Moving image processing device, moving image processing method, and computer program product

Abstract

The invention relates to a moving image processing device, a moving image processing method and a computer program product, and provides a moving image processing device capable of acquiring a moving image suitable for dynamic analysis processing. A dynamic analysis device is provided with: a first generation unit that generates a dose waveform including blood flow fluctuations and respiratory fluctuations in a region of interest in each frame image constituting a dynamic image obtained by dynamic imaging by radiation; an extraction unit that extracts, from the dose waveform generated by the first generation unit, a frame waveform including random body movement fluctuations that differ from blood flow fluctuations and respiratory fluctuations; and a second generation unit that generates information indicating that the waveform information extracted by the extraction unit is a moving image that is not suitable for dynamic analysis.

Description

Technical Field

[0001] This invention relates to a dynamic image processing apparatus, a dynamic image processing method, and a computer program product. Background Technology

[0002] Clinical research utilizing dynamic analysis based on X-ray dynamic images is progressing, and dynamic analysis is being applied in the examination of various diseases. For example, dynamic analysis processing using X-ray dynamic images to analyze blood flow such as pulmonary blood flow and cardiac blood flow has been developed. Patent Document 1 describes a dynamic image analysis device that generates information related to pulmonary valve regurgitation based on dynamic images of a region of interest such as the pulmonary artery or heart.

[0003] Patent Document 1: Japanese Patent No. 7424423

[0004] However, dynamic images can contain noise due to unpredictable bodily movements such as coughing and respiratory changes such as breathing and arrhythmia. While previous techniques could generate information such as pulmonary valve regurgitation from dynamic images, they could not extract the noise caused by bodily movements. Therefore, when performing dynamic analysis using dynamic images containing noise caused by bodily movements, it is difficult to obtain appropriate analysis results. Summary of the Invention

[0005] Therefore, in order to solve the above-mentioned problems, the present invention aims to provide a dynamic image processing apparatus, a dynamic image processing method, and a computer program product capable of acquiring dynamic images suitable for dynamic analysis and processing.

[0006] The dynamic image processing apparatus of the present invention comprises:

[0007] The first generation unit generates waveform information containing blood flow and respiratory changes within a defined region of each frame image, wherein each frame image constitutes a dynamic image obtained through radiation-based dynamic imaging; and

[0008] The extraction unit extracts waveform information containing dose variations that differ from the blood flow variations and respiratory variations from the waveform information generated by the first generation unit.

[0009] The dynamic image processing method involved in this invention has the following characteristics:

[0010] The first generation step involves generating waveform information containing blood flow and respiratory changes within a defined region of each frame image, wherein each frame image constitutes a dynamic image obtained through radiation-based dynamic imaging; and

[0011] In the extraction step, waveform information containing dose variations that differ from the aforementioned blood flow variations and respiratory variations is extracted from the generated waveform information.

[0012] The computer program product involved in this invention enables a computer to be used as:

[0013] The first generation unit generates waveform information containing blood flow and respiratory changes within a defined region of each frame image, wherein each frame image constitutes a dynamic image obtained through radiation-based dynamic imaging; and

[0014] The extraction unit extracts waveform information containing dose variations that differ from the blood flow variations and respiratory variations from the waveform information generated by the first generation unit.

[0015] According to the present invention, waveform information containing noise caused by changes in the patient's body movement can be extracted from waveform information, and therefore, a prescribed dynamic analysis can be performed using appropriate dynamic images. Attached Figure Description

[0016] Figure 1 This is a diagram illustrating an example of the general structure of the image capturing system according to this embodiment.

[0017] Figure 2 This is a diagram showing a frame image of a dynamic image in which a region of interest is defined, according to this embodiment.

[0018] Figure 3 It is a dose waveform that represents the change in signal value of a pixel in the region of interest of the dynamic image involved in this embodiment.

[0019] Figure 4 This is a flowchart illustrating an example of the operation of a dynamic analysis device, as described in this embodiment, in the case of extracting noise caused by body motion changes from waveform information representing dose changes in a region of interest of a dynamic image.

[0020] Figure 5 This is a flowchart illustrating an example of the operation of the control unit during the first process involved in this embodiment.

[0021] Figure 6 This is a diagram showing the dose waveform with a reference frame waveform set according to this embodiment.

[0022] Figure 7 This is a diagram showing the dose waveform with a comparison frame waveform set according to this embodiment.

[0023] Figure 8 This is a flowchart illustrating an example of the operation of the control unit during the second processing involved in this embodiment.

[0024] Figure 9 This is a diagram showing the dose waveform of the region of interest in a dynamic image of a dynamic image in this embodiment, where the first frame waveform, the second frame waveform, the third frame waveform, and the fourth frame waveform are set according to each respiratory cycle.

[0025] Explanation of reference numerals in the attached figures: 3…Dynamic analysis device (dynamic image processing device); 31…Control unit (first generation unit, extraction unit, second generation unit, setting unit); FS…Reference frame waveform (first waveform information); Fa, Fb, Fc, Fd, Fe, Ff, Fg…Comparison frame waveform (second waveform information); R…Region of interest (specified region). Detailed Implementation

[0026] Hereinafter, with reference to the accompanying drawings, the preferred embodiments of the present disclosure will be described in detail, including the motion image processing apparatus, motion image processing method, and computer program product.

