JPH0226968B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an ultrasound-based language function diagnosis device, and in particular, an ultrasound-based language function diagnosis device that is capable of obtaining a visual image of the tongue profile associated with pronunciation. Regarding.

(Technical Background of the Invention) Various types of ultrasonic diagnostic devices are known.
Mode devices and M-mode devices that display the movements of various parts of the circulatory system are known ('84ME Equipment Technology Overview, Denshi Keizoku Publishing Co., Ltd., April 1, 1984).

As shown in FIG. 6, these devices continuously display reflected pulses 61, 62, and 63 obtained by reflecting an emitted pulse 60 from a probe inside the body on a cathode ray tube or the like.

Since the purpose of such an apparatus is to obtain an accurate tomographic image, it is expected that the scanning period of the probe can be shortened and that even small reflected pulses can be accurately depicted. Regarding this, the above-mentioned publication states, ``When creating a static ultrasound image of the heart in synchronization with the heartbeat, if one screen is created in a short period of less than 30ms in synchronization with the heartbeat, it will be possible to Even for parts that move rapidly, images that can be regarded as cross-sections at a certain instant can be obtained.Such images can be captured at 30 times per second
If you make a few pieces, you can observe the heart in its natural state. "It has said.

Conventional devices of this type have recently been used for the diagnosis and correction of language function.

In other words, if there is some kind of language disorder, the shape of the tongue when pronouncing a certain sound (for example, "a") is measured, and the abnormality or disorder can be determined by measuring the shape of the tongue when pronouncing it normally. Diagnosis can be made by comparing. Furthermore, pronunciation training can be performed by showing the disabled person the shape of the tongue required for normal pronunciation.

For this purpose, in order to judge the state of abnormal pronunciation from the shape of the tongue and conduct training, it is necessary to know only the basic shape (profile) of the tongue, and it is necessary to understand the ever-changing tongue profile. It is necessary to know the average shape of

However, according to the conventional device described above, since the purpose is to observe the movement of human body tissues and organs in detail, the signals regarding the detailed parts of the human body tissues get in the way, making it difficult to grasp the accurate tongue profile. It was difficult. Furthermore, as mentioned above, although it is possible to observe moving tissues using the M-mode device, even if you observe the moving state of the tongue, it is difficult to practice pronunciation using this device. This was not possible since the tongue profile was not shown.

In addition, particularly with this type of conventional device, it has not been possible to correct changes in the distance between the palate and the probe and between the palate and the tongue to depict the correct relative relationship of the tongue in the oral cavity.

That is, since the distance between the probe and the roof of the mouth varies with each pronunciation, in order to accurately determine language function, it is necessary to accurately understand the relationship between tongue movements and the roof of the mouth.

For example, consider the pronunciation of "Ka". First of all,
To pronounce the phoneme "k," the central part of the tongue in front-back cross section comes into contact with the roof of the mouth, causing the breath to be held. Next, a gap is created between the tongue and the roof of the mouth, allowing the breath to pass through, leading to the tongue pronouncing the vowel "a," which does not touch the roof of the mouth.

Even if we try to correlate the static image of the palate that has been registered in advance with the profile of the tongue from time to time, the tension of the geniohyoid muscle on the submandibular surface and the opening and closing of the oral cavity occur during pronunciation. As a result, the relative distance changes, making it impossible for conventional devices to grasp accurate positional relationships.

(Object of the Invention) The present invention has been made in an attempt to eliminate the above-mentioned drawbacks of the prior art. An object of the present invention is to provide an ultrasonic language function diagnostic device that can accurately display the positional relationship of the user.

(Summary of the invention) In order to achieve this object, according to this invention,
The current data of the reflected signal obtained by scanning the ultrasound probe is averaged with the past data for each scan, and the maximum value of this average value for each scan is interpolated to depict the tongue profile. At the same time, an image reading means such as a video camera is used to read the external appearance of the human body, calculate and output the relative positional relationship of surrounding tissues of the tongue edge, and display the combined result with the tongue profile data. .

(Embodiments of the invention) Examples of the invention will be described below with reference to the accompanying drawings. Note that the same reference numerals in each figure indicate similar objects.

FIG. 1 shows an embodiment of the invention.

In the figure, 10 is an ultrasound probe, 11 is a transmission circuit, 12 is a scanning circuit, 13 is a pre-signal processing circuit, 14 is an AD converter, 15 is an image signal forming circuit, 16 is a video signal processing circuit, and 17 is a display. circuit, 18 is a control circuit, 20 is image reading means, 2
1 is a peripheral image data memory, and 22 is a peripheral image data calculation circuit.

