JP2001224594A - Ultrasonic endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively apply the method of imaging the elasticity information of an object to be measured and using it for diagnosis to an ultrasonic endoscope. SOLUTION: The ultrasonic endoscope 1 emits an ultrasonic wave by an ultrasonic transducer formed at the tip, receives the reflection signal from a living body, and applies a displacement to the biological tissue. An ultrasonic observation device 2 gains a hardness image by an operation using the reflection signal from the biological tissue which is displaced, and displays it on a monitor 5. Accordingly, the hardness of the biological tissue can be measured by use of the ultrasonic endoscope and used for diagnosis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic endoscope system capable of measuring the hardness of a living tissue and the like.

[0002]

2. Description of the Related Art Conventionally, ultrasonic pulses are repeatedly transmitted from an ultrasonic probe into a living body, and echoes of ultrasonic pulses reflected from the living body are received by the same or separately provided ultrasonic probes. By shifting the direction of transmitting and receiving the ultrasonic pulse little by little, there are various ultrasonic diagnostic apparatuses capable of displaying information collected from a plurality of directions in a living body as a visible ultrasonic diagnostic image. Proposed.

[0003] By using such an ultrasonic observation apparatus, it is possible to observe the movement and hardness of a tissue in a living body. This facilitates diagnosis of a lesion or the like.
A cross-correlation method is a method for relatively accurately detecting the movement of a tissue or the like. Further, there has been proposed a method in which the amount of calculation of the cross-correlation method is reduced to enable practical use.

Further, Japanese Patent Application Laid-Open No. H8-10260 discloses an ultrasonic diagnostic apparatus which detects displacement of a tissue in a living body, spatial inclination of the displacement, and obtains and displays the distribution of the displacement, velocity, distortion, and distortion velocity. Have been.

[0005]

However, in the proposal of Japanese Patent Application Laid-Open No. H8-10260, there is no description about an ultrasonic endoscope and no specific description for application to the ultrasonic endoscope. It cannot be fully utilized for sonic endoscopes. For example, in order to check the hardness or the like of a tissue, it is necessary to apply an action to a tissue in a living body and detect a displacement corresponding to the action. However, there is no description about generating a displacement. In addition, in order to simultaneously perform detection while generating displacement, it is important to set the timing of exerting the action and the acquisition timing of the detected displacement data, but this point is not mentioned. Also, in this proposal,
There is also a problem that the amount of calculation for obtaining the displacement and the like is extremely large and it takes a long time to obtain a result.

The present invention has been made in view of the above problems, and an ultrasonic endoscope system that can use an ultrasonic endoscope to image elasticity information of an object to be measured and use the image for diagnosis. The purpose is to provide.

Another object of the present invention is to provide an ultrasonic endoscope system capable of applying a displacement to a measurement object, imaging elasticity information of the measurement object and using the image for diagnosis. I do.

Another object of the present invention is to provide an ultrasonic endoscope system capable of absolutely evaluating displayed elasticity information.

[0009]

An ultrasonic endoscope system according to a first aspect of the present invention is provided with an ultrasonic transducer at a distal end of the endoscope, and transmits and receives ultrasonic signals from the ultrasonic transducer. In an ultrasonic endoscope system that generates an ultrasonic tomographic image of a measurement target, at least a part of an ultrasonic reflection signal of the measurement target for one screen is stored for at least two screens; The stored ultrasonic reflection signal is called, a displacement detecting means for calculating a displacement distribution of the measurement object between the screens with respect to the distal end portion of the ultrasonic endoscope by a calculation process, and a displacement rate distribution is calculated from a calculation result of the displacement detecting means. The present invention has a displacement rate detection means to be obtained, an imaging means for imaging the displacement rate distribution obtained by the displacement rate detection means, and a monitor for displaying an image generated by the imaging means. An ultrasonic endoscope system according to claim 2 is the ultrasonic endoscope system according to claim 1, further comprising a displacement generating means for applying a displacement to a measurement object, according to claim 3 of the present invention. Ultrasound endoscope system
The ultrasonic endoscope system according to claim 1, wherein the ultrasonic endoscope system receives an external force together with an object to be measured, is disposed in an ultrasonic observation region of the ultrasonic endoscope, and is formed of a known material. It further has a reference member.

In the first aspect of the present invention, the storage means comprises:
An ultrasonic reflection signal of the same region over two frames of the ultrasonic endoscope is stored. Using the displacement distribution detected by the displacement detecting means, the displacement rate detecting means detects a displacement rate in a local space. The imaging means causes the monitor to display an image of the distribution of the detected displacement rate.

According to a second aspect of the present invention, the displacement generating means positively applies displacement deformation to the observation target.

In a third aspect of the present invention, the reference member is
Subject to displacement / deformation simultaneously with the measurement object. The reference member is
It is made of a known material, and obtains an absolute displacement rate distribution of the living tissue using the displacement rate of the reference member.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 7 relate to a first embodiment of the present invention, FIG. 1 is a block diagram showing a system according to the first embodiment, and FIG. 2 is an internal block diagram of the ultrasonic observation apparatus 2 in FIG. FIG. 3 is an explanatory view showing a distal end portion of the ultrasonic endoscope 1, and FIG. 4 is a perspective view showing an appearance of the ultrasonic endoscope 1. FIG. 5 is a flowchart for explaining the operation, and FIG. 6 is “displacement / displacement rate calculation processing” in FIG.
FIG. 7 is an explanatory diagram for explaining data cut out for calculation processing.

In FIG. 4, the ultrasonic endoscope 1 has an elongated insertion section 51 which is elongated and can be inserted into a body cavity at a distal end side, and an operation section 52 formed at a hand side. ing. The endoscope image processor 7, the light source device 11, and the endoscope image processor 7 of FIG.
Ultrasonic observation device 2, suction pump 45 and water supply pump 27
Etc. are connected.

A distal end portion 54 is provided at the distal end of the insertion portion 51, and a bending portion 55 composed of a plurality of bending pieces is provided at the rear end. By operating the bending operation knob 56 provided on the operation section 52, the bending section 55 can be bent. As shown in FIG. 3, a balloon water supply / suction pipe 57 is provided in the distal end portion 54. The ultrasonic transducer 3 is disposed at an ultrasonic endoscope (EUS) distal end portion 58 at the distal end of the distal end portion 54, and the balloon 26 is attached around the transducer 3.

In the inspection using an ultrasonic endoscope, a deaerated water injection method or a balloon method is adopted in consideration of a large attenuation of ultrasonic waves in the air. The degassed water injection method is to perform an inspection with the degassed water injected into the lumen,
The balloon method uses a balloon 26 provided in an ultrasonic endoscope.
Inspection is performed by injecting degassed water into the container. In either method, the space between the lumen wall and the ultrasonic transmission unit is filled with degassed water to remove an air layer that causes ultrasonic attenuation. I have a picture.

The water supply pump 27 is connected to the balloon water supply suction line 5.
Water can be supplied to the balloon 26 through the airbag 7. In addition, the suction pump 45 can absorb water from the balloon 26 via the balloon water supply / suction line 57. The balloon 26 is inflated by being supplied with water, whereby
The living tissue is pressed to apply a displacement.

The ultrasonic endoscope 1 has a servo motor (not shown), and the ultrasonic transducer 3 is mechanically driven by the servo motor. Thereby, the ultrasonic endoscope 1 can obtain an ultrasonic image in the radial direction. Note that as the transducer, an electronic scan-type transducer or a transducer that performs a convex-type scan may be used.

The ultrasonic transducer 3 transmits and receives an ultrasonic signal to and from the ultrasonic observation device 2. The ultrasonic observation device 2 forms an ultrasonic image based on the received ultrasonic signal.

The ultrasonic endoscope 1 can acquire an optical image in addition to an ultrasonic image. The optical image is acquired by a CCD (not shown) provided at the distal end portion 6 of the ultrasonic endoscope, and a video signal based on the optical image is supplied to the endoscope image processor 7. The endoscope image processor generates an image based on the video signal,
To be transmitted.

As shown in FIG. 1, a man-machine interface such as an input unit 9 such as a keyboard and an input unit 8 such as a foot switch is connected to the ultrasonic observation apparatus 2.
These input units 8 and 9 transmit an operation signal based on a user operation of the operator to the control circuit 1 in the ultrasonic observation apparatus 2.
Output to 0. An arbitrary function can be assigned to the foot switch constituting the input unit 8. This function change is performed by changing the settings of the ultrasonic observation device 2. For example, the input unit 8 generates an operation signal indicating an instruction to start hardness measurement by operating a foot switch by a user.

The control circuit 10 controls the state of each unit in the ultrasonic observation apparatus 2 based on the input operation signal. Further, the control circuit 10 transmits an operation signal to the endoscope image processor 7 and the light source device 11. The endoscope image processor 7 and the light source device 11 are controlled based on operation signals. Note that the endoscope image processor 7 and the light source device 11 can also be controlled by a signal from another input unit (not shown).

