WO2015059795A1

WO2015059795A1 - Radioscopic apparatus

Info

Publication number: WO2015059795A1
Application number: PCT/JP2013/078812
Authority: WO
Inventors: 剛高柳
Original assignee: 株式会社島津製作所
Priority date: 2013-10-24
Filing date: 2013-10-24
Publication date: 2015-04-30

Abstract

The control unit (20) is provided with: an automatic brightness control section (21) for controlling the tube current and tube voltage of the X-ray tube (31) so that the brightness of the radioscopic image on the display unit (17) is a target value; a photometric region display section (22) for displaying the photometric region to be used for the automatic brightness control together with the radioscopic image displayed on the display unit; a photometric region position-setting section (23) for setting the position of the photometric region by the operation of an operation unit (18); a photometric region size-modifying section (24) for modifying the size of the photometric region by operation of the operation unit (18); a pixel value-selecting section (25) for selecting a pixel value for creating an automatic brightness adjustment signal by operation of the operation unit (18); and a photometric region-moving section (26) for moving the photometric region when the radioscopic region is moved in the subject.

Description

X-ray fluoroscope

The present invention relates to an X-ray tube for irradiating X-rays, an X-ray detector for detecting X-rays passing through a subject, and X-ray fluoroscopy on a display unit based on the X-rays detected by the X-ray detector. The present invention relates to an X-ray fluoroscopic apparatus including an image processing unit that displays an image.

In such an X-ray fluoroscopic apparatus, automatic luminance control is performed so that an image can always be displayed with an appropriate luminance regardless of the difference in the physique of the subject and the difference in the fluoroscopic part (Patent Literature). 1). In this automatic luminance control, the luminance of the X-ray fluoroscopic image on the display unit is set based on an automatic luminance adjustment signal created by the pixel value of the photometric region among the pixel values of the X-ray detected by the X-ray detector. It is executed by an automatic brightness control unit including an IBS gate circuit for controlling a tube current and a tube voltage with respect to the X-ray tube so as to obtain a value.

In addition, accurate automatic exposure control can be performed by removing lighting fields with extreme variations in contrast or lighting fields with large contrast differences as the lighting fields used to perform automatic exposure control. A possible X-ray image diagnostic apparatus has also been proposed (see Patent Document 2).

JP 2000-261724 A JP 2005-143672 A

In conventional X-ray fluoroscopy devices, the position of the photometric area used for automatic brightness control has been fixed. For this reason, automatic brightness control may not be performed properly depending on the state of the subject performing fluoroscopy and the fluoroscopic position.

FIG. 7 is a schematic diagram showing an X-ray fluoroscopic image of the hand 100 of the subject.

When such a subject's hand 100 is seen through, if a photometric area used for executing automatic exposure control is placed between the subject's fingers, it is irradiated from the X-ray tube. X-rays directly enter the X-ray detector. For this reason, in the automatic brightness control unit, control is performed in the direction of decreasing the tube voltage so that the X-ray fluoroscopic image becomes dark. As a result, there is a problem in that X-rays are not sufficiently transmitted through the muscles and bones of the hand, and those images become excessively dark.

FIG. 8 is a schematic diagram showing an X-ray fluoroscopic image of the hand 100 of the subject wearing the connection tool 101.

In this way, when looking through the hand 100 of the subject to which the metal connector 101 is attached, the photometric area used for executing automatic exposure control is at a position corresponding to the metal connector 101. When arranged, the X-rays irradiated from the X-ray tube hardly enter the X-ray detector. For this reason, the automatic brightness control unit executes control in the direction of increasing the tube voltage so that the X-ray fluoroscopic image becomes brighter. As a result, there arises a problem that the muscles and bones of the hand are completely halated.

FIG. 9 is a schematic diagram showing an X-ray fluoroscopic image near the heart 103 of the subject 102 to which the pacemaker 104 is attached.

Thus, when the vicinity of the heart 103 of the subject 102 to which the pacemaker 104 is attached is seen through, the photometric area used for executing the automatic exposure control is arranged at a position corresponding to the metal pacemaker 104. In some cases, X-rays emitted from the X-ray tube hardly enter the X-ray detector. For this reason, the automatic brightness control unit executes control in the direction of increasing the tube voltage so that the X-ray fluoroscopic image becomes brighter. As a result, there arises a problem that the heart part completely halates.

The present invention has been made to solve the above-described problems, and provides an X-ray fluoroscopy device capable of always displaying an X-ray fluoroscopic image having an appropriate luminance regardless of a part or situation where X-ray fluoroscopy is performed. The purpose is to do.

