JPH0938076A - X-ray system for computed tomography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an X-ray system for computed tomography which can be easily operated by providing the system with a photographic control part which detects a signal suggestive of a state of apnea in which a patient has fallen, from an artificial respirator and sends this detected signal to a device control part. SOLUTION: This X-ray system for computed tomography consists of an X-ray CT device 10, an artificial respirator 20 and a photographic control part 30. The X-ray CT device 10 comprises an X-ray generation part 11, an X-ray detector 12, a detected signal storage part 13, a signal processing part 14, an image display part 15 and a device control part 16. The photographic control part 30 detects a signal suggestive of a state of apnea in which a patient has fallen, from the artificial respirator 20, and at the same time, sends the detected signal to the device control part 16. The device control part 16 controls the device in such a manner that the tomographic image of the specimen is obtained at the time based on the sent signal. Thus the ease of operating the X-ray system for computed tomography is improved and a tomographic image of high image quality is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray tomographic imaging system including an X-ray CT apparatus and a ventilator, and particularly to humans, animals, etc. who have been temporarily apneaed by the ventilator. The present invention relates to an X-ray tomographic imaging system capable of removing a dynamic false image of a tomographic image of a subject by obtaining the tomographic image of the subject with the X-ray CT apparatus.

[0002]

2. Description of the Related Art A conventional X-ray tomography system
It had only a line CT device. The X-ray CT
The device has an X-ray generation unit, an X-ray detector, a detection signal storage unit, a signal processing unit, an image display unit, and a device control unit. The X-ray generation unit generates X-rays, for example, X-rays.
Something like a ray tube device, the X-ray detector receives the X-rays from the X-ray generation unit, which is placed opposite to the X-ray generation unit, and converts it into a detection signal, The detection signal storage unit stores the detection signal obtained by rotating the X-ray generation unit and the X-ray detector around the subject, and the signal processing unit stores the detection signal stored therein. From which the tomographic image of the subject is calculated, the image display unit displays the tomographic image, the device control unit includes the X-ray generation unit, the X-ray detector, the detection signal storage unit, and the It is a unit that controls the signal processing unit and the image display unit, such as a CPU.

In such an X-ray tomographic imaging system, in order to obtain (take an image of) a tomographic image of the subject, the operator gives an instruction to the subject to stop breathing. Either by words or by providing a voice instruction unit in the X-ray CT apparatus, the voice instruction unit gives the instruction to the subject during the imaging. This instruction means that the subject moves due to the breathing of the subject, so that a so-called “blur” in a tomographic image occurs (dynamic false image,
That was to prevent). However, some subjects were unable to comply with these instructions. For example, subjects were unconscious, subjects who could not understand words such as infants and animals. Such an object, especially an unconscious object such as an object carried to a hospital due to illness or an accident, cannot follow the instructions, and therefore when the object is imaged, its tomographic image is displayed. Since the dynamic false image due to respiration of the subject appears, the diagnosis by the tomographic image of the subject is hindered. In addition, such a subject often has weak breathing (called spontaneous breathing) by the subject himself or cannot perform the spontaneous breathing in many cases, and therefore, an artificial respirator is attached to assist the spontaneous breathing. There were many This artificial respirator artificially inhales and exhales air from the subject. Further, it has been known that, when the oxygen concentration of the air inhaled by the artificial respirator to the subject is higher than that of normal outside air, the subject becomes a state in which the subject does not breathe temporarily (called an apnea state). . Therefore, in the conventional X-ray tomography system, when the subject with the artificial respirator is imaged, when the subject is inhaled with the air having a high oxygen concentration and the apnea is entered, In addition, the operator operated the X-ray CT apparatus to take an image.

[0004]

In the prior art, the apnea is performed by the operator visually observing the apnea state of the subject or by monitoring the respiratory waveform of the subject from an artificial respirator. Since the photograph was taken while confirming the state, it was necessary to monitor the state of not being in the apnea state, which is the time when the photographing was stopped, so that there was a problem that the operator was not easy to use. In addition, there is a problem that when the photographing is performed despite the time when the photographing is stopped, the image quality is deteriorated by the dynamic false image. Furthermore, when a tomographic image with the dynamic false image is taken, it means that the imaging has failed and the same site of the subject must be imaged again.
This unsuccessful imaging has a problem that the subject is exposed unnecessarily. Furthermore, there is a so-called spiral X-ray CT apparatus, which is the mainstream of recent X-ray CT apparatuses. This spiral X-ray CT apparatus moves the bed on which the subject is placed in the direction of the central axis of the rotation while the X-ray generator and the X-ray detector rotate, and the X-ray seen from the subject The tomographic image of the subject in a wide range is obtained by photographing the generation unit and the X-ray detector so as to form a spiral orbit. In this spiral X-ray CT apparatus, since an interpolation method is used to calculate a tomographic image of a conventional subject, when imaging fails, a wider range of subjects can be compared with an X-ray CT apparatus that is not a spiral X-ray CT apparatus. Therefore, there is a problem in that the problems of the usability, the deterioration of the image quality, and the unnecessary exposure become more prominent because the photographing must be redone.

