JPWO2011093221A1 - Dynamic image processing system and program - Google Patents

Abstract

According to the diagnostic console 3 according to the present invention, the control unit 31 controls the control unit 31 for one respiratory cycle started from the time of maximum expiration or maximum inspiration from a series of frame images indicating the dynamics of the chest. And the expiration time and the inspiration time of the subject are calculated based on the number of extracted frame images for one respiratory cycle and the frame rate at the time of capturing these frame images. Based on whether the time and the inspiratory time are inconsistent, it is determined whether or not the subject's lung ventilation function is abnormal, and diagnostic support information indicating the determination result is displayed on the display unit 34. This makes it possible to provide the doctor with diagnosis support information based on the patient's own breathing and inhalation movements with a small burden on the patient.

Description

  The present invention relates to a dynamic image processing system and a program.

  In contrast to still image photography and diagnosis by chest radiation using conventional film / screen or photostimulable phosphor plate, a dynamic image of the chest is taken using a semiconductor image sensor such as FPD (flat panel detector), Attempts have been made to apply it to diagnosis. Specifically, by utilizing the responsiveness of reading / erasing of image data of the semiconductor image sensor, pulsed radiation is continuously irradiated from the radiation source in accordance with the reading / erasing timing of the semiconductor image sensor. Take multiple shots per second to capture the dynamics of the chest. By sequentially displaying a series of a plurality of images acquired by photographing, a doctor can recognize a series of movements of the chest associated with respiratory motion or the like.

  Various techniques for analyzing dynamic images and providing diagnosis support information to doctors have also been proposed. For example, Patent Document 1 discloses that a plurality of images are integrated by holding maximum values (minimum values, average values, intermediate values) in corresponding pixels of a plurality of images constituting a dynamic image. And a difference image between each image and a result image composed of pixels indicating the maximum absolute value (minimum absolute value, average value, intermediate value) in the corresponding pixel group of the generated difference image. Generate and compare each pixel value of the result image with the variation value known from normal medical knowledge or experience, and mark and display an area showing an abnormality such as a very large (small) difference value The technology is described.

JP 2004-31434 A

  However, in Patent Document 1, an abnormality cannot be determined unless a variation value (threshold value) known from medical knowledge or experience is acquired in advance. In addition, there are individual differences in respiratory movement, and even if the movement of the individual is normal, there is a possibility that it is determined to be abnormal by setting a threshold value.

  In addition, when the lung ventilation function is normal, the chest movements during expiration and inspiration should be almost symmetrical with respect to the conversion point, and abnormal movement is possible if the movement is different from symmetry. There is sex. However, in Patent Document 1, such an abnormal movement cannot be detected.

  In addition, there are lung function tests that do not use dynamic images such as lung scintigraphy and spiro test, but the inspection time is longer than that of dynamic images and the patient is forced to take many forced breaths. large.

  An object of the present invention is to provide diagnosis support information based on movements of a patient during exhalation and inspiration with a small burden on the patient.

In order to solve the above-described problem, a dynamic image processing system according to claim 1 is provided.
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion When,
Calculation means for calculating the expiration time and the inspiration time of the subject based on the number of extracted frame images for one respiratory cycle and the frame rate at the time of capturing these frame images;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the expiration time and the inspiration time calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
Is provided.

The dynamic image processing system of the invention according to claim 2
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion When,
The extracted frame image of the start of one breathing cycle is a first frame image, the frame image of a conversion point between expiration and inspiration is a second frame image, and the final frame image of the one breathing cycle is a third frame image. And operating means for designating one frame image from among the frame images existing between the first frame image and the second frame image;
An approximate frame image that most closely approximates the designated frame image is extracted from frames existing between the second frame image and the third frame image, and the second frame is extracted from the designated frame image. Calculating means for calculating a time to an image and a time from the second frame image to the approximate frame image based on a frame rate at the time of shooting;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the two times calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
Is provided.

The invention according to claim 3 is the invention according to claim 1 or 2,
The calculation means calculates one breathing cycle time of the subject based on the number of frame images for one extracted breathing cycle and the frame rate at the time of capturing these frame images;
The determination unit further determines whether or not the lung ventilation function of the subject is abnormal based on whether or not the calculated one respiratory cycle time is equal to or less than a predetermined threshold value.

The invention according to claim 4 is the invention according to any one of claims 1 to 3,
The plurality of frame images are X-ray images;
The extraction unit calculates an area of the direct X-ray irradiation region in each of the plurality of frame images, and specifies a frame image having a maximum area of the calculated direct X-ray irradiation region as a frame image at the time of maximum expiration. The frame image in which the calculated area of the direct X-ray irradiation region is minimal is specified as the frame image at the time of maximum inspiration.

The program of the invention described in claim 5 is:
Computer
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion ,
A calculating means for calculating an expiration time and an inspiration time of the subject based on the number of extracted frame images for one respiratory cycle and a frame rate at the time of capturing these frame images;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the expiration time and the inspiration time calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
To function as.

The program of the invention described in claim 6 is:
Computer
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion ,
The extracted frame image of the start of one breathing cycle is a first frame image, the frame image of a conversion point between expiration and inspiration is a second frame image, and the final frame image of the one breathing cycle is a third frame image. And operating means for designating one frame image from among the frame images existing between the first frame image and the second frame image,
An approximate frame image that most closely approximates the designated frame image is extracted from frames existing between the second frame image and the third frame image, and the second frame is extracted from the designated frame image. Calculating means for calculating the time to the image and the time from the second frame image to the approximate frame image based on the frame rate at the time of shooting;
Determining means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the two times calculated by the calculating means are mismatched;
Display means for displaying diagnosis support information indicating the determination result;
To function as.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide a doctor with the diagnostic assistance information based on the movement at the time of exhalation and inhalation of a patient's own with little burden for a patient.

