IMAGING SUPPORT APPARATUS, OPERATION METHOD OF IMAGING SUPPORT APPARATUS, AND OPERATION PROGRAM OF IMAGING SUPPORT APPARATUS

A first acquisition unit acquires an optical image in which both an electronic cassette in which a detection panel for detecting radiation is built in a portable housing and a subject facing radiography using the electronic cassette are shown, from a camera. A first demarcation unit demarcates a detection region of the radiation by the detection panel, the detection region being determined in accordance with a position of the electronic cassette, in the optical image. A second demarcation unit demarcates an imaging region which is a region to be imaged in the radiography, the imaging region being determined in accordance with a position of the subject, in the optical image. A display controller performs control of displaying a frame indicating the detection region and a frame indicating the imaging region on a touch panel display in a manner of being superimposed on the optical image.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2022-030381, filed on Feb. 28, 2022. The above application is hereby expressly incorporated by reference, in its entirety, into the present application.

BACKGROUND

1. Technical Field

The technology of the present disclosure relates to an imaging support apparatus, an operation method of an imaging support apparatus, and an operation program of an imaging support apparatus.

2. Description of the Related Art

There is known an electronic cassette in which a detection panel for detecting radiation is built in a portable housing. The electronic cassette is used in a state of being accommodated in a holder of an imaging table installed in a radiography room, and is mainly used as a single unit in a state of being removed from the holder by taking advantage of its mobility. For example, the electronic cassette is used in a case of round-visit imaging in which the radiography is performed by traveling around a hospital room in which there is a patient who cannot go to the radiography room. In addition, the electronic cassette may be taken out of a medical facility for the radiography of an elderly person undergoing medical treatment at home or a suddenly ill person due to an accident, disaster, or the like.

JP2020-192440A discloses the technology in which an optical image in which both an electronic cassette and a subject facing radiography using the electronic cassette are shown is acquired from a camera, a position of the electronic cassette in the optical image is detected, and a frame indicating the electronic cassette based on the detected position is displayed on a display in a manner of being superimposed on the optical image. In a tenth embodiment, an aspect is described in which, in a case in which the subject lies down on a bed is subjected to the radiography, a frame indicating a recommended installation position (referred to as a recommended position in JP2020-192440A) of the electronic cassette on the bed is displayed on the display in a manner of being superimposed on the optical image together with the frame indicating the electronic cassette.

SUMMARY

In the radiography using the electronic cassette, the installation position of the electronic cassette can be freely set. Therefore, there is a concern that a situation occurs in which an error is made in the installation position of the electronic cassette with respect to the subject and the imaging is performed in a state in which the electronic cassette does not cover an imaging region to be imaged in the radiography.

In JP2020-192440A, in order to avoid a situation in which the imaging is performed in a state in which the imaging region is not covered by the electronic cassette, the frame indicating the recommended position is displayed in a manner of being superimposed on the optical image. However, JP2020-192440A does not discloses how the recommended position is set, and also how the recommended position is related to the imaging region. Therefore, there is insufficient solution as a solution for avoiding the situation in which the imaging is performed in a state in which the imaging region is not covered by the electronic cassette.

One embodiment according to the technology of the present disclosure provides an imaging support apparatus, an operation method of an imaging support apparatus, and an operation program of an imaging support apparatus capable of contributing to more accurate positioning of the electronic cassette with respect to the subject.

The present disclosure relates to an imaging support apparatus comprising a processor, in which the processor acquires an optical image in which both an electronic cassette in which a detection panel for detecting radiation is built in a portable housing and a subject facing radiography using the electronic cassette are shown, from a camera, demarcates a detection region of the radiation by the detection panel, the detection region being determined in accordance with a position of the electronic cassette, in the optical image, demarcates an imaging region which is a region to be imaged in the radiography, the imaging region being determined in accordance with a position of the subject, in the optical image, and performs control of displaying an indicator indicating the detection region and an indicator indicating the imaging region on a display in a manner of being superimposed on the optical image.

It is preferable that the processor demarcate the detection region based on a detection result of a position detection sensor that detects the position of the electronic cassette.

It is preferable that the processor extract a portion of interest of the subject included in the optical image, and demarcate the imaging region based on the portion of interest.

It is preferable that, in a state in which the subject lies down on a bed, in a case in which the electronic cassette is inserted between the subject and the bed and the radiography is performed, the processor operate an optical display that displays light for position adjustment of the electronic cassette on a side portion along a long side direction of the bed to display an insertion position of the electronic cassette corresponding to the imaging region.

The present disclosure relates to an operation method of an imaging support apparatus, the method comprising acquiring an optical image in which both an electronic cassette in which a detection panel for detecting radiation is built in a portable housing and a subject facing radiography using the electronic cassette are shown, from a camera, demarcating a detection region of the radiation by the detection panel, the detection region being determined in accordance with a position of the electronic cassette, in the optical image, demarcating an imaging region which is a region to be imaged in the radiography, the imaging region being determined in accordance with a position of the subject, in the optical image, and performing control of displaying an indicator indicating the detection region and an indicator indicating the imaging region on a display in a manner of being superimposed on the optical image.

The present disclosure relates to an operation program of an imaging support apparatus, the program causing a computer to execute a process comprising acquiring an optical image in which both an electronic cassette in which a detection panel for detecting radiation is built in a portable housing and a subject facing radiography using the electronic cassette are shown, from a camera, demarcating a detection region of the radiation by the detection panel, the detection region being determined in accordance with a position of the electronic cassette, in the optical image, demarcating an imaging region which is a region to be imaged in the radiography, the imaging region being determined in accordance with a position of the subject, in the optical image, and performing control of displaying an indicator indicating the detection region and an indicator indicating the imaging region on a display in a manner of being superimposed on the optical image.

According to the technology of the present disclosure, it is possible to provide the imaging support apparatus, the operation method of the imaging support apparatus, and the operation program of the imaging support apparatus capable of contributing to more accurate positioning of the electronic cassette with respect to the subject.

