JPS6264342A - Ultrasonic diagnostic apparatus - 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 (a) Field of Industrial Application The present invention relates to an ultrasonic diagnostic device, and particularly relates to a technical improvement that enables diagnosis of lesions covering the entire tissue such as an entire organ. .

(b) Conventional technology and its problems Conventional ultrasound diagnostic equipment obtains tomographic images by displaying the intensity of echoes corresponding to the reflectance. For lesions that differ from normal tissue, effective diagnosis can be made by utilizing the change in reflectance at the boundary where tissue changes occur.

However, in the case of the conventional example having such a configuration, it is hardly effective against lesions where the entire tissue changes, such as fatty liver or liver cirrhosis.

Therefore, in the past, for such lesions, organs had to be removed from the body and diagnosed in vitro, which required surgery and caused pain. was.

The present invention has been made in view of the above circumstances, and it is possible to accurately diagnose the tissue properties in vivo without removing the organ even if there is a change in the entire tissue. The purpose is to make the configuration easier.

(C) Means for Solving the Problems In order to achieve the above object, the present invention includes one first transducer and a plurality of second transducers, One of the transducer and the second transducer is configured for transmitting waves, and the other is configured for receiving waves, and each of the second transducers includes:
Attenuation rate detection means arranged at portions having different ultrasonic transmission distances from the first transducer, and detecting an attenuation rate of the ultrasonic waves as the ultrasonic waves transmit the portions having different distances. and sound speed detection means for detecting the sound speed of the ultrasonic wave based on the distance difference and time difference that occur when the ultrasonic wave passes through the portions having different distances.

(D) Effect For example, if the first transducer is used for wave transmission and the second transducer is used for wave reception, the following will be explained.
For the ultrasound emitted from the first transducer,
Each of the plurality of second transducers has a different maximum value of the received echo, and also has a different time for receiving the maximum echo. The attenuation rate detection means detects the attenuation rate by comparing the maximum amplitude values of the bipedal echoes, and the sound speed detection means sets the time difference in advance by the arrangement of the second transducers. The speed of sound is detected by dividing by the distance difference. These attenuation rates and sound velocities are compared with those in normal tissue to diagnose whether the tissue properties are normal or abnormal.

(e) Examples Hereinafter, the present invention will be explained in detail based on examples shown in the drawings. FIG. 1 is a schematic configuration diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention, and FIG. 2 is a circuit block diagram. In these figures, l is a transmitting transducer, 2a, 2
Reference numerals b designate wave receiving transducers that are arranged at different ultrasonic transmission distances from the wave transmitting transducer l.

A pulser circuit 3 is connected to the wave transmitting transducer 1, and is configured to oscillate ultrasonic pulses at set time intervals based on a command signal from a control circuit 4.

Each of the transducers 2 a and 2 b includes an amplification circuit 5 a that amplifies the received ultrasonic signal.
, 5b, detection and peak hold circuits 6a and 6b that detect the amplified ultrasonic waves and extract the maximum amplitude value of the ultrasonic waves, and the number of points at which the maximum amplitude value is extracted from the control circuit 4. Peak hold time counters 7a and 7b are connected to the counters 7a and 7b, which measure the number of oscillated ultrasonic pulses based on the signal.

The amplitude value outputs A , , A , from each of the detection and peak hold circuits 6 a and 6 b are input to the attenuation factor calculation circuit 8, and the ratio of both amplitude values A , , A , is calculated as well as the ratio A t The attenuation rate detection means 9 is configured to detect the attenuation rate per unit length by multiplying /A by a predetermined constant B.

The outputs from the peak hold time counters 7a and 7b are inputted to the sound velocity calculation circuit 10, and based on the outputs j+ and jt at the peak hold time, a predetermined constant C is set to the reception time difference (111+) for each of the oscillated ultrasonic pulses. The speed of sound detection means 11 is configured to detect the speed of sound by multiplying . In addition, each of the constants B and C is a numerical value (1/r) for dividing by the ultrasonic transmission distance difference r specified in advance by the installation position of both receiving transducers 2a and 2b, or , a value obtained by multiplying that value by a predetermined coefficient is set.

12 is the attenuation rate detection means 9 and the sound velocity detection means 11
This is a display circuit that displays each detection result, and by comparing the displayed attenuation rate and sound speed with the attenuation rate and sound speed when the tissue is normal, it is possible to diagnose whether the tissue is normal or abnormal. It looks like this.

Next, the operation of this embodiment will be explained.

When an ultrasonic pulse is emitted from the wave transmission transducer ff7-sa1 toward a living tissue, the ultrasonic pulse is scattered within the living body. The receiving transducers 2a and 2b each receive the reflected ultrasonic waves.

At this time, in each of the receiving transducers 2a and 2b, as schematically shown in FIG. A straight line connecting the installation position (first straight line:
The right-angled apex of a right-angled isosceles triangle whose hypotenuses are the straight line connecting the second wave receiving transducer 2b and the installation position of the other wave-receiving transducer 2b (second straight line: length L2). When receiving ultrasonic waves reflected by X and Y,
Its amplitude value becomes maximum. Therefore, the tops X, Y
A circuit that calculates the attenuation rate from the amplitude value based on the reflected ultrasonic waves received from each, calculates the speed of sound based on the reception time of the reflected ultrasonic waves from each of the tops X and Y, and displays these attenuation factors and the sound speed. 12.

Now, if the length of the second straight line is twice the length Ll of the first straight line, then the receiving transducers 2 a, 2
The transmission distance difference r of the ultrasonic waves received at each b is the top
, Y is twice the distance, and r(Ll. Based on this distance difference r, the constant B.

C is set, and as the ultrasonic wave passes through parts having different distances, the attenuation rate and sound speed of the ultrasonic wave can be detected.

In the above embodiment, one transmitting transducer and two receiving transducers are provided, but three or more receiving transducers may be provided. Completely opposite to the example, one receiving transducer and multiple transmitting transducers are provided, and each transmitting transducer emits ultrasonic waves at the one with the longest transmission distance. The ultrasonic pulse may be configured to oscillate in a time-division manner at predetermined intervals set to a time longer than the time it takes for the wave to be received. The second thing to provide is
Each is called a transducer.

Further, the installation positions of the second transducers are not limited to equal intervals, but may be set at any desired intervals.

(f) Effects As described above, according to the present invention, ultrasonic waves are prevented from transmitting so that there are parts with different ultrasonic transmission distances, and the attenuation rate and sound speed are detected based on this. When detecting attenuation rate and sound velocity using one transducer and one receiving transducer, each patient has different properties of the entire body, such as different thicknesses of subcutaneous fat, and it is difficult to detect However, compared to
It takes the difference in the speed of sound and eliminates the above errors in both cases. It can detect both the attenuation rate and the speed of sound with high accuracy and diagnose in vivo. It is useful for lesions where the entire tissue changes, such as fatty liver and cirrhosis. It is now possible to diagnose cancer without having to remove organs and cause pain to the patient.

In addition, it may include one transmitting transducer and a plurality of receiving transducers, or it may include one receiving transducer and a plurality of transmitting transducers. , it is now possible to simplify the configuration by simply providing a circuit for processing the received signal in the receiving transducer.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention, and FIG. 2 is a circuit block diagram. DESCRIPTION OF SYMBOLS 1... A transducer for transmitting waves as a first transducer, 2 a, 2 b... A transducer for receiving waves as a second transducer, 9... Attenuation rate detection means, 11 ...Sound velocity detection means.

Claims (2)

[Claims] (1) One first transducer and a plurality of second transducers, one of the first transducer and the second transducer is configured for wave transmission, and the other is configured for wave reception, and the second Attenuation rate detection in which the transducers are arranged at different ultrasonic transmission distances from the first transducer, and the attenuation rate of the ultrasonic waves is detected as the ultrasonic waves are transmitted through portions having different distances. and a detection means for detecting the sound speed of the ultrasound from the distance difference and time difference as the ultrasound passes through the portions having different distances. (2) The ultrasonic diagnostic apparatus according to claim 1, wherein the first transducer is a transmitting transducer, and the second transducer is a receiving transducer.