JPH02189139A - Internal visual ultrasonic diagnosing device - Google Patents

Abstract

PURPOSE:To enable the increase of the scanning space region of a probe by a method wherein a guide member to regulate movement of a probe having an ultrasonic vibrator situated at the tip part on the insertion side thereof is mounted on the tip part of an endoscope in a state to be coupled to a channel. CONSTITUTION:A probe 40 having an ultrasonic vibrator 70 located on its tip is inserted in a body cavity through a channel 50 situated in a state to be communicated to the flexible part of an endoscope 1. The ultrasonic vibrator 70 at the tip on the insertion side of the probe 40 inserted in the channel 50 is moved through a piston 33, a cylinder 32, and oil, with which a transmission shaft (transmission pipe) 60 is sealed, through drive of a piezoelectric actuator 34, and a moving direction is regulated by a guide member 92. The ultrasonic vibrator performs scanning through a range of from a linear scan region to a convex scan region. This constitution enables the sharp increase of a visual field without damaging an organism.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscopic ultrasound diagnostic device that is used by being inserted into a channel of an endoscope.

[Conventional technology]

Conventionally, ultrasound endoscopes have been used to perform ultrasound diagnosis by incorporating an ultrasound transducer into the insertion tip of the endoscope and emitting ultrasound waves from this ultrasound transducer to the diagnostic area of the subject. There is. This type of ultrasonic endoscope is, for example, a flexible rotary endoscope in which an ultrasonic transducer is rotatably attached to the tip of the insertion section of the endoscope, and this ultrasonic transducer is extended through the insertion section of the endoscope. There is a mechanical scanning type that is rotated by a motor via a shaft. In addition, there is electronic scanning in which a large number of ultrasonic transducers are arranged in an array at the insertion tip of an endoscope, and these transducers are driven with signals having a predetermined positional relationship to perform linear scanning or sector scanning. There are formulas, etc.

By the way, the insertion section of the ultrasonic endoscope that is inserted into the body cavity has an image guide, light guide, forceps channel, air supply and
There is a water supply channel, etc., and in addition, an ultrasonic transducer, a conducting wire connected to this transducer, and, in the case of a mechanical scanning method, a flexible rotating shaft for transmitting rotational force to the transducer, etc. are built-in. Therefore, the insertion portion of the endoscope inevitably has a large diameter.

However, if the insertion portion of the endoscope becomes large, there is a problem in that it causes pain to the subject.

Therefore, a probe with a built-in ultrasonic transducer at its tip is inserted into the body cavity through the endoscope's original forceps channel, and the ultrasonic transducer is moved in the insertion direction within the probe to create a machine. I'm trying to do linear scanning.

[Problem to be solved by the invention]

In the endoscopic ultrasound diagnostic device described above, the ultrasound probe is inserted through the forceps channel etc. that the endoscope originally has, so there is no need to increase the diameter of the endoscope.
Therefore, there is no need to worry about causing pain to living organisms due to the large diameter.

However, this type of endoscopic ultrasound diagnostic apparatus has a problem in that the diagnostic field of view is narrow because the ultrasound transducer can only be translated in the insertion direction within the probe. In order to enlarge the field of view, it is necessary to make the probe protrude more than the tip of the endoscope.

However, if the probe protrudes too much, there is a risk of pressing on or damaging the wall around the diagnostic site of the living body.

Furthermore, in the case of a so-called linear scan method using translational movement, it is not possible to secure a forward field of view. In order to observe the front field of view, the tip must be curved to function as an endoscope. but,
If there is not enough spatial area for curving, there is a risk of damaging the internal walls of the body.

Further, in the conventional endoscopic ultrasonic diagnostic apparatus, a scanning drive section for moving an ultrasonic transducer in the insertion direction within the probe is provided in the scanning section of the endoscope. Therefore, when a scan drive unit is configured with a linear motion conversion unit consisting of a motor, reduction unit, lead screw, nut, etc., the scan drive unit incorporates all of these parts, making it difficult to reduce size and weight. become.

Additionally, there is a method of driving the vibrator by pulling a wire, but this method requires a long wire to be routed within the channel of the endoscope, which poses problems such as an increase in load due to friction with the internal wall of the living body.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to make it possible to obtain a large diagnostic field of view without enlarging the scanning spatial area of the probe, to make the scanning drive unit smaller and lighter, and to perform more stable ultrasound diagnosis. An object of the present invention is to provide an endoscopic ultrasound diagnostic device.