DETAILED DESCRIPTION

First Embodiment

As shown inFIG.1as an example, a radiography system2is a system that performs radiography of a subject H by using radiation R, such as X-rays and γ-rays, and includes a mobile radiation generation device10, an electronic cassette11, a console12, and a camera13. The mobile radiation generation device10includes a carriage unit14, a radiation source15, and an irradiation switch16. The carriage unit14is a rectangular parallelepiped block, and four wheels17are attached to the front, rear, left, and right sides below the block. With the wheels17, the mobile radiation generation device10can be used for round-visit imaging in which the radiography of the subject H is performed while traveling around a hospital room in a medical facility. Therefore, the mobile radiation generation device10is also referred to as a round-visit vehicle.

FIG.1shows a state in which chest portion front surface imaging of the subject H lying down on a bed18in the hospital room is performed. In this case, the electronic cassette11is inserted between the subject H and the bed18by an operator OP, such as a medical radiologist. That is, in the present example, the electronic cassette11is not used in a state of being accommodated in a holder of an imaging table installed in a radiography room, and is removed from the holder and used as a single unit. The radiography performed by using the electronic cassette11as a single unit in this way is called free imaging. It should be noted that the mobile radiation generation device10can also be brought into a surgery room and used during the surgery. In addition, the mobile radiation generation device10can also be brought to an outdoor disaster site or the like and used for emergency use.

The radiation source15is attached to the carriage unit14via a first arm19and a second arm20. The first arm19extends in a vertical direction from the center of a front portion of an upper surface of the carriage unit14. The first arm19can be expanded and contracted in the vertical direction. Along with the expansion and contraction of the first arm19, a height position of the radiation source15is changed. In addition, the first arm19is rotatable with respect to the carriage unit14with a vertical axis as a rotation axis.

The second arm20extends in a horizontal direction from a distal end of the first arm19. The second arm20can be expanded and contracted in the horizontal direction. Along with the expansion and contraction of the second arm20, a horizontal position of the radiation source15is changed. The expansion/contraction positions of the first arm19and the second arm20are detected by a linear encoder, for example.

The radiation source15includes a radiation tube21and an irradiation field limiter22. The radiation tube21is provided with a filament, a target, a grid electrode, and the like (all of which are not shown). A voltage is applied between the filament, which is a cathode, and the target, which is an anode. The voltage applied between the filament and the target is called a tube voltage. The filament releases thermoelectrons corresponding to the applied tube voltage toward the target. The target emits the radiation R by collision of the thermoelectrons from the filament. The grid electrode is disposed between the filament and the target. The grid electrode changes a flow rate of the thermoelectrons from the filament toward the target in accordance with the applied voltage. The flow rate of the thermoelectrons from the filament toward the target is called a tube current.

The irradiation field limiter22is also called a collimeter and limits an irradiation field of the radiation R emitted from the radiation tube21. The irradiation field limiter22has a configuration in which, for example, four shielding plates, such as lead, which shield the radiation R are disposed on respective sides of the quadrangle and an emission opening of the quadrangle that transmits the radiation R is formed in a central portion. The irradiation field limiter22changes a size of the emission opening by changing a position of each shielding plate, thereby changing the irradiation field of the radiation R.

A radiation source control device23and a tube voltage generator24are built in the carriage unit14. The radiation source control device23is wirelessly connected to the console12in a communicable manner. The radiation source control device23controls an operation of the tube voltage generator24. In addition, the irradiation switch16is connected to the radiation source control device23. The radiation source control device23controls an operation of the radiation source15in response to various instruction signals from the irradiation switch16. The irradiation switch16is operated in a case in which the operator OP instructs the radiation source15to start the irradiation with the radiation R. The irradiation switch16is attachably and detachably attached to the carriage unit14.

An irradiation condition63(seeFIG.5) of the radiation R is set in the radiation source control device23. The irradiation condition63is the tube voltage, the tube current, and the irradiation time of the radiation R applied to the radiation tube21. In a case in which the instruction to start the irradiation with the radiation R is given by the operation of the irradiation switch16, the radiation source control device23operates the tube voltage generator24in accordance with the set irradiation condition63to emit the radiation R from the radiation tube21. The radiation source control device23stops the irradiation with the radiation R from the radiation tube21in a case in which the irradiation time set in the irradiation condition63elapses after the irradiation with the radiation R is started. The tube voltage generator24generates the tube voltage by boosting an input voltage with a transformer. The tube voltage generated by the tube voltage generator24is supplied to the radiation tube21through a voltage cable (not shown).

It should be noted that the irradiation with the radiation R may end by an auto exposure control (AEC) function. The AEC function is a function of detecting the dose of the radiation R during the irradiation with the radiation R, and stopping the irradiation of the radiation R from the radiation tube21at a point in time at which a cumulative dose which is an integrated value of the detected dose, reaches a preset target dose.

A cassette storage portion25and a handle26are provided at a rear portion of the carriage unit14. The cassette storage portion25stores the electronic cassette11. There are a plurality of types of the electronic cassettes11having vertical and horizontal sizes, such as 17 inches×17 inches, 17 inches×14 inches, and 12 inches×10 inches. The cassette storage portion25can store a plurality of the electronic cassettes11having a plurality of types, regardless of the type. In addition, the cassette storage portion25has a function of charging a battery of the stored electronic cassette11.

The handle26is gripped by the operator OP in order to steer the carriage unit14, and thus the mobile radiation generation device10. The operator OP causes the mobile radiation generation device10to travel while gripping the handle26.

The console12is, for example, a tablet terminal and is an example of an “imaging support apparatus” according to the technology of the present disclosure. It should be noted that the console12may be a laptop personal computer or the like.

The camera13is a digital camera which captures a digital optical image40(seeFIG.3). The camera13is attached to the center of a distal end of the irradiation field limiter22of the radiation source15. The camera13is wirelessly connected to the console12in a communicable manner. The camera13images the subject H lying down on the bed18in response to an imaging instruction from the console12. The imaging instruction for the optical image40to the camera13through the console12is, for example, given by the operator OP after the mobile radiation generation device10is brought into the hospital room. The camera13transmits the captured optical image40to the console12. It should be noted that the camera13may be built in the irradiation field limiter22.

