X-ray diagnosis apparatus, medical image processing device, and program

Abstract

To enable confirmation of the influence of body motion of a subject in an X-ray image.SOLUTION: An X-ray diagnosis apparatus according to an embodiment includes an X-ray source, an X-ray detector, and a medical image processing device. The X-ray source irradiates X-rays toward a subject with a variable irradiation angle. The X-ray detector is disposed at a position facing the X-ray source and detects X-rays that have passed through the subject and reached in a state where a positional relationship relative to the X-ray source is fixed. The medical image processing device acquires a plurality of temporally-consecutive X-ray images generated on the basis of the X-rays at different irradiation angles detected by the X-ray detector, and causes a display device to display a body motion index representing body motion of the subject between the capturing of the first X-ray image and the capturing of the second X-ray image on the basis of an internal image of the subject depicted in the first X-ray image and the second X-ray image which are temporally consecutive among the plurality of X-ray images.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The embodiments of the present invention relate to an X-ray diagnostic apparatus, a medical image processing apparatus, and a program. [Background technology]

[0002] Conventionally, in X-ray diagnostic devices that take X-ray images, there is a technology called multi-shot long-length, which takes multiple X-ray images and stitches them together to generate a long X-ray image. In this multi-shot long-length technology, for example, multiple X-ray images are taken by changing the irradiation direction of the X-ray beam while maintaining the X-ray focal point at a fixed position, i.e., in a fixed focal point state.

[0003] However, when a multi-shot long X-ray image (hereinafter referred to as a "long X-ray image") is captured using an X-ray diagnostic device, distortions may occur in the captured long X-ray image. One possible cause of this is movement of the subject (patient) during imaging. For example, when generating a long X-ray image using an X-ray diagnostic device, X-ray images with a predetermined angle of view are captured multiple times, and a predetermined time (e.g., 5 seconds) is required between capturing each X-ray image. During this time, the patient may not be able to maintain the same posture, resulting in bodily movement of the patient being imaged between captures of each X-ray image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-240656 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the embodiments disclosed in this specification and the drawings is to enable confirmation of the influence of the subject's body movement in an X-ray image. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problems. It is also possible to position, as other problems, the problems corresponding to the respective effects of each configuration shown in the embodiments described later.

Means for Solving the Problem

[0006] The X-ray diagnostic apparatus according to the embodiment includes an X-ray source, an X-ray detector, and a medical image processing apparatus. The X-ray source irradiates the subject with X-rays while variably changing the irradiation angle. The X-ray detector is disposed at a position facing the X-ray source, and detects the X-rays that have passed through the subject in a state where the positional relationship with the X-ray source is fixed. The medical image processing apparatus acquires a plurality of temporally continuous X-ray images generated based on the X-rays having different irradiation angles detected by the X-ray detector, and based on the internal images of the subject depicted in the first X-ray image and the second X-ray image that are temporally continuous among the plurality of X-ray images, causes a display device to display a body movement index representing the body movement of the subject during the imaging between the first X-ray image and the second X-ray image.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Best Mode for Carrying Out the Invention

[0008] Hereinafter, with reference to the drawings, an X-ray diagnostic apparatus, a medical image processing apparatus, and a program according to embodiments will be described. The X-ray diagnostic apparatus is a medical diagnostic apparatus that irradiates a subject (patient) with X-rays and generates a two-dimensional X-ray image that images the state of the patient's body by detecting the X-rays that have passed through the patient's body. An operator (such as a doctor or a technician) who performs X-ray diagnosis using the X-ray diagnostic apparatus can visually confirm whether there is a lesion or the like in the patient based on the generated X-ray image. In the following description, it is assumed that a plurality of X-ray images are taken by the X-ray diagnostic apparatus, and a multi-shot long X-ray image (hereinafter referred to as a "long X-ray image") is taken by connecting the respective X-ray images.

[0009] FIG. 1 is a diagram showing an example of the configuration and usage environment of an X-ray diagnostic apparatus according to an embodiment. The X-ray diagnostic apparatus 1 includes, for example, a table device 10, an X-ray source 20, an X-ray detector 30, a medical image processing apparatus 100, and a display device 200.

[0010] The table device 10 is a bed on which a subject (patient) P to be imaged is placed. The table device 10 includes, for example, a table 12 and a table elevator 14. The table elevator 14 moves the table 12 with the patient P placed thereon up and down. In the present embodiment, the longitudinal direction of the table 12 of the table device 10 is defined as the Y-axis direction, an axis that is orthogonal to the Y-axis direction and horizontal with respect to the floor surface of the room (imaging room) in which the X-ray diagnostic apparatus 1 is installed is defined as the X-axis direction, and a direction that is orthogonal to the Y-axis direction and perpendicular to the floor surface is defined as the Z-axis direction. Therefore, the table elevator 14 moves the table 12 with the patient P placed thereon in the Z-axis direction.

[0011] The X-ray source 20 irradiates the patient P with X-rays r for imaging the inside of the patient P. The X-ray source 20 can have its X-ray irradiation angle changed (the X-ray irradiation angle can be made variable) under the control from the irradiation control unit 120 provided in the medical image processing apparatus 100 described later. When taking a long X-ray image, the X-ray source 20 irradiates the patient P with each X-ray r while overlapping a part of the X-ray irradiation range. In FIG. 1, in order to take a long X-ray image, the X-ray source 20 is rotated in the Y-axis direction (in other words, the X-ray source 20 is swung like a pendulum), and the state in which each of the X-rays r-1, r-2, and r-3 is irradiated to the patient P is shown.