[Means for Solving the Problems] In order to solve the above problems and achieve the objects, the present invention takes the following measures. That is, a channel provided in communication with the flexible part of the endoscope, a flexible probe that can be inserted into this channel, and an ultrasonic transducer provided at the insertion side tip of this probe. A guide member for regulating movement of the probe is provided at the distal end of the endoscope and connected to the channel.

Note that it is desirable that the guide member has an arc shape.

In addition, in order to achieve the above purpose, we have developed a flexible probe that can be inserted into the channel of an endoscope, and a superstructure that is movable along its longitudinal direction at the insertion-side distal end of the probe. a sonic transducer, a drive means for moving the ultrasonic transducer in the longitudinal direction within the probe, and a driving force provided in communication within the probe so as to connect the drive means and the ultrasonic transducer. A means of communication was also provided.

The driving means includes a piston, a cylinder, and a piezoelectric actuator that moves the piston, and the driving force transmitting means includes a transmission tube whose both ends are connected to the cylinder and the ultrasonic vibrator, respectively, and It is preferable that the fluid is sealed in a transmission pipe.

Furthermore, in order to achieve the above object, at least one of the channel of the endoscope or the probe is provided with a detection means for detecting the position and/or direction of the ultrasonic transducer.

Furthermore, in order to achieve the above object, a plurality of ultrasonic transducers each capable of independently transmitting and receiving ultrasonic waves are provided at the insertion-side distal end of the probe.

[Effect]

By taking the above measures, the following effects are achieved. That is, a probe equipped with an ultrasonic transducer at its tip can be inserted into the body cavity through a channel provided in communication with the flexible part of the endoscope, and the ultrasonic transducer inserted into the body cavity can be inserted into the body cavity. is the distal end of the endoscope, and the direction of movement is regulated by a guide member connected to the channel, allowing continuous movement from, for example, linear scanning to convex scanning.

Furthermore, by taking the above measures, the ultrasonic transducer provided at the insertion side tip of the probe inserted into the channel of the endoscope receives the driving force from the driving means via the driving force transmitting means. The transmitted driving force causes the probe to be moved in the longitudinal direction within the probe.

Since the driving means is composed of a piston, a cylinder, and a piezoelectric actuator for moving the piston, the scanning driving section can be made smaller and lighter.

Further, since the driving force transmission means is constituted by a transmission pipe whose both ends are connected to the cylinder and the ultrasonic vibrator, respectively, and a fluid sealed in the transmission pipe, the driving force is transmitted by the fluid, and the driving force is transmitted by the wire, etc. It is possible to eliminate frictional deterioration due to

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the device of the present invention attached to an endoscope. Reference numeral 1 shown in the figure is an endoscope, and an operating section 2. Insertion part 3. The main component is Universal Code 4.

The insertion section 3 includes a flexible section 5. Curved portion 6. It consists of a tip 7. An image guide, a light guide, etc. are built in from the operating section 2 to the insertion section 3. The incident end of the light guide is connected to a light source unit (not shown) via a universal cord 4. The light from this light source unit is irradiated from the tip 7 of the endoscope via the light guide,
Illuminating the inside of the body cavity. The image inside the body cavity is then observed from the eyepiece 8 via an image guide. Further, reference numeral 9 denotes a forceps port, and a channel formed along the longitudinal direction inside the insertion portion 3 is communicated with the forceps port 9. Then, the forceps are inserted into the body cavity from the forceps port 9 through the channel to collect tissue.

In this embodiment, the ultrasound diagnostic apparatus 1 uses the forceps port 9 of the endoscope 1 and the channel communicating with the forceps port 9.
0 is installed. The ultrasonic diagnostic apparatus 10 includes a probe that can be inserted into the forceps port 9 and the channel and has an ultrasonic transducer in its tip, and a scanning drive unit that moves the ultrasonic transducer in the longitudinal direction within the tip of the probe. 12, a connecting member 13 that connects the scan drive section 12 to the forceps port 9, and a connector 14 that connects the scan drive section 12 to a drive controller.

The specific configuration of this embodiment will be described below with reference to FIGS. 2 to 5.

FIG. 2 is a sectional view showing the structure of the forceps mouth 9 and the scanning drive section 12. As shown in FIG. A connecting member 14 is attached to a screw 21 at the forceps opening 9.
It is attached with screws. The connecting member 14 slidably and rotatably holds the scanning drive section 14 via an elastic friction body 22 made of rubber or the like on its inner peripheral surface.