The probe 10 emits ultrasonic waves of a specific frequency, and various types of probes are known for medical use. This type of probe has both transmitter and receiver functions in one unit, and is connected to the lower jaw 2 as shown in Figure 2.
0 and perform measurement.

Ultrasonic waves are reflected at the interface when there is a change in the acoustic impedance of the medium through which they are transmitted. The impedance of the human body's muscle tissue is close to that of water, and is approximately 4000 times the impedance of the air layer assumed at the upper edge of the tongue, resulting in a large level of reflected waves. Additionally, although there is an impedance difference within the tissue of the tongue, it is not at the same ratio as between the tongue and the air, and the level of the reflected wave is extremely small. Furthermore, when the tongue is in contact with the palate, reflected waves are obtained from the palatal bone 22, but the impedance of the bone is approximately four times that of water, and the level of the reflected waves is lower than when the upper edge of the tongue is an air layer. It doesn't get bigger. In this case, information is obtained that the upper edge of the tongue of interest is located close to the palatine bone.

Such a probe 10 can be scanned by various electronic methods as shown in FIG. 3 while being held in the position shown in FIG. That is, FIG. 3a shows the linear scanning method. Here, the probe 10 includes a plurality of vibrators 10A, 10
B, 10C, ... and electronic switches SW1, SW2, connected in series with these, respectively.
It has SW3,...

The scanning circuit 12 sequentially turns on one of the electronic switches (switch SW3 in the figure).
In synchronization with this, the transmitting/receiving section 31 activates the corresponding vibrator.

In contrast, FIG. 3b shows a sector scanning method. In this case, a plurality of vibrators 10A, 10B, 1
0C, . . . are provided with delay means DL1, DL2, DL3, . . . each driven by a scanning circuit 12. The delay time of each delay means can be changed by the scanning circuit 12. Further, since a common signal is input from the transmitting/receiving section 31 to each delay means, one wavefront 36 is formed by the delay characteristics of the delay elements DL1, DL2, DL3, .
Therefore, by continuously changing the delay characteristics of the delay means by the scanning circuit 12, the angle θ of the normal N2 of the wavefront 36 with respect to the normal N1 of the probe 10 is continuously changed from +45 degrees to -45 degrees. Scanning can be performed by varying the

The transmitting circuit 11 is for energizing the probe 10 and causing it to emit ultrasonic waves of a predetermined frequency. Further, the scanning circuit 12 performs scanning similar to that described in FIG. 3.

The pre-signal processing circuit 13 performs waveform shaping and amplification of the received signal. In particular, a function that increases the gain of the amplifier immediately after pulse transmission to compensate for the attenuation of reflected waves due to distance, a logarithmic amplification function that makes it possible to handle reflected signals with a wide dynamic range, and It has a detection function to obtain amplitude information.

The AD converter 14 converts the output signal of the pre-signal processing circuit 13 into a digital signal.

The image signal forming circuit 15 is as shown in FIG. According to the figure, the circuit 15 includes a buffer memory 41, an averaging processing circuit 42, and a data memory 4.
3. Maximum distance calculation circuit 44, buffer memory 4
5, interpolation processing circuit 46, and image signal synthesis circuit 4
It has 7.

The buffer memory 41 is for temporarily storing data obtained by each scan. The contents of this buffer memory 41 are sequentially transferred to the averaging processing circuit 42. Therefore, the current data is held in the buffer memory 41,
The data memory 43 stores past addition average data.

The averaging processing circuit 42 includes a buffer memory 41
The data characteristics are extracted from the current data and the past addition average data of the data memory 43, and the S/N is
This is an effective circuit for improving. That is,
Considering that the subject of measurement or diagnosis by the device of the present invention is the constantly moving tongue, the proportion of previous data in the calculation results decreases exponentially.

Y _o = Y _o-1 + (X _o − _{Y o-1} )/K (Y _o is the result of this calculation, Y _o-1 is
The previous calculation result, X _o , is the current data,
K is the addition weight).

In the above equation, since the signal is input regularly, the calculation result is such that the signal level is maintained. However, in the case of noise, since the signal is irregular, the calculated result will be lower than the level at the time of sampling. Therefore, the S/N of the reflected signal is improved and features are extracted, making it easier to identify the upper edge of the tongue and the palatine bone.

