JP6418091B2 - Chest image display system and image processing apparatus - Google Patents

Description

  The present invention relates to a chest image display system and an image processing apparatus.

  In contrast to still image photography and diagnosis by chest radiation using conventional film / screen and 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, the pulsed radiation is continuously irradiated from the radiation source in accordance with the read / erase timing of the semiconductor image sensor by utilizing the speed of read / erase response of the image data 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 frame images acquired by imaging, a doctor can observe a series of movements of the chest associated with respiratory motion, heart beat, and the like.

  Various techniques for analyzing lung ventilation and blood flow based on dynamic images of the chest have also been proposed. For example, in Patent Document 1, a plurality of difference images are generated by taking a difference between two temporally adjacent images of a plurality of dynamic images, and each corresponding pixel group is generated from the generated plurality of difference images. For each pixel group, it is described that an image is generated and displayed using any one of a maximum value, a minimum value, an average value, and an intermediate value of pixel values for each pixel group as a pixel value for each pixel group.

Japanese Patent No. 4404291

  However, for example, in Patent Document 1, since information of a plurality of difference images is collected into one still image, the amount of information provided to the doctor as compared with the case where all of the plurality of difference images are displayed. There is a problem that there will be less. In addition, in order to examine an abnormal portion without blood flow or ventilation (stagnation), for example, a still image in which the maximum pixel value for each pixel group corresponding to a plurality of difference images is the pixel value for each pixel group However, when there is a strong noise, the value is picked up, the analysis resolution is lowered, and the original low pixel value is not reflected and accurate diagnosis cannot be performed.

  On the other hand, when a plurality of difference images are sequentially displayed (moving image display) in chronological order, a reduction in the amount of information can be prevented. However, since the pixel values of the difference image reflect the dynamics with periodicity, when the pixel values of a plurality of difference images are arranged in time series, the waveform has a periodicity. If the pixel values are out of phase due to the lung field and the left lung field, there is a problem that the screen flickers and it is difficult to accurately diagnose an abnormal part (see FIG. 5A).

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image that is easy to diagnose without a reduction in the amount of information or a reduction in analysis resolution due to noise.

In order to solve the above problems, the invention described in claim 1
Photographing means for obtaining a dynamic image by photographing the dynamics of the chest;
Analyzing the dynamics based on the dynamic image acquired by the photographing unit, and generating an analysis result image consisting of a plurality of frames indicating the dynamic analysis results;
A region dividing means for dividing each frame of the analysis result image into a plurality of regions corresponding to the plurality of frames;
Generating means for generating a moving image for display in which frames to be displayed in the respective regions are shifted so that phases of analysis results in the plurality of regions match;
Display means for displaying the display moving image generated by the generating means,
Is provided.

The invention according to claim 2 is the invention according to claim 1,
A signal waveform of the value of the analysis result is generated for each of the plurality of regions divided by the region dividing unit, and at least one of the maximum point, the minimum point, the intermediate point, and the positive / negative sign of the generated waveform is switched. An extraction means for extracting a frame corresponding to the feature point;
The generating means calculates a frame shift amount for each of the regions so that the frames of the same feature points extracted from each of the plurality of regions are displayed at the same timing, and sets the frames to be displayed in the respective regions. The display moving image shifted based on the calculated shift amount is generated.

The invention according to claim 3 is the invention according to claim 1 or 2,
The display unit displays the analysis result image generated by the analysis unit and the display moving image generated by the generation unit side by side.

An image processing apparatus according to a fourth aspect of the present invention provides:
Analyzing means for analyzing the dynamics based on a dynamic image obtained by photographing the dynamics of the chest, and generating an analysis result image consisting of a plurality of frames indicating the dynamic analysis result;
A region dividing means for dividing each frame of the analysis result image into a plurality of regions corresponding to the plurality of frames;
Generating means for generating a moving image for display in which frames to be displayed in the respective regions are shifted so that phases of analysis results in the plurality of regions match;
Display means for displaying the display moving image generated by the generating means,
Is provided.

  According to the present invention, it is possible to provide an image that is easy to diagnose without a decrease in the amount of information or a decrease in analysis resolution due to noise.

It is a figure showing the whole chest image display system composition in an embodiment of the present invention. 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 performed by the control part of the diagnostic console of FIG. (A) is a pulmonary embolism analysis result image, (b) is a graph which shows the time change of the analysis result value of the left lung field and the right lung field of (a). (A) is a figure which shows a part of analysis result image which the phase of the blood flow analysis result has shifted in the left and right lung fields, (b) is the right lung field region with respect to the analysis result image of (a). It is a figure which shows the moving image shifted 1 frame at a time. It is a figure which shows the example which displayed in parallel the original analysis result image and the phase alignment analysis result image. It is a figure which shows the example of a display of the analysis result image of the past and this time. It is a figure which shows an example of the display of the distance of a lung apex-diaphragm. It is a figure which shows an example of the time change graph of the variation | change_quantity of the distance of a lung apex-diaphragm, a change speed, and a normalization variation | change_quantity. It is a figure which shows an example of the display of the position of a rib cage. It is a figure which shows an example of the display of the position of a heart wall. It is a figure which shows an example of a display of the position of thick blood vessels, such as the aorta and the pulmonary artery near the hilar. It is a figure which shows an example of the display of the area of a lung field. It is a figure which shows an example of the display of the area of a heart. It is a figure which shows an example of the display of a cardiothoracic ratio. (A) is an image obtained by coloring a chest image according to a concentration difference value (concentration ratio) between the inspiratory position and the expiratory position, and (b) is a concentration difference value of (a) for the chest image. It is an image in which coloring is performed according to a value obtained by dividing (concentration ratio) by a lung field area change rate between an inspiratory position and an expiratory position, or a lung apex-diaphragm distance change rate. It is a figure which shows an example of the comparison display of the analysis result with respect to a several moving image. It is a figure which shows an example of the comparison display of the analysis result with respect to a several moving image. It is a figure which shows an example of the comparison display of the analysis result (spatial direction histogram) with respect to a several moving image. It is a figure which shows an example of the comparison display of the analysis result (time direction histogram) with respect to a several moving image. It is a figure which shows the example which displayed the left lung field reversely. It is a figure which shows the example which added the display according to the respiratory state, the sound, and the vibration at the time of image reproduction. (A) is an image before standardizing the color scheme of the kinetic analysis result based on blood pressure and respiratory rate, and (b) is the image after standardizing the color scheme of the kinetic analysis result based on blood pressure and respiratory rate. It is a figure which shows an image. It is a figure which shows typically operation by a non-contact remote control. (A) is a figure which shows typically the patient displayed through the image currently displayed on a wearable display, and a wearable display, (b) is a figure which shows typically the visual field of the operator who is looking at (a). .

  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.

[Configuration of Chest Image Display System 100]
First, the configuration will be described.
FIG. 1 shows an overall configuration of a chest image display system 100 in the present embodiment.
As shown in FIG. 1, a chest image display system 100 includes an imaging device 1 and an imaging console 2 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 chest image display 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 device 1 is imaging means for imaging the dynamics of the chest having a periodicity (cycle), such as changes in the morphology of lung expansion and contraction associated with respiratory motion, heart pulsation, and the like. 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, and the like.

The radiation source 11 is disposed at a position facing the radiation detection unit 13 across the subject M, and irradiates the subject M with radiation (X-rays) according to 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 during continuous irradiation, number of imaging frames per imaging, X-ray tube current value, X-ray tube voltage value, Additional filter types. 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 detection elements (pixels) converted and stored in a matrix are arranged in a matrix. Each pixel includes a switching unit such as a TFT (Thin Film Transistor). The FPD includes an indirect conversion type in which X-rays are converted into electric signals by a photoelectric conversion element via a scintillator, and a direct conversion type in which X-rays are directly converted into electric signals, either of which may be used.
The radiation detection unit 13 is provided to face the radiation source 11 with the subject M interposed therebetween.

  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 to synchronize the radiation irradiation operation and the image reading operation.

[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. The image is displayed for confirming whether the image is suitable for confirmation of positioning or diagnosis by a photographer.
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) and a RAM (Random Access Memory).
) Etc. 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 program for executing the shooting control process shown in FIG. In addition, the storage unit 22 stores radiation irradiation conditions and image reading conditions in association with the examination target region. 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 an image processing device that acquires a dynamic image from the imaging console 2, displays the acquired dynamic image and its analysis result 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 are executed to centrally control the operation of each part of the diagnostic console 3. The control unit 31 functions as an analysis unit, a region division unit, a generation unit, and an extraction unit.

  The storage unit 32 is configured by a nonvolatile semiconductor memory, a hard disk, or the like. The storage unit 32 stores various types of programs including a program for executing image analysis processing by the control unit 31 and data such as parameters necessary for the execution of processing by the program or processing results. 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 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 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 Chest Image Display System 100]
Next, the operation in the chest image display 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. 2 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 control unit 21 and a program stored in the storage unit 22.

  First, the operation unit 23 of the imaging console 2 is operated by the imaging operator, and patient information (name, height, weight, age, sex, etc. of the patient) of the imaging target (subject M) and an analysis target (for example, blood flow or (Ventilation) 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).

  Next, a radiation irradiation instruction by the operation of the operation unit 23 is waited (step S3). Here, when the subject to be analyzed is blood flow, the imaging operator instructs the subject (subject M) to hold his / her breath so that the movement of the lung field due to respiration is not affected. Further, when the analysis target is ventilation, in order to photograph the dynamics of rest breathing, the subject (subject M) is instructed to make it easier to encourage rest breathing. When preparation for imaging is completed, the operation unit 23 is operated to input a radiation irradiation instruction.

  When a radiation irradiation instruction is input by the operation unit 23 (step S3; YES), a photographing start instruction is output to the radiation irradiation control device 12 and the reading control device 14, and dynamic photographing is started (step S4). 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.

Here, in order to enable the photographer to determine whether or not a dynamic image suitable for analysis can be acquired during shooting, a predetermined number of frame images acquired by shooting (for example, in a half cycle or one cycle). A density waveform based on the acquired frame image is generated every time the corresponding number of images is reached, and the display unit 24 is warned when the cross-correlation coefficient (correlation value) with the reference waveform is lower than a predetermined threshold value. A message may be displayed. Alternatively, the warning may be output by voice or vibration. Thereby, when the dynamic image currently image | photographed is a dynamic image unsuitable for an analysis, imaging | photography can be interrupted at an early stage and the exposure of a useless patient can be suppressed.
For the density waveform, for example, an average value of pixel signal values (density values) is calculated for each acquired frame image, and these are arranged in time series (the vertical axis is the signal value (average value), and the horizontal axis is the frame number ( (Plotted in the coordinate space of the elapsed time from the start of imaging)), or an ROI (Region of Interest) is provided to calculate the average value of the signal values in the ROI calculated for each frame image. It is good also as producing | generating by arranging in a series. Further, as a reference waveform, a plurality of reference waveforms having different phases, wavelengths, and shapes for each analysis target are stored in the storage unit 22 in advance, and a cross-correlation coefficient between each reference waveform and the concentration waveform is calculated. The cross correlation coefficient is used for comparison with the threshold. When the reference waveform having the highest cross-correlation coefficient is determined first, only the cross-correlation coefficient between the reference waveform and the concentration waveform may be obtained and compared with the threshold value in the subsequent processing. Thereby, processing time can be shortened.

  When photographing of a predetermined number of frames is completed, the control unit 21 outputs a photographing end instruction to the radiation irradiation control device 12 and the reading control device 14, and the photographing operation is stopped. The number of frames to be captured is the number of frames that can capture at least one heartbeat cycle or one respiratory cycle.

  Frame images acquired by shooting are sequentially input to the shooting console 2 and stored in the storage unit 22 in association with a number (frame number) indicating the shooting order (step S5) and displayed on the display unit 24. (Step S6). The imaging operator confirms the positioning and the like from 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 photographing OK is input by a predetermined operation of the operation unit 23 (step S7; YES), an identification ID for identifying a dynamic image or each of a series of frame images acquired by dynamic photographing is displayed. Information such as patient information, examination target region, radiation irradiation condition, image reading condition, number indicating the imaging order (frame number) is attached (for example, written in the header area of the image data in DICOM format), and the communication unit 25 To the diagnostic console 3 (step S8). 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 S7; NO), a series of frame images stored in the storage unit 22 is deleted (step S9), and this processing is performed. finish. In this case, re-shooting is necessary.

(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 a dynamic image is received from the imaging console 2 via the communication unit 35, the diagram is obtained by cooperation between the control unit 31 and the program stored in the storage unit 32. 3 is executed.

Hereinafter, the flow of image analysis processing will be described with reference to FIG.
First, a dynamic analysis in the lung field region is performed based on a series of frame images, and an analysis result image including a plurality of frames indicating a dynamic analysis result is generated (step S11).

  Specifically, in step S11, first, one frame image is set as a reference image from a series of frame images. Next, a lung field region is extracted from the reference image, and the extracted region is divided into a plurality of small regions (for example, 2 mm square × 2 mm square) including a plurality of pixels. Next, the other frame images are divided into small regions (regions of signal values output from the same detection element of the radiation detection unit 13 used for imaging) of the same pixel position as the small regions of the reference image, and each frame image Regions with the same pixel position in between are associated with each other. Thereby, the region of the analysis target part of the series of frame images is divided into a plurality of small regions composed of a plurality of pixels.

  Any method may be used to extract the lung field region. For example, a threshold is obtained by discriminant analysis from a histogram of signal values (density values) of each pixel of the reference image, and a region having a signal higher than this threshold is primarily extracted as a lung field region candidate. Next, edge detection is performed near the boundary of the first extracted lung field region candidate, and the boundary of the lung field region can be extracted by extracting along the boundary the point where the edge is maximum in a small block near the boundary. it can.