The present invention has been made in view of the above problems, and an object thereof is to provide a convenient X-ray tomographic imaging system.

Another object of the present invention is to provide an X-ray tomographic imaging system capable of obtaining a tomographic image with good image quality.

Another object of the present invention is to provide an X-ray tomographic imaging system in which the subject is not exposed to unnecessary radiation.

Furthermore, the X-ray CT apparatus is a spiral X-ray CT.
An object of the present invention is to provide an X-ray tomographic imaging system that is easy to use, has high image quality, and does not expose the subject to unnecessary radiation exposure.

[0009]

The above-mentioned object is to receive an X-ray from an X-ray generator and an X-ray from the X-ray generator which is placed opposite to the X-ray generator so as to convert it into a detection signal. An X-ray detector, a signal processing unit that calculates a tomographic image of the subject from the detection signal obtained by rotating the X-ray generator and the X-ray detector around the subject, and displays the tomographic image. An X-ray CT apparatus including an image display unit, the X-ray generation unit, the X-ray detector, the rotation drive unit, the signal processing unit, and a device control unit that controls the image display unit, and air to the subject. In an X-ray tomographic imaging system including an artificial respirator that artificially inhales and exhales, a signal indicating that the respiration of the subject from the respirator is in an apnea state is detected, and the detected signal is detected. Equipped with a photographing control unit for transmitting the information to the device control unit. Is achieved by the device control unit is controlled to obtain a tomographic image of the subject of the timing based on the transmitted signal.

The apparatus control section is provided with an imaging control section for detecting a signal indicating that the breath of the subject from the artificial respirator is in an apnea state and transmitting the detected signal to the apparatus control section. Since it was controlled to obtain a tomographic image of the subject at the time based on the transmitted signal,
The apnea state of the subject detected by the imaging control unit is rapidly transmitted to the device control unit, and the device control unit captures a tomographic image of the subject based on this signal. Since the subject is imaged without monitoring the respiratory waveform of the respiratory organ, it is possible to provide a convenient X-ray tomographic imaging system.

Further, as soon as the signal is transmitted, the device control section captures a tomographic image of the subject, so that it is possible to provide an X-ray tomographic imaging system capable of obtaining a tomographic image of good image quality.

Furthermore, as soon as the signal is no longer transmitted, that is, when the apnea is no longer present, the device control unit stops the imaging of the tomographic image of the subject, so that the subject is exposed to unnecessary radiation. It is possible to provide an X-ray tomographic imaging system which does not have such a system.

Furthermore, since the device control section executes or stops the imaging of the tomographic image of the subject by the transmission or non-transmission of the signal, X
Even if the X-ray CT apparatus is a spiral X-ray CT apparatus, it is possible to provide an X-ray tomographic imaging system that is easy to use, has high image quality, and prevents the subject from receiving unnecessary exposure.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An X-ray tomographic imaging system according to the present invention will be described with reference to the drawings with reference to the accompanying drawings. FIG.
Is a block diagram showing an embodiment of the X-ray tomographic imaging system of the present invention, FIG. 2 is a block diagram showing the imaging control unit of FIG. 1, and FIG. 3 is a respiratory waveform of an artificial respirator and imaging of a tomographic image. FIG. 4 is a time chart showing the timing, and FIG. 4 is a flowchart showing the steps until the tomographic image is taken by the X-ray tomographic image taking system of the present invention.