For example, assume that curves 51 and 52 in FIG. 5 are profiles in the longitudinal direction A of the tongue (FIG. 2) at certain moments T1 and T2 when pronouncing "a". Here, the tongue position in the scanning direction (arrow T1) at time T1 and the tongue position in the scanning direction (arrow T2) at time T2 belong to completely different profiles, and these positions cannot be connected. But I can't get any meaningful profile. For this purpose, the method of averaging is used to create a relationship between current and past data.

The data memory 43 is a memory capable of storing averaged data for each scanning direction specified by the scanning circuit 12 that drives the probe 10, and has a memory area of a predetermined bit (for example, 128 bits) for each direction. . According to the present invention, it is only necessary to specify, for example, eight scanning directions, so the memory area also becomes eight.

The maximum distance calculation circuit 44 is a circuit for specifying the position of the tongue in each scanning direction. for example,
Scanning direction T1 in profile curve 51 in FIG.
Since there are various types of reflected waves also in , the received waveforms are as shown in waveforms 61, 62, and 63 in FIG. Therefore, for the reason mentioned above, the signal having the maximum level is extracted as the signal corresponding to the position of the tongue (signal 62 in FIG. 6). Also, at this time,
Since the range of a certain distance of the tongue can be predicted in advance, it is effective to limit the range within the predictable range when determining the maximum level. For this reason,
The maximum distance calculation circuit 44 sequentially compares each data in the same scanning direction and extracts and calculates the largest one.

The buffer memory 45 includes the maximum distance calculation circuit 44
The output signals of , that is, the signals corresponding to the position of the tongue in each scanning direction, are accumulated for all scans of one measurement.

The interpolation processing circuit 46 forms an image signal corresponding to one curve passing through each point indicated by this data, based on all the position data accumulated by the buffer memory 45 in one measurement. This image signal QD
is the relative data formation system R in the image signal synthesis circuit 47.
The video signal processing circuit 1 is synthesized with the signal RD from
6, it is converted to analog, and the brightness is modulated, etc.
It is displayed on a display circuit 17 such as a CRT.

FIG. 7 shows how the tongue profile is displayed. Through eight sampling scans from S1 to S8, data corresponding to each point indicated by an "x" mark is obtained, and a single curve 70 passing through each point is the tongue profile corresponding to a certain pronunciation. will be displayed as .

However, such display must be accurately displayed in relation to the palate. For this reason, relative data formation system R is used.

This relative data formation system R includes an image reading means 20, a peripheral image data memory 21, and a peripheral image data calculation circuit 22.

The image reading means 20 is, for example, a video camera, and may be any device that can observe the appearance of the human body. CCD also as an optical means
Various methods such as arrays are possible, and other methods such as thermal methods may also be used.

The peripheral image data memory 21 stores all the data read by the image reading means 20.

As shown in the schematic diagram of the head in FIG.
0 position is the distance L1 between the top of the head 81 and the chin 80
The position of the palate 82 is calculated and output from this distance L1 as the distance L2 from the top of the head 81. By combining the palate data obtained through such calculations with data representing the tongue profile, the relative positional relationship of the tongues in a particular pronunciation can be accurately grasped. For example, in the pronunciation of "Ka" mentioned above, the relative distance between the tongue 83 and the palate 82 when pronouncing "k",
The relative distance when pronouncing "a" can be calculated and output as data, and this can be displayed.

The timing of scanning, sampling, display, etc. as described above is determined by command signals a to i of the control circuit 18.

Next, the operation of this embodiment will be explained with reference to the flowchart of FIG. In the following explanation, the numbers 91 to 102 correspond to the numbers of each step in the flowchart.

When the apparatus is started (91), the control circuit 18 sets the probe 10 at the initial position so that it can emit ultrasonic waves using the command signal b. Subsequently, the control circuit 18 sends out a command signal a, and the transmitting circuit 11 activates the probe 10 to cause it to emit ultrasonic waves 9
2.

At the same time when the transmitting circuit 11 is activated by the command signal a, command signals c, d, e, g, h, and i are also sent out.
The AD converter 14 starts sampling 93 the received signal, and the relative data forming means 20 records the state of the subject's pronunciation.

When a digital signal is formed by this sampling 93, the image signal forming circuit 16 executes an averaging process 94 and a maximum distance calculation process 95,
The result is stored 96 in the buffer memory 45 (FIG. 4).

