JP2009273603A - Dynamic image capturing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To narrow a radiation irradiation field to the region of an inspection target part even for the inspection target part whose position and size can not be recognized from the appearance, and to suppress the exposure of a subject to a necessary minimum. <P>SOLUTION: The control part 21 of a console 2 for image capturing controls an image capturing device 1, captures images at least at such timing that the size of the inspection target part becomes maximum before the main image capturing of dynamic image capturing to acquire image data, extracts an image region when the inspection target part becomes maximum from the acquired image data, calculates the position of a radiation source 111 for limiting the radiation irradiation field to the inspection target part and a radiation irradiation field size on the basis of the extracted region of the inspection target part, and sets them to the radiation irradiation controller 12 of the image capturing device 1. The radiation irradiation controller 12 adjusts the position of the radiation source 111 and the opening range of an irradiation field diaphragm 112 on the basis of the position of the radiation source 111 and the radiation irradiation field size that are set, and performs main image capturing corresponding to control from a control part 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a dynamic image capturing system.

  In the medical field, interpretation diagnosis is performed by a doctor using an image obtained by radiographing a region to be examined. In radiography, in order to minimize the exposure dose of a patient as a subject, radiation is irradiated only to a region of interest by adjusting an irradiation field stop attached to the front surface of the radiation source.

The adjustment of the irradiation field stop is generally performed by a radiographer, and the radiographer adjusts the radiation field based on the general view of the patient from the viewpoint of the patient. In addition, for example, a technique for controlling a radiation source and an irradiation field stop based on input parameters has been proposed (see, for example, Patent Document 1).
JP 2002-204794 A

  By the way, in recent years, in contrast to conventional radiographic still image photography and diagnosis using a film / screen or photostimulable phosphor plate, a dynamic image of a site to be examined using a semiconductor image sensor such as an FPD (flat panel detector) Attempts have been made to take images and apply them to diagnosis. More 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 quickness of the read / erase response of the image data of the semiconductor image sensor. Take multiple shots per second to capture the dynamics of the area to be examined. By sequentially displaying a series of a plurality of images acquired by imaging, a doctor can recognize a series of movements of a region to be examined.

  An example of a part to be imaged dynamically is a heart. However, there is a problem that a site such as the heart where it is difficult to grasp the approximate position from the appearance of the patient cannot be narrowed down to the radiation field accurately.

  An object of the present invention is to narrow down the radiation field to the region of the inspection target region even if it is the inspection target region whose position and size cannot be grasped from the appearance, and to minimize the exposure of the subject.

In order to solve the above-mentioned problem, the invention described in claim 1
A radiation source that irradiates radiation to a region to be examined in the human body, an irradiation field stop that is disposed in front of the radiation irradiation direction to limit the radiation field, and detects radiation from the radiation source that has passed through the region to be examined A dynamic image for performing dynamic imaging for obtaining a plurality of image data indicating the dynamics of the examination target region by continuously imaging the examination target region a plurality of times by the imaging unit. A shooting system,
Before the dynamic imaging, the imaging unit is allowed to perform imaging at least when the size of the examination target part is maximized to acquire image data, and the examination target part is determined to be maximum from the acquired image data. The image area is extracted, and the position of the radiation source and the radiation field size for limiting the radiation field to the examination target part are calculated based on the extracted region of the examination target part. A control unit for setting in the photographing unit;
The imaging unit adjusts the position of the radiation source and the aperture range of the irradiation field stop at the time of the dynamic imaging based on the position of the radiation source and the size of the irradiation field set by the control unit, and performs dynamic imaging. Do.

The invention according to claim 2 is the invention according to claim 1,
A cycle detection unit for detecting a dynamic cycle of the examination target site;
The control unit determines a timing when the size of the examination target portion is maximized based on a detection result by the cycle detection unit, and causes the imaging unit to perform imaging.

The invention according to claim 3 is the invention according to claim 1 or 2,
The site to be examined is a heart,
Prior to the dynamic imaging, the control unit acquires image data by performing imaging at a timing when the size of the ventricle is maximized and a timing when the size of the atrium is maximized. A heart region is extracted from each of the acquired image data, and the position of the radiation source and the radiation field size are calculated based on a region obtained by superimposing the extracted heart regions.

  According to the present invention, the radiation field can be narrowed down to the region of the inspection target region even if it is the inspection target region whose position and size cannot be grasped from the appearance, and the exposure of the subject can be suppressed to the minimum necessary.

