JPH0549642A - Ultrasonic endoscope - Google Patents

Abstract

PURPOSE:To monitor the irradiating quantity in a real time, and to give inform ation related to safety to an operator by providing a means for detecting a first echo signal from a tip cap and a deciding means for deciding the irradiating quantity of an ultrasonic beam. CONSTITUTION:To an ultrasonic vibrator 1, a cap first echo detecting part 7 is connected, a first echo of the tip cap is detected and prescribed amplification is executed. Also, when an ultrasonic beam is radiated toward an obseation part, the ultrasonic beam generates a reflected echo by the tip cap 10 being a discontinuous face. With regard to a first reflected echo 13 therein, an output signal from the cap first echo detecting part 7 is inputted to a deciding circuit 8, and from a relation of irradiation power of the ultrasonic beam inputted already and amplitude of a first reflected echo, an irradiation level is decided and displayed. In such a way, whether the irradiation level of the ultrasonic beam radiated to the observation part, is proper or not can be confirmed by an operator, and a safe ultrasonic diagnosis can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic endoscope, and in particular, a probe having an ultrasonic transducer is inserted into a body cavity to obtain a tomographic image of the body cavity for ultrasonic diagnosis. It relates to an ultrasonic endoscope used for performing.

[0002]

2. Description of the Related Art In an ultrasonic endoscope, a tip cap is provided at the tip of an insertion portion to be inserted into a body cavity, and an ultrasonic transducer is provided inside the tip cap. The ultrasonic transducer is connected to a flexible shaft extending inside the insertion portion to the hand-held operation portion, and can be rotated by a rotation force applied to the flexible shaft. The ultrasonic transducer is driven according to the rotation angle of the ultrasonic transducer to irradiate the observation site with the ultrasonic beam, receive the reflected wave, and detect the received echo. The detected reception signal is subjected to signal processing and then displayed as an ultrasonic tomographic image on the monitor of the observation device to perform ultrasonic diagnosis.

[0003]

When performing ultrasonic diagnosis with such an ultrasonic endoscope, it is important to detect the irradiation level of the ultrasonic beam in order to ensure the safety of the observation site. If the irradiation level is regulated too much, sufficient image information may not be obtained. On the other hand, if the output is carelessly increased and irradiation is performed, a safety problem of the observation site may occur. Focusing on this point, Japanese Patent Laid-Open No. 142553/1990 discloses a device capable of giving an indication of the irradiation level and its distribution that are currently being implemented.

In the above-mentioned conventional example, the distribution of the estimated value of the irradiation level near the irradiation point can be notified to the operator in real time at the time of use, and the distribution of the estimated value of the irradiation level can be notified automatically. It was made possible.

Next, when performing ultrasonic diagnosis with an ultrasonic endoscope, if the ultrasonic transducer is deteriorated due to secular change or the like, the image quality and sensitivity of the ultrasonic tomographic image will be deteriorated. Therefore, there is a problem that proper ultrasonic diagnosis cannot be performed. Focusing on this point, in Japanese Utility Model Laid-Open No. 62-66608, the electrical characteristics of the phase and admittance of the ultrasonic transducer are directly determined to determine the superiority or inferiority of the ultrasonic transducer. The contents are disclosed.

In each of the ultrasonic endoscopes, the ultrasonic transducer is provided in the tip cap, so that when the irradiated ultrasonic beam is detected as the reception echo, the ultrasonic wave from the target observation site is detected. The reception eco from the tip cap is detected in addition to the reception eco. The unnecessary echo from the tip cap was not amplified with an appropriate gain, but was saturated and output by the preamplifier. The present invention has been proposed in view of the above-mentioned problems, and is provided with a means for amplifying a reception echo of a tip cap with an appropriate value, and an ultrasonic wave radiated from an ultrasonic transducer based on the reception echo. It is an object of the present invention to provide an ultrasonic endoscope provided with means for detecting the irradiation level of an acoustic wave beam and means for detecting the characteristics of an ultrasonic transducer.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention drives an ultrasonic transducer provided in a tip cap to irradiate an observation site with an ultrasonic beam to obtain an observation site. In an ultrasonic endoscope that obtains an ultrasonic tomographic image by receiving an echo signal from the tip end and performing signal processing, a means for detecting a first echo signal from the tip cap, and a means for detecting the first echo signal.
The ultrasonic endoscope is provided with a determining means for determining the irradiation amount of the ultrasonic beam based on the amplitude of the echo signal. An ultrasonic tomographic image is obtained by driving an ultrasonic transducer arranged in the tip cap to irradiate the observation site with an ultrasonic beam and receiving an echo signal from the observation site and performing signal processing. In the ultrasonic endoscope, the first from the tip cap is obtained.
The ultrasonic endoscope is provided with means for detecting the echo signal and determination means for determining the characteristics of the ultrasonic transducer by extracting the frequency characteristics from the first echo signal.