It is a figure which shows the whole structure of the dynamic image processing system in embodiment of this invention. It is a figure which shows the example of data storage of the determination table memorize | stored in the memory | storage part of the diagnostic console of FIG. 3 is a flowchart illustrating a shooting control process executed by a control unit of the shooting console of FIG. 1. It is a flowchart which shows the image analysis process A performed by the control part of the diagnostic console of FIG. It is a figure which shows the frame image of the several time phase T (T = t0-t6) image | photographed in one respiration cycle. (A) is a figure which shows the relationship between the inhalation time and expiration time which were obtained from the dynamic image of a subject with normal lung ventilation function, (b) is the relationship between the inhalation time and expiration time when abnormal division = 1 (C) is a diagram showing the relationship between the inspiratory time and the expiration time when the abnormal category = 2, and (d) is the relationship between the inspiratory time and the expiration time when the abnormal category = 1,2. FIG. It is a flowchart which shows the image-analysis process B performed by the control part of the diagnostic console of FIG. (A) is the figure which shows the relationship between the time between the designated frame obtained from the dynamic image of the subject with normal lung ventilation function and the maximum inspiration, the time between the maximum inspiration and the approximate frame, (b) FIG. 4C is a diagram showing the relationship between the time between the designated frame and the maximum intake when the abnormal category = 1 and the time between the maximum intake and the approximate frame, and FIG. 5C shows the designation when the abnormal category = 2. The figure which shows the relationship between the time between a flame | frame and the maximum intake, the time between the maximum intake and an approximate frame, (d) is between the designated frame and the maximum intake when the abnormal classification = 1, 2 It is a figure which shows the relationship of time between time and the largest intake, and an approximate frame.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

<First Embodiment>
[Configuration of Dynamic Image Processing System 100]
First, the configuration will be described.

  FIG. 1 shows the overall configuration of a dynamic image processing system 100 in the present embodiment.

  As shown in FIG. 1, in the dynamic image processing system 100, an imaging device 1 and an imaging console 2 are connected by a communication cable or the like, and the imaging console 2 and the diagnostic console 3 are connected to a LAN (Local Area Network). Etc., and connected via a communication network NT. Each device constituting the dynamic image processing system 100 conforms to the DICOM (Digital Image and Communications in Medicine) standard, and communication between the devices is performed according to DICOM.

[Configuration of the photographing apparatus 1]
The imaging apparatus 1 is an apparatus that images the dynamics of the chest with periodicity (cycle), such as pulmonary expansion and contraction morphological changes, heart pulsation, and the like accompanying respiratory motion. Dynamic imaging is performed by continuously irradiating a human chest with radiation such as X-rays to acquire a plurality of images (that is, continuous imaging). A series of images obtained by this continuous shooting is called a dynamic image. Each of the plurality of images constituting the dynamic image is called a frame image.

  As shown in FIG. 1, the imaging apparatus 1 includes a radiation source 11, a radiation irradiation control device 12, a radiation detection unit 13, a reading control device 14, a cycle detection sensor 15, a cycle detection device 16, and the like.

  The radiation source 11 irradiates the subject M with radiation (X-rays) under the control of the radiation irradiation control device 12.

  The radiation irradiation control device 12 is connected to the imaging console 2 and controls the radiation source 11 based on the radiation irradiation conditions input from the imaging console 2 to perform radiation imaging. The radiation irradiation conditions input from the imaging console 2 are, for example, pulse rate, pulse width, pulse interval, imaging start / end timing, X-ray tube current value, X-ray tube voltage value, filter type during continuous irradiation. Etc. The pulse rate is the number of times of radiation irradiation per second, and matches the frame rate described later. The pulse width is a radiation irradiation time per one irradiation. The pulse interval is the time from the start of one radiation irradiation to the start of the next radiation irradiation in continuous imaging, and coincides with a frame interval described later.

  The radiation detection unit 13 is configured by a semiconductor image sensor such as an FPD. The FPD has, for example, a glass substrate or the like, detects radiation that has been irradiated from the radiation source 11 and transmitted through at least the subject M at a predetermined position on the substrate according to its intensity, and detects the detected radiation as an electrical signal. A plurality of pixels to be converted and stored are arranged in a matrix. Each pixel includes a switching unit such as a TFT (Thin Film Transistor).

  The reading control device 14 is connected to the imaging console 2. The reading control device 14 controls the switching unit of each pixel of the radiation detection unit 13 based on the image reading condition input from the imaging console 2 to switch the reading of the electrical signal accumulated in each pixel. Then, the image data is acquired by reading the electrical signal accumulated in the radiation detection unit 13. This image data is a frame image. Then, the reading control device 14 outputs the acquired frame image to the photographing console 2. The image reading conditions are, for example, a frame rate, a frame interval, a pixel size, an image size (matrix size), and the like. The frame rate is the number of frame images acquired per second and matches the pulse rate. The frame interval is the time from the start of one frame image acquisition operation to the start of the next frame image acquisition operation in continuous shooting, and coincides with the pulse interval.

  Here, the radiation irradiation control device 12 and the reading control device 14 are connected to each other and exchange synchronization signals with each other to perform a radiation irradiation operation and a series of images such as reset-accumulation-data reading-reset-dark image reading-reset. The reading operation is synchronized.

  The cycle detection sensor 15 detects the respiratory motion state of the subject M and outputs detection information to the cycle detection device 16. As the cycle detection sensor 15, for example, a respiration monitor belt, a CCD (Charge Coupled Device) camera, an optical camera, a spirometer, or the like can be applied.