First, the structure of the present invention will be described with reference to FIGS. 1, 2 and 3. The X-ray tomographic imaging system of the present invention has an X-ray CT apparatus 10, a respirator 20, and an imaging control unit 30. The X-ray CT apparatus 10 is
X-ray generation unit (XT) 11, X-ray detector (XD) 12, detection signal storage unit (SM) 13, signal processing unit (SP) 14, image display unit (ID) 15, device control unit (CPU) 16 With. The X-ray generation unit (XT) 11 is an X-ray tube device that generates X-rays, and the X-ray detector (XD) 12 is arranged opposite to the X-ray generation unit (XT) 11 with the subject in between.
A detection signal storage unit (SM) 13 receives an X-ray from the line generation unit (XT) 11 and converts it into a detection signal. The detection signal storage unit (SM) 13 includes the X-ray generation unit (XT) 11 and the X-ray detector (XD) 12 as described above. A device that stores a detection signal obtained by rotating around the subject, a signal processing unit (SP) 14 calculates a tomographic image of the subject from the stored detection signal, an image display unit (ID)
Reference numeral 15 denotes a device for displaying this tomographic image, a device control unit (C
The PU) 16 controls the X-ray generation unit (XT) 11, the X-ray detector (XD) 12, the detection signal storage unit (SM) 13, the signal processing unit (SP) 14, and the image display unit (ID) 15. C
PU. The artificial respirator 20 artificially inhales and exhales air from the subject. Imaging control unit 30
Is for detecting a signal from the artificial respirator that causes the subject's breath to be in an apnea state, and transmits the detected signal to the device control unit (CPU) 16. Also,
As shown in FIG. 2, the imaging control unit 30 has an input buffer amplifier circuit (SA) 31, a signal comparator circuit (SC) 32, a time delay circuit (TD) 33, and an AND circuit (AN) 34. It is a thing. Input buffer amplifier circuit (SA) 31
Is for amplifying the respiratory signal from the artificial respirator 20 so that it becomes the level of the input signal of the signal comparator circuit (SC) 32, which will be described later. "Apnea state" when the other input exceeds or does not exceed the input value of one of the above , Which outputs a specific signal value, the time delay circuit (TD) 33 cannot immediately stop the body movement even when the subject becomes apnea. This is for keeping the photograph waiting. This delay time is obtained by measuring the time from the apnea state until the body movement stops by observing the respiratory signal for several cycles and the movement of the subject in advance. Is input to the time delay circuit (TD) 33 as a set value, and the AND circuit (AN) 34 outputs the output of the signal comparator circuit (SC) 32 to one input of the time delay circuit (T).
D) The output of 33 is input to the other and the output is transmitted to the device control unit (CPU) 16. Further, the signal of the ventilator 20 and the timing of imaging by the X-ray CT apparatus 10 will be described with reference to FIG. The breathing signal of the ventilator of FIG. 3 (a) has the horizontal axis of the drawing as time and the vertical axis of the magnitude (voltage value) of the respiratory signal as the first half of the dotted line in the figure where the waveform rises. Is exhalation, the latter half is inhalation,
The part that is falling shows apnea. Further, if the signal input to one of the signal comparator circuits (SC) 32 is below a certain signal level, the threshold value is set as the signal level indicating the "apnea state". The output signal of the signal comparator circuit (SC) 32 of FIG. 3B has a signal level of “0” when the signal of FIG. 3A rises, that is, when the subject is breathing. And output as
When the signal (a) is falling, that is, when the subject is apnea, the signal level is output as "1". The output of the time delay circuit (TD) 33 of FIG. 3C is to output the signal of FIG. 3B as being delayed by the set delay time. The output signal of the AND circuit (AN) 34 of FIG. 3D is the same as that of FIG.
The logical product of (c) is output, and this output is output to the device controller (C
The PU) 16 is made to transmit.

Next, the steps of taking a tomographic image according to the present invention will be described with reference to FIGS. Step. 41 Based on the signal from the ventilator 20, the operator is in a state of breathing at a certain signal level or higher (called a breathing state) as shown in FIG. The signal level to be set is set as a threshold value at one input of the signal comparator circuit (SC) 32. Specifically, the threshold value is set (the threshold value is set) while monitoring the waveform of the respiratory signal of the artificial respirator 20 with an oscilloscope or the like and comparing the body movement of the subject with the signal waveform of the monitor. Step. 42 The operator sets the time from the signal of the ventilator 20 being in an apnea state until the body movement of the subject is stopped to the time delay circuit (TD) 33 as the delay time. In particular,
While comparing the stop of body movement of the subject and the signal waveform of the monitor, measure the relationship between the stop of body movement and the respiratory signal for several cycles,
The maximum time is set as the delay time. (Measurement and setting of delay time). Step. 43 The imaging control unit 30 outputs the respiratory signal from the artificial respirator 20 to the other through the buffer amplifier and the circuit 31 (SA), and outputs the output signal of the signal comparator circuit (SC) 32 and the time delay circuit (TD) 33. "1 (apnea state)" of the output signal of the AND circuit (AN) 34 of the output signal of the above is detected from the breathing signal, and the detected signal is transmitted to the device control device (CPU) 16 (apnea state) Detection and transmission). Step. The device control unit (CPU) 16 controls imaging of a tomographic image of the subject based on the signal transmitted in the previous step. Then, a tomographic image of the subject is obtained (imaging control of the tomographic image). Step. 45 The imaging control unit 30 detects “0 (breathing state)” of the output signal of the AND circuit (AN) 34 that is linked to the respiratory signal from the artificial respirator 20, from the respiratory signal, and outputs the detected signal. The data is transmitted to the device control device (CPU) 16 (detection and transmission of a respiratory state). Step. 46. The device control unit (CPU) 16 controls the stop of capturing the stepped image of the subject based on the signal transmitted in the previous step (stop of capturing).