[0027] [Structure example of image capturing system 100]

[0028] Figure 1 This diagram illustrates an example of the schematic structure of the image capturing system 100 according to this embodiment. The image capturing system 100 includes an capturing device 1, a control console 2, and a motion analysis device 3, which is an example of a motion image processing device. The capturing device 1, the control console 2, and the motion analysis device 3 are connected and can communicate, for example, via a network N such as a LAN (Local Area Network). The communication method of the network N can be wired communication or wireless communication.

[0029] The imaging device 1 captures dynamic images of a predetermined portion of the subject. The control console 2 controls the radiographic imaging based on the imaging device 1 and controls the reading of the radiographic images based on the imaging device 1. The dynamic analysis device 3 performs predetermined dynamic analysis processing on the dynamic images sent from the control console 2, etc. In this embodiment, before performing dynamic analysis processing, the dynamic analysis device 3 extracts a frame waveform composed of multiple frame images containing noise caused by body movement and other variations of the subject M within a predetermined area containing the dynamic image. Each device constituting the image capturing system 100 is based on the DICOM (Digital Image and Communications in Medicine) standard, and communication between the devices is performed according to the DICOM standard.

[0030] [Example of the structure of imaging device 1]

[0031] The imaging device 1 is capable of dynamically capturing, for example, the morphological changes of lung expansion and contraction accompanying respiratory movements, and the beating of the heart. Dynamic imaging refers to repeatedly irradiating a subject M with X-rays or other radiation in a pulsed manner at predetermined time intervals during a single imaging operation, thereby acquiring a series of images of the subject M. Repeatedly irradiating a subject M with pulsed radiation at predetermined time intervals is called pulsed irradiation. Alternatively, dynamic imaging refers to continuously irradiating a subject M with a low dose rate at a single imaging operation, thereby acquiring a series of images of the subject M. Continuously irradiating a subject M without interruption is called continuous irradiation. The series of images obtained through dynamic imaging is called a dynamic image. Furthermore, each image in the entire dynamic image is called a frame image. Here, although dynamic imaging includes capturing motion images, it does not include capturing still images while displaying motion images. Similarly, although dynamic images include motion images, it does not include images obtained by simultaneously capturing still images while displaying motion images.

[0032] like Figure 1 As shown, the imaging device 1 includes a radiation source 11, a radiation irradiation control device 12, a radiation detection unit 13, and a reading control device 14. The radiation irradiation control device 12 and the reading control device 14 are connected via a communication cable or the like, and the radiation irradiation operation and the image reading operation are synchronized by exchanging synchronization signals with each other. Alternatively, the radiation detection unit 13 and the reading control device 14 can be integrated into one unit.

[0033] A radiation source 11 is positioned opposite the radiation detection unit 13, sandwiching the subject M. The radiation source 11 irradiates the subject M with X-rays or other radiation under the control of a radiation irradiation control device 12. The radiation irradiation control device 12 is connected to a control console 2. The radiation irradiation control device 12 controls the radiation source 11 to perform radiation imaging based on radiation irradiation conditions input from the control console 2. Radiation irradiation conditions input from the control console 2 include, for example, pulse rate, pulse width, pulse interval, number of frames per image, X-ray tube current value, X-ray tube voltage value, and type of additional filter. The pulse rate is the number of radiation irradiations per second, consistent with the frame rate described later. The pulse width is the radiation irradiation time for each radiation irradiation. The pulse interval is the time from the start of one radiation irradiation to the start of the next radiation irradiation, consistent with the frame interval described later.

[0034] The radiation detection unit 13 is composed of a semiconductor image sensor such as an FPD (Flat Panel Detector). The FPD has a substrate made of glass or the like. Multiple detection elements, including pixels, are arranged in a matrix at predetermined positions on the substrate. The multiple detection elements detect radiation irradiated from the radiation source 11 and at least transmitted through the subject M according to its intensity, convert the detected radiation into an electrical signal, and store it. Each pixel has a switching unit such as a TFT (Thin Film Transistor). FPDs can be of the indirect conversion type or the direct conversion type, but any type can be used. The indirect conversion type converts radiation into an electrical signal via a scintillator and a photoelectric conversion element. The direct conversion type directly converts radiation into an electrical signal.

[0035] The reading control device 14 is connected to the console 2. The reading control device 14 controls the switching of each pixel of the radiation detection unit 13 based on image reading conditions input from the console 2. The reading control device 14 controls the switching of the reading of electrical signals accumulated in each pixel of the radiation detection unit 13, acquiring image data by reading the electrical signals accumulated in the radiation detection unit 13. The image data is either a frame of a moving image or a still image. If there is a structure between the radiation source 11 and the radiation detection unit 13, the amount of radiation reaching the radiation detection unit 13 is reduced due to the structure. In this case, the signal value of each pixel of the image data varies depending on the structure of the subject M. The signal value includes pixel value, density value, etc. The reading control device 14 outputs the acquired moving or still image to the console 2. Image reading conditions include, for example, frame rate, frame interval, pixel size, image size, etc. The frame rate is the number of frames acquired per second, consistent with the pulse rate. The frame interval is the time from the start of one frame acquisition action to the start of the next frame acquisition action, and it is consistent with the pulse interval.

