JP2015156896A - Radiographic apparatus, control method thereof, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiographic apparatus that can be easily and quickly installed when performing radiographic imaging by alleviating complex work to cause a radiation generation part and a radiation detection part to face each other.SOLUTION: A radiographic apparatus includes a radiation source 106 for applying radiation, a radiation sensor 108 for receiving the radiation applied from the radiation source 106 and imaging it, cameras 130L and 130R for detecting the radiation sensor 108, a calculation part for calculating the position of the radiation sensor 108 detected by the cameras 130L and 130R, and a movement control part for moving the radiation source 106 to a position facing the radiation sensor 108 based on the position of the radiation sensor 108 calculated by the calculation part.

Description

  The present invention relates to a radiation imaging apparatus, a control method thereof, and a program.

  Among the radiation imaging apparatuses, the mobile radiation imaging apparatus can perform radiation imaging without moving the patient by moving the apparatus main body according to the imaging region of the patient.

  Patent Document 1 discloses a radiation detection cassette having a radiation detection cassette having a radiation detector that detects radiation that has passed through a subject and converts the radiation into radiation image information, and a radiation source that can be moved by a carriage. A radiographic imaging system including a unit is disclosed. The operator can perform radiation imaging by disposing the radiation detection cassette below the imaging region of the subject and disposing the radiation source at a position facing the radiation detection cassette.

JP 2009-28449 A

  However, the radiographic imaging system described above has a problem that it is not easy for an operator to accurately arrange the radiation source at a position facing the radiation detection cassette. Specifically, the operator has to adjust the radiation source while visually confirming from a different direction by changing the angle, for example, whether the radiation source is facing the radiation detection cassette.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to reduce a complicated work of making a radiation generation unit and a radiation detection unit face each other.

  The radiation imaging apparatus of the present invention includes: a radiation generation unit that exposes radiation; a radiation detection unit that receives and images radiation emitted from the radiation generation unit; and a calculation that calculates a position of the radiation detection unit And a movement control unit that moves the radiation generation unit to a position facing the radiation detection unit based on the position of the radiation detection unit calculated by the calculation unit.

  ADVANTAGE OF THE INVENTION According to this invention, the complicated operation | work which makes a radiation source and a radiation detection part oppose can be reduced.

It is a side view which shows the structure of the mobile radiography apparatus of this embodiment. It is a figure which shows the structure of a radiation sensor. It is a block diagram which shows the structure of the mobile radiography apparatus of 1st Embodiment. It is a flowchart which shows the process of the mobile radiography apparatus of 1st Embodiment. It is a block diagram which shows the structure of the mobile radiography apparatus of 2nd Embodiment. It is a flowchart which shows the process of the mobile radiography apparatus of 2nd Embodiment. It is a figure for demonstrating the method of calculating a three-dimensional coordinate from two images.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a side view showing a configuration of a mobile radiation imaging apparatus 100 as the radiation imaging apparatus of the present embodiment.
The mobile radiography apparatus 100 has a traveling carriage 102 that can travel on wheels 101 composed of a pair of left and right rear wheels and front wheels. The traveling carriage 102 is traveled by using a travel drive unit 304 (see FIG. 3) such as an electric motor that is driven by a battery as a power source, and can also travel manually. The traveling carriage 102 is equipped with a control unit unit 120 that controls the entire mobile radiography apparatus 100, an operation unit 121 for an operator to instruct the control unit unit 120, a battery (not shown), and the like.
Further, a prop 103 is erected on the traveling carriage 102 so as to be turnable about an axis. The column 103 is turned using a turning drive unit 305 (see FIG. 3) such as an electric motor that is driven by a battery as a power source, and can also be turned manually.

  The support column 103 supports the arm support unit 104 so as to be movable up and down. The arm support unit 104 is lifted and lowered using a lift drive unit 306 (see FIG. 3) such as an electric motor that is driven by a battery as a power source, and can also be lifted manually. The arm support unit 104 supports the arm portion 105 in a horizontally cantilevered manner so as to be extendable and contractible. The arm unit 105 is expanded and contracted by using an expansion / contraction drive unit 307 (see FIG. 3) such as an electric motor that is driven by a battery as a power source, and can also be expanded and contracted manually.