At the timing of storage in the buffer memory 45, the control circuit 18 checks 97 whether scanning has been completed in eight predetermined directions. When the number of scans has not reached eight, the control circuit 18 sends command signals a and b to change the scan direction 98;
The transmission-memory storage cycle described above is executed again.

When all scanning is completed in this way, the stored contents of the buffer memory 45 are read out 99, and the above-mentioned interpolation process is executed 100 using this data to form an image signal QD.

Meanwhile, during this time, the relative data formation system R is reading and storing the above-mentioned data. Therefore, the peripheral image data calculation circuit 22 determines how to combine the output signal QD with the output signal RD. For example, in the pronunciation of "Ka" mentioned above, two states, "k" state and "a" state, should be displayed, and as shown in FIG. 10, for one tongue profile 83, A signal RD is sent to sequentially display the two states a and b. Such a display number can be input in advance from the control circuit 18 depending on what sound is to be produced.

Such a composite display is executed (101), the capture process is completed (102), and these steps are sequentially repeated.

In addition, in the above embodiment, the case where the profile of the tongue in the longitudinal direction is obtained was explained.
It is likewise possible to obtain a profile in the width direction of the tongue. Furthermore, two types of probes, one in the length direction and the other in the width direction, may be provided. Furthermore, the number of scans is 8.
Of course, it is not limited to times.

(Effects of the Invention) The present invention averages the current data of the reflected signals obtained by scanning the ultrasonic probe with the past data for each scan, and calculates the maximum value of this average value for each scan. The tongue profile is depicted using data that interpolates values, and the relative positional relationship between the tongue and surrounding tissues of the tongue edge is calculated and output, and the result is combined with the tongue profile data and displayed. By doing so, it is possible to obtain a language function diagnosis device using ultrasound that has the following effects.

(1) Since only the profile of the tongue can be displayed and the relative position of the tongue with the surrounding tissues can be displayed accurately, disorders in language function can be clearly understood and correction can be carried out reliably.

(2) As a result of the above, abnormalities in the tongue profile of speech-impaired people can be diagnosed and can be useful for correction.

(3) Even if used for a long time, it has no effect on the human body like X-rays, so it is highly safe.

(4) Since fewer scanning directions are required, the memory can be made smaller.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an embodiment of this invention, Fig. 2 is an explanatory diagram showing how the probe is set, Fig. 3 is an explanatory diagram showing how the probe scans, and Fig. 4 is an embodiment of the invention. Fig. 5 is an explanatory diagram of the relationship between temporal changes in the tongue and sampling when sampling the tongue profile, Fig. 6 is a diagram of the relationship between transmitted pulses and received reflected pulses, and Fig. 7 is an explanatory diagram of an image drawn by an image signal obtained by interpolation processing, FIG. 8 is an explanatory diagram of the operation of the embodiment of this invention, and FIG. 9 is an explanatory diagram of the operation of the embodiment of this invention. FIG. 10 is a flowchart illustrating another operation of the embodiment of the present invention. 10... Ultrasonic probe, 11... Transmission circuit, 12
...Scanning circuit, 13...Pre-signal processing circuit, 14...
AD converter, 15... Image signal forming circuit, 16... Video signal processing circuit, 17... Display circuit, 18... Control circuit, 20... Image reading means, 21... Peripheral image data memory, 22... Peripheral image data calculation circuit, 4
1, 45...Buffer memory, 42...Averaging processing circuit, 43...Data memory, 44...Maximum distance calculation circuit, 46...Interpolation processing circuit, R...Relative data forming circuit.

Claims (1)

[Scope of Claims] 1. A probe capable of transmitting and receiving ultrasonic waves with respect to the oral cavity, a transmitting means for energizing the probe to transmit ultrasonic waves, and a tongue edge in the oral cavity that transmits the ultrasonic waves emitted by the probe. a receiving means for forming an image signal based on a reflected signal obtained by receiving a reflected wave at the probe with the probe, and a continuation of the tongue edge obtained by scanning the oral cavity with the probe. In the language function diagnosis device for diagnosing language function using images, the receiving means adds and averages current data of the reflected signal obtained by scanning the probe to past data for each scan, and calculates the average Relative data forming means includes means for outputting data for interpolating the maximum value for each scan as the image signal, and further reads the appearance of the human body and calculates and outputs the relative positional relationship of the surrounding tissues of the tongue edge. A language function diagnostic device using ultrasound, characterized in that the output of the relative data forming means is combined with the output of the receiving means and displayed.