[0036] [Example of console 2's structure]

[0037] Console 2 is composed of computers such as personal computers and workstations. Figure 1 As shown, the console 2 includes a control unit 21, a storage unit 22, an operation unit 23, a display unit 24, and a communication unit 25. The control unit 21, storage unit 22, operation unit 23, display unit 24, and communication unit 25 are connected by wiring such as a bus 26.

[0038] The control unit 21 includes a CPU (Central Processing Unit) and RAM (Random Access Memory). Based on the operation of the operation unit 23, the CPU 21 reads the system program and various processing programs stored in the storage unit 22, expands them in the RAM, and executes various processes according to the expanded programs. The control unit 21 centrally controls the actions of each part of the control console 2, the radiation irradiation operation of the imaging device 1, and the reading operation.

[0039] Storage unit 22 is a non-volatile semiconductor memory, hard disk, or the like. Storage unit 22 stores various programs executed by control unit 21, parameters required for program-based processing, processing results, and other data. Various programs are stored in the form of readable program code. Control unit 21 executes actions according to this program code sequentially.

[0040] The operation unit 23 includes a keyboard, mouse, etc. The operation unit 23 may also be a touch panel combined with the display screen of the display unit 24. The operation unit 23 receives various instructions through user input and outputs instruction signals corresponding to the received instructions to the control unit 21.

[0041] Display unit 24 is a monitor such as an LCD (Liquid Crystal Display). Display unit 24 displays input instructions and data from operation unit 23 according to the display signal input from control unit 21.

[0042] The communication unit 25 includes a LAN adapter, modem, etc. The communication unit 25 transmits and receives signals and data with the imaging device 1, motion analysis device 3, etc., connected to the network N.

[0043] [Example of the structure of dynamic analysis device 3]

[0044] The dynamic analysis device 3 is used as a diagnostic aid to assist doctors in their diagnoses. The dynamic analysis device 3 may consist of, for example, a personal computer, a workstation, or other computer. Figure 1 As shown, the dynamic analysis device 3 includes a control unit 31, a storage unit 32, an operation unit 33, a display unit 34, and a communication unit 35. The control unit 31, storage unit 32, operation unit 33, display unit 34, and communication unit 35 are connected by wiring via a bus 36.

[0045] The control unit 31 includes a CPU, RAM, etc. Based on the operations of the operation unit 33, the CPU reads various programs P, such as the system program, stored in the storage unit 32 and expands them in the RAM, executing various processes according to the expanded programs. The control unit 31 centrally controls the operations of each part of the dynamic analysis device 3.

[0046] The storage unit 32 may include a non-volatile semiconductor memory, a hard disk, or the like. The storage unit 32 stores various programs P executed by the control unit 31, parameters required for the execution of processing based on program P, processing results, and other data. The various programs P are stored in the form of readable program code. The control unit 31 executes actions according to this program code sequentially.

[0047] The operation unit 33 includes a keyboard, mouse, etc. The operation unit 33 may also be a touch panel combined with the display screen of the display unit 24. The operation unit 33 receives various instructions through user input and outputs instruction signals corresponding to the received instructions to the control unit 31.

[0048] The display unit 34 includes a monitor such as an LCD. The display unit 34 performs various displays according to the instructions of the display signals input from the control unit 31. The communication unit 35 includes a LAN adapter, a modem, etc. The communication unit 35 transmits and receives signals and data with the control console 2, etc., connected to the network N.

[0049] The control unit 31 of the dynamic analysis device 3 functions as a first generation unit, an extraction unit, a second generation unit, and a setting unit. The functions of the first generation unit, extraction unit, second generation unit, and setting unit are realized by the processor of the control unit 31 executing the program P stored in the storage unit 32, etc. The first generation unit generates dose waveforms (waveform information) that include blood flow and respiratory changes in the region of interest of each frame image. Each frame image constitutes a dynamic image obtained through radiation-based dynamic imaging. The region of interest is called the ROI (Region of Interest). Dose waveforms are generated based on the signal values ​​of each pixel in the region of interest of each frame of the dynamic image. Figure 2 This is a diagram showing a frame image G that constitutes a dynamic image with a region of interest R defined according to this embodiment. The image was taken from the front of the chest. In this embodiment, for example, the region of interest R is defined in the lung field region of the frame image G, specifically in the area containing the pulmonary artery. This allows users such as doctors to diagnose pulmonary reflux.