The scanning drive unit 12 includes an outer cylinder 31, a cylinder 32 formed inside the outer cylinder 31, a piston 33 that slides under the pressure of fluid (air or liquid) sealed in the cylinder 32, and the piston 33. and a laminated piezoelectric actuator 34 interposed between the upper end surface of the cylinder 32 and the upper end surface of the inner wall of the cylinder 32. Note that a piston ring 35 made of a sealing material is attached to the piston 33 to improve airtightness with the cylinder 32. Further, the proximal end portion of the probe 40 is attached to the lower end portion of the scanning drive unit 12, and the distal end portion 41 is inserted into the channel 50 of the endoscope 1 through the forceps port 9. has reached. A transmission shaft 60 made of a coil shaft or a wire and functioning as a driving force transmission means is inserted into the probe 40. One end of the transmission shaft 60 is airtightly attached to the lower end of the cylinder 32, and a fluid-sealed region within the cylinder 32 and a fluid-sealed region formed in the longitudinal direction within the transmission shaft 60 communicate with each other. Further, the tip portion 4 of the probe 40 is attached to the other end of the transmission shaft 60.
The ultrasonic transducer 70 provided in 1 is attached.

The signal cable 61 extending from this ultrasonic transducer 70 is
It passes through the transmission shaft 60 and is taken out via the scanning drive section 12, and further connected to the control section 81 of the transmitting/receiving device 80 via the connector 13. Note that the signal cable 61 may be routed outside without passing through the inside of the probe 40.

FIG. 3 is a cross-sectional view of the distal end of the endoscope 1 through which the probe 40 is inserted. As shown in the figure, the probe 40
is inserted into the channel 5o of the endoscope 1, and the tip 41 of the probe 40 is made to protrude from the tip 7 of the endoscope 1, and ultrasonic diagnosis is performed in this state.

FIG. 4 is a cross-sectional view showing the structure of the tip of the probe. An ultrasonic transmission/reception window 42 is provided on the side surface of the probe tip 41 along the longitudinal direction of the probe. Further, an ultrasonic transducer 70 built into the probe tip 41 is held movably in the longitudinal direction of the probe by a holding member 71 facing the ultrasonic transmission/reception window 42 . This holding member 71 is connected to the other end of the transmission shaft 60 via a bellows joint 72. Note that an ultrasonic conducting medium 73 is provided along the vibration range on the surface of the ultrasonic transmitting/receiving window 42 that faces the vibrator 70 .

FIG. 5 is a block diagram showing the configuration of the transmitting/receiving device 80. As shown in FIG. The received signal containing the image information of the diagnostic section received by the transducer 70 is transmitted to the cable 61. Transmitting/receiving device 80 via connector 13
The signal is input to the reception amplifier circuit 81, amplified, and output to the digital scan converter 82. The digital scan converter 82 converts the input received signal into a signal for displaying an image, and then outputs it to the display device 83. Display device 83
An image of the diagnostic department is displayed. On the other hand, the controller 85 of the control device 84 sends a predetermined transmission timing signal to the transmission circuit 86 and also outputs a control signal for controlling the drive of the piezoelectric actuator 34 to the drive circuit 87. The actuator 34 is driven by this control signal. Further, the controller 85 controls the actuator 3
In synchronization with the control signal that gives the operation amount of 4, a signal for giving scan timing to the digital scan converter 82 is transmitted, and the digital scan converter 82 is instructed to take in the received signal. In addition. , the timing of capturing each scanning line is also determined by a command signal from the controller 85.

The endoscopic ultrasonic diagnostic device described above operates as follows. That is, when the actuator 34 is driven to expand or contract by a control signal output from the controller 85, the piston 33 moves in response to the movement of the actuator 34.

Then, fluid pressure corresponding to the amount of movement of the piston 33 is applied to the holding member 71 via the fluid in the transmission shaft 60 and the fluid in the bellows joint 72. Therefore, the ultrasonic transducer 70 held by the holding member 71 moves along the longitudinal direction of the probe and performs linear scanning.

At this time, since the transmission shaft 60 and the holding member 71 are connected via the expandable bellows joint 72, the movement of the holding member 71 (vibrator 70) can be accommodated. Further, the amount of movement of the vibrator 70 can be calculated from the ratio of the area of the upper end surface of the holding member 71 in contact with the fluid and the area of the end surface of the piston 33.