As shown inFIG.2as an example, the electronic cassette11includes a portable housing30having a flat box-like shape (rectangular shape in a plan view). The housing30is made of metal or resin having conductivity. Therefore, the housing30also functions as an electromagnetic shield for preventing electromagnetic noise from entering an inside of the electronic cassette11and radiating the electromagnetic noise from the electronic cassette11to an outside. A rectangular plate-shaped radiation transmission plate31that is one size smaller than the housing30is attached to a front surface of the housing30on which the radiation R is incident. The radiation transmission plate31is made of, for example, a carbon material that is lightweight, has high rigidity, and has high radiation transmittance.

An image detection unit32and a circuit unit33are built in the housing30. The image detection unit32is composed of a scintillator34and a detection panel35having substantially the same size as the radiation transmission plate31. The scintillator34and the detection panel35are laminated in an order of the scintillator34and the detection panel35as viewed from a front surface side of the housing30on which the radiation R is incident.

The scintillator34has a phosphor, such as thallium-activated cesium iodide (CsI:Tl) or terbium-activated gadolinium oxysulfide (Gd2O2S:Tb, GOS), and converts the incident radiation R into visible light and releases the visible light. The detection panel35has a configuration in which a plurality of pixels are arranged in a two-dimensional matrix on one thin film transistor (TFT) active matrix substrate. A substantially entire surface of the surface of the detection panel35functions as a detection region DR (seeFIG.4) of the radiation R. The detection panel35accumulates the charge corresponding to the visible light released from the scintillator34in the pixel, converts the charge accumulated in the pixel into an electric signal, and outputs the electric signal. The detection panel35is also called a flat panel detector (FPD).

The circuit unit33controls an operation of the detection panel35. Specifically, in a case in which the irradiation with the radiation R is started, the circuit unit33causes the detection panel35to perform an accumulation operation of accumulating the charge in the pixels. In addition, in a case in which the irradiation with the radiation R ends, the circuit unit33causes the detection panel35to perform a readout operation of reading out the charge accumulated in the pixels as the electric signal. In a case in which the irradiation with the radiation R ends by the AEC function, the circuit unit33causes the detection panel35to perform the readout operation in a case in which the cumulative dose of the radiation R reaches the target dose. The circuit unit33generates a radiation image66based on the electric signal output from the detection panel35.

Two radio wave receivers36are attached to the inside of the housing30at symmetrical positions at the center of the upper and lower sides. The radio wave receiver36is provided to detect a position of the electronic cassette11on the bed18. That is, the radio wave receiver36is an example of a “position detection sensor” according to the technology of the present disclosure.

The scintillator34and the detection panel35may be laminated in an order of the detection panel35and the scintillator34as viewed from the front surface side. In addition, the image detection unit32may be a direct conversion type that directly converts the radiation R into the electric signal instead of an indirect conversion type that converts the radiation R as the visible light by the scintillator34of the present example into the electric signal by the detection panel35.

Although not shown, the housing30includes a battery and an antenna which are built therein. The electronic cassette11can perform wireless communication with the console12by the antenna. In a case in which wireless communication is performed with the console12, the electronic cassette11is driven by electric power from the battery and can be used wirelessly.

FIG.3shows an example of a state in which the camera13images the subject H lying down on the bed18for the chest portion front surface imaging in response to the imaging instruction of the operator OP. In this case, the radiation source15, and thus the camera13, are positioned directly above the chest portion of the subject H. At this position, the camera13has a field of view FOV capable of imaging about ¾ of the bed18, an upper body of the subject H lying down on the bed18, and a part of a lower body up to below the knee. The optical image40captured by the camera13in this way shows about ¾ of the bed18, the upper body of the subject H lying down on the bed18, and a part of the lower body up to below the knee.

Here, the object “shown” in the optical image40includes an object that is present in the optical image40but is covered and hidden by some object. Therefore, the electronic cassette11that is inserted between the subject H and the bed18and is covered and hidden by the subject H can also be referred to as the object “shown” in the optical image40.

As an example, as shown inFIG.4, two radio wave transmitters45are installed by the operator OP at two corners of the bed18on a head portion side of the subject H. The two radio wave transmitters45transmit radio waves RW toward the radio wave receivers36of the electronic cassette11. The radio wave RW has the same intensity in each radio wave transmitter45, but has a different frequency. That is, the radio wave RW has two channels. The radio wave receiver36receives the radio wave RW of each of the two channels. The radio wave receiver36outputs the intensity of the received radio wave RW of the two channels (hereinafter, referred to as the received radio wave intensity) as a detection result46.

The received radio wave intensity is changed in accordance with a distance from the radio wave transmitter45to the radio wave receiver36. Therefore, the distance from the radio wave transmitter45to the radio wave receiver36can be grasped from the received radio wave intensity. In a case in which the distance from the radio wave transmitter45to the radio wave receiver36is grasped, the position of the electronic cassette11on the bed18can also be grasped. In addition, a positional relationship between the radio wave receiver36and four vertexes DRP1, DRP2, DRP3, and DRP4of the detection region DR is known. Therefore, bed detection region information47indicating the positions of the vertexes DRP1to DRP4can be derived from the detection result46. The electronic cassette11transmits the bed detection region information47to the console12.

The bed detection region information47is a bed position coordinate BI_DRP1(x, y) of the vertex DRP1, a bed position coordinate BI_DRP2(x, y) of the vertex DRP2, a bed position coordinate BI_DRP3(x, y) of the vertex DRP3, and a bed position coordinate BI_DRP4(x, y) of the vertex DRP4. The bed position coordinate BI (x, y) is a position coordinate in a case in which, for example, an installation position of the radio wave transmitter45on the left side of the subject H among the two radio wave transmitters45is set as an origin and a direction along a short side of the bed18is set as an x-axis and a direction along a long side of the bed18is set as an y-axis. It should be noted that the bed position coordinate BI (x, y) of a diagonal point of the detection region DR, such as the bed position coordinate BI_DRP1(x, y) and the bed position coordinate BI_DRP4(x, y), may be set as the bed detection region information47.

