JP3175840B2 - Medical X-ray equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for automatically controlling X-ray conditions in a medical X-ray apparatus, and more particularly, to a method in which a single radiographic examination includes a plurality of series of radiographs. The present invention relates to a medical X-ray apparatus suitable for performing an imaging method in which the thickness of a subject at a target site changes.

[0002]

2. Description of the Related Art In a medical X-ray apparatus, X-ray conditions are automatically controlled in accordance with the condition of a subject in order to improve operability, labor saving and image quality. Or obtaining a proper degree of photographic blackening is essential. Although there is a wide variety of radiographing methods for the X-ray examination, the following description refers to continuous limb imaging in which a plurality of X-ray photographs are continuously taken to obtain a blood vessel image of the limb.

[0003] In the continuous limb imaging method, an angiographic agent is injected into an artery or a vein suspected of having a lesion in order to observe the hemodynamics of the limbs, particularly the blood vessels of the lower limbs, and the blood vessels flow every moment. The process is continuously recorded on an X-ray film. However, the X-ray film for continuous imaging used here has a side of at most about 35 cm, which is considerably shorter than the length of the entire lower limb.
Accordingly, if the positional relationship between the photographic film and the subject is unchanged, only the range of 35 cm on a side can be photographed due to the restriction on the size of the X-ray film.

Therefore, in continuous lower limb photography, as shown in FIG. 2, the subject 1 is moved to change the positional relationship between the photographic film and the subject, or the X-ray tube device 3 is used to photograph the entire lower limb. By moving the X-ray photographing apparatus including the film feeder 4, desired parts are photographed one after another. In such a photographing, when the photographed part is changed by the above-mentioned means, the thickness of the subject changes accordingly, so that in order to obtain the same photographic density, it is necessary to change the photographing conditions each time. Therefore, FIG.
The imaged site-specific imaging tube voltage setter 22 can set arbitrary photographing conditions for each imaging region, as shown in provided, so that can satisfy the above need.

[0005]

In the above prior art, as described above, a photographing tube voltage setting device for each photographing part is used in order to correct the change in the thickness of the subject when the photographing part changes and obtain the same photographic density. 22 are provided, but automatic control of this condition setting is not taken into consideration, and is left to the operation of the operator. The operator operates the imaging tube voltage setting device 22 by estimating necessary X-ray conditions for each imaging region or sequentially estimating a difference in X-ray conditions using somewhere as a reference condition based on experience and intuition. An object of the present invention is to operate an automatic imaging setting for each imaging region in a continuous imaging in which the imaging region changes during a series of imaging as described above, for example, when the body thickness changes. In addition, it is an object of the present invention to improve operability and prevent a failure in photographing due to a poor condition setting.

[0006]

The above object is achieved by providing a subject with X
An X-ray tube for irradiating an X-ray, a bed on which the subject is placed,
Is placed at a position facing the X-ray tube with the bed of
Receives X-ray images transmitted through the subject and continuously captures multiple times
A continuous imaging device for performing continuous imaging, the X-ray tube and the continuous imaging device
Support means for integrally supporting the device, and an imaging area for the subject.
The area is divided into a plurality of imaging regions in advance, and these imaging regions are
Continuous imaging region setting means for continuous imaging,
X-ray line for continuous imaging of multiple divided imaging sites
Means for setting X-ray conditions for a continuous imaging region for setting a condition;
Moving means for supporting means for controlling movement of the holding means, and the bed
Bed moving means for controlling the movement of
Moving means and / or the bed moving means
The plurality of imaging parts of the subject are
In a medical X-ray apparatus that performs imaging under X-ray conditions set by a line condition setting unit, the continuous imaging region X-ray condition setting unit includes:
Set X-ray conditions for fluoroscopy corresponding to the plurality of imaging regions
Fluoroscopic X-ray condition setting means, and a fluoroscopic X-ray condition setting means
According to the X-ray conditions for fluoroscopy set in the step, the plurality of imaging regions
X-ray condition conversion to convert to X-ray conditions at the time of imaging corresponding to
Calculating means and the radiographic X converted by the radiographic X-ray condition converting means.
Line conditions corresponding to the plurality of imaging regions are set in these imaging units.
X-ray condition storage means for each imaging part stored for each position.
In the case of continuous imaging of the plurality of imaging regions,
X-rays corresponding to the plurality of imaging regions are stored in the X-ray condition storage unit.
The line conditions are read out, and the plurality of imaging regions are read using the X-ray conditions.
Is achieved by shooting.

[0007]

According to each of the above-mentioned means, the imaging conditions at each imaging site are obtained from the fluoroscopic X-ray conditions obtained in advance by fluoroscopy.
Convert to the X-ray condition at the time of shadow and store it in the X-ray condition for each imaging part
When a series of radiographing operations are performed, each time the radiographed part is changed, the corresponding radiographing conditions are sequentially retrieved from the storage means, and the operation is performed so as to update the radiographing conditions set before. This eliminates the need for the operator to set conditions that rely on intuition and experience, improves operability, and prevents shooting failures caused by poor condition settings.

[0008]

FIG. 1 is a block diagram showing an embodiment of the present invention. First, the configuration will be described. The bed 2 on which the subject 1 is placed, the X-ray tube 3, and the subject 1
And a continuous photographing device (usually referred to as a film changer) 4 for continuously and continuously photographing X-rays by X-rays transmitted through the bed 2 and X-rays transmitted through the continuous photographing device 4 into visible light. Image intensifier device 5, a photo pickup 6 for converting the intensity of light converted by image intensifier device 5 into an electric signal, and a television camera for capturing an output image of image intensifier device 5 7 and the above X
A function of supporting the ray tube 3, the continuous photographing device 4, the image intensifier device 5, the photo pickup 6, and the television camera 7, and performing a step movement in the head-foot direction of the subject 1 in order to continuously photograph the lower limbs. A supporting device 8 provided, a film changer operating device 9 for setting the number of images to be taken per second and the total number of images taken by the continuous photographing device 4, and a timing for moving the supporting device 8 in order to change the region to be photographed during continuous lower limb photographing; A hand switch 10 for instructing start,
A stage movement control device 11 for controlling the step movement of the support device 8 in the head and foot direction, a fluoroscopic reference luminance signal generator 12 for generating a signal serving as a reference for making X-ray conditions in fluoroscopy appropriate, and A fluoroscopic X-ray condition setting device 13 for comparing an electric signal of the light intensity from the photo pickup 6 with a signal of a fluoroscopic reference luminance signal generator 12 to set an appropriate X-ray condition; A high voltage generator 14 for supplying actual power; a fluoroscopic X-ray condition setting device 1 which is closed during fluoroscopy
A switching unit 15 for transmitting the fluoroscopic X-ray condition signal set by the control unit 3 to the high voltage generator 14, a fluoroscopic condition / radiographic condition converter 16 which calculates an appropriate radiographic condition from the fluoroscopic X-ray condition, A storage device 17 that receives imaging position information from the stage movement control device 11 and stores the imaging conditions obtained by the fluoroscopy condition / imaging condition converter 16 in a corresponding area.
And an imaging X-ray condition setting unit 18 for reading the contents stored in the storage device 17 and setting the X-ray conditions for imaging, and an imaging X-ray condition signal set by the imaging X-ray condition setting unit 18 which is closed during imaging. Switch 19 for transmitting to high voltage generator 14
The continuous photographing device 4 is controlled under the conditions set by the film changer operating device 9, a photographing request signal is output to the high voltage generator 14, and a request signal for step movement in the head and foot direction is sent to the stage movement control device 11. And a film changer control device 20 for outputting the same.

Next, the actual operation will be described. First, the subject 1 is placed on the bed 2, and the X-ray tube 3, the image intensifier 5, and the television camera 7 mounted on the support device 8 are provided.
Is used to position the imaging region. At this time, the movement of the support device 8 in the head and foot direction is performed by the manual stage movement switch 21.
a, 21b. A photographing unit that shoots with this
Perform fluoroscopy on all positions . In this embodiment, the number of moving stages is five, and the distance between the stages is 22 to 28 cm. This is a numerical value determined from the fact that it is sufficient if the entire area of the imaging area, that is, from the lower abdomen to the toes is approximately 1 meter in the case of continuous lower limb imaging. Normally, it is not necessary to perform imaging over the entire lower limb, so that only the desired imaging region needs to be confirmed through fluoroscopy. Here, the light intensity at the time of performing the fluoroscopy is detected by the photo pickup 6, and the electric signal of the light intensity is compared with the signal of the fluoroscopic reference luminance signal generator 12, and the fluoroscopic X
Line conditions are automatically set by negative feedback control.

The fluoroscopic conditions are input to the high voltage generator via the switch 15 and predetermined X-rays are output from the X-ray tube 3. At the same time, the fluoroscopic conditions set by the fluoroscopic condition setting device 13 are input to the fluoroscopic condition / photographing condition converter 16, converted into appropriate photographic condition information in the same subject area, and sent to the storage device 17. A method as shown in the flowchart of FIG. 5 is used as a method for obtaining the imaging conditions from the fluoroscopic conditions. That is, as shown in FIG. 4, an appropriate photographing voltage when photographing is performed with the photographing current and time set in advance from the fluoroscopic conditions is obtained, and the photographing voltage is calculated as a point value based on a logarithmic rate method (point value method). Convert to the corresponding kV. The logarithmic rate method is described as a document, for example, in "Image Engineering for Radiation Engineers" (Uchida / Yamashita et al.), Published by Tsusho Sangyo Kenkyusha.

Based on this point value, the deviation between the set photographing current / time and the above-mentioned reference current / time is represented by k
The V value is modified to set the shooting conditions to be set.
The storage device 17 obtains, from the stage movement control device 11, information on the position at which fluoroscopy is performed at that time as a stage number, and stores the appropriate photographing condition information in an area corresponding to the stage number. Next, using the manual stage movement switches 21a and 21b, the fluoroscopic position corresponding to the imaging region is moved by one stage, and the same operation as described above is repeated.
When attached performed imaging region all parts are desired which results in the proper Naru photographing conditions of each stage which requires photography is stored in the storage device 17.

Next, the supporting device 8 is set to the position where the photographing is first performed by operating the manual stage moving switches 21a and 21b. Further, the number of shots per second and the total number of shots of the continuous photographing device 4, the timing of moving the stage position of the supporting device 8 in order to change the region to be photographed during the continuous photographing of the lower limb, and the moving direction are set by the film changer operating device 9 and the hand switch is set. By operating 10, a series of continuous lower limb shootings is started. Then, a shooting start signal is output from the film changer control device 20 and the stage movement information is output from the stage movement control device 11 to the storage device 17. Is read out and set in the imaging X-ray condition setting device 18. Thus, imaging is performed under appropriate X-ray conditions. When it is time to move the imaging region set in the film changer operation device 9, a stage movement request signal is sent from the film changer control device 20 to the stage movement control device 11. This signal causes the support device 8 to move one step in a predetermined direction. At the same time, the stage position information sent to the storage device 17 is updated, and the shooting condition corresponding to the new stage is read out from the storage device 17, and the shooting X
The line condition setting unit 18 is set.

By repeating the above, a series of continuous lower limb shooting is performed under the automatically set shooting conditions. Further, the photographing conditions for the first stage to the fifth stage obtained by the above procedure are stored in the plural storage units 17 and the photographing conditions for each stage are stored in the storage areas A to N.
By transferring the data to 7a, the desired condition can be called up and set again by the program selection switch 23 when the photographing of the same or almost the same subject is performed again.

[0014]

Effects of the Invention] In the continuous shooting imaging region changes in a series of photographing, photographing conditions at each of the imaging region, the imaging from X-ray condition in perspective when performed in advance fluoroscopy
The imaging X-ray conditions at the time of imaging corresponding to the part are converted and stored in a storage device. When a series of imaging is performed, the imaging X-ray conditions corresponding to the imaging part change each time the imaging part changes. since operates to sequentially updated the Symbol <br/>憶called from device to image capturing conditions set previously, the operator removes the need for condition setting that relied on intuition and experience until now, the operability In addition, it is possible to prevent a photographing failure caused by a defective condition setting.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a schematic diagram of a supporting device, a subject, and a couch showing a unit for moving an imaging part when performing continuous lower limb imaging;

FIG. 3 is a block diagram of a conventional apparatus for continuous lower limb imaging.

FIG. 4 is a conceptual diagram of a method of obtaining photographing conditions from fluoroscopic conditions.

FIG. 5 is a flowchart of a method for obtaining photographing conditions from fluoroscopic conditions.

[Explanation of symbols]

 16 Perspective condition / photographing condition converter 17 Storage device 18 Photographing condition setting device

Claims (1)

(57) [Claims] An X-ray tube for irradiating a subject with X-rays, a bed on which the subject is mounted, and a bed disposed at a position opposite to the X-ray tube with the bed interposed therebetween and penetrating the subject. A continuous imaging device that receives the obtained X-ray image and continuously captures a plurality of times of imaging,
Supporting means for integrally supporting the X-ray tube and the continuous imaging apparatus, and moving means for supporting means for controlling movement of the supporting means
Bed moving means for controlling movement of the bed;
Is divided into a plurality of imaging regions in advance, and this division
Continuous imaging region setting means for setting a region to be imaged;
Set imaging X-ray conditions corresponding to multiple divided imaging parts
Means for setting an X-ray condition for dividing a part to be photographed,
The moving means for the supporting means and the
The bed moving means or one of them is intermittently moved by a predetermined distance.
Intermittent movement control means for moving
Of the part to be imaged is set by the above-mentioned divided part imaging X-ray condition setting means.
Imaging by the continuous imaging device
In a medical X-ray apparatus for shadowing, the output of the continuous imaging apparatus
Visible light converting means for converting X-rays into visible light, and the visible light
Converting the light intensity converted by the conversion means into an electric signal
Electrical signal converting means, and a camera for photographing with the continuous photographing device.
Film number, film feed timing, etc.
Timing for generating the operation timing of the missing movement control means
Generating means, and said continuous imaging region setting means prior to imaging
Appropriate X-ray conditions for fluoroscopy for each imaging region set in
Generation of a reference signal for generating a reference signal
Generating means, an output signal of the electric signal converting means and the perspective
Transparency for controlling so that the signal of the reference signal generating means matches.
Visual control means and fluoroscopic X-ray conditions obtained by the fluoroscopic control means
To obtain appropriate X-ray imaging conditions
Conversion means and timing from the timing generation means
The intermittent movement control means is controlled by a signal,
Receiving an imaging part position signal from the motion control means,
In the rear, the photographing X obtained by the fluoroscopic condition / photographing condition conversion means
Storage means for storing a line condition,
The X-ray imaging condition obtained by the shadow condition conversion means is converted to the continuous imaging unit.
The divided part corresponding to the imaging part set by the position setting means
Set in the radiographing X-ray condition setting means and move intermittently during radiography
Control means for moving the support means and the bed moving hand
Move the step or one of them intermittently for a predetermined distance
X-ray imaging line set by the divisional part imaging X-ray condition setting means
In this case, the imaging region of the subject is connected by the continuous imaging device.
A medical X-ray apparatus characterized by taking images continuously .