(Configuration of dynamic image capturing system 100)
First, the configuration will be described.
FIG. 1 shows the overall configuration of a dynamic image capturing system 100 in the present embodiment.
As shown in FIG. 1, in the dynamic image capturing system 100, an image capturing apparatus 1 and an image capturing console 2 are connected by a communication cable or the like, and the image capturing console 2 and the diagnosis console 3 are connected to a LAN (Local Area Network). The communication network N is connected and configured.

(Configuration of the photographing apparatus 1)
The imaging device 1 is an imaging unit that images the dynamics of a human body having a periodicity (cycle), such as morphological changes in lung expansion and contraction associated with respiration, heart pulsation, and the like. The dynamic imaging is performed by continuously irradiating the examination target site with radiation and acquiring 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 generator 11, a radiation irradiation controller 12, a radiation detector 13, a reading controller 14, a cycle detection sensor 15, a cycle detector 16, and the like. . 2A and 2B show the positional relationship among the radiation generator 11, the subject M, and the radiation detector 13 during dynamic imaging. FIG. 2A is a diagram schematically showing the radiation generator 11 and the radiation detector 13 from the side, and FIG. 2B is a diagram schematically showing the radiation generator 11 and the radiation detector 13 from the top.

The radiation generator 11 includes a radiation source 111 and an irradiation field stop 112, as shown in FIG. 2A. The radiation source 111 is a radiation tube and irradiates the subject M with radiation (X-rays) under the control of the radiation irradiation control device 12. The irradiation field stop 112 is provided at the radiation outlet of the radiation generator 11, and is driven by a driving unit such as a motor (not shown) controlled by the radiation irradiation control device 12 to open and close the radiation in the radiation detection unit 13. Adjust the field.
The radiation generator 11 is supported on the support base shaft 113 via the support shaft 114. The support base shaft 113 is driven by a drive unit such as a motor (not shown) controlled by the radiation irradiation control device 12 to move up and down, and the height of the radiation generator 11 (the head of the subject M is increased) by the lift of the support base shaft 113. -The position in the foot direction) can be changed. Further, the support shaft 114 is driven by a drive unit such as a motor (not shown) controlled by the radiation irradiation control device 12 to move in the left-right direction relative to the support base shaft 113 (the head of the subject M on the radiation incident surface of the radiation detection unit 13- It is slidable in a direction perpendicular to the foot direction (indicated by an arrow A in FIG. 2B), and the horizontal position of the radiation generator 11, that is, the radiation source 111 can be changed by the horizontal movement of the support shaft 114. It is configured.

The radiation irradiation control device 12 is connected to the imaging console 2 and controls the radiation generator 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. Initial field size, etc. The pulse rate is the number of times of radiation irradiation per unit time (here, per second) and coincides with a 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.
Further, the radiation irradiation control device 12 raises and lowers the support base 113 based on the position information of the radiation source 111 (the height from the floor and the left and right positions with reference to the support base 113) input from the imaging console 2. The position of the radiation source 111 is adjusted by moving the support shaft 114 in the left-right direction. Further, the radiation irradiation control device 12 opens and closes the irradiation field stop 112 based on the information of the radiation field size input from the imaging console 2.

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 generator 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 electricity. A plurality of pixels that are converted into signals and accumulated are arranged in a matrix. Each pixel includes a switching unit such as a TFT (Thin Film Transistor).
As illustrated in FIG. 2A, the radiation detection unit 13 is disposed at a position facing the radiation generation apparatus 11 with the subject M interposed therebetween. The radiation detection unit 13 is supported so as to be able to move up and down along the support base 131, and the position of the radiation detection unit 13 (from the floor surface) according to the height of the subject M by the operation of a foot switch (not shown) by the imaging technician. Height) can be adjusted.

The reading control device 14 is connected to the imaging console 2, controls the switching unit of each pixel of the radiation detection unit 13 based on the image reading conditions input from the imaging console 2, and accumulates in each pixel. Image data is acquired by switching the reading of the electric signal and reading the electric signal accumulated in the radiation detection unit 13. Then, the acquired image data is output to the imaging 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 unit time (here, 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.
The pulse interval and frame interval are obtained from the pulse rate and frame rate.

  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.