This surface-to-surface ratio is defined as the radius of the cross-section of the probe tip 41 as 'l+', the total amount of movement (width of field) Ft, the radius of the cross-section of the piston 33 in the scanning drive unit 12 as '2°, and the amount of movement as g2. Then, it can be expressed as rx 2II 1-r22D2. Therefore, from the actual scope shape, for example,
r】-1,5am, fl 1-30tara, fl
If it is 2-1 mm, the piston radius r2 is r2m8
．． 2mm, and the piston diameter may be φ1B, 4mm. Although it is not appropriate for the laminated piezoelectric actuator 34 to have a large stroke depending on the number of laminated layers, the generated force is large, so the piston movement amount is small, and if the cross-sectional area is secured, it can be easily miniaturized. .

As described above, according to this embodiment, the scanning drive section 12 is connected to the cylinder 32. Piston 33. Since it is configured with the laminated piezoelectric actuator 34, the scan drive unit 12 can be made smaller and lighter. Also, a transmission pipe 6 is used as a drive transmission means.
Since the driving force is transmitted as fluid pressure using a wire, there is no need to worry about an increase in frictional force as in the case of using a wire, and the ultrasonic diagnostic range can be expanded.

Next, FIGS. 6 to 21 show modified examples of the tip of the probe.
This will be explained with reference to the figures.

FIG. 6 is a diagram showing an example in which an arc-shaped probe guide for regulating the movement of the probe is provided at the distal end of the endoscope. Reference numeral 90 shown in the figure is a hard part of the distal end of the endoscope. A linear channel 91 is formed in this hard part 90,
Furthermore, a probe guide 92 having an arcuate channel (curvature channel) for regulating the movement of the probe 40 is connected to the linear channel 91 .

As shown in FIG. 7, the probe guide 92 is designed to be larger than the diameter of the probe tip 41 so that the probe 40 can be moved along the curvature without blocking the ultrasonic waves transmitted from the transducer 70. A groove 93 having a slightly small opening is formed. Further, on both sides of the curvature channel (groove 93) of the probe guide 92, end surfaces 94 of the light guide are provided.
and an end face 95 of the image guide.

According to this configuration, the probe guide 92 in which the curvature channel is formed is connected to the linear channel 91 and provided at the distal end of the endoscope. It draws an arcuate trajectory, making both linear and convex scanning possible.

Therefore, it is possible to significantly expand the field of view.

FIG. 8 is a diagram showing an example in which a deflection prevention adapter is provided at the channel tip of the endoscope tip.

As shown in the figure, a deflection prevention adapter 100 is provided inside the channel tip of the endoscope tip 7, and the probe 40 made of resin with a small coefficient of friction is held at multiple points. Because probe 40 is channel 5
Since the probe 40 is inserted into the inner wall of the channel 50, it is not possible to bring the probe 40 into close contact with the inner wall of the channel 50. Therefore, at the distal end portion 7 of the endoscope, a gap is created between the inner surface of the channel 50 and the probe 40. If such a gap exists, the position of the probe 40 cannot be fixed, and the probe 40 will be bent.

Therefore, by adding a deflection prevention adapter 100, the probe 40 at the tip 7 of the endoscope is connected to the plurality of contacts PL, P2.
．． Hold it at P3 and straighten it into a straight line.

By doing this, the position of the probe tip 41 is determined, and the vibrator 70 can be moved with high precision.

FIGS. 9(a) and 9(b) are views showing an example in which a shape memory alloy is provided at the tip of the probe. In this example, an ultrasonic transducer 70 is provided within the tip 41 of the flexible probe 40 so as to be movable in the longitudinal direction.

The ultrasonic transducer 70 mechanically linearly scans the transducer 70 via a pulling wire 111 extending inside the probe 40 . Note that 112 is a signal line, one end of which is connected to the vibrator 70, and the other end connected to an ultrasonic transmitter (not shown).

In addition, a shape memory alloy (hereinafter referred to as SMA) 1 that memorizes a straight state is provided on the opposite side of the ultrasonic wave transmitting and receiving side of the vibrator 70.
13 are provided along the longitudinal direction of the probe 40. This 5MA 113 is connected to a power supply device (not shown) via a lead wire 114. Then, current is selectively supplied to the 5MA 113 from this power supply device. Figure 9 (
a) shows a state in which current is supplied. In addition, 5MA11
3 is in the initial state where no current is supplied, as shown in Figure 9 (b
), it has flexibility. It may be simply an elastic body in the sense that it has flexibility when inserted and straightens after insertion.