  Based on the detection information input by the cycle detection sensor 15, the cycle detection device 16 determines the number of respiratory cycles and the state during one cycle of the current respiratory motion (for example, inspiration, inspiration to expiration conversion point, The state of the conversion point of exhalation and exhalation to inspiration is detected, and the detection result (cycle information) is output to the control unit 21 of the imaging console 2. For example, the cycle detection device 16 sets 1 timing when detection information indicating that the state of the lung is a conversion point from inspiration to expiration is input by the cycle detection sensor 15 (respiration monitor belt, CCD camera, optical camera, etc.). The cycle point is recognized as one cycle until the next timing when this state is detected.

[Configuration of the shooting console 2]
The imaging console 2 outputs radiation irradiation conditions and image reading conditions to the imaging apparatus 1 to control radiation imaging and radiographic image reading operations by the imaging apparatus 1, and also captures dynamic images acquired by the imaging apparatus 1. Displayed for confirmation of whether the image is suitable for confirmation of positioning or diagnosis.

  As shown in FIG. 1, the imaging console 2 includes a control unit 21, a storage unit 22, an operation unit 23, a display unit 24, and a communication unit 25, and each unit is connected by a bus 26.

  The control unit 21 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like. The CPU of the control unit 21 reads the system program and various processing programs stored in the storage unit 22 in accordance with the operation of the operation unit 23, expands them in the RAM, and performs shooting control processing described later according to the expanded programs. Various processes including the beginning are executed to centrally control the operation of each part of the imaging console 2 and the radiation irradiation operation and the reading operation of the imaging apparatus 1.

  The storage unit 22 is configured by a nonvolatile semiconductor memory, a hard disk, or the like. The storage unit 22 stores various programs executed by the control unit 21 and data such as parameters necessary for execution of processing by the programs or processing results. For example, the storage unit 22 stores a shooting control processing program for executing the shooting control process shown in FIG. The storage unit 22 stores radiation irradiation conditions and image reading conditions. Various programs are stored in the form of readable program code, and the control unit 21 sequentially executes operations according to the program code.

  The operation unit 23 includes a keyboard having a cursor key, numeric input keys, various function keys, and the like, and a pointing device such as a mouse. The control unit 23 controls an instruction signal input by key operation or mouse operation on the keyboard. To 21. In addition, the operation unit 23 may include a touch panel on the display screen of the display unit 24. In this case, the operation unit 23 outputs an instruction signal input via the touch panel to the control unit 21.

  The display unit 24 is configured by a monitor such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube), and displays an input instruction, data, or the like from the operation unit 23 in accordance with an instruction of a display signal input from the control unit 21. To do.

  The communication unit 25 includes a LAN adapter, a modem, a TA (Terminal Adapter), and the like, and controls data transmission / reception with each device connected to the communication network NT.

[Configuration of diagnostic console 3]
The diagnostic console 3 is a dynamic image processing device that acquires a dynamic image from the imaging console 2, displays the acquired dynamic image, and makes a diagnostic interpretation by a doctor.

  As shown in FIG. 1, the diagnostic console 3 includes a control unit 31, a storage unit 32, an operation unit 33, a display unit 34, and a communication unit 35, and each unit is connected by a bus 36.

  The control unit 31 includes a CPU, a RAM, and the like. The CPU of the control unit 31 reads out the system program and various processing programs stored in the storage unit 32 in accordance with the operation of the operation unit 33 and expands them in the RAM, and performs image analysis described later according to the expanded programs. Various processes including the process A are executed to centrally control the operation of each part of the diagnostic console 3.

  The storage unit 32 is configured by a nonvolatile semiconductor memory, a hard disk, or the like. The storage unit 32 stores data such as parameters necessary for execution of processing or data such as processing results by various programs including the image analysis processing A program for executing the image analysis processing A by the control unit 31. These various programs are stored in the form of readable program codes, and the control unit 31 sequentially executes operations according to the program codes.

  The storage unit 32 stores a determination table 321 shown in FIG. The determination table 321 is a table that is referred to when determining a disease name corresponding to an abnormality category in image analysis processing A described later. As shown in FIG. 2, the determination table 321 stores a combination of abnormal categories = 1, 2 and a disease name that can be considered based on the combination. In FIG. 2, “◯” indicates a case in which it is determined that there is an abnormality corresponding to the abnormality classification indicated in the item, and “−” indicates that there is no abnormality corresponding to the abnormality classification indicated in the item (normal). Indicates the case. In addition, a calculation formula under “◯” indicates that it corresponds to a corresponding disease name when the calculation formula applies.

  The operation unit 33 includes a keyboard having cursor keys, numeric input keys, various function keys, and the like, and a pointing device such as a mouse. The control unit 33 controls an instruction signal input by key operation or mouse operation on the keyboard. To 31. The operation unit 33 may include a touch panel on the display screen of the display unit 34, and in this case, an instruction signal input via the touch panel is output to the control unit 31.

  The display unit 34 as a display unit is configured by a monitor such as an LCD or a CRT, and displays an input instruction, data, or the like from the operation unit 33 in accordance with an instruction of a display signal input from the control unit 31.

  The communication unit 35 includes a LAN adapter, a modem, a TA, and the like, and controls data transmission / reception with each device connected to the communication network NT.

[Operation of Dynamic Image Processing System 100]
Next, the operation in the dynamic image processing system 100 will be described.

(Operation of the photographing apparatus 1 and the photographing console 2)
First, the photographing operation by the photographing apparatus 1 and the photographing console 2 will be described.

  FIG. 3 shows photographing control processing executed in the control unit 21 of the photographing console 2. The photographing control process is executed in cooperation with the photographing control processing program stored in the control unit 21 and the storage unit 22.

  First, the operation unit 23 of the imaging console 2 is operated by the imaging engineer, and patient information (patient name, height, weight, age, sex, etc.) of the imaging target (subject M) is input (step S1).

  Next, the radiation irradiation conditions are read from the storage unit 22 and set in the radiation irradiation control device 12, and the image reading conditions are read from the storage unit 22 and set in the reading control device 14 (step S2). The frame rate (pulse rate) is preferably 5 frames / second or more in consideration of the natural breathing cycle of the human body.