The ultrasonic observation apparatus 2 generates an ultrasonic B-mode image based on a signal from the ultrasonic endoscope 1 by a known method, and generates a hardness image to be described later. The ultrasonic observation apparatus 2 selectively or simultaneously supplies the monitor 5 with the endoscope optical image, the hardness image, and the ultrasonic B-mode image from the endoscope image processor 7 to display them. Note that this display control is performed based on the input of the operator from the man-machine interface.

FIG. 2 shows an internal block of the ultrasonic observation apparatus 2.

The timing circuit 14 is controlled by the control circuit 10 to generate various timing signals.
For example, it outputs a sampling signal of the A / D converter 23 and a control signal synchronized with the sampling signal. Further, the timing circuit 14 outputs a position command signal to the servo circuit 12 and outputs a trigger signal to the pulsar circuit 16.

The servo circuit 12 is connected to an encoder (not shown) and a motor provided inside the ultrasonic endoscope 1. The servo circuit 12 constitutes a servo drive system that operates so that the displacement between the command position based on the position command signal from the timing circuit 14 and the current rotational position of the motor is set to zero.

The motor inside the ultrasonic endoscope 1 is connected to a power (rotational force) transmission mechanism including a flexible shaft 15 for transmitting a rotational force. The rotational force transmission mechanism is connected to the ultrasonic transducer 3 disposed at the distal end of the ultrasonic endoscope in the ultrasonic endoscope 1 and drives the ultrasonic transducer 3 to rotate.

The pulsar circuit 16 is electrically connected to the ultrasonic transducer 3, and is connected to the timing circuit 1.
The pulse signal for generating the ultrasonic signal is supplied to the ultrasonic transducer 3 when a trigger signal generated by the ultrasonic signal 4 is given.

The ultrasonic transducer 3 generates an ultrasonic wave based on the input pulse signal and transmits the generated ultrasonic wave toward the object to be measured. Also, the ultrasonic transducer 3
Receives a reflected signal of the transmitted ultrasonic wave from the object to be measured. The ultrasonic transducer 3 outputs the received reflected signal to the amplifier circuit (AMP) 17 of the ultrasonic observation device 2.

The amplifier circuit 17 converts the input reflected signal into a signal intensity suitable for the subsequent processing and outputs the signal to an envelope circuit (BPF) 18. Envelope circuit 18
Detects the envelope of the input reflected signal and
Output to a D converter (A / D) 19. The A / D converter 19 converts the envelope of the input reflection signal into a digital signal and outputs the digital signal to the memory 20 and the imaging circuit 21. The memory 20 stores the input digital signal.

The signal stored in the memory 20 is calculated by the calculation unit 2
5 is supplied to the imaging circuit 21. Imaging circuit 2
1 generates an ultrasonic B-mode image based on the input data.

On the other hand, the reflected signal amplified by the amplifier circuit 17 is also supplied to the band pass filter 22.
The band-pass filter 22 removes (attenuates) low-frequency components and high-frequency components unnecessary for data processing, which will be described later.
/ D converter 23. A / D converter 23
Converts the input signal from the bandpass filter 22 into a digital signal and outputs the digital signal to the memory 24. The memory 24 stores the input signal. Here, the signal stored in the memory 24 is an AC signal (rf signal) having the frequency band of the ultrasonic reflection signal. The bandpass filter 22 has a characteristic of transmitting the ultrasonic reflection signal in the frequency band.

The calculation unit 25 generates a hardness image for displaying the hardness of the living tissue based on the data stored in the memories 20 and 24 and outputs the hardness image to the imaging circuit 21.
The imaging circuit 21 is also provided with an endoscope optical image from the endoscope image processor 7 and outputs an ultrasonic B-mode image, a hardness image, and an endoscope optical image to the monitor 5 as appropriate.
Note that the calculation unit 25 includes a digital signal processor (D
SP) or the like.

Next, the operation of the embodiment constructed as described above will be described with reference to the flowcharts of FIGS.
This will be described with reference to the explanatory diagram of FIG. In FIG. 5, the flow is divided into steps S3 and S4 and step S5.
, S6 progress in parallel.

For example, an operation when the present invention is applied to observation of the esophagus will be described.

First, the operator attaches an ultrasonic observation-like balloon 26 to the end of the ultrasonic endoscope. Next, the ultrasonic endoscope 1 is inserted into the esophagus by a normal method, and observation of the esophageal tissue by the ultrasonic endoscope 1 is performed by a balloon method.

Here, it is assumed that the operator acquires hardness information within the observation visual field. In this case, the operator holds the ultrasonic endoscope 1 in a state where a part where hardness information is desired is located in the observation visual field. Next, the operator presses the foot switch of the input unit 8 to start measurement for hardness measurement (step S1 in FIG. 5).

Since the foot switch is assigned to the hardness measurement start switch, the hardness measurement can be started without moving the hand holding the ultrasonic endoscope 1 and one person can perform the measurement. Even when the operator operates, it is possible to suppress the blur of the ultrasonic endoscope distal end portion 58 and improve the accuracy of hardness measurement.

The switch for starting the hardness measurement is not limited to the foot switch, but may be a hand switch, a voice recognition device, a line-of-sight recognition device, or the like separate from the ultrasonic endoscope 1. Similar effects can be expected. Further, as a switch for instructing the start of the hardness measurement, a switch (not shown) provided on the ultrasonic observation device 2, a keyboard, a switch provided on the main body of the ultrasonic endoscope 1, or the like can be substituted.

An operation signal based on the operation of the input section 8 (foot switch) is given to the control circuit 10. The control circuit 10 transmits a signal to each unit for measuring hardness and starting a required operation based on a program.

The water pump 27 is connected to the control circuit 10.
The operation is started by the signal from the control unit and the water supply to the balloon 26 is started (step S2). The balloon 26 is inflated by supplying water through the balloon water supply / suction line 57. Then, the living tissue (the esophageal wall) is compressed by the balloon 26 and is displaced.

The ultrasonic transducer 3 transmits and receives an ultrasonic wave and supplies a reflected signal from a living tissue to the amplifier circuit 17. The amplifier circuit 17 amplifies the reflected signal and supplies it to the envelope circuit 18 and the band pass filter 22. The reflected signal is enveloped by an envelope circuit 18 and supplied to an A / D converter 19. The reflected signal is band-limited by the band-pass filter 22 and then supplied to the A / D converter 23. A / D converters 19 and 23 encode the input signals.

When the water supply to the balloon 26 is started, A
A predetermined amount of data (data of two or more frames in a specific area) encoded by the / D converter 19 and the A / D converter 23 is recorded in the memories 20 and 24, respectively (steps S3 and S5). Data for generating a B-mode image is recorded in the memory 20, and data for obtaining a displacement / displacement ratio distribution is recorded in the memory 24. When a predetermined amount of data is recorded in the memories 20 and 24, the control circuit 10 sends a signal for stopping water supply to the balloon 26 to the water supply pump 27, and stops water supply (step S6).

On the other hand, in step S4, the calculation unit 25 calculates the displacement / displacement ratio distribution between frames based on the data stored in the memory 24, and calculates a numerical value used for the hardness image.

During the recording in the memories 20 and 24 and the calculation by the calculation unit 25, the current ultrasonic observation image from the ultrasonic endoscope 1 is transmitted from the A / D converter 19 via the path A. It is supplied to the imaging circuit 21. Thereby, the data of the observation image generated by the imaging circuit 21 can be supplied to the monitor 5, and the current ultrasonic observation image can be displayed on the monitor 5.

FIG. 6 shows the "displacement / displacement rate calculation process" in FIG.
5 is a flowchart showing an internal flow of the embodiment. FIG. 7 shows an image of data cut out by calculation. With reference to FIGS. 6 and 7, a program for detecting the displacement and the displacement rate distribution of the measurement target will be described.

The calculation method of FIG.
It is an improvement over the method disclosed in Japanese Patent Application Laid-Open Publication No. H10-15064 in that the calculation amount is significantly reduced by limiting the band of the cross spectrum calculation.

That is, in step S11 of FIG. 6, first, data of the first frame is cut out, and then data of the second frame is cut out (step S12). Here, the data of the first frame refers to a data set acquired from a frame used as a reference in the present calculation, and the second frame is referred to as a data set measured at a timing different from that of the first frame. This means a data set in the same area as one frame.

The data of the extracted first and second frames is stored in the memory 24. An arc-shaped region R in FIG. 7 indicates a region that has been cut out and stored in the memory 24.
Among the data of the first frame stored in the memory 24, the data of the region Rmn (the shaded portion in FIG. 7) used for the calculation is called. The data in the region Rk is defined as data M1mn. The data to be called is matrix data, and has a shape shown in FIG. 7 in the real space. Here, the subscripts m and n indicate the positions to be cut out, and n is incremented by shifting the region in the traveling direction of the ultrasonic wave. M is incremented by shifting the area in the direction in which the ultrasonic transducer is scanned. The maximum values of m and n are M and N, respectively.