[0012] The X-ray detector 30 detects the X-rays r that are irradiated from the X-ray source 20, pass through the body of the patient P, and arrive. The X-ray detector 30 is disposed, for example, on the surface (so-called, the back surface side of the imaging table 12) opposite to the side on which the patient P is placed on the imaging table 12 of the imaging table device 10. That is, the X-ray detector 30 is disposed at a position facing the X-ray source 20 with the imaging table 12 interposed therebetween. The X-ray detector 30 is in a state where the positional relationship with respect to the distance from the X-ray source 20 is fixed. Thereby, the X-ray detector 30 detects the X-rays r that are irradiated from the X-ray source 20, pass through the body of the patient P, and arrive, in a state where the focal point is maintained at a fixed position (a state of focal point fixation). The state of focal point fixation is a state where the distance between the X-ray source 20 and the X-ray detector 30 is made constant. The X-ray detector 30 generates a two-dimensional X-ray image that images the state inside the body of the patient P according to the magnitude of the energy of the detected X-rays r. The X-ray detector 30 generates an X-ray image each time X-rays are irradiated from the X-ray source 20 toward the patient P. In the X-ray detector 30, for example, X-ray detectors are arranged in a two-dimensional array. The X-ray detector 30 generates a digital image obtained by imaging, in digital values, the magnitude of the energy of the X-rays r that have reached each detector, as an X-ray image. The X-ray detector 30 is, for example, a Flat Panel Detector (FPD). The X-ray detector 30 outputs the generated X-ray image to the medical image processing apparatus 100. In FIG. 1, each of the X-ray images (three X-ray images) generated by detecting each of the X-rays r-1, r-2, and r-3 irradiated by the X-ray source 20 is output to the medical image processing apparatus 100.

[0013] A method for outputting an X-ray image generated by the X-ray detector 30 to the medical image processing apparatus 100, in other words, a method for transmitting the X-ray image from the X-ray detector 30 to the medical image processing apparatus 100, may use a signal line between the X-ray detector 30 and the medical image processing apparatus 100, that is, a wired method, or may be a method using wireless communication between the X-ray detector 30 and the medical image processing apparatus 100. The X-ray detector 30 and the medical image processing apparatus 100 may be configured to be connected by, for example, a LAN (Local Area Network) or a WAN (Wide Area Network).

[0014] In FIG. 1, a case where the X-ray detector 30 is disposed over the entire back side of the imaging table 12 is shown, but the arrangement of the X-ray detector 30 is not limited thereto. For example, an operator (such as a doctor or a technician) performing X-ray imaging may change the position where an X-ray detector 30 of a predetermined size (for example, an X-ray detector 30 having a 40 [cm] square) is installed on the back surface of the imaging table 12 in accordance with the direction in which the X-rays are irradiated from the X-ray source 20, that is, move the X-ray detector 30 for each X-ray image capture, so that the entire range of the imaging table 12 can be imaged. Further, the X-ray detector 30 may be disposed at a position close to the floor surface of the imaging room, for example, as long as it is a position where the X-rays r that have passed through the patient P's body can be detected in a state where the focus is fixed on the back side of the imaging table 12, that is, the position where the X-rays r that have passed through the patient P's body can be detected. The X-ray detector 30 may detect the X-rays r that have been irradiated from the X-ray source 20, passed through the patient P's body, and reached, and output a detection signal representing the magnitude of the energy of the detected X-rays r to the medical image processing apparatus 100. In this case, the X-ray image is generated by the medical image processing apparatus 100.

[0015] The medical image processing apparatus 100 generates a long X-ray image based on the X-ray image output by the X-ray detector 30. At this time, the medical image processing apparatus 100 determines whether the generated long X-ray image includes a deviation caused by the body movement of the patient P during imaging. The medical image processing apparatus 100 causes the display device 200 to display a display image for presenting the generated long X-ray image and information indicating the result of determining the presence or absence of deviation due to the body movement of the patient P to the X-ray diagnosis performer or the X-ray imaging performer (hereinafter, the X-ray diagnosis performer and the X-ray imaging performer are not distinguished and are collectively referred to as the "X-ray diagnosis performer").

[0016] The display device 200 is, for example, a liquid crystal display (LCD), a CRT (Cathode Ray Tube) display, an organic EL (Electroluminescence) display, or the like. The display device 200 may be a desktop type connected to the medical image processing apparatus 100, or may be a display device (for example, a tablet terminal) capable of wireless communication with the medical image processing apparatus 100. The X-ray diagnosis performer can obtain information on the long X-ray image taken by the X-ray diagnostic apparatus 1 and whether body movement occurred in the patient P during the shooting of this long X-ray image by visually checking the display image displayed on the display device 200.

[0017] [Functional Configuration of Medical Image Processing Apparatus] The medical image processing apparatus 100 includes, for example, an irradiation control unit 120 and a processing circuit 140. The processing circuit 140 executes processes such as an image acquisition function 141, an image processing function 142, an overlap region specifying function 143, a preprocessing function 144, a body movement index calculation function 145, a body movement index determination function 146, and a display control function 147.

[0018] The processing circuit 140 realizes each of the functions of the image acquisition function 141, the image processing function 142, the overlap area specifying function 143, the preprocessing function 144, the body movement index calculation function 145, the body movement index determination function 146, and the display control function 147, for example, by executing a program (software) stored in a memory (storage unit), not shown, by a hardware processor. The memory, not shown, is realized by, for example, a semiconductor memory element such as a ROM (Read Only Memory), a RAM (Random Access Memory), or a flash memory, a hard disk drive (HDD), an optical disk, or the like.

