JPH09519A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE: To prevent ultrasonic power from being employed more than necessary by setting an allowable valtje for ultrasonic wave exposure time in accordance with outputs from an information storage means, and stopping exposure to ultrasonic waves at the moment when the measured elapsed time from the start of the exposure to ultrasonic waves exceeds the allowable value. CONSTITUTION: A requirement table which reflects the temperature rise inside a living body due to exposure to ultrasonic waves is stored in an information storage means 61, and an allowable value for ultrasonic wave exposure time is selected from information in an ultrasonic power information table in accordance with requirements for exposure to ultrasonic waves and is set. It is determined whether or not the elapsed time (ultrasonic wave exposure time) from the start of the exposure to ultrasonic waves, as measured by an exposure time measuring means 63, has exceeded the allowable value of the ultrasonic wave exposure time, and the exposure to ultrasonic waves is stopped by driving an automatic freezing means 64 at the moment when the ultrasonic wave exposure time exceeds the allowable value. Therefore, ultrasonic waves not exceeding the level of ultrasonic power beyond which they may affect an examinee can be employed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to measuring the elapsed time from the start of ultrasonic irradiation,
The present invention relates to an ultrasonic diagnostic apparatus capable of preventing an ultrasonic wave from being used more than necessary by applying an automatic freeze when the elapsed time becomes larger than an allowable value to stop ultrasonic wave irradiation.

[0002]

2. Description of the Related Art A conventional ultrasonic diagnostic apparatus is an apparatus for irradiating an ultrasonic beam into a body of a subject and capturing a reflection echo thereof to reconstruct an image of the subject. , A B-mode image, an M-mode image and the like are provided to provide a diagnostic sample.

In this conventional ultrasonic diagnostic apparatus, an ultrasonic beam may be applied to the inside of the subject for a long time, and at this time, the temperature inside the living body may rise and abnormal tissue may occur. Therefore, the conventional ultrasonic diagnostic apparatus has a display function of displaying the ultrasonic power information currently radiated at a position where the operator can visually check it.

[0004]

The present inventor has found the following problems as a result of examining the above-mentioned conventional techniques.

That is, in the conventional ultrasonic diagnostic apparatus, there is a problem that it is difficult for the operator to keep an eye on the display function, especially when he is busy with diagnosis.

Further, it becomes rare to use an ultrasonic wave power more than necessary in the diagnosis, and the user is accustomed to this, and normally, the display function is not watched. Therefore, there has been a problem that the limit of the ultrasonic power is exceeded without the operator's knowledge, the temperature inside the living body rises, and abnormal tissue occurs.

An object of the present invention is to provide an ultrasonic diagnostic apparatus in which ultrasonic power is not used more than necessary.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0009]

The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows.

That is, the ultrasonic diagnostic apparatus according to the present invention has information storage means for storing condition information reflecting the temperature rise in the living body due to ultrasonic irradiation and output of the information storage means permits the ultrasonic irradiation time. The irradiation time setting means for setting a value, the irradiation time measuring means for measuring the elapsed time from the start of ultrasonic irradiation, and the ultrasonic irradiation time measured by the irradiation time measuring means were set by the irradiation time setting means. It is provided with an automatic freeze means for stopping the irradiation of ultrasonic waves when it becomes larger than the allowable value.

[0011]

According to the above-mentioned means, the information storage means for storing the condition information reflecting the temperature rise in the living body by the ultrasonic irradiation is provided, and the information storage means stores the temperature rise in the living body by the ultrasonic irradiation. The condition information to be reflected is stored.

Then, the allowable value of the ultrasonic wave irradiation time is set from the information in the information storage means based on the ultrasonic wave irradiation conditions.

On the other hand, the irradiation time measuring means measures the elapsed time from the start of ultrasonic irradiation (ultrasonic wave irradiation time), and when the measured elapsed time exceeds the preset allowable value, the automatic freeze is performed. The ultrasonic irradiation is stopped by the means. This can prevent the ultrasonic power from being used more than necessary.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings together with embodiments.

FIG. 1 is a block diagram showing the schematic arrangement of an embodiment of the ultrasonic diagnostic apparatus according to the present invention.

In FIG. 1, 10 is an ultrasonic probe and 20 is an ultrasonic probe.
Is a subject, 30 is an ultrasonic wave transmitting / receiving means, 40 is a signal processing means, 50 is a processing / control means, 51 is an A / D converter, and 52 is
Is a scan converter, 53 is a D / A converter, 54 is a central processing unit (CPU), 60 is an automatic freeze control means,
Reference numeral 61 is an information storage means, 62 is an irradiation time setting means, 63 is an irradiation time measuring means, 64 is an automatic freeze means, and 70 is a display.

As shown in FIG. 1, the ultrasonic diagnostic apparatus of this embodiment has an ultrasonic probe 10 of the convex electronic scanning system, for example. The ultrasonic probe 10 is used by being brought into contact with the body surface of the subject 20 and irradiates the body of the subject 20 with an ultrasonic beam and scans the ultrasonic beam in a fan shape. It is designed to let you.

