imaging control function 210 selects the irradiation position A of the irradiation device 112 based on the irradiation conditions.

Step S402 is a step corresponding to the rotation control function 212. This is a step in which the rotation control function 212 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the rotation control function 212 from the first storage circuit 202. In step S402, the rotation control function 212 controls the rotation motor 122 to rotate the arm 106 until the irradiation device 112 installed on the arm 106 moves to the selected position A according to the control of the photographing control function 210. conduct.

Step S404 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S404, the imaging control function 210 selects the beam filter 118f1 to be used for imaging based on the irradiation conditions.

Step S406 is a step corresponding to the change control function 214. This is a step in which the change control function 214 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the change control function 214 from the first storage circuit 202. In step S406, the change control function 214 controls the change motor 120 so as to change to the selected beam filter 118f1 according to the control of the imaging control function 210.

Step S108 and step S110 perform the same processing as in FIG. That is, an X-ray image is generated, associated with system information, and stored in the first storage circuit 202.

Step S408 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S408, it is determined whether or not the imaging control function 210 has performed irradiation with all the beam filters 118f1, f2, and f3 based on the irradiation conditions. When all the beam filters 118 f1, f2, and f3 have not been photographed (step S408: NO), the process returns to the process of step S404 described above, and the next beam filter 118 is selected. On the other hand, when all the beam filters 118f1, f2, and f3 have been photographed (step S408: YES), the process proceeds to step S116.

Steps S116 to S118 perform the same processing as in FIG. That is, the image processing function 224 applies a predetermined preprocessing to all the X-ray images captured at the same irradiation position, and the feature pixel detection function 228 detects the feature pixels from all the preprocessed X-ray images. ..

In step S410, the processing circuit 208 calls and executes a predetermined program corresponding to the discrimination function 230 from the first storage circuit 202, thereby executing each step of the flowchart of FIG. 9 to realize the discrimination function 230. .. Here, when the beam filter 118 in which the foreign matter is present is determined, the beam filter 118 in which the foreign matter is present is excluded from the selection of the beam filter 118 in the above-mentioned Tep S404. That is, the beam filter 118 in which foreign matter is present is not used for X-ray imaging in the inspection mode.

Step S412 is a step corresponding to the shooting control function 210. This is a step in which the photographing control function 210 is realized by the control circuit 204 calling and executing a predetermined program corresponding to the photographing control function 210 from the first storage circuit 202. In step S412, it is determined whether or not the imaging control function 210 has performed irradiation at all the irradiation positions A, B, and C based on the irradiation conditions. If the imaging at all the irradiation positions A, B, and C has not been completed (step S412: NO), the process returns to the process of step S400 described above, and the next irradiation position is selected. On the other hand, when the imaging at all the irradiation positions A, B, and C is completed (step S412: YES), the series of processes is completed.

In this way, according to the control of the imaging control function 210, X-ray irradiation is performed while changing the beam filter 118 set in the irradiation conditions for all the irradiation positions set in the irradiation conditions. Subsequently, an X-ray image based on the irradiated X-ray is generated. Then, the feature pixels are detected from all the preprocessed X-ray images, and the positions of the feature pixels and the system information are stored in association with each other. As a result, the position information of the feature pixels, the X-ray image having the feature pixels, and the system information at the time of taking the X-ray image are associated and stored. Further, when the imaging at the irradiation position A is completed, it is determined whether or not the beam filters 118f1, f2, and f3 have the cause of the generation of the feature pixels. When any one of the beam filters 118f1, f2, and f3 has a cause of the characteristic pixel generation, the beam filter 118 is not used in the subsequent shooting in the inspection mode, so that the imaging in the inspection mode can be made more efficient.

As described above, in the present embodiment, the beam filters 118f1, f2, and f3 are changed for each irradiation position A, B, and C. As a result, it is possible to determine the cause of the occurrence of the feature pixels in the beam filters 118f1, f2, and f3 at the timing when the imaging at the irradiation position A is completed, and the determination process can be performed more efficiently.

(Third Embodiment)
In the first embodiment described above, the discrimination function 230 displays the unit having the cause of the abnormal pixel on the display 400, but in the present embodiment, the foreign matter map, the scratch map, and the foreign matter map generated by the generation function 232 are displayed. A mixed map of foreign matter and scratches and a defect point map are displayed on the display 400. Hereinafter, parts different from the above-described first embodiment will be described.

FIG. 13 is a block diagram showing a configuration of the information processing apparatus 200 according to the third embodiment. It is different from the information processing apparatus 200 according to the first embodiment by further providing the generation function 232. Further, the discrimination function 230 is different from the information processing device 200 according to the first embodiment because it further has a function of discriminating between foreign matter and scratches based on the foreign matter table 218.

The generation function 232 generates a foreign matter map, a scratch map, a mixed foreign matter and scratch map, and a defect point map. That is, the generation function 232 generates a foreign matter map showing which position in the X-ray image diagnostic apparatus 1 the foreign matter exists based on the position coordinates of the foreign matter stored in the foreign matter table 218 of the second storage circuit 206. do. Similarly, the generation function 232 creates a scratch map indicating which position in the X-ray image diagnostic apparatus 1 the scratch exists based on the position coordinates of the scratch stored in the scratch table 220 of the second storage circuit 206. Generate. Further, the generation function 232 is based on the position coordinates of the scratches stored in the foreign matter table 218 and the scratch table 220 of the second storage circuit 206, and at which position in the X-ray image diagnostic apparatus 1 the foreign matter and the scratch are present. Generate a mixed map of foreign matter and scratches showing. Furthermore, the generation function 232 determines at which position of the line detector the image sensor corresponding to the defect point exists based on the position coordinates of the defect point stored in the defect point table 222 of the second storage circuit 206. Generate the defect map shown. More specifically, the generation function 232 is connected to the control circuit 204 and the display 400, and under the control of the imaging control function 210 of the control circuit 204, these foreign matter maps, scratch maps, and defect point maps are displayed on the display 400. To display.

Next, an example of scratch discrimination performed by the discrimination function 230 will be described with reference to FIG. FIG. 14 is a diagram showing an example of the foreign matter table 218 and the scratch table 220. The foreign matter table 1 of FIG. 14 is a diagram showing a table in which the discrimination function 230 stores information regarding foreign matter. Here, since the foreign matter or scratches discriminated by the discrimination function 230 have not yet been distinguished from the foreign matter and the scratches, they are uniformly and comprehensively stored as foreign matter. Further, as described above, as the position coordinates, the two-dimensional position coordinates of the foreign matter converted by the coordinate conversion function 231 are stored.
The foreign matter number is a number assigned to each stored foreign matter. Here, NO. Numbers are numbered from 1 to 4. Further, the date and time of occurrence indicates the date and time when the feature pixel was generated. The number of shots indicates the number of shots after the foreign matter is stored. The unit name indicates the unit of the mammography apparatus 100 in which the cause of the characteristic pixel is present.

By the way, even if an X-ray image is taken by changing the irradiation position, it is difficult to determine whether it is a foreign substance or a scratch. On the other hand, if there is a scratch, it is necessary to repair or replace the member. Further, in the normal mammography apparatus 100, cleaning is performed every time an image is taken. Therefore, if it is a foreign substance, there is a high possibility that it will disappear after a predetermined number of photographs have been taken. On the other hand, if it is a scratch, it will not disappear by cleaning.

Therefore, in the discrimination function 230 according to the present embodiment, if the foreign matter is stored in the foreign matter table 218 and then the foreign matter is present at the same coordinates even if the X-ray image is taken a predetermined number of times, the foreign matter is scratched. To determine.

In the scratch table shown in FIG. 14, the information stored in the foreign matter table 218 is stored in the scratch table 220 after the discrimination function 230 discriminates the foreign matter as scratches. As a foreign matter number, NO. 1 is memorized. In this way, the NO. Stored in the foreign matter table 218. The foreign matter of No. 1 is stored in the scratch table 220 again after being determined as a scratch. The other description elements are the same as those of the foreign matter table 218. The foreign matter table 2 shown in FIG. 14 has a NO. The foreign matter table 1 after removing the foreign matter of 1 is shown. Each description element is the same as that of the foreign matter table 1.

FIG. 15 is a diagram showing an example of a defect table. The defect table shown in FIG. 15 is a diagram showing a table in which the position coordinates of the defective pixels and the date and time of occurrence are stored. That is, the discriminating function 230 discriminates the cause of the occurrence of the feature pixel from the X-ray detector 132, and stores the position coordinates of the defective pixel and the date and time of occurrence. Similar to the foreign matter table 218 shown in FIG. 14, the foreign matter number is a number assigned to each stored foreign matter. Here, NO. Numbers are numbered from 5 to 8. Further, the position coordinates indicate the position coordinates of the feature pixels. The date and time of occurrence indicates the date and time when the X-ray image including the feature pixels was captured. The unit name indicates the unit of the mammography apparatus 100 in which the cause of the characteristic pixel is present.

Next, an example of the foreign matter map, the scratch map, the foreign matter and scratch mixed map, and the defect point map generated by the generation function 232 will be described with reference to FIGS. 16 to 20. As described above, the foreign matter map, the scratch map, the foreign matter and scratch mixed map, and the defect point map are displayed on the display 400.

FIG. 16 is a diagram showing a foreign matter map generated by the generation function 232. 16 (a) is a diagram showing the position of foreign matter on the beam filter 118, FIG. 16 (b) is a diagram showing the position of foreign matter on the compression plate 126, and FIG. 16 (c) is a diagram showing the position of foreign matter on the compression plate 126. It is a figure which shows the position of the foreign matter on a plate 126. In this way, the position of the foreign matter is illustrated for each unit. Since the position coordinates of the foreign matter are reflected, the inspector can easily confirm the position of the foreign matter.

FIG. 17 is a diagram showing a scratch map generated by the generation function 232. In this figure, the position coordinates of the scratches are also shown. FIG. 17A is a diagram showing the position of scratches on the beam filter 118, FIG. 17B is a diagram showing the position of scratches on the compression plate 126, and FIG. 17C is a diagram showing compression. It is a figure which shows the position of the scratch on a plate 126. In this way, the position of the scratch is illustrated for each unit. Since the position coordinates of the scratches are reflected on the drawing, the inspector can easily confirm the position of the foreign matter. Moreover, since the position coordinates of the scratches are displayed, it is possible to accurately grasp the positions of the scratches. The angle of the arm 106 here is 0 degrees. Therefore, the two-dimensional coordinates stored in the scratch table 220 are used for the positions of the scratches on the beam filter 118.

FIG. 18 is a diagram showing a mixed map of foreign matter and scratches generated by the generation function 232. FIG. 18A is a diagram showing the positions of foreign matter and scratches on the beam filter 118, and FIG. 18B is a diagram showing the positions of foreign matter and scratches on the compression plate 126, and FIG. 18C. ) Is a diagram showing the positions of foreign matter and scratches on the compression plate 126. In this way, the positions of foreign matter and scratches are illustrated for each unit. Since the position coordinates of the foreign matter and the scratch are reflected on the drawing, the inspector can easily confirm the position of the foreign matter and the scratch. Moreover, since both foreign matter and scratches are displayed, it is possible to easily confirm the positions of both.

FIG. 19 is a mixed map of foreign matter and scratches generated by the generation function 232, and is a diagram reflecting the height in the Z-axis direction. Since the positions of the foreign matter and the dust are shown in the image reflecting the height, the positional relationship of the foreign matter and the dust in the breast device can be easily grasped. Further, since the position coordinates of the foreign matter and the scratch are displayed, it is possible to accurately grasp the position of the foreign matter and the scratch. The angle of the arm 106 here is 0 degrees. Therefore, the two-dimensional coordinates stored in the foreign matter table 218 are used for the position of the foreign matter on the beam filter 118, and the two-dimensional coordinates stored in the scratch table 220 are used for the position of the scratch on the beam filter 118. ing.

FIG. 20 is a diagram of a foreign matter map showing the positions of foreign matter on a schematic diagram of the actual machine. In the figure of this foreign matter map, the position of the foreign matter is highlighted. Since the position of the foreign matter is shown in the schematic diagram of the actual machine, it is possible to make a comparison with the actual machine more easily. Moreover, since the position of the foreign matter is highlighted, the position of the foreign matter can be easily grasped.