In this embodiment, the probe 40 is inserted into the channel of the endoscope with the 5MA113 in the initial state, and once the probe 40 has passed through the channel, the power supply
A current is supplied to 13.

When current is supplied to 5MA113, 5
MA113 becomes straight.

Therefore, even when using a flexible probe 40, the probe tip 41 is fixed without sagging.
The vibrator 70 within the probe 40 can be moved linearly with high precision.

FIGS. 10(a) and 10(b) are diagrams showing an example in which a plurality of suction cups are formed on the probe tip 41. Note that Figure (a) is a front view of the probe tip seen from the probe insertion side;
Figure (b) is a side sectional view of the tip of the probe. An ultrasonic transducer 70 is provided inside the probe 40 so as to be movable in its longitudinal direction, and a suction cup 120 having a suction channel is provided on the side of the ultrasonic wave transmitting/receiving surface of the transducer 70 so as to sandwich the transducer 70 therein. Multiple formations. The suction channel communicates with the suction device via a connected suction tube (for example, a silicone tube).

Therefore, when the suction cup 120 exerts a suction action after the probe tip 41 is brought into close contact with the body cavity wall 121, the probe tip 41 is attracted to the body cavity wall 121. Therefore, by moving the probe tip 41 along the body cavity wall 121, which is the region of interest in the ultrasound diagnosis region, no unnecessary medium is interposed between the region of interest and the transducer 70, and the attenuation of the ultrasound waves is reduced. Ultrasound diagnosis can be done without any problems, and the sensitivity can be improved.

FIG. 11 is a diagram showing an example in which a probe position detection means is provided. In this example, the ultrasonic transducer 70 built into the probe tip 41 is fixed. A first magnetized pattern 131 and a second magnetized pattern 132 are formed on the outer cylinder of the probe 40 in an area approximately equal to the scanning range of the vibrator 70 . The first magnetized pattern 131 has S poles and N poles alternately magnetized at a pitch corresponding to a predetermined division angle in the longitudinal direction of the probe 40 . Further, the second magnetization pattern 132 has S poles and N poles alternately magnetized at a predetermined pitch in the radial direction of the probe 40. A forceps channel 50 of the endoscope tip 7, which has first and second channels.
At positions facing the magnetized patterns 131 and 132, magnetic sensors 133 and 134 made of, for example, magnetoresistive elements are attached to detect each magnetized pattern. Further, the probe 40 performs two independent operations of sliding and rotation by a drive mechanism provided in its scanning drive section (not shown). For this purpose, first and second magnetized patterns 131.
The longitudinal widths of 132 are set to equal lengths.

In this way, when the probe 40 is slid in the longitudinal direction, the position of the vibrator 70 at that time can be detected from the magnetized pattern 132 and the magnetic sensor 134. Also,
When the probe 40 is rotated, the S-pole and N-pole magnetic patterns that can detect the rotation angle of the vibrator 70 from the magnet pattern 131 and the magnetic sensor 133 move relative to the magnetic sensors 133 and 134. , S
Magnetic changes that are repeated alternately between poles and north poles can be detected as changes in electrical resistance, and can also be more compatible with digital processing. In addition, the magnetization pattern 13
1.132 and the magnetic sensor 133.134 may have an opposite positional relationship.

With this configuration, it is possible to accurately detect one rotation angle of the position of the vibrator 70.

Further, by performing radial scanning simultaneously with linear scanning, a three-dimensional ultrasonic diagnostic image can be obtained.

FIG. 12 is a diagram showing an example in which the ultrasonic transducer can transmit waves in the longitudinal direction and in front of the probe. An ultrasonic transducer 70 is provided at the probe tip 41 at an angle that transmits waves forward. In addition, two bimorphs 1 are placed at mutually opposing positions on the outer cylinder slightly protruding from the channel 50 of the endoscope tip 7 of the probe 40.
41°142 is attached. These two bimorphs 141 and 142 are connected to a power source via lead wires 143 and 144. By selectively energizing the bimorphs 141 and 142 through the lead wires 143 and 144, the probe tip 41 is bent. Further, the base end portion of the probe 40 is connected to a drive shaft that provides rotational movement in a scanning drive section.

With this configuration, when the bimorphs 141 and 142 are energized to periodically bend the probe tip 41, a convex scan can be performed in front of the probe 40. In addition, by adding rotational motion at the same time, 3
It is possible to obtain dimensional ultrasound tomographic images.