  The arm unit 105 supports a radiation source 106 as a radiation generation unit at a tip thereof so as to be swingable. The radiation source 106 is oscillated by a front-rear rotation axis that is supported along the axis of the arm unit 105 and a left-right rotation axis that is orthogonal to the axis of the arm unit 105, thereby arbitrarily setting the radiation source 106. It is possible to direct radiation in the direction of. The radiation source 106 is swung by rotating a rotating shaft 111 (see FIG. 3) by a swing driving unit 308 (see FIG. 3) such as an electric motor that is driven by a battery as a power source. It can swing. Further, the radiation source 106 emits radiation according to an instruction via the operation unit 121 by the operator. Here, the radiation source 106 can irradiate the radiation continuously one or more times per second.

  A radiation stop 107 is attached to the lower end of the radiation source 106. The radiation diaphragm 107 adjusts the exposure area of the radiation emitted from the radiation source 106 in order to reduce unnecessary exposure to the patient. The radiation diaphragm 107 is swung integrally when the radiation source 106 is swung with respect to the arm unit 105.

  The mobile radiation imaging apparatus 100 has a radiation sensor 108 as a radiation detection unit. The radiation sensor 108 is disposed between the patient S and the bed T at the time of radiography, and receives and images radiation emitted from the radiation source 106 and transmitted through the patient S. Here, the radiation sensor 108 can receive and image radiation continuously at one or more sheets per second. The radiographic image captured by the radiation sensor 108 is received by the control unit 120 by wireless or wired and displayed on the monitor of the operation unit 121.

FIG. 2 is a diagram illustrating the configuration of the radiation sensor 108. The radiation sensor 108 of the present embodiment is provided with a cross mark 109 that is a detection mark as a characteristic part at the center of the surface. The cross mark 109 is detected by the control unit 120 and used when calculating the three-dimensional coordinates of the radiation sensor 108.
Since the width of the general bed T is 510 to 650 mm, the size of the radiation sensor 108 is narrower than the width of the bed T, for example, 500 mm square. The smaller size is preferably 430 mm square with the same size as the long side of the half-cut film cassette, such as when placed under the patient S during surgery. In the case of spinal surgery, there are many operations related to the fourth lumbar vertebra, the fifth lumbar vertebra, and the first sacral vertebra. In this case, if the size is 430 mm square, it is possible to photograph a wide area including the lumbar vertebra and the first sacral vertebra at a time. Therefore, if the imaging region of the patient S is roughly arranged on the radiation sensor 108 at the start of surgery, the detection range of the radiation sensor 108 is wide, and therefore only the radiation diaphragm 107 needs to be finely adjusted.

  Further, the radiation sensor 108 incorporates a triaxial tilt sensor 110 as a tilt detection unit. The tilt sensor 110 transmits tilt information corresponding to the tilt angle to the control unit 120 when the bed T is tilted, for example.

  By using such a radiation sensor 108 and the radiation source 106, for example, in an intraoperative cholangiography examination, the acquired image is reproduced on the monitor of the operation unit 121, so that the contrast medium spreads from the bile duct to the liver, etc. for 1 second. One or more continuous images can be confirmed. Since the image can be displayed earlier than the imaging interval, the time for the surgeon to observe the image can be shortened, and the operation time can be shortened accordingly.

Next, the mobile radiation imaging apparatus 100 of the present embodiment includes a detection unit 130 that detects the radiation sensor 108. Here, the detection unit 130 uses, for example, two cameras 130 </ b> L and 130 </ b> R as imaging means using a CCD or CMOS as an image sensor.
In the present embodiment, two cameras 130L and 130R are installed on the arm support unit 104 so as to be separated from each other on the left and right. The two cameras 130L and 130R have a horizontal parallax. The two cameras 130 </ b> L and 130 </ b> R are not limited to being installed on the arm support unit 104, and may be installed on the support column 103, the arm unit 105, or the radiation source 106. Note that the cameras 130L and 130R include at least the floor surface directly below the radiation source 106 when the arm unit 105 is extended and the floor surface directly below the radiation source 106 when the arm unit 105 is contracted most. The angle of view is preferably set so that

The mobile radiation imaging apparatus 100 according to the present embodiment detects, for example, a cross mark 109 that is a characteristic part of the radiation sensor 108 from a plurality (two) of images captured by the cameras 130L and 130R, and causes the radiation source 106 to emit radiation. The sensor is moved to a position facing the sensor.
FIG. 3 is a diagram illustrating a functional configuration of the control unit 120. The control unit unit 120 includes a calculation unit 301, a movement control unit 302, and a control unit 303. These functional configurations can be realized by the CPU installed in the control unit 120 executing a program stored in the ROM.

The calculation unit 301 detects the cross mark 109 as a characteristic part of the radiation sensor 108 from the images taken by the cameras 130L and 130R, and calculates the position of the radiation sensor 108. Here, the calculation unit 301 calculates the three-dimensional coordinates (X, Y, Z) of the radiation sensor 108 with the camera center of the camera 130L as the origin.
As shown in FIG. 7, the coordinates of the cross mark 109 on the camera 130L (x _L , y _L ) and the image coordinates (x _R , y _R ) of the cross mark 109 on the camera 130R are coordinated by the principle of triangulation. Is calculated.
The three-dimensional coordinates (X, Y, Z) of the radiation sensor 108 can be calculated by the following formula.

Here, f is the focal length of the camera, h is the distance (baseline) between the cameras, and x _L -x _R is the parallax between the left and right cameras.
Similarly, the three-dimensional coordinates (x, y, z) of the radiation source 106 can be calculated by photographing the radiation source 106 with the cameras 130L and 130R. In other words, the calculation unit 301 determines the three-dimensional coordinates (x, y, z) can be calculated.

  Based on the three-dimensional coordinates (x, y, z) of the radiation sensor 108 calculated by the calculation unit 301, the movement control unit 302 has the irradiation field center of the radiation source 106 positioned vertically above the center of the radiation sensor 108. The radiation source 106 is moved so that That is, the movement control unit 302 uses the same X and Y coordinates in the three-dimensional coordinates (X, Y, Z) of the radiation sensor 108 and the three-dimensional coordinates (x, y, z) of the radiation source 106. The radiation source 106 is moved.

  Specifically, the movement control unit 302 swings the support column 103 via the turning drive unit 305 or expands / contracts the arm unit 105 via the expansion / contraction drive unit 307, so that the center of the radiation sensor 108 is vertically adjusted. The radiation source 106 is moved upward in the direction. Note that the calculation unit 301 determines whether the distance by which the radiation source 106 is moved to the upper part in the vertical direction at the center of the radiation sensor 108 exceeds the turning range by the support column 103 or the expansion / contraction range by the arm unit 105. When it is determined that the turning range or the expansion / contraction range is exceeded, the movement control unit 302 drives the wheel 101 via the traveling drive unit 304 and moves the traveling carriage 102 itself so as to approach the radiation sensor 108.

  Furthermore, the movement control unit 302 uses the elevation drive unit 306 so that the distance from the surface of the radiation sensor 108 to the focal point of the radiation source 106 becomes a predetermined height based on the coordinate information calculated by the calculation unit 301. The arm support unit 104 is moved up and down. The movement control unit 302 raises and lowers the arm support unit 104 so that the distance from the surface of the radiation sensor 108 to the focal point of the radiation source 106 is, for example, 100 cm.

  The operator may manually operate the radiation source 106 so that the radiation source 106 faces the radiation sensor 108. For example, a rotary encoder, a linear encoder, or the like is provided as a position sensor on the support column 103, the arm unit 105, and the like, and the movement control unit 302 sequentially detects the movement amount of the radiation source 106. In this case, the radiation source 106 is manually operated by the operator, and the movement control unit 302 electromagnetically locks the column unit 103, the arm unit 105, and the like so that the radiation source 106 stops at a position facing the radiation sensor 108. Therefore, the radiation source 106 is guided so as to be at the upper part in the vertical direction of the central portion of the radiation sensor 108.

  Further, the movement control unit 302 acquires the tilt information detected by the tilt sensor 110 incorporated in the radiation sensor 108 via the control unit 303, and the rotation shaft 111 via the swing drive unit 308 based on the tilt information. And the radiation source 106 is swung. Specifically, the movement control unit 302 moves the radiation source 106 so that the irradiation direction of the radiation source 106 is orthogonal to the surface of the radiation sensor 108. At this time, the movement control unit 302 turns the support column 103 via the turning drive unit 305 or expands / contracts the arm unit 105 via the extension drive unit 307 as necessary, so that the irradiation direction of the radiation source 106 is changed. The radiation source 106 is moved so as to be orthogonal to the surface of the radiation sensor 108.

  The operator may manually swing the radiation source 106 so that the irradiation direction of the radiation source 106 is orthogonal to the surface of the radiation sensor 108. In this case, the radiation controller 106 is manually swung by the operator, and the movement controller 302 electromagnetically rotates the rotation shaft 111 so that the irradiation direction of the radiation source 106 stops at a position orthogonal to the surface of the radiation sensor 108. Lock it. Therefore, the radiation source 106 is guided so that the irradiation direction is at a position orthogonal to the surface of the radiation sensor 108.

  The control unit 303 controls the radiation source 106 and the radiation diaphragm 107 and controls the driving of the radiation sensor 108 according to an instruction from the operator. Specifically, the control unit 303 adjusts the radiation aperture 107 and emits radiation according to an instruction from the operator via the operation unit 121. Further, the control unit 303 displays the radiation image imaged by the radiation sensor 108 on the monitor of the operation unit 121.

Next, a method for adjusting the position of the radiation source 106 by the mobile radiation imaging apparatus 100 configured as described above will be described with reference to the flowchart of FIG. The flowchart of FIG. 4 is started when the operator instructs the start of position adjustment via the operation unit 121 before placing the patient S on the bed T.
In step S41, the calculation unit 301 detects the cross mark 109 of the radiation sensor 108 from the images taken by the cameras 130L and 130R, and calculates the three-dimensional coordinates (X, Y, Z) of the radiation sensor 108 using the above formula. calculate. Similarly, the calculation unit 301 calculates the three-dimensional coordinates (x, y, z) of the radiation source 106.

  In step S <b> 42, the calculation unit 301 calculates a distance for moving the radiation source 106 to the upper part in the vertical direction at the center of the radiation sensor 108 based on the calculated coordinate information. The calculation unit 301 determines whether or not the calculated distance exceeds the turning range by the support column 103 or the expansion / contraction range by the arm unit 105. If it is determined that the distance to be moved exceeds the turning range or the expansion / contraction range, the process proceeds to step S43. If it is determined that the distance to be moved does not exceed the range, the process proceeds to step S44.

In step S <b> 43, the movement control unit 302 drives the wheel 101 via the travel drive unit 304 to move the travel cart 102 itself so as to approach the radiation sensor 108.
In step S <b> 44, the movement control unit 302 turns the support column 103 via the turning drive unit 305 and expands / contracts the arm unit 105 via the elevating drive unit 306, so that the radiation source 106 moves the vertical direction of the radiation sensor 108. The radiation source 106 is moved so as to be in the upper direction. Further, the movement control unit 302 uses the elevation drive unit 306 so that the distance from the surface of the radiation sensor 108 to the focal point of the radiation source 106 becomes a predetermined height based on the coordinate information calculated by the calculation unit 301. The arm support unit 104 is moved up and down. The radiation source 106 can be positioned opposite to the radiation sensor 108 by the process of step S44.

Thereafter, the operator places the patient S on the bed T, places the radiation sensor 108 between the patient S and the bed T, and tilts the bed T as necessary.
In step S45, the movement control unit 302 acquires the tilt information detected by the tilt sensor 110 of the radiation sensor 108 via the control unit 303, and rotates the rotating shaft 111 via the swing drive unit 308 based on the tilt information. Thus, the radiation source 106 is swung. The radiation source 106 can be positioned so that the irradiation direction of the radiation source 106 is orthogonal to the surface of the radiation sensor 108 by the process of step S45.

Thereafter, the operator can confirm the radiation image transmitted through the patient S on the monitor of the operation unit 121 by instructing radiation exposure via the operation unit 121.
As described above, according to the present embodiment, the radiation generation unit (radiation source 106) that emits radiation, and the radiation detection unit (radiation sensor 108) that receives and images radiation emitted from the radiation generation unit, Calculating means for calculating the position of the radiation detecting section (calculating section 301), and movement control means for moving the radiation generating section to a position facing the radiation detecting section based on the position of the radiation detecting section calculated by the calculating means. (Movement control unit 302). Therefore, when the radiation source 106 is moved to a position facing the radiation sensor 108, the operator does not need to perform complicated work, and radiation imaging can be installed easily and quickly.

(Second Embodiment)
Next, a mobile radiation imaging apparatus 500 as a radiation imaging apparatus according to the second embodiment will be described.
FIG. 5 is a diagram illustrating a functional configuration of the mobile radiation imaging apparatus 500. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment, and the description is abbreviate | omitted.
The mobile radiation imaging apparatus 500 of this embodiment includes an obstacle detection unit 530 that detects an obstacle. The obstacle detection unit 530 uses, for example, two cameras 530L and 530R as imaging means using CCD or CMOS as an image sensor. In the present embodiment, the two cameras 530L and 530R are installed, for example, on the support column 103 and the radiation source 106 so as to be separated from each other on the left and right.

  In addition, the control unit 520 of the mobile radiation imaging apparatus 500 according to the present embodiment determines whether or not an obstacle exists in a range in which the radiation source 106 is moved from a plurality of images captured by the cameras 530L and 530R. An obstacle determination unit 501 is included. When the obstacle determination unit 501 determines that an obstacle exists in the range in which the radiation source 106 is moved, the movement control unit 302 restricts the movement of the radiation source 106.

  Next, a method for adjusting the position of the radiation source 106 by the mobile radiation imaging apparatus 500 configured as described above will be described with reference to the flowchart of FIG. The flowchart of FIG. 6 is started when the operator instructs the start of position adjustment via the operation unit 121 before placing the patient S on the bed T. Note that the same processes as those in the flowchart of FIG. 4 are denoted by the same step numbers and description thereof is omitted.

If it is determined in step S42 that the distance to move the radiation source 106 exceeds the turning range or the expansion / contraction range, the process proceeds to step S61.
In step S61, the obstacle determination unit 501 determines whether there is an obstacle in a range in which the traveling carriage 102 is moved based on images captured by the cameras 530L and 530R. In this case, the obstacle may be a surgeon, a nurse with a tool or a surgical microscope or a surgical light. When it is determined that there is an obstacle, the movement control unit 302 restricts driving of the wheels 101 via the travel drive unit 304. Specifically, the movement control unit 302 stops driving the wheels 101 via the travel drive unit 304 and ends the process. The movement control unit 302 may stop the wheels 101 immediately before the traveling carriage 102 collides with an obstacle. If it is determined that no obstacle exists, the process proceeds to step S43.
After the traveling carriage 102 is moved in step S43, the process proceeds to step S62.

  In step S62, the obstacle determination unit 501 determines whether there is an obstacle in a range in which the radiation source 106 is moved based on images captured by the cameras 530L and 530R. Specifically, the obstacle determination unit 501 compares the distance by which the radiation sensor 108 calculated by the calculation unit 301 is moved with the coordinate information from the images taken by the cameras 530L and 530R to the obstacle detected. . Next, the obstacle determination unit 501 determines whether there is an obstacle in the range in which the radiation source 106 is moved according to the comparison result. When it is determined that there is an obstacle, the movement control unit 302 performs at least one of driving for expanding and contracting the arm unit 105 via the expansion / contraction driving unit 307 and driving for rotating the column unit 103 via the rotation driving unit 305. Restrict. Specifically, the movement control unit 302 stops the driving for expanding and contracting the arm unit 105 via the expansion / contraction driving unit 307 and the driving for rotating the column unit 103 via the turning driving unit 305 and ends the processing. Note that the movement control unit 302 may stop the movement of the radiation source 106 immediately before the radiation source 106 collides with an obstacle. If it is determined that no obstacle exists, the process proceeds to step S44.

  As described above, according to the present embodiment, when the radiation source 106 is automatically moved to a position facing the radiation sensor 108, the radiation source 106 can be prevented from colliding with an obstacle. In the present embodiment, the cameras 530L and 530R serving as the obstacle detection unit 530 are described as being separate from the cameras 130L and 130R. However, the present invention is not limited to this case. For example, the camera as the obstacle detection unit 530 may be shared with the cameras 130L and 130R as the detection unit 130.

As described above, the present invention has been described together with various embodiments, but the present invention is not limited to these embodiments, and can be modified within the scope of the present invention. May be.
The present invention can also be realized by executing the following processing. That is, a program that realizes the functions of the above-described embodiment is supplied to the mobile radiography apparatuses 100 and 500 via a network or various storage media, and a computer (such as a CPU) of the control unit 120 of the apparatus executes the program. It is a process to read and execute.

  DESCRIPTION OF SYMBOLS 100, 500: Mobile radiography apparatus 101: Wheel 102: Traveling carriage 103: Strut part 104: Arm support unit 105: Arm part 106: Radiation source (radiation generation part) 107: Radiation aperture 108: Radiation sensor (radiation detection part) 110: Inclination sensor 120: Control unit unit 121: Operation unit 130: Detection unit 130R, 130L: Camera 301: Calculation unit 302: Movement control unit 303: Control unit 304: Travel drive unit 305: Turn drive unit 306: Lift drive Unit 307: telescopic drive unit 308: swing drive unit 501: obstacle determination unit

Claims (8)

A radiation generator for exposing the radiation;
A radiation detection unit that receives and images radiation emitted from the radiation generation unit;
Calculating means for calculating the position of the radiation detection unit;
A radiation imaging apparatus comprising: a movement control unit that moves the radiation generation unit to a position facing the radiation detection unit based on the position of the radiation detection unit calculated by the calculation unit. Detecting means for detecting a characteristic part of the radiation detecting unit;
The radiation imaging apparatus according to claim 1, wherein the calculation unit calculates the position of the radiation detection unit based on the feature unit detected by the detection unit. The detection means is a plurality of imaging means,
The radiation imaging apparatus according to claim 2, wherein the calculation unit calculates a position of the radiation detection unit based on a plurality of images captured by the plurality of imaging units. The radiation generating unit is supported so as to be swingable with respect to the arm unit,
The radiation detection unit includes an inclination detection unit that detects an inclination of the radiation detection unit,
The movement control means swings the radiation generating unit with respect to the arm unit so as to face the radiation detecting unit based on the inclination of the radiation detecting unit detected by the inclination detecting unit. The radiation imaging apparatus according to any one of claims 1 to 3. Obstacle detection means for detecting obstacles;
Obstacle determining means for determining whether or not there is an obstacle detected by the obstacle detecting means within a range in which the radiation generating unit is moved by the movement control means;
5. The movement control unit restricts movement of the radiation generating unit when it is determined by the obstacle determining unit that an obstacle exists in a range in which the radiation generating unit is moved. The radiation imaging apparatus according to any one of the above.   The radiation imaging apparatus according to claim 5, wherein the obstacle detection unit is a plurality of imaging units that detect the radiation detection unit. A radiation generator for exposing the radiation;
A radiation detection unit that receives and images radiation emitted from the radiation generation unit, and a method for controlling the radiation imaging apparatus,
A calculation step of calculating a position of the radiation detection unit;
And a movement control step of moving the radiation generating unit to a position facing the radiation detecting unit based on the position of the radiation detecting unit calculated by the calculating step. Method. A radiation generator for exposing the radiation;
A program for controlling a radiation imaging apparatus having a radiation detection unit that receives and images radiation emitted from the radiation generation unit,
A calculation step of calculating a position of the radiation detection unit;
A program for causing a computer to execute a movement control step of moving the radiation generation unit to a position facing the radiation detection unit based on the position of the radiation detection unit calculated by the calculation step.

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