[0008]

With this configuration, the irradiation amount of the ultrasonic beam can be monitored in real time, and the operator can be provided with information regarding safety. Further, since information regarding deterioration and failure of the ultrasonic transducer can be given to the operator, correct ultrasonic diagnosis can be performed.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus according to a first embodiment of the present invention. The ultrasonic transducer 1 is connected to the transmission circuit 2 and driven. In addition, a preamplifier 3 is connected to the ultrasonic transducer 1 so that an echo from an observation site can be obtained.
The signal is amplified to a predetermined size.
A video processing unit 4 is connected to the preamplifier 3 so as to perform processing such as detection on an echo signal. A digital scan converter (DSC) 5 is connected to the video processing unit 4, converts an ultrasonic tomographic image obtained by scanning an observation site by an ultrasonic beam into a TV signal, and a display device 6
It is designed to supply a signal to.

Further, a cap first echo detecting section 7 is connected to the ultrasonic vibrator 1 so as to detect a first echo of the tip cap of the echo signal and perform a predetermined amplification. .. Further, a determination circuit 8 is connected to the cap first eco-detection unit 7 so as to determine a detection signal from the cap first eco-detection unit 7. The decision circuit 8 is connected to the DSC 5 and supplies decision information.

The ultrasonic transducer 1 is, as shown in FIG. 2A,
It is connected to a flexible shaft 9 extending from a hand-operated portion (not shown) so that it can rotate. These are disposed in the tip cap 10, the inside of the tip cap 10 is filled with the ultrasonic wave transmission medium 11, and the ultrasonic beam is irradiated to the target site through the ultrasonic wave transmission medium 11.

When the ultrasonic vibrator 1 is driven, the ultrasonic wave is emitted.
When the beam is irradiated toward the observation site, the ultrasonic beam first passes through the ultrasonic transmission medium 11 and produces a reflection echo at the tip cap 10 which is a discontinuous surface, which is received by the ultrasonic transducer 1. To be done. FIG. 2B shows such a state,
12 indicates the timing of transmission, and 13 and 14 indicate the first reflection echo from the tip cap 10 and the second reflection echo respectively.
It shows the reflection eco.

Of the above-mentioned reflection ecos, the first reflection eco-
It has been clarified from the design of the ultrasonic endoscope how the 13 is reflected. Therefore, if the gate circuit 16 (FIG. 3A) is provided in the first cap eco-detector 7 (FIG. 1) based on the timing and the peak voltage is detected, the irradiation level of the ultrasonic transducer 1 can be determined. Thus, it is possible to detect whether or not the ultrasonic beam is being emitted.

Therefore, as shown in FIG. 3A, the cap first
The eco-detection unit 7 is configured. This is the amplifier circuit 15,
3C has a sampling circuit 16 and a sample-hold circuit (S / H) 17, and the input signal shown in FIG. 3B is used as the output signal shown in FIG. 3C. Ultrasonic beam from the ultrasonic transducer 1
After the irradiation of the beam, the reception echo shown in FIG. 3B is received by the ultrasonic transducer 1. This reception eco is supplied to the cap first eco detector 7. Then, the amplification circuit 15 performs a predetermined amplification, and then the gate circuit causes the first reflection echo.
Gate processing is performed at the timing when 13 is received, and the peak value Vc is sampled and held by the S / H circuit 17.

The output signal from the first cap eco-detector 7 is input to the determination circuit 8. Here, the irradiation level is determined from the relationship between the irradiation power of the ultrasonic beam already input as data and the amplitude Vc of the first reflection echo. The determination result is input to the DSC 5 so as to be displayed on the display device 6 (FIG. 1). In this way, the operator can confirm whether or not the irradiation level of the ultrasonic beam irradiating the observation site is appropriate, and the safe ultrasonic diagnosis can be carried out.