As shown inFIG.5as an example, the console12comprises a storage55, a memory56, a central processing unit (CPU)57, a communication interface (I/F)58, and a touch panel display59. The storage55, the memory56, the CPU57, the communication I/F58, and the touch panel display59are connected to each other via a busline (not shown). The storage55, the memory56, the CPU57, and the busline are examples of a “computer” according to the technology of the present disclosure.

The storage55is a hard disk drive built in a computer constituting the console12or a hard disk drive connected to the computer through a cable or a network. In the storage55, a control program, such as an operating system, various application programs, various data associated with such programs, and the like are stored. It should be noted that a solid state drive may be used instead of the hard disk drive.

The memory56is a work memory for the CPU57to execute processing. The CPU57loads the program stored in the storage55into the memory56and executes the processing in accordance with the program. As a result, the CPU57controls each unit of the computer in an integrated manner. The CPU57is an example of a “processor” according to the technology of the present disclosure. It should be noted that the memory56may be built in the CPU57.

The communication I/F58controls transmission of various types of information with an external device, such as the electronic cassette11. The touch panel display59displays various screens and receives an operation instruction from the operator OP. The touch panel display59is an example of a “display” according to the technology of the present disclosure.

The CPU57receives an imaging order61from the radiology information system (RIS)60via the communication I/F58. In the imaging order61, a subject identification data (ID) for identifying the subject H, an instruction of an imaging technique by a doctor or the like of a medical department who has issued the imaging order61, and the like are registered. The CPU57displays the imaging order61on the touch panel display59in response to an instruction from the operator OP through the touch panel display59. The operator OP confirms a content of the imaging order61through the touch panel display59.

The CPU57displays a plurality of types of imaging menus62on the touch panel display59in a manner in which a plurality of types of imaging menus62can be selected. The imaging menu62defines an imaging technique in which an imaging part of the subject H, an imaging posture of the subject H, and an imaging direction of the subject H are set as one set, such as “chest portion, decubitus, front surface”. The imaging part includes a head portion, a neck portion, an abdomen portion, a waist portion, a shoulder, an elbow, a hand, a knee, an ankle, and the like, in addition to the chest portion. The imaging posture includes upright, sitting, and the like, in addition to the decubitus. The imaging direction includes a back surface, a side surface, and the like, in addition to the front surface. The operator OP operates the touch panel display59to select one imaging menu62that matches the imaging technique designated in the imaging order61from among the plurality of types of imaging menus62. As a result, the CPU57receives the imaging menu62. The CPU57reads out the irradiation condition63corresponding to the received imaging menu62from an irradiation condition table64stored in the storage55. The CPU57displays the read out irradiation condition63on the touch panel display59. In the irradiation condition table64, the irradiation conditions63corresponding to the various imaging menus62are registered. As described above, the irradiation condition63is the tube voltage and the tube current applied to the radiation tube21, and the irradiation time of the radiation R. Instead of the tube current and the irradiation time, a tube current irradiation time product may be set as the irradiation condition63.

The CPU57transmits the set irradiation condition63to the radiation source control device23via the communication I/F58. In addition, although not shown, in a case in which the radiation source control device23is instructed to start the irradiation with the radiation R through the irradiation switch16, the CPU57receives an irradiation start signal indicating that the irradiation with the radiation R is started from the radiation source control device23. In a case in which the irradiation start signal is received, the CPU57transmits a synchronization signal65indicating that the irradiation with the radiation R is started to the electronic cassette11. Further, the CPU57receives an irradiation end signal indicating that the irradiation with the radiation R ends from the radiation source control device23. In a case in which the irradiation end signal is received, the CPU57transmits the synchronization signal65indicating that the irradiation with the radiation R ends to the electronic cassette11.

In a case in which the synchronization signal65indicating that the irradiation with the radiation R is started is received from the console12, the electronic cassette11causes the detection panel35to start the accumulation operation. In addition, in a case in which the synchronization signal65indicating that the irradiation with the radiation R ends is received from the console12, the electronic cassette11causes the detection panel35to start the readout operation. It should be noted that the electronic cassette11may be provided with a function of detecting the start of the irradiation with the radiation R and the end of the irradiation with the radiation R, the detection panel35may be caused to start the accumulation operation in a case in which the start of the irradiation with the radiation R is detected by this function, and the detection panel35may be caused to start the readout operation in a case in which the end of the irradiation with the radiation R is detected.

The CPU57receives the radiation image66from the electronic cassette11via the communication I/F58. The CPU57performs various types of image processing on the radiation image66, and then displays the radiation image66on the touch panel display59and provides the radiation image66for viewing by the operator.

In addition, although not shown, the CPU57transmits the imaging instruction to the camera13via the communication I/F58. The CPU57receives the optical image40captured by the camera13in response to the imaging instruction.

As an example, as shown inFIG.6, an operation program70is stored in the storage55. The operation program70is an application program causing the computer to function as the imaging support apparatus. That is, the operation program70is an example of an “operation program of an imaging support apparatus” according to the technology of the present disclosure. Correspondence relationship information71, extraction reference information72, and the like are also stored in the storage55.

In a case in which the operation program70is activated, the CPU57cooperates with the memory56and the like to function as a first acquisition unit75, a second acquisition unit76, a first demarcation unit77, a second demarcation unit78, and a display controller79.

The first acquisition unit75sequentially acquires the optical images40output from the camera13at a predetermined frame rate. The first acquisition unit75outputs the optical image40to the first demarcation unit77, the second demarcation unit78, and the display controller79. The second acquisition unit76acquires the bed detection region information47from the electronic cassette11. The second acquisition unit76outputs the bed detection region information47to the first demarcation unit77.

The first demarcation unit77demarcates the detection region DR in the optical image40based on the bed detection region information47and the correspondence relationship information71. The first demarcation unit77outputs image detection region information85, which is information of the demarcated detection region DR, to the display controller79.