Here, in the present embodiment, when the analysis target is blood flow, imaging is performed in a breath holding state, and when the analysis target is ventilation, imaging is performed during rest breathing. There is almost no displacement of the lung field region due to respiratory motion in the region, and there is little lung field region due to respiratory motion even during rest breathing. The effect of this slight misregistration and the increase in processing time and error caused by performing known local matching processing and warping processing (see JP 2012-5729 A) for correcting misregistration between the frame images. Considering the influence, it is preferable to omit these processes (see JP 2012-110400 A). Therefore, in step S11, an area having the same pixel position as the lung field area (small area) of the reference image is associated as a lung field area (small area) of another frame image.
Although the processing time is required, the corresponding positions of the lung field areas of the reference image and other frame images (positions where the same structure is depicted in the lung field) are aligned by a known local matching process and warping process. It is good also as dividing into a small area | region after performing.

  The reference image is preferably a frame image that minimizes the area of the lung field region. This is because, when each small region of the reference image is associated with another frame image, each small region is not associated with a region outside the lung field region of the other frame image. For example, in the case of analyzing ventilation, it is preferable that the reference image is a frame image of a resting expiratory position. In the resting expiratory position, the diaphragm position is the highest during rest breathing, that is, the area of the lung field area is the smallest, so each small area of the reference image is associated with another frame image. This is because the region is not associated with a region outside the lung field of another frame image. An image of the resting breath position can be acquired by extracting an image having the highest diaphragm position from a series of frame images. Alternatively, a lung field region may be extracted from each frame image, and a frame image having the smallest area of the extracted lung field region (the smallest number of pixels in the lung field region) may be used as an image of a resting breath position.

In step S11, when the division into small regions is completed, dynamic analysis is performed for each small region, and an analysis result image indicating the analysis result is generated. As a method of dynamic analysis, any known method may be used. For example, the following (1) to (3) may be used.
(1) When the analysis target is blood flow, for example, the method described in JP2012-239796A can be used. That is, with respect to the pulsation signal waveform from the start of imaging, the pulsation signal waveform and each small region are shifted for each of the small regions while shifting the blood flow signal waveform by one frame interval (shifting in the time axis direction). As a blood flow analysis result image, a cross-correlation coefficient with a blood flow signal waveform is calculated, and a moving image in which an image showing the calculated cross-correlation coefficient in each small region is arranged as one frame every time one frame is shifted. It may be generated.
The blood flow signal waveform is obtained by applying a high-pass filter process in the time axis direction (for example, a low-frequency cutoff frequency of 0.8 Hz) to each small region of a series of frame images, and then the signal value of each pixel in the small region. It can be obtained by calculating a representative value (average value, maximum value, etc.) and acquiring a waveform indicating a temporal change of the calculated representative value.
Any of the following can be used as the pulsation signal waveform.
(A) An ROI (region of interest) is defined in the heart region (or aorta region), and a waveform indicating a time change of a signal value in the ROI (b) A signal waveform obtained by inverting the waveform of (a) (c) ECG detection Electrocardiogram signal waveform obtained from sensor (d) Signal waveform indicating heart wall motion (position change) Further, the cross-correlation coefficient can be obtained by the following [Equation 1].

(2) When the analysis target is a blood flow, as described in JP 2013-81579 A, high-pass filtering in the time axis direction (for example, a low-frequency cutoff frequency of 0.8 Hz) is described for each of the small regions described above. ), The difference value of the representative value (average value, maximum value, etc.) of the signal value of each pixel in the small area between the adjacent frame images is calculated, and the difference value calculated between the adjacent frame images May be generated as a blood flow analysis result image. The inter-frame difference image generated by the above method is an image showing the signal change due to the blood flow in each small region from which the signal change due to ventilation in each small region is removed.

(3) When the analysis target is ventilation, as described in Japanese Patent Application Laid-Open No. 2013-81579, low-pass filter processing (for example, a cut-off frequency of 1.0 Hz) in the time axis direction is performed for each of the small regions described above. The difference value of the representative value (average value, maximum value, etc.) of the signal value of each pixel in the small area between adjacent frame images is calculated, and the difference value calculated between each adjacent frame image is A moving image in which images shown in the region are arranged in time series as one frame may be generated as a ventilation analysis result image. The inter-frame difference image generated by the above method is an image showing the signal change due to the ventilation in each small region from which the signal change due to the blood flow in each small region is removed.

  When the analysis result image is generated, each frame of the generated analysis result image is divided into a plurality of regions corresponding to each other (step S12).

Here, the analysis result value, which is the value of the analysis result image obtained by analyzing the dynamic image obtained by photographing the dynamics of the periodic subject, is arranged in the frame order (time series) of the analysis result image. Reflects the period and changes almost periodically. However, depending on the disease, the analysis results may be out of phase for each region in the lung field (see FIG. 4B).
For example, in patients with obstructive pulmonary disease, airway resistance / pulmonary compliance increases, residual air volume increases, ventilation rate decreases, and ventilation may be partially delayed. In the case of a patient with pulmonary embolism, the blood flow in the lung field where the embolus exists tends to be delayed compared to the other due to the presence of an embolus in which the blood vessel is not completely blocked. In such a case, the analysis result phase shifts depending on the region in the lung field.
In step S12, the lung field region, which is the analysis target region of each frame, is divided in units in which a phase shift of the analysis result occurs according to, for example, the condition of the subject.

  For example, the example of pulmonary embolism shown in FIGS. 4A and 4B (FIG. 4A is based on the analysis method of (1) above (cross-correlation coefficient between pulsation signal waveform and blood flow signal waveform). The obtained analysis result image, FIG. 4B, is a graph showing the time change of the analysis result value of the left lung field and the right lung field in FIG. 4A), and the peak (maximum point) of the right lung field. In comparison, the peak in the left lung field is delayed by about 2 frames. In such a case, the lung field region is divided into two regions, a left lung field and a right lung field.

In the case of the lung field area, in addition to dividing into two areas of the left lung field and the right lung field, for example, it is divided into three (two) areas, upper, middle, and lower (up and down), Although it is possible to divide into six (four) areas combining left and right (upper and lower and left and right), how to divide is not particularly limited. However, since the phase shift of the analysis result is at least the analysis unit divided in step S11, the region division in step S12 is divided into regions larger than the small region which is the analysis unit divided in step S11.
Note that how to divide can be input (selected) by the user through the operation unit 33.

  Next, a display moving image is generated by shifting the frames to be displayed in each region so that the phases of the analysis results in the plurality of regions divided in step S12 match (step S13).

