JPS618036A - Ultrasonic probe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an ultrasonic probe for an ultrasonic diagnostic apparatus that inspects the inside of a subject by transmitting and receiving ultrasonic signals.

Configuration of conventional examples and their problems Few conventional ultrasonic probes can be used particularly in the oral cavity. The present applicant has proposed an ultrasonic probe shown in FIG. 1 for use in the oral cavity, particularly for diagnosis of teeth and periodontal areas. (
a) shows a front view, and (b) shows a side view. Ultrasonic transducer 1
is housed in an ultrasonic cell 2 together with a first ultrasonic propagation medium 3, a second ultrasonic propagation medium 4, and a boundary wall 5 separating them.

A driver 6 and a motion transmission shaft 7 for mechanically scanning the ultrasonic transducer 1 in a fan-like or linear manner are coupled to the ultrasonic transducer 1. A membrane 8 made of a flexible thin film is provided on the front surface of the ultrasonic cell 2, and is adapted to come into close contact with the tooth or periodontal region of the subject 9. In such an ultrasonic probe, different materials can be selected for the first and second ultrasonic propagation media 3 and 4, and it is also possible to prevent corrosion of the metal inside the ultrasonic cell 2. However, if the membrane 8 is damaged, in order to repair it, in addition to replacing the membrane 8, the second ultrasonic propagation medium 4 is also ensured.
You will need to fill it with liquid.

First, replacing the membrane 8 is relatively easy if, for example, the membrane 8 is configured to be detachable from the ultrasound cell 2. However, in reality, the membrane 8 is strongly pressed against the subject 9, which tends to cause fluid leakage from the attachment/detachment part.Furthermore, if the membrane 8 cannot be attached or detached, this replacement may be difficult. Become. Preventing air bubbles from being mixed in when filling the broken second ultrasonic propagation medium 4;
Furthermore, there are many problems such as preventing liquid leakage after filling the liquid.

In particular, in most cases, these methods cannot be implemented by doctors who use them.

One way to prevent these problems is to provide a water bag on the front surface of an ultrasound probe for a medical ultrasound diagnostic apparatus. However, conventional water bags have a bag shape made of one type of material such as silicone rubber or natural rubber, or have a stopper around the bag shape to fix it to the outer casing of the ultrasound probe. There is. When a water bag with such a structure is applied to an ultrasonic probe that operates at a frequency of 10 to 20 MHz, which is used for precise diagnosis of the oral cavity, especially the periodontal region and diagnosis of the alveolar bone, the following problems arise. . First, conventional water bags require mechanical strength because they are attached to relatively large ultrasound probes, and because they are used at frequencies of 3 to 7 MHz, the membrane is thick and the amount of ultrasound attenuation increases. , the sensitivity decreases.

Second, if you use a thin natural rubber-based water bag, it will deteriorate rapidly due to UV rays, and you will need to replace the water bag frequently.

Furthermore, silicone rubber-based materials have a relatively thick film and are difficult to adhere to teeth and irregularities in the periodontal region.

Purpose of the Invention The present invention has been made in order to solve the above-mentioned conventional problems.It is an object of the present invention to provide a high-quality diagnostic image that can be safely applied in the oral cavity, is extremely easy to handle, and With the goal.

Structure of the Invention In order to achieve this object, the present invention includes an ultrasonic transducer that transmits and receives ultrasonic waves, fills a first ultrasonic propagation medium with low ultrasonic attenuation, and seals the ultrasonic wave with a membrane. The cell is made up of a cell and two types of thin films on its front surface, and ultrasonic diagnosis is performed by placing a second ultrasonic medium inside. 2 is a side sectional view showing an ultrasonic probe in an embodiment of the present invention. The ultrasonic transducer 1 is housed in an ultrasonic cell 2 together with a first ultrasonic propagation medium 3, such as glycols such as ethylene glycol and polyethylene glycol, or water. In front of the ultrasonic cell 2, there is a thin membrane 1o, such as silicone rubber of 20-30 μm or less, rubber such as butadiene rubber (hereinafter abbreviated as BR), ethylene propylene rubber (hereinafter abbreviated as KPR), or TP of about 100 μm. X (4-methylpentene-1) is attached, and furthermore, a water bag 11 is attached to the front surface of the membrane 10 in close contact with the membrane 10 via a thin layer of water or the like. The water bag 11 includes a first thin film 12 on the ultrasound cell side, for example, a rubber thin film such as BR or EPR of 10 to 20 μm, and a second thin film 13 on the side in contact with the subject 9, for example, thinner than the previous thin film 12. It is made of thick, mechanically and chemically strong and stable rubber such as BR or EPR of 20 to 30 μm or more, and a second ultrasonic propagation medium 4, such as water or saline solution, is flowing inside. .

Further, in the upper part of the water bag 11, there is a recess 1 on the side surface of the ultrasonic cell 2.
It has a fixing part 14 that can be attached to and fixed to 6.

Ultrasonic transducer 1 via motion transmission @7.

and is connected to the drive unit. Still, ultrasonic transducer 1
Although not shown here, is connected to a transceiver, generates an ultrasound signal, and transmits the ultrasound into the subject 9.