The cycle detection sensor 15 detects the state of the inspection target part of the subject M and outputs detection information to the cycle detection device 16. As the cycle detection sensor 15, for example, when the site to be examined is lung (ventilation), a respiratory monitor belt, a CCD (Charge Coupled Device) camera, an optical camera, a spirometer, or the like can be applied. Further, when the examination target site is the heart, an electrocardiograph or the like can be applied.

Based on the detection information input by the cycle detection sensor 15, the cycle detection device 16 counts the number of cycles of the dynamics of the site to be examined (the number of cycles per unit time. For example, if the site to be examined is lung (ventilation), breathing Number (times / second), heart rate in the case of heart (times / second), and the current state of the region to be examined are detected in one cycle, and the detection results (cycle information) are taken. To the control unit 21 of the console 2.
For example, when the examination target site is lung (ventilation), the cycle detection device 16 converts the lung state from inspiration to expiration by the cycle detection sensor 15 (respiration monitor belt, CCD camera, optical camera, spirometer, etc.). The timing at which detection information indicating a point is input is taken as the base point of one cycle, and the period up to the timing at which this state is detected next is recognized as one cycle.
In addition, when the examination target site is a heart (including blood flow), the cycle detection device 16 uses the timing at which the R wave is input by the cycle detection sensor 15 (electrocardiograph or the like) as a base point, and then the R wave The period up to the detected timing is recognized as one cycle.
The number of cycles recognized per second is detected as the number of cycles.

(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 radiation image reading operations by the imaging apparatus 1, and also captures image data acquired by the imaging apparatus 1. It is a device that displays to confirm whether the image is suitable for the confirmation of positioning by means of or the 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, a communication unit 25, and the like, 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 out various processing programs such as a system program stored in the storage unit 22 and a photographing control processing program in response to an operation of the operation unit 23, expands them in the RAM, and expands them. The operation of each part of the imaging console 2 and the radiation irradiation operation and the reading operation of the imaging apparatus 1 are centrally controlled according to the program. A timer (not shown) is connected to the control unit 21.

  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 shooting control processing described later. In addition, the storage unit 22 stores imaging conditions (radiation irradiation conditions and image reading conditions) corresponding to the examination target part in association with the part name of each examination target part that can be an imaging target. 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 router, a TA (Terminal Adapter), and the like, and controls data transmission / reception with each device connected to the communication network N.

(Configuration of diagnostic console 3)
The diagnostic console 3 is a device for displaying image data transmitted from the imaging console and performing 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, a communication unit 35, and the like, 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 develops them in the RAM, and each part of the diagnostic console 3 according to the developed programs. Centralized control of the operation.

  The storage unit 32 is configured by a nonvolatile semiconductor memory, a hard disk, or the like. The storage unit 32 stores various programs executed by the control unit 31 and data such as parameters necessary for execution of processing by the programs 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 router, a TA, and the like, and controls data transmission / reception with each device connected to the communication network N.

(Operation of the dynamic image capturing system 100)
Next, the operation in the dynamic image capturing system 100 will be described.
FIG. 3 shows the flow of processing in the imaging console 2 and the imaging apparatus 1 during dynamic imaging.

  First, the operation unit 23 is operated by the imaging engineer, and input of patient information (name, height, weight, age, sex, etc. of the subject M) of the subject M, designation input of the examination target region, and the like are performed (step S1). In the following description, it is assumed that “heart” has been designated by the photographer.

  Next, the control unit 21 of the imaging console 2 reads the radiation irradiation condition corresponding to the designated inspection target region from the storage unit 22 and sets the radiation irradiation condition in the radiation irradiation control device 12. Is read from the storage unit 22 and set in the reading control device 14 (step S2).

  The set radiation irradiation conditions include the initial irradiation field size. In the imaging apparatus 1, the initial irradiation field in which the radiation irradiation field in the radiation detection unit 13 is set under the control of the radiation irradiation control device 12. The irradiation field stop 112 is adjusted to be the size (step S3).

  When the imaging engineer designates the examination target part on the imaging console 2, the imaging engineer performs positioning on the imaging apparatus 1 (step S4). That is, the patient who is the subject M is placed in front of the radiation detection unit 13 of the imaging apparatus 1, and the height of the radiation detection unit 13 is adjusted by an operation of a foot switch (not shown). Information on the height of the radiation detection unit 13 is transmitted to the radiation irradiation control device 12 via the reading control device 14, and the radiation source 111 is centered on the radiation incident surface of the radiation detection unit 13 by the control of the radiation irradiation control device 12. The position of the radiation generator 11 is moved so as to face the position.

  In the photographing console 2, an input of a photographing start instruction by operating the operation unit 23 is awaited. When a photographing start instruction is input by the operating unit 23 (Step S <b> 5; YES), the pre-shooting control is performed by the control unit 21. Is performed (step S6), and in the photographing apparatus 1, pre-photographing is performed according to the control of the control unit 21 (step S7). The pre-shooting is a shooting performed before the main shooting of the dynamic shooting. In the present embodiment, pre-imaging is performed in order to acquire image data for image analysis for adjusting the radiation field.

  In pre-imaging, first, the control unit 21 outputs a cycle detection start instruction to the cycle detection device 16, and the cycle detection sensor 15 and the cycle detection device 16 start cycle detection of the dynamics of the examination target portion of the subject M. When the cycle detection device 16 detects that the dynamics of the examination target site are in a predetermined state, the control unit 21 determines that the size (size) of the examination target site is maximized. Then, an imaging start instruction is output to the radiation irradiation control device 12 and the reading control device 14, and radiation is emitted to perform imaging. For example, when the examination target site is the heart and the cycle detection sensor 15 is an electrocardiograph, the control unit 21 determines that the ventricle is in the maximum state when the cycle detection device 16 detects the timing when the R wave is input. It is judged that it has become, and photography is carried out. As a result, it is possible to acquire an image at a timing at which the ventricle is maximized. Further, when the timing at which the T wave falls is detected by the cycle detection device 16, the control unit 21 determines that the atrium is in the maximum state, and imaging is performed. Thereby, it is possible to acquire an image at a timing at which the atrium is maximized. In the present embodiment, as will be described later, an image acquired by pre-imaging is only used for region extraction of a region to be inspected, so by lowering the tube current time product for one frame than at the time of actual imaging, It is possible to reduce the exposure of the subject M.

  Image data acquired by pre-shooting is transmitted to the shooting console 2 (step S8). In the imaging console 2, the control unit 21 extracts the region of the examination target region from the image data acquired by the pre-imaging (step S9).

For example, when the examination target site is the heart, the extraction of the heart region in the image data acquired by imaging can be performed by the following processes (1) to (4).
(1) Extract a lung field region.
Since the lung field around the heart region has a large amount of radiation (X-ray) transmission, the signal value is higher than the surrounding region, and the signal value is lower in the heart region than the lung field. Therefore, first, 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.
(2) A density histogram in a circumscribed rectangular region of the lung field region is created, a threshold value is obtained by a discriminant analysis method or the like, and a region having a signal lower than the threshold value is extracted as a cardiac candidate region.
(3) Edge detection is performed within a candidate region of the heart, and edge points having a predetermined size or more are extracted.
(4) Template matching is performed with a heart-shaped template on the edge image composed of the extracted edge point and the boundary line of the cardiac candidate region, and the template region at the position where the correlation value is maximized is set as the heart region. recognize.
It should be noted that the heart region can be specified more accurately by calculating the correlation value in the template that is relatively enlarged / reduced with respect to the candidate region of the heart and obtaining the position where the correlation value is maximized.

  Next, the control unit 21 determines the radiation field size and the position of the radiation source 111 in the main imaging so as to limit the radiation field to the examination target region based on the extracted region of the examination target region ( Step S10). In step S10, specifically, a circumscribed rectangle (circumscribed circle) of the extracted region to be examined is calculated, and the center position and the size of the circumscribed rectangle are calculated. Then, the calculated center position is determined as the position of the radiation source 111 in the main imaging, and the calculated circumscribed rectangle size + predetermined margin (for example, α% expansion with respect to the center position reference) is determined as the radiation field size in the main imaging. When the examination site is the heart, an area where the heart region extracted from each of the image data acquired at the timing when the ventricle is maximized and the image data acquired at the timing when the atrium is maximized is superposed. The circumscribed rectangle (circumscribed circle) of the region where the heart region is overlapped is calculated, the center position is the position of the radiation source 111 in the main imaging, the size of the circumscribed rectangle + a predetermined margin (for example, α% with respect to the center position reference) (Expansion) is determined as the radiation field size for the actual radiography.