The second demarcation unit78demarcates an imaging region IR (seeFIG.10), which is a region to be imaged by the radiography, in the optical image40based on the extraction reference information72. The imaging region IR is a region preset in accordance with the imaging menu62, and is a region of a human body that should be included in the radiation image66in the imaging menu62. The second demarcation unit78outputs imaging region information86, which is information of the demarcated imaging region IR, to the display controller79.

The display controller79performs control of displaying various screens on the touch panel display59. The various screens include a display screen of the imaging order61, a selection screen of the imaging menu62, an information display screen95(seeFIGS.11to13), and the like. It should be noted that, although not shown, in the CPU57, in addition to the processing units75to79, a reception unit that receives the imaging order61from the RIS60, an image processing unit that performs various types of image processing on the radiation image66, a setting unit that sets the irradiation condition63in the radiation source control device23, and the like are constructed.

In the following, a case of chest portion decubitus front surface imaging will be described as an example.

As shown inFIG.7as an example, the correspondence relationship information71includes a function F for converting the bed position coordinate BI (x, y) into the position coordinate OI (X, Y) of the optical image40. The first demarcation unit77uses the function F to convert the bed position coordinates BI_DRP1(x, y) to BI_DRP4(x, y) of the four vertexes DRP1to DRP4of the detection region DR of the bed detection region information47the position coordinates OI_DRP1(X, Y), OI_DRP2(X, Y), OI_DRP3(X, Y), and OI_DRP4(X, Y) of the optical image40to obtain the image detection region information85. It should be noted that an origin of the position coordinates OI (X, Y) of the optical image40is, for example, a left end of the optical image40, an X-axis is a direction along the short side of the optical image40, and a Y-axis is a direction along the long side of the optical image40.

The first demarcation unit77corrects the function F of the correspondence relationship information71by transmitter position information88. The transmitter position information88is obtained by performing image recognition on the radio wave transmitter45shown in the optical image40. The transmitter position information88is specifically the position coordinate OI (X, Y) of the radio wave transmitter45in the optical image40and the size of the radio wave transmitter45. The position and the size of the radio wave transmitter45in the optical image40is changed in accordance with a position of the camera13with respect to the bed18. Therefore, the transmitter position information88can be referred to as information indicating a positional relationship between the camera13and the bed18. The radio wave transmitter45functions as a marker for recognizing the position of the camera13with respect to the bed18, in addition to transmitting the radio waves RW.

As shown inFIG.8as an example, the second demarcation unit78performs feature point extraction processing90on the optical image40. The feature point extraction processing90is processing of extracting a feature point91of the subject H shown in the optical image40by using a well-known image recognition technology or a machine learning model. From the top, the feature points91are right and left orbital points, right and left external auditory canal points, right and left shoulder joint points, right and left hip joint points, and right and left knee joint points. As is well known, an orbit is a depression in which an eyeball is accommodated, and the orbital point is a center point of the depression. An external auditory canal is a so-called ear canal, and the external auditory canal point is a center point of the ear canal. The shoulder joint point is a connection point between a shoulder blade and a humerus. The hip joint point is a connection point between a hip bone and a femoral bone. The knee joint point is a connection point between the femoral bone and a shinbone.

As shown inFIG.9as an example, the second demarcation unit78performs the feature point extraction processing90and then portion-of-interest extraction processing92on the optical image40. The portion-of-interest extraction processing92is processing of extracting a portion of interest POI from the feature point91with reference to the extraction reference information72. The portion of interest POI in the present example is a center point of the prominent vertebra (hereinafter, referred to as a prominent vertebra point). Therefore, the extraction reference information72is information for specifying the prominent vertebra. Specifically, the extraction reference information72is a content in which a point 1.2 times a length of the line L3, which connects a midpoint MP1of the line L1connecting the right and left shoulder joint points and a midpoint MP2of the line L2connecting the right and left hip joint points, is set as the prominent vertebra point. Therefore, a length of a line connecting the midpoint MP2and the prominent vertebra point is 1.2 times the length of the line L3.

It should be noted that the numerical value of “1.2 times” of the extraction reference information72is statistically obtained from the data of a large number of unspecified subjects H in the past. For example, the numerical values may be changed in accordance with the attribute of the subject H, such as gender, age, and body type, such as 1.2 times for men, 1.18 times for women, 1.12 times for children, and 1.22 times for height of 180 cm or more.

As shown inFIG.10as an example, the second demarcation unit78demarcates a rectangular region which has a center of the upper side at the prominent vertebra point, the rectangular region having a size corresponding to a source to image receptor distance (SID) and the field of view FOV of the camera13, as the imaging region IR. As is well known, the SID is a distance from a generation point of the radiation R to the surface of the detection panel35. The SID can be obtained from the size of the radio wave transmitter45shown in the optical image40. The second demarcation unit78outputs the position coordinates OI_IRP1(X, Y), OI_IRP2(X, Y), OI_IRP3(X, Y), and OI_IRP4(X, Y) of the four vertexes IRP1, IRP2, IRP3, and IRP4of the imaging region IR to the display controller79, as the imaging region information86. It should be noted that, even in the position coordinate OI (X, Y) of the diagonal point of the imaging region IR, such as the position coordinate OI_IRP1(X, Y) and the position coordinate OI_IRP4(X, Y), may be output as the imaging region information86.

The information display screen95also includes a display region98of the optical image40. An imaging instruction button99is provided on the upper portion of the display region98. The imaging instruction button99is a turning on/off button. In a state in which the imaging instruction button99is turned off, the imaging instruction for the optical image40is not transmitted to the camera13. Therefore, the optical image40is not displayed in the display region98. On the other hand, in a case in which the imaging instruction button99is turned on, the imaging instruction for the optical image40is transmitted to the camera13, so that the optical image40is displayed in the display region98. The display controller79displays the optical images40output from the camera13at a predetermined frame rate in the display region98while sequentially updating the optical images40. That is, the optical image40displayed in the display region98is a live view image (moving image).