Next, similarly, in the data of the second frame stored in the memory 24, the region Rm used for calculation is used.
Call the data of n. The data of the second frame of the called region Rk is defined as data M2mn. Data M1m
n and data M2mn are subjected to two-dimensional Fourier transform (steps S13 and S15), and the respective results are
F1mn and F2mn. Next, F1mn, F2m
The cross spectrum of n is calculated (step S17). This cross spectrum calculation result is defined as Cmn.

In this embodiment, prior to the cross spectrum calculation processing, in steps S14 and S16,
The data used for calculation is restricted.

That is, since the calculation results F1mn and F2mn are obtained by Fourier-transforming the ultrasonic signal, the intensity of the center frequency of the ultrasonic transducer 3 is high, and the intensity of the other frequencies is low. Therefore, in the present embodiment, in the cross spectrum calculation, only the elements near the center frequency of the ultrasonic transducer 3 are calculated, and in the subsequent calculation processing, only the elements used in the cross spectrum calculation are performed. As a result, the amount of calculation can be significantly reduced.

As for the displacement of the ultrasonic transducer 3 in the rotation direction (scan direction), the data acquisition interval is slow. Also, the expected displacement is expected to be small with respect to the scan interval. Therefore, only low-frequency components need to be extracted as data used for displacement calculation.

The selection of data used for displacement calculation is not limited to the above method. This can also be realized by adding the following operation after step S17. The element of the maximum intensity is extracted from the cross spectrum calculation result. The elements of the cross spectrum are compared with the maximum intensity of the cross spectrum, and only the elements that are larger than a certain ratio are used in subsequent calculations.
For example, assuming that the maximum intensity of -9 dB is a shresh hold value, about 20% of the number of elements is selected and used for calculation.
Further, for example, when -3 dB is set as the shresh hold value, 5% of the number of elements is selected and used for the calculation. Thereby, the amount of calculation can be reduced. For example, -3d
The ratio of calculation accuracy / calculation amount when B is a shresh hold indicates that this method is highly effective.

As described above, according to this method, the amount of calculation can be significantly reduced without substantially reducing the calculation accuracy. In addition, this method can also cope with a case where the frequency band changes such that the high-frequency component is attenuated and the center frequency shifts to the low-frequency side while the ultrasonic signal is transmitted through the measurement object.

Further, even when ultrasonic transducers having different center frequencies are used, it is possible to cope without using separate filters. Furthermore, even in the case of adopting a method of converging the displacement calculation by repeatedly calculating, by performing the calculation only with the high-intensity signal component,
It is possible to expand the conditions under which the displacement calculation can be completed at once without significantly lowering the accuracy of the displacement calculation result. This also makes it possible to greatly reduce the amount of calculation. This method can be used together with steps S14 and S16, or can be omitted.

Next, Cmn obtained in step S18
Is used to find a cost function derived by the weighted least squares method, and a value that minimizes this cost function is found.
The obtained value indicates the local displacement of the target area during the observation period of the first and second frames. This method is based on IEICE TR
ANS.FUNDAMENTALS.VOL.E78-A No.12 December 1995p16
55-p1664 `` Phantom Experiment on Estimation of Sh
ear Modulus Distribution in Soft Tissue from Ultra
sonic Measurement of Displacement VectorField '' C.
See Sumi A. Suzuki K. Nakayama for details.

Next, an integrated displacement is obtained by integrating the local displacements (step S19). In step S20,
It is determined whether the displacement calculation has been completed. If the processing has not been completed, the cutout position of the image to be subjected to the next displacement calculation is calculated in step S21, and the process returns to step S11.

The living tissue (esophageal wall) to be measured is
It is a viscoelastic body and a continuum. Therefore, an object existing in a close space before applying the displacement will exist in a close space even after applying the displacement. Therefore, in step S21, the data of the area to be called from the second frame is shifted by the amount of the displacement calculation obtained earlier when performing the next displacement calculation. Thereby, it is possible to predict that the displacement amount calculated in the next displacement calculation is minute.

Thereafter, steps S11 to S21 are repeated to obtain a displacement calculation distribution. The displacement rate can be obtained from the spatial inclination of the displacement calculation distribution. When the displacement calculation is completed, the process proceeds from step S20 to step S22, and the first derivative of the displacement in the beam direction is obtained. This calculation result indicates the hardness of the living tissue.

The imaging circuit 21 generates a hardness image indicating a hardness distribution based on the output of the calculation unit 25. The imaging circuit 21 generates a hardness image and an ultrasonic endoscopic tomographic image at the time of observing the hardness image, and displays these images in parallel or superimposes a video signal on the monitor 5. Output to Note that the imaging circuit 21 can also display the ultrasonic endoscope optical image on the monitor 5 selectively or together with the hardness image and the ultrasonic endoscope tomographic image in various display forms. .

As described above, in the present embodiment, it is possible to apply a displacement to the object to be measured, to image elasticity information of the object to be used for diagnosis, and to acquire elasticity information. Can be significantly reduced.

The present embodiment can be used at various sites in a living body.

For example, a case where the stomach is observed will be described.

Since the stomach has a wide lumen unlike the esophagus, the balloon cannot hold the tissue. For this reason, even in general ultrasonic endoscopic observation, observation using a balloon is rarely performed, and an ultrasonic transmitting substance such as degassed water is directly injected into the stomach and injected into the substance. A technique of observing an ultrasonic endoscope has been adopted.

Also in the present embodiment, the observation of the hardness of the stomach is performed by the ultrasonic endoscope observation by the immersion method.
That is, when starting the hardness measurement, the operator instructs to start the hardness measurement by pressing the input unit 8 such as a foot switch.

Thus, water supply is started by the water supply pump 27 in the same manner as when observing the esophagus. The supplied water is released directly into the stomach, increasing the amount of water inside the stomach. As a result, the stomach tissue is compressed due to an increase in the compressive force of the water. Using this compression, hardness measurement is performed in the same manner as described above.

FIGS. 8 and 9 are explanatory views showing a distal end portion of a balloon ultrasonic endoscope employed in the second embodiment of the present invention, and FIG. 9 is a flowchart showing an operation flow of the embodiment. 8, the same components as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted.

In the first embodiment, since there is no means for estimating the external force applied to the tissue, the absolute hardness of the tissue cannot be obtained only by the obtained compressibility of the living body. This embodiment makes it possible to obtain the absolute hardness of the tissue.

In this embodiment, as shown in FIG. 8, a reference hardness member 62 is attached to a distal end portion 61 of a balloon ultrasonic endoscope.

The reference hardness member 62 is a member having a known hardness that is close to the hardness of the object to be measured (for example, a gastrointestinal tract organ). For example, as the reference hardness member 62, a silicone resin material such as silicone gel or silicone rubber, a natural rubber material, a synthetic rubber material, agar, or the like is employed. The reference hardness member 62 preferably generates a reflected signal having a sound speed relatively close to the sound speed of the reflected signal of the measurement object with respect to the sound speed of the ultrasonic wave.

It is preferable that the balloon 26 and the reference hardness member 62 are joined by an adhesive having excellent flexibility such as a silicone adhesive. Various joining methods can be selected according to the materials of the balloon 26 and the reference hardness member 62.

In the present embodiment, other components such as the ultrasonic observation device 2 are the same as those of the first embodiment.

Next, the operation of the second embodiment configured as described above will be described. The flowchart of FIG. 9 is different from the flowchart of FIG. 6 in steps S23 and S24.
Is added.

The operator performs observation by inserting the distal end portion 61 of the ultrasonic endoscope into the body. Now, the reference hardness member 62 is
It is assumed that it is located within the ultrasonic observation field of view of the ultrasonic endoscope. In this state, when the operator presses the input unit 8 such as a foot switch, the hardness measurement is started.

The hardness measurement is performed in the same manner as in the first embodiment. In the present embodiment, the reference hardness member 62
Undergoes expansion and contraction integrally with the living tissue. The displacement / deformation state of the reference hardness member 62 is also stored as data.

Next, a method for detecting the amount of displacement of the reference hardness member 62 will be described.

The ultrasonic waves emitted from the ultrasonic transducer 3 are reflected at the joint surface between the reference hardness member 62 and the balloon 26 and also at the contact surface between the reference hardness member 62 and the living body. . That is, the ultrasonic observation apparatus 2 can ultrasonically observe a clear strong reflected signal on both the joint surface of the reference hardness member 62 with the balloon 26 and the contact surface with the living body. Then, the displacement can be clarified by detecting a change in the time difference between these two reflected signals.

An example of a method for obtaining the displacement amount of the reference hardness member 62 will be described.