FIG. 4 shows a second embodiment of the present invention, in which parts corresponding to those of the first embodiment are designated by the same reference numerals (the same applies to the following embodiments). In the first embodiment, a preamplifier 3 (FIG. 1) having an appropriate setting for the reception echo from the observation region is provided as the reception echo amplifier. On the other hand, in the present embodiment, the preamplifier 3 that can change the amplification degree is provided. For other configurations,
This is almost the same as in the first embodiment.

According to the present embodiment, with such a configuration, it is not necessary to provide the preamplifier for the echo received from the observation site and the amplifier for the cap first echo. Amplifying the reception eco from the observation site and the cap first eco while changing
Ultrasound diagnosis can be performed. Therefore, the device configuration can be simplified. The operation of determining the irradiation level from the relationship between the irradiation power of the ultrasonic beam and the amplitude Vc of the first reflection echo is the same as in the first embodiment.

Next, as a third embodiment of the present invention, an embodiment for detecting the characteristics of the ultrasonic transducer 1 will be described. Since the configuration of the apparatus is the same as that of the first and second embodiments, the description of the overlapping contents will be omitted. As shown in FIG. 5, the cap first eco changes due to changes in the characteristics of the ultrasonic transducer 1. FIG. 5A shows the case of a reception echo from a normal ultrasonic transducer, and FIG. 5B shows the reception echo when the frequency characteristic is deteriorated. In this case, the pulse width increases and the distance resolution decreases. Become. Figure 5C
Indicates the reception echo when the amplitude is deteriorated, which in this case causes a decrease in sensitivity.

In order to detect the characteristic change of the ultrasonic transducer 1, the frequency spectrum of the cap first echo is calculated by the judgment circuit 8 shown in FIGS. 1 and 4, and is received by the display unit 6 via the DSC 5. Display the eco signal waveform and spectrum. What is shown on the left side of FIGS. 5A, B, and C is a signal waveform, and what is shown on the right side is a spectrum. By seeing this display, the operator can check the characteristics of the ultrasonic transducer by seeing how it changes by comparing with the normal state of FIG. 5A.
Therefore, it is possible to obtain important information for performing proper ultrasonic diagnosis.

FIG. 6 shows another embodiment (fourth embodiment) of the method for detecting the characteristics of the ultrasonic transducer, which does not use the method for calculating the frequency spectrum of the first eco of the cap. This is a method of detecting the characteristics of the ultrasonic transducer. In the present embodiment, the amplitude detection circuit 1 is added to the determination circuit 8 (FIGS. 1 and 4).
8 and a pulse width detection circuit 19 are provided, and the output signals from these are input to the comparison circuit 20. So the cap first
The echo signal is envelope-detected, its peak amplitude and pulse width are detected, and the characteristics of the ultrasonic transducer are judged by comparison with the case of the normal first cap echo signal.

FIG. 7 shows each of the signals to be compared described above. FIG. 7A shows the received eco-signal,
FIG. 7B shows the waveform after envelope detection. To determine the characteristics of the ultrasonic transducer, the peak amplitude value Vp shown in FIG. 7C is detected from the envelope detection waveform of FIG. 7B, and the pulse width tw shown in FIG. 7D is further detected. .. Then, the characteristics of the ultrasonic transducer are determined by comparing each with the value in the normal case.

FIG. 8 shows a fifth embodiment of the present invention. In order to make more appropriate judgment when various judgments are made based on the cap first eco-signal in the above embodiments. It is an example of. When the irradiation level of the ultrasonic beam and the characteristics of the ultrasonic transducer are judged, the temperature of the ultrasonic transmission medium in the tip cap greatly affects the judgment contents. That is, the ultrasonic beam is attenuated when passing through the ultrasonic transmission medium, and the amount of this attenuation depends on the temperature of the ultrasonic transmission medium.

In the present embodiment, a constant temperature circulation device 21 is connected to the tip cap 10 so that the ultrasonic transmission medium circulates in the tip cap 10 while keeping the temperature constant. In this way, the attenuation amount of the ultrasonic beam is reduced, and the ultrasonic beam is irradiated to the observation site, so that effective ultrasonic diagnosis can be performed. The temperature control of the ultrasonic transmission medium can change the speed of sound of the ultrasonic beam propagating in the ultrasonic transmission medium. Therefore, while changing the focal length by controlling the refraction angle. Ultrasonic diagnosis can also be performed.