The display controller79displays a frame100indicating the detection region DR on the optical image40of the display region98in a superimposed manner based on the image detection region information85. In addition, the display controller79displays a frame101indicating the imaging region IR on the optical image40of the display region98in a superimposed manner based on the imaging region information86. It should be noted that the frame100is an example of an “indicator indicating the detection region” according to the technology of the present disclosure. In addition, the frame101is an example of an “indicator indicating an imaging region” according to the technology of the present disclosure.

FIG.11shows the information display screen95before the electronic cassette11is inserted between the subject H and the bed18. In this case, the subject H is shown in the optical image40, whereas the electronic cassette11is not shown in the optical image40. Therefore, only the frame101indicating the imaging region IR is displayed on the optical image40of the display region98in a superimposed manner.

FIG.12shows the information display screen95during the insertion of the electronic cassette11between the subject H and the bed18. In this case, the optical image40also shows the electronic cassette11in addition to the subject H. Therefore, in addition to the frame101indicating the imaging region IR, the frame100indicating the detection region DR is also displayed on the optical image40of the display region98in a superimposed manner.

FIG.13shows the information display screen95in a case in which the insertion of the electronic cassette11between the subject H and the bed18ends. In this case as well, as in the case ofFIG.12, the frame100indicating the detection region DR and the frame101indicating the imaging region IR are displayed on the optical image40in the display region98in a superimposed manner.

Next, an action with the configuration described above will be described with reference to the flowchart shown inFIG.14as an example. Prior to the radiography, the operator performs imaging preparation work. The imaging preparation work includes selection of the imaging menu62, setting of the irradiation condition63of the radiation R, installation of the radio wave transmitter45on the bed18, position adjustment of the subject H on the bed18, position adjustment of the radiation source15with respect to the bed18(adjustment of the horizontal position and the SID), the size adjustment of the irradiation field, the position adjustment of the electronic cassette11, and the like.

In the console12, the operation program70is activated, so that the CPU57functions as the first acquisition unit75, the second acquisition unit76, the first demarcation unit77, the second demarcation unit78, and the display controller79.

The operator OP operates the console12to select the imaging menu62in accordance with the radiography to be performed, and then sets the irradiation condition63for the radiation R. The operator OP installs the radio wave transmitter45at each of the two corners of the bed18on the head portion side of the subject H. Thereafter, the operator OP performs the position adjustment of the subject H such that the head-caudal direction is parallel to the long side direction of the bed18.

The operator OP expands and contracts the first arm19and the second arm20to perform the position adjustment of the radiation source15with respect to the bed18. In addition, the operator OP operates the irradiation field limiter22to perform the size adjustment of the irradiation field.

Before inserting the electronic cassette11between the subject H and the bed18, the operator OP turns on the imaging instruction button99on the information display screen95to issue the imaging instruction for the optical image40(YES in step ST100). The imaging instruction is transmitted to the camera13from the console12(step ST110). As a result, as shown inFIG.3, the optical image40is captured by the camera13.

The optical image40from the camera13is acquired by the first acquisition unit75(step ST120). The optical image40is output to the first demarcation unit77, the second demarcation unit78, and the display controller79from the first acquisition unit75.

In addition, as shown inFIG.4, in a case in which an attempt is made to insert the electronic cassette11between the subject H and the bed18, the radio wave RW from the radio wave transmitter45is received by the radio wave receiver36of the electronic cassette11, and the received radio wave intensity thereof is output as the detection result46. In the electronic cassette11, based on the detection result46, the bed detection region information47, which includes the bed position coordinates BI_DRP1(x, y) to BI_DRP4(x, y) of the four vertexes DRP1to DRP4of the detection region DR of the radiation R by the detection panel35, is derived.

The bed detection region information47from the electronic cassette11is acquired by the second acquisition unit76(step ST130). The bed detection region information47is output to the first demarcation unit77from the second acquisition unit76. It should be noted that, in a case in which the electronic cassette11is at a position at which the radio wave RW from the radio wave transmitter45cannot be received, step ST130is omitted.

As shown inFIG.7, in the first demarcation unit77, the image detection region information85is derived from the bed detection region information47by using the correspondence relationship information71. As a result, the detection region DR is demarcated in the optical image40(step ST140). The image detection region information85is output to the display controller79from the first demarcation unit77.

As shown inFIGS.8and9, in the second demarcation unit78, the feature point extraction processing90and the portion-of-interest extraction processing92are performed on the optical image40to extract the portion of interest POI (here, the prominent vertebra point). Then, as shown inFIG.10, the imaging region IR is demarcated in the optical image40based on the portion of interest POI by the second demarcation unit78(step ST150). The imaging region information86, which is the information of the demarcated imaging region IR, is output to the display controller79from the second demarcation unit78.

After the imaging preparation work ends, the operator OP instructs the subject H to inhale and stop. Thereafter, the operator OP operates the irradiation switch16to instruct the radiation source15to start irradiation with the radiation R. As a result, the radiation R is emitted from the radiation source15toward the subject H.

The radiation R transmitted through the subject H reaches the electronic cassette11. Then, the radiation R is detected as the radiation image66by the detection panel35of the electronic cassette11. The radiation image66is output to the console12from the electronic cassette11. Then, on the console12, various types of image processing are performed on the radiation image66from the electronic cassette11. Thereafter, the radiation image66is displayed in the display region98instead of the optical image40.

As described above, the CPU57of the console12comprises the first acquisition unit75, the first demarcation unit77, the second demarcation unit78, and the display controller79. The first acquisition unit75acquires the optical image40in which both the electronic cassette11in which the detection panel35for detecting the radiation R is built in the portable housing30and the subject H facing the radiography using the electronic cassette11are shown, from the camera13. The first demarcation unit77demarcates the detection region DR of the radiation R by the detection panel35, the detection region DR being determined in accordance with the position of the electronic cassette11, in the optical image40. The second demarcation unit78demarcates the imaging region IR which is the region to be imaged in the radiography, the imaging region IR being determined in accordance with the position of the subject H, in the optical image40. The display controller79performs control of displaying the frame100indicating the detection region DR and the frame101indicating the imaging region IR on the touch panel display59in a manner of being superimposed on the optical image40.