  Specifically, in step S13, first, representative values (for example, average value, maximum value, mode value, etc.) of signal values (analysis result values) are calculated for each region of each frame of the analysis result image. This is used as an analysis result value for each region. Next, the analysis result values are arranged in the frame order of the analysis result image for each region to generate a signal waveform of the analysis result, and at least one of the points where the maximum point, the minimum point, the intermediate point, and the positive / negative sign are switched for each region. A frame corresponding to the feature point is extracted. Then, other frames based on one region are used so that the extracted frames of the same feature points are displayed at the same timing, that is, the phases of the analysis results of the respective regions are displayed in agreement with each other. The shift amount of the frame of the region portion (the number of frames indicating how many frames are shifted to display the same phase as the reference region) is calculated (the shift amount may be 0). Then, based on the calculated shift amount, the frame to be displayed in each area is shifted (shifted) to reconstruct a moving image that matches the phase of the analysis result of each area, and to each small area of the reconstructed moving image A display moving image is generated with a color corresponding to the value of the analysis result. For example, in the cases shown in FIGS. 4 (a) and 4 (b), the right lung field region is left as it is, and the left lung field region is shifted between the right and left lung field regions by shifting each frame forward by two frames. A display moving image having the same phase is generated.

For example, when the analysis result image is an inter-frame difference image in breathing, the timing of the inspiration peak can be adjusted over the entire lung by shifting the frame so that the maximum points of each region are displayed at the same timing. Further, by shifting the frame so that the local minimum points of each region are displayed at the same timing, the timing of the peak of expiration can be adjusted over the entire lung field. In addition, by switching the frames so that the points at which the sign of each region changes are displayed at the same timing, the timing of switching between expiration and inspiration can be adjusted over the entire lung field.
When the analysis result image is an image obtained by calculating the cross-correlation coefficient between the pulsation signal waveform and the blood flow signal, by shifting the frame so that the maximum point of each region is displayed at the same timing, The timing at which the blood flow signal waveform most closely matches the pulsation signal waveform can be displayed together.

The generated display moving image is displayed (moving image display) on the display unit 34 (step S14), and the image analysis process is ended.
The generated analysis result image and display moving image are stored in the storage unit 32 in association with the patient information, the examination target part, the analysis target, the date, and the like.

  FIG. 5A shows a part of an analysis result image (cross-correlation coefficient) in which the phases of blood flow analysis results are shifted in the left and right lung fields. In this analysis result image, the i-th frame is the peak of the analysis result value of the left lung field, the i + 1-th frame is the peak of the analysis result value of the right lung field, and the analysis result phase is shifted by one frame on the left and right. Yes. Thus, if the analysis results are out of phase in the left and right lung fields, the screen will flicker when displayed as a moving image. In addition, when looking at one frame, there is an abnormal region where the correlation between the pulsation signal waveform and the blood flow signal waveform is low in the entire lung field (for example, a region where the blood flow is small or stopped). It is not possible to judge whether or not. Therefore, diagnosis cannot be performed efficiently.

  5B, the image analysis processing steps S12 to S13 are performed on the analysis result image of FIG. 5A, and the lung field region is divided into two regions of the left lung field and the right lung field. A part of a moving image in which the right lung field region (the left lung field in FIG. 5A) is shifted forward by one frame is shown. In the moving image shown in FIG. 5B, the analysis results have the same phase in the left and right lung fields, so that it is possible to provide an easy-to-diagnose image with reduced screen flicker. In addition, when one frame is viewed, there is a region where the correlation between the pulsation signal waveform and the blood flow signal waveform is low in the entire lung field (for example, an abnormal region where the blood flow is small or has stopped). It can be determined whether or not. In addition, in an image (called a MIP (Maximum Intensity Projection) image) in which the maximum value of analysis results is aggregated into one still image, the value is picked up when there is strong noise, and a low analysis result value is reflected. (For example, an abnormal region where the correlation between the pulsation signal waveform and the blood flow signal waveform is low does not appear on the MIP image), but such noise does not occur. That is, it is possible to provide an easy-to-diagnose image without a decrease in the amount of information or a decrease in analysis resolution due to noise as compared with the conventional case.

  In step S14, as shown in FIG. 6, the analysis result image (original analysis result image) that has not been subjected to the above-described phase alignment and the analysis result image (phase alignment analysis result image) that has undergone phase alignment are used. May be displayed in parallel. Alternatively, the original analysis result image and a specific one frame (for example, the frame of the maximum point) of the phase matching analysis result image may be displayed in parallel. Thereby, it is possible to confirm the phase shift of the analysis result in the lung field region, and at the same time, it is possible to efficiently confirm whether there is an abnormal portion of blood flow or ventilation.

  Alternatively, a specific frame of the original analysis result image and the phase matching analysis result image may be displayed in a superimposed manner. For example, one specific frame (for example, the frame of the maximum point) of the phase matching analysis result image whose transparency can be adjusted is superimposed and displayed on the original analysis result image displayed as a moving image. Accordingly, it is possible to simultaneously check whether there is a phase shift of the analysis result in the lung field region and whether there is an abnormal portion of blood flow or ventilation without moving the line of sight.

  Further, the phase matching analysis result image generated based on the current imaging and the past phase matching analysis result image of the same part of the same patient may be displayed as a moving image in parallel. In this case, the number of frame images acquired and the interval between frame images may differ between the previous dynamic shooting and the current dynamic shooting. In such a case, the past phase matching analysis result image and the current phase matching are different. From each analysis result image, a frame of a specific feature point (for example, a frame corresponding to a maximum point, a minimum point, an intermediate point thereof, a point where a positive / negative sign is switched, etc. for one cycle of the analysis result value) is extracted. It is preferable to thin out frames other than the extracted frames and to display moving images in parallel by matching the phases of both images. Alternatively, the speed at which the frames of the past and current analysis result images are displayed may be adjusted so that the frames of the same feature point are displayed at the same time without thinning out. In this way, it becomes possible to easily compare analysis results of past blood flow and ventilation.

  Further, as shown in FIG. 7, for each of the past and current analysis result images, a specific frame (for example, a frame of local maximum points) of the phase matching analysis result image is generated, and the past still image and the current still image are generated. A difference image is generated by calculating a difference between analysis result values of corresponding positions of the image, and a difference image in which an absolute value of the difference value is colored in a region equal to or larger than a predetermined threshold is displayed on the display unit 34. It is good. Thereby, it becomes possible for a doctor to easily identify a portion where the blood flow or ventilation function has decreased or improved.

As described above, according to the diagnostic console 3, the control unit 31 performs dynamic analysis based on the dynamic image of the chest transmitted by the imaging console 2, and from a plurality of frames indicating the dynamic analysis results. An analysis result image is generated. Then, each frame of the analysis result image is divided into a plurality of regions corresponding to each other between the plurality of frames, and the frames to be displayed in each region are shifted so that the phases of the analysis results in the plurality of divided regions match. Generate a moving image. Specifically, for each of the plurality of divided areas, a signal waveform of the value of the analysis result is generated, and at least one of the points where the maximum point, minimum point, intermediate point, and positive / negative sign of the generated waveform are switched The frame corresponding to the point is extracted. Then, the moving amount of the frame is calculated for each region so that the extracted frames of the same feature points are displayed at the same timing, and the moving image is obtained by shifting the frame to be displayed in each region based on the calculated shifting amount. Is generated. Then, the generated moving image is displayed on the display unit 34.
Therefore, it is possible to provide an image that is easy to diagnose without a decrease in the amount of information or a decrease in analysis resolution due to noise.

  In addition, for example, by displaying the original analysis result image before shifting the frame and the phase-matched image with the phase shifted to align the phase, the phase shift of the analysis result in the lung field region can be confirmed. At the same time, it is possible to efficiently check whether there is an abnormal part of blood flow or ventilation.

  The description in the present embodiment is an example of a suitable chest image display system according to the present invention, and the present invention is not limited to this.

  For example, the small area in the above embodiment is not limited to being constituted by a plurality of pixels, and may be an area constituted by one pixel unit.

For example, in the above description, an example in which a hard disk, a semiconductor nonvolatile 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. CD-ROM as other computer-readable medium
It is possible to apply a portable recording medium such as the above. Further, a carrier wave is also applied as a medium for providing program data according to the present invention via a communication line.

Further, the diagnostic console 3 can calculate the following feature amount by analyzing the dynamic image of the chest.
For example, the feature amount calculated based on the density change of the dynamic image includes the calculation of the density within the ROI block, the ratio of the density change (density change speed) of different body regions (for example, the density change (density) associated with the heartbeat on the heart Change rate) and the concentration change (concentration change rate) associated with breathing in the lung field), concentration amplitude, airflow velocity, difference or quotient between specified frames, concentration waveform cross-correlation, concentration phase (phase shift), expiration time , Inspiratory time, respiratory cycle, heartbeat cycle, and the like. In addition, a phase animation that visualizes the timing of the respiratory cycle based on the concentration waveform of the dynamic image is displayed, a histogram of the distribution of the feature amount is displayed, and the spatial direction or time direction of the feature amount is displayed. Standard deviation can also be displayed.

  Features calculated based on the shape of the structure in the dynamic image include location trajectories (diaphragm, diaphragm flatness, lung apex-diaphragm distance, rib cage, rib, clavicle, scapula, heart wall, Thick blood vessels such as the pulmonary artery near the aorta and hilar), area (lung area, heart area), length (distance) between two points on the graph or image, angle (lateral angle, clavicle angle relative to horizontal plane, rib Angle, spine angle with respect to the midline), respiratory cycle, heartbeat cycle, ratio of movement amounts (movement speeds) of different body structures, ratio of feature amount using density change and feature amount using shape change, and the like.

  As for the distance between the lung apex and the diaphragm, as shown in FIGS. 8A and 8B, for example, the position of the expiration position and the position of the diaphragm at the inspiration position are displayed on the image at the inspiration position. FIG. 8A shows the reference position of the diaphragm as a straight line when calculating the distance between the lung apex and the diaphragm between the expiration position and the inspiration position. FIG. 8B shows the outline of the lower end of the diaphragm at the expiration and inspiration positions. Moreover, as shown in FIG. 9, it is good also as calculating the change amount and change speed of the distance of the lung apex-diaphragm, and displaying the time change graph. The amount of change in the apex-diaphragm distance is the normalized change in the apex-diaphragm distance, which is normalized by the average distance of the apex-diaphragm (that is, the average length of the lung in the longitudinal direction). Is preferred. Respiratory function (lung size) changes according to height, gender, age, etc., but by standardizing the amount of change with lung size (length), those effects can be eliminated, and individuals This is because it becomes possible to compare the ventilation function with accuracy. With these displays, the doctor can grasp the amount of expansion and contraction of the lungs accompanying the breathing and the speed. It is also possible to grasp the intensity, cycle, and timing of chest breathing.

  As for the position of the thorax, as shown in FIG. 10, for example, the positions of the exhalation position and the outer side and the inner side of the thorax (lung field) in the inspiratory position are displayed on the inspiratory position image. Also, as shown in FIG. 9, the change amount and change speed of the position of the rib cage may be calculated, and the time change graph thereof may be displayed. Further, the change amount of the rib cage width and the changing speed of the rib cage width may be calculated, and the time change graph thereof may be displayed. The change amount of the rib cage width is preferably a normalized rib width change amount obtained by normalizing the rib width change amount by the average value of the rib width for the same reason as the change amount of the lung apex-diaphragm distance. With these displays, it becomes possible for the doctor to grasp the amount of expansion / contraction and speed of the lungs accompanying breathing. It is also possible to grasp the intensity, cycle, and timing of chest breathing.

  As for the position of the heart wall, as shown in FIG. 11, the contours of the heart wall at the end of diastole and end of systole are displayed on the chest image. Moreover, as shown in FIG. 9, it is good also as calculating the variation | change_quantity and change speed | rate of the position of a heart wall, and displaying the time change graph. Alternatively, the change amount of the heart width and the change speed of the heart width may be calculated and a time change graph thereof may be displayed. For the same reason as the change in the distance between the pulmonary apex and the diaphragm, the change in the heart width is a value of the heart width change rate obtained by dividing the heart width change amount by the average heart width and its time change graph (heart width change rate graph). ) Is preferably displayed. The size (width) of the heart changes depending on the physique and age, but by standardizing the amount of change in the width of the heart by the size (width), the influence of the physique and age can be eliminated, and for each individual This is because it is possible to compare cardiac functions with high accuracy. With these displays, the doctor can grasp the heart size, amount of movement, direction of movement, timing of movement, and the like.

  As for the position of large blood vessels such as the aorta and pulmonary artery near the hilar, as shown in FIG. 12, the blood vessel contours at the end of diastole and end of systole (or inspiratory and expiratory) are displayed on the chest image. To do. Further, as shown in FIG. 9, the change amount and change speed of the position of the blood vessel may be calculated, and the time change graph thereof may be displayed. Further, the blood vessel diameter change amount and the blood vessel diameter change speed may be calculated and a time change graph thereof may be displayed. As the blood vessel diameter change amount, it is preferable to display a blood vessel diameter change rate value obtained by dividing the blood vessel diameter change amount by the average cardiovascular diameter and a time change graph thereof. With these displays, the doctor can grasp the movement / direction / timing of blood vessels (peripheral alveoli) and changes in blood vessel diameters associated with heartbeat or respiration. When the composition around the blood vessel (for example, the alveoli) is hard, the amount of movement associated with breathing and heartbeat is reduced, so that a local lung disease can be detected. In addition, it is possible to detect vascular diameter hypertrophy associated with pulmonary hypertension, heart failure, or the like based on the size, amount of change, and rate of change of the blood vessel diameter.