The ultrasonic waves from the ultrasonic transducer 3 are hardly reflected by the water inside the balloon 26, and the amplitude of the signal reflected by the water is extremely small. On the other hand, the ultrasonic wave from the ultrasonic transducer 3 is reflected at the interface of the balloon 26 (= the interface of the reference hardness member 62), and a reflected signal having a large amplitude returns to the ultrasonic transducer 3. Further, the calculation unit 25 of the ultrasonic observation apparatus 2 in which the reflection signal from the interface between the reference hardness member 62 and the living tissue is also observed with sufficient amplitude, uses the data stored in the memory 24 to calculate the first reflection signal. Search for peak position (time). The reference hardness member 62 has a known material and a known dimension, and expansion and contraction of the reference hardness member 62 is weak.

Accordingly, the time difference between the time at which the peak position of the first reflected signal is obtained and the time at which the reflected signal from the interface between the reference hardness member 62 and the living tissue is observed can be roughly estimated. The calculation unit 25 detects a peak position (time) near the estimated time. The calculation unit 25 calculates the current thickness of the reference hardness member 62 based on the time difference between the detected peak positions.

The calculation unit 25 calculates the thickness in the second frame following the first frame. And the first,
The compression ratio between the frames of the reference hardness member 62 is determined by comparing the calculation results in the second frame.

Next, the calculation unit 25 obtains the compression ratio between frames of the living tissue by the same method as in the first embodiment. As described above, the absolute hardness of the living tissue cannot be obtained only by the compression ratio between the frames of the living tissue. Therefore, in the present embodiment, the result (compression amount) of the primary differentiation of the reference hardness member is extracted in step S23, and is normalized by the compression ratio of the reference hardness member 62 in step S24.

The reference hardness member 62 has a known elastic modulus. Therefore, it is possible to convert the normalized compression ratio into an elastic modulus. The calculation unit 25 converts the compressibility of the tissue normalized by the compressibility of the reference hardness member 62 into an elastic modulus using a known elastic modulus of the reference hardness member 62.

Now, it is assumed that the elastic modulus of the reference hardness member 62 is a known value k. The thickness and the compression amount Δd of the reference hardness member 62 are measured by the ultrasonic signal as described above. As described above, the spatial distribution Δd (m, n) (m, n indicates the position of the space) of the compression amount of the living tissue that is the measurement target is measured by the same method as in the first embodiment. Is done.

Here, assuming that the elastic modulus of the tissue at the position (m, n) is kmn, the following relationship holds: k: kmnmnΔ: Δd (m, n) Higher).

Thus, the elastic modulus at (m, n) is given by a normalization process (step S24) shown by the following equation.

Kmn = kΔd (m, n) / Δd Thus, the calculation unit 25 obtains the hardness (elastic modulus) of the living tissue as an absolute numerical value. The imaging circuit 21 displays on the monitor 5 the absolute hardness of the living tissue calculated by the calculation unit 25.

As described above, the present embodiment has an advantage that elasticity information of a living tissue can be absolutely evaluated.

The method for calculating the compression ratio of the reference hardness member 62 is not limited to the above method, and any method such as the displacement calculation method used in the first embodiment may be used. Good.

FIGS. 10 and 11 are flow charts for explaining the displacement calculation employed in the third embodiment of the present invention. The configuration in the present embodiment is the same as that in the first embodiment. The present embodiment corresponds to a case where the ultrasonic transducer 3 does not rotate regularly according to the rotation of the motor. In FIG. 10, the same steps as those in FIG. 5 are denoted by the same reference numerals, and description thereof will be omitted.

The operation unit 52 of the ultrasonic endoscope 1 shown in FIG. 4 includes a motor and an encoder (not shown).

The rotation shaft of the motor is connected to a power transmission mechanism (see FIG. 3) such as a flexible shaft 15 provided inside the endoscope 1.

[0094] The flexible shaft 15 constituting the power transmission mechanism is connected to the ultrasonic transducer 3 provided at the distal end portion 58 of the ultrasonic endoscope. The ultrasonic transducer 3 is rotationally driven by the rotation of the motor being transmitted by the flexible shaft 15.

However, since the flexible shaft 15 constituting the power transmission mechanism is inserted through the inside of the ultrasonic endoscope 1 main body and has a portion that flexibly bends, the power transmission is not uniform. May occur.

For this reason, the ultrasonic transducer 3 may make a motion different from the motion corresponding to the rotation of the motor, and there is a disadvantage that the observation position may be shifted.

Then, the ultrasonic signal reflected from the living body is also affected by the motion of the ultrasonic transducer 3,
When the displacement calculation shown in the first embodiment is performed,
Correct displacement calculation results cannot be obtained. Further, there is a possibility that an error such as an inability to calculate the displacement occurs.

Further, a similar phenomenon may occur when the main body of the ultrasonic endoscope 1 is twisted. For these reasons, it is possible that a hardness image cannot be displayed.

Therefore, in the present embodiment, the operation flow shown in FIGS. 10 and 11 is adopted.

The method of acquiring the reflected signal of the ultrasonic wave is the same as in the first or second embodiment. The data is stored in steps S3 and S5, and when the data storage is completed in step S34, the water supply to the balloon is stopped in step S35.

In step S31, a rotation unevenness detection program is executed. FIG. 11 shows the flow of the rotation unevenness detection program of FIG. Rotation unevenness (rotational deviation) is detected based on a correlation function result in each area within a predetermined range.

That is, in step S41, the variable n is set to -N
Is calculated, the calculation unit 25 determines in step S42 that one Amo in the first frame stored in the memory 20
Call the de signal. Next, the calculation unit 25 calculates the Amod of the called first frame among the data of the second frame.
An Amode signal that is shifted from the e signal by n lines in measurement timing is extracted.

Next, in step S44, a correlation coefficient between the two Amode signals of the first and second frames is obtained. Here, the position of the data for which the correlation calculation is performed is slightly shifted, and the calculation is repeatedly performed.
It is preferable to search for a position where the correlation coefficient is maximum between the signals, and use that value as the correlation coefficient. Further, the calculation is not performed for all the data areas, and a specific section is selected from the Amode signal to perform the main calculation, thereby reducing the calculation amount. In addition, the calculation accuracy can be improved by setting a plurality of the above specific sections and taking an average.

The calculation unit 25 stores the correlation calculation result as C (n) (step S45), and shifts the position of the Amode signal in the second frame for calculating the correlation by incrementing n. If n has not reached the last window position N, the process returns to step S43, and the correlation function calculation is repeated. When the calculation of the correlation coefficient is completed in all the sections, in the next step S48, the maximum value of the correlation coefficient is obtained.

The value of n at this time is stored as the amount of rotational displacement of the transducer (steps S49, S32). Further, by repeating the above operation (steps S41 to S49) for a plurality of Amode signals of the first frame, finer rotation unevenness of the transducer can be detected.

Next, in step S33, when calling the signal of the area used for calculation from the signal of the second frame,
Shift the space that is determined by the correction amount. And the first and second
The displacement is calculated in the same manner as in the embodiment (step S4).
).

In this way, it is possible to calculate the displacement in consideration of the rotational deviation of the ultrasonic transducer 3 and the torsion of the ultrasonic endoscope tip 6.

As described above, in this embodiment, the displacement calculation result can be improved.

FIG. 12 is an explanatory diagram showing an ultrasonic endoscope distal end portion 71 employed in the fourth embodiment of the present invention. This embodiment makes it possible to obtain the absolute hardness of the tissue even when the reference hardness member is omitted.

In this embodiment, the balloon 72 attached to the distal end portion 71 of the ultrasonic endoscope is formed such that the portion through which the ultrasonic signal is transmitted when the balloon is injected with water is thick. The thickness of this portion is desirably three or more wavelengths with respect to the wavelength of the ultrasonic signal. Thereby, the balloon 72 itself functions as a reference hardness member.

The other structure and operation are the same as in the second embodiment.

As described above, in this embodiment, the absolute hardness can be measured even if the reference hardness member is omitted.

FIG. 13 is an explanatory view showing a distal end portion of an ultrasonic endoscope employed in the fifth embodiment of the present invention.
This embodiment makes it possible to obtain the absolute hardness of the tissue using a normal balloon.

As shown in FIG. 13, a forceps hole 75 is provided at the distal end of the ultrasonic endoscope, and a catheter 76 is inserted into the forceps hole 75. A reference hardness member 79 is attached to the distal end of the catheter 76.

A hood 7 is provided on the distal end side of the catheter 76.
8 is also attached. The hood 78 is advanced and retracted by operating an operation unit (not shown) on the catheter hand side, and is in a state of covering the reference hardness member 79 or the reference hardness member 79.
Is exposed.

The hood 78 covers the reference hardness member 79 when the catheter 76 is inserted into the distal end portion of the ultrasonic endoscope through the forceps hole 75, and protects the soft reference hardness member 79.

Next, the operation of the embodiment configured as described above will be described.