Irradiation and scanning of the ultrasonic beam are performed by the ultrasonic wave transmitting / receiving means 30.

Further, the ultrasonic wave transmitting / receiving means 30 receives, via the ultrasonic probe 10, the reflection echoes reflected by the boundaries of the ultrasonic beam in the body where the acoustic impedances are different.

That is, the ultrasonic wave transmitting / receiving means 30 is
A pulser for forming the ultrasonic beam, a transmission delay means, and converting the reflected echo into an electric signal,
It is composed of an amplifier for amplifying the electric signal.

The received signal corresponding to the reflected echo from the ultrasonic wave transmitting / receiving means 30 is signal processing means 4
Input to 0.

The signal processing means 40 is means for converting the received signal into a video signal. For example, a reception delay / addition means for aligning and adding the phases of the received signals, and a gain control for sensitivity adjustment. LOG for which an optimum compression ratio is set by the relationship between the means and the display device 70 described later.
It is composed of an amplifier / dynamic range setting means and a full-wave rectification / envelope means for removing a carrier component (high frequency) of a received signal.

The video signal output from the signal processing means 40 is converted into a digital signal via the A / D converter 51 and then input to the scan converter 52.

The scan converter 52 includes a line memory for sequentially writing a video signal corresponding to one scanning direction of the ultrasonic beam for each scanning direction, and a video signal from the line memory for sequentially writing an image for one field. It is composed of an image memory for storing information.

The output from the scan converter 52 is converted into a video signal again via the D / A converter 53 and then output to the display 70.
A tomographic image of the subject 20 in a plane scanned by the ultrasonic beam is displayed.

The processing / control means 50 comprises a central processing unit (CPU) 54 and an automatic freeze control means 60. The automatic freeze control means 60 includes an information storage means 61,
An irradiation time setting means 62, an irradiation time measuring means 63, and an automatic freeze means 64 are provided.

The central processing unit (CPU) 54 is shown in FIG.
1, the ultrasonic wave transmitting / receiving means 30 shown in FIG.
The scan converter 52, the information storage means 61, and the irradiation time measuring means 63 are controlled.

That is, the central processing unit (CPU) 54
Controls the ultrasonic transmission / reception means 30 so that the same operation is performed each time each scanning of the ultrasonic beam in the ultrasonic probe 10 is repeated (in other words, for each field).

A signal for stopping the irradiation of the ultrasonic beam is sent to the ultrasonic wave transmitting / receiving means 30 under a certain condition determined by the automatic freeze control means 60.

The automatic freeze control means 60 is as follows.
An information storage means 61 is provided, and the information storage means 61 stores each information at the stage of the current operation by the output from the central processing unit (CPU) 54.

The specific contents of the ultrasonic power information table 80 are, as shown in FIG. 3, an inspection mode, a probe shape, a probe frequency, and a transmission wave which can be changed by operating panel and menu settings. The information includes focus, pulse repetition frequency, ultrasonic output setting power setting, and the like.

For example, the inspection mode includes B mode, M mode, Doppler mode, and color Doppler mode, and the probe shape includes linear, convex, and electronic sector types. The frequency of the probe is 2.5 MHz, 3.5 MHz, 5 MHz, 7.5 M
There are types of Hz, and as the transmission focus, F1, F
There are two types, F3, F4, F5, F6, F7, and F8. The pulse repetition frequency is 1 kHz, 2
kHz, 3 kHz, 4 kHz, 5 kHz, 6 kHz
z, 8kHz, 10kHz, 16kHz,
The ultrasonic output setting power setting is 100%, 80
%, 60%, 40%, 20% (see FIG. 3).

Here, the ultrasonic power information table 8
The calculation of an index TI (Thermal Index) relating to the temperature rise inside the living body, which is a factor that directly reflects the adverse effect of ultrasonic waves on the living body from each information of 0, will be described.

Regarding this index TI, for example, "Diagnostic ultrasound: bioeffect and safty, C.
RBMerritt, FWKremkau and JCHobbins, Ultrasound
Obstet. Gynecol, 2 (1992) pp 366-374 ”.

According to this document, there is the relationship shown in equation 1 between the ultrasonic wave irradiation time t that affects the living body and the index TI. When the index TI is set to the reference (0), the table shown in FIG. 4 is obtained.

[0036]

T = 4 ^{(6-TI) In the} chart shown in FIG. 4, for example, TI is “+4.
In the case where the ultrasonic power of 0 ”(the temperature inside the living body is 41 ° C.) is being irradiated, it means that if the irradiation is continued for 16 minutes or more, the living body may be affected. That is, it is possible to know the limit value of the irradiation time of the predetermined ultrasonic power from the chart shown in FIG.

That is, the information storage means 61 stores the ultrasonic power information table 80 and the index TI relating to the temperature rise.

Here, the state of the ultrasonic power information table 80 when the index TI is determined will be described. Information storage means (ultrasonic power information storage circuit) 61
Stores TI values measured in advance for all combinations of parameter values of the ultrasonic power information table 80 set by the operation panel.

FIG. 5 shows a setting example of the state of the information table when the index TI is determined in this embodiment. When there is a clear correlation (proportional relationship in