FIG. 21 is a diagram showing a defect point map generated by the generation function 232. In this way, the positions of the defective pixels are shown on the detection surface of the X-ray detector 132. Since the position coordinates of the defective pixels are reflected on the drawing, the inspector can easily confirm the positions of the defective pixels.

Next, a process for determining whether or not the cause of occurrence of the feature pixel is a scratch will be described with reference to FIGS. 22 and 23. 22 and 23 are diagrams showing a flowchart for explaining the algorithm of the determination function 230 for determining whether or not the cause of occurrence of the feature pixel is a scratch. The processing circuit 208 calls and executes a predetermined program corresponding to the discrimination function 230 from the first storage circuit 202, thereby executing each step of the flow charts of FIGS. 22 and 23 to realize the discrimination function 230.

The processes from step S300 to step S310 are the same as the processes described with reference to FIG. 10 of the first embodiment. That is, when the feature pixel does not move, the coordinates of the feature pixel are stored in the defect point table 222. On the other hand, when the feature pixels move, it is determined which unit of the photographing table 124 and the compression plate 126 has a foreign substance that is the cause of the feature pixels.

In step S500, the discrimination function 230 classifies the feature pixels into units. In step S502, the discrimination function 230 calculates the position coordinates of the cause of occurrence of the feature pixels from the feature pixels classified for each unit. More specifically, the position coordinates of the foreign matter are calculated based on the combination of the plurality of irradiation positions and the positions of the corresponding feature pixels.

In step S504, the discrimination function 230 stores the position coordinates of the occurrence cause of the feature pixels, the occurrence time of the feature pixels, and the unit in which the occurrence cause of the feature pixels exists in the foreign matter table 218 of the second storage circuit 206. Further, the discrimination function 230 updates the number of shots taken from the generation time of the feature pixels stored in the foreign matter table 218 every time the shooting is performed.

When the process of step S306 is completed and the process of step S504 is completed, in step S506, whether the number of shots of the foreign matter already stored in the foreign matter table 218 by the discrimination function 230 exceeds a predetermined number of times. Determine if not. When the number exceeds the predetermined number (step S506: Yes), it is determined that the foreign matter is a scratch.

In step S508, the discrimination function 230 stores the foreign matter determined to be scratches in the scratch table 220. Then, the information of the foreign matter determined to be a scratch is deleted from the foreign matter table 218, and a series of processing is completed. On the other hand, if the number of sheets does not exceed the predetermined number (step S506: Yes), step S508 is skipped and a series of processes is completed.

Next, an example of map display processing will be described with reference to FIG. 24. FIG. 24 is a diagram showing a flowchart illustrating the algorithm of the generation function 232 in the processing circuit 208. The processing circuit 208 calls and executes a predetermined program corresponding to the generation function 232 from the first storage circuit 202, thereby executing each step of the flowchart of FIG. 24 to realize the discrimination function 230.

In step S600, the generation function 232 acquires position coordinates and unit information that cause the generation of feature pixels from the foreign matter table 218, the scratch table 220, and the defect point table 222 stored in the second storage circuit 206. In step S602, the generation function 232 generates a foreign matter map, a scratch map, a foreign matter and scratch mixed map, and a defect point map based on the acquired position coordinates and unit information.

In step S604, the generated foreign matter map, scratch map, foreign matter and scratch mixed map, and foreign matter, scratch, and defective pixel position in the defect point map are highlighted. In this case, foreign matter, scratches, defective pixel positions on the map are enlarged, colored, surrounded, marked, and the like.

In step S606, each highlighted map is displayed on the display 400, and the process ends. A map that has not been highlighted may be displayed on the display 400.

As described above, in the present embodiment, the foreign matter map, the scratch map, the mixed foreign matter and scratch map, and the defect point map generated by the generation function 232 are displayed on the display 400. As a result, the positions of foreign matter, scratches, and defective pixels can be grasped more accurately.

Further, the discrimination function 230 according to the present embodiment determines that the foreign matter is scratched when the foreign matter is present at the same coordinates even if the X-ray image is taken a predetermined number of times after the foreign matter is stored in the foreign matter table 218. It was decided to discriminate. As a result, foreign matter and scratches can be discriminated, and cleaning and repair can be performed more efficiently.

The irradiation device 112 in the first embodiment is an example of an irradiation unit in the claims, and the image generation circuit 134 is an example of an image generation unit in the claims. The feature pixel detection function 228 in the first embodiment is an example of the feature pixel detection unit in the claims. The discrimination function 230 in the first embodiment is an example of a discrimination unit within the scope of claims. Further, the discrimination function 230 in the third embodiment is another example of the discrimination unit within the scope of claims. The generation function 232 in the third embodiment is an example of a generation unit within the scope of claims. The second storage circuit 206 in the first embodiment is an example of a storage unit within the scope of claims. The display 400 in the first embodiment is an example of a display unit within the scope of claims. Further, the unit in the first embodiment is an example of the device in the claims, and the unit in the third embodiment is another example of the device in the claims.

The term "processor" used in the above description refers to, for example, a CPU (central processing unit), a GPU (Graphics Processing Unit), or an application specific integrated circuit (ASIC), a programmable logic device (for example, an ASIC), or a programmable logic device (ASIC). Simple programmable logic device (Single Programmable Logical Device: SPLD), composite programmable logic device (Complex Programmable Logical Device: CPLD), and field programmable gate array (Field Programmable Gate Array: FPGA). The processor realizes the function by reading and executing the program stored in the first storage circuit 202. Instead of storing the program in the first storage circuit 202, the program may be directly incorporated in the circuit of the processor. In this case, the processor realizes the function by reading and executing the program embedded in the circuit. It should be noted that each processor of the present embodiment is not limited to the case where each processor is configured as a single circuit, and a plurality of independent circuits may be combined to form one processor to realize its function. good. Further, the plurality of components in FIGS. 1, 3 and 13 may be integrated into one processor to realize the function.

Although some embodiments have been described above, these embodiments are presented only as examples and are not intended to limit the scope of the invention. The novel devices and methods described herein can be implemented in a variety of other forms. In addition, various omissions, substitutions, and changes can be made to the forms of the apparatus and method described in the present specification without departing from the gist of the invention. The appended claims and their equivalent scope are intended to include such forms and variations contained within the scope and gist of the invention.

1: X-ray image diagnostic device, 118: beam filter, 124: imaging table, 126: compression plate, 132: X-ray detector, 134: image generation circuit, 206: recording circuit, 228: feature pixel detection function, 230: Discrimination function, 232: Generation function, 400: Display

Claims (14)

An irradiation part that can irradiate X-rays under multiple irradiation conditions,
An X-ray detector that detects the X-rays emitted from the irradiation unit, and
An image generator that generates an X-ray image based on the X-rays detected by the X-ray detector, and
A feature pixel detection unit that detects feature pixels whose pixel values in the X-ray image are different from other pixel values, and
A discriminating unit that determines the cause of occurrence of the feature pixels based on changes in the feature pixels between the X-ray images generated by the plurality of irradiation conditions.
With
In the irradiation unit, the beam filter can be changed as the irradiation condition.
The discriminating unit determines that the beam filter has a cause of generation of the feature pixels when the generation of the feature pixels changes between the X-ray images generated in response to the change of the beam filter. , X-ray diagnostic imaging equipment. In the irradiation unit, a plurality of irradiation positions can be set as the irradiation conditions.
When the position of the feature pixel changes between the X-ray images generated by the plurality of irradiation positions, the discriminating unit determines that the cause of the feature pixel is generated in the X-ray irradiation path. The X-ray image diagnostic apparatus according to claim 1. In the irradiation unit, a plurality of irradiation positions can be set as the irradiation conditions.
The determination unit determines that the X-ray detector has a cause of generation of the feature pixels when the positions of the feature pixels do not change between the X-ray images generated by the plurality of irradiation positions. Item 1. The X-ray image diagnostic apparatus according to item 1. As the movement amount of the feature pixel becomes larger than the movement amount of the irradiation position, the discriminating unit moves the feature pixel to a position further away from the X-ray detector in the X-ray irradiation path. The X-ray image diagnostic apparatus according to claim 2, wherein it is determined that there is a cause of occurrence. A plurality of types of devices are further provided in the X-ray irradiation path.
The X-ray image according to claim 4, wherein the discriminating unit determines which of the plurality of devices is the cause of the occurrence of the feature pixels based on the amount of movement of the feature pixels between the X-ray images. Diagnostic device. A compression plate used to compress the subject, which can be moved up and down, and
An imaging table arranged between the compression plate and the detection surface of the X-ray detector,
Further prepare
Based on the amount of movement of the feature pixels between the X-ray images, the discriminating unit causes the feature pixels to be generated by the compression plate, the photographing table, the photographing table, and the detection surface of the X-ray detector. The X-ray image diagnostic apparatus according to claim 4, wherein the X-ray detector determines which of the two and the X-ray detector is present. The discriminating unit obtains the position coordinates of the foreign matter based on the combination of the position of the irradiation unit and the position of the corresponding feature pixel.
The X-ray image diagnostic apparatus according to any one of claims 1 to 6, further comprising a storage unit for storing the position coordinates of the foreign substance. The discrimination unit determines that the foreign matter is a scratch when the foreign matter is stored in the storage unit and then exists at the same coordinates even if a predetermined number of the X-ray images are imaged.
The X-ray image diagnostic apparatus according to claim 7, wherein the foreign matter is stored in the storage unit as a scratch. The eighth aspect of claim 8, further comprising a generation unit that generates a foreign matter map indicating at which position in the X-ray image diagnostic apparatus the foreign matter exists based on the position coordinates of the foreign matter stored in the storage unit. X-ray diagnostic imaging equipment. The ninth aspect of the present invention, wherein the generation unit generates a scratch map indicating at which position in the X-ray image diagnostic apparatus the scratch exists based on the position coordinates of the scratch stored in the storage unit. X-ray diagnostic imaging system. When the position of the feature pixel does not move with respect to the position movement of the irradiation unit, the discriminating unit stores the position coordinates of the feature pixel in the storage unit.
The X-ray according to claim 10, wherein the generation unit generates a defect point map indicating at which position of the X-ray detector the defect pixel exists based on the position coordinates stored in the storage unit. Diagnostic imaging device. The X-ray diagnostic imaging apparatus according to claim 11, further comprising a display unit that displays at least one of the foreign matter map, the scratch map, and the defect point map. The process of irradiating X-rays from the irradiation part, which can irradiate X-rays under multiple irradiation conditions,
The process of detecting the X-ray with an X-ray detector and
A step of generating an X-ray image based on the X-ray detected by the X-ray detector, and
A step of detecting a feature pixel whose pixel value in the X-ray image is different from that of other pixel values, and
A step of determining the cause of occurrence of the feature pixels based on changes in the feature pixels between the X-ray images generated by the plurality of irradiation conditions, and a step of determining the cause of the feature pixels.
With
In the irradiation unit, the beam filter can be changed as the irradiation condition.
In the step of determining, when there is a change in the generation of the feature pixels between the X-ray images generated in response to the change of the beam filter, it is determined that the beam filter has the cause of the generation of the feature pixels. A method of controlling an X-ray image diagnostic apparatus. An irradiation part that can irradiate X-rays under multiple irradiation conditions,
An X-ray detector that detects the X-rays emitted from the irradiation unit, and
An image generator that generates an X-ray image based on the X-rays detected by the X-ray detector, and
A feature pixel detection unit that detects feature pixels whose pixel values in the X-ray image are different from other pixel values, and
Based on the change of the feature pixel between the X-ray images generated by the plurality of irradiation conditions, the position coordinates including the height direction in which at least one of the foreign matter and the scratch is generated are obtained, and the X-ray image diagnostic apparatus. Of the plurality of units constituting the above, a discriminating unit for displaying the unit corresponding to the position coordinates including the height direction on the display unit in an identifiable manner, and
X-ray diagnostic imaging apparatus.

Images