  The radiation irradiation field size and the position information of the radiation source 111 in the main imaging determined in step S10 are set in the radiation irradiation control device 12 (step S11). In the imaging apparatus 1, the irradiation field stop 112 is adjusted by the control of the radiation control unit 12 so that the radiation field in the radiation detection unit 13 becomes the set radiation field size. Further, the height and / or the horizontal position of the radiation generator 11 is changed based on the position information of the radiation source 111 under the control of the radiation irradiation control device 12 (step S12).

  FIG. 4 schematically shows an initial irradiation field (indicated by F1 in FIG. 4) and a radiation irradiation field (indicated by F2 in FIG. 4) adjusted based on pre-imaging when the examination target site is the heart. The initial irradiation field F1 is a radiation irradiation field adjusted based on the initial irradiation field size, and is a range including the entire lung field. Image analysis is performed using image data acquired by pre-imaging, a heart region that cannot be determined from the appearance of the subject M is specified, and the adjustment of the irradiation field stop 112 and the position of the radiation source 111 are adjusted based on the specified heart region. As a result, the irradiation field is narrowed down to the irradiation field F2, that is, the heart region H. In this way, it is possible to reduce the unnecessary exposure other than the inspection target part by specifying the inspection target part that cannot be grasped from the appearance of the subject M by image analysis based on the pre-photographing and narrowing the radiation irradiation field to the minimum necessary. It becomes possible.

  After setting the radiation field size and the position of the radiation source 111, the imaging console 2 performs the main imaging control by the control unit 21 (step S <b> 13), and the imaging apparatus 1 performs the main imaging according to the control of the control unit 21. Implemented (step S14).

  In this radiography, the cycle detection device 16 is in a predetermined state (for example, when the cycle detection sensor 15 is an electrocardiograph and the R wave is input) in a predetermined state. When detected, the control unit 21 outputs a main imaging start instruction to the radiation irradiation control device 12 and the reading control device 14. In the imaging device 1, radiation is emitted by the radiation generation device 11 at the pulse interval set in the radiation irradiation control device 12, and image data (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.

  The image data of the frame image acquired by shooting is sequentially transmitted to the shooting console 2 (step S15). In the photographing console 2, the control unit 21 stores the image data in the storage unit 22 in association with the number indicating the photographing order and displays the image data on the display unit 24 (step S16). 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 judgment result indicating photographing OK is input by a predetermined operation of the operation unit 23 (step S17; YES), a series of image data obtained by dynamic photographing, that is, a series of frame images is respectively input by the control unit 21. Identification information for identifying a dynamic image, information such as patient information, examination site, radiation irradiation conditions, image reading conditions, imaging order number, cycle information, etc. are attached (for example, image data in DICOM format) And is transmitted to the diagnostic console 3 via the communication unit 25 (step S18). 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 S17; NO), a series of image data stored in the storage unit 22 is deleted by the control unit 21 (step S19). ), This process ends. In the imaging apparatus 1, when imaging is completed, the radiation source 111 is returned to a position facing the center position of the radiation incident surface of the radiation detection unit 13.

  Note that the control unit 21 recognizes the region of the examination target region from the frame image acquired in the main imaging, and when the distance between the recognized region and the radiation field end becomes a predetermined value or less, a new radiation field is obtained. The size may be determined and control may be performed to change the radiation field size during the main imaging, or an instruction to stop the patient who is the subject M may be displayed or output as audio. In addition, it is preferable that the frame image acquired in the main imaging stores only the data in the radiation irradiation field and deletes other unnecessary data areas.

  In the diagnostic console 3, when a series of image data continuously captured from the imaging console 2 is received by the communication unit 35, the control unit 31 stores the received image data in the storage unit 32.

  In the diagnostic console 3, when an identification ID or the like is input by the operation unit 33 and image data (dynamic image) to be diagnosed is designated, a series of images of the dynamic image designated from the storage unit 32 by the control unit 31. Data is read out. And it displays for the diagnostic interpretation of a doctor by displaying on the display part 34 sequentially.