[0019] A hardware processor means circuitry such as, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an LSI (Large Scale Integration), an application specific integrated circuit (ASIC), a programmable logic device (e.g., a simple programmable logic device (SPLD) or a complex programmable logic device (CPLD), a field programmable gate array (FPGA)). Instead of storing a program in a memory (not shown), it may be configured to directly incorporate the program into the circuitry of the hardware processor. In this case, the hardware processor realizes each function by reading and executing the program incorporated in the circuitry. The hardware processor is not limited to being configured as a single circuit, and may be configured as one hardware processor by combining a plurality of independent circuits to realize each function. A plurality of components may be integrated into one hardware processor to realize each function. A plurality of components may be incorporated into one dedicated LSI to realize each function. Here, the program (software) may be stored in advance in a storage device (a storage device including a non-transitory storage medium) that constitutes a semiconductor memory element such as a ROM, a RAM, or a flash memory, or a storage device such as a hard disk drive (HDD), or may be stored in a removable storage medium (non-transitory storage medium) such as a DVD or a CD-ROM, and may be installed in the storage device provided in the medical image processing apparatus 100 by mounting the storage medium on a drive device provided in the medical image processing apparatus 100. The program (software) may be downloaded in advance from another computer device via a network (not shown) and installed in the storage device provided in the medical image processing apparatus 100.A program (software) installed in a storage device provided in the medical image processing apparatus 100 may be transferred to a processing circuit provided in the medical image processing apparatus 100 and executed. The medical image processing apparatus 100 may be implemented in a server device or a storage device incorporated in a cloud computing system. In this case, the functions of the medical image processing apparatus 100 may be implemented by a plurality of server devices and storage devices in the cloud computing system.

[0020] The irradiation control unit 120 controls the irradiation of X-rays from the X-ray source 20. When taking a long X-ray image in the X-ray diagnostic apparatus 1, the irradiation control unit 120 changes the irradiation angle of the X-rays irradiated from the X-ray source 20 to the patient P to an angle corresponding to each X-ray image constituting the long X-ray image. At this time, the irradiation control unit 120 changes the irradiation angle of the X-rays irradiated from the X-ray source 20 so that a part of each X-ray image overlaps, that is, so that a part of the irradiation range of each X-ray overlaps. In FIG. 1, an example of the configuration is shown when the irradiation control unit 120 is a component of the medical image processing apparatus 100, but the irradiation control unit 120 may be realized by a hardware configuration different from that of the medical image processing apparatus 100. In this case, the irradiation control unit 120 may notify the processing circuit 140 of the timing of irradiating X-rays to take each X-ray image, in other words, the timing of obtaining an X-ray image from the X-ray detector 30.

[0021] The image acquisition function 141 acquires the X-ray image output by the X-ray detector 30. When taking a long X-ray image in the X-ray diagnostic apparatus 1, the image acquisition function 141 acquires each X-ray image output by the X-ray detector 30 each time X-rays are irradiated from the X-ray source 20 in accordance with the control of the irradiation control unit 120. In FIG. 1, three X-ray images corresponding to the X-rays r-1, r-2, and r-3 irradiated by the X-ray source 20 are acquired. The image acquisition function 141 outputs each acquired X-ray image to each of the image processing function 142, the overlap region specifying function 143, and the preprocessing function 144. The image acquisition function 141 is an example of an "image acquisition unit".

[0022] The image processing function 142 stitches together each X-ray image output by the image acquisition function 141 to generate a long X-ray image. More specifically, the image processing function 142 sequentially performs image processing using, for example, existing image synthesis techniques on each X-ray image output by the image acquisition function 141 to generate a long X-ray image. The image processing function 142 outputs the generated long X-ray image to the display control function 147. The image processing function 142 may output (transmit) the generated long X-ray image to a database system such as a medical image management system (PACS: Picture Archiving and Communication Systems) that manages data of various medical images, or an electronic medical record system that manages electronic medical records with information such as X-ray images (which may include long X-ray images) of past X-ray diagnoses attached. The image processing function 142 is an example of an "image processing unit".

[0023] The overlap region specifying function 143 specifies the overlap regions included in the respective X-ray images output by the image acquisition function 141. The overlap region is a region where the same position state in the body of the patient P is imaged in two temporally consecutive X-ray images output by the image acquisition function 141, due to a part of the X-ray irradiation range being overlapped when the irradiation control unit 120 changes the irradiation angle of the X-rays irradiated to the X-ray source 20. The overlap region specifying function 143 specifies the overlap region for each X-ray image. More specifically, when taking three X-ray images as shown in FIG. 1, the overlap region specifying function 143 specifies the overlap region between the first X-ray image and the second X-ray image, and further specifies the overlap region between the second X-ray image and the third X-ray image. The specification of the overlap region in the overlap region specifying function 143 can be performed by joining (pasting) the in-body images of the patient P shown in two consecutive X-ray images according to geometric conditions (for example, the shape of the in-body image and the shape of the boundary part (so-called edge part)). At this time, the overlap region specifying function 143 grasps in advance the mechanical displacement of the in-body image that is assumed to occur when each X-ray image is taken (a displacement different from the displacement caused by the body movement of the patient P), and the calculation for correcting this mechanical displacement of the in-body image may be included in the geometric conditions when specifying the overlap region. The overlap region specifying function 143 outputs information representing the specified overlap region to the body movement index calculation function 145. The information representing the overlap region is, for example, information representing the width of the overlap region included in the X-ray image (in an example shown in FIG. 1, the length or the number of pixels in the Y-axis direction). The overlap region specifying function 143 is an example of an "overlap region specifying unit".

