JP3651109B2 - X-ray television apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray television apparatus having a last image hold function, and more particularly to a surgical X-ray television apparatus used during an operation such as orthopedic surgery.
[0002]
[Prior art]
The surgical X-ray television apparatus has an X-ray tube device and an X-ray television image apparatus with an image intensifier attached to both ends of the C-arm, and is mounted on a moving carriage via a C-arm holding mechanism. An X-ray apparatus for fluoroscopy that is designed so that the necessary positioning can be performed by the free movement of each part of the apparatus when it cannot be moved, and generally has the configuration shown in FIG.
[0003]
That is, a horizontal arm 23 is supported on the upper end of a support column 22 erected on a movable carriage 21 so as to be movable up and down. A horizontal arm 23 is supported on the horizontal arm 23 and a C arm 24 rotates around the center of curvature. An X-ray tube 27 irradiating a subject (usually a patient) 26 with X-rays is supported at one end of the C-arm 24 and is opposed to the X-ray tube 27 at the other end. A video mechanism consisting of an image intensifier (hereinafter referred to as II) 28 that converts a transmitted X-ray image into a visible image and a television camera (hereinafter referred to as TV camera) 29 that converts the converted visible image into a video signal is attached. The fluoroscopic image captured by the TV camera 29 is displayed on the monitor 30. Reference numeral 31 denotes a camera control unit (hereinafter referred to as CCU).
[0004]
Therefore, this type of device can set (position) the C-arm 24 at an arbitrary position by freely moving each part of the device (up / down / left / right movement and rotation shown in FIG. 2), and the device itself supports the patient. Since it can be moved completely separated from the bed, it has the merit of being able to see through from various directions.
On the other hand, because of the peculiarity that positioning can be performed freely, the perspective direction is not fixed as in the case of a general imaging device. It rotates and cannot display an image (for example, a normal image) in an optimum direction desired by an operator such as a doctor.
[0005]
For example, if the apparatus is arranged on the left side when viewed from the head direction and the fluoroscopic image is displayed as a normal image on the monitor with the X-ray tube being directly under the patient, the apparatus is moved toward the head from this state. If placed, the fluoroscopic image of the monitor is rotated by 90 °, and if placed on the right side, it is further rotated by 90 ° (180 ° from the left side shown in the figure), and the vertical and horizontal directions are reversed with respect to the normal image. become.
[0006]
In the field of fluoroscopic radiography, a normal image (an image of a doctor facing the patient and an image with the head facing upward) is used for interpretation or diagnosis. Therefore, the fluoroscopic image displayed on the monitor is rotated when the device is positioned. This may interfere with interpretation or diagnosis, and may cause misdiagnosis. For this reason, this type of apparatus is provided with an image rotation correction mechanism that makes an image in an optimal direction (for example, a normal image) even if the display fluoroscopic image of the monitor is rotated by the positioning of the apparatus.
[0007]
As shown in FIG. 2, the TV camera 29 is rotatably mounted around the optical axis O of II28 as shown in FIG. 2, and the motor start switch 32 drives the motor 33 to electrically rotate the TV camera 29. There are devices that rotate a display image by electrically rotating a deflection coil in the same manner as the TV camera of FIG.
[0008]
[Problems to be solved by the invention]
However, the conventional mechanism has the following problems.
In other words, in the mechanism for rotating the former TV camera relative to II, in order to correct the image rotation, the display image on the monitor becomes a normal image, and in order to confirm it, the rotation of the TV camera, that is, the rotation of the display image is seen through. It is necessary to do it while performing. During the rotation operation of the TV camera, preparations for surgery or diagnosis are made, and the X-ray irradiation during this time has a problem that the patient and the operator are exposed to useless X-rays.
The latter method of rotating the deflection coil of the monitor is applied to an X-ray television apparatus having a last image hold function.
[0009]
Therefore, in this method, since the deflection coil is rotated so that the reproduced image of the last image stored in the image memory is displayed as a normal image, at this time, the X-ray is cut off and stored in the image memory. The problem of patient and surgeon exposure can be solved because only a short test exposure is required to perform the test, but the character information from the character memory such as the patient name and ID number displayed on the monitor together with the fluoroscopic image is also included. There is a problem that the orientation is changed by rotation and it is difficult to read, and the distortion and linearity of the monitor deteriorate.
[0010]
Furthermore, since only the display image is rotationally corrected to obtain a normal image, when the fluoroscopic image is stored in a video recorder or a magnetic disk, the fluoroscopic image is stored without correcting the direction of the image. There is a problem that it is necessary to perform rotation correction.
Note that the last image hold function does not require a real-time fluoroscopic image by continuous X-ray irradiation because most of the subjects that are fluoroscopically viewed with this type of device during the operation are stationary and does not require extra X-ray exposure to the patient or the like. For example, when the image memory is incorporated and the fluoroscopy is turned off, the final image is held and reproduced and displayed on the monitor as a still image.
[0011]
In view of the above, the present invention performs image rotation correction without giving extra X-ray exposure to a patient and an operator and without rotating character information such as a patient name displayed together with a fluoroscopic image. An object is to provide an X-ray television apparatus that can be obtained.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, in the X-ray television apparatus of the present invention, an image rotating means for rotating a transmitted X-ray image (perspective image) stored in the last image holding means, and its rotation angle are detected. An angle detection unit and a rotation drive unit that rotates the imaging unit based on an angle signal of the angle detection unit are provided.
[0013]
According to such a configuration, the image rotating unit displays the image stored in the last image holding unit so that the reproduced image of the last image holding unit displayed on the monitor is in a predetermined optimum direction (for example, a normal image). The angle detection means detects the rotation angle. The rotation drive means rotates the image pickup means attached to II so as to be rotatable around its optical axis, with the angle signal of the angle detection means.
The rotation stop position of the imaging means is a position where the display image rotated by positioning is rotated and corrected so as to be in the optimum direction (for example, normal image) desired by the operator. A normal image is displayed.
[0014]
Therefore, if the output of the imaging means is stored in a video memory or a magnetic disk, an image whose rotation is corrected in the optimum direction desired by the operator is stored, so that it is not necessary to correct the rotation of the reproduced image.
In addition, since character information such as a patient name and an ID number is generated from the character memory and displayed superimposed with a fluoroscopic image obtained by the imaging means, the character information is displayed without rotating.
Furthermore, since the last image hole image at the time of image rotation correction only needs to know the direction of the image, it does not require resolution. Therefore, since a short test exposure is sufficient to store an X-ray with a small X-ray dose in the last image hold means, the X-ray exposure dose to a patient or the like can be reduced.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of the present invention. Components having the same functions as those in FIG.
In the figure, 1 is a potentiometer for detecting the rotation angle of the TV camera 29, 2 is a camera rotation control circuit, 3 is an image rotation switch, 4 is a rotation angle determination circuit, 5 is an image rotation circuit, 6 is a sub-monitor, M is this implementation In this embodiment, an image memory for storing the last image provided in the CCU 31 is provided. The above-mentioned 3, 4 correspond to the angle detection means in the present invention, and 5 corresponds to the image rotation means in the present invention.
[0016]
In this configuration, first, a test perspective for image rotation correction is performed.
In the test fluoroscopy, the patient 26 is irradiated with X-rays from the X-ray tube 27, the X-rays transmitted through the patient 26 are converted into a visible image by II28, and converted into a video signal of an X-ray transmission image by the TV camera 29. The
This video signal is stored in the image memory M in the CCU 31, and the stored perspective image is displayed on the monitor 30 even after the test perspective (last image hold).
[0017]
Next, the image rotation correction operation will be described.
When the fluoroscopic image stored in the image memory M at the time of the test fluoroscopy is positioned by the apparatus, for example, when the direction of the image is displayed on the monitor 30 in FIG. It is a fluoroscopic image rotated more than that.
After the test fluoroscopy, the sub-monitor 6 also displays a fluoroscopic image in the same direction (rotated) as the monitor 30.
When the image rotation switch 3a or 3b is operated, the contact signal is input to the rotation angle determination circuit 4, and the rotation angle is determined so that the rotation angle increases in proportion to the time during which the switch is pressed.
[0018]
The image rotation circuit 5 rotates the same image as the image memory M initially stored in the image rotation circuit 5 by the angle determined by the rotation angle determination circuit 4, and the image is displayed on the sub-monitor 6. The surgeon operates the image rotation switch 3a or 3b until the display image on the sub-monitor 6 becomes a normal image as shown.
The rotation angle signal from the rotation angle determination circuit 4 is also input to the camera rotation control circuit 2, which drives the motor 33 to rotate the TV camera 29 around the optical axis O of II28. The rotation angle of the TV camera 29 is detected by the potentiometer 1 and input to the camera rotation control circuit 2.
[0019]
The camera rotation control circuit 2 controls the motor 33 and stops the TV camera 29 at a rotation position where the detection signal of the potentiometer 1 matches the rotation angle signal of the rotation angle determination circuit 4.
The rotation stop position of the TV camera 29 is a position that has been rotationally corrected so that the fluoroscopic image rotated by positioning is displayed as a normal image.
In this state, when the fluoroscopy is resumed for surgery or the like, the fluoroscopic image displayed on the monitor 30 becomes the same normal image displayed on the sub-monitor 6 by the image rotation correction. Further, when the positioning is changed, a test perspective is performed and the image rotation correction is performed by the above-described method.
[0020]
The rotation angle determination circuit 4 is reset at the rising edge of the X-ray exposure signal for fluoroscopy after the image rotation correction.
The image rotation circuit 5 interpolates the image information in accordance with the rotation angle signal from the rotation angle determination circuit 4 and rotates the image by known digital processing.
Furthermore, test fluoroscopy is performed to hold the last image of the image used for image rotation correction, and does not obtain an image used for diagnosis or the like. Dose and short-time X-ray exposure are sufficient.
[0021]
Furthermore, character information such as a patient name and an ID number is generated from a character memory (not shown) and synthesized with a fluoroscopic image obtained from a TV camera, so that it does not rotate and can be used on a video recorder or a magnetic disk. Can store an image in the optimum direction (for example, a normal image) desired by the surgeon whose image rotation has been corrected.
Furthermore, although the sub-monitor is used in the embodiment, it can be omitted if the monitor can be switched and connected to the CCU and the image rotation circuit.
[0022]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0023]
(1) There is no useless X-ray exposure for the patient and the operator during image rotation correction.
[0024]
(2) The direction of character information such as patient name and ID number does not change, and monitor distortion and linearity do not deteriorate.
[0025]
(3) A fluoroscopic image corrected for image rotation can be recorded on a video recorder or magnetic disk.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a conventional surgical X-ray television apparatus.
[Explanation of symbols]
1: Potentiometer 2: Camera rotation control circuit 3: Image rotation switch 4: Rotation angle determination circuit 5: Image rotation circuit 6: Sub monitor
21: Mobile trolley 22: Prop
23: Horizontal arm 24: C arm
25: C-arm support part 26: Patient (subject)
27: X-ray tube 28: Image intensifier (II)
29: TV camera 30: Monitor
31: Camera control unit (CCU)
33: Motor O: Optical axis of II

Claims (1)

X-ray irradiating means for irradiating a subject with X-rays, an image intensifier for converting an X-ray image transmitted through the subject into a visible image, and an imaging means for converting a visible image into a video signal. An X-ray television apparatus comprising a last image hold means for rotatably attaching an image intensifier around an optical axis and storing a transmitted X-ray image immediately before the see-through is turned off. An image rotation means for rotating the transmitted X-ray image stored in the image, an angle detection means for detecting the rotation angle, and a rotation drive means for rotating the imaging means based on an angle signal of the angle means. A featured X-ray television apparatus.

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