[0050] The extraction unit extracts frame waveforms from the dose waveform generated by the first generation unit that contain dose variations different from blood flow variations and respiratory variations. Specifically, the extraction unit compares the reference frame waveform in the waveform information with other frame waveforms that are different from the reference frame waveform information. Hereinafter, these other frame waveforms are referred to as comparison frame waveforms. The reference frame waveform and the comparison frame waveforms are multiple frame images, consisting of the same number of frames. When the reference frame waveform and the comparison frame waveform are inconsistent, the extraction unit extracts the comparison frame waveform as a frame image containing noise such as body motion variations. Random body motion variations include, for example, variations caused by unpredictable movements of the patient, coughing, etc. The second generation unit generates information indicating that the comparison frame waveform containing body motion variations extracted by the extraction unit is unsuitable for dynamic analysis. The setting unit sets the reference frame waveform, etc., based on the type of dynamic analysis.

[0051] [Dose waveform of region of interest R in the dynamic image]

[0052] Figure 3 This is a dose waveform representing the change in signal values ​​of pixels in the region of interest R of the dynamic image involved in this embodiment. Figure 3 In the diagram, the vertical axis represents the signal value of a pixel, and the horizontal axis represents time. The dose waveform is, for example, a curve that averages the signal values ​​of each pixel in the region of interest R. The dose waveform includes at least the respiratory variations of the subject M accompanying inhalation and exhalation, and the blood flow variations accompanying the heartbeat (heartbeat).

[0053] The respiratory variations are explained. During the inspiratory period from maximal exhalation to maximal inspiration, air flows into the lung fields. The maximal expiratory position refers to the timing at which the maximum amount of air is expelled from the lung fields. The maximal inspiratory position refers to the timing at which the maximum amount of air is inhaled into the lung fields. In this case, the X-ray transmittance increases in the lung field region, and the signal value of the pixel in the region of interest R increases from the maximal expiratory position towards the maximal inspiratory position. On the other hand, during the expiratory period from maximal inspiration to maximal exhalation, air flows out of the lung fields. In this case, the X-ray transmittance decreases in the lung field region, and the signal value of the pixel in the region of interest R of the dynamic image decreases from the maximal inspiratory position towards the maximal expiratory position. Therefore, as... Figure 3 As shown, respiratory variation is a waveform that slowly shifts between the maximum expiratory and maximum inspiratory positions according to the patient's inhalation and exhalation.

[0054] Next, the changes in blood flow will be explained. When the heart is in ventricular diastole, less blood flows into the lung fields. In this case, the amount of X-rays transmitted through the pulmonary artery increases, and the signal values ​​of each pixel in the region of interest R of the dynamic image also increase. On the other hand, when the heart is in ventricular systole, a large amount of blood flows from the heart into the lung fields via the pulmonary artery. Therefore, the amount of X-rays transmitted through the lung fields decreases, and the signal values ​​of each pixel in the region of interest R of the dynamic image also decrease. Therefore, as... Figure 3 As shown, blood flow variations become waveforms that repeat the increase and decrease of signal values ​​according to the heartbeat, overlapping with the waveforms of respiratory variations.

[0055] During dynamic filming, there is a possibility of random changes in body movement caused by unpredictable movements, coughing, or poor breath-holding by the patient. For example, in Figure 3 When random body motion changes occur around time T1, the waveform around time T1 is significantly shifted compared to waveforms at the calmest respiratory rate, such as the maximum inspiratory level. When using timed waveforms showing random body motion changes for dynamic analysis, appropriate analysis results may not be obtained. Therefore, in this embodiment, timed frame waveforms showing random body motion changes are extracted from the dose waveform, and information indicating unsuitability for dynamic analysis is generated based on the extracted frame waveforms.

[0056] [Example of operation of image capturing system 100]

[0057] Figure 4 This is a flowchart illustrating an example of the operation of the dynamic analysis device 3, as described in this embodiment, in the case of extracting noise caused by body motion changes from waveform information representing dose variations in a region of interest R of a dynamic image. The control unit 31 implements this by executing the program P stored in the storage unit 32. Figure 4 The process shown includes generation steps and extraction steps, etc.

[0058] First, the operation of the imaging device 1 and the control console 2 during dynamic imaging will be explained. The control unit 21 of the control console 2 sets the radiation irradiation conditions for the radiation irradiation control device 12 and the image reading conditions for the reading control device 14. Next, the control unit 21 outputs a dynamic image imaging start instruction to the radiation irradiation control device 12 and the reading control device 14. The radiation source 11 of the imaging device 1 irradiates the subject M with radiation at pulse intervals set by the radiation irradiation control device 12. The reading control device 14 outputs the image data acquired by the radiation detection unit 13 to the control console 2.

[0059] The control unit 21 of the console 2 stores each frame of the dynamic image included in the image data sent from the imaging device 1 in the storage unit 22, establishing a correspondence between the frames and the frame numbers indicating the imaging sequence. Next, the control unit 21 displays the acquired dynamic image on the display unit 24. The radiologist or other user confirms whether the image is suitable for diagnosis. Based on the user's confirmation, the control unit 21 adds patient information and examination information to the dynamic image acquired through dynamic imaging and sends the dynamic image to the dynamic analysis device 3.