In the embodiment of the present invention, the photographing control unit 30 which detects that the respiratory signal from the artificial respirator 20 is in an apnea state and transmits the detected signal to the device control unit (CPU) 16 is provided. Provided, device control unit (CPU) 1
6 controls so as to obtain a tomographic image of the subject at a time based on the transmitted signal, so that the apnea state of the subject detected by the imaging control unit 30 can be quickly controlled by the device control unit (CPU) 16 Then, the device control unit (CPU) 16 captures a tomographic image of the subject based on this signal, so that the object of the present invention can be achieved.

[0018]

According to the X-ray tomographic imaging system of the present invention, the apnea state of the subject detected by the imaging controller is promptly transmitted to the device controller, and the device controller based on this signal. To take a tomographic image of the subject,
Since the image of the subject is taken without the operator monitoring the respiratory waveform of the ventilator, it is possible to provide a convenient X-ray tomographic imaging system.

Further, as soon as the signal is transmitted, the device control section captures a tomographic image of the subject, so that it is possible to provide an X-ray tomographic imaging system capable of obtaining a tomographic image of good image quality. Play.

Furthermore, as soon as the signal is no longer transmitted, that is, when the apnea is no longer present, the apparatus control unit stops the imaging of the tomographic image of the subject, so that the subject is exposed to unnecessary radiation. The effect of being able to provide an X-ray tomographic imaging system that does not exist.

Furthermore, since the device control unit executes or stops the capturing of the tomographic image of the subject by the transmission or non-transmission of the signal, X
Even if the X-ray CT apparatus is a spiral X-ray CT apparatus, it is possible to provide an X-ray tomographic imaging system that is easy to use, has high image quality, and does not expose the subject to unnecessary exposure.

[Brief description of drawings]

FIG. 1 is a block configuration diagram showing an embodiment of an X-ray tomographic imaging system of the present invention.

FIG. 2 is a block configuration diagram showing a shooting control unit of FIG.

FIG. 3 is a time chart showing the respiratory waveform of the ventilator and the timing of imaging by the X-ray CT apparatus.

FIG. 4 is a flow chart showing steps until a tomographic image is taken by the X-ray tomographic imaging system of the present invention.

[Explanation of symbols]

 10 X-ray CT apparatus 11 X-ray generation section 12 X-ray detector 13 Detection signal storage section 14 Signal processing section 15 Image display section 16 Device control section 20 Ventilator 30 Imaging control section 31 Buffer amplifier circuit 32 Signal comparator circuit 33 Time delay circuit 34 AND circuit

Claims (1)

[Claims] 1. An X-ray generation unit, an X-ray detector that receives X-rays from the X-ray generation unit, which are arranged so as to face the subject with respect to the X-ray generation unit, and converts the X-rays into detection signals, and these X-rays. Generator and X
A signal processing unit that calculates a tomographic image of the subject from the detection signal obtained by rotating a line detector around the subject, an image display unit that displays the tomographic image, the X-ray generation unit, and the X X-ray CT apparatus including an X-ray CT apparatus including a line detector, the signal processing unit, and a device control unit that controls the image display unit, and an artificial respirator that artificially inhales and exhales air into the subject In the image capturing system, a device for controlling the device is provided, which includes a capturing control unit that detects a signal indicating that the respiration of the subject from the ventilator is in an apnea state and that transmits the detected signal to the device control unit. The X-ray tomographic imaging system is characterized in that the control unit controls to obtain a tomographic image of the subject at a time based on the transmitted signal.