In the first invention, an X-ray tube that irradiates X-rays, an X-ray detector that detects X-rays irradiated from the X-ray tube and passed through the subject, and X detected by the X-ray detector An image processing unit for displaying an X-ray fluoroscopic image on a display unit based on a pixel value by a line, and an automatic luminance created by a pixel value in a photometric region among pixel values by an X-ray detected by the X-ray detector An automatic luminance control unit that controls a tube current and a tube voltage supplied to the X-ray tube so that the luminance of the X-ray fluoroscopic image on the display unit becomes a target value based on the adjustment signal; In the fluoroscopic apparatus, a photometric area display unit that displays the photometric area together with an X-ray fluoroscopic image displayed on the display unit, and a photometric area position setting that sets the position of the photometric area based on an instruction from an operator A section.

In the second invention, a photometric area size changing unit for changing the size of the photometric area based on an instruction from the operator is provided.

In the third aspect of the invention, based on the operator's instruction, the automatic brightness adjustment signal is created based on the highest pixel value among the pixel values in the photometric area, or based on the average value of the pixel values in the photometric area. A pixel value selection unit that selects whether to generate the automatic luminance adjustment signal or to generate the automatic luminance adjustment signal based on the lowest pixel value among the pixel values in the photometric area.

In the fourth aspect of the invention, a photometric area moving unit is provided for moving the photometric area as the subject's fluoroscopic area moves.

In the fifth invention, the photometric area moving unit stores two positions as the characteristic portions where the amount of change in the pixel value due to the X-rays detected by the X-ray detector is large, and moves the two characteristic portions. The photometric area is moved based on the amount.

According to the first invention, by moving the photometric area displayed on the display unit based on an instruction from the operator, the photometric area is arranged at an appropriate position according to the part to be subjected to X-ray fluoroscopy and the situation. Therefore, it is possible to always display an X-ray fluoroscopic image with appropriate luminance on the display unit.

According to the second invention, by changing the size of the photometric area based on the operator's instruction, it is possible to set the size of the photometric area according to the part to be subjected to X-ray fluoroscopy and the situation. On the other hand, it is possible to always display an X-ray fluoroscopic image with appropriate luminance.

According to the third invention, a pixel value for creating an automatic brightness adjustment signal can be selected based on an instruction from an operator, and an X-ray fluoroscopic image with appropriate brightness is always displayed on the display unit. It becomes possible to do.

According to the fourth and fifth aspects of the present invention, when the fluoroscopic region is moved by moving the photometric region in accordance with the movement of the subject's fluoroscopic region, the display unit always has an appropriate X brightness. A fluoroscopic image can be displayed.

1 is a schematic view of an X-ray fluoroscopic apparatus according to the present invention. It is a block diagram which shows the control system of the X-ray fluoroscope which concerns on this invention. 4 is a schematic diagram showing a display screen displayed on the display unit 17. FIG. 3 is a graph showing a relationship between tube current and tube voltage supplied to an X-ray tube 31. It is explanatory drawing which shows the movement operation | movement of the photometry area | region 92. FIG. It is explanatory drawing which shows the movement operation | movement of the photometry area | region 92. FIG. It is a schematic diagram which shows the X-ray fluoroscopic image of the hand 100 of a subject. It is a schematic diagram which shows the X-ray fluoroscopic image of the subject's hand 100 with which the connection tool 101 was mounted | worn. It is a schematic diagram which shows the X-ray fluoroscopic image of the heart 103 vicinity of the subject 102 with which the pacemaker 104 was mounted | worn.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of an X-ray fluoroscopic apparatus according to the present invention.

This X-ray fluoroscopic apparatus includes an X-ray tube 31 and a flat panel detector 32 as an X-ray detector that detects X-rays irradiated from the X-ray tube 31 and passing through a subject lying on the table 19. A C-type arm 33 for supporting the X-ray tube 31 and the flat panel detector 32, a support part 34 for slidably supporting the C-type arm 33, a turning part 35 for turning the support part 34, and And a support portion 36 that supports the swivel portion 35 in a state of being erected with respect to the floor surface.

An arcuate guide portion 37 is formed on the C-type arm 33, and the support portion 34 is engaged with the guide portion 37 to support the C-type arm 33 so as to be slidable. The C-shaped arm 33 is configured so that the X-ray tube 31 and the flat panel detector 32 are aligned with the X-ray axis extending from the X-ray tube 31 to the flat panel detector 32 being the diameter of the arc forming the guide portion 37. I support it. The swivel unit 35 swivels the support unit 34 along with the C-arm 33 and the like around an axis orthogonal to the X-ray axis extending from the X-ray tube 31 to the flat panel detector 32.

In the X-ray fluoroscopic apparatus having such a configuration, it is possible to execute X-ray fluoroscopy from an arbitrary direction on the subject by sliding and turning the C-type arm 33. The X-ray fluoroscopic image is displayed on the display unit 17 described later.

FIG. 2 is a block diagram showing a control system of the X-ray fluoroscopic apparatus according to the present invention.

This X-ray fluoroscopic apparatus is equipped with a CPU that performs logical operations, a ROM that stores operation programs necessary for controlling the apparatus, a RAM that temporarily stores data during control, and the like, and controls the entire apparatus. The unit 20 is provided. The control unit 20 is connected to the flat panel detector 32 as described above. The control unit 20 is connected to an X-ray tube control unit 30 for controlling a tube voltage and a tube current applied to the X-ray tube 31. Further, the control unit 20 is also connected to a display unit 17 including a liquid crystal display panel for displaying an X-ray fluoroscopic image and an operation unit 18 having an input device such as a mouse and a keyboard.

The control unit 20 includes an image processing unit 29 that displays an X-ray fluoroscopic image on the display unit 17 based on a pixel value by X-rays detected by the flat panel detector 32. This image processing unit 29 has, as a functional configuration, an automatic luminance control unit 21 for controlling the tube current and the tube voltage for the X-ray tube 31 so that the luminance of the X-ray fluoroscopic image on the display unit 17 becomes a target value. , A photometric area display unit 22 for displaying a photometric area used for automatic brightness control together with the X-ray fluoroscopic image displayed on the display unit 17, and photometry for setting the position of the photometric area by operating the operation unit 18 A pixel for creating an automatic brightness adjustment signal by operating the area position setting unit 23, the photometric area size changing unit 24 for changing the size of the photometric area by operating the operating unit 18, and the operating unit 18 A pixel value selection unit 25 that selects a value, and a photometric region moving unit 26 that moves the photometric region in accordance with the movement of the subject's fluoroscopic region.

FIG. 3 is a schematic diagram showing a display screen displayed on the display unit 17.

As shown in this figure, the X-ray fluoroscopic image 91 of the subject's hand is displayed on the display unit 17 as in FIG. In the display unit 17, a photometric area 92 used for automatic brightness control is displayed together with the X-ray fluoroscopic image 91. The photometric area 92 is displayed by the photometric area display unit 22 in the image processing unit 29 of the control unit 20. For example, when the size of the X-ray fluoroscopic image 91 is 1000 pixels × 1000 pixels, the photometric area 92 has a size of about 10 pixels × 10 pixels to 100 pixels × 100 pixels.

The automatic luminance control unit 21 in the image processing unit 29 of the control unit 20 displays on the display unit 17 based on the average value of the pixel values in the photometric region 92 among the pixel values in the X-ray fluoroscopic image 91 displayed on the display unit 17. An automatic brightness adjustment signal for controlling the brightness of the X-ray fluoroscopic image 91 is created. And a command signal is transmitted with respect to the X-ray tube control part 30, and the tube current and tube voltage with respect to the X-ray tube 31 are controlled so that the brightness | luminance of the X-ray fluoroscopic image 91 in the display part 17 becomes a target value.

FIG. 4 is a graph showing the relationship between the tube current supplied to the X-ray tube 31 and the tube voltage. In this figure, the vertical axis indicates the tube current, and the horizontal axis indicates the tube voltage.

The tube voltage and tube current supplied to the X-ray tube 31 are set so as to always have a certain relationship as shown in FIG. The relationship between the tube current and the tube voltage shown in FIG. 4 is stored in advance as a fluoroscopic mode M in X-ray fluoroscopy. When automatic brightness control is executed, the tube current and the tube voltage are controlled according to the fluoroscopic mode M. More specifically, when the luminance of the fluoroscopic image 91 on the display unit 17 is lower than the target value, the tube voltage is increased, and when the luminance of the fluoroscopic image 91 on the display unit 17 is higher than the target value. Reduce the tube voltage. As the tube voltage changes, the tube current changes corresponding to the fluoroscopic mode M shown in FIG.

In addition, when the photometric region 92 is disposed between the subject's fingers when the subject's hand 100 is seen through, the X-rays emitted from the X-ray tube 31 are directly applied to the flat panel detector 32. Since the light enters, the automatic brightness control unit 21 performs control in a direction to decrease the tube voltage so that the X-ray fluoroscopic image becomes dark. For this reason, there is a problem that X-rays are not sufficiently transmitted through muscles and bones, and those images become excessively dark. In such a case, when the operator performs an operation for moving the photometry area 92 using the operation unit 18, the photometry area position setting unit 23 in the image processing unit 29 of the control unit 20 is set to the photometry area. 92 is moved. As a result, automatic brightness adjustment can be properly executed.

When the photometric area 92 is arranged at a position corresponding to the connector 101 shown in FIG. 8 or at a position corresponding to the pacemaker 104 shown in FIG. 9, the light is irradiated from the X-ray tube 31. Since X-rays hardly enter the flat panel detector 32, the automatic luminance control unit 21 performs control in the direction of increasing the tube voltage so that the X-ray fluoroscopic image becomes bright. This causes a problem that the X-ray fluoroscopic image 91 is completely halated. Even in such a case, when the operator performs an operation for moving the photometry area 92 using the operation unit 18, the photometry area position setting unit 23 in the image processing unit 29 of the control unit 20 performs the photometry. The region 92 is moved. As a result, automatic brightness adjustment can be properly executed.

As described above, even when the photometry area 92 is moved, the X-ray tube 31 irradiates in a part of the photometry area 92 depending on the state and the fluoroscopic position of the subject performing X-ray fluoroscopy. X-rays may directly enter the flat panel detector 32, or X-rays emitted from the X-ray tube 31 may not enter the flat panel detector 32. In such a case, the size of the photometry area 92 is further changed.

That is, when the operator performs an operation for moving the photometry area 92 using the operation unit 18, the photometry area size changing unit 24 in the image processing unit 29 of the control unit 20 sets the size of the photometry area 92. change. As a result, automatic brightness adjustment can be properly executed. In this case, as shown in FIG. 3, a drop-down list 93 for changing the size of the photometric area 92 is displayed on the display unit 17 together with the X-ray fluoroscopic image 91. The operator selects the size of the photometric area 92 by operating the drop-down list 93 using a mouse or the like. Instead of the drop-down list 93, an icon or the like for specifying the size may be used.

As described above, even when the photometric area 92 is moved and the size of the photometric area 92 is changed, some areas of the photometric area 92 may be used depending on the state of the subject performing fluoroscopy and the fluoroscopic position. The X-rays emitted from the X-ray tube 31 may directly enter the flat panel detector 32, or the X-rays emitted from the X-ray tube 31 may not enter the flat panel detector 32. In such a case, a pixel value for creating an automatic brightness adjustment signal is further selected.

That is, when the operator performs an operation for selecting a pixel value by using the operation unit 18, the pixel value selection unit 25 in the image processing unit 29 of the control unit 20 creates an automatic brightness adjustment signal. Select a pixel value. For example, when seeing through the hand 100 of the subject, a part of the photometry area 92 is disposed between the fingers of the subject, and the X-rays emitted from the X-ray tube 31 are directly incident on the flat panel detector 32. In this case, the operator uses the operation unit 18 to create the automatic brightness adjustment signal as the pixel value, not the average value of the pixel values in the photometry area 92 but the minimum value of the pixel values in the photometry area 92. Select. That is, an automatic brightness adjustment signal is created based on the lowest pixel value in the photometric area 92. On the other hand, a part of the photometric area 92 is arranged at a position corresponding to the connector 101 shown in FIG. 8 and the pacemaker 104 shown in FIG. 9, and X-rays irradiated from the X-ray tube 31 hardly enter the flat panel detector 32. In some cases, the operator uses the operation unit 18 to set the maximum value of the pixel values in the photometric area 92 instead of the average value of the pixel values in the photometric area 92 as the pixel value for creating the automatic brightness adjustment signal. select. That is, an automatic brightness adjustment signal is created based on the maximum pixel value in the photometric area 92. As a result, automatic brightness adjustment can be properly executed.

In this case, as shown in FIG. 3, the display unit 17 generates an automatic luminance adjustment signal based on the highest pixel value among the pixel values of the photometric area 92 together with the X-ray fluoroscopic image 91, or the photometric area 92 A drop-down list 94 for selecting whether to generate an automatic luminance adjustment signal based on the average value of the pixel values or to generate an automatic luminance adjustment signal based on the lowest pixel value among the pixel values in the photometry area 92 It is displayed. The operator operates the drop-down list 94 using a mouse or the like to select a pixel value for creating an automatic brightness adjustment signal. Instead of the drop-down list 94, an icon or the like for specifying the size may be used.

