JP2658689B2 - Ultrasonic probe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe which is inserted into a body cavity of a human body or the like and inspects a state of a body tissue by receiving an ultrasonic transmission signal.

[0002]

2. Description of the Related Art As an ultrasonic inspection apparatus, one that transmits and receives an ultrasonic signal from a body skin to a body is used. In recent years, in order to enable more accurate inspection, A device that is inserted into a body and configured to transmit and receive an ultrasonic signal from an inner wall of a body cavity directly to a site to be inspected has been used. Here, an ultrasonic inspection apparatus of a body insertion type generally includes an ultrasonic probe in which an operation section for grasping and operating by an operator is provided with an insertion section inserted into a body cavity, and an ultrasonic probe. The ultrasonic observation apparatus generally includes a transmission / reception circuit, a signal processing circuit for a received signal, and a monitor for displaying an ultrasonic image.

[0003] Most of the insertion portion of the ultrasonic probe is formed of a flexible portion that bends freely along the insertion path, and a distal end hard portion to which an ultrasonic vibrator is attached is continuously provided at the distal end of the flexible portion. ing. In some cases, an angle portion is provided between a soft portion and a distal end hard portion in the insertion portion.
This angle part has a node ring structure, and by pushing and pulling the operation wire inserted through this angle part,
The configuration is such that the distal end hard portion on which the ultrasonic vibrator is mounted is directed in a desired direction. Here, the angle portion is required to be provided when the ultrasonic probe itself is inserted into the body or the like by itself, but the distal end hard portion is extended to a portion where a predetermined ultrasonic inspection is performed by a guide means such as an endoscope. When the angle can be guided, there is no need to provide an angle portion.

[0004] Thus, the insertion portion of the ultrasonic probe is guided to a position where a predetermined ultrasonic observation is performed in the body, and the ultrasonic transducer is operated based on a signal from the ultrasonic transmission / reception circuit, and is inserted into the body. An ultrasonic pulse is directed toward the apparatus, the reflected echo is received, the received signal is subjected to predetermined signal processing in a signal processing circuit, and an ultrasonic image is displayed on a monitor. In this way, the state of the tissue cells in the body is inspected, but in order to increase the transmission and reception impedance of the ultrasonic wave and improve the transmission and reception efficiency, a coil is provided in parallel with the ultrasonic vibrator and the ultrasonic wave is provided. The resonance frequency is set to be equal to the limiting capacity of the vibrator, but this coil is usually provided with a relay board in the operation section from the viewpoint of downsizing of the insertion section, and is mounted on the relay board. I was

[0005]

By the way, a coaxial cable, for example, is interposed between the ultrasonic transducer and the relay board, and this coaxial cable has a distributed capacitance. Therefore, since the resonance characteristics of the coil are naturally affected by the distributed capacitance of the coaxial cable, the number of turns of the coil must be set in consideration of the distributed capacitance, and circuit design becomes difficult. Along with
Inconveniences such as not being able to obtain sufficient stability in the resonance characteristics occur. As a result, there is a drawback that a desired transmission / reception impedance cannot be obtained, transmission / reception efficiency is reduced, and S / N is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks and problems of the prior art, and aims at disposing a coil at a position which is not affected by the distributed capacitance of a coaxial cable. It is.

[0007]

In order to achieve this object, the present invention provides an insertion part inserted into a body cavity or the like, a flexible part made of a flexible member having at least a cable inserted therein, and an ultrasonic wave. A coil connected to the cable near the tip of the soft part, and connecting the wires connected to both electrodes of the ultrasonic transducer to the coil. It is characterized by having a configuration.

