JP5523722B2 - X-ray diagnostic imaging equipment - Google Patents

Description

  The present invention relates to an X-ray diagnostic imaging apparatus including an X-ray generator and an X-ray detector that are arranged so as to sandwich a bed on which a subject is placed, and in particular, a posture adjustment mechanism for a bed or an X-ray generation unit. And an X-ray diagnostic imaging apparatus capable of adjusting the imaging range of a subject.

  The X-ray image diagnostic apparatus projects X-rays for fluoroscopy or radiography according to the purpose of diagnosis, diagnosis site, and physique so that an X-ray image having an image quality necessary for diagnosis can be obtained with a small exposure dose.

  2. Description of the Related Art Conventionally, an X-ray diagnostic imaging apparatus has been proposed that includes an X-ray generation unit and an X-ray detection unit that are disposed so as to sandwich a bed on which a subject is mounted (see Patent Document 1). In this X-ray diagnostic imaging apparatus, the patient's body position is recumbent, standing, or oblique by moving the imaging unit up and down or up and down and moving the imaging unit in the body axis direction or body axis orthogonal direction of the patient. As a state, it is possible to perform fluoroscopy and imaging of a desired part of the subject.

  Usually, as preparation for imaging, the relative position between the bed on which the patient is mounted and the X-ray generation unit is roughly adjusted, and the relative position is finely adjusted as desired for imaging. And position adjustment of a bed etc. is performed using the machine operation part provided in a bed or a console.

JP-A-9-31471

  In a conventional X-ray diagnostic imaging apparatus, frequent operation of a machine operation unit is required to capture a site of interest such as an affected part in a state intended by the operator, which is an operator's stress. In addition, it is not possible to ignore the point that the fluoroscopic time becomes longer due to the operation of the machine operation unit being difficult to capture the site of interest in the intended state, and the exposure dose of the subject increases.

  The present invention has been made in view of the above circumstances, and can accurately capture a site of interest in a state intended by the operator without requiring operation of the machine operation unit, and thus the exposure dose of the subject and the operation of the operator An object of the present invention is to provide an X-ray diagnostic imaging apparatus that can reduce stress.

In order to achieve the above-described object, in the X-ray diagnostic imaging apparatus according to the present invention, a bed on which the subject is mounted, an arm that holds the X-ray generation unit and the X-ray detection unit in an opposing arrangement so as to sandwich the bed, In an X-ray image diagnostic apparatus including an image display unit that displays an X-ray image generated from transmission X-ray data of a subject and a control system that controls each device, the control system is displayed on the image display unit An average luminance level is obtained for the optimal display position set on the display screen of the fluoroscopic X-ray image, and based on an imaging condition database in which the average luminance level at the optimal display position of the fluoroscopic X-ray image is associated with the imaging condition. after setting an imaging condition Te, wherein the specific position of the fluoroscopic X-ray image on the display screen is Ru is specified, as specified location shooting reflected in the optimum display position of the display screen is performed , Have rows adjustment of relative position between the bed and the X-ray generating unit, characterized in that to execute shooting the X-ray generation unit and the X-ray detector in accordance with the shooting conditions specified.

  According to the present invention, it is possible to accurately capture a site of interest in a state intended by the operator without requiring an operation of the machine operation unit, thereby reducing the exposure dose of the subject and the operation stress of the operator.

1 is a diagram showing an embodiment of an X-ray image diagnostic apparatus according to the present invention. The functional block diagram which shows the control system of the X-ray image diagnostic apparatus of FIG. The flowchart which shows the flow of the automatic brightness | luminance adjustment process performed with the control system of FIG. FIG. 3 is an explanatory diagram of automatic brightness adjustment processing executed in the control system of FIG. 2. The flowchart which shows the flow of the optimal display control performed with the control system of FIG. FIG. 3 is an explanatory diagram of optimum display control executed in the control system of FIG. 2. The flowchart which shows the flow of the optimal imaging | photography control performed with the control system of FIG. FIG. 3 is an explanatory diagram of optimum photographing control executed in the control system of FIG. 2.

  An embodiment of an X-ray image diagnostic apparatus according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram showing an embodiment of an X-ray image diagnostic apparatus according to the present invention.

  The X-ray diagnostic imaging apparatus U of the present embodiment includes a C-arm 3 that fixes and supports the X-ray generator 1 and the X-ray detector 2 facing each other. A bed 4 is provided between the X-ray generator 1 and the X-ray detector 2. The bed 4 includes a top 5 and a support 6 that supports the top 5, and the top 5 is configured to be mounted on the subject P and movable in a required direction such as a vertical direction or a horizontal direction.

  The top plate 5 and the C arm 3 each incorporate a motor M and a position sensor S, and the motor M and the position sensor S are connected to the machine control unit 7. The machine control unit 7 calculates a required driving amount using the sensor information of the position sensor S so that the top plate 5 of the bed 4 and the C-arm 3 have a required positional relationship, or the machine operation unit 8 by the operator. The motor M is controlled according to the operation amount.

  The X-ray generator 1 is connected to the high voltage generator 9 and irradiates the subject P with X-rays corresponding to the X-ray tube voltage applied from the high voltage generator 9. The high voltage generator 9 is connected to the X-ray controller 10 and receives control of the X-ray tube voltage to be applied to the X-ray generator 1 during imaging and fluoroscopy. The X-ray detection unit 2 is, for example, an I.D. I. (Image intensifier), FPD (Flat Panel Detector), etc. are used, and the X-ray which permeate | transmitted the subject P is detected.

  The imaging protocol selection unit 11 includes a keyboard, a mouse, and other operation devices that enable setting of imaging conditions according to imaging conditions, fluoroscopy conditions, and imaging techniques. The imaging protocol display unit 12 displays the X-ray conditions set by the imaging protocol selection unit 11. The image display unit 13 displays various X-ray images such as a fluoroscopic X-ray image or a captured X-ray image of a subject based on a predetermined imaging condition.

FIG. 2 is a functional block diagram showing a control system of the X-ray image diagnostic apparatus U.
The control system 14 of the X-ray diagnostic imaging apparatus U includes a main CPU (Central Processing Unit) 15, a main storage device 16, an imaging protocol recording medium (X-ray condition recording medium) 17, a position storage medium 18, an optimum position estimation unit 19, The imaging condition storage medium 20, the optimum imaging condition estimation unit 21, the image processing CPU 22, the image signal processing unit 23, the image storage medium 24, the luminance control unit 25, and the exposure timer control unit 26 are included.

  For example, the main CPU 15 reads information indicating the relative position between the top 5 of the bed 4 and the X-ray detection unit 2 set in advance from the position storage medium 18 and sends the information on the relative position to the machine control unit 7. The machine control unit 7 calculates a necessary drive amount of the top plate 5 and the C arm 3 from the received relative position, and controls the motor M based on this drive amount.

  In addition, the main CPU 15 performs various imaging conditions (for example, an X-ray tube voltage, an X-ray tube current, an X-ray exposure time, an X-ray exposure time output from the high voltage generator 9) from the main storage device 16 or the imaging protocol storage medium 17. The focal point size of the line generator 1 is read and sent to the X-ray controller 10. The X-ray control unit 10 controls the high voltage generation unit 9 and the like based on the received imaging conditions.

  The optimum position estimation unit 19 is necessary to move the position noted and specified by the operator in the X-ray image area displayed on the image display unit 13 to the optimum display position on the display screen defined in advance. The optimum relative position between the X-ray generator 1 and the top 5 is estimated. The optimum display position is set at the center of the display screen of the image display unit 13, for example.

  The main CPU 15 sends the optimum relative position information estimated by the optimum position estimation unit 19 to the machine control unit 7 instead of the relative position information between the X-ray generation unit 1 and the top plate 5 stored in the position storage medium 18. send. Then, the machine control unit 7 calculates the driving amount of the C arm 3 and the top plate 5 based on the optimum relative position information estimated by the optimum position estimation unit 19 and controls the motor M of the C arm 3 and the top plate 5. . Hereinafter, the relative position adjustment between the X-ray generator 1 and the top 5 based on the optimum relative position information estimated by the optimum position estimator 19 is referred to as “optimum display control”.

  The main CPU 15 sends the relative position information of the position storage medium 18 to the machine control unit 7 in response to the operator's selection, or sends the optimum relative position estimated by the optimum position estimation unit 19 to the machine control unit 7. Either one of them is determined.

  The imaging condition storage medium 20 stores an imaging condition database in which the average luminance level of the X-ray image and the imaging conditions are correlated.

  The optimum shooting condition estimation unit 21 calculates the average luminance level for the optimum display position set on the display screen of the image display unit 13 in advance before the optimum display control is performed, and is registered and calculated in the shooting condition database. The photographing condition corresponding to the average brightness level is estimated as the optimum photographing condition after the optimum display control. This optimum imaging condition is an optimum imaging condition necessary for the X-ray image to have a predetermined average luminance level. The imaging X-ray tube voltage, the imaging X-ray tube current, and the exposure that are output from the high voltage generator 9 are used. It consists of time, the focal point size of the X-ray generator 1 and the like.

  The main CPU 15 sends the optimum imaging conditions estimated by the optimum imaging condition estimation unit 21 to the X-ray control unit 10 instead of the imaging conditions stored in the main storage device 16 and the imaging protocol storage medium 17. The X-ray control unit 10 performs X-ray irradiation by controlling the high voltage generation unit 9 and a built-in exposure timer based on the received optimum imaging conditions.

  The image processing CPU 22 and the image signal processing unit 23 cooperate to signal-process the transmitted X-ray signal that has passed through the subject P received from the X-ray detection unit 2 and generate an X-ray image. Further, the image processing CPU 22 and the image signal processing unit 23 cooperate with each other at the end of at least the photographing condition setting process among the fluoroscopic X-ray images generated during the automatic luminance adjustment of the luminance control unit 25. The fluoroscopic X-ray image is displayed on the image display unit 13, and image data of the fluoroscopic X-ray image is recorded in the image storage medium 24 as necessary.

  The brightness control unit 25 receives an input of a detection signal of transmitted X-rays that have passed through the subject P from the X-ray detection unit 2 so that the brightness of the fluoroscopic X-ray image displayed on the display screen of the image display unit 13 is appropriate. The fluoroscopic conditions (fluoroscopic X-ray tube voltage, fluoroscopic X-ray tube current) are determined (Automatic Brightness Control), and the imaging conditions defined by using the determined fluoroscopic conditions as an index (for example, the X-ray tube) Information related to voltage, imaging X-ray tube current, exposure time of imaging X-rays, focus size of imaging X-ray generation unit 1) is transmitted to the X-ray control unit 10.

  FIG. 3 is a flowchart showing the flow of automatic brightness adjustment processing executed by the control system 14 of the X-ray image diagnostic apparatus U.

  Step S101 is a step of determining whether or not there is an instruction to start fluoroscopy (Yes / No). An instruction to start X-ray fluoroscopy is given by the user, and the process does not proceed to the next step until it is determined to be <Yes> in step S101.

  Step S <b> 102 is a step that is executed when it is determined to be <Yes> in step S <b> 101, and irradiates the subject P with fluoroscopic X-rays based on the fluoroscopic conditions by the initial setting.

  Step S103 is a step of generating a fluoroscopic X-ray image using X-ray image data based on transmitted X-rays that have passed through the subject P.

  Step S <b> 104 is a step of displaying the transmission X-ray image generated in step S <b> 103 on the image display unit 13.

  Step S105 is a step of calculating an average luminance level of the transmission X-ray image generated in step S103 and determining whether or not the average luminance level has reached a set value (Yes / No). For example, the average luminance level is calculated for a predetermined region at the center position of the display screen of the image display unit 13.

  Step S106 is a step that is executed when it is determined to be <No> in Step S105, and changes the fluoroscopic condition. After executing the process of step S106, the process proceeds to step S102. That is, until the determination in step S105 is <Yes>, the processing of step S102 → step S103 → step S104 → step S105 → step S106 is repeated, and fluoroscopic X-rays are applied to the subject P based on the fluoroscopy conditions that are changed as needed. Irradiate.

  Step S107 stores the fluoroscopic condition and the fluoroscopic X-ray image at that time when the determination is made in step S106 as <Yes>, that is, when the average luminance level of the fluoroscopic X-ray image reaches the set value (LIH: Last Image hold).

  Step S108 is a step of determining imaging conditions including the X-ray tube voltage at the time of imaging, using the fluoroscopic X-ray tube voltage as the fluoroscopy condition stored in step S107. FIG. 6 is an explanatory diagram of the automatic brightness adjustment processing. The imaging conditions (for example, imaging X-ray tube voltage, imaging X-ray tube current, imaging X-ray exposure time, imaging X-ray generation unit 1 of the imaging X-ray generator 1 are executed in step S108. It is explanatory drawing of the determination method of (focus size). As shown in FIG. 6, the imaging condition is determined by referring to a table in which the fluoroscopic X-ray tube voltage width (for example, 50 to 70 kV, 70 to 80 kV, 80 to 90 kV) and the imaging condition are associated with each other in step S107. This is done by determining which fluoroscopy voltage width the fluoroscopic X-ray tube voltage at the time of determining <Yes> falls within and selecting an imaging condition.

  The exposure timer control unit 26 receives transmission X-ray detection signals that have passed through the subject P from the X-ray detection unit 2 and integrates the detection signals. The integrated value of the detection signal is used as a control signal for an exposure timer (not shown) of the X-ray control unit 10 that stops X-ray irradiation at the time of imaging when the integrated value of the detection signal reaches a predetermined value.

  FIG. 4 is an explanatory diagram of optimum display control, and FIG. 5 is a flowchart showing the flow of optimum display control executed by the control system 14 of the X-ray image diagnostic apparatus U.

  Step S201 in FIG. 5 is performed when a specific position 30 is specified by the operator in the region of interest 29 included in the fluoroscopic X-ray image 28 on the display screen 27 (FIG. 4). 30 is a step of determining 30. As the fluoroscopic X-ray image 28, the one stored in step S107 in the automatic luminance adjustment processing (see FIG. 3) of the luminance control unit 25 is used.

  The designated position 30 is determined by the main CPU 15. For example, when the operator moves the cursor 31 on the fluoroscopic X-ray image 28 on the display screen 27, the position of the cursor 31 is determined from the X-ray image data. Is done.

  In step S202, the X-ray generator 1 and the top plate necessary for the designated position 30 determined in step S201 to appear at the center position 32 as the optimum display position on the display screen 27 as shown in FIG. 4B, for example. 5 is a step of estimating the optimum relative position of 5.

  Step S203 is a step in which the machine controller 7 drives the C arm 3 and the top plate 5 based on the optimum relative position between the C arm 3 and the top plate 5 estimated in Step S202.

  Here, the separation distance X between the designated position 30 and the center position 32 on the display screen 27 is the drive amount Y of the C arm 3 and the top 5 required for moving the designated position 30 to the center position 32. There is a correlation, and this correlation depends on an image enlargement ratio that depends on the distance between the X-ray generator 1 and the subject P and other proportional constants. For example, the optimum position estimation unit 19 uses the relationship of Y = a · X (a is a proportional constant and can be arbitrarily set), for example, C arm 3 or The driving amount of the top plate 5 may be estimated, and the machine control unit 7 may drive the C arm 3 and the top plate 5 based on the driving amount.

  Step S204 is a step of notifying that when the relative position between the top 5 and the X-ray generator 1 has reached the optimum relative position in step S203.

  FIG. 7 is a flowchart showing the flow of optimal imaging control executed by the control system 14 of the X-ray image diagnostic apparatus U. FIG. 8 is an explanatory diagram of optimum photographing control.

  In step S301, the average luminance level of the optimal display position of the display screen 27 (for example, the central position 32 (see FIG. 6) as the optimal display position of the display screen 27) before performing the optimal display control (steps S201 to S204). Is a step of calculating. This average luminance level is performed by the main CPU 15 or the image processing CPU 22 and is performed for a predetermined pixel area including the optimum display position of the display screen 27.

  Step S302 is a step of estimating the optimum photographing condition using the average luminance level calculated in step S301 as an index, and is performed by the optimum photographing condition estimating unit 21.

  FIG. 8 is an explanatory diagram of the optimum photographing condition estimation process.

  Normal imaging conditions when the optimum display control (see step S201 to step S204 in FIG. 5) is not performed are steps in the automatic brightness adjustment process based on the current relative positions of the X-ray generator 1 and the top plate 5. The one determined by the process of S108 is used.

  On the other hand, as shown in FIG. 8, the optimum imaging conditions when the optimum display control is performed are referred to a table in which “transmission X-ray tube voltage width and average luminance level width” and “imaging conditions” are associated with each other. The imaging conditions corresponding to the current fluoroscopic X-ray voltage stored in step S107 in the automatic luminance adjustment process and the average luminance level calculated in step S301 in the optimal imaging control (the average luminance level at the optimal display position on the display screen 27). Estimated by selection. For example, if the current fluoroscopic X-ray voltage is “60 kV” and the average luminance level at the optimal display position of the display screen 27 is “190”, the optimal imaging condition after performing the optimal display control is the imaging X-ray. It is estimated that the tube voltage is “80 kV”, the imaging X-ray tube current is “250 mA”, the exposure time of the imaging X-ray is “100 ms”, and the focal size of the imaging X-ray generation unit 1 is “Small (small)”. . Note that the correlation information between the average luminance level width and the imaging conditions shown in FIG. 8 is acquired in advance through experiments, stored in the imaging condition storage medium 20 as a database.

  In step S303, the main CPU 15 receives the optimum imaging condition estimated in step S302 from the optimum imaging condition estimation unit 21 and sends it to the X-ray control unit 10 and the exposure timer control unit 26.

  Step S304 is a step of performing imaging based on the optimal imaging condition estimated in step S302 in cooperation with the X-ray control unit 10, the exposure timer control unit 26, and the like. When the optimum display control in steps S201 to S204 is completed, this photographing is performed automatically at the completion timing or in response to a request from the operator.

  Next, the effect of the X-ray image diagnostic apparatus U will be described.

  (1) When the specific position 30 of the X-ray image is specified on the display screen 27 of the image display unit 13, the control system 14 of the X-ray image diagnostic apparatus U specifies the optimal display on the display screen. Adjustment of the relative position between the X-ray generator 1 and the top plate 5 (optimal display control: Steps S201 to S204) is performed so that photographing is performed at a position (for example, the center position 32 of the display screen 27).

  Therefore, the operator can irradiate the target site of the subject with X-rays without operating the machine control unit 7 or driving the C-arm 3 or the top plate 5 and obtain a desired X-ray image. That is, even when it is not easy to accurately capture the target region of the subject as in the examination of the digestive tract or the like, the operator simply designates the target region on the display screen 27 of the image display unit 13 and pays attention to the subject. The site is accurately irradiated with X-rays. As a result, the problem of an increase in the exposure dose of the subject and the operation stress of the operator due to the difficulty in determining the position of the bed 4 or the like is solved.

  (2) The control system 14 of the X-ray image diagnostic apparatus U displays the fluoroscopic X-ray image generated in the imaging condition setting step on the image display unit 13, and a specific position 30 of the fluoroscopic X-ray image 28 is designated. When this is done, the above-mentioned optimum display control is performed. For this reason, the effect of (1) can be acquired, without performing imaging | photography which irradiates a comparatively strong X ray.

  (3) Since the control system 14 of the X-ray image diagnostic apparatus U performs an X-ray image obtained by imaging after performing the optimal display control in advance before performing the optimal display control, the X-ray image diagnosis apparatus U has a predetermined average luminance level. An optimum photographing condition estimating unit 21 that estimates necessary optimum photographing conditions is provided. That is, when the optimal display control is completed, X-ray imaging can be performed immediately and under the optimal imaging conditions without setting the imaging conditions. Therefore, the throughput of diagnosis using the X-ray image diagnostic apparatus is improved.

  (4) The control system 14 of the X-ray image diagnostic apparatus U has an imaging condition storage medium 20 for storing an imaging condition database in which the average luminance level of the X-ray image and the imaging conditions are correlated, and optimum imaging condition estimation Before performing the optimal display control, the unit 21 calculates an average luminance level as the optimal display position of the display screen 27 in advance, and sets the imaging condition registered in the imaging condition database and corresponding to the calculated average luminance level as the optimal imaging condition. To do. For this reason, the effect of (3) can be obtained easily.

  The X-ray diagnostic imaging apparatus according to the present invention has been described based on one embodiment. However, the specific configuration is not limited to the present embodiment, and the gist of the invention described in the claims. Design changes and additions are permitted without departing from the above.

  For example, the optimum display position of the display screen has been set at the center of the display screen, but the optimum position is arbitrarily set.

  Moreover, although the optimal imaging conditions showed the example made into imaging | photography X-ray tube voltage, imaging | photography X-ray tube current, exposure time, and a focus size, it is used in order to control the intensity | strength of X-rays, an irradiation dose, an irradiation range, etc. If it is a thing, it can be the target.

  P ...... Subject, 1 ... X-ray generator, 2 ... X-ray detector, 3 ... C-arm, 4 ... Bed, 5 ... Top plate, 6 ... Support base, 7 ... Machine control , 8 ... Machine operation unit, 9 ... High voltage generation unit, 10 ... X-ray control unit, 11 ... Imaging protocol selection unit, 12 ... Imaging protocol display unit, 13 ... Image display unit, 14 ... ... Control system, 15 ... Main CPU, 16 ... Main memory, 17 ... Shooting protocol storage medium, 18 ... Position storage medium, 19 ... Optimum position estimation unit, 20 ... Shooting condition storage medium, 21 ... ... Optimal shooting condition estimation unit, 22 ... Image processing CPU, 23 ... Image signal processing unit, 24 ... Image storage medium, 25 ... Brightness control unit, 26 ... Exposure timer control unit, 27 ... Image display Display screen, 28 ... perspective X-ray image, 29 ... ... Site of interest, 30 ... Designated position of fluoroscopic X-ray image, 31 ... Cursor, 32 ... Center position of display screen.

Claims (5)

A bed on which the subject is mounted, an arm that holds the X-ray generation unit and the X-ray detection unit facing each other so as to sandwich the bed, and an image display that displays an X-ray image generated from transmission X-ray data of the subject In an X-ray diagnostic imaging apparatus comprising a control system that regulates each unit and each device,
The control system obtains an average luminance level for the optimal display position set on the display screen among the fluoroscopic X-ray images displayed on the image display unit, and calculates the average luminance level at the optimal display position of the fluoroscopic X-ray image. and after the photographing condition is set imaging conditions based on the shooting condition database associated with, the particular location of the fluoroscopic X-ray image on the display screen is Ru is specified, the specified position of the display screen as imaging appearing in the optimum display position is performed, it has rows adjustment of relative position between the bed and the X-ray generating unit, capturing the X-ray generation unit and the X-ray detector in accordance with the imaging conditions set X-ray image diagnosis apparatus characterized by for execution. The control system includes a storage unit that stores the shooting condition database,
The imaging conditions stored in the imaging condition database are such that an imaging X-ray image acquired by imaging after adjusting the relative position between the bed and the X-ray generation unit has a predetermined average luminance level. Necessary shooting conditions,
The X-ray diagnostic imaging apparatus according to claim 1. The control system displays at least one of a plurality of fluoroscopic X-ray images generated while changing the fluoroscopic condition on the image display unit, and when a specific position of the fluoroscopic X-ray image is designated, The X-ray diagnostic imaging apparatus according to claim 1 or 2 , wherein a relative position between a bed and the X-ray generation unit is adjusted. The control system, X-rays image diagnostic apparatus according to claim 3, wherein the displaying selectively said image display unit fluoroscopic X ray image average brightness level has reached the set value. Before Symbol optimal display position, X-rays image diagnostic apparatus according to any one of claims 1 to 4, characterized in that it is set in the center of the display screen.

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