透 The subject's fluoroscopic region may move during X-ray fluoroscopy. In such a case, if the photometry area 92 is fixed, the automatic brightness adjustment that is properly executed by the above operation may be inappropriate. For this reason, in the X-ray fluoroscopic apparatus according to the present invention, the photometric area 92 is moved by the photometric area moving unit 26 in the image processing unit 29 of the control unit 20 in accordance with the movement of the fluoroscopic area of the subject. Adopted.

5 and 6 are explanatory views showing the movement operation of the photometry area 92. FIG.

In order to correspond to the movement of the subject's fluoroscopic region, the photometric region moving unit 26 changes the pixel value of the X-ray fluoroscopic image 91 displayed on the display unit 17, that is, the X detected by the flat panel detector 32. Two positions where the amount of change in pixel value due to the line is large are stored as feature portions P1 and P2. Then, the photometric area moving unit 26 moves the photometric area 92 based on the movement amounts of the two characteristic portions P1 and P2. When the characteristic parts P1 and P2 move from the position shown in FIG. 5 to the position shown in FIG. 6, the photometric area moving unit 26 determines the X, Y, and X of the fluoroscopic areas based on the movement of these characteristic parts P1 and P2. The amount of movement in the θ direction is calculated. Then, based on the calculation result, the photometric area 92 is moved in the X, Y, and θ directions. As a result, the photometric area 92 is arranged at a position corresponding to a certain area in the X-ray fluoroscopic image 91 even when the X-ray fluoroscopic image 91 moves, and the automatic luminance adjustment signal is always output under a certain condition. It becomes possible to create.

In the above-described embodiment, the present invention is applied to an X-ray fluoroscopy device including a C-shaped arm 33 that supports the X-ray tube 31 and the flat panel detector 32. The present invention may be applied to an X-ray fluoroscopic apparatus having other configurations such as a hanging X-ray fluoroscopic apparatus.

In the above-described embodiment, the operation unit 18 receives an instruction for the operator to move the photometry area 92, an instruction for selecting the size of the photometry area, an instruction for selecting a pixel value, and the like. However, for example, various instructions may be executed by other methods such as voice input.

DESCRIPTION OF SYMBOLS 17 Display part 18 Operation part 20 Control part 21 Automatic brightness control part 22 Photometry area display part 23 Photometry area position setting part 24 Photometry area size change part 25 Pixel value selection part 26 Photometry area movement part 30 X-ray tube control part 31 X-ray Tube 32 Flat panel detector 33 C-arm 91 X-ray fluoroscopic image 92 Photometric area 93 Drop-down list 94 Drop-down list

Claims

An X-ray tube that emits X-rays;
An X-ray detector for detecting X-rays irradiated from the X-ray tube and passing through the subject;
An image processing unit for displaying an X-ray fluoroscopic image on a display unit based on a pixel value by X-rays detected by the X-ray detector;
Based on an automatic luminance adjustment signal created by a pixel value in a photometric area among pixel values of X-rays detected by the X-ray detector, the luminance of the X-ray fluoroscopic image on the display unit becomes a target value. And an automatic brightness control unit for controlling a tube current and a tube voltage supplied to the X-ray tube,
In an X-ray fluoroscopic apparatus comprising:
A photometric area display unit that displays the photometric area together with an X-ray fluoroscopic image displayed on the display unit;
A photometric area position setting unit for setting the position of the photometric area based on an instruction from the operator;
An X-ray fluoroscopic apparatus comprising:
The X-ray fluoroscopy device according to claim 1,
An X-ray fluoroscopic apparatus comprising a photometric area size changing unit that changes the size of the photometric area based on an instruction from an operator.
The X-ray fluoroscopic apparatus according to claim 2,
Based on an operator's instruction, the automatic brightness adjustment signal is created based on the highest pixel value among the pixel values of the photometry area, or the automatic brightness adjustment signal is set based on an average value of the pixel values of the photometry area. An X-ray fluoroscopic apparatus comprising: a pixel value selection unit that selects whether to create the automatic luminance adjustment signal based on a minimum pixel value among pixel values in the photometric area.
The X-ray fluoroscopy device according to claim 1,
An X-ray fluoroscopy device comprising a photometric area moving unit that moves the photometric area as the subject's fluoroscopic area moves.
The X-ray fluoroscope according to claim 4,
The photometric area moving unit stores two positions where the amount of change in the pixel value due to X-rays detected by the X-ray detector is large as a characteristic part, and the photometry based on the movement amount of the two characteristic parts X-ray fluoroscope that moves the area.