[0008]

The effect of the distributed capacitance of the coaxial cable is eliminated by providing the coil close to the ultrasonic vibrator. Here, the position closest to the disposition position of the ultrasonic transducer is the distal end hard portion in the insertion portion. However, the rigid tip portion must not be thickened due to its properties. This means that, even if the ultrasonic probe is of a type inserted into a body cavity by itself, a type of ultrasound probe inserted into a body cavity or the like using a guide means such as a treatment tool insertion channel of an endoscope is used. In any case, reducing the diameter of the insertion portion is an essential requirement.
Although not as important as the reduction in diameter, even if the distal end hard portion is elongated in the axial direction, a problem still occurs in the insertion operability.

[0009] Now, when an examination method using an ultrasonic probe is considered, a typical example is an A mode,
There are methods for acquiring M-mode and B-mode images. Of the ultrasonic image acquisition methods in these various modes, a single-plate ultrasonic transducer may be provided to acquire the A-mode and M-mode ultrasonic images. Further, even when a B-mode image is obtained, a single-plate vibrator is used in the case of mechanical scanning. However, in the case of acquiring a B-mode ultrasonic image, in the electronic scanning method, it is necessary to provide a large number of transducers side by side, and only in this case, a plurality of coils are provided because a plurality of ultrasonic transducers are arranged. Alternatively, an electronic switch must be provided between the coil and the ultrasonic transducer.

As described above, in the case of the ultrasonic probe of the type operating in each of the A mode, the M mode and the B mode of the mechanical scanning using the single-plate vibrator, one coil may be provided. Therefore, depending on the arrangement, it is possible to dispose the coil at a position near the ultrasonic transducer without increasing the diameter of the insertion portion. Here, an ultrasonic transducer is mounted on the distal end hard portion of the insertion portion of the ultrasonic probe, and this ultrasonic transducer has a certain surface area in order to increase the power of the ultrasonic beam emitted therefrom. This ultrasonic vibrator is mounted because an acoustic lens for focusing the ultrasonic beam is mounted on the transmitting and receiving surface side of the ultrasonic wave, and a backing member is mounted on the back side. The outer diameter of the hard tip portion to be used needs a certain size. On the other hand, a cable connected to the ultrasonic vibrator must be inserted into the inside of the flexible portion, but members other than the cable need not necessarily be inserted. In addition, in the case of a single-plate vibrator, only one coaxial cable needs to be inserted, so that the flexible portion has a considerable extra space. Even if the soft portion is made smaller than the diameter of the distal end hard portion, unless the diameter of the distal end hard portion is changed, the operability of insertion into the body cavity or the treatment instrument insertion channel of the endoscope is not necessarily improved.

Therefore, in the present invention, a configuration is adopted in which a coil is disposed in the flexible portion by utilizing an extra space in the flexible portion. That is, the wiring from the ultrasonic vibrator is guided to the inside of the flexible portion, and is connected to a coil disposed at a position near the distal end hard portion in the flexible portion. Then, the wiring from the coil is inserted into the coaxial cable and extends to the operation unit. As a result, the coil is arranged at a position very close to the ultrasonic vibrator, so that its resonance characteristics are stabilized, the transmission / reception impedance is increased, the transmission / reception efficiency is improved, and the S / N is improved.

Here, since the coil is a relatively small electronic component, the coil does not have a large diameter in the insertion portion because it can be sufficiently accommodated in the space in the flexible portion. In addition, although the coil arrangement portion is hard, the coil arrangement portion is located at a position apart from the distal end hard portion, the hard portion in the entire insertion portion is dispersed, and furthermore, it is necessary to provide this coil. The length of the hard part in the soft part caused by the above is extremely small. Therefore, even if the coil is provided in the flexible portion, the operability of inserting the insertion portion into the body cavity or the operability of inserting the endoscope into the treatment instrument insertion channel does not deteriorate.

Generally, when inserting the insertion portion of the ultrasonic probe (or the insertion portion of the endoscope itself when inserted through the treatment instrument insertion channel of the endoscope) into the body cavity, In order to direct the portion in a desired direction, an angle portion is continuously provided to the distal end hard portion, and the angle portion is bent at a sharp angle, for example, 180 ° or more. Therefore, it is preferable to dispose the coil at a position avoiding a portion that is bent at such a sharp angle from the viewpoint of operability of the angle operation and protection of the coil. That is, in the case of an ultrasonic probe of a type that is directly inserted into a body or the like, the ultrasonic probe is disposed at a position close to an angle portion of a flexible portion constituting the insertion portion. When the treatment instrument insertion channel of the endoscope is used as a guide, when the distal end of the ultrasonic probe is most protruded from the treatment instrument insertion channel, the base is positioned from the position of the angle portion in the insertion section on the endoscope side. What is necessary is just to arrange in the position of an end side.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, FIG. 1 shows a schematic configuration of an ultrasonic probe, and FIG. 2 shows a configuration of an insertion portion thereof. here,
The ultrasonic probe P shown in FIG. 1 is guided by being inserted through a treatment tool insertion channel C provided in an insertion portion I of an endoscope S, and has a rotatable distal end portion. It is.

As is apparent from FIG. 1, the ultrasonic probe P generally comprises an operating section 1, an insertion section 2, and a cable 3 connected to an ultrasonic observation apparatus (not shown). You. The insertion section 2 is provided with a connector 20 detachably connected to the operation section 1 on the base end side thereof, and a large portion from the base end side is a flexible section 21 made of a flexible tube. A distal end hard portion 22 is connected to the distal end of the flexible portion 21. A flat portion 22a is formed in the distal end hard portion 22 by cutting out an intermediate portion thereof, and the ultrasonic vibrator 4 made of a single plate is mounted on the flat portion 22a. An acoustic lens 5 is laminated on the ultrasonic transmitting / receiving surface side of the ultrasonic transducer 4, and a backing member 16 is mounted on the back surface side.

As shown in FIG. 3, the ultrasonic vibrator 4 is provided with a front electrode 4b on one side of a piezoelectric element 4a.
A back electrode 4c is provided on the opposite surface. The wiring 5 connected to these two electrodes 4b, 4c
Reference numerals a and 5b extend to the inside of the flexible portion 21 and are connected to the coil 6 for achieving the limited capacity of the ultrasonic vibrator 4 and the resonance frequency. The coil 6 is mounted in the flexible portion 21 and wires 7a and 7b from the coil 6 are provided.
Is inserted through the coaxial cable 8 inserted into the flexible section 21 and is routed from the operation section 1 to the cable 3 connected to the ultrasonic observation apparatus.

Here, the ultrasonic probe P is inserted into the body by using the treatment tool insertion channel C of the endoscope S as a guide. The insertion portion I of the endoscope S has a flexible portion F
And an angle portion A is connected to the treatment instrument insertion channel C.
The angled portion A is bent at a steep angle such as 180 ° or more in order to direct the distal end hard portion R provided with the opening in a desired direction. Therefore, when the coil 6 makes the insertion portion 2 of the ultrasonic probe P most protrude from the treatment tool insertion channel C, the insertion portion I of the endoscope S
At the base end side of the position of the angle portion A, ie, the flexible portion F
It is arranged in the position inside. In the drawing, reference numeral 9 denotes a sealing member for sealing the opening 22b for inserting the wiring of the distal end hard portion 22. In addition, the coil 6 is
In order to stably hold the inside of the
The arrangement of the coil 6 in the inside can be filled with the sealant 10.

The present embodiment is constructed as described above. As is apparent from FIG. 1, this ultrasonic probe P is provided with a predetermined internal body through the treatment instrument insertion channel C of the endoscope S. The ultrasonic inspection is performed by being guided to the position and transmitting and receiving the ultrasonic signal from the inner wall of the body cavity at the relevant site. That is, from a state in which the insertion section 2 is led out from the distal end of the endoscope S by a predetermined length, the insertion section 2 is displaced in a direction of being drawn into the endoscope S. For each moving distance, the light enters the body, and the reflected echo is received to perform mechanical linear scanning. This ultrasonic reception signal is transmitted to the ultrasonic observation device, and the ultrasonic reception device performs predetermined scanning. Is performed, and the ultrasonic image is displayed on the monitor screen.

Since the coil 6 is located relatively close to the ultrasonic vibrator 4 in the insertion section 2, the coil 6 is not affected by the distributed capacitance of the coaxial cable 8 and the resonance characteristics are extremely stable. It can be maintained in the state. Therefore, the transmission and reception impedance of the ultrasonic wave can be increased, the transmission and reception efficiency becomes extremely good, and the S / N can be improved.

Since the coil 6 is not provided on the hard tip portion 22, the hard tip portion 22 does not increase in size in the diameter direction or the axial direction. And
The coil 6 is bent at a sharp angle at the insertion portion I of the endoscope S even when the insertion portion 2 of the ultrasonic probe P is protruded to a state where the scanning is performed, that is, to the leading end position in the scanning stroke. Since the flexible portion F is located at the flexible portion F on the base end side from the position of the angle portion A, even if the flexible portion F is bent along the insertion path, it does not bend very sharply, which hinders the operability of the angle operation. And the coil 6 is not likely to be damaged. Moreover,
The coil 6 is a relatively small electronic component. From these,
When viewed from the entire insertion portion 2, the hard portion is only the portion where the coil 6 is disposed in the distal end hard portion 22 and the soft portion 21, and the hard portion is dispersed at two places.
The operability of insertion into the treatment instrument insertion channel C is not impaired.

In the above-described embodiment, the ultrasonic probe is configured to be inserted by using the treatment tool insertion channel of the endoscope as a guide. However, the insertion portion itself of the ultrasonic probe is directly inserted into the body. It can also be configured to be inserted into. In this case, it is necessary to interpose an angle portion between the soft portion and the distal end hard portion in the insertion portion, and to configure the angle portion to be able to bend in a desired direction by remote control, Also, the coil may be disposed near the portion connected to the angle portion in the flexible portion, avoiding the position of the angle portion.

[0022]

As described above, according to the present invention, since the coil is provided in the vicinity of the distal end of the flexible portion, the resonance characteristics can be maintained in a very stable state, and the transmission / reception impedance of the ultrasonic wave can be reduced. The transmission / reception efficiency can be extremely improved, the S / N ratio can be improved, and the insertion portion does not have a large diameter, and the hard portion is dispersed so as to be two small portions. So
There are various effects such as the operability of the insertion operation to the guide member such as the treatment tool insertion channel in the body cavity or the endoscope is not impaired.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view showing an ultrasonic probe together with an endoscope serving as a guide thereof.

FIG. 2 is an enlarged sectional view of a distal end hard portion of the ultrasonic probe.

FIG. 3 is an explanatory diagram illustrating a configuration of an ultrasonic transducer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Operation part 2 Insertion part 4 Ultrasonic vibrator 5a, 5b, 7a, 7b Wiring 6 Coil 8 Coaxial cable 21 Flexible part 22 Tip hard part 22a Flat part

 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-297460 (JP, A) JP-A-1-244739 (JP, A) JP-A-1-291844 (JP, A) 503279 (JP, A)

Claims (2)

(57) [Claims] An insertion portion to be inserted into a body cavity or the like comprises at least a soft portion made of a soft member having a cable inserted therein and a hard tip portion having an ultrasonic vibrator mounted thereon. An ultrasonic probe, wherein a coil connected to the cable is provided near the distal end of the ultrasonic probe, and wiring connected to both electrodes of the ultrasonic transducer is connected to the coil. 2. The structure according to claim 1, wherein an angle portion is provided between the flexible portion and the distal end hard portion in the insertion portion, and the coil is provided near a portion of the flexible portion connected to the angle portion. 2. The ultrasonic probe according to 1.