Therefore, the operator OP can adjust the position of the electronic cassette11such that the imaging region IR is included in the detection region DR. Therefore, it is possible to contribute to more accurate positioning of the electronic cassette11with respect to the subject H. It is particularly suitable in a case in which the electronic cassette11is covered and hidden by the subject H and it is difficult to visually recognize the electronic cassette11as in the example of the chest portion decubitus front surface imaging. It is possible to reduce a concern that a situation occurs in which the imaging is performed in a state in which the detection region DR does not cover the imaging region IR. In addition, since the positioning of the electronic cassette11can be easily performed, a time required for the radiography can be shortened, and the stress on the subject H due to the restraint for a long time can be reduced.

The first demarcation unit77demarcates the detection region DR based on the detection result46of the radio wave receiver36which is the position detection sensor that detects the position of the electronic cassette11, more specifically, the bed detection region information47derived from the detection result46. Therefore, the detection region DR can be easily demarcated.

The second demarcation unit78extracts the portion of interest POI of the subject H included in the optical image40, and demarcates the imaging region IR based on the portion of interest POI. Therefore, the imaging region IR can be more accurately demarcated than in a case in which the imaging region IR is directly demarcated from the optical image40.

Modification Example

The case of the chest portion decubitus front surface imaging has been described as an example so far, but in this modification example, a case of knee decubitus side surface imaging will be described. In this case, as shown inFIG.15, as an example, the subject H lies down on his/her side on the bed18in a state in which the knee imaged by the radiography, in this case, the left knee is left down and bent. The operator OP uses an auxiliary tool, such as a cushion and/or a table, as necessary in order to maintain the posture of the subject H.

As shown inFIG.16as an example, in the optical image40in this case, about ½ of the bed18and from the waist of the subject H lying down on his/her side on the bed18to the toes of the feet, that is, a part of the upper body and the entire lower body are shown. The second demarcation unit78performs the feature point extraction processing90on the optical image40, and extracts the right and left hip joint points, the right and left knee joint points, and the right and left ankle joint points as the feature points91. The ankle joint point is the connection point between the shinbone and a talus. The second demarcation unit78extracts a left knee joint point of the feature points91as the portion of interest POI. Therefore, the left knee joint point is also the feature point91and is also an example of a “portion of interest” according to the technology of the present disclosure. In addition, the feature point extraction processing90is also the portion-of-interest extraction processing92.

As shown inFIG.17as an example, the second demarcation unit78demarcates a rectangular region which has a center at the left knee joint point, the rectangular region having a size corresponding to the SID and the field of view FOV of the camera13, as the imaging region IR. Although not shown, the second demarcation unit78outputs the position coordinates OI_IRP1(X, Y) to OI_IRP4(X, Y) of the four vertexes IRP1to IRP4of the imaging region IR as the imaging region information86, as display controller79.

As described above, the imaging part is not limited to the chest portion but may be the knee. In addition to the chest portion and knee, the imaging part may be a head portion, a neck portion, an abdomen portion, a waist portion, a shoulder, an elbow, a hand, an ankle, or the like, although illustration and detailed description are omitted. Similarly, the imaging posture of the subject H does not have to be in the decubitus as shown in the example, and may be the upright or the sitting. The imaging direction is not limited to the front surface and the side surface, and may be the back surface.

Second Embodiment

As shown inFIG.18as an example, a bed110according to the second embodiment is provided with an optical display112on a side portion111along the long side direction thereof. The optical display112has a configuration in which a plurality of light sources113are arranged without gaps along the long side direction of the bed18. The light source113is, for example, a light-emitting diode (LED).

As shown inFIG.19as an example, the CPU57of the console12according to the second embodiment functions as an optical display controller120, in addition to the processing units75to79according to the first embodiment (not shown except for the second demarcation unit78). The optical display controller120controls an operation of the optical display112. The imaging region information86is input to the optical display controller120from the second demarcation unit78. The optical display controller120converts the position coordinates OI_IRP1(X, Y) to OI_IRP4(X, Y) of the vertexes IRP1to IRP4of the imaging region IR of the imaging region information86into the bed position coordinates BI_IRP1(x, y) to BI_IRP4(x, y) by using an inverse function F-′ of the function F shown inFIG.7. The optical display controller120operates the optical display112to turn on, for example, all the light sources113at positions including the y-coordinates of the bed position coordinates BI_IRP1(x, y) and BI_IRP3(x, y) to display an insertion position of the electronic cassette11corresponding to the imaging region IR.

As described above, in the second embodiment, in a state in which the subject H lies down on the bed18, in a case in which the electronic cassette11is inserted between the subject H and the bed18and the radiography is performed, the optical display controller120operates the optical display112that displays light for the position adjustment of the electronic cassette11on the side portion111along the long side direction of the bed18to display the insertion position of the electronic cassette11corresponding to the imaging region IR. Therefore, the operator OP can grasp at a glance from where the electronic cassette11should be inserted, and the position adjustment of the electronic cassette11is further improved.

The optical display is not limited to the optical display112in which the plurality of light sources113described as an example are connected. A projector that projects light for position adjustment of the electronic cassette11onto the side portion111may be used.

In a case in which the radiography is to be performed in a state in which the imaging region IR is not included in the detection region DR, a message indicating a state in which the imaging region IR is not included in the detection region DR is displayed on the information display screen95and the notification may be performed with respect to the operator OP. The operator OP may be notified by voice of a state in which the imaging region IR is not included in the detection region DR. In addition, an indicator, such as a warning lamp, may be used for the notification. Alternatively, in a case in which radiography is to be performed in a state in which the imaging region IR is not included in the detection region DR, the irradiation with the radiation R by the radiation source15may be prohibited.

The indicator indicating the detection region DR is not limited to the frame100described as an example. An L-shaped line representing the four vertexes DRP1to DRP4of the detection region DR may be used. Also, the indicator indicating the imaging region IR is not limited to the frame101described as an example, and an L-shaped line representing the four vertexes IRP1to IRP4of the imaging region IR may be used.