[0060] like Figure 4 As shown, the control unit 31 of the dynamic analysis device 3 acquires a dynamic image of a predetermined shooting location from the control console 2 via the communication unit 35 (step S10). For example, the shooting location is... Figure 2 The image shows the front view of the chest. The dynamic image is composed of multiple frames. The control unit 31 stores the acquired dynamic image in the storage unit 32.

[0061] The control unit 31 sets a region of interest R in the frame image of the acquired dynamic image (step S11). For example, as... Figure 2 As shown, the control unit 31 sets a region of interest R near the pulmonary artery within the lung field. The area near the pulmonary artery is a region with high blood flow and appears whiter in dynamic images. Therefore, the control unit 31 can automatically set the region of interest R as the area where more pixels with higher brightness values ​​are concentrated in the lung field region of the dynamic image. Furthermore, the setting of the region of interest R is not limited to automatic setting by the control unit 31. Users such as radiologists can also manually set the region of interest R. In this case, for example, an image of the lung field region, showing the contrast between the whiter areas due to blood flow and other areas, can be displayed on the display unit 34 for easy understanding. Users can set the region of interest R by selecting the area near the pulmonary artery in the image displayed on the display unit 34 using the operation unit 33.

[0062] The control unit 31 generates a dose waveform representing the change in signal values ​​of each pixel in the set region of interest R of all frame images (step S12). Specifically, as Figure 3 As shown, the control unit 31 generates dose waveforms in the region of interest R of each frame of the image containing dynamic images, which include respiratory variations accompanying inhalation and exhalation and blood flow variations accompanying heartbeats (heartbeats).

[0063] For the dose waveform representing the change in signal value generated, one of the first, second, and third processes is performed according to the analysis purpose before dynamic analysis processing (step S13). For example, the user can select the appropriate processing for the analysis purpose of the dynamic image from the first to third processing items displayed on the screen of the display unit 34 through the operation of the operation unit 33. Alternatively, the control unit 31 can automatically obtain the appropriate processing for the analysis purpose of the acquired dynamic image based on information such as the shooting location and the region of interest. Here, the first processing is used to extract frame waveforms containing changes corresponding to random body movements from the dose waveform. The second processing is used to extract periods less affected by periodic noise from the dose waveform. The third processing is used to extract frame images containing body movements based on a reference frame image with the region of interest R set as the entire image.

[0064] If the process branches to the first processing step in step S13, the control unit 31 performs the first processing on the acquired motion image (step S14). In this case, the control unit 31 moves to... Figure 5 Sub-processes. Figure 5 This is a flowchart illustrating an example of the operation of the control unit 31 during the first process according to this embodiment. For example... Figure 5 As shown, the control unit 31 sets a reference frame waveform in the dose waveform of the region of interest in each frame of the dynamic image (step S100). Figure 6 This is a diagram showing the dose waveform with a reference frame waveform FS set according to this embodiment. The reference frame waveform FS can be composed, for example, of multiple frame images at and around the maximum expiratory position, or multiple frame images at and around the maximum inspiratory position. This is because the frame images at the maximum expiratory and maximum inspiratory positions are least affected by respiratory variations, and appropriate dynamic analysis results can be obtained when used for dynamic analysis processing. In this embodiment, the reference frame waveform FS is set using multiple frame images at and around the maximum expiratory position. The reference frame waveform FS is set, for example, to include the peak values ​​corresponding to two heartbeats based on blood flow variations. Figure 6 In the diagram, a rectangle with a dotted line indicates the range containing the reference frame waveform FS.

[0065] The control unit 31 can also set the reference frame waveform FS according to the type of dynamic analysis to be performed. This is because, depending on the type of dynamic analysis, the content of the dynamic analysis differs, and the degree to which noise such as body movement affects each dynamic analysis varies. For example, the type of dynamic analysis can be determined based on shooting conditions such as the shooting location. Shooting conditions such as the shooting location can be set based on order information sent from RIS, etc.

[0066] The control unit 31 sets the comparison frame waveform in the dose waveform to be the comparison object of the reference frame waveform FS (step S101). Figure 7 This is a diagram showing the dose waveform, such as the comparison frame waveform Fa, as described in this embodiment. The control unit 31 can, for example, sequentially set the comparison frame waveform Fa by moving the rectangular frame of the reference frame waveform FS along the time direction of the dose waveform. Specifically, when the reference frame waveform FS is 50 to 60 frames, as an example, by moving it every 5 frames, the comparison frame waveform Fa can be set sequentially. In this case, the comparison frame waveform Fa is 55 to 65 frames. Furthermore, the number of frames moved is not limited to 5 frames; for example, it could be 1 frame. Figure 7 In the diagram, dashed rectangles indicate the range containing the comparison frame waveforms Fa, Fb, etc. Furthermore, the number of comparison frame waveforms can be set without limitation. Figure 7 The number shown. In addition, the user can also manually set the reference frame waveform FS, comparison frame waveform Fa, etc. while checking the screen on the display unit 34.