The signal reflected within the subject 9 is received again by the ultrasound transducer 1, processed by the receiver, and then displayed as an ultrasound tomographic image, which is used for diagnosis of the subject 9.

When the above-mentioned ultrasonic probe is used, the ultrasonic signal passes through the first and second ultrasonic propagation media 3.4 and the membrane 10. The first and second thin films 12 and 13 each have an acoustic impedance of 1.6 to 1. Weight: 106kg/m'・
S, the number of ultrasonic waves reflected at each boundary is small, and the ultrasonic attenuation is also small, making it a highly sensitive ultrasonic probe. ) 12 does not come into direct contact with the subject 9, so it is possible to change some characteristics compared to the outer thin film (second thin film) 13, and it is desirable to do so.

For example, the inner thin film 12 does not need to have excessive values in terms of mechanical strength, chemical stability, etc. than the outer thin film 13;
It can be made thinner. Furthermore, the inner thin film 12
The same material as the membrane 10 is used, for example, a hard-to-stretch rubber such as butane rubber (Japan Synthetic Rubber's JSR830), and the outer thin film 13 is made of butadiene rubber JSR8.
Use a comb like No. 10 that is easy to stretch.

With this configuration, the membrane 10 and the inner thin film 1
2 has good adhesion and ultrasonic permeability is good. Furthermore, since the outer thin film 13 is easily stretchable, even when the ultrasonic probe is pressed against the tooth or periodontal region of the subject 9, the adhesion is good and a good ultrasonic tomographic image can be obtained. In addition, since it is made of homogeneous rubber, it is easy to make it into a bag.

Next, the outer thin film 13 of the water bag 11 is made of ethylene propylene rubber, which is chemically more stable than the inner thin film 12 and has strong weather resistance. Ethylene propylene rubber has an acoustic impedance of approximately 1.6X10'kg g//ir]t
-s, a thin film of 20 to 30 μm can be easily produced. The inner thin film 12 may be made of ethylene propylene rubber, but it may also be made of butadiene rubber, which allows an even thinner film to be made. With such a configuration, it is possible to obtain an ultrasonic probe that is less likely to be degraded by ultraviolet rays, is durable, has good adhesion, and is highly sensitive.

In order to attach the water bag 11 as described above to the front of the ultrasonic cell 2, it is shown in FIG. As shown in FIG.
form 4.

In another configuration, as shown in Figure 4 ((a) is an external view, fb) is a sectional view taken along line BB' in (a), the thin films 12 and 13 on both sides are made of plastic or the like on the upper part. The ultrasonic cell is attached to the fixing part 14, and attached to the ultrasonic cell via the fixing part 14.

With this structure, it is easy to attach and detach the water bag to the ultrasound cell, and even if the water bag is damaged, the doctor who uses it can easily replace it. Furthermore, when it is pressed strongly against the subject, there is no leakage from the part fixed to the ultrasonic cell as in the conventional case.

As described in detail, the ultrasonic probe of the present invention has higher sensitivity by attaching a water bag made of two types of thin films to an ultrasonic cell containing an ultrasonic transducer. It becomes an ultrasonic probe, improves adhesion to the subject, and also has better weather resistance and durability. In addition, repair when the water bag is damaged.

It has the advantage of being easy to replace and being safe without causing any liquid leakage.

[Brief explanation of drawings]

Fig. 1 (&) is a front view showing an ultrasonic probe previously proposed by the applicant, Fig. 1 (b) is a side view thereof, and Fig. 2 is an intraoral probe according to an embodiment of the present invention. Fig. 3 (IN) is a side sectional view showing the ultrasonic probe of the present invention, Fig. 4 (a) is an external view showing the water bag attached to the ultrasonic probe of the present invention, Fig.
1)) and 4('b) are cross-sectional views showing a water bag attached to the ultrasonic probe of the present invention. 1... Ultrasonic transducer, 2... Ultrasonic cell, 3... First ultrasonic propagation medium, 4...
・Second ultrasonic propagation medium, 11...Water bag, 12
...Inner/side thin film, 13...Outer thin film. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure + a) Figure 2 Figure 3

Claims (5)

[Claims] (1) an ultrasonic transducer that transmits and receives ultrasonic waves; an ultrasonic cell that includes the ultrasonic transducer and houses a first ultrasonic propagation medium; and a part of the ultrasonic cell that is provided, A membrane part that transmits ultrasound emitted from an ultrasonic transducer, and a water bag that covers the membrane part and is detachably attached to the ultrasonic cell, and the water bag is provided on the side of the membrane part. It is characterized by comprising a first thin film, a second thin film provided on the opposite side thereof, and a second ultrasonic propagation medium housed inside surrounded by the first and second thin films. Ultrasonic probe. (2) Claim 1, characterized in that the first and second thin films constituting the water bladder are made of the same material, and the first thin film is thinner than the second thin film. Ultrasonic probe as described. (3) The ultrasonic probe according to claim 1, wherein the first thin film constituting the water bladder is made of a material with less elongation than the second thin film. (4) The ultrasonic probe according to claim 3, wherein the first and second thin films are composed of two types of butadiene rubbers having different compositions. (5) The ultrasonic probe according to claim 1, wherein the first thin film constituting the water bladder is made of butadiene rubber, and the second thin film is made of ethylene propylene rubber.