  Next, the radiation irradiation instruction by the operation of the operation unit 23 is waited. When the radiation irradiation instruction is input by the operation unit 23 (step S3; YES), the cycle detection start instruction is output to the cycle detection device 16, and the cycle The detection of the respiratory motion of the subject M by the detection sensor 15 and the cycle detection device 16 is started (step S4). When the cycle detection device 16 detects a predetermined state (for example, a conversion point from inspiration to expiration), an imaging start instruction is output to the radiation irradiation control device 12 and the reading control device 14, and dynamic imaging starts. (Step S5). That is, radiation is emitted from the radiation source 11 at a pulse interval set in the radiation irradiation control device 12, and a frame image is acquired by the radiation detection unit 13. When the cycle detecting device 16 detects a predetermined number of dynamic cycles, the control unit 21 outputs an instruction to end imaging to the radiation irradiation control device 12 and the reading control device 14, and the imaging operation is stopped.

  Frame images obtained by shooting are sequentially input to the shooting console 2, stored in the storage unit 22 in association with numbers indicating the shooting order (step S6), and displayed on the display unit 24 (step S7). . The imaging engineer confirms the positioning and the like based on the displayed dynamic image, and determines whether an image suitable for diagnosis is acquired by imaging (imaging OK) or re-imaging is necessary (imaging NG). Then, the operation unit 23 is operated to input a determination result.

  When a determination result indicating that the shooting is OK is input by a predetermined operation of the operation unit 23 (step S8; YES), an identification ID for identifying the dynamic image or each of a series of frame images acquired by the dynamic shooting is displayed. Information such as patient information, examination target part, radiation irradiation condition, image reading condition, imaging order number, cycle information, etc. are attached (for example, written in the header area of image data in DICOM format) To the diagnostic console 3 (step S9). Then, this process ends. On the other hand, when a determination result indicating photographing NG is input by a predetermined operation of the operation unit 23 (step S8; NO), a series of frame images stored in the storage unit 22 is deleted (step S10), and this processing is performed. finish.

(Operation of diagnostic console 3)
Next, the operation in the diagnostic console 3 will be described.

  In the diagnostic console 3, when a series of frame images of the dynamic image is received from the imaging console 2 via the communication unit 35, the control unit 31 and the image analysis processing A program stored in the storage unit 32 The image analysis process A shown in FIG. 4 is executed in cooperation. By executing the processing, an extraction unit, a calculation unit, and a determination unit are realized.

  In the image analysis process A, first, a frame image at the time of the maximum expiration and a frame image at the time of the maximum inspiration are extracted from a series of frame images of the dynamic image (step S11).

  FIG. 5 shows frame images of a plurality of time phases T (T = t0 to t6) taken in one respiratory cycle. As shown in FIG. 5, the respiratory cycle is composed of inspiration and expiration. Inhalation causes air to be taken into the lungs by lowering the diaphragm and expanding the rib cage, and the lung field region becomes larger as shown in FIG. At the time of the maximum inspiration, the lung field region is the largest and the diaphragm position is the lowest. Further, the rib cage is in a state where it expands most horizontally and vertically. In exhalation, air is discharged from the lungs when the diaphragm rises and the expanded rib cage returns to its original shape, and the lung field area becomes smaller as shown in FIG. At maximum exhalation, the lung field area is the smallest and the diaphragm is at the highest position. Also, the rib cage is minimal.

  Therefore, in step S11, based on the area of the lung field region in the series of frame images, the frame image at the time of maximum expiration and the frame image at the time of maximum inspiration are extracted. Specifically, first, lung field regions are extracted from each frame image. Next, the area of the lung field area in each frame image is calculated, and when arranged in time series, the frame image corresponding to the conversion point (the area is maximal) where the area changes from increasing to decreasing is the frame image and area of the maximum inspiration A frame image corresponding to a conversion point (area is minimal) that changes from decreasing to increasing is extracted as a frame image of maximum exhalation.

  Extraction of a lung field region can be performed by the following method.

  Since the lung field region has a large amount of transmission of radiation (X-rays), the pixel signal value (density value; hereinafter referred to as signal value) is higher than the surrounding region. Therefore, first, in each frame image, a density histogram is created from the signal value of each pixel, and a threshold value is obtained by a discriminant analysis method or the like. Next, a region having a signal higher than the obtained threshold is extracted as a lung field region candidate. Next, edge detection is performed near the boundary of the candidate area, and a point where the edge is maximum in a small area near the boundary is extracted along the boundary. Then, the extracted edge point is approximated by a polynomial function to obtain a boundary line of the lung field region.

  The area of the lung field region can be calculated by counting the number of pixels in the extracted lung field region.

  In step S11, the position of the diaphragm of each frame image may be obtained, and based on this, the frame image at the time of maximum expiration and the frame image at the time of maximum inspiration may be extracted.

  In addition, based on the area of the direct X-ray irradiation area of each frame image (the unexposed area irradiated with X-rays directly without passing through the subject M), the frame image at the maximum expiration and the frame image at the maximum inspiration are extracted. It is good to do.

  As described above, since the thorax is expanded to the left and right and up and down at the maximum inspiration, the area occupied by the subject area is the largest in the image. Therefore, since the area of the direct X-ray irradiation region is minimal at the maximum inspiration, a frame image having a minimum area of the direct X-ray irradiation region can be extracted as the frame image of the maximum inspiration.

  On the other hand, since the rib cage is in the smallest state at the time of the maximum expiration, the area occupied by the subject area in the image is the smallest. Therefore, since the area of the direct X-ray irradiation region is maximized at the time of maximum expiration, a frame image having the maximum area of the direct X-ray irradiation region can be extracted as a frame image of maximum inspiration.