  As for the area of the lung field, as shown in FIG. 13, for example, the outlines of the expiratory position and the lung field at the inspiratory position are displayed on the inspiratory position image. Moreover, as shown in FIG. 9, it is good also as calculating the change amount and change speed of a lung field area, and displaying the time change graph. As the lung field area change amount, it is preferable to display a value of the lung field area change rate obtained by dividing the lung field area change amount by the average lung field area and a temporal change graph thereof. The size (area) of the lung changes depending on the height, sex, and age, but by standardizing on the size of the lung, those effects can be eliminated, and the ventilation function of each individual This is because the comparison can be made with high accuracy. With these displays, the doctor can grasp the size of the lung and its change.

  As for the area of the heart, as shown in FIG. 14, the outline of the heart in the diastole and systole is displayed on the chest image. Moreover, as shown in FIG. 9, it is good also as calculating the variation | change_quantity and change rate of a heart area, and displaying the time change graph. As the heart area change amount, it is preferable to display a heart area change rate value obtained by dividing the heart area change amount by the average heart area and its time change graph. The size (area) of the heart changes depending on the height, gender, and age, but by standardizing with the size of the heart, it is possible to eliminate these effects, and the cardiac function of each individual This is because the comparison can be made with high accuracy. With these displays, the doctor can grasp the size of the heart, the amount of movement, the timing of movement, and the like.

Examples of the ratio of movement amounts (movement speeds) of different body structures include CTR ratio (cardiothoracic ratio), ratio of diaphragm movement amount (movement speed) and rib (or clavicle) movement amount (movement speed), diaphragm There are two different movement amounts (ratio of movement speeds).
The cardiothoracic ratio is a percentage of the ratio of the heart width to the rib cage width. As shown in FIG. 15, a cardiothoracic ratio measurement line superimposed on a chest image, a cardiothoracic ratio value and its time change graph, a cardiothoracic ratio time change speed value and its time change graph, etc. Is displayed. With these displays, the doctor can grasp the degree of expansion of the heart. In addition, it is possible to know the amplitude (maximum to minimum) of the cardiothoracic ratio from the time change and the speed of time change of the cardiothoracic ratio, which cannot be obtained with conventional still images, and more accurately circulatory function abnormalities (for example, lung high pressure) Disease, pulmonary embolism, heart failure, etc.) can be detected.

Examples of the ratio between the feature amount using the density change and the feature amount using the form change include the following (1) and (2).
(1) Concentration difference value (concentration ratio) between the inspiratory position and the expiratory position (see Fig. 16 (a)), the change in the lung field area between the inspiratory position and the expiratory position, or the change in the distance between the lung apex and the diaphragm Divide (weight) (see FIG. 16B).
For the density difference value (density ratio), for example, local (local block average), single lung field average, and whole lung field average are calculated. As a display method, for example, as shown in FIG. 16B, a still image (or moving image) colored according to the value after division is displayed.
By comparing the magnitude of the morphological change and the magnitude of the concentration change, for example, an abnormal ventilation function associated with an obstructive disease, restrictive disease, or the like can be detected. For example, it can be seen that when the concentration change (alveolar expansion / contraction amount) is small while the form (thorax and diaphragm) moves well, the ventilation function is reduced. As the feature amount using the morphological change here, the distance change rate of other body parts accompanying breathing, such as “rate change rate of rib cage” and “change rate of intercostal distance”, may be used.
(2) Divide (weight) the concentration difference value (concentration ratio) between the end diastole and the end systole by the rate of change in heart area (heart wall width) between the end diastole and the end systole period.
Concentration difference value (concentration ratio) is calculated, for example, for each local area (local block average), whole heart average, left ventricular average, left atrial average, right ventricular average, right atrial average, aorta, and pulmonary artery To do. The display mode is the same as in FIG. By comparing the magnitude of the morphological change and the magnitude of the concentration change, for example, abnormal cardiac functions such as pulmonary hypertension and heart failure can be detected. For example, if the concentration change (blood volume change) is small for the movement of the form (heart wall), it can be seen that the cardiac function is degraded.

The diagnostic console 3 has the following display functions.
For example, functions for displaying multiple images include parallel display of multiple images, simultaneous playback of multiple images, video playback with the same cycle of each video, optimization of the playback start frame number and playback speed of each video, The ROI set on the image is displayed simultaneously on multiple images, the ROI is displayed individually on multiple images, the waveform of each moving image is displayed on the same graph (with normalization function), the images are expanded at the same time, and the images are displayed at the same time Functions such as moving to each image, rotating each image at the same time, and unifying the density and contrast of each image.

  The diagnostic console 3 has a function of comparing and displaying the analysis result of the designated frame as follows for a plurality of moving images.

For example, it has a function of extracting and displaying a concentration difference value (concentration ratio) by extracting frames of the same respiratory phase (same cardiac phase) from two moving images. For example, the concentration difference value (concentration ratio) is calculated as a local average, a single lung field average, a lung field average, or the like.
Also, for example, as shown in FIG. 17, two frames of the same respiratory phase (same cardiac phase) are extracted from each of the two moving images, and each local (local block average), within a specific ROI (average), or all images It has a function of calculating a density difference value (density ratio) in a range (one frame), and calculating and displaying a difference (ratio) between density difference values (density ratios) calculated between two moving images.
From the conventional still image, even in the same patient, there is a slight difference in respiratory phase (or cardiac phase) for each radiograph, and when measuring changes over time such as concentration values, the biological composition in the lung field is It was not possible to distinguish whether the "concentration value changed due to improvement by treatment" or "the concentration value changed because the respiratory phase (cardiac phase) was shifted (alveolar density changed)" . As described above, density analysis using the frames of approximately the same phase from the two videos can make the density change due to the shift of the respiratory phase (or cardiac phase) almost zero, so the change with time can be accurately performed. It becomes possible to measure.

Also, as shown in FIG. 18, a function of extracting frames of the same respiratory phase (same cardiac phase) from two moving images, calculating a CTR value from each frame, and displaying a cardiothoracic ratio measurement line superimposed on the chest image. Have Moreover, it has a function of displaying a value of a cardiothoracic ratio, a time change graph of the cardiothoracic ratio, and a time change speed graph of the cardiothoracic ratio for each moving image.
In the past, it was difficult to distinguish whether “the CTR value changed as the stage progressed or improved” or “the CTR value changed due to a shift in respiratory phase (or cardiac phase)”. This makes it possible to calculate a CTR value that is not affected by respiration or heartbeat, so that a more accurate comparison (comparison with the same subject over time, comparison with another person) can be performed, and diagnostic ability is improved.