During the execution of the ultrasonic endoscopy by the general balloon method, the hardness of the living tissue is measured. In this case, first, the catheter 7 is inserted into the forceps hole 75.
Insert 6. The hood 78 is advanced to the distal end side of the catheter 76 so as to cover the reference hardness member 79. Next, the distal end of the catheter 76 is introduced into the observation field of the ultrasonic endoscope by operating the forceps raising device 77 provided at the distal end of the ultrasonic endoscope.

Here, the hood 78 is retracted to expose the reference hardness member 79. Thereby, the reference hardness member 79
Can be captured in the observation field of view of the ultrasonic endoscope.

The subsequent operation is the same as in the second embodiment.

As described above, in the present embodiment, it is possible to measure the absolute hardness of the living tissue while wearing a normal balloon.

FIG. 14 is an explanatory diagram showing a distal end portion of an ultrasonic endoscope employed in the sixth embodiment of the present invention.
This embodiment also makes it possible to obtain the absolute hardness of the living tissue.

At the distal end of the ultrasonic endoscope, there is provided a mounting member 90 constituted by using a reference hardness member. The mounting member 90 is formed in a donut shape, and is provided with a pair of protrusions 92 on the inner peripheral front and rear ends. On the other hand, a pair of grooves 91 is formed at a position where the front end and the rear end of the mounting member 90 are attached to the distal end portion of the ultrasonic endoscope,
By fitting the projection 92 into the groove 91, the mounting member 90 is prevented from falling off.

The other structure is the same as that of the second embodiment.

Next, the operation of the embodiment configured as described above will be described.

In the state shown in FIG. 14, observation is performed by inserting an ultrasonic endoscope into the body cavity. In this state, a displacement is applied to the living tissue by directly pressing the ultrasonic endoscope against the living tissue.

The other operations are the same as in the second embodiment. As described above, also in the present embodiment, the absolute hardness of the living tissue can be measured.

FIG. 15 is an explanatory view showing a tip portion of an ultrasonic endoscope employed in the seventh embodiment of the present invention.
This embodiment is applied to a submersion method.

A forceps hole 98 is provided in the ultrasonic endoscope.
A catheter 95 is inserted through the forceps hole 98. A balloon 96 is attached to the distal end of the catheter 95. A pipe (not shown) is provided inside the catheter 95. Water is supplied to the inside of the balloon 96 via the pipe, and water in the balloon 96 can be absorbed.

The other structure is the same as that of the first embodiment.

Next, the operation of the thus configured embodiment will be described.

In the present embodiment, an ultrasonic endoscopy is performed by the immersion method. When measuring the hardness of the living tissue, the catheter 95 is inserted through the forceps hole 98 of the ultrasonic endoscope to the ultrasonic endoscope distal end portion 94 side.

Next, water is supplied into the balloon 96 to inflate the balloon, and the balloon 96 is pressed against the living tissue 97 to apply a displacement to the living tissue 97. In this state, data is obtained by emitting ultrasonic waves.

The other operations are the same as in the first embodiment.

Thus, hardness measurement is possible in this embodiment as well.

The reason why the living tissue 97 is pressed by the balloon 96 is to increase the area of the pressed portion of the living tissue 97. As a result, the area pressed uniformly increases, so that the hardness can be measured in a wide range of tissues. Conversely, when the target region to be measured is small, the tissue may be directly pushed by the tip of the catheter without inflating the balloon 96.

In this case, general endoscope forceps such as grasping forceps can be used.

FIG. 16 is an explanatory view showing a distal end portion of an ultrasonic endoscope employed in the eighth embodiment of the present invention.
This embodiment employs a balloon that expands in the direction of the ultrasonic observation field of view.

In the present embodiment, a forward-looking type ultrasonic endoscope apparatus in which the ultrasonic observation field of view is forward is employed. In FIG. 16, a balloon 101 attached to the ultrasonic endoscope distal end portion 100 is configured to expand in the ultrasonic observation visual field direction.

Otherwise, the configuration is the same as that of the first embodiment.

In this embodiment, the hardness of the living tissue can be measured by the same method as in the first embodiment.

Further, in the present embodiment, there is an advantage that the displacement is easily applied since the endoscope is displaced in the reciprocating direction. Further, it is possible to prevent the ultrasonic endoscope from accidentally moving. Thereby, there is also an advantage that measurement becomes easy.

If the hardness reference member is mounted on the balloon, the same effect as in the second embodiment can be obtained.

FIG. 17 is a flowchart for explaining the displacement calculation employed in the ninth embodiment of the present invention. The configuration of the present embodiment is the same as that of the first embodiment, and the only difference is that the calculation method of the calculation unit 25 is different from that of the first embodiment.

The displacement calculation according to the operation flow of the first embodiment shown in FIG. 6 employs a tracking algorithm. Therefore, a large displacement is not calculated by one displacement calculation.

However, in such a displacement calculation, if the noise at the time of measurement increases as compared with the signal, the calculation result may become a value significantly larger than the original value. Then, the calculation result will affect the next calculation,
It is also conceivable that the displacement calculation result becomes inaccurate.

Therefore, in the present embodiment, when a displacement calculation result having a large value is generated, the result is reduced and evaluated to reduce an error in the displacement calculation result.

In order to realize this function, in the present embodiment, the calculating section 25 is provided with a correction means for limiting the displacement result when the displacement amount becomes large.

This correcting means can be realized by the following function.

Now, assuming that the displacement calculation result before correction is x and the displacement calculation result after correction is X, Function form that satisfies the condition

The following format is given as an example of this function.

[0152] The processing in steps S51 to S54 in FIG.
1 to S3, S5 and S6. The processing in step S55 in FIG. 17 is the same as the processing in steps S11 to S19 in FIG.

In the present embodiment, the following step S
In 56, the calculation unit 25 performs displacement correction using the function described above. Subsequent processing includes steps S20 to S22 in FIG.
Is the same as the processing of

As described above, by introducing the above-described displacement correction function, a numerical value which is an accurate calculation result is hardly corrected, and an abnormal calculation result (large displacement calculation result) is corrected to a predetermined value A.

As described above, in the present embodiment, even if an abnormal value occurs in the calculation result, the influence on the subsequent calculation can be reduced, and the accuracy of the displacement calculation result can be improved.

FIG. 18 is a flowchart showing an operation flow employed in the tenth embodiment of the present invention. In FIG. 18, the same steps as those in FIG. The configuration in the present embodiment is the first
This is the same as the embodiment.

In the present embodiment, after displaying the image showing the hardness and elasticity information of the living tissue in step S66, if the measurement is not completed, the process proceeds to step S67.
Then, the process returns to steps S63 and S69, the ultrasonic signals are acquired again in the memory 20 and the memory 24, and the previously used data and the displacement / displacement ratio distribution calculation are performed.

Thus, an image showing the hardness and elasticity information of the living tissue can be displayed continuously. When the measurement is completed, the water supply to the balloon is stopped in step S70.

FIG. 19 is a flowchart showing an operation flow employed in the eleventh embodiment of the present invention. The configuration in the present embodiment is the same as that in the first embodiment. In the present embodiment, hardness / elasticity information is continuously displayed as an image.

When an image display of the hardness and elasticity information of the living tissue is instructed, water supply to the balloon is started (step S7).
1) Data is acquired from the memories 20 and 24 based on the reflection signal of the ultrasonic signal (steps S81 and S83). The acquisition of the reflected signal is repeated until the measurement completion is instructed (the loop of steps S82 and S81 and the steps S84 and S84).
83 loops). The measurement may be stopped when the data to be stored exceeds the capacity of the memory 20 or 24. If it is determined that the measurement is completed, step S
At 85, the water supply to the balloon is stopped, and the measurement is terminated (step S86).

On the other hand, after initializing the variable n (step S72), the calculation unit 25 calls the data held in the memory 20 (step S73), and then increments the variable n (step S74), and If a frame exists, the data of this n frame is called (step S75,
S76). Then, the calculation unit 25 performs a displacement / displacement rate distribution calculation for the continuous frames (step S77).
The imaging circuit 21 continuously displays an image indicating the hardness and elasticity information of the living tissue on the monitor 5 according to the output of the calculation unit 25 (step S78).

As described above, in the present embodiment, an image relating to hardness / elasticity information of a living tissue can be displayed continuously.

In the present embodiment, even when the calculation speed is lower than the data acquisition speed, continuous displacement calculation is performed, and the hardness / elasticity information of the living tissue is continuously displayed as an image. be able to.

FIG. 20 is a flowchart showing an operation flow employed in the twelfth embodiment of the present invention. The configuration in the present embodiment is the same as that in the first embodiment. This embodiment shows a flow in "calculation of displacement / displacement ratio distribution of n-th frame and (n-1) -th frame" in the flowchart of FIG. This embodiment is also applicable to the first to tenth embodiments.

