JPH09220220A - X-ray diagnostic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the danger of a patient even when a bed is suddenly stopped. SOLUTION: A gain controller 44 is provided with an A/D converter(A/D) 45, a read only memory(ROM) 46 and a D/A converter(D/A) 47. The A/D 45 detects distance output between the present position of the bed or the like and a limit point which is an analog signal and converts it to a digital signal and the ROM 46 registers a numerical value (digital data) to be outputted for power assistance by the distance of the component (for instance, the case of buffering with the bed is assumed depending on the attachment angle of a supporting device for hanging an image receiver from a ceiling) of this X-ray diagnostic device to be the object of the buffering of the bed beforehand. The D/A converter 47 converts the numerical value to the analog signal and outputs a power gain. By making the output of the power gain smaller as the limit point is approached, the operator is made to recognize that the limit point is approached.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a plurality of beds each of which has a bed on which a subject is laid down and a support portion which supports an X-ray tube and an imaging apparatus, and which enables an operator to move the bed or the support portion. The present invention relates to an X-ray diagnostic apparatus comprising a moving means and a power assisting means for giving at least one of the moving means a power assisting amount for supporting the movement, and particularly, the moving means is at the limit point. The present invention relates to a technique of an X-ray diagnostic apparatus that allows an operator to recognize that a person is approaching.

[0002]

2. Description of the Related Art Medical X-ray fluoroscopes such as an X-ray fluoroscope and a circulatory system have become indispensable in the field of diagnosis, but recently they have been used not only for diagnosis but also for treatment. It is like this. This is under fluoroscopy,
For example, it is carried out by inserting a catheter with various instruments attached to the tip into a subject, and specifically, expansion of a closed blood vessel, injection of a drug into an organ, etc. It is rapidly spreading because it has the great merit that it can reduce the pain to the subject to the treatment by various kinds of surgery and the treatment can be performed at low cost.
Such treatment is performed by IVR (InterVentional Radiology)
is called. FIG. 4 shows an example of a medical X-ray fluoroscope. A subject 6 is lying on a bed 4 supported by a supporting portion 2 installed on the floor 1. The subject 6 is irradiated with X-rays from the X-ray tube 8, and the fluoroscopic X-ray is an image receiving device (a typical one is an image intensifier.
I. (Hereinafter abbreviated as “”) and is converted into an electric signal. X-ray tube 8 and I.D. I. The arm 10 is supported by an arm 12, and the arm 12 is supported by a carriage 14. Further, the carriage 14 is supported by rails 16 laid on the ceiling 22. The electric signal is displayed as a perspective image of the subject 6 on the display 18 supported by the support device 20 from the ceiling 22 by an image processing device (not shown). X-ray tube 8 and I.D. I. The movement of 10, the movement of the bed, and the ON / OFF of the X-ray can be operated by a console (not shown).

The operation of each component in this apparatus will be described. This apparatus is an apparatus that mainly performs a contrast inspection of blood vessels such as the heart, the head, or the abdomen. In this contrast examination, for example, a catheter is inserted into a subject having a heart disease through a femoral vein or the like, and the progress is confirmed by X-ray fluoroscopy while confirming the progress on a display. In particular, in the heart and the head, it is difficult to grasp a complicated blood vessel running state only by obtaining a fluoroscopic image from one direction in order to selectively advance a blood vessel for advancing a catheter. Therefore, the fluoroscopic images of the same site are obtained from a plurality of directions to confirm the running of blood vessels. Also, in order to enlarge or reduce the field of view of the part being photographed, the I.D. I. Adjustments are made to bring 10 closer to or farther away from the subject's site. Further, in the case of this apparatus, not only the imaging system in which the X-ray fluoroscopic image is supported by the support portion 12 but also the I. I. When
It can be obtained by another imaging system consisting of an X-ray tube. Such another imaging system can rotate in a direction parallel to the body axis of the subject 6, and imaging from a direction that cannot be obtained by the imaging system supported by the support unit 12. Is possible. On the other hand, the bed 4 can be moved in the body axis direction of the subject 6, and the height from the floor 1 can also be changed. This device adjusts the subject 6 to these imaging systems from multiple directions by adjusting a support, an imaging system, another imaging system, and a bed, and selects a target blood vessel from complicated blood vessels. doing. A foot switch 24 is used as a switch for starting the fluoroscopy. Such an inspection is generally performed by injecting a contrast agent through a catheter after the positioning is completed, film-taking the film with, for example, a cine camera 3, and clearly displaying only the blood vessel portion. By the way, in the IVR, after the operator diagnoses the affected part of the subject, the catheter is moved into the blood vessel to the affected part which is aimed from the X-ray fluoroscopic image performed at that time. Therefore, the role of the X-ray fluoroscopic image for moving the catheter to the affected area is very important. Therefore, it is necessary to sequentially capture the X-ray fluoroscopic images while tracking the catheter, and to move the catheter finely in the vicinity of the affected area. However, the bed currently used for laying down the subject is difficult to move finely with a mobile bed, and with a manual bed, the bed is moved to a desired position due to the weight and inertial force of the patient. There was a problem that it was difficult. Therefore, an operator manually changes the position of the bed and detects the changed position of the bed, a force detection unit that detects an operation force generated in the bed, and a motor that drives the bed. And a support control unit for returning the detected position and force to the motor control system so as to support the operating force of the operator. A control method called power assist, which can be moved with a slight force without being affected, is developing.

Next, this power assist will be described with reference to FIG. FIG. 5 is an example of a sequence chart when the bed is power assisted. First, FIG.
Explain the symbol. KC31 is force gain, KX32 is position gain, KV33 is velocity gain, Ki34 is velocity integral gain, KP35 is D / A conversion constant, KE36 is back electromotive force constant, L37 is inductance, R38 is resistance, K
T39 is the torque constant, J40 is the load moment of inertia, D
Reference numeral 41 is a viscous friction coefficient, and 1 / (Js + D) 42 is a motor load. When the operator moves the bed, the force input Td43 at that time is input to the terminal between KT39 and 1 / (Js + D) 42. This input signal is added to the output from KT39 and added to 1 / (Js + D) 42 as a load. The motor drives according to this load. The drive output of this motor is KC which is a force target value by force feedback.
Return to 31. In order to allow the operator to manually move the bed 4 with a slight force, the KC 31 takes charge of movement related to the weight of the subject and the weight of the bed, and manually moves the KC 31. The operator gives a force to the bed 4 to instruct only the direction. Further, in KC31 and KX32, it is calculated so that control can be performed based on the returned detection value so that the force applied by the operator becomes approximately the same so as to approach the force target value or the position target value. The power assist enables the operator to quickly position the bed 4 on which the subject lies down. Moreover, the power assist was also adopted for the support portion 12 shown in FIG.

[0005]

In the above-mentioned prior art, when the subject is laid on the bed 4 and moved, if the bed 4 is advanced beyond the movable range, the direction of the movable range is mechanically changed. There is a case where the bed 4 suddenly stops due to the immovable state, and the subject may move due to the inertial force caused by the sudden stop. When a catheter is inserted into the subject, this movement causes the subject to move. There was a problem that there was a risk of damaging the internal tissues of the.

A method in which the operator recognizes the limit of the movable range by attaching an alarm device is also conceivable. However, in many cases, if the speed of movement of the bed 4 is too fast, it is not possible to deal with it.
There is a problem that it is troublesome for an operator who mainly wants to gaze at the X-ray fluoroscopic image to be careful of the alarm device.

[0007] Further, when performing IVR, the operator needs to keep a close eye on the X-ray fluoroscopic image. Therefore, the operator does not pay attention to the movement of the bed and the supporting portion, and the operator moves the bed to the limit point. There was a problem of fear.

In addition, when the support portion moves, when it suddenly stops at the end of the movable range repeatedly, the X-ray tube attached to the support portion and the I.V. I. Play occurs in the X-ray tube and the I.D. I. There is a problem in that the positional relationship causes a slight deviation, and the reliability decreases due to this deviation.

It is an object of the present invention to provide an X-ray diagnostic apparatus that solves the above problems.

[0010]

The above-mentioned object is provided with a bed on which a subject is laid down and a supporting portion for supporting an X-ray tube and an imaging apparatus, and an operator can move the bed or the supporting portion. In an X-ray diagnostic apparatus comprising a plurality of moving means and a power assisting means for giving at least one of these moving means a power assisting amount for assisting the movement, the power assisting means comprises: Detecting means for detecting a distance from at least one limit point at an end of a predetermined movable range of the means to a point at the current position of the moving means, and adjustment for adjusting the power assist amount based on the distance. It can be achieved by having means.

According to the operation of the present invention, the detecting means detects at least one limit point at the end of a predetermined movable range of the moving means as a distance to the current position of the moving means, It can be recognized that the adjusting means adjusts the power assist amount based on this distance so that the moving means that is closer to the limit point becomes hard to move. Further, in the vicinity of the limit point, it is possible to slowly stop instead of the conventional sudden stop.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an X-ray diagnostic apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a sequence chart example when power assisting a bed of the present invention, FIG. 2 shows a configuration example of the gain controller of FIG. 1, and FIG. 3 is a current position of the bed and a distance to a movable limit. The relationship between (hereinafter simply referred to as "distance") and the operating force and the force gain is shown as a graph.

First, regarding the configuration of the X-ray diagnostic apparatus, the duplicated portions of the conventional technique will be omitted, and only the characteristic features of the present invention will be described. The sequence block when power assisting the bed 4 is, as shown in FIG. 1, a force gain KC31, a position gain KX32, a velocity gain KV33, a velocity integral gain Ki34, a D / A conversion constant KP35, a back electromotive force constant KE36, and an inductance. L
37, resistance R38, torque constant KT39, load inertia moment J40, viscous friction coefficient D41, motor load 1 /
Each block includes a (Js + D) 42 and a gain controller 44. Here, the description of the configuration of the above-mentioned blocks excluding the gain controller 44 has been given in the prior art, so the description thereof will be omitted here.
Only the configuration of the gain controller 44 will be described.

As shown in FIG. 2, the gain controller 44 has an A / D converter (A / D) 45, a read-only memory (ROM) 46, and a D / A converter (D / A) 47. ing. A / D 45 detects the distance output which is an analog signal and converts it into a digital signal, ROM 46
Is assumed to be a component of the X-ray diagnostic apparatus that is the object of buffering the bed (for example, as shown in FIG. 5, the image receiving apparatus 10 buffers the bed 4 depending on the mounting angle of the support 12 hung on the ceiling. The numerical value (digital data) to be output as the power assist amount is registered in advance according to the distance of (Yes), and the D / A 47 converts this numerical value into an analog signal and outputs it to the force gain 31. Further, the ROM 46 stores data corresponding to the waveform as shown in FIG. The address input to the ROM 46 generates data at the following points. Point A is a movement start point of the bed 4, point B is a limit point, point C is an action point at which the power assist amount is maximized, and point D is a reaction point at which the power assist force begins to decrease. In addition, as a method of sensing the distance, a transmitter that emits radio waves or light, a first receiver that is attached to a bed while receiving the radio waves from the transmitter, and the receiver that is placed at a limit point It is assumed that the same second receiving unit is provided and the distance between the first receiving unit and the second receiving unit is sequentially measured. As a means for detecting the distance, the point before the operator moves the bed 4 (corresponding to point A) is 0 volt, and the point immediately before the limit point (corresponding to point B) is Vm volt. , It is assumed that points A to B are linearly proportional.

Next, the operation of the present invention will be described with reference to FIGS. When the operator now moves the bed 4, a certain movement start point of the bed 4 is associated with the point A in FIG. After the operator moves the bed 4 from the position corresponding to the point A, the operation force when the operator moves the bed 4 is gradually reduced as shown in FIG. The amount of power assist is gradually increased as shown in FIG. Then, when the position corresponding to the position corresponding to the point C is reached, the operating force of the operator becomes minimum and the amount of power assist becomes maximum. That is, the operator can move the bed 4 with a slight force. Then, if the bed 4 is moved as it is, if the bed 4 reaches a point D (for example, 50 mm before the point B) that is a predetermined distance before the point B corresponding to the distance that is supposed to buffer the image receiving device 10. For example, gradually reduce the amount of power assist. Therefore, in order for the operator to move the bed 4, it is necessary to increase the operating force of the operator to move the bed 4. In this way, the surgeon can recognize that the limit is about to be reached.

With the above-mentioned structure, the distance to the bed is limited to a range where the detecting means buffers the elements of the X-ray diagnostic apparatus other than the bed. Is detected and the adjusting means adjusts the power assist amount when the limit point is approached, so that, for example, the moving speed of a bed that is being manually moved becomes slower as it approaches the limit point. Can be stopped.

Further, since it becomes possible to recognize that the subject is approaching the limit point due to the difficulty of moving the bed, the operator can gaze at a medical image such as an X-ray fluoroscopic image.

Further, when the present invention is applied to the supporting device, the supporting device can be stopped quietly, so that the rattling can be prevented and the reliability can be improved.

The embodiment of the invention described above includes a bed and an I.D.
I. Has described an example of buffering, but if buffering does not occur, for example, I.D. I. When considering moving to the opposite side of the direction, even if there is no buffer, the movable range of the bed is set to stop at a predetermined position. Included in the present invention.

Although the bed has been described as an example, the I.D. I.
It may be applied to any of the components of the X-ray diagnostic apparatus that can be moved by the operator.

In addition, the first and second receivers are provided,
Although the measurement of the distance between the receivers is taken as an example, the coordinate points of the limit points are stored in the memory as (X, Y, Z), and the coordinate points of the receivers attached to the bed are (x, y). , Z) are sequentially detected to obtain ((X−x) 2+ (Y−y) 2+ (Z
-Z) 2) It is also possible to use a distance for calculating 0.5.

It goes without saying that the present invention can achieve the objects of the present invention, no matter how the above-described embodiments are combined.

[0023]

Since the present invention has the above-mentioned structure, it has an effect that the moving means can be stopped safely.

Further, since it becomes difficult for the operator to move the bed, the operator can recognize that he is approaching the limit point, and the operator can concentrate on gazing at the image. There is an effect of improving.

Further, since it is possible to quietly stop at the end of the movable range of the support, the X-ray tube attached to the support and the I.V. I.
Since the positional relationship of is not likely to be misaligned, the reliability is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a power assist sequence chart of an X-ray diagnostic apparatus of the present invention.

FIG. 2 is a block diagram showing a configuration example of a gain controller in FIG.

FIG. 3 is a graph showing the relationship between the operator's operating force and the magnitude of force gain with respect to the bed position.

FIG. 4 is a diagram showing a configuration example of an X-ray diagnostic apparatus according to the related art and the present invention.

FIG. 5 is a diagram showing an example of a power assist sequence chart of a conventional X-ray diagnostic apparatus.

[Explanation of symbols]

 44 Gain Controller 45 A / D Converter (A / D) 46 Read Only Memory (ROM) 47 D / A Converter (D / A)

Claims (3)

[Claims] 1. A plurality of moving means, each of which has a bed on which a subject is laid down and a support portion which supports an X-ray tube and an imaging apparatus, and which enables an operator to move the bed or the support portion, and a plurality of moving means. In an X-ray diagnostic apparatus comprising: a power assist unit that gives a power assist amount for supporting the movement to at least one of the moving units, the power assist unit is capable of a predetermined movement of the moving unit. A detection unit that detects a distance from at least one limit point at the end of the range to a point at the current position of the moving unit; and an adjusting unit that adjusts the power assist amount based on the distance. X-ray diagnostic device. 2. The X-ray diagnosis according to claim 1, wherein the limit point is a point at a position immediately before the moving means buffers the components of the X-ray diagnostic apparatus except the moving means. apparatus. 3. The X-ray diagnostic apparatus according to claim 1, wherein the adjusting unit reduces the power assist amount as the distance becomes smaller.