FIG. 9 shows a sixth embodiment of the present invention, in which the operator is provided with information concerning the rotation angle detection signal of the ultrasonic probe and the drive signal of the ultrasonic transducer to determine whether the apparatus is appropriate. It is designed to allow various operations. Ultrasonic Pro
A rotation angle detector 23 is provided in the rotary device 22 and a detection signal is detected by a first detector 24 connected to the rotation angle detector 23. Further, the detection operation can be confirmed by turning on or blinking the first indicator light 25 connected to the first detector 24.

The observation device 26 includes the first detector 24.
A second detector 27 connected to the second detector 27 is provided, which confirms whether or not the detection signal is transmitted to the observing device 26 side, and a second detector 27 connected to the second detector 27.
This can be confirmed by turning on or blinking the indicator light 28. The second detector 27 has a control unit 29.
Are connected, and the timing signal of the drive signal of the ultrasonic transducer 1 is generated based on the detection signal of the rotation angle.

Further, a third detector 30 is connected to the control unit 29, the timing signal of the drive signal is detected, and a third indicator lamp connected to the third detector 30. The detection operation can be confirmed by turning on or blinking 31. In addition, the third detector 3
A drive circuit 32 is connected to 0, and the control unit 29
A drive signal is supplied to the ultrasonic transducer 1 according to the timing signal output from the ultrasonic transducer 1. In this case, it can be confirmed by detecting whether or not the drive signal is actually output by the fourth detector 33 connected to the drive circuit 32 and turning on or blinking it by the fourth indicator light 34. It is like this.

Since the present embodiment is configured in this way, the operating condition of the device can be accurately displayed on the operator by the display means for displaying the exchange of signals on the probe side device 22 and the observation device 26 separately. It is possible to grasp the information and to operate the device properly. Although the display means is a display lamp in the embodiment, a required display means such as an LED may be used. Alternatively, it may be displayed on a monitor.

[0028]

As described above, according to the present invention, the irradiation level of the ultrasonic beam irradiating the observation site can be monitored in real time by detecting the first echo of the cap. -Provide safety information to the customer. Further, since information such as deterioration and failure of the ultrasonic transducer can be provided, the operator can properly operate the device while confirming such information and perform appropriate ultrasonic diagnosis.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of an ultrasonic beam irradiation state and a reception ecological state.

3 is an explanatory diagram of a cap first eco-detection unit in FIG. 1. FIG.

FIG. 4 is a schematic diagram of an apparatus according to a second embodiment of the present invention.

FIG. 5 shows a frequency spectrum according to a third embodiment of the present invention.

FIG. 6 is a partial schematic diagram of an apparatus according to a fourth embodiment of the present invention.

FIG. 7 is an explanatory diagram of a reception eco etc. according to the embodiment.

FIG. 8 is a partial schematic diagram of an apparatus according to a fifth embodiment of the present invention.

FIG. 9 is a schematic diagram of an apparatus according to a sixth embodiment of the present invention.

[Explanation of symbols]

 1 Ultrasonic Transducer 2 Transmitter 3 Preamplifier 4 Video Processor 5 DSC 6 Display 7 Cap First Eco-Detector 8 Judgment Circuit

Claims (2)

[Claims] 1. An ultrasonic transducer disposed in a tip cap is driven to irradiate an observation site with an ultrasonic beam, and an echo signal from the observation site is received to perform signal processing. In an ultrasonic endoscope for obtaining a sonic tomographic image, a means for detecting a first echo signal from the tip cap, and a determination for determining the irradiation amount of the ultrasonic beam based on the amplitude of the first echo signal An ultrasonic endoscope characterized in that it is provided with a means. 2. An ultrasonic transducer disposed in a tip cap is driven to irradiate an observation site with an ultrasonic beam, and an echo signal from the observation site is received to perform signal processing. In an ultrasonic endoscope for obtaining a sonic tomographic image, a means for detecting a first echo signal from the tip cap, and a characteristic of the ultrasonic transducer is determined by extracting a frequency characteristic from the first echo signal. An ultrasonic endoscope, comprising: