JPH0787836B2 - Ultrasonic coupler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ultrasonic coupler. More specifically, the present invention relates to an ultrasonic coupler that is interposed between an ultrasonic probe and a contact surface of a subject used in the field of biological measurement using ultrasonic waves.

(Prior Art) An ultrasonic diagnostic apparatus is used in many diagnostic fields including an abdominal organ such as a heart and a liver because of its simplicity and non-invasiveness to a patient.

For example, in patients with heart disease, in order to perform an open heart surgery accurately, it is desirable that the position and shape of the lesion site and the relationship with the normal part adjacent to the lesion site be diagnosed in detail before surgery, especially in neonates and the like. In the seriously ill case, the accuracy of preoperative diagnosis using an ultrasonic diagnostic apparatus is very important for improving the recent surgical results. However, preoperative ultrasonography cannot obtain sufficient information on a heart disease or a lesion while applying a probe from above the chest wall to avoid lungs and bone tissue. As a method of performing more detailed ultrasonic diagnosis beyond this limit, ultrasonic examination during an operation of interest can be considered. That is, if a probe is directly applied from the outside of the pericardium or the incision of the heart or blood vessel after the midline sternotomy to perform ultrasonic examination, a more detailed surgically useful diagnosis can be obtained for each lumen. In addition, it is possible to confirm intraoperatively whether or not the surgical procedure performed by the intraoperative ultrasonic examination was appropriate, which is important for prevention of reoperation and postoperative management.

In ultrasonic diagnosis, an ultrasonic pulse is radiated into the body from the surface of the body or the surface of an organ, and a reflected wave generated due to a difference in acoustic impedance between tissues in the body is received to obtain a tomographic image of the body. Therefore, in order to obtain an accurate tomographic image, it is necessary to bring the ultrasonic probe into close contact with the surface of the body or the surface of the organ without the presence of an air layer having a high reflectance for ultrasonic waves.

However, when the probe is directly applied to the body surface in this way, in the obtained image, the shape of the tissue such as the blood vessel near the body surface is obtained by being deformed by the pressure. Further, when an ultrasonic examination is performed by directly applying a probe to the heart or blood vessel wall, the heart and blood vessels move in a non-uniform manner along with the heartbeat, and when pressure is applied by the probe, an arrhythmia and a decrease in blood pressure are likely to occur. Therefore, it is difficult to keep a conventional probe having a non-deformable contact surface in close contact with the surface of the pulsating heart, etc., and to use it safely. In practice, the usefulness of intraoperative real-time ultrasonic tomography is sufficient. The reality is that it has not been demonstrated.

Therefore, in these cases, an appropriate contact medium substance for use between the probe and the surface of the body or the surface of the organ is required, that is, a soft contact medium that follows its movement while closely adhering to the surface of the heart or the like. There is a need for an ultrasonic coupler with excellent bulk and ultrasonic characteristics.

Conventionally, in this type of ultrasonic coupler, FIG.
And (B), the subject 2 of the elastic acoustic medium 1
The projecting portion 1a of the portion contacting with is projecting from the opening 4 on the subject side of the fixing member 3 with the same width as the opening width W, that is, with the same area as the opening area (JP-A-61-288). , 84
No. 0). The surface of the elastic acoustic medium 1 in contact with the ultrasonic wave transmitting / receiving surface 5a of the ultrasonic probe 5 had a flat shape. Further, the mounting means, the positioning means, and the like when mounting the ultrasonic coupler on the ultrasonic probe 5 have not been prepared yet, and the method for housing the elastic acoustic medium 1 in the fixing member 3 is not the same. It wasn't in place.

The shape of the ultrasonic coupler is shown in FIG.
As shown in (B) and (C), with respect to the cross-sectional shape of the elastic acoustic medium 1 orthogonal to the ultrasonic scanning direction, an example is known in which the width thereof becomes narrower in the ultrasonic wave transmitting direction. In Japanese Patent Laid-Open No. 63-36,173, the sectional shape parallel to the ultrasonic scanning direction and the ultrasonic wave transmitting direction is a rectangle or a shape in which the width becomes wider in the ultrasonic wave transmitting direction (Japanese Patent Laid-open No. Sho 63-36,173). 63-117,735). Further, conventionally, in this type of ultrasonic coupler, the elastic acoustic medium 1 is limited to the one that protrudes from the fixing member to the subject side.

(Problems to be Solved by the Invention) However, as in the conventional case, when the elastic acoustic medium is projected from the opening of the fixed member on the subject side by the same value as the opening width, it is shown in FIG. 4 (B). As described above, when the ultrasonic coupler is moved on the subject 2, the elastic acoustic body 1 is bent and the transmission / reception of desired ultrasonic waves is disturbed, resulting in image deterioration. Alternatively, there is a problem that the elastic acoustic medium 1 is damaged due to bending of the elastic acoustic medium 1. Further, since the surface of the elastic acoustic medium 1 that contacts the ultrasonic wave transmitting / receiving surface of the ultrasonic probe 5 is flat, when the ultrasonic coupler is bonded to the ultrasonic probe, the elastic acoustic medium 1 and the ultrasonic wave transmitting / receiving surface of the ultrasonic probe are elastic. There is a problem that bubbles (air) are mixed in the contact surface with the acoustic medium, so that the ultrasonic waves cannot be satisfactorily transmitted to the subject.

Further, regarding the shape of the ultrasonic coupler, the sectional shape parallel to the ultrasonic scanning direction and the ultrasonic wave transmitting direction is a rectangle or a shape in which the width becomes wider in the ultrasonic wave transmitting direction. The size of the ultrasonic coupler is limited to the outer dimensions of the ultrasonic probe, and the shape of the ultrasonic coupler becomes larger than the area where the ultrasonic beam is transmitted and received. For this reason, it has been a factor that reduces the contactability to the subject or the scannability of the ultrasonic coupler on the subject.

Therefore, an object of the present invention is to provide a novel ultrasonic coupler. Another object of the present invention is to prevent the deterioration of the image due to the retention of the elastic acoustic medium and the bending of the elastic acoustic medium and the inclusion of air bubbles when the ultrasonic coupler is attached to the ultrasonic probe, and to the subject. To provide an ultrasonic coupler with improved contactability and operability.

(Means for Solving the Problems) These various purposes are aimed at elastic acoustic waves that are interposed between the ultrasonic probe and the subject and have a surface that contacts both the transmitting / receiving surface of the ultrasonic probe and the subject. An ultrasonic coupler comprising a medium and a fixing member that accommodates the elastic acoustic medium, has openings on both the ultrasonic probe side and the subject side, and is detachable from the ultrasonic probe, The tip of the elastic acoustic medium projects from the subject-side opening of the fixing member, and the cross section of the projecting portion of the elastic acoustic medium along the direction orthogonal to the ultrasonic wave transmission direction is the subject side of the fixing member. Achieved by an ultrasonic coupler characterized by being larger than the length and width of the opening.

The present invention is also an ultrasonic coupler in which a part or all of the surface of the elastic acoustic medium that contacts the ultrasonic wave transmitting / receiving surface of the ultrasonic probe has a convex curved shape. The present invention further comprises, in the upper part of the ultrasonic probe side opening of the fixing member,
An ultrasonic coupler in which adhesive portions are provided so as to contact at least a pair of opposing side surfaces of the ultrasonic probe, and the interval between the opposing mounting portions is narrower than the width of the ultrasonic probe corresponding thereto. Is. The present invention is also an ultrasonic coupler in which a convex portion or a concave portion is formed on a part or the entire circumference of a side surface of the elastic acoustic medium, and a concave portion or a convex portion is formed on an inner wall of a corresponding fixing member. . The present invention further provides an ultrasonic coupler in which the cross-sectional shape of the ultrasonic coupler parallel to the ultrasonic scanning direction and the ultrasonic wave transmitting direction is formed so that the width becomes narrower in the ultrasonic wave transmitting direction. is there.

(Operation) According to the present invention, the cross-sectional area of the elastic acoustic medium along the direction orthogonal to the ultrasonic wave transmission direction is larger than the length and width of the subject-side opening of the fixing member and the fixing member. Of the elastic member, the surface of the peripheral edge of the opening forming the opening on the subject side of the fixing member presses the protruding portion of the elastic acoustic medium along the fixing member. The retention of the elastic acoustic medium is improved. Further, when the ultrasonic coupler is moved on the subject, the bending of the elastic acoustic body is reduced, so that the transmission / reception of ultrasonic waves is prevented from being deteriorated.

Further, it is desirable that a part or all of the surface of the elastic acoustic medium that contacts the ultrasonic wave transmitting / receiving surface of the ultrasonic probe be formed in a convex curved shape. With such a shape, when the ultrasonic coupler is attached to the ultrasonic probe, bubbles (air) are pushed out, and the ultrasonic wave transmitting / receiving surface of the ultrasonic probe and the elastic acoustic medium in contact with the ultrasonic wave transmitting / receiving surface. It is possible to prevent bubbles from being mixed in between.

Furthermore, it is desirable to make the width of the ultrasonic probe mounting portion of the fixing member narrower than the width of the corresponding ultrasonic probe, so that the mounting portion becomes a sandwich type of the ultrasonic probe, It is possible to prevent the positional deviation from the acoustic wave coupler. Further, by forming a convex portion or a concave portion on a part or the entire circumference of the side surface of the elastic acoustic medium and forming a concave portion or a convex portion of the inner wall of the fixing member corresponding thereto, the holding property of the elastic acoustic medium is improved. Can be improved.

As the elastic acoustic medium, a crosslinked product of an aqueous solution of a water-soluble polymer compound is usually used. Examples of the water-soluble polymer compound include polyvinyl alcohol, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyacrylic acid, polyacrylic acid alkali metal salts, and partially neutralized products of polyacrylic acid with alkali metal, and most preferably. It is polyethylene oxide. The molecular weight of polyethylene oxide is 100,000 or more, preferably 200,0
It is from 00 to 8,000,000.

Crosslinking of the water-soluble polymer compound can be carried out by various methods, such as a method of reacting a polyfunctional isocyanate compound and a polyfunctional epoxy compound, a method of irradiating with radiation, a method of freezing and thawing, and the like. Among these, the method by irradiation with radiation is a preferable method because sterilization can be performed simultaneously with crosslinking.

In the case of crosslinking by irradiation with radiation, an aqueous solution of a water-soluble polymer compound is put in the fixing member, or after the aqueous solution is put in a separate reaction vessel, the polymer is cross-linked by irradiation with radiation. It is carried out by making it three-dimensional and including 80 to 99% by weight, preferably 90 to 98% by weight of water in the fine structure. That is, the water content is 80
If it is less than 100% by weight, the attenuation of ultrasonic waves will increase, while if it exceeds 99% by weight, the mechanical strength of the ultrasonic transmission medium will be poor. The concentration of the water-soluble polymer compound in the aqueous solution is 1 to 20% by weight, preferably 2 to 10% by weight. Furthermore, a preservative and a stabilizer can be added to this aqueous solution.

Radiation used for crosslinking includes γ-rays, electron beams, etc., and γ-rays are preferable. Radiation dose is 0.25
~ 2.5 Mrad, preferably 0.5-1.5 Mrad. That is, if the irradiation dose is less than 0.25 Mrad, the degree of cross-linking is insufficient and it is difficult to maintain its own shape.On the other hand, if it exceeds 2.5 Mrad, it becomes too stiff and insufficient in flexibility. This is because the adhesion to the shape of the part to be contacted is reduced.

(Example) Next, the Example of this invention is described, referring drawings.

As shown in FIGS. 1 to 2 (A) and (B), the ultrasonic coupler according to the present invention includes an elastic acoustic medium 11 solidified in a gel state, and the elastic acoustic medium 11 which is applied to an ultrasonic probe 12. The ultrasonic wave transmitting / receiving surface 12a is in contact with and removable from the fixing member 13. The elastic acoustic medium 11 is, for example, a surface that contacts the subject.
The widths Wa and Wb of 11b are the widths Wa ′ and Wb ′ of the opening on the subject side of the portion of the fixing member 13 that houses the elastic acoustic medium 11.
Are wider along the fixing member 13 and project from the tip of the fixing member 13. That is, the cross-sectional area of the elastic acoustic medium 11 along the direction orthogonal to the ultrasonic wave transmitting direction is formed to be wider than the subject-side opening area of the fixing member 13 and project from the tip of the fixing member 13. There is.

By forming the elastic acoustic medium 11 in this way, as shown in FIG. 2 (A), when the ultrasonic coupler is moved on the subject, the surface 13a of the fixing member 13 on the subject side is elastic acoustic medium. The peripheral edge portion 11c of 11 is pressed down, whereby the bending (deformation) of the elastic acoustic medium 11 is reduced, and the elastic acoustic medium 11
Prevents deterioration of ultrasonic wave propagation due to the retention and flexure of the.
Further, the portion 11a of the elastic acoustic medium 11 that contacts the ultrasonic wave transmitting / receiving surface 12a of the ultrasonic probe 12 has a convex curved shape. Further, on the side surface of the elastic acoustic medium 11, a convex portion 11d or a concave portion (not shown) corresponding to a concave portion 13d or a convex portion (not shown) of the fixing member 13 described later is formed.

The fixing member 13 is made of hard plastics such as polycarbonate, polystyrene and polypropylene,
In the portion 13b in which the acoustic probe 12 is housed, the opening of the fixing member 13 along the outer dimensions of the ultrasonic probe 12 has a length Da and a width Db, and at least a pair of side surfaces of the opening face each other. Attachment part 13b to the ultrasonic probe 12 on the side surface
Is formed. The mounting portion 13b is formed such that the interval L facing each other is smaller than the width L'of the ultrasonic probe 12 corresponding to the mounting portion 13b, and the elasticity of the fixing member 13 sandwiches the ultrasonic probe 12 therebetween. It is configured. Further, as shown in FIGS. 2 (A) and (B),
A concave portion 13d is formed on the inner wall so as to correspond to the convex portion 11d on the side surface of the elastic acoustic medium 11, and the convex portion 11d formed on the side surface of the elastic acoustic medium 11 is fitted into the concave portion 13d,
The elastic acoustic medium 11 is fixed, or is supplied in the state of an aqueous solution and is formed and fixed together with the elastic acoustic medium 11 by being integrated at the same time as crosslinking. Further, as shown in FIG. 2A, the cross-sectional shape of the fixing member 13 perpendicular to the ultrasonic scanning direction and the ultrasonic wave transmitting direction is widened toward the ultrasonic wave transmitting direction. It has a narrowing shape. Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment and can be appropriately modified within the scope of the gist of the present invention.

For example, in the present embodiment, the convex curved portion of the elastic acoustic medium 11 is formed only in the cross section orthogonal to the scanning direction of the ultrasonic wave, but this is a cross section parallel to the scanning direction of the ultrasonic wave or the ultrasonic wave transmitting / receiving surface. It may be formed on the entire surface in contact with. Also,
The concavo-convex portion formed on the side surface of the elastic acoustic medium 11 and the inner wall of the fixing member 13 may be formed on a part or the entire circumference of the side surface, or each concavo-convex portion may be formed reversely. Now, the mounting portion 13b to the ultrasonic probe 12 provided on the fixing member 13
In the present embodiment, is formed only on a pair of opposed side surfaces, but it may be formed on four side surfaces orthogonal to the opening surface.

Further, the present invention can be applied not only to a linear eye probe but also to a single probe, a mechanical scan probe, a convex probe, etc. (see FIG. 3).
In the figure, the same reference numerals as those in FIGS. 1 and 2 (A) and (B) represent the same members).

(Effect of the Invention) As described above, the present invention has a surface which is interposed between the ultrasonic probe and the subject and which contacts both the ultrasonic wave transmitting / receiving surface of the ultrasonic probe and the subject. An ultrasonic coupler including an elastic acoustic medium, and a fixing member that accommodates the elastic acoustic medium, has openings on both the ultrasonic probe side and the subject side, and is detachable from the ultrasonic probe , The tip of the elastic acoustic medium projects from the subject-side opening of the fixing member, and the cross section of the projecting portion of the elastic acoustic medium along the direction orthogonal to the ultrasonic wave transmission direction is covered by the fixing member. Since it is an ultrasonic coupler characterized by being larger than the length and width of the sample side opening, the ultrasonic coupler can be brought into good contact with the subject and the retention of the elastic acoustic medium in the ultrasonic coupler is improved. And the transmission and reception of ultrasonic waves are good It is possible to provide an ultrasonic coupler that can be used to prevent air bubbles from being mixed when the ultrasonic coupler is mounted on the ultrasonic probe and to easily position the ultrasonic coupler and the ultrasonic transmitting / receiving surface of the ultrasonic probe. .

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of an ultrasonic coupler according to the present invention, and FIG. 2 (A) is a front sectional view when the elastic acoustic medium of the ultrasonic coupler of FIG. 1 is attached to a fixing member, Second
FIG. 3B is a side sectional view, FIGS. 3A and 3B are sectional views showing another embodiment, FIG. 4A is a sectional view of a conventional ultrasonic coupler, and FIG. ) Is a side view, FIG.
(C) is a sectional view of a conventional ultrasonic coupler. 11 …… Elastic acoustic medium, 12 …… Ultrasonic probe, 13 …… Fixing member.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-2-243137 (JP, A) JP-A 61-288842 (JP, A) JP-A 2-189137 (JP, A) JP-A 62- 328 (JP, A)

Claims (5)

[Claims] 1. An elastic acoustic medium that is interposed between an ultrasonic probe and a subject and has a surface that contacts both the wave transmitting / receiving surface of the ultrasonic probe and the subject, and the elastic acoustic medium is accommodated therein. In addition, in an ultrasonic coupler having a fixing member that has openings on both the ultrasonic probe side and the subject side and is attachable to and detachable from the ultrasonic probe, the tip end portion of the elastic acoustic medium is the fixing member. Protruding from the subject side opening of
An ultrasonic coupler characterized in that a cross section of the protruding portion of the elastic acoustic medium along a direction orthogonal to the ultrasonic wave transmitting direction is larger than the length and width of the subject-side opening of the fixing member. 2. The ultrasonic coupler according to claim 1, wherein a part or the whole of the surface of the elastic acoustic medium that comes into contact with the ultrasonic wave transmitting / receiving surface of the ultrasonic probe has a convex curved shape. 3. An attachment portion is provided on an upper portion of the ultrasonic probe side opening of the fixing member so as to contact at least a pair of opposing side surfaces of the ultrasonic probe, and a gap between the opposing attachment portions. The ultrasonic coupler according to claim 1 or 2, wherein the width is smaller than the width of the ultrasonic probe corresponding thereto. 4. A convex portion or a concave portion is formed on a part or the entire circumference of the side surface of the elastic acoustic medium, and a concave portion or a convex portion is formed on the inner wall of the fixing member corresponding thereto.
The ultrasonic coupler according to any one of items 1 to 3. 5. The cross-sectional shape of an ultrasonic coupler parallel to the ultrasonic scanning direction and the ultrasonic wave transmitting direction is formed so that the width becomes narrower in the ultrasonic wave transmitting direction. 4. The ultrasonic coupler according to any one of 4 above.