FIG. 13 is a diagram showing an example in which an electronic linear array is provided at the tip of the probe. As shown in the figure, an electronic linear array ultrasonic transducer 150 is provided at the probe tip 41,
A sector scan is performed, and the probe 40 itself moves in the longitudinal direction of the probe. Further, as shown in FIG. 14, an electronic convex array vibrator 151 is used. By doing so, a combined scan of sector scan and linear scan or convex scan and linear scan becomes possible, and the field of view width can be expanded.

FIG. 15 is a diagram showing an example in which at least two or more ultrasonic transducers are disposed at the tip of a probe inserted into an endoscope forceps channel. Each vibrator 70a.

The wave transmitting and receiving directions 70b are the same, and they are arranged at intervals calculated by dividing a predetermined scanning range by the number of vibrators. However, the distance between adjacent vibrators 70a and 70b is set to such a distance that their transmitted and received waves do not interfere with each other.

By providing multiple transducers in this way and assigning each transducer to each scanning range, it is possible to transmit and receive multiple transducers simultaneously, reducing the time required to obtain ultrasound diagnostic images of the entire scanning range. This enables high-speed scanning.

FIG. 16 is a diagram showing an example in which a plurality of vibrators are arranged close to each other at the tip of the probe. As shown in the figure, ultrasonic transducers 70a and 70b are arranged close to each other at a distance that does not interfere with each other's transmitted and received waves.

Vibrator 70a.

With the probe 70b arranged in this manner, the probe 40 is moved in the longitudinal direction. At this time, the two vibrators 70a, 7
Ultrasonic waves are transmitted and received simultaneously at 0b. Then, the overlapping range of the scanning range of the transducer 70a and the scanning range of the transducer 70b is defined as the entire scanning range, and the two ultrasonic images are aligned and added.

By doing this, the S/N ratio is improved by f7 times compared to an image signal obtained by moving one transducer over the entire scanning range. By increasing the number of transducers, images of the same part can be obtained by the total number of transducers, and the image obtained by adding them together is S
/N ratio is improved by f/rN71 times. Note that the required scanning time for the entire scanning range is not much different from that for a single vibrator.

FIG. 17 is a diagram showing an example in which a plurality of vibrators having different resonance frequencies are provided at the tip of the probe. As shown in the figure, each vibrator 70a, 70b has a different resonance frequency.
, 70c are arranged close to the probe tip 41, even if the transmitted and received waves of each of the vibrators 70a to 70c interfere, they can be easily separated.

Furthermore, the signal obtained by superimposing the ultrasonic signals at the same part of the transducers 70a to 70c having different resonance frequencies has a band that is the sum of the resonance bands of each of the transducers 70a to 70c, which is an extremely wide band. can generate a signal with If this broadband signal is used in a diagnostic device applying the pulse compression method, a high-resolution, high-sensitivity ultrasonic tomographic image can be obtained.

FIG. 18 is a block diagram showing the configuration of a circuit for synthesizing received signals from vibrators 70a to 70c with different bands and generating a wideband signal. The received signals output from each of the transducers 70a to 70c are input to the quadrature detection means 160, where they are band-converted and converted into low-frequency signals. This low-frequency signal is a complex signal containing phase information, and is divided into a real component and an imaginary component. Regarding the real component, in order for the transducers 70a to 70c to obtain reflected signals from the same location as received signals, it is necessary to cause a time delay according to the moving speed of the probe 40. Therefore, this time delay is delayed by one scanning delay using a delay line. In other words, the received signal of the transducer 70b is delayed by one scanning delay with respect to the transducer 70a, and the received signal of the transducer 70c is delayed by one scanning delay with respect to the transducer 70a.
It is obtained with a delay of two scanning delays with respect to the received signal of 0a.

By combining these signals in an adder 161, signals received at the same site by the transducers 70a to 70c having different bands are obtained. This composite signal is generated by three oscillators 70a to 70.
It is a composite of the bands of c. Combining is performed in the same manner for the imaginary components. The composite signal synthesized in this manner is output from the orthogonal modulation means 162 as a wideband signal.