In this embodiment, after completing the displacement distribution calculation, it is checked whether or not there is an error in the displacement distribution calculation result. If there is an error, the error value is corrected and then the displacement ratio calculation is performed. It is supposed to do. As a result, the result of the displacement rate distribution calculation, which is a differentiation process, is greatly affected by the error in the displacement calculation, and the hardness /
A highly accurate image can be displayed by preventing the accuracy of the elasticity information image from being significantly degraded.

Therefore, first, it is determined whether or not the result of the displacement calculation in step S91 is an abnormal value. In the present embodiment, the living tissue is a viscoelastic body, utilizing the fact that the portion near the portion where the slight displacement is applied is located near the portion where the displacement is applied even after the displacement is applied. Determine outliers.

The displacement distribution calculation result indicates the amount of movement before and after the application of a weak displacement. The calculation unit 25 uses the displacement distribution calculation result as foresight information. For example, assume that a spatial position is set on the X and Y axes and a displacement amount is set on the Z axis, and a graph is created by mapping the displacement distribution calculation result. This graph can be represented as a continuous plane.

The look-ahead information should not have a value that differs significantly from the expected value. Therefore, data indicating a value greatly deviating from the plane on the graph created by the calculation unit 25 can be determined as a calculation error. For example, the calculation unit 25 calculates an average, a variance, and a standard deviation from a displacement calculation result near the determination target, and extracts data having a difference or error of a certain value or more to detect an abnormal value (step S92). .

If the calculating section 25 determines in step S93 that there is an abnormal value, it corrects the abnormal value extracted in step S94. For example, the calculation unit 25 deletes the detected abnormal value, and substitutes an average value of data of a part around the part that gives the abnormal value instead. After correcting the abnormal value in this manner, the displacement rate distribution is obtained (step S95).

The other operation is the same as that of the first embodiment.

As described above, in the present embodiment, a hardness / elasticity information image of a living tissue can be displayed with high accuracy.

[Supplementary Notes] (1) An ultrasonic transducer is provided at the end of the endoscope, and an ultrasonic signal is transmitted and received from the ultrasonic transducer to generate an ultrasonic tomographic image of an object to be measured. In the endoscope system, at least a part of the ultrasonic reflection signal of the measurement object for one screen is stored for at least two screens, and the stored ultrasonic reflection signal is called, and the inter-screen is calculated by the calculation processing. Displacement detecting means for obtaining a displacement distribution of the object to be measured with respect to the distal end portion of the ultrasonic endoscope, a displacement rate detecting means for obtaining a displacement rate distribution from a calculation result of the displacement detecting means, An ultrasonic endoscope system comprising: an imaging unit that images a distribution; and a monitor that displays an image generated by the imaging unit.

(1-1) The ultrasonic endoscope system according to claim 1, wherein said storage means stores an ultrasonic reflection signal at a set frame interval.

(1-2) The ultrasonic endoscope system according to claim 1, wherein said storage means stores ultrasonic reflected signals of successive frames.

(1-3) The ultrasonic endoscope according to additional item 1, wherein the storage means stores an ultrasonic reflection signal at a set interval of one second from the frame rate of the ultrasonic tomographic image. Mirror system.

The purpose of Appendix 1 is to use an ultrasonic endoscope,
It is an object of the present invention to provide an ultrasonic endoscope system capable of imaging elasticity information of a measurement object and using the image for diagnosis.

In the supplementary item 1, a system is configured to store an ultrasonic reflection signal of the same region over two frames of the ultrasonic endoscope and calculate the signal. The system calculates the displacement between two frames and further calculates the displacement rate in the local space. This displacement ratio distribution is displayed as an image.

According to the supplementary item 1, during the examination using the ultrasonic endoscope, information relating to the hardness and elasticity of the living tissue is stored in two.
The effect that a two-dimensional image can be displayed is obtained.

(2) The ultrasonic endoscope system according to claim 1, further comprising a displacement generating means for applying a displacement to the object to be measured.

(2-1) The displacement generating means comprises a balloon attached to the tip of the ultrasonic endoscope, and a medium feeding / discharging means for changing the amount of the ultrasonic transmission medium inside the balloon. The ultrasonic endoscope system according to additional item 2.

(2-2) The ultrasonic endoscope system according to additional item (2-1), wherein the medium feeding / discharging means has a control means for performing control for feeding / discharging the set medium.

(2-3) The ultrasonic endoscope system according to claim 2, wherein the displacement generating means is a medium feeding / discharging means for feeding / discharging the ultrasonic transmission medium from the tip of the ultrasonic endoscope. .

(2-4) The displacement generating means is provided in a forceps channel for inserting forceps provided in an ultrasonic endoscope.
The ultrasonic endoscope system according to claim 2, wherein the ultrasonic endoscope system is a forceps to be inserted.

(2-5) The ultrasonic wave according to additional item (2-4), wherein the displacement generating means is a balloon attached to an end of the forceps protruding from the end of the ultrasonic endoscope. Endoscope system.

An object of the additional item 2 is to provide a means for applying a displacement to a measurement object in an ultrasonic endoscope system capable of imaging elasticity information of the measurement object and using the image for diagnosis.

In the additional item 2, an ultrasonic endoscope system capable of positively applying displacement deformation to an observation target is configured. The displacement / deformation of the measurement object is measured while positively applying a displacement to the measurement object.

According to the additional item 2, there is obtained an effect that the living tissue is positively displaced and, thereby, the information on the hardness and elasticity of the living tissue can be displayed more accurately in a two-dimensional image.

(3) Additional items 1 and 2 characterized by having a reference member which is placed in the ultrasonic observation region of the ultrasonic endoscope under external force together with the object to be measured and is made of a known material. Item 7. The ultrasonic endoscope system according to Item 2.

(3-1) The ultrasonic endoscope system according to claim 3, wherein the reference member is an elastic member.

(3-2) The ultrasonic endoscope system according to item 3, wherein the reference member is attached to a balloon attached to the ultrasonic endoscope.

(3-3) The ultrasonic endoscope system according to item 3, wherein the reference member is detachably attached to the ultrasonic endoscope.

(3-4) The ultrasonic endoscope according to item 3, wherein the reference member is attached to a tip of a forceps inserted into a forceps channel provided in an ultrasonic endoscope. Mirror system.

(3-5) The ultrasonic endoscope system according to item (3-4), further comprising a protection member provided near the reference member for protecting the reference member.

(3-6) The ultrasonic imaging apparatus according to item (3-5), wherein the protection member is operated by operating means provided at the other end of the forceps to expose the hardness reference member. Endoscope system.

An object of the additional item 3 is to provide a device which can absolutely evaluate displayed elasticity information.

In the additional item 3, an ultrasonic endoscope system having a member that undergoes displacement / deformation simultaneously with the object to be measured is configured. The displacement / deformation amount of the measurement object is standardized by the displacement / deformation amount of the member.

According to the additional item 3, there is an effect that information on hardness and elasticity of the living tissue can be quantitatively compared.

(4) The ultrasonic endoscope is a forward-looking ultrasonic endoscope having an ultrasonic observation plane parallel to the tip axis, and a balloon that expands in the space in the visual field direction of the ultrasonic endoscope. The ultrasonic endoscope system according to claim 1, further comprising:

An object of the additional item 4 is to provide means for applying a displacement to a measurement object in an ultrasonic endoscope system capable of imaging elasticity information of the measurement object and using the image for diagnosis.

In the additional item 4, an ultrasonic endoscope system capable of positively applying a displacement deformation to an observation object is configured. The displacement / deformation of the measurement object is measured while positively applying a displacement to the measurement object.

According to the additional item 4, it is possible to easily press the living tissue, and thereby, it is possible to more accurately display information on the hardness and elasticity of the living tissue in a two-dimensional image.

(5) An input device operable by an operator for generating a signal for performing measurement is provided separately from the ultrasonic endoscope, wherein the input means is provided separately from the ultrasonic endoscope. An ultrasonic endoscope system according to one of the preceding claims.

(5-1) The ultrasonic endoscope system according to claim 5, wherein said input means is a foot switch.

(5-2) The ultrasonic endoscope system according to claim 5, wherein said input means is a voice recognition means.

(5-3) The ultrasonic endoscope system according to claim 5, wherein said input means is a line-of-sight input means.

(5-4) The ultrasonic endoscope system according to claim 5, wherein said input means is a hand switch.

(5-5) The ultrasonic endoscope system according to item 5, wherein the input means is a keyboard.

[0208] An object of the additional item 5 is to provide an ultrasonic endoscope system capable of evaluating elasticity of an object with good operability.

[0209] In Supplementary Note 5, a switch for starting measurement of information related to hardness / elasticity of a measurement object is formed separately from the ultrasonic endoscope. When the measurement of information related to the hardness / elasticity of the measurement object is started, there is no need to change the holding of the ultrasonic endoscope, and without affecting the observation field of the ultrasonic endoscope, the switch can be used. To operate.

According to the additional item 5, since the displacement of the visual field during the observation by the ultrasonic endoscope can be reduced, the information on the hardness and elasticity of the living tissue can be displayed more accurately in a two-dimensional image.

(6) The displacement detecting means for finding the displacement distribution includes first means for finding a displacement in the first area,
A second means for obtaining a displacement of a second area set near the first area based on the first area displacement; a third means for replacing the second area with the first area; Or a fourth means for repeating the third means, a fifth means for repeating the first to fourth means, and a correction means for correcting the displacement calculation result. Item 1
Ultrasonic endoscope system.

(6-1) The ultrasonic endoscope system according to claim 6, wherein said correction means is means for restricting an output with respect to a large displacement calculation result.

(6-2) The correction means wherein the relationship between input and output changes smoothly.
Ultrasonic endoscope system.

The purpose of the additional item 6 is to improve calculation accuracy.

In Supplementary Item 6, when the amount of the displacement calculation result is clearly larger than the expected displacement amount, the amount is greatly reduced, and when the amount of the displacement calculation result is small, the amount is almost reduced. A function that does not affect the displacement calculation result. The value after the operation is calculated as a displacement calculation result to be used later.

According to the additional item 6, by correcting the displacement position of the calculation result to increase the displacement calculation accuracy, more accurate information on the hardness and elasticity of the living tissue can be obtained.
Can display two-dimensional images.

(7) There is provided a rotational displacement detecting means for retrieving the ultrasonic reflection signal stored in the storage means and calculating the rotational displacement amount of the ultrasonic endoscope between the screens. The ultrasonic endoscope system according to claim 1, further comprising a displacement detecting means for calculating a displacement distribution by evaluating a displacement amount in advance.

(7-1) The ultrasonic endoscope according to claim 8, wherein said displacement detecting means cuts out the ultrasonic signal stored in said storage means by shifting in advance by the output of said rotational displacement detecting means. system.

The purpose of the additional item 7 is to improve calculation accuracy.

In Appendix 7, the amount of rotation of the visual field of the ultrasonic endoscope is determined. This value is used as the displacement amount of the tissue in advance, and the displacement calculation range is shifted to calculate the displacement.

According to the additional item 7, it is possible to improve the displacement calculation accuracy by calculating the rotation amount of the observation position of the ultrasonic endoscope in advance and making the displacement calculation spaces more consistent with each other. Thereby, it is possible to more accurately display information on the hardness and elasticity of the living tissue in a two-dimensional image.

(8) The ultrasonic endoscope has a mechanism for generating an ultrasonic tomographic image by moving an ultrasonic transducer by a mechanical mechanism, and calling an ultrasonic reflection signal stored in the storage means, It has a rotational deviation detecting means for evaluating the rotational deviation of the ultrasonic transducer between the screens, and has a displacement detecting means for evaluating the output value of the rotational deviation means as a prior displacement to obtain a displacement distribution. 7. The ultrasonic endoscope system according to claim 1, wherein

(8-1) The ultrasonic endoscope according to additional item 8, wherein the displacement detecting means cuts out the ultrasonic signal stored in the storage means by shifting in advance by the output of the rotation deviation detecting means. system.

(8-2) The ultrasonic endoscope system according to additional item 8, wherein said rotation deviation detecting means evaluates a correlation coefficient distribution of an ultrasonic signal between screens.

The purpose of the additional item 8 is to improve the calculation accuracy.

In the additional item 8, the rotation amount of the visual field of the ultrasonic endoscope is obtained. This value is used as the displacement amount of the tissue in advance, and the displacement calculation range is shifted to calculate the displacement.

According to Supplementary Item 8, even in a mechanical scan type ultrasonic endoscope apparatus having low stability with respect to the direction in which an ultrasonic reflection signal is obtained, the displacement, deformation amount, and Hardness can be determined.

(9) The displacement detecting means performs a Fourier transform on a part of the first screen data stored in the storage means, and a Fourier transform on a part of the second screen data. Second Fourier transform means;
Cross-spectrum calculating means for taking the product of each element by taking one complex conjugate of one Fourier transform result, element detecting means for detecting the largest element among the products of the respective elements, and detecting the largest element and another element Element extraction means for comparing the size of the object and extracting only elements larger than a certain ratio, and displacement detection means for obtaining a displacement distribution of the measurement object with respect to the ultrasonic endoscope tip based on the extracted data. The ultrasonic endoscope system according to additional item 1, characterized in that:

(9-1) The ultrasonic endoscope system according to attachment 9, wherein the search range for the maximum value of the element is limited.

(9-2) The ultrasonic endoscope system according to claim 9, wherein the range in which the maximum value of the element is searched is a frequency element close to the center frequency of the ultrasonic transducer.

(9-3) The ultrasonic endoscope according to claim 9, wherein the range for searching for the maximum value of the element is a frequency range of about ± 10% of the center frequency from the center frequency of the ultrasonic transducer. Mirror system.

(9-4) The boundary value for judging element selection / non-selection of the element extracting means is from the maximum element value of -9 dB to-
The ultrasonic endoscope system according to claim 9, wherein the distance is between 2 dB.

(9-5) The ultrasonic endoscope system according to attachment 9, wherein the element extracting means extracts only a value larger than -3 dB of the largest element.

The purpose of the additional item 9 is to obtain an accurate displacement calculation result while reducing the calculation amount.

In the additional item 9, means for discriminating between data that is not valid for displacement calculation and data that is valid is provided, and calculation is performed only with valid data.

According to the additional item 9, the number of data used for calculation can be reduced. As a result, the calculation time can be reduced.

(10) The displacement detecting means performs first Fourier transform on a part of the first screen data stored in the storage means and Fourier transforms a part of the second screen data. Second Fourier transform means, element selecting means for selecting only preset frequency elements,
Cross spectrum calculating means for taking the product of each element by taking the complex conjugate of one of the extracted frequency elements, and displacement detecting means for obtaining the displacement distribution of the object to be measured with respect to the tip of the ultrasonic endoscope based on the product of each element The ultrasonic endoscope system according to claim 1, comprising:

(10-1) The ultrasonic endoscope system according to additional item 10, wherein the selected element is an element near the center frequency of the ultrasonic transducer.

(10-2) The selected element is an element near the center frequency of the ultrasonic transducer with respect to the direction parallel to the transmission direction of the ultrasonic wave and the direction perpendicular to the transmission direction of the ultrasonic wave. The ultrasonic endoscope system according to additional item 10, wherein the ultrasonic endoscope system is a low-frequency element.

(10-3) As the range of the selected element and the frequency in the direction perpendicular to the ultrasonic transmission direction increase, the frequency width in the ultrasonic transmission direction becomes narrower. 10-2) An ultrasonic endoscope system.

The purpose of the additional item 10 is to obtain an accurate displacement calculation result while reducing the calculation amount.

In the additional item 10, means for discriminating between data that is not valid for displacement calculation and data that is valid is provided, and calculation is performed using only valid data.

According to the additional item 10, the number of data used for calculation can be reduced. As a result, the calculation time can be reduced.

(11) An ultrasonic endoscope system in which an ultrasonic transducer is provided at the end of the endoscope, and an ultrasonic signal of the ultrasonic transducer is transmitted and received to generate an ultrasonic tomographic image of an object to be measured. A storage means for storing at least a part of an ultrasonic reflection signal from a measurement object for one screen for at least three screens, and calling up at least two times repeatedly for each of the stored ultrasonic reflection signals for two screens. A displacement detection means for calculating a displacement distribution of the measurement object between the screens with respect to the distal end portion of the ultrasonic endoscope in the calculation processing, and a calculation result of the displacement detection means repeated at least twice,
A displacement rate detecting means for obtaining a displacement rate distribution, at least two displacement rate distributions obtained by the displacement rate detecting means are imaged, an image forming means, and at least two images generated by the image forming means are continuously displayed. An ultrasonic endoscope system comprising a monitor.

(11-1) An ultrasonic endoscope system according to item 1, wherein said storage means stores an ultrasonic reflection signal at a set frame interval.

(11-2) The ultrasonic endoscope system according to additional item 1, wherein said storage means stores ultrasonic reflected signals of consecutive frames.

(11-3) The ultrasonic endoscope according to additional item 1, wherein said storage means stores an ultrasonic reflection signal at a set interval of one second from a frame rate of an ultrasonic tomographic image. Mirror system.

The purpose of the additional item 11 is to display a displacement rate distribution image as a moving image. In addition, it is to improve the accuracy by constructing a displacement distribution image using two or more sets of data.

In the additional item 11, at least three or more pieces of data are stored and displacement calculation is performed as needed, so that a displacement distribution image is continuously constructed and continuously displayed.

According to the additional item 11, information on the hardness and elasticity of the living tissue can be displayed as a continuous image.

(12) Additional items 1 to 11, further comprising: a judging means for judging the presence or absence of an abnormal value in the displacement distribution calculation result; and a displacement rate detecting means for removing the abnormal value to obtain a displacement rate distribution. Any one of the ultrasonic endoscope systems.

The purpose of the additional item 12 is to improve the accuracy of an image to be provided.

In Additional Item 12, from the displacement calculation result,
Assess if there is a change situation that cannot happen in reality,
If such a calculation result exists, the data is removed or replaced with an appropriate value, thereby improving the accuracy of the displacement rate distribution result and improving the provided image accuracy.

According to the additional item 12, it is possible to reduce noise caused by an error in displacement calculation in an image representing information on hardness and elasticity of a living tissue.

(13) Judgment means for judging the presence or absence of an abnormal value in the displacement distribution calculation result, evaluation means for evaluating the frequency of occurrence of the abnormal value, and when the frequency of occurrence of the abnormal value is larger than the set boundary value. The ultrasonic endoscope system according to any one of additional items 1 to 11, further comprising a displacement rate detecting unit that stops the displacement rate calculation process.

The purpose of the additional item 13 is to improve the accuracy of an image to be provided.

In Additional Item 13, from the displacement calculation result,
Assess if there is a change situation that cannot happen in reality,
If such a calculation result exists, the data is removed or replaced with an appropriate value, thereby improving the accuracy of the displacement rate distribution result and improving the provided image accuracy.

According to the additional item 13, it is possible to reduce noise caused by an error in displacement calculation in an image representing information on hardness and elasticity of a living tissue.

(14) An image processor which receives at least one of an ultrasonic tomographic image, an ultrasonic endoscope optical image, and an image signal generated by the imaging means is provided. The ultrasonic endoscope system according to any one of additional items 1 to 13, wherein the image selectively output to the monitor and displayed on the monitor.

The purpose of the additional item 14 is to provide a display method suitable for displaying a displacement rate distribution image (hardness distribution image).

In Supplementary Item 14, a plurality of inputs are provided to a processor for displaying an image on a monitor, and an ultrasonic tomographic image, an ultrasonic tomographic image at the time of measurement, an ultrasonic endoscope optical image, a displacement rate distribution image (hardness) Image) or a plurality of images is selected, and an image in a form suitable for observation and diagnosis is displayed on a monitor.

According to the additional item 14, image information necessary for observation / diagnosis can be displayed and provided at once in a suitable form.

(15) An image processor which receives at least one of an ultrasonic tomographic image, an ultrasonic endoscope optical image, and an image signal generated by the imaging means is provided. The ultrasonic endoscope system according to any one of additional items 1 to 13, wherein at least two of the images obtained are simultaneously output to the monitor and displayed on the monitor.

The purpose of the additional item 15 is to provide a display method suitable for displaying a displacement rate distribution image (hardness distribution image).

In Supplementary Item 15, a plurality of inputs are provided to a processor for displaying an image on a monitor, and an ultrasonic tomographic image, an ultrasonic tomographic image at the time of measurement, an ultrasonic endoscope optical image, a displacement rate distribution image (hardness) Image) or a plurality of images is selected, and an image in a form suitable for observation and diagnosis is displayed on a monitor.

According to the additional item 15, it is possible to display and provide image information necessary for observation / diagnosis at a time in a suitable form.

(16) At least one of a current ultrasonic tomographic image, an ultrasonic endoscopic optical image, and an ultrasonic tomographic image at the time of measuring an ultrasonic signal used for calculating a displacement ratio distribution, and An image processor that receives the image signal generated by the means as an input, and selectively outputs at least one of the input images to the monitor and displays the image on the monitor. An ultrasonic endoscope system according to any one of 1 to 13.

(16-1) The ultrasonic tomographic image at the time of measuring the ultrasonic signal used for calculating the displacement rate distribution and the image generated by the imaging means are superimposed and displayed. Ultrasonic endoscope system.

An object of the additional item 16 is to provide a display method suitable for displaying a displacement rate distribution image (hardness distribution image).

In Appendix 16, a plurality of inputs are provided to a processor for displaying an image on a monitor, and an ultrasonic tomographic image, an ultrasonic tomographic image at the time of measurement, an ultrasonic endoscope optical image, a displacement rate distribution image (hardness distribution image) Image) or a plurality of images is selected, and an image in a form suitable for observation and diagnosis is displayed on a monitor.

According to the additional item 16, image information necessary for observation / diagnosis can be displayed and provided at once in a suitable form.

[0272]

As described above, according to the first aspect of the present invention,
According to this method, an effect is obtained in which information related to the hardness and elasticity of a living tissue can be displayed in a two-dimensional image during an examination using an ultrasonic endoscope.

Further, according to the second aspect of the present invention, the living tissue is positively displaced, and
The effect is obtained that the information on the hardness and elasticity of the living tissue can be displayed more accurately in a two-dimensional image.

Further, according to the third aspect of the present invention, there is an effect that information relating to hardness and elasticity of a living tissue can be quantitatively compared.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system according to a first embodiment of the present invention.

FIG. 2 is an internal block diagram of the ultrasonic observation apparatus 2 in FIG.

FIG. 3 is an explanatory diagram showing a distal end portion of the ultrasonic endoscope 1.

FIG. 4 is a perspective view showing the appearance of the ultrasonic endoscope 1.

FIG. 5 is a flowchart illustrating the operation.

FIG. 6 is a flowchart showing an internal flow of “displacement / displacement rate calculation processing” in FIG. 5;

FIG. 7 is an explanatory diagram for explaining data cut out for calculation processing.

FIG. 8 is an explanatory diagram showing a distal end portion of a balloon ultrasonic endoscope employed in the second embodiment.

FIG. 9 is a flowchart showing an internal flow of “displacement / displacement ratio calculation processing”.

FIG. 10 is a flowchart for explaining displacement calculation employed in a third embodiment of the present invention.

FIG. 11 is a flowchart for explaining displacement calculation employed in a third embodiment of the present invention.

FIG. 12 is an explanatory diagram showing an ultrasonic endoscope distal end portion 71 employed in a fourth embodiment of the present invention.

FIG. 13 is an explanatory diagram showing a distal end portion of an ultrasonic endoscope employed in a fifth embodiment of the present invention.

FIG. 14 is an explanatory diagram showing a distal end portion of an ultrasonic endoscope employed in a sixth embodiment of the present invention.

FIG. 15 is an explanatory diagram showing an ultrasonic endoscope distal end portion employed in a seventh embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a distal end portion of an ultrasonic endoscope employed in an eighth embodiment of the present invention.

FIG. 17 is a flowchart for explaining displacement calculation employed in a ninth embodiment of the present invention.

FIG. 18 is a flowchart showing an operation flow employed in the tenth embodiment of the present invention.

FIG. 19 is a flowchart showing an operation flow employed in an eleventh embodiment of the present invention.

FIG. 20 is a flowchart showing an operation flow employed in a twelfth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic endoscope, 2 ... Ultrasonic observation apparatus, 5 ... Monitor, 7 ... Endoscope image processor, 8, 9 ... Input part, 11
... light source, 27 ... water pump, 45 ... suction pump.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06T 1/00 290 G06T 1/00 290D H04N 7/18 H04N 7/18 M Q F term (Reference) 2H040 GA10 GA11 4C061 AA00 BB00 CC00 DD03 FF35 FF36 HH04 HH05 HH51 JJ11 JJ17 4C301 AA02 BB03 BB28 BB30 CC02 DD06 DD11 EE11 EE20 FF05 FF15 GA15 GB03 DA06 GC22 GD10 JB03 JB30 JB34 BAB12 JB03 JB38 JB03 A05 AA05 CA08 CC07 CF05 EB05 FC15 FE17 GA04 GB01 HA12

Claims (3)

[Claims] 1. An ultrasonic endoscope system in which an ultrasonic transducer is provided at a distal end portion of an endoscope, and an ultrasonic signal is transmitted and received from the ultrasonic transducer to generate an ultrasonic tomographic image of an object to be measured. A storage unit for storing at least a part of the ultrasonic reflection signal of the measurement object for one screen for at least two screens; calling the stored ultrasonic reflection signal, and calculating the measurement object between the screens by a calculation process Displacement detection means for obtaining a displacement distribution with respect to the tip of the ultrasonic endoscope; displacement rate detection means for obtaining a displacement rate distribution from a calculation result of the displacement detection means; and imaging of the displacement rate distribution obtained by the displacement rate detection means. An ultrasound endoscope system, comprising: an imaging unit that performs an image processing; and a monitor that displays an image generated by the imaging unit. 2. The ultrasonic endoscope system according to claim 1, further comprising a displacement generating means for applying a displacement to the object to be measured. 3. A reference member which receives an external force together with the object to be measured, is arranged in an ultrasonic observation region of an ultrasonic endoscope, and is formed of a known material.
Or the ultrasonic endoscope system according to any one of 2.