Further, as shown in FIG. 19, a spatial histogram (for example, a density histogram) of frames of the same respiratory phase (same cardiac phase) extracted from two moving images is generated and compared and displayed. Or, in addition, it has a function of displaying the difference (quotient) result of the histogram of each image.
Further, as shown in FIG. 20, a frame having an equivalent phase range is extracted from two moving images, and a time-direction histogram (for example, a density histogram) or a spatial direction + time-direction histogram is compared and displayed. Or, in addition, it has a function of displaying the difference (quotient) result of the histogram of each moving image.
Previously, it was difficult to distinguish whether the histogram changed as the stage progressed or improved, or whether the histogram changed due to a shift in respiratory phase (or cardiac phase). Since a histogram that is not affected by heart rate or heartbeat can be calculated, a more accurate comparison (comparison with the same subject over time, comparison with another person) can be performed. In addition, by taking the difference (quotient) of the histogram calculated from substantially the same phase image, it becomes easy to grasp the difference, and the diagnostic ability (such as grasping the presence or absence of the stage progression or the presence or absence of the medication effect) is improved.

  In addition, the diagnostic console 3 superimposes a function for displaying an arbitrary area of the image in color, a function for displaying the arbitrary area of the image with a color lightness color scheme, a function for switching and displaying the arbitrary image area, and an arbitrary image area as a playback function. A function to display, a function to display a lung field frame in an arbitrary area of the image, a new image highly relevant to the vicinity of the image currently being displayed or reproduced (for example, a past image, the same disease image, a comparative healthy person image, etc. ) Automatically display function, function to move / rotate / invert / enlarge / reduce an arbitrary area of the image, and display (character / color scheme), sound, and vibration according to the breathing state during image (video) playback Function, function to normalize image density contrast and color scheme according to subject's condition (mind / body characteristics, vital signs, positioning), display function of usage history (image display date, user, frequency, etc.) It has a function for 3D display of image density, a function for setting a playback (start to end) frame of a moving image, a function for changing a playback speed (frame advance, slow, fast forward, reverse playback) and the like.

  The function to move / rotate / invert / enlarge and display an arbitrary area of the image and display the image is specifically displayed side by side in the area to be compared or displayed / reproduced, or displayed / reproduced in an overlapping manner ( This is a function for displaying a variable (transparency, variable display) and displaying a difference (or taking a difference after warping). FIG. 21 is an example of this, and shows a case where the left lung field is inverted and displayed side by side in the right lung field. By having such a display function, it becomes easy to grasp the difference (left-right difference) in the form and function of the left and right lungs. As a result, it becomes easy to find local abnormalities (alveoli, blood vessel distribution, ribs, collarbones, etc.).

Functions that add display (text / color), sound, and vibration according to the respiratory state during image (video) playback include, for example, respiration phase recognition based on the concentration waveform and diaphragm position acquired based on dynamic images. This function reflects the state (inspiratory position or expiratory position, etc.) on sound and display (characters, color scheme). Alternatively, it is a function that changes the intensity and type of sound and display (characters, color scheme) according to the density change speed and the position change speed of the diaphragm. FIG. 22 shows an example of this function. As shown in FIG. 22, for example, Sue is output at the inspiratory position, Har is output at the expiratory position, and silence is output at the time of breath holding. In addition, characters such as “inspiratory position” and “exhaled position” are displayed on the image according to the respiratory phase. Further, the color scheme of the image is arbitrarily changed according to the respiratory phase (for example, “the inspiratory position is green to white”, “the expiratory position is blue to white”, etc.). Further, the vibration is changed according to the respiratory phase (vibration is large at the inspiratory position → no vibration at the expiratory position).
This function improves the diagnostic ability because the respiratory state can be grasped more intuitively. In addition, when breathing is weak, it is difficult to grasp the breathing state (breathing phase) by visual observation because the change in density, diaphragm movement amount, and thorax movement amount are small in the conventional black and white color moving image. Accordingly, by changing the “sound”, “color scheme”, etc., it becomes easy to grasp the respiratory phase, and it becomes easy to detect an abnormal ventilation function when breathing is weak.

As shown in FIG. 23, the functions for normalizing the density contrast and color scheme of the image according to the condition of the subject (mind / body characteristics, vital signs, positioning) are subjects such as heart rate, respiratory rate, standing or standing position, etc. The density contrast and color scheme of the image are standardized and changed according to the state. FIG. 23A shows an image before normalization, and FIG. 23B shows an image after normalization. Examples of subject conditions that change density contrast include, for example, respiratory rate, respiratory depth (factors affecting respiratory function), blood pressure, pulse rate, body temperature (factors affecting blood flow), and imaging positioning. (Standing or lying), age, gender, obesity, BMI, race, nationality, etc.
Even in healthy individuals, blood pressure and respiratory rate change depending on the shooting date, and the dynamic analysis results also slightly change accordingly, but by standardizing the color scheme of the dynamic analysis results based on blood pressure and respiratory rate, the same standard can be used. Can be compared. Also, depending on the severity of the patient, the radiographic positioning may be changed (in the case of severe, standing position, in the case of mild or healthy condition), but the circulatory function and ventilation function will inevitably change depending on the standing position or position. Therefore, there is a problem that it is difficult to accurately compare the results obtained in the past in the supine position (dynamic analysis results) with the results recently taken in the standing position (dynamic analysis results). If so, it is not known whether it is caused by “stage progression or improvement by treatment” or “positioning is different”). Therefore, by standardizing the color scheme of the dynamic analysis results based on the imaging positioning information, it is possible to accurately compare past dynamic analysis results with different imaging positioning, and changes over time (stage progression, therapeutic effect, etc.) Is easier to grasp.

In addition, the diagnostic console 3 has data saving functions such as ROI size, ROI coordinate saving / reading function, a function for trimming and saving a specified frame (time), an analysis result (feature value analysis result such as interframe difference, graph, etc. Comment, annotation data, patient information, etc.), annotation addition, storage function, analysis result (feature value) storage function.
Further, the diagnostic console 3 has, as an image display adjustment function, a density / contrast adjustment function, an enlarged display function, and a function for compressing and displaying an image.

  Moreover, the diagnostic console 3 has an operation function by a non-contact remote controller as shown in FIG. Specifically, it has a function of selecting an image to be displayed, image reproduction, analysis, and the like by gesture recognition (movement of limbs and eyes, facial expressions), voice recognition, electroencephalogram recognition, and cerebral blood flow recognition. This makes it possible to perform operations such as dynamic analysis result display, graph display, video playback, and enlarged display of the image area of interest even in environments where hygiene and emergency screen operations cannot be performed with a mouse, such as in an emergency disaster or during surgery. Improved workflow.