  Here, the direct X-ray irradiation region can be obtained by binarizing the signal value of each pixel of the frame image with a predetermined threshold and extracting the region where the signal value is higher than the threshold. In capturing a dynamic image, since a plurality of images are captured at a time, it is necessary to reduce the X-ray exposure amount for capturing one frame image as compared with a still image in order to reduce the X-ray exposure amount of the subject M as much as possible. There is. Therefore, each frame image has a larger amount of noise than a still image, and the lung field region may not be extracted well. However, since the direct X-ray irradiation region shows a signal value much higher than that of the subject region, even if there is noise, the extraction can be easily performed with high accuracy. Also, for example, in the case where the movement of the diaphragm is reduced and the respiration is covered by the expansion of the rib cage as in a patient with severe restrictive lung disease, the change in the area of the entire subject region due to the respiration is large ( That is, the change in the area of the direct X-ray irradiation region is large), which is particularly effective.

  Next, the number of frame images for one respiratory cycle is extracted (step S12).

  For example, a sequence of frame images from the maximum expiratory frame image of any respiratory cycle to the next maximum expiratory frame image, or a sequence of frame images of the maximum inspiratory frame of any respiratory cycle to the next maximum inspiratory frame image Are extracted as frame images for one respiratory cycle. In the present embodiment, a series of frame images from the maximum expiratory frame image of the first respiratory cycle to the next maximum expiratory frame image are extracted as frame images for one respiratory cycle.

  Next, based on the extracted number of frame images for one respiratory cycle and the frame rate at the time of imaging, inspiration time, expiration time, and one respiratory cycle time are calculated (step S13).

  For example, the intake time can be obtained by the following equation 1.

Inspiration time = (1 ÷ frame rate) × (number of frame images from maximum expiratory frame image to maximum inspiratory frame image−1) Equation 1
The expiration time can be obtained by the following equation 2.

Expiration time = (1 ÷ frame rate) × (number of frame images from maximum inspiration frame image to maximum expiration frame image−1) Equation 2
One respiratory cycle time can be obtained by the following Equation 3.

1 breathing cycle time = inspiratory time + expiratory time Equation 3
Next, it is determined whether or not the inspiratory time and the expiratory time substantially coincide (whether or not they coincide) (step S14). For example, if the time difference between the inspiratory time and the expiratory time is within one frame interval time (error range), it is determined that they are substantially coincident. If it is determined that the inspiration time and the expiration time are substantially the same (step S14; YES), the process proceeds to step S16. If it is determined that the inspiratory time and the expiratory time do not match (step S14; NO), it is determined that the lung ventilation function of the subject M is abnormal, the abnormal classification (here, 1), the inspiratory time, and the expiratory time. The time is stored in a predetermined area of the RAM of the control unit 31 (step S15), and the process proceeds to step S16.

  Next, it is determined whether or not one respiratory cycle time is equal to or less than a predetermined threshold value (step S16). The threshold value in step S16 is a value obtained experimentally and empirically as the lower limit of a normal one respiratory cycle time. If it is determined that one respiratory cycle time is not less than or equal to the threshold value (step S16; NO), the process proceeds to step S18. If it is determined that one respiratory cycle time is equal to or less than the threshold (step S16; YES), it is determined that the lung ventilation function of the subject M is abnormal, and an abnormal classification (here, 2), one respiratory cycle time Is stored in a predetermined area of the RAM of the control unit 31 (step S17), and the process proceeds to step S18.

  In step S18, diagnosis support information is displayed on the display unit 34 based on the data stored in the predetermined area of the RAM (step S18), and the image analysis process A ends.

  For example, when no data is stored in a predetermined area of the RAM, “normal” characters and the like are displayed on the display unit 34 as diagnosis support information.

  When abnormality classification = 1 is stored in a predetermined area of the RAM, for example, “abnormal”, expiration time, inspiration time, and the like are displayed as diagnosis support information. In addition, the determination table 321 is referred to, and when there is a disease name corresponding to the current abnormality category, the disease name is displayed. The storage unit 32 stores a relationship between the difference between the expiration time and the inspiration time and the severity, and stores the severity corresponding to the difference between the expiration time and the inspiration time calculated this time. It is good also as displaying instead of these with time and expiration time.

  When abnormality classification = 2 is stored in a predetermined area of the RAM, for example, “abnormal” is displayed as diagnosis support information, and one respiratory cycle time or the like is displayed. In addition, when the determination table 321 is referred to and there is a disease name corresponding to the current abnormality category, the disease name is displayed. The storage unit 32 stores the relationship between the one respiratory cycle time and the severity in association with each other, and the severity corresponding to the one respiratory cycle time calculated this time together with the current one respiratory cycle time or this It is good also as displaying instead of.

  When abnormal divisions = 1 and 2 are stored in a predetermined area of the RAM, for example, “abnormal”, inhalation time, expiration time, respiration cycle time, etc. are displayed as diagnosis support information. Further, as in the case of abnormality category 1 or 2, the severity may be displayed.

  FIG. 6A shows the relationship between the inspiratory time and the expiratory time obtained from a dynamic image with a normal lung ventilation function. In FIGS. 6A to 6D, MIN indicates a frame image of maximum exhalation, and MAX indicates a frame image of maximum inspiration.

  As shown in FIG. 6A, when the pulmonary ventilation function is normal, the movements of inspiration and expiration are substantially the same starting from the inspiration-to-expiration conversion point. For example, the frame images during inspiration are continuously displayed. The same behavior is obtained when the frame image is reproduced and when the frame image at the time of expiration is rewound and reproduced. Therefore, the inspiratory time and the expiratory time are substantially the same.

  FIG. 6B shows the relationship between the inspiratory time and the expiratory time of the dynamic image determined to be abnormal category = 1. In FIG. 6B, exhalation time> inspiration time. In this case, there is a suspicion of obstructive pulmonary disease in which exhaled air is difficult to ventilate and the taken-in air is delayed.

  FIG. 6C shows the relationship between the inspiratory time and the expiratory time of the dynamic image determined to be abnormal category = 2. In FIG.6 (c), although the expiration time and inhalation time are substantially in agreement, one respiration cycle which is the sum of expiration time and inspiration time is short compared with the time of normal. In this case, there is a suspicion of restrictive pulmonary disease in which the vital capacity decreases and breathing becomes shallower and faster.

  FIG. 6D shows the relationship between the inspiratory time and the expiratory time of the dynamic image determined to be abnormal category = 1 and 2. In FIG. 6D, exhalation time> inspiration time. In addition, one respiratory cycle, which is the sum of exhalation time and inspiration time, is shorter than normal. In this case, there is a suspicion of obstructive pulmonary disease that is difficult to ventilate due to exhalation and delays exhausting the taken-in air, and mixed pulmonary disease that is restricted lung disease in which the vital capacity decreases and breathing becomes shallower and faster.

  As described above, in the first embodiment, the control unit 31 of the diagnostic console 3 analyzes the dynamic image and compares the inspiratory time and the expiratory time to determine whether the lung ventilation function of the subject M is abnormal. Since the diagnosis support information indicating the determination result is displayed on the display unit 34, the patient's own exhalation and inhalation can be performed with less burden on the patient as compared with the examination using lung scintigraphy, spiro examination, etc. It is possible to provide diagnosis support information based on the movement of time to the doctor.

  In addition to the above determination, by determining whether or not the respiratory function of the lungs of the subject M is abnormal based on whether or not one breathing cycle time exceeds a predetermined threshold value, movements during expiration and inspiration are determined. Diagnosis support information related to restrictive lung disease, mixed lung disease, and the like that cannot be determined only by comparison can be provided to the doctor.

  Further, the area of the direct X-ray irradiation region is calculated in each of the series of frame images, the frame image having the maximum area of the calculated direct X-ray irradiation region is specified as the frame image at the maximum expiration, and the direct X-ray irradiation region is directly By specifying a frame image in which the area of the line irradiation region is minimal as a frame image at the time of the maximum inspiration, it is possible to accurately determine an abnormality even for a noisy dynamic image of each frame image.

  In the first embodiment, the expiration time, the inspiration time, and the 1 respiratory cycle time of the entire lung field are calculated, and the diagnosis support information is displayed based on them. The image analysis processing may be executed for each small area. In this way, it is possible to specify in which part of the lung field the ventilation function disorder has occurred. Further, the image analysis processing A may be executed for the region designated by the doctor using the operation unit 33, and diagnosis support information indicating whether or not the region designated by the doctor is abnormal may be displayed.

<Second Embodiment>
Next, a second embodiment of the present invention will be described.

  Since the configuration of the second embodiment, the operation of the imaging device 1 and the imaging console 2 are the same as those of the first embodiment, the description thereof will be omitted, and hereinafter the diagnostic console 3 of the second embodiment. Will be described.

  When the diagnostic console 3 receives a series of frame images of dynamic images from the imaging console 2 via the communication unit 35, the control console 31 and the image analysis processing B program stored in the storage unit 32 The image analysis process B shown in FIG. 7 is executed in cooperation. By executing the processing, an extraction unit, a calculation unit, and a determination unit are realized.

  In the image analysis processing B, first, a frame image at the time of maximum expiration and a frame image at the time of maximum inspiration are extracted from a series of frame images (step S21). The processing in step S21 is the same as the processing described in step S11 in FIG.

  Next, frame images for one respiratory cycle are extracted (step S22). For example, a sequence of frame images from the maximum expiratory frame image of any respiratory cycle to the next maximum expiratory frame image, or a sequence of frame images of the maximum inspiratory frame of any respiratory cycle to the next maximum inspiratory frame image Are extracted as frame images for one respiratory cycle. In the present embodiment, a series of frame images from the maximum expiratory frame image of the first respiratory cycle to the next maximum expiratory frame image are extracted as frame images for one respiratory cycle.

  Next, one respiratory cycle time is calculated based on the extracted number of frame images for one respiratory cycle and the frame rate at the time of imaging (step S23). Since the calculation method of 1 respiration cycle is the same as step S13 of FIG. 4, description is abbreviate | omitted.

  Next, the operator designates a frame image at a timing to be analyzed via the operation unit 33 (step S24). In step S24, for example, together with a message such as “Please click on the image when you want to analyze lung movement”, the frame image extracted in step S22, for example, the first maximum expiration of one respiratory cycle is displayed. The frame images from the frame image to the frame image of the maximum inspiration are displayed as moving images on the display unit 34 or displayed side by side. When the doctor observes the dynamics of the lung field of the patient being displayed as a moving image or a still image, and when the motion unit is clicked on the image by the operation unit 33 at the timing at which it is desired to be analyzed. Specified as a frame image. The designated frame image is called a designated frame.

  Next, the extracted frame image of the start of one respiratory cycle (for example, maximum expiration) is the first frame, and the frame image of the inspiration and expiration conversion point (for example, the maximum inspiration which is the conversion point from expiration to inspiration) is the second. Frame image of one frame and the last (for example, maximum exhalation) frame image of the first breathing cycle as a third frame, and a frame image that most closely approximates the specified frame among the frame images existing between the second frame and the third frame (Referred to as an approximate frame) is extracted (step S25). This approximate frame is an image when the state of the chest of the subject M becomes almost the same as that at the time of photographing the designated frame after the maximum inspiration which is a conversion point between inspiration and expiration. For example, the cross-correlation coefficient between the designated frame and each frame image existing between the second frame and the third frame is obtained by the template matching method, and the frame image showing the maximum cross-correlation coefficient is used as the approximate frame. Extract. In addition, among the frame images existing between the second frame and the third frame, an image whose area value of the lung field region (or direct X-ray irradiation region) is closest to the designated frame is set as the approximate frame. You can also.

  Next, the time from the designated frame to the second frame (time 1) and the time from the second frame to the approximate frame (time 2) are calculated (step S26).

  Next, it is determined whether Time1 and Time2 substantially match (whether they do not match) (step 27). For example, if the difference between Time 1 and Time 2 is within one frame interval time (error range), it is determined that they are substantially coincident. If it is determined that Time1 and Time2 are substantially the same (step S27; YES), the process proceeds to step S29. If it is determined that Time 1 and Time 2 do not match (step S27; NO), it is determined that the lung ventilation function of the subject M is abnormal, and the abnormal classification (here, 1), Time 1 and Time 2 are the control unit 31. (Step S28), and the process proceeds to step S29.

  Next, it is determined whether or not one respiratory cycle time is equal to or less than a predetermined threshold value (step S29). The threshold value in step S29 is a value obtained experimentally and empirically as the lower limit of the normal one respiratory cycle time. If it is determined that one respiratory cycle time is not less than or equal to the threshold value (step S29; NO), the process proceeds to step S31. When it is determined that one respiratory cycle time is equal to or less than the threshold (step S29; YES), it is determined that the lung ventilation function of the subject M is abnormal, and an abnormal classification (here, 2), one respiratory cycle time. Is stored in a predetermined area of the RAM of the control unit 31 (step S30), and the process proceeds to step S31.

  In step S31, the diagnosis support information is displayed on the display unit 34 based on the data stored in the predetermined area of the RAM (step S31), and the image analysis process B ends.

  For example, when no data is stored in a predetermined area of the RAM, “normal” characters and the like are displayed on the display unit 34 as diagnosis support information.

  When abnormality classification = 1 is stored in a predetermined area of the RAM, for example, “abnormal”, Time1, Time2, etc. are displayed as diagnosis support information. In addition, a determination table (similar to the determination table 321 in FIG. 2) that associates a combination of abnormal categories with a disease name and is stored in the storage unit 32 is referred to, and there is a disease name that corresponds to the current abnormal category. The name of the disease is displayed. The storage unit 32 stores the relationship between the difference value between Time 1 and Time 2 and the severity, and stores the severity corresponding to the difference value between Time 1 and Time 2 calculated this time together with the current Time 1 and Time 2, Or it is good also as displaying instead of these.

  When abnormality classification = 2 is stored in a predetermined area of the RAM, for example, “abnormal” is displayed as diagnosis support information, and one respiratory cycle time or the like is displayed. In addition, a determination table (similar to the determination table 321 in FIG. 2) that associates a combination of abnormal categories with a disease name and is stored in the storage unit 32 is referred to, and there is a disease name corresponding to the current case. If so, the disease name is displayed. The storage unit 32 stores the relationship between the one respiratory cycle time and the severity in association with each other, and the severity corresponding to the one respiratory cycle time calculated this time together with the current one respiratory cycle time or this It is good also as displaying instead of.

  When abnormal divisions = 1 and 2 are stored in a predetermined area of the RAM, for example, “abnormal”, Time1, Time2, 1 breathing cycle time, etc. are displayed as diagnosis support information. Further, as in the case of abnormality category 1 or 2, the severity may be displayed.

  FIG. 8A shows the relationship between Time 1 and Time 2 obtained from a dynamic image in which the lung ventilation function is normal. 8A to 8D, MIN indicates a frame image of maximum expiration, MAX indicates a frame image of maximum inspiration, MIDF indicates a designated frame, and MIDB indicates an approximate frame.

  As shown in FIG. 8A, when the lung ventilation function is normal, the movements of inspiration and expiration are substantially the same starting from the inspiration-to-expiration conversion point. For example, continuous frame images during inspiration The movement is similar when the frame is reproduced and when the frame image at the time of expiration is rewound and reproduced. Therefore, the time Time 1 required from the designated frame to the maximum intake and the time Time 2 required from the maximum intake to the approximate frame are substantially the same.

  FIG. 8B shows the relationship between Time 1 and Time 2 of the dynamic image determined to be abnormal classification = 1. In FIG. 8B, Time2> Time1 is satisfied. In this case, there is a suspicion of obstructive pulmonary disease in which exhaled air is difficult to ventilate and the taken-in air is delayed.

  FIG. 8C shows the relationship between Time 1 and Time 2 of the dynamic image determined to be abnormal classification = 2. In FIG. 8C, Time1 and Time2 are substantially the same, but one respiratory cycle is shorter than that in the normal state. In this case, there is a suspicion of restrictive pulmonary disease in which the vital capacity decreases and breathing becomes shallower and faster.

  FIG. 8D shows the relationship between Time 1 and Time 2 of the dynamic image determined to be normal division = 1 and 2. In FIG. 8D, Time2> Time1 is satisfied. One breathing cycle is shorter than normal. In this case, there is a suspicion of obstructive pulmonary disease that is difficult to ventilate due to exhalation and delays exhausting the taken-in air, and mixed pulmonary disease that is restricted lung disease in which the vital capacity decreases and breathing becomes shallower and faster.

  As described above, in the second embodiment, the control unit 31 of the diagnostic console 3 analyzes the dynamic image and determines the time Time1 from the designated frame designated by the operator to the exhalation-inspiration conversion point. Then, it is determined whether or not the lung ventilation function of the subject M is abnormal by comparing the time Time2 from the conversion point of exhalation and inspiration to the approximate frame, and the diagnosis support information indicating the determination result is displayed on the display unit 34. To display. Therefore, whether the ventilation function of the lung is abnormal at the time specified by the patient during the breathing or at the time of the same movement with less burden on the patient compared to the examination using lung scintigraphy, spiro test, etc. It is possible to provide the doctor with diagnosis support information indicating the above.