[0024] The preprocessing function 144 performs predetermined image processing on each of the X-ray images output by the image acquisition function 141 as preprocessing (prior processing). The predetermined image processing is, for example, luminance value correction processing or feature extraction processing. The luminance value correction processing is a process of correcting the luminance value of the pixels forming each X-ray image. For example, if the pixel values differ between the first X-ray image and the second X-ray image, the difference in these pixel values (the difference in luminance values) may affect X-ray diagnosis. Therefore, it is a process of correcting so that the luminance values of each X-ray image become equivalent. The feature extraction processing is a process of detecting the boundary part (edge part) of the in-vivo image shown in the X-ray image. For example, it is a preprocessing (prior processing) when calculating the degree of coincidence of the overlap region between the first X-ray image and the second X-ray image. The feature extraction processing may be performed as part of the processing performed by the body movement index calculation function 145 described later to calculate the body movement index of the patient P. The preprocessing function 144 outputs the X-ray images subjected to preprocessing (prior processing) to each of the image processing function 142 and the overlap region specifying function 143. In this case, the image processing function 142 may generate a long X-ray image by joining together each of the X-ray images preprocessed by the preprocessing function 144. Further, the overlap region specifying function 143 may specify the overlap region included in each of the X-ray images preprocessed by the preprocessing function 144. If each of the image processing function 142 and the overlap region specifying function 143 does not perform corresponding alignment on each of the X-ray images preprocessed by the preprocessing function 144, the preprocessing function 144 may be omitted. That is, the preprocessing function 144 does not necessarily have to be a function provided in the processing circuit 140. The preprocessing function 144 is an example of a "preprocessing unit".

[0025] The body movement index calculation function 145 calculates a body movement index, which is an index for determining whether or not body movement has occurred in the patient P during the X-ray image acquisition, based on the information representing the overlapping area output by the overlapping area specifying function 143, for the internal images shown in two consecutive X-ray images. The body movement index may be any numerical value that represents, for example, the degree of coincidence or deviation of the internal images shown in the overlapping area, the amount of movement or deviation by which the patient P has moved during the acquisition. The body movement index may be obtained, for example, by calculating the cross-correlation coefficient between the internal images shown in the overlapping area, or by performing a motion estimation process using optical flow. The body movement index may be obtained, for example, using an algorithm for aligning the internal images, similar to the process when the image processing function 142 stitches together X-ray images to generate a long X-ray image. In this case, the body movement index calculation function 145 may obtain information on the amount of deformation or movement of the X-ray image obtained when stitching together the X-ray images from the image processing function 142, and determine the body movement index based on the obtained information on the amount of deformation or movement, or the obtained amount of deformation or movement may be used as the body movement index. The body movement index calculation function 145 outputs the obtained body movement index information to the body movement index determination function 146. The body movement index calculation function 145 is an example of a "body movement index calculation unit".

[0026] The body movement index determination function 146 determines whether or not body movement that may affect the X-ray diagnosis of the patient P has occurred based on the information on the body movement index output by the body movement index calculation function 145. For example, the body movement index determination function 146 determines whether or not body movement has occurred based on whether or not the body movement index output by the body movement index calculation function 145 is less than or equal to a specified value. Here, the specified value for determining whether or not body movement has occurred may be automatically set for each imaging measurement condition when taking a long X-ray image and each surgical procedure (e.g., entire lower limb, entire spine) determined based on the long X-ray image, or may be set by the X-ray diagnosis operator before starting the imaging of the long X-ray image. The body movement index determination function 146 adds information representing the result (determination result) of determining whether or not body movement has occurred to the information on the body movement index output by the body movement index calculation function 145 and outputs it to the display control function 147. In the following description, in order to distinguish between the information on the body movement index output by the body movement index calculation function 145 and the information on the body movement index with the information representing the determination result added, the information on the body movement index with the information representing the determination result added is referred to as the "determined body movement index". The body movement index determination function 146 is an example of a "body movement index determination unit".

[0027] The display control function 147 generates a display image for presenting to the X-ray diagnosis operator by associating the long X-ray image output by the image processing function 142 with the determined body movement index output by the body movement index determination function 146. The display control function 147 may add notification information such as a message for prompting the X-ray diagnosis operator or proposing re-imaging of the long X-ray image to the display image based on the result of determining whether or not the body movement of the patient P represented by the determined body movement index has occurred. The display control function 147 outputs the generated display image to the display device 200 for display. The display control function 147 is an example of a "display control unit".

[0028] [Operation of Medical Imaging Processing Apparatus] Next, the determination of the presence or absence of the patient P's body movement in the medical imaging apparatus 100 and the operation of presenting the determination result will be described. In the following description, it is assumed that the X-ray diagnostic apparatus 1 takes three X-ray images to generate a long X-ray image.