FIG. 19 is a diagram showing an example in which a wave transmitting vibrator and a wave receiving vibrator are provided at the tip of the probe. As shown in the figure,
The probe tip 41 is provided with wave transmitting transducers 170 to 174 and wave receiving transducers 175 to 179. Oscillators 170 and 175 have the same focal range, and similarly, oscillator 1
71 and 178.172 and 177.173 and 176°17
4 and 175 have the same focal range, and are arranged so that their respective focal ranges coincide in each combination and are located on the center line of the vibrators 174 and 175.

The reflected wave of the ultrasound transmitted from the transducer 170 is received by the transducer 179, and the reflected wave of the ultrasound transmitted from the transducer 171 is then received by the transducer 178. Waves are transmitted and received in sequence. Here, the vibrator 17
Focusing on 0 and 179, since the distance ab between both oscillators is known in advance, the wave transmitted from point a is reflected at point b, and 0
The time required to reach the point is measured from the time of the pulse transmitted by the transducer 170 and the signal at the peak point of the signal received by the transducer 179, that is, the time of receiving the reflected wave in the focal region. can do. Also, the propagation distance a of the sound wave
bc can also be determined by simple geometric calculations. Similarly,
The propagation distance def and its propagation time can also be determined.

Also, the foot of the perpendicular line drawn from the aperture center d of the vibrator 171 to the line segment ab is defined as i, and the leg of the perpendicular line drawn from the aperture center f of the vibrator 178 to the line segment b is
If the foot of the vertical line drawn at c is j, line segments at and cj can be determined by simple geometric calculation from the installation positions of vibrators 170.171 and 178.179.

Since the sound speed of the acoustic medium near these vibrators is known, the time required to propagate along the line segments ai and cj can be determined.

Therefore, by subtracting the propagation time of def from the propagation time of the acoustic path ibj, the propagation time in gbh can be obtained, and at the same time, since the propagation distance gbh is also known, the propagation velocity in gbh can also be obtained. As a result, the speed of sound in the local region gbh of interest can be determined. Similarly,
The speed of sound in a local area can also be determined using other oscillators.

In this way, by measuring the sound velocity in a local area while moving the probe tip 41 in its longitudinal direction,
The speed of sound in a living body in a region corresponding to the range of movement can be determined, and biological tissue diagnosis can be performed using the speed of sound. Note that the method for determining the sound speed described above is based on the crossed beam method.

FIG. 20 is a diagram showing an example in which an overload prevention mechanism is provided by connecting the base end of the probe to the drive shaft of the scanning drive unit via a magnet. An ultrasonic transducer 70 is provided at the probe tip 41 .

Then, the proximal end 42 of the probe 40, which functions as a driving force transmission means, is connected to the drive source transmission shaft 180 in the scanning drive section.
are connected via permanent magnets 181 and 182. One of the permanent magnets 181 and 182 is an S pole, and the other is an N pole.
It is extreme. The drive source transmission shaft 180 has a degree of freedom in the sliding direction of the probe, and is a mechanism for sliding the probe in the longitudinal direction.

With this configuration, even if the probe tip 41 accidentally comes into contact with the intracorporeal wall, the connection is released when the load applied to the connection section exceeds the connection magnetic force of the permanent magnets 181 and 182.

Therefore, by controlling the magnetic force of the magnets 181 and 182, the load applied to the probe 40 can be adjusted, and inconveniences such as damage to the body cavity wall due to overload can be reliably avoided.

Note that in the above example, it is desirable to use a perspective view in order to make the diagnostic region of the endoscope and the region shown by the ultrasound image obtained from the ultrasound transducer common.

In this way, after confirming the body cavity wall surface image using the endoscopic image, the deep part of the corresponding surface region can be diagnosed using the ultrasound image, and effective information can be obtained.

FIG. 21 is a diagram showing an example in which the above-mentioned overload prevention mechanism is provided at the tip of the probe. The probe tip 41 is the tip member 4
It is divided into two members: a transmission member 1a, and a transmission member 41b that transmits driving force to the tip member 41a. Tip member 4
1a has a built-in vibrator 70, and this tip member 4
Transmission member 4 having an outer diameter slightly smaller than the inner diameter of 1a
One end of 1b is connected to the tip member 4 via magnets 191 and 192.
It is fitted into the opening of 1a. In addition, the magnet 191,
192, for example, the S pole is attached to the inner periphery of the tip member 41a, and the N pole is attached to the outer periphery of the insertion portion of the transmission member 41b.

By doing so, the driving force from the transmission member 41b is transferred to the tip member 41a through the magnetic force of the magnets 191 and 192.
If a load exceeding the specified value is applied,
The connection by magnets 191 and 192 is released and operates as a safety mechanism.