Further, the diagnostic console 3 has a function of displaying an image and a dynamic analysis result (functional image) on the wearable display D as shown in FIG. In the field of view of the operator O wearing the wearable display D, as shown in FIG. 25 (b), the patient P can see the image superimposed on the part corresponding to the image. This makes it possible to alternately display the visual inspection information of the patient P, which can be seen directly by visual inspection, and "Vital information such as X-ray images displayed on the wearable display, dynamic analysis results (functional information), and blood pressure" in emergency disasters and during surgery. By viewing or superimposing them, visual inspection and confirmation of test results such as images can be performed simultaneously, enabling more speedy diagnosis and treatment. In addition, the diagnostic console 3 analyzes who is the patient P who is paying attention to the operator O wearing the wearable display D based on sensor information such as an optical camera (not shown) mounted on the wearable display D, and operates the diagnostic console 3. A function of automatically displaying “X-ray image, dynamic analysis result (function information), vital information such as blood pressure”, etc., on the wearable display D related to the patient P that the person O is paying attention to may be provided. As a result, the operator can quickly collect necessary information even in an emergency or disaster scene, and appropriate diagnosis and treatment can be performed.
Further, the diagnostic console 3 has a function of notifying the user of an abnormality by display, sound, vibration or the like based on the dynamic analysis result (function information) being displayed. Thereby, even if the user does not always look at the display screen, the user can notice the abnormality of the subject, and accurate diagnosis and treatment can be performed earlier.

  The imaging console 2 may have a function for determining and displaying imaging conditions based on past images. Analyze image quality indicators such as S / N in the region of interest for still images or video data acquired in the past for which shooting conditions such as tube current, exposure conditions, and SID (Source Image receptor Distance) are known. Alternatively, the imaging conditions of the dynamic image necessary for diagnosing the region of interest may be calculated, and the calculated imaging conditions may be displayed on the display unit 24. Alternatively, an image photographed under the computed photographing condition may be sent to the diagnostic console 3 to analyze the dynamic image, or display the result of the dynamic image on the display unit 34.

In addition, the radiation detection unit 13, the imaging console 2, or the diagnostic console 3 preferably has a function of optimizing the filter processing based on the frequency characteristics in the time direction of the radiation output as a preprocessing function of the feature amount analysis. .
In round-trip and portable radiation generators, the radiation output is not stable, and the radiation output may continue to rise or fall suddenly or repeatedly rise and fall. In that case, in order to extract signal changes caused by the heartbeat and breathing of the body, the frequency characteristics of the high-pass filter and low-pass filter prepared in advance are insufficient to reduce the signal change due to the increase and decrease of the radiation output. Therefore, it is impossible to distinguish whether “a signal change occurs due to heartbeat or respiration” or “a signal change occurs due to an increase or decrease in radiation output”. Therefore, the radiation detector 13, the imaging console 2, or the diagnostic console 3 detects the frequency characteristics of the radiation output of the radiation generator before or during imaging, and based on the detected frequency characteristics, a high-pass filter or It has a function to correct the frequency characteristics of the low-pass filter, band-pass filter, or band-stop filter, and to perform image correction processing that sufficiently reduces the “signal change due to the rise and fall of radiation output” that occurs in the time direction of the image data. preferable. By mounting such radiation output frequency characteristics grasping, filter performance correction processing, and image correction processing, it is possible to improve diagnosis accuracy based on the analysis result of the dynamic image.

In addition, the radiation detection unit 13, the imaging console 2, or the diagnostic console 3 may have a function of performing dynamic analysis by excluding or correcting missing pixels as a preprocessing function for feature amount analysis. preferable.
When analyzing a moving image, various statistical values of pixel value groups in the ROI block, such as an average value, maximum value, minimum value, mode value, or median value, may be obtained. If an abnormal pixel value exists, various statistical values in the ROI block become abnormal values, and a correct dynamic image analysis result may not be obtained. Therefore, the radiation detection unit 13, the imaging console 2, or the diagnostic console 3 detects which pixel value is an abnormal pixel before or during imaging, and performs an abnormal operation based on the detected abnormal pixel information. It is preferable to have a function of performing image correction processing for correcting pixels. Alternatively, when calculating various statistical values of the pixel value group in the ROI block to be performed when analyzing the moving image, only the abnormal pixel value is excluded based on the abnormal pixel information detected above, and then the various values in the ROI block. It is preferable to have a function of performing an image analysis process for calculating a statistical value. As a means for detecting where an abnormal pixel is, for example, a pixel value of a dark image may be derived by using a statistical value such as a standard deviation regarding a tendency of a spatial or temporal pixel value change.
By mounting such image correction processing and image analysis processing, it is possible to improve the diagnostic accuracy based on the analysis result of the dynamic image.

Moreover, it is preferable that the radiation detection unit 13, the imaging console 2, or the diagnostic console 3 has a function of correcting an image based on image quality information of the radiation imaging system as a preprocessing function for feature amount analysis.
When trying to compare the analysis results of dynamic images acquired by radiation imaging systems having different image quality characteristics, for example, DQE (Detective Quantum Efficiency) and MTF (Modulation Transfer Function) of the radiation imaging systems that originally acquired the images. In some cases, the analysis results of dynamic images cannot be compared correctly because of different image quality characteristics. Therefore, the radiation detection unit 13, the imaging console 2, or the diagnostic console 3 is an image that corrects an image based on image quality information such as DQE or MTF of the radiation detection unit 13 or system MTF of the radiation imaging system. It preferably has a function of performing a correction process.
By mounting such an image correction processing function, it is possible to improve diagnostic accuracy based on the analysis result of dynamic images acquired by radiation imaging systems having different image quality characteristics.

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

100 chest image display system 1 imaging device 11 radiation source 12 radiation irradiation control device 13 radiation detection unit 14 reading control device 2 imaging console 21 control unit 22 storage unit 23 operation unit 24 display unit 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 (4)

Photographing means for obtaining a dynamic image by photographing the dynamics of the chest;
Analyzing the dynamics based on the dynamic image acquired by the photographing unit, and generating an analysis result image consisting of a plurality of frames indicating the dynamic analysis results;
A region dividing means for dividing each frame of the analysis result image into a plurality of regions corresponding to the plurality of frames;
Generating means for generating a moving image for display in which frames to be displayed in the respective regions are shifted so that phases of analysis results in the plurality of regions match;
Display means for displaying the display moving image generated by the generating means,
A chest image display system. A signal waveform of the value of the analysis result is generated for each of the plurality of regions divided by the region dividing unit, and at least one of the maximum point, the minimum point, the intermediate point, and the positive / negative sign of the generated waveform is switched. An extraction means for extracting a frame corresponding to the feature point;
The generating means calculates a frame shift amount for each of the regions so that the frames of the same feature points extracted from each of the plurality of regions are displayed at the same timing, and sets the frames to be displayed in the respective regions. The chest image display system according to claim 1, wherein the display moving image is generated based on the calculated shift amount. The chest image display system according to claim 1, wherein the display unit displays the analysis result image generated by the analysis unit and the display moving image generated by the generation unit side by side. Analyzing means for analyzing the dynamics based on a dynamic image obtained by photographing the dynamics of the chest, and generating an analysis result image consisting of a plurality of frames indicating the dynamic analysis result;
A region dividing means for dividing each frame of the analysis result image into a plurality of regions corresponding to the plurality of frames;
Generating means for generating a moving image for display in which frames to be displayed in the respective regions are shifted so that phases of analysis results in the plurality of regions match;
Display means for displaying the display moving image generated by the generating means,
An image processing apparatus comprising: