JP4785102B2 - Ultrasonic probe for body cavity, manufacturing method thereof, and ultrasonic diagnostic system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, in-vivo (transesophageal, rectal, etc.) is inserted into ultrasonic inspection and a suitable body cavity ultrasonic probe in the ultrasonic endoscope for performing a biopsy (hereinafter ultrasonic feeler And the manufacturing method thereof and an ultrasonic diagnostic system .
[0002]
[Prior art]
Ultrasound endoscopes that perform ultrasound examination and biopsy of tumors in the esophagus and the like are widely used. Ultrasound endoscopes are provided with an ultrasound probe at the tip of an endoscope tube. Endoscopy for examining the position, size, color, and aspect of an affected area from the internal surface of an organ, In addition to being able to perform both cross-sectional image inspection of the affected area brought about by the acoustic probe, it is possible to excise the affected area with forceps attached to the endoscope.
[0003]
Ultrasonic probes provided in an ultrasonic endoscope are roughly classified into a mechanical scanning type and an electronic scanning type. In the mechanical scanning type, for example, a motor is arranged in the operation section of the endoscope, and an ultrasonic transducer rotatably provided via a bearing at the distal end of the tube of the endoscope is rotated or oscillated by the driving force of the motor. It is supposed to let you. In the electronic scanning type, an array transducer is provided at the tip of the endoscope tube.
As an array transducer type of the electronic scanning ultrasonic probe, a linear array type, a convex array type, or the like is used.
[0004]
The ultrasonic vibrator has a plurality of matching layers on the front face of the piezoelectric vibrator and an acoustic lens dedicated to ultrasonic waves in the minor axis direction of the array vibrator, and the back face of the piezoelectric vibrator toward the back face of the vibrator. absorbing the emitted ultrasound, it has a back key ring material for attenuating.
[0005]
By the way, as described above, the ultrasonic endoscope is required to have a function as an endoscope and a tissue excision / collection function for biopsy in addition to the ultrasonic probe. For this reason, a lens, a mirror, an optical fiber, a light guide, forceps, an operation wire thereof, and the like are arranged in the tube of the endoscope.
[0006]
Therefore, it is necessary to secure a space for arranging them. However, in the structure of the conventional vibrator, the thickness of the vibrator becomes an obstacle, and the type of vibrator used in the ultrasonic endoscope is the type described above. It was limited to.
[0007]
An object of the present invention is to provide an ultrasonic endoscope probe capable of electronically scanning a so-called radial scan in which an ultrasonic transducer is mechanically rotated to scan an ultrasonic wave in the entire circumferential direction. To do.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention inserts a strip-shaped piezoelectric vibrator arranged, a backing material having a predetermined hardness placed on the opposite side of the ultrasonic wave transmission surface from the piezoelectric vibrator, and a treatment instrument. An electronic scanning ultrasonic probe for body cavities, the material being harder than the backing material between the piezoelectric vibrator and the backing material, the hollow space It is characterized by the provision of an intervening layer for expanding the width .
[0009]
The hollow space has a structure in which 50% or more of the array surface curvature radius of the piezoelectric vibrator is provided in the electronic scanning ultrasonic probe having a curvature radius of 15 mm or less .
[0010]
Further, the ultrasonic probe for body cavity is provided with means for moving the strip-shaped piezoelectric transducer array arranged in a circular shape in the insertion / extraction direction .
[0011]
A body cavity ultrasound probe comprising means for detecting the position of the body cavity ultrasound probe in a hollow space in the axial center of the body cavity ultrasound probe insertion / extraction direction; The image processing apparatus includes means for synthesizing ultrasonic images picked up at each position based on the position detection information and rendering a three-dimensional stereoscopic image .
[0012]
A step of adhering an intermediate layer (5) harder than the first backing material (6) to the sheet-like first backing material (6); a piezoelectric vibrator (1); 1 acoustic matching layer (2) and 2nd acoustic matching layer (3) are adhere | attached, a piezoelectric vibrator (1), 1st acoustic matching layer (2), 2nd acoustic matching layer (3), and intervening layer (5) And cutting the first backing material (6) to form an array vibrator, and bonding the array vibrator to the outer periphery of the hollow backing material (7). And a method of manufacturing an intracavity ultrasonic probe, comprising: adhering an acoustic lens (4) to the outer periphery of the first acoustic matching layer (2) .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an overall view of an ultrasonic endoscope. In FIG. 1, reference numeral 100 denotes a distal end portion which is a characteristic part of the present invention, 28 is a bending portion that is bent by a bending operation knob 32, 29 is a soft portion that bends softly, and 30 is sequentially connected to a base end of the soft portion 29. The sub-operation unit 31 is a main operation unit that controls the tip 1, 32 is a bending operation knob that performs a bending operation of the bending unit 28, and 33 is an eyepiece part of an operator who observes an endoscope. An eyepiece unit 34 is connected to a nibble (not shown), an aspiration device is connected to the nibble, and an aspirating operation unit 35 for aspirating unnecessary liquid accumulated in the subject by hand operation. An air / water supply switching operation unit for jetting water, 38 is a long tubular light guide cable unit for propagating light, 39 is an electric cable, 40 is a connector for connecting to a light source device (not shown), 41 is a power supply (not shown) Connector for connecting to, 42 are connected port.
[0014]
FIG. 2 shows a cross section of the tip 1. In FIG. 2, 8 is a CCD element for imaging the inside of a body cavity, 9 is a CCD cable, 10 is an optical fiber or a light guide, and 11 is a space for inserting a treatment instrument such as forceps. The distal end portion 1 is provided with a holding member 12 for storing, holding, and positioning the piezoelectric vibrator elements. Next, the structure of the arrayed vibrator, which is a characteristic part of the present invention, will be described.
[0015]
FIG. 3 is an enlarged view showing the structure of the array transducer. In FIG. 3, 4 is an acoustic lens for forming a focal point at a predetermined distance from the transducer surface in order to make the ultrasonic beam as thin as possible in the direction orthogonal to the direction of arrangement of the transducers, and 2 and 3 are piezoelectric transducers. A first acoustic matching layer and a second acoustic matching layer for matching the acoustic impedance between 1 and the subject, 1 is a piezoelectric vibrator that generates an ultrasonic wave using a piezoelectric phenomenon, and 5 is described later. The intervening layers 6 and 7 which are characteristic portions of the present invention are a first backing material and a second backing material for reducing the intensity of ultrasonic waves radiated from the piezoelectric vibrator 4 to the back surface.
[0016]
As a material of the intervening layer 5 provided between the piezoelectric vibrator 4 and the inside 6 of the backing, for example, a material made of a material harder than the backing material such as epoxy resin or urethane resin is used. As a result, the thickness of the soft backing material can be reduced, and its hard property increases the stability when dicing the vibrator, thereby preventing the element from collapsing and the accompanying pitch deviation of the piezoelectric vibrator. As a result, it is possible to reduce the thickness of the backing material that has been conventionally required to increase the stability. Specifically, in a small convex scanning ultrasonic probe with a curvature radius of 15 mm or less, 50% or more of the curvature radius of the piezoelectric transducer array surface can be secured as a hollow space.
[0017]
Further, the acoustic impedance of the intervening layer 5 was made smaller than that of the backing material. As a result, there is an advantage that the rate of reflection of ultrasonic waves at the interface with the piezoelectric vibrator is further increased.
[0018]
In addition, the thickness of the intervening layer 5 was formed to be n times (n is an integer) about ¼ wavelength of the probe center frequency. As a result, after the ultrasonic wave generated from the back surface of the vibrator, that is, the backing material side of the vibrator is reflected at the boundary portion between the intervening layer and the backing material, it is an integral multiple of about 1/2 wavelength of the ultrasonic wave. It returns to the vibrator as a reflected wave having a phase difference. That is, for example, if the value of n is 2, at the time of wave transmission, the ultrasonic wave generated by the vibrator itself and the reflected wave reflected by the intervening layer can be synchronized.
[0019]
Similarly, at the time of wave reception, the ultrasonic wave reflected by the subject is converted into an electric signal by the piezoelectric vibrator and propagated to the intervening layer. Here, most of the ultrasonic wave propagated to the intervening layer is propagated to the backing material, but a part of the ultrasonic wave is propagated (reflected) to the vibrator and converted into an electric signal. Therefore, an ultrasonic waveform that has a small attenuation corresponding to the addition of the reflected wave to the ultrasonic wave directly propagated to the piezoelectric vibrator and that has a long duration by the phase difference generated in the reflected wave, that is, an ultrasonic waveform that has a long duration is electrically generated. It will be converted into a signal.
[0020]
That is, at the time of wave transmission and wave reception, in addition to the ultrasonic wave generated by the vibrator itself or converted into an electrical signal by the vibrator, an ultrasonic wave reflected between the intervening layer and the backing material is added. The attenuation of the ultrasonic wave is small or the duration of the ultrasonic waveform is long. The longer the wave duration, the narrower the peak width when converted to the frequency spectrum, making it easier to see the frequency shift caused by the blood flow speed when performing Doppler measurement, and the blood flow image is more accurate than before. Can be obtained. As a result, an ultrasonic device suitable for measuring a blood flow velocity and obtaining a blood flow velocity image based on the blood flow velocity while preventing deterioration of the image quality of the ultrasonic image due to a deterioration in the function of the backing material is provided. Will be able to.
[0021]
Further, if 50% or more of the hollow space can be secured, various probes utilizing the characteristics can be obtained. Next, second and third embodiments using this will be illustrated with reference to FIGS. FIG. 4 is an explanatory diagram of an embodiment in which a position detection sensor is mounted on an ultrasonic probe. In FIG. 4, 13 is a small position detection sensor, and 14 is a position detection sensor cable. As a sensor for position detection, a magnetic sensor that converts a displacement of a magnetic field into an electric signal and an inertial sensor (an acceleration sensor, a gyro sensor, etc.) that converts an amount of change in inertial force into an electric signal can be considered. As a result, the position of the probe can be detected, so that a three-dimensional ultrasonic image can be obtained based on the image and position information at each position.
[0022]
FIG. 5 is an explanatory diagram of a mechanism for moving the ultrasonic transmission / reception unit of the probe in the insertion direction. In FIG. 5, 15 is a shaft for mechanically moving an ultrasonic transmission / reception unit opened in a hollow space in the probe insertion / removal direction, 16 is a rack formed at the base of the shaft 15, and 17 is a rack 16. , A pinion for moving the ultrasonic transmission / reception unit, 18 a motor for rotating the pinion 17 (for example, a stepping motor), 19 an acoustic propagation medium for improving acoustic transmission, and 20 for the acoustic propagation An acoustic window for preventing the medium 19 from leaking to the outside and efficiently sending sound waves forward, 21 is a housing tip of the body cavity probe, and 22 is filled with water in a balloon (not shown). A nozzle for filling water in the balloon, 24 a water injection port for injecting water, 25 an ultrasonic signal cable, and 26 a mode. Over which is a drive for the power cable. As a result, by alternately performing ultrasonic transmission / reception and movement of the array transducer by the stepping motor, a three-dimensional image can be created based on the tomographic image at each position, as in the case of FIG.
[0023]
As an example of the configuration of such an ultrasonic (endoscope) system, FIG. 6 has been proposed. Reference numeral 50 denotes a display monitor, 51 denotes an ultrasonic image processing apparatus, 52 denotes an ultrasonic observation apparatus, 53 denotes a three-dimensional scanning drive unit, and 54 denotes a three-dimensional ultrasonic probe.
[0024]
Although the three embodiments of the present invention have been described with reference to the drawings, the gist of the present invention is that an intervening layer harder than the backing material is provided between the piezoelectric vibrator and the backing material, whereby the backing material and the intervening layer are separated. Since the combined thickness can be reduced, a hollow space is provided at the center of the probe axis, and an endoscope or the like is provided there. However, the present invention is not limited to the above embodiment.
[0025]
Finally, a manufacturing method is explained in full detail about the ultrasonic probe of the said Example. In order to realize a convex scanning electronic scanning ultrasonic probe having a curved surface of a piezoelectric vibrator having a curvature radius of 15 mm or less by cutting the piezoelectric vibrator into a strip shape,
(1) The intervening layer 5 is bonded to the sheet-like first backing material 6. The first backing material 6 is made of, for example, a rubber-like or film-like substance in order to curve the piezoelectric vibrator. The intervening layer 5 is made of, for example, an epoxy-based or urethane-based resin having a higher hardness than that of the first backing material 6. In this embodiment, the intervening layer 5 is preferably formed of a material such as an epoxy-based or urethane-based resin or polymethylpentene, but is not limited to this, and any material having a higher hardness than the first backing material 6 can be used. Needless to say, other materials may be used.
(2) The piezoelectric vibrator 1 and the first and second acoustic matching layers 2 and 3 are adhered to the intervening layer 5 of (1), and the piezoelectric vibrator 1, the first and second acoustic matching layers 2 and 3 and the intervening layer 5 are bonded. Layer 5 is cut into strips. The backing material 6 is cut as necessary.
(3) The arrayed vibrator manufactured in (2) is bonded to the outer periphery of the hollow backing material 7.
(4) Finally, the acoustic lens 4 is bonded. In the present embodiment, description of the signal transmission means for applying an electric signal to the piezoelectric vibrator is omitted.
[0026]
【The invention's effect】
As described above, according to the present invention, an ultrasonic transducer for an ultrasonic endoscope for inserting into a body cavity (transesophageal, transrectal, etc.) and performing ultrasonic examination and biopsy is provided. The so-called radial scan, in which the ultrasonic wave is scanned in the entire circumferential direction by mechanically rotating the lens, can be electronically scanned.
[Brief description of the drawings]
FIG. 1 is an overall view of an ultrasonic endoscope.
FIG. 2 is a view showing the tip of the ultrasonic probe of the present invention.
FIG. 3 is an enlarged view showing the structure of a piezoelectric vibrator array.
FIG. 4 is a diagram showing a probe tip portion of a second embodiment of the present invention on which a position detection sensor is mounted.
FIG. 5 is a cross-sectional view of a probe according to a third embodiment of the present invention provided with a mechanism for moving an ultrasonic transmission / reception unit in the insertion direction.
FIG. 6 is a block diagram showing a configuration example of an ultrasound (endoscope) system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Piezoelectric vibrator 5 ... Intervening layers 6, 7 ... Backing material

Claims (5)

A strip-shaped piezoelectric vibrator arranged, a backing material having a predetermined hardness disposed on the opposite side of the ultrasonic wave transmission surface from the piezoelectric vibrator, and a hollow space provided for inserting a treatment instrument. An electronic scanning ultrasonic probe for body cavity, wherein an intervening layer is provided between the piezoelectric vibrator and a backing material, which is harder than the backing material and expands the hollow space. A characteristic ultrasonic probe for body cavity.   2. The body cavity superstructure according to claim 1, wherein the hollow space has a structure in which 50% or more of an array surface curvature radius of the piezoelectric vibrator is provided in the electronic scanning ultrasonic probe having a curvature radius of 15 mm or less. Sonic probe. The means for moving the strip-shaped piezoelectric transducer array arranged in a circle in the insertion / extraction direction is provided in the ultrasonic probe for body cavity. Intracavity ultrasound probe. The means for detecting the position of the ultrasonic probe for body cavities is provided in the hollow space of the axial center of the ultrasonic probe insertion / extraction direction for the body cavities according to any one of claims 1 to 3. An ultrasonic wave comprising: the ultrasonic probe for body cavity described above; and means for rendering a three-dimensional stereoscopic image by synthesizing an ultrasonic image captured at each position based on the position detection information Diagnostic system. The step of adhering the intervening layer (5) harder than the first backing material (6) to the sheet-like first backing material (6), the piezoelectric vibrator (1), the first acoustic wave on the intervening layer (5) The matching layer (2) and the second acoustic matching layer (3) are bonded, and the piezoelectric vibrator (1), the first acoustic matching layer (2), the second acoustic matching layer (3), and the intervening layer (5) are strips. Cutting the first backing material (6) and forming an array vibrator, bonding the array vibrator to the outer periphery of the hollow backing material (7), Bonding the acoustic lens (4) to the outer periphery of the first acoustic matching layer (2), and a method for producing an intracavity ultrasonic probe.

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