[0067] The control unit 31 sequentially determines whether the reference frame waveform FS and the comparison frame waveform Fa are consistent (step S102). Specifically, the control unit 31 compares the reference frame waveform FS with the comparison frame waveform Fa and determines the similarity between these frame waveforms. The control unit 31 may, for example, use the number of peaks or the signal value of the reference frame waveform FS to determine the similarity with the comparison frame waveform Fa. For example, when the control unit 31 uses the signal value to determine similarity, if the amplitude of the reference frame waveform FS is set to 100% and the amplitude of the comparison frame waveform is in the range of 90 to 110%, it can determine that the reference frame waveform FS and the comparison frame waveform have a high similarity. In addition, the similarity determination condition may be other than the number of peaks or the width of the signal value of the reference frame waveform FS, for example, it may use the cross-correlation function of the overall signal value waveform.

[0068] Specifically, when the comparison object with the reference frame waveform FS is the comparison frame waveform Fa, the similarity is determined as follows. Figure 7 As shown, the number of peaks in the reference frame waveform FS and the number of peaks in the comparison frame waveform Fa are both equal (2) within the rectangle. Therefore, the control unit 31 can determine that the reference frame waveform FS and the comparison frame waveform Fa have a high degree of similarity. In this case, the control unit 31 determines that the reference frame waveform FS and the comparison frame waveform Fa are consistent and proceeds to step S104.

[0069] When the comparison object with the reference frame waveform FS is the comparison frame waveform Fb, the similarity is determined as follows. Figure 7As shown, the reference frame waveform FS has two peaks within the rectangle, while the number of peaks in the comparison frame waveform Fb is unknown within the rectangle. Therefore, the control unit 31 can determine that the reference frame waveform FS and the comparison frame waveform Fb have low similarity. The control unit 31 extracts the comparison frame waveform Fb into a frame waveform that includes the patient's body movements, etc. In this case, the control unit 31 determines that the reference frame waveform FS and the comparison frame waveform Fb are inconsistent and proceeds to step S103.

[0070] The control unit 31 generates unanalyzable information (step S103) for comparison frame waveforms Fb, which are inconsistent with the reference frame waveform FS, indicating that they are not suitable for dynamic analysis processing. Specifically, processing is performed as follows when the dynamic image consists of 100 frames and noise caused by body movement is contained in frames 80 to 90. In this case, the control unit 31 generates unanalyzable information for frames 80 to 90 and appends the generated unanalyzable information to each of the 80 to 90 frames. After generating the unanalyzable information, the control unit 31 proceeds to step S104.

[0071] The control unit 31 determines whether the comparison of all set comparison frame waveforms Fa, etc., has ended (step S104). If the control unit 31 determines that the comparison of all set comparison frame waveforms Fa, etc., has not ended, it returns to step S102. The control unit 31 moves the comparison object with the reference frame waveform FS to an adjacent comparison frame waveform, etc., and repeats the above-described comparison process of the reference frame waveform FS. On the other hand, if the control unit 31 determines that the comparison with all set comparison frame waveforms Fa, etc., has ended, it enters... Figure 4 Step S17 is shown.

[0072] exist Figure 4 In step S13, if the process branches to the second processing step, the control unit 31 performs the second processing on the acquired motion image (step S15). In this case, the control unit 31 moves to... Figure 8 Sub-processes. Figure 8 This is a flowchart illustrating an example of the operation of the control unit 31 during the second processing involved in this embodiment.

[0073] The control unit 31 sets multiple frame waveforms in each respiratory cycle in the dose waveform (step S200). Figure 9This diagram illustrates the dose waveforms in this embodiment, where a first frame waveform F1, a second frame waveform F2, a third frame waveform F3, and a fourth frame waveform F4 are set within each respiratory cycle. In the first respiratory cycle C1, the control unit 31 sets the first frame waveform F1 during maximum inspiration, the second frame waveform F2 during expiration, the third frame waveform F3 during maximum expiration, and the fourth frame waveform F4 during inspiration. In the second respiratory cycle C2 and thereafter, the control unit 31 sets the first frame waveform F1, the second frame waveform F2, the third frame waveform F3, and the fourth frame waveform F4 in the same manner as in the first respiratory cycle C1.

[0074] Here, the first frame waveform F1 consists of multiple frames during the maximum inhalation period. The second frame waveform F2 consists of multiple frames located approximately midway between the maximum inhalation and maximum exhalation positions. The third frame waveform F3 consists of multiple frames during the maximum exhalation period. The fourth frame waveform F4 consists of multiple frames located approximately midway between the maximum exhalation and maximum inhalation positions. Furthermore, the number of frames can be set as follows: Figure 9 Furthermore, the setting position of the frame waveform is not limited to... Figure 9 It can be set at any position (period) of the dose waveform.

[0075] The control unit 31 compares the frame waveforms that are in the same period according to each respiratory cycle. Based on the comparison results, the control unit 31 determines whether any one of the multiple frame waveforms in each respiratory cycle is abnormal (step S201). Specifically, as follows... Figure 9 As shown, the control unit 31 compares the first frame waveform F1, the second frame waveform F2, the third frame waveform F3, and the fourth frame waveform F4, which are set according to every n respiratory cycles. n is a positive integer. The control unit 31 can also determine the similarity between the waveforms based on the number of peaks in each frame waveform, the width of the signal value of the waveform, etc.

[0076] If the first frame waveform F1 of the first respiratory cycle C1 does not contain a frame waveform with low similarity to the corresponding frame waveforms of other respiratory cycles, the control unit 31 determines that there is no periodic noise in the first respiratory cycle C1. The control unit 31 performs the same processing as during the first respiratory cycle for other respiratory cycles besides the first respiratory cycle C1. If there is no periodic noise in all respiratory cycles, the control unit 31 determines that there are no abnormalities in all respiratory cycles. In this case, the control unit 31 enters... Figure 4 Step S17.

[0077] On the other hand, if the first frame waveform F1 of the first respiratory cycle C1 contains a frame waveform with low similarity to the corresponding frame waveforms of other respiratory cycles, the control unit 31 determines that periodic noise is present in the first respiratory cycle C1. The control unit 31 performs the same processing as during the first respiratory cycle for other respiratory cycles besides the first respiratory cycle C1. If periodic noise is present in at least one or more respiratory cycles, the control unit 31 determines that any one of the respiratory cycles is abnormal. In this case, the control unit 31 extracts the respiratory cycle containing periodic noise and proceeds to step S202.

[0078] For the extracted frame waveforms of abnormal respiratory cycles, the control unit 31 generates unanalyzable information indicating that it is unsuitable for dynamic analysis processing (step S202). For example, the control unit 31 may also extract periodic respiratory cycles with less noise by appending unanalyzable information to all frame waveforms of the determined respiratory cycles. After generating the unanalyzable information, the control unit 31 proceeds to... Figure 4 Step S17.

[0079] exist Figure 4 In step S13, if the process branches to the third processing, the control unit 31 performs the third processing on the acquired dynamic image (step S16). Specifically, the control unit 31 determines the frame image as a reference frame image based on the signal value waveform of the overall image, where the region of interest R of each frame is set as the region of interest R. The control unit 31 calculates the similarity to the reference frame image in each frame of a specific number of frames that are intended to be used in the dynamic analysis. The similarity determination can also use signal values, etc., as described above. Based on the similarity comparison result, the control unit 31 determines the frame image with low similarity that exceeds a threshold as an abnormal frame image containing noise caused by body movement, and extracts the frame image with low similarity. The control unit 31 can either discard the extracted frame image or add unanalyzable information to the extracted frame image as described above.

[0080] The control unit 31 uses the generated dose waveform to perform dynamic analysis processing according to the purpose (step S17). After performing the first and second processing, the control unit 31 performs dynamic analysis processing on frame images in which no unanalyzable information is attached. In other words, the control unit 31 performs dynamic analysis processing on frame images that do not contain noise caused by the patient's body movements, etc.

[0081] The control unit 31 displays the generated dose waveform and dynamic analysis results on the screen of the display unit 34 (step S18). For example, if the control unit 31 has performed the first and second processes, it displays the results of the dynamic analysis processing performed on the frame image without attached unanalyzable information on the screen of the display unit 34. At this time, the control unit 31 may also display a message indicating that the frame image with attached unanalyzable information is not used for dynamic analysis processing on the screen of the display unit 34.

[0082] According to this embodiment, through the implementation of the first process, the dynamic analysis device 3 compares the reference frame waveform and the comparison frame waveform in the dose waveform, and extracts the comparison frame waveform that is inconsistent with the reference frame waveform. Therefore, it is possible to extract frame waveforms containing noise caused by random body movement variations of the patient from the respiratory cycle of the dose waveform. Furthermore, the dynamic analysis device 3 uses frame images at the time when respiratory changes are calm, i.e., during maximal inspiration or maximal expiration, as the reference frame waveform. Therefore, since it is possible to extract only frame images of the portion with minimal respiratory changes from the dose waveform, a highly accurate dynamic image that does not contain random body movement variations can be obtained. Thus, a suitable dynamic image can be used to perform the prescribed dynamic analysis, and therefore, accurate analysis results can be obtained.

[0083] According to this embodiment, through the implementation of the second process, the dynamic analysis device 3 can determine that if multiple frame waveforms set according to each respiratory cycle contain frame waveforms with low similarity, the respiratory cycle contains periodic noise such as involuntary movements or arrhythmia that indicate neurological symptoms. Furthermore, the dynamic analysis device 3 adds unanalyzable information to the frame waveforms of respiratory cycles containing periodic noise, thus obtaining a highly accurate dynamic image. Therefore, a suitable dynamic image can be used to perform the prescribed dynamic analysis, resulting in accurate analysis results.

[0084] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings, but the technical scope of this disclosure is not limited to these examples. Furthermore, various modifications and improved technical solutions implemented by those skilled in the art within the scope of the technical concept described in the claims naturally fall within the technical scope of this disclosure.

[0085] For example, in the above embodiment, the dynamic analysis device 3 performs noise extraction processing on the dynamic image, including random body movement variations of the patient, but it is not limited to this. For example, the console 2 can also function as a dynamic image processing device to perform noise extraction processing on the dynamic image. Alternatively, an information processing device such as a client terminal can also function as a dynamic image processing device to perform noise extraction processing on the dynamic image.

[0086] Furthermore, in the above embodiment, noise extraction processing of the moving image was performed using the operation unit 33 and display unit 34 of the motion analysis device 3, but it is not limited to this. For example, the operation unit and display unit of an information processing device such as another client terminal connected to the network N may also be used. In this case, the motion analysis device 3 may also be structured without the operation unit 33 and display unit 34.

Claims

1. A dynamic image processing apparatus, wherein, have: The first generation unit generates waveform information containing blood flow and respiratory changes in a defined area of ​​each frame image, and each frame image constitutes a dynamic image obtained by dynamic imaging based on radiation. as well as The extraction unit extracts waveform information from the waveform information generated by the first generation unit that includes dose variations that are different from the blood flow variations and the respiratory variations.

2. The dynamic image processing apparatus according to claim 1, wherein, The system includes a second generation unit that generates information representing a dynamic image that is not suitable for dynamic analysis based on the waveform information extracted by the extraction unit.

3. The dynamic image processing apparatus according to claim 1, wherein, If the first waveform information and the second waveform information are inconsistent when compared with the first waveform information which serves as a reference, the extraction unit extracts the second waveform information.

4. The dynamic image processing apparatus according to claim 3, wherein, The first waveform information includes multiple frame images during the maximum respiratory cycle based on the respiratory variation or multiple frame images during the maximum inspiration period.

5. The dynamic image processing apparatus according to claim 3, wherein, The device includes a setting unit that sets the first waveform information based on the type of dynamic analysis.

6. The dynamic image processing apparatus according to claim 3, wherein, When the second waveform information includes changes in the patient's body movement, the extraction unit extracts the second waveform information.

7. The dynamic image processing apparatus according to claim 1, wherein, The first generation unit generates the waveform information based on the signal values ​​of each pixel in the specified region of each frame of the dynamic image.

8. A dynamic image processing method, wherein, have: In the first generation step, waveform information containing blood flow changes and respiratory changes in a specified area of ​​each frame image is generated, and each frame image constitutes a dynamic image obtained by dynamic imaging based on radiation. as well as The extraction step involves extracting waveform information from the generated waveform information that includes dose variations that differ from the blood flow variations and the respiratory variations.

9. The dynamic image processing method according to claim 8, wherein, It has a second generation step, in which information representing a dynamic image that is not suitable for dynamic analysis is generated based on the waveform information extracted by the extraction step.

10. The dynamic image processing method according to claim 8, wherein, In the extraction step, if the first waveform information is inconsistent with the second waveform information when comparing the first waveform information which serves as a reference with the second waveform information which is different from the first waveform information, the second waveform information is extracted.

11. The dynamic image processing method according to claim 10, wherein, The first waveform information includes multiple frame images during the maximum respiratory cycle based on the respiratory variation or multiple frame images during the maximum inspiration period.

12. The dynamic image processing method according to claim 10, wherein, It includes a setting step in which the first waveform information is set based on the type of dynamic analysis.

13. The dynamic image processing method according to claim 10, wherein, In the extraction step, if the second waveform information contains changes in the patient's body movement, the second waveform information is extracted.

14. The dynamic image processing method according to claim 8, wherein, In the first generation step, the waveform information is generated based on the signal values ​​of each pixel in the specified region of each frame of the dynamic image.

15. A computer program product, wherein, Used to enable the computer to function as: The first generation unit generates waveform information containing blood flow and respiratory changes in a defined area of ​​each frame image, and each frame image constitutes a dynamic image obtained by dynamic imaging based on radiation. as well as The extraction unit extracts waveform information from the waveform information generated by the first generation unit that includes dose variations that are different from the blood flow variations and the respiratory variations.

16. The computer program product according to claim 15, wherein, The computer is used as a second generation unit, which generates information representing a dynamic image that is not suitable for dynamic analysis based on the waveform information extracted by the extraction unit.

17. The computer program product according to claim 15, wherein, If the first waveform information and the second waveform information are inconsistent when compared with the first waveform information which serves as a reference, the extraction unit extracts the second waveform information.

18. The computer program product according to claim 17, wherein, The first waveform information includes multiple frame images during the maximum respiratory cycle based on the respiratory variation or multiple frame images during the maximum inspiration period.

19. The computer program product according to claim 17, wherein, The computer is used as a setting unit, which sets the first waveform information based on the type of dynamic analysis.

20. The computer program product according to claim 17, wherein, When the second waveform information includes changes in the patient's body movement, the extraction unit extracts the second waveform information.

21. The computer program product according to claim 15, wherein, The first generation unit generates the waveform information based on the signal values ​​of each pixel in the specified region of each frame of the dynamic image.

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