The position detection sensor is not limited to the radio wave receiver36described as an example. The position of the electronic cassette11may be detected by pressure-sensitive sensors arranged in a two-dimensional matrix on the surface of the top plate of the bed18. In addition, a marker may be attached to the surface of the electronic cassette11and the image recognition may be performed on the marker shown in the optical image40to detect the position of the electronic cassette11. In this case, the camera13serves as the position detection sensor.

The light sources may be arranged in a row along the side portion of the bed18, a light receiving sensor may be provided on the side portion opposite to the light source, and the position of the electronic cassette11may be detected by a light shielding state of the electronic cassette11. In addition, the position of the electronic cassette11may be detected by an ultrasound sensor. In short, the position detection sensor may be any device as long as the position of the electronic cassette11can be detected.

Examples of the portion of interest POI include the following in addition to the prominent vertebra point and the like described as an example. That is, examples thereof include laryngeal prominence (thyroid cartilage) in a case in which the imaging part is the head portion, suprasternal space, shoulder blade lower end, xiphoid process, and rib lower edge in which the imaging part is the chest portion, iliac crest upper edge (line connecting right and left iliac crests (Jacoby's line)), anterior superior iliac spine, pubic symphysis/greater trochanter, and coccyx in a case in which the imaging part is the waist portion. These examples are so-called body surface indicators.

An installation position of the camera13is not limited to the radiation source15. A ceiling, a wall, or the like of the hospital room may be used. In addition, although the mobile radiation generation device10has been described as an example, the present disclosure is not limited to this. A radiation generation device installed in the radiography room may be used.

The console12may be built in the mobile radiation generation device10. In this case, various screens, such as the information display screen95, may be transmitted to a portable terminal, such as a tablet terminal owned by the operator, from the console12, for example, in a form of screen data for web distribution created by markup language, such as extensible markup language (XML). In this case, the portable terminal reproduces various screens to be displayed on the web browser based on the screen data and displays the screens on the display. It should be noted that, instead of the XML, another data description language, such as Javascript (registered trademark) object notation (JSON), may be used.

It is possible to make various modifications with respect to the hardware configuration of the computer constituting the imaging support apparatus according to the technology of the present disclosure. For example, the imaging support apparatus can be composed of a plurality of computers separated as hardware in order to improve the processing capacity and the reliability. For example, the functions of the first acquisition unit75and the second demarcation unit78and the functions of the second acquisition unit76, the first demarcation unit77, and the display controller79are distributed to two computers and carried out. In this case, the two computers constitute the imaging support apparatus.

As described above, the hardware configuration of the computer of the imaging support apparatus can be appropriately changed in accordance with required performance, such as processing capacity, safety, and reliability. Further, it is needless to say that, in addition to the hardware, an application program, such as the operation program70, can be duplicated or distributed and stored in a plurality of storages for the purpose of securing the safety and the reliability.

In each of the embodiments described above, as the hardware structure of the processing units that execute various processing, such as the first acquisition unit75, the second acquisition unit76, the first demarcation unit77, the second demarcation unit78, the display controller79, and the optical display controller120, the following various processors can be used. As described above, the various processors include, in addition to the CPU57, which is a general-purpose processor that executes software (operation program70) to function as the various processing units, a programmable logic device (PLD), which is a processor of which a circuit configuration can be changed after the manufacturing, such as a field programmable gate array (FPGA), a dedicated electric circuit, which is a processor having a circuit configuration designed exclusively for executing specific processing, such as an application specific integrated circuit (ASIC), and the like.

One processing unit may be composed of one of various processors described above or may be composed of a combination of two or more processors (for example, a combination of a plurality of ASICs and/or a combination of an ASIC and a FPGA) of the same type or different types. In addition, a plurality of the processing units may be composed of one processor.

As an example in which the plurality of processing units are composed of one processor, firstly, as represented by a computer, such as a client and a server, there is a form in which one processor is composed of a combination of one or more CPUs and software, and the processor functions as the plurality of processing units. Second, as represented by a system on chip (SoC) or the like, there is a form in which a processor, which realizes the functions of the entire system including the plurality of processing units with a single integrated circuit (IC) chip, is used. As described above, various processing units are composed of one or more of the various processors as the hardware structure.

Further, as the hardware structure of these various processors, more specifically, it is possible to use an electric circuit (circuitry) in which circuit elements, such as semiconductor elements, are combined.

The technology of the present disclosure can also be appropriately combined with various embodiments and/or various modification examples described above. In addition, it is needless to say that the present disclosure is not limited to each of the embodiments described above, various configurations can be adopted as long as the configuration does not deviate from the gist. Further, the technology of the present disclosure includes, in addition to the program, a storage medium that stores the program in a non-transitory manner.

The described contents and shown contents above are the detailed description of the parts according to the technology of the present disclosure, and are merely an example of the technology of the present disclosure. For example, the above description of the configuration, the function, the action, and the effect are the description of examples of the configuration, the function, the action, and the effect of the parts according to the technology of the present disclosure. Accordingly, it is needless to say that unnecessary parts may be deleted, new elements may be added, or replacements may be made with respect to the described contents and shown contents above within a range that does not deviate from the gist of the technology of the present disclosure. In addition, in order to avoid complications and facilitate grasping the parts according to the technology of the present disclosure, in the described contents and shown contents above, the description of technical general knowledge and the like that do not particularly require description for enabling the implementation of the technology of the present disclosure are omitted.

In the present specification, “A and/or B” is synonymous with “at least one of A or B”. That is, “A and/or B” means that it may be only A, only B, or a combination of A and B. In addition, in the present specification, also in a case in which three or more matters are associated and expressed by “and/or”, the same concept as “A and/or B” is applied.

All documents, patent applications, and technical standards described in the present specification are incorporated herein by reference to the same extent as in a case in which each document, each patent application, and each technical standard are specifically and individually described by being incorporated by reference.