[0029] First, an example of the X-ray image taken by the X-ray diagnostic apparatus 1 will be described. FIG. 2 is a diagram showing an example of the positional relationship between the imaging range of the X-ray image taken by the X-ray diagnostic apparatus 1 according to the embodiment and the subject. Each X-ray image FI shown in FIG. 2 is an example of an X-ray image generated when the irradiation control unit 120 rotates the X-ray source 20 in the Y-axis direction to irradiate each X-ray r to the patient P, and the X-ray detector 30 detects it. The X-ray image FI-1 shown in FIG. 2(a) is an X-ray image generated by detecting the X-ray r-1 irradiated to the patient P, and the X-ray image FI-2 shown in FIG. 2(b) is an X-ray image generated by detecting the X-ray r-2 irradiated to the patient P. The X-ray image FI-3 shown in FIG. 2(c) is an X-ray image generated by detecting the X-ray r-3 irradiated to the patient P. Here, since the X-rays r-1, r-2, and r-3 are irradiated by rotating the X-ray source 20 in the Y-axis direction, originally, the positions of the X-ray images FI-1, FI-2, and FI-3 in the X-axis direction should be the same position. However, FIG. 2 schematically shows an example in which the patient P has moved during the imaging interval (imaging interval) between each X-ray image FI. For example, taking the X-ray image FI-1 as a reference, it shows an example of a state in which the X-ray image FI-2 is taken when the patient P moves to the right, and then the X-ray image FI-3 is taken when the patient P moves to the left.

[0030] The X-ray image FI-1 is an example of the "first X-ray image", and the X-ray image FI-2 is an example of the "second X-ray image". The X-ray image FI-3 is an example of the "second X-ray image" continuously taken later in time than the X-ray image FI-2 when the X-ray image FI-2 is regarded as an example of the "first X-ray image".

[0031] Next, the process of body movement determination by the processing circuit 140 included in the medical image processing apparatus 100 will be described. However, in the following description, details of the process in which the image processing function 142 generates a long X-ray image by image processing using, for example, an existing image synthesis technique will be omitted. FIG. 3 is a flowchart showing an example of the flow of a process for notifying a body movement index of a subject (patient P) in the medical image processing apparatus 100 included in the X-ray diagnostic apparatus 1 according to the embodiment. In the body movement determination process of the flowchart shown in FIG. 3, when generating a long X-ray image in the X-ray diagnostic apparatus 1, from the start of shooting the first X-ray image (here, X-ray image FI-1), the processing of each function is executed in the processing circuit 140.

[0032] When starting the body movement determination process, the processing circuit 140 initializes a variable n for managing the number of X-ray images taken (n = 1) (step S100). Then, the image acquisition function 141 acquires the n-th X-ray image output by the X-ray detector 30 (step S102). Here, the image acquisition function 141 acquires the first X-ray image FI-1 with n = 1. The image acquisition function 141 outputs the acquired X-ray image FI-1 to each of the image processing function 142, the overlap region specifying function 143, and the preprocessing function 144.

[0033] Thereafter, the processing circuit 140 increments the variable n (n = n + 1) (step S110). Then, the image acquisition function 141 acquires the n-th X-ray image output by the X-ray detector 30 (step S112). Here, the image acquisition function 141 acquires the second X-ray image FI-2 with n = 2. The image acquisition function 141 outputs the acquired X-ray image FI-2 to each of the image processing function 142, the overlap region specifying function 143, and the preprocessing function 144.

[0034] The overlap region specifying function 143 specifies the overlap region between the n-th X-ray image output by the image acquisition function 141 and the (n - 1)-th X-ray image (step S120). Here, the overlap region specifying function 143 specifies the overlap region between the second X-ray image FI-2 and the first X-ray image FI-1 (where n = 2 and n - 1 = 1). The overlap region specifying function 143 outputs information representing the specified overlap region to the body movement index calculation function 145.

[0035] Here, when the processing circuit 140 includes the preprocessing function 144, the preprocessing function 144 performs preprocessing on each of the X-ray images output by the image acquisition function 141 (here, the X-ray image FI-1 and the X-ray image FI-2) (step S130). The processing in step S130 in this preprocessing function 144 may be performed simultaneously with the processing in step S120 in the overlap region specifying function 143. As described above, when the preprocessing function 144 is omitted, the processing in step S130 may not be performed.

[0036] Thereafter, based on the information representing the overlap region output by the overlap region specifying function 143, the body movement index calculation function 145 calculates the body movement indices corresponding to two consecutive X-ray images (here, the X-ray image FI-1 and the X-ray image FI-2) (step S140). The body movement index calculation function 145 outputs the information on the calculated body movement indices to the body movement index determination function 146.

[0037] Here, an example of specifying the overlap region by the overlap region specifying function 143 and calculating the body movement index by the body movement index calculating function 145 will be described. FIG. 4 is a diagram showing an example of the overlap region in each X-ray image taken by the X-ray diagnostic apparatus 1 according to the embodiment. FIG. 4(a) schematically shows an example of a long X-ray image generated by connecting the X-ray images FI-1, FI-2, and FI-3. And, FIG. 4(b) schematically shows the processing of the overlap region specifying function 143 and the body movement index calculating function 145 corresponding to the X-ray image FI-1 and the X-ray image FI-2, and FIG. 4(c) schematically shows the processing of the overlap region specifying function 143 and the body movement index calculating function 145 corresponding to the X-ray image FI-2 and the X-ray image FI-3.

[0038] FIG. 4(b-1) shows the overlap region OL-1 of the X-ray image FI-1 specified by the overlap region specifying function 143 in the process of step S120 and the overlap region OU-2 of the X-ray image FI-2. The body movement index calculating function 145 calculates the body movement index between the in-vivo image shown in the overlap region OL-1 and the in-vivo image shown in the overlap region OU-2 in the process of step S140. FIG. 4(b-2) shows an example when the displacement amount between the overlap region OL-1 and the overlap region OU-2 is calculated and obtained as the body movement index MI-1-2. The body movement index calculating function 145 outputs the obtained body movement index MI-1-2 (displacement amount) to the body movement index determination function 146.

[0039] Returning to FIG. 3, the body movement index determination function 146 determines whether the body movement index MI-1-2 (deviation amount) output by the body movement index calculation function 145 is equal to or less than a specified value (step S150). In step S150, if it is determined that the body movement index MI-1-2 (deviation amount) is equal to or less than the specified value, that is, no body movement that may affect the X-ray diagnosis of the patient P has occurred, the body movement index determination function 146 outputs the body movement index MI-1-2 (deviation amount) output by the body movement index calculation function 145 to the display control function 147 as a determined body movement index, and advances the process to step S160.

[0040] On the other hand, in step S150, if it is determined that the body movement index MI-1-2 (deviation amount) is not equal to or less than the specified value, that is, body movement that may affect the X-ray diagnosis of the patient P has occurred, the body movement index determination function 146 adds information representing the determination result to the body movement index MI-1-2 (deviation amount) output by the body movement index calculation function 145 (step S152). Then, the body movement index determination function 146 outputs the determined body movement index with the information representing the determination result added thereto to the display control function 147.

[0041] Then, the processing circuit 140 checks whether the current variable n is the number of X-ray images to be taken for generating the long X-ray image (step S160). In step S160, if it is confirmed that the current variable n is the number of the last X-ray image to be taken, that is, all the X-ray images (acquisition) used for generating the long X-ray image have been taken, the processing circuit 140 advances the process to step S170.

[0042] On the other hand, in step S160, if it is confirmed that the current variable n is not the number of the last X-ray image to be taken, that is, all the X-ray images (acquisition) used for generating the long X-ray image have not been taken, the processing circuit 140 returns the process to step S110 and repeats the processes of steps S110 to S160.

[0043] Here, in order to generate a long X-ray image by taking three X-ray images, since the current variable n is n = 2, the processing circuit 140 returns the process to step S110. Then, in the second execution of step S110, the processing circuit 140 increments the variable n (n = n + 1). As a result, the image acquisition function 141 acquires the third X-ray image FI-3 with n = 3 in the second execution of step S112, and outputs the acquired X-ray image FI-3 to each of the image processing function 142, the overlap region specifying function 143, and the preprocessing function 144.

[0044] In the second execution of step S120, the overlap region specifying function 143 specifies the overlap region between the third X-ray image FI-3 with n = 3 and the second X-ray image FI-2 with n = 3 - 1 = 2, and outputs information representing the specified overlap region to the body movement index calculation function 145.

[0045] Thereafter, in the second execution of step S140, the body movement index calculation function 145 calculates the body movement indices corresponding to the X-ray images FI-2 and FI-3, and outputs information on the calculated body movement indices to the body movement index determination function 146.

[0046] Fig. 4(c-1) shows the overlap region OL-2 of the X-ray image FI-2 and the overlap region OU-3 of the X-ray image FI-3 specified by the overlap region specifying function 143 in the second execution of step S120. In the second execution of step S140, the body movement index calculation function 145 calculates the body movement index between the in-body images shown in the overlap region OL-2 and the in-body images shown in the overlap region OU-3. Fig. 4(c-2) shows an example of the case where the amount of deviation between the overlap region OL-2 and the overlap region OU-3 is calculated and obtained as the body movement index MI-2-3. The body movement index calculation function 145 outputs the obtained body movement index MI-2-3 (amount of deviation) to the body movement index determination function 146.

[0047] Returning to FIG. 3, in the process of the second step S150, similar to the process of the first step S150, the body movement index determination function 146 determines whether the body movement index MI-2-3 (deviation amount) output by the body movement index calculation function 145 is less than or equal to a specified value, and outputs the determined body movement index according to the determination result to the display control function 147.

[0048] Then, in the process of the second step S160, the processing circuit 140 checks whether the current variable n is the number of X-ray images taken for generating the long X-ray image, and according to the check result, repeats the processes of steps S110 to S160 again, or advances the process to step S170.

[0049] Here, three X-ray images are taken to generate a long X-ray image. Since the current variable n is n = 3, the processing circuit 140 advances the process to step S170. Then, the display control function 147 generates a display image including the determined body movement index (including notification information) output by the body movement index determination function 146 and displays it on the display device 200 to present it to the operator performing the X-ray diagnosis (step S170).

[0050] Here, an example of the display image generated by the display control function 147 and displayed on the display device 200 will be described. FIG. 5 is a diagram showing an example of a display image presenting the body movement index of the subject (patient P) in the X-ray diagnostic apparatus 1 according to the embodiment. In the display image IM shown in FIG. 4, the long X-ray image CI output by the image processing function 142 is presented. And in the display image IM, at the location corresponding to the overlap region between the X-ray image FI-1 and the X-ray image FI-2 that constitute the long X-ray image CI, the body movement index MI-1-2 (displacement amount) represented by the determined body movement index output by the body movement index determination function 146 is superimposed and presented. Further, in the display image IM, at the location corresponding to the overlap region between the X-ray image FI-2 and the X-ray image FI-3 that constitute the long X-ray image CI, the body movement index MI-2-3 (displacement amount) represented by the determined body movement index output by the body movement index determination function 146 is superimposed and presented. Here, in the display image IM, it is assumed that the body movement index MI-2-3 (displacement amount) is not less than the specified value, that is, it is determined that body movement that may affect the X-ray diagnosis of the patient P has occurred. For this reason, in the display image IM, at the location corresponding to the body movement index MI-2-3 (displacement amount), as notification information, a caution icon Ia that prompts the operator of the X-ray diagnosis to pay attention is displayed, and further, a message such as "The body movement is large." and a message that proposes re-shooting the long X-ray image CI, such as "There is a possibility that it is not suitable for diagnosis. Please consider re-shooting." are displayed. Thereby, the operator of the X-ray diagnosis can recognize that significant body movement has occurred in the patient P between the shooting of the X-ray image FI-2 and the shooting of the X-ray image FI-3 based on the notification information presented in the display image IM. And the operator of the X-ray diagnosis can check the message displayed in the display image IM and determine whether to perform re-shooting of the long X-ray image CI.

[0051] As described above, in the X-ray diagnostic apparatus according to the embodiment, when generating a long X-ray image by connecting a plurality of X-ray images taken in a state where the focal point is fixed, the medical image processing apparatus is based on the internal image of the patient P shown in the overlap region where a part of each X-ray image overlaps, and determines whether or not each X-ray image includes a deviation caused by the body movement of the subject (patient). Then, in the X-ray diagnostic apparatus according to the embodiment, the medical image processing apparatus presents (notifies) the determination result to the person performing the X-ray diagnosis. In other words, in the X-ray diagnostic apparatus according to the embodiment, the medical image processing apparatus presents information regarding the quality of the generated long X-ray image to the person performing the X-ray diagnosis. As a result, an operator such as a doctor or a technician who performs X-ray diagnosis using the X-ray diagnostic apparatus according to the embodiment can recognize whether or not body movement that may affect the patient's X-ray diagnosis has occurred in the generated long X-ray image, and further, can recognize in which of the X-ray images taken to generate the long X-ray image the body movement has occurred. By this, the operator of the X-ray diagnosis using the X-ray diagnostic apparatus according to the embodiment can determine whether to re-take the long X-ray image and perform X-ray diagnosis after recognizing the body movement of the patient, and can more preferably perform the diagnosis of the patient.

[0052] In the above-described embodiment, the case where the medical image processing apparatus 100 acquires all the X-ray images constituting the long X-ray image, calculates the body movement index, and makes a determination based on the specified value, and then causes the display apparatus 200 to display the display image has been described. However, the display of the display image on the display apparatus 200 may be performed at the time when the calculation of the body movement index corresponding to the X-ray images acquired up to the present time and the determination based on the specified value are completed, and each time the next X-ray image is acquired and the calculation of the body movement index and the determination based on the specified value are completed, the display image may be updated accordingly. In this case, the X-ray diagnosis practitioner using the X-ray diagnostic apparatus 1 can determine whether to re-take the long X-ray image when body movement that may affect the X-ray diagnosis of the patient P occurs. In other words, when significant body movement occurs during the shooting of the X-ray image for generating the long X-ray image, the current shooting can be stopped. This leads to a reduction in the X-ray exposure dose to the patient P even when it becomes necessary to re-take the long X-ray image, which is more preferable. Further, when significant body movement occurs during the shooting of the X-ray image for generating the long X-ray image, it becomes possible to stop the output (transmission) of the generated long X-ray image to a database system such as a medical image management system or an electronic medical record system. This leads to avoiding an increase in the load caused by outputting (transmitting) the long X-ray image that is not used for the X-ray diagnosis of the patient P when it becomes necessary to re-take the long X-ray image, which is more preferable. Since the configurations, operations, and processes of the X-ray diagnostic apparatus 1 and the medical image processing apparatus 100 in this case can be easily conceived, detailed description thereof is omitted.

[0053] In the above-described embodiment, the case where the X-ray diagnostic apparatus 1 changes the direction of irradiating X-rays by rotating the X-ray source 20 and captures a plurality of X-ray images in a state where the focal point is fixed has been described. However, the configuration for capturing a plurality of X-ray images in a state where the focal point is fixed in the X-ray diagnostic apparatus 1 is not limited to the configuration described in the embodiment. For example, a configuration in which a plurality of X-ray images are captured in a state where the focal point is fixed by narrowing down the irradiation range of X-rays using a collimator may be used. In this case, the configuration, operation, and processing of the X-ray diagnostic apparatus may be made equivalent to the configuration, operation, and processing of the X-ray diagnostic apparatus 1 of the above-described embodiment. Therefore, detailed descriptions of the configuration, operation, and processing of the X-ray diagnostic apparatus when the method of capturing a plurality of X-ray images is different are omitted.

[0054] In the above-described embodiment, the case where a long X-ray image is generated by irradiating a patient P with X-rays has been described. However, the diagnosis using a long medical image performed on the patient P is not limited to the X-ray diagnostic apparatus 1 using X-rays described in the embodiment. That is, the long medical image may be captured using radiation other than X-rays. In this case, the configuration, operation, and processing of the medical diagnostic apparatus may be made equivalent to the configuration, operation, and processing of the X-ray diagnostic apparatus 1 of the above-described embodiment. Therefore, detailed descriptions of the configuration, operation, and processing of the medical diagnostic apparatus that captures images using radiation other than X-rays are omitted.

[0055] The above-described embodiment can be expressed as follows. Comprising a processing circuitry, The processing circuitry, Causes the X-ray to be irradiated from an X-ray source that irradiates the subject with X-rays while varying the irradiation angle, and is disposed at a position facing the X-ray source. While the positional relationship with the X-ray source is fixed, a plurality of time-continuously captured X-ray images generated based on the X-rays with different irradiation angles detected by an X-ray detector that detects the X-rays that have passed through the subject are acquired. Based on the in-vivo images of the subject captured in the first X-ray image and the second X-ray image that are temporally continuous among the plurality of X-ray images, a body movement index representing the body movement of the subject during the imaging between the first X-ray image and the second X-ray image is displayed on a display device. X-ray diagnostic apparatus.

[0056] According to at least one of the embodiments described above, an X-ray source (20) that irradiates X-rays with a variable irradiation angle to a subject (P), an X-ray detector (30) that is disposed at a position facing the X-ray source and detects the X-rays that have passed through the subject in a state where the positional relationship with the X-ray source is fixed, and a plurality of temporally continuous X-ray images (FI) generated based on the X-rays with different irradiation angles detected by the X-ray detector are acquired. Based on the in-vivo images of the subject captured in the first X-ray image (FI-1) and the second X-ray image (FI-2) that are temporally continuous among the plurality of X-ray images, a body movement index (MI-1-2) representing the body movement of the subject during the imaging between the first X-ray image and the second X-ray image is displayed on a display device (200). By having a medical image processing apparatus (100), it is possible to confirm the influence of the body movement of the subject on the X-ray image.

[0057] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0058] 1... X-ray diagnostic apparatus, 10... imaging table apparatus, 12... imaging table, 14... imaging table elevator, 20... X-ray source, 30... X-ray detector, 100... medical image processing apparatus, 120... irradiation control unit, 140... processing circuit, 141... image acquisition function, 142... image processing function, 143... overlap region specifying function, 144... preprocessing function, 145... body movement index calculation function, 146... body movement index determination function, 147... display control function, 200... display device

Claims

1. An X-ray source that irradiates an object with X-rays while varying the irradiation angle, An X-ray detector that is disposed at a position facing the X-ray source, has a fixed positional relationship with the X-ray source, and detects X-rays that have passed through the object and arrived, A medical image processing device that acquires a plurality of X-ray images that are continuously taken over time and generated based on the X-rays with different irradiation angles detected by the X-ray detector, and based on the in-vivo images of the object shown in the first X-ray image and the second X-ray image that are temporally continuous among the plurality of X-ray images, causes a display device to display a body movement index representing the body movement of the object during the imaging between the first X-ray image and the second X-ray image, An X-ray diagnostic apparatus comprising the above.

2. The medical image processing device includes: An image acquisition unit that acquires the first X-ray image and the second X-ray image, An overlap region specifying unit that specifies an overlap region where the in-vivo images overlap in the first X-ray image and the second X-ray image, A body movement index calculation unit that calculates a body movement index representing the degree of deviation of the in-vivo image shown in the overlap region, A body movement index determination unit that determines the body movement index between the first X-ray image and the second X-ray image based on a specified value of the body movement index, A display control unit that controls the display of a display image representing the determination result of the body movement index on the display device, The X-ray diagnostic apparatus according to Claim 1, comprising the above.

3. The medical image processing device further includes: An image processing unit that generates a long X-ray image by connecting the first X-ray image and the second X-ray image, The X-ray diagnostic apparatus according to Claim 2, further comprising the above.

4. The display control unit: Includes the long X-ray image in the display image, and causes the determination result of the body movement index to be displayed at a position corresponding to the overlap region between the first X-ray image and the second X-ray image in the long X-ray image, The X-ray diagnostic apparatus according to Claim 3.

5. The medical image processing device further includes: At least a preprocessing unit that corrects the luminance values of the first X-ray image and the second X-ray image, and The overlap region specifying unit specifies the overlap region in the first X-ray image and the second X-ray image whose luminance values have been corrected, The X-ray diagnostic apparatus according to any one of Claims 2 to 4.

6. The image acquisition unit further acquires a third X-ray image that is taken continuously in time after the second X-ray image. The overlap region specifying unit specifies a second overlap region where the in-vivo images overlap in the second X-ray image and the third X-ray image. The body movement index calculation unit calculates a second body movement index representing the degree of displacement of the in-vivo image shown in the second overlap region. The body movement index determination unit determines the second body movement index during the imaging between the second X-ray image and the third X-ray image based on a specified value of the body movement index. The display control unit causes the display image obtained by adding the determination result of the second body movement index to the display image to be displayed. The X-ray diagnostic apparatus according to claim 5.

7. Irradiating the subject with X-rays from an X-ray source that variably changes the irradiation angle, and being disposed at a position facing the X-ray source and having a fixed positional relationship with the X-ray source, acquiring a plurality of X-ray images that are generated based on the X-rays that have passed through the subject and are detected by an X-ray detector, and that are taken continuously in time, and based on the in-vivo images of the subject shown in the first X-ray image and the second X-ray image that are temporally continuous among the plurality of X-ray images, causing a display device to display a body movement index representing the body movement of the subject during the imaging between the first X-ray image and the second X-ray image. Medical image processing apparatus.

8. On a computer of a medical image processing apparatus, causing the subject to be irradiated with X-rays from an X-ray source that variably changes the irradiation angle, and acquiring a plurality of X-ray images that are generated based on the X-rays that have passed through the subject and are detected by an X-ray detector, which is disposed at a position facing the X-ray source and has a fixed positional relationship with the X-ray source, and that are taken continuously in time, and based on the in-vivo images of the subject shown in the first X-ray image and the second X-ray image that are temporally continuous among the plurality of X-ray images, causing a display device to display a body movement index representing the body movement of the subject during the imaging between the first X-ray image and the second X-ray image. Program.

Images