JPH11290309A - X-ray diagnostic system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the exposure of X-rays on an operator to execute some treatment to an object during X-irradiation. SOLUTION: An IVR area is preset for the operator to execute the treatment to the object. When an X-ray tube ball 4 passes through an angle range corresponding to the preset IVR area during one rotation of the X-ray tube ball 4, the X-irradiation is stopped or reduced and only when the tube ball passes through the angle range of from A deg. to B deg. excepting for the IVR area, the X- irradiation is ordinarily performed. Thus, the exposure dose of X-rays on the operator in the IVR area can be remarkably reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray diagnostic apparatus, and more particularly to an X-ray diagnostic apparatus suitable for an operator or a doctor who performs some treatment on a subject during X-ray exposure, when the subject is near the subject.
The present invention relates to a line diagnostic device.

[0002]

2. Description of the Related Art In an X-ray diagnostic apparatus, in addition to leaked X-rays from an X-ray tube, there are many X-rays such as peripheral devices related to X-ray measurement and scattered X-rays generated from a subject. Specifically, it is assumed that no person other than the subject enters the X-ray measurement room during X-ray exposure. However, conventionally, for the purpose of actively enhancing diagnostic performance, dynamic measurement in which a high-density angiographic agent is inserted into a blood vessel of a subject together with X-ray measurement, or X-ray measurement of an infant or the like that is intense and requires some assistance, The doctor or caregiver had to be close to the subject during X-ray measurement.

[0003] In recent years, interventional radiology (hereinafter referred to as IVR) has been widely used in cerebral position means and various surgical treatments.
), There is an increasing number of occasions in which various surgical procedures for performing therapeutic treatments at the same time as measurement image diagnosis are performed, and the need for an X-ray diagnostic apparatus suitable for this IVR has increased. Looking at the actual IVR measurement situation, X
A doctor or the like (hereinafter referred to as an operator) performs various treatments near the subject even during the line measurement, and FIG. 6 shows an example of an IVR treatment using a conventional X-ray CT apparatus.

[0004] As shown in FIG.
With the hand 20 ′, the puncture needle 21 is inserted into the subject 3 lying on the bed in the scanner gantry cover 2 from near the outside of the scanner 1, the tip of the puncture needle 21 reaches the target site of the subject, and the cells of the target site Is extracted.

[0005]

However, the above I
In the VR, since it is necessary to constantly check the positional relationship between the tip of the puncture needle and the target part of the subject, the puncture needle 21 is punctured while being held down with the hand 20 ′ so as to fit within the X-ray beam 6. The hand 20 'of the person 20 is always exposed to the X-ray beam regardless of the rotational position of the X-ray tube 4 and the X-ray detector 7, as shown in FIG. It is a major problem in treatment.

The present invention has been made in view of such circumstances, and provides an X-ray diagnostic apparatus capable of reducing the X-ray exposure of an operator performing some treatment on a subject during X-ray exposure. It is intended to be.

[0007]

In order to achieve the above object, the present invention is to rotate an X-ray source and a detector, which are in a positional relationship facing each other across a subject, while rotating the X-ray source and the detector around the subject. An X-ray diagnostic apparatus that irradiates X-rays from a source and displays an image based on a signal indicating transmitted X-rays of a subject captured by the detector, wherein an arbitrary angle during one rotation of the X-ray source and the detector Treatment space setting means for setting a range as a treatment space for a subject; and stopping or reducing the amount of X-ray irradiation of the X-ray source during a period in which the X-ray source passes through an angle range set by the treatment space setting means. And control means for performing the control.

As shown in FIG. 7, when the operator's hand 20 'is above the subject, the X-ray directly strikes the hand 20' from the X-ray source in the 0 ° direction. It can be seen that the exposure is particularly large when in the predetermined angle range including When the rotation of the X-ray source advances and the X-ray hits the subject for the first time, the attenuated X-ray transmitted through the subject is transferred to the operator's hand 2.
Exposure is extremely reduced because it comes to hit 0 '. Therefore, a treatment space for the operator is set, and when the X-ray source is within a predetermined angle range corresponding to the treatment space, the X-ray exposure of the operator is reduced or stopped by reducing the amount of X-ray irradiation. Only the attenuated X-rays that have passed through are able to achieve a significant reduction in the exposure of the operator.