  In addition to the above determination, by determining whether or not the respiratory function of the lungs of the subject M is abnormal based on whether or not one breathing cycle time exceeds a predetermined threshold value, movements during expiration and inspiration are determined. Diagnosis support information related to restrictive lung disease, mixed lung disease, and the like that cannot be determined only by comparison can be provided to the doctor.

  Further, the area of the direct X-ray irradiation region is calculated in each of the series of frame images, the frame image having the maximum area of the calculated direct X-ray irradiation region is specified as the frame image at the maximum expiration, and the direct X-ray irradiation region is directly By specifying a frame image in which the area of the line irradiation region is minimal as a frame image at the time of maximum inspiration, it is possible to accurately determine an abnormality even with a noisy dynamic image.

  In the second embodiment, Time1, Time2, and 1 breathing cycle time of the entire lung field are calculated and the diagnosis support information is displayed based on these. The image analysis process B may be executed for each small area by dividing the area. In this way, it is possible to specify in which part of the lung field the ventilatory dysfunction occurs. Further, the image analysis processing B may be executed for the region designated by the doctor using the operation unit 33, and diagnosis support information indicating whether or not the region designated by the doctor is abnormal may be displayed.

  The first and second embodiments of the present invention have been described above. However, the description in the above embodiment is a preferred example of the present invention, and the present invention is not limited to this.

  For example, in the first and second embodiments, the diagnosis support information is displayed on the display unit 34. For example, information indicating whether or not there is an abnormality, a disease name, and the like are output by voice. It is good to do.

  In the first embodiment, exhalation time, inspiration time, 1 respiration cycle time, and the like are calculated based on a frame image for one respiration cycle, but exhalation time, inspiration time in a plurality of respiration cycles. The average value of each breathing cycle time may be used as the expiration time, breathing time, and breathing cycle time per breathing cycle.

  For example, in the above description, an example in which a hard disk, a semiconductor non-volatile memory, or the like is used as a computer-readable medium of the program according to the present invention is disclosed, but the present invention is not limited to this example. As another computer-readable medium, a portable recording medium such as a CD-ROM can be applied. A carrier wave is also applied as a medium for providing program data according to the present invention via a communication line.

  In addition, the detailed configuration and detailed operation of each device constituting the dynamic image processing system 100 can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 Dynamic image processing system 1 Imaging device 11 Radiation source 12 Radiation irradiation control device 13 Radiation detection part 14 Reading control device 15 Cycle detection sensor 16 Cycle detection device 2 Imaging console 21 Control part 22 Storage part 23 Operation part 24 Display part 25 Communication Unit 26 bus 3 diagnostic console 31 control unit 32 storage unit 33 operation unit 34 display unit 35 communication unit 36 bus

Claims (6)

Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion When,
Calculation means for calculating the expiration time and the inspiration time of the subject based on the number of extracted frame images for one respiratory cycle and the frame rate at the time of capturing these frame images;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the expiration time and the inspiration time calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
A dynamic image processing system comprising: Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion When,
The extracted frame image of the start of one breathing cycle is a first frame image, the frame image of a conversion point between expiration and inspiration is a second frame image, and the final frame image of the one breathing cycle is a third frame image. And operating means for designating one frame image from among the frame images existing between the first frame image and the second frame image;
An approximate frame image that most closely approximates the designated frame image is extracted from frames existing between the second frame image and the third frame image, and the second frame is extracted from the designated frame image. Calculating means for calculating a time to an image and a time from the second frame image to the approximate frame image based on a frame rate at the time of shooting;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the two times calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
A dynamic image processing system comprising: The calculation means calculates one breathing cycle time of the subject based on the number of frame images for one extracted breathing cycle and the frame rate at the time of capturing these frame images;
The determination means further determines whether or not the lung ventilation function of the subject is abnormal based on whether or not the calculated one respiratory cycle time is equal to or less than a predetermined threshold value. Or the dynamic image processing system of 2. The plurality of frame images are X-ray images;
The extraction unit calculates an area of the direct X-ray irradiation region in each of the plurality of frame images, and specifies a frame image having a maximum area of the calculated direct X-ray irradiation region as a frame image at the time of maximum expiration. The dynamic image processing system according to any one of claims 1 to 3, wherein a frame image in which the calculated area of the direct X-ray irradiation region is minimal is specified as a frame image at the time of maximum inspiration. Computer
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion ,
A calculating means for calculating an expiration time and an inspiration time of the subject based on the number of extracted frame images for one respiratory cycle and a frame rate at the time of capturing these frame images;
Determination means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the expiration time and the inspiration time calculated by the calculation means are inconsistent;
Display means for displaying diagnosis support information indicating the determination result;
Program to function as. Computer
Extraction means for extracting frame images for one respiratory cycle starting from the time of maximum expiration or maximum inspiration from a plurality of frame images obtained by capturing the dynamics of the subject's chest over one cycle time or more of the subject's breathing motion ,
The extracted frame image of the start of one breathing cycle is a first frame image, the frame image of a conversion point between expiration and inspiration is a second frame image, and the final frame image of the one breathing cycle is a third frame image. And operating means for designating one frame image from among the frame images existing between the first frame image and the second frame image,
An approximate frame image that most closely approximates the designated frame image is extracted from frames existing between the second frame image and the third frame image, and the second frame is extracted from the designated frame image. Calculating means for calculating the time to the image and the time from the second frame image to the approximate frame image based on the frame rate at the time of shooting;
Determining means for determining whether or not the lung ventilation function of the subject is abnormal based on whether or not the two times calculated by the calculating means are mismatched;
Display means for displaying diagnosis support information indicating the determination result;
Program to function as.