  As described above, according to the dynamic image capturing system 100, the control unit 21 of the imaging console 2 controls the imaging apparatus 1 and at least the timing at which the size of the examination target region is maximized before the main imaging of the dynamic imaging. To obtain image data, extract an image region when the inspection target region is maximized from the acquired image data, and based on the extracted region of the inspection target region, The position of the radiation source 111 for limiting the radiation field and the radiation field size are calculated and set in the radiation control device 12 of the imaging apparatus 1. The radiation irradiation control device 12 adjusts the position of the radiation source 111 and the opening range of the irradiation field stop 112 based on the set position and radiation field size of the radiation source 111, and performs the main control according to the control from the control unit 21. Take a picture.

  Therefore, even if it is an inspection target part whose position and size cannot be grasped from the appearance of the subject M, it is possible to narrow down the radiation irradiation field to the region of the inspection target part and to suppress the exposure of the subject M to the minimum necessary.

  In addition, based on the detection result by the cycle detection device 16, the control unit 21 determines the timing when the size of the examination target part is maximized, and performs pre-imaging at that timing, so that the minimum necessary pre-imaging is performed. Thus, it is possible to specify the region of the inspection target region.

  Further, when the examination target site is a heart, pre-imaging is performed at the timing when the size of the ventricle is maximized and the timing when the size of the atrium is maximized, and image data is acquired. Since the heart region is extracted from each of the image data and the position of the radiation source 111 and the radiation field size are calculated based on the region obtained by superimposing the extracted heart regions, the timing when either the ventricle or the atrium is maximized But it is possible to fit the heart in the radiation field.

In addition, the description in this Embodiment mentioned above is an example of the suitable dynamic image imaging system which concerns on this invention, and is not limited to this.
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. As another computer-readable medium, a portable recording medium such as a CD-ROM can be applied. Further, 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 apparatus constituting the dynamic image capturing system 100 can be changed as appropriate without departing from the spirit of the present invention.

It is a figure which shows the example of whole structure of the dynamic image imaging system in embodiment of this invention. It is the figure which showed typically the radiation generator and the radiation detection part from the side surface. It is the figure which showed typically the radiation generator and the radiation detection part from the upper surface. It is a flowchart which shows the flow of a process in the imaging | photography console and imaging | photography apparatus at the time of dynamic imaging | photography. It is a figure which shows typically the irradiation field adjusted based on the initial irradiation field at the time of making a test | inspection site | part into the heart, and pre imaging | photography.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Dynamic image radiography system 1 Imaging device 11 Radiation generation device 111 Radiation source 112 Irradiation field stop 113 Support base 114 Support shaft 12 Radiation irradiation control device 13 Radiation detection part 131 Support base 14 Reading control device 15 Cycle detection sensor 16 Cycle detection device 2 Imaging console 21 Control unit 22 Storage unit 23 Operation unit 24 Display unit 25 Communication unit 26 Bus 3 Diagnosis console 31 Control unit 32 Storage unit 33 Operation unit 34 Display unit 35 Communication unit 36 Bus

Claims (3)

A radiation source that irradiates radiation to a region to be examined in the human body, an irradiation field stop that is disposed in front of the radiation irradiation direction to limit the radiation field, and detects radiation from the radiation source that has passed through the region to be examined A dynamic image for performing dynamic imaging for obtaining a plurality of image data indicating the dynamics of the examination target region by continuously imaging the examination target region a plurality of times by the imaging unit. A shooting system,
Before the dynamic imaging, the imaging unit is allowed to perform imaging at least when the size of the examination target part is maximized to acquire image data, and the examination target part is determined to be maximum from the acquired image data. The image area is extracted, and the position of the radiation source and the radiation field size for limiting the radiation field to the examination target part are calculated based on the extracted region of the examination target part. A control unit for setting in the photographing unit;
The imaging unit adjusts the position of the radiation source and the aperture range of the irradiation field stop at the time of the dynamic imaging based on the position of the radiation source and the size of the irradiation field set by the control unit, and performs dynamic imaging. Dynamic imaging system to perform. A cycle detection unit for detecting a dynamic cycle of the examination target site;
2. The dynamic image capturing according to claim 1, wherein the control unit determines a timing when the size of the examination target portion is maximized based on a detection result by the cycle detection unit, and causes the imaging unit to perform imaging. system. The site to be examined is a heart,
Prior to the dynamic imaging, the control unit acquires image data by performing imaging at a timing when the size of the ventricle is maximized and a timing when the size of the atrium is maximized. The heart region is extracted from each of the acquired image data, and the position of the radiation source and the radiation field size are calculated based on a region obtained by superimposing the extracted heart regions. Dynamic imaging system.

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