The treatment space can be set by selecting and specifying a treatment position or a treatment space on a screen on which a subject and a surrounding treatment space are graphically displayed. Further, the setting of the treatment space can be automatically set as described in claim 3. That is, the presence of a foreign substance such as a hand different from the subject can be detected from the image. Therefore, when a foreign object is detected, a treatment space is set based on the position.

A technique for changing the X-ray dose during one rotation of the X-ray source and the detector is known as a smart scan. In this smart scan, the X-ray dose is changed according to the cross-sectional shape of the subject. , The transmitted X-ray dose is kept constant irrespective of the cross-sectional shape of the subject, so that a good image can be reconstructed, and the exposure dose of the operator in the treatment space is reduced as in the present invention. is not.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the X-ray diagnostic apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing the overall configuration of an X-ray diagnostic apparatus according to the present invention, and particularly shows an X-ray CT apparatus.

As shown in FIG. 1, this X-ray CT apparatus comprises:
It mainly comprises a scanner 1, a control device 10, an X-ray high-voltage generator 11, an image processing device 30, and the like.
An X-ray tube 4 and an X-ray detector 7 are arranged in the gantry cover 2 of the scanner 1 in a positional relationship of 180 degrees facing each other. The X-rays generated from the X-ray tube 4 pass through an X-ray compensator incorporated in the X-ray beam compensator 5, and the X-ray beam at which the detector incident X-ray dose at the time of measuring the subject becomes substantially constant. Calibrated to intensity distribution. The X-ray beam is further converted into an X-ray beam 6 whose beam width is limited in the slice direction by an X-ray collimator made of a metal body that blocks X-rays and arranged below the X-ray beam compensator 5. Irradiated.

The X-ray beam 6 passes through the subject 3 lying on a bed (not shown) and is sent to an X-ray detector 7 having a plurality of detection channels in a positional relationship facing the X-ray tube 4. Incident. In some X-ray CT apparatuses, a detector-side collimator that further regulates the incident X-ray beam width is arranged on the front surface of the X-ray detector 7. The X-ray incident on the X-ray detector 7 is converted into a current signal, and the current signal is converted into an electric signal by the detector amplifier 8, and these measured electric signals are converted via the A / D converter 13 into the image processing device 30.
Sent to

The image processing apparatus 30 includes a central processing unit (CPU) 31 for controlling the entire X-ray CT apparatus, an image reconstruction processing circuit 32 for executing an image reconstruction operation, and a magnetic disk 3.
3, an interface 34, a display memory 35, etc.
These are connected to the data bus 36. The image reconstruction processing circuit 32 reconstructs a CT image from data input by scan measurement by a known image reconstruction technique. The reconstructed CT image is sent to the display memory 35 via the data bus 36, displayed on the CRT monitor 37, and stored on the magnetic disk 33 for redisplay and the like.

Here, the entire measurement operation of the X-ray CT apparatus is controlled by a command from the control device 10. By controlling the collimator aperture width, a plurality of X-ray beam widths are set, and the rotation of the scanner 1 and the scanner angle ( Control of the entire scanner measurement, such as setting (referred to as a tilt operation) and control of the output of X-rays under the control of the X-ray high-voltage generator 11 are performed.

Next, a measurement procedure for low exposure IVR according to the present invention will be described. When performing the IVR treatment on the subject shown in FIG.
The case where the region is set as the R region will be described. In this case, the operator sets the X-ray measurement conditions and the IVR region on the console 38 before the measurement. The setting of the IVR area at this time is set using a menu screen displayed on an operation screen for a normal measurement protocol selection. That is, as shown in FIG. 2, the subject and the treatment space around the subject are graphically displayed on the screen, and the angle direction viewed from the subject and the IV defined in advance are determined.
Select the R area on the screen. For example, in FIG. 2, a mark indicating the upper part (0 ° direction) of the subject 3 is selected by an instruction input unit such as a mouse, and when an angle position is selected and designated in this manner, the angle position is changed. A predetermined angle range (for example, ± 45 °) at the center is set as an IVR treatment region.

When the setting of these measurement conditions is completed, C
The PU 31 reads the set measurement conditions and the IVR region, and executes a control procedure corresponding to the measurement conditions in advance by the scanner 1,
The data is transmitted to the control device 10 and the bed, and the actual X-ray measurement is started according to the measurement start instruction of the operator. A scanner rotation angle and X-ray control method that discloses this measurement will be described with reference to FIG. 3 showing a relationship between the scanner rotation angle and X-ray irradiation.

Assuming that the angle at which the X-ray tube of the scanner comes right above the subject is 0 °, the normal CT measurement is 360 °.
Although the X-ray intensity is not changed over one rotation, in the present invention, the IVR region is set in advance in the IVR measurement mode, so that the X-ray tube rotates above the subject as shown in FIG. X-rays are controlled to be OFF in a predetermined angle range (ie, a preset IVR region).

Here, the scanner rotation angle for turning on the X-rays needs to secure an area where half scan measurement, which is well known in CT measurement, is possible, and A ° to B shown in FIG. It is necessary to set the scanner measurement rotation angle up to ° at least at the X-ray beam fan opening angle (α) + 180 ° or more. Further, when the left side direction of the subject is set in the IVR area, the scanner measurement rotation angle is set in a range from A ′ ° to B ′ ° as shown in FIG.
X-rays are turned ON only in this range.

Next, the difference between the X-ray control sequence of the present invention and the conventional X-ray control sequence will be described with reference to the timing chart of FIG. In FIG. 4, the vertical axis is ON / O of X-ray.
The FF state is shown, and the horizontal axis shows the scanner rotation angle. FIG. 4A shows a conventional CT measurement mode.
In the T measurement mode, the scanner rotation angle is 360 ° (36 °).
When all the X-rays are irradiated (including 0 ° or more) and the measurement of one cross section is completed, the X-ray is turned off and the bed is moved to the next cross-sectional position, and this is repeated to complete a series of measurements. FIG. 4C shows another CT measurement mode. In this CT measurement mode, the bed is moved simultaneously with the rotation of the scanner or the X-ray is continuously emitted without moving the bed to measure a plurality of times. .

FIGS. 4B and 4D show an IVR measurement mode of the present invention corresponding to the modes shown in FIGS. 4A and 4C. As shown in FIGS. 4B and 4D, the scanner measurement rotation angle is in a range from A ° to B °.
X-rays are ON only in this range. In the present invention, the measurement mode without moving the bed shown in FIG. 4D is assumed. However, it is needless to say that the exposure dose can be reduced in another measurement mode in which an assistant is present near the subject and the measurement is performed. No.

FIG. 5 is a timing chart showing another embodiment in which X-rays are not completely turned off in the IVR region. That is, the embodiment shown in FIG. 3 and FIG.
X-rays are completely O during a predetermined angular range of 360 °.
Although applied to half-scan measurement that can be set to FF, X-rays cannot be completely turned off in full-scan measurement using data of all angles from 0 ° to 360 °.

Therefore, in the case of full scan measurement, as shown in FIG. 5, the IVR regions (0 ° to A ° and B ° to 360 °) are used.
°) to reduce the X-ray dose without completely turning it off. FIGS. 5A and 5B show an embodiment in which the X-ray dose is changed corresponding to the mode of FIG.
(C) and (d) show an embodiment in which the X-ray dose is varied corresponding to the mode of FIG. 4 (c). Thus I
Even when the X-ray dose is reduced in the VR region, the radiation dose to the operator can be significantly reduced.

The way of changing the X-ray dose is not limited to this embodiment. Although the case where the X-ray dose is varied has been described, the X-ray tube voltage may be reduced to reduce the amount of X-ray irradiation. An X-ray reduction filter (such as an aluminum plate or a copper plate) may be inserted at the X-ray beam passing point of No. 5 to lower the intensity of the X-ray beam irradiated on the subject.

The setting of the IVR region is not limited to this embodiment, and an arbitrary angle range may be set by using, for example, a dial. Further, the IVR region can be automatically set. In this case, it is determined from the reconstructed image whether or not a foreign matter (a hand, a treatment tool, or the like) other than the subject exists in the treatment space around the subject. When the presence of the foreign matter is determined, the foreign matter is determined. Detect the position of. Then, based on the detected position of the foreign matter, a predetermined space containing the foreign matter is set to IV.
Set as an R area.