〔Effect of the invention〕

According to the present invention, an ultrasonic transducer is provided at the tip of the flexible probe, and a guide member for regulating the movement of the probe is provided at the tip of the endoscope, so that continuous scanning can be performed from linear scanning to convex scanning. This can be done in a number of ways, and the field of vision can be greatly expanded without causing any damage to the living body.

In addition, since the driving force for moving the ultrasonic transducer is transmitted through the driving force transmission means provided in communication with the probe, for example, a piston, a cylinder, and a laminated piezoelectric actuator for moving the piston can be used as the driving means. By using a transmission pipe or the like as a driving force transmission means, the scanning drive unit can be made smaller and lighter.

[Brief explanation of the drawing]

1 to 21 are diagrams showing embodiments of the present invention, FIG. 1 is a diagram showing a schematic configuration of an endoscopic ultrasonic diagnostic device, and FIG. 2 is a diagram showing a scanning drive unit attached to a connecting member. Figure 3 is a cross-sectional view of the tip of the endoscope, Figure 4 is a cross-sectional view of the tip of the probe, Figure 5 is a block diagram showing the configuration of the transmitter/receiver, and Figure 6 is the arc-shaped 7 is a diagram showing the probe guide shown in FIG. 6 as seen from the insertion side and its cross section. FIG. 8 is a diagram showing the end part of the endoscope equipped with a probe guide. Figures 9(a) and 9(b) are cross-sectional views of the tip of the probe equipped with a shape memory alloy, and Figures 10(a) and 10(b) are shown with a suction cup installed. FIG. 11 is a side view of the probe tip provided with a position detection means; FIG. 12 is a side sectional view of the probe tip with a pair of bimorphs attached; Figure 13 is a side view of the probe tip with an electronic linear array at its tip; Figure 14 is a side view of the probe tip;
The figure shows a side view of the probe tip with an electronic convex array at its tip, Figures 15 to 17 are side views of the probe tip with multiple oscillators, and Figure 18 shows a probe tip with an electronic convex array installed at the tip. Figure 19 is a side view of the tip of the probe with the transmitting and receiving transducers installed;
FIG. 20 is a diagram showing a state in which an overload prevention mechanism is provided at the base end of the probe, and FIG. 21 is a diagram showing a state in which an overload prevention mechanism is provided at the tip end of the probe. DESCRIPTION OF SYMBOLS 1... Endoscope, 7... Endoscope tip, 10... Ultrasonic diagnostic device, 12... Scanning drive part, 32... Cylinder, 33... Piston, 34...・Laminated piezoelectric actuator, 40... Probe, 50... Channel, 60... Transmission shaft, 70... Ultrasonic vibrator, 92.
...Probe guide.

Claims (6)

[Claims] (1) A channel provided in communication with the flexible part of the endoscope, a flexible probe that can be inserted into this channel, and an ultrasonic vibration provided at the insertion side tip of this probe. An endoscopic ultrasonic diagnostic apparatus comprising: a guide member connected to the channel and provided at the distal end of the endoscope to restrict movement of the probe. (2) An endoscopic ultrasound diagnostic apparatus, wherein the guide member according to claim 1 has an arc shape. (3) a flexible probe that can be inserted into a channel of an endoscope; an ultrasonic transducer that is movable along the longitudinal direction of the probe at the insertion-side distal end of the probe;
It consists of a driving means for moving the ultrasonic transducer in the longitudinal direction within the probe, and a driving force transmitting means provided in communication within the probe so as to connect the driving means and the ultrasonic transducer. An endoscopic ultrasound diagnostic device characterized by: (4) The driving means according to claim 3 includes a piston, a cylinder, and a piezoelectric actuator for moving the piston, and the driving force transmission means is a transmission whose both ends are connected to the cylinder and the ultrasonic vibrator, respectively. An endoscopic ultrasound diagnostic device comprising a tube and a fluid sealed within the transmission tube. (5) Any one of claims 1 to 4, characterized in that at least one of the channel of the endoscope or the probe is provided with detection means for detecting the position and/or direction of the ultrasonic transducer. The endoscopic ultrasonic diagnostic device described in one of the above. (6) The probe according to any one of claims 1 to 4, characterized in that a plurality of ultrasonic transducers each capable of independently transmitting and receiving ultrasonic waves are provided at the insertion-side distal end of the probe. Visual ultrasound diagnostic equipment.