Further, in this embodiment, the present invention is applied to X
The description has been given of the case where the present invention is applied to the X-ray CT apparatus. However, the present invention is not limited to this, and an image intensifier or the like is used as a detector. The present invention is also applicable to an X-ray apparatus that captures a transmitted X-ray image of a user and outputs an image signal indicating the transmitted X-ray image to a monitor to reproduce the image signal. Note that the transmitted X-ray image reproduced by this device is recognized as a stereoscopic image by the afterimage effect of the human eye because the imaging angle changes every moment.

[0027]

As described above, according to the X-ray diagnostic apparatus of the present invention, the X-ray dose is reduced or stopped during the period when the X-ray source passes through the predetermined angle range corresponding to the IVR treatment space. Therefore, it is possible to reduce the X-ray exposure of the operator performing the IVR procedure during the X-ray exposure.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an X-ray diagnostic apparatus according to the present invention.

FIG. 2 is a diagram illustrating an example of a display screen when an IVR area is set on the screen;

FIG. 3 is a diagram illustrating a relationship between a scanner rotation angle and X-ray irradiation ON / OFF based on an IVR region setting.

FIG. 4 is a diagram showing a scanner rotation angle and X-ray ON / OF.
6 is a timing chart showing an F control sequence.

FIG. 5 is a timing chart showing a variable control sequence of a scanner rotation angle and an X-ray.

FIG. 6 is an explanatory diagram showing an example of an IVR treatment using a conventional X-ray CT apparatus.

FIG. 7 is an explanatory diagram showing a positional relationship between an IVR region and an X-ray beam.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Scanner 2 ... Scanner gantry cover 3 ... Subject 4 ... X-ray tube 5 ... X-ray beam compensator 6 ... X-ray beam 7 ... X-ray detector 8 ... Detector amplifier 10 ... Control device 11 ... X-ray high voltage generation Device 20: surgeon 20 ': surgeon's hand 21: puncture needle 30: image processing device 38: console

Claims (3)

[Claims] 1. An X-ray source and a detector having a positional relationship facing each other across a subject are rotated about the subject, and X-rays are emitted from the X-ray source, and the subject is captured by the detector. An X-ray diagnostic apparatus that displays an image based on a signal indicating transmitted X-rays of: a treatment space setting unit that sets an arbitrary angle range during one rotation of the X-ray source and the detector as a treatment space of a subject; Control means for stopping or reducing the amount of X-ray irradiation of the X-ray source during a period in which the X-ray source passes through the angle range set by the treatment space setting means. Diagnostic device. 2. An X-ray source and a detector having a positional relationship facing each other across a subject are rotated about the subject, and X-rays are emitted from the X-ray source, and the subject is captured by the detector. An X-ray diagnostic apparatus that displays an image based on a signal indicating transmitted X-rays, wherein an arbitrary angle range during one rotation of the X-ray source and the detector is set as a treatment space for a subject. A treatment space setting means for setting a subject and a surrounding treatment space by selecting and specifying a treatment position or a treatment space on a screen on which a graphic display is provided; and the X-ray source is set by the treatment space setting means. An X-ray diagnostic apparatus, comprising: control means for stopping or reducing the amount of X-ray irradiation from the X-ray source during a period of passing through the angle range. 3. An object obtained by rotating an X-ray source and a detector, which are in a positional relationship facing each other across a subject, about the subject, irradiating X-rays from the X-ray source, and capturing the subject with the detector. An X-ray diagnostic apparatus that displays an image based on a signal indicating transmitted X-rays of the X-ray source and a detector that detects a position of a foreign substance present in a treatment space around a subject from the image. Treatment space setting means for setting a certain angular range during one rotation as a treatment space for a subject, wherein treatment space setting for setting a space including the foreign matter as the treatment space based on a position of the foreign matter detected by the detection means. Means, and control means for stopping or reducing the amount of X-ray irradiation of the X-ray source during a period in which the X-ray source passes through an angle range set by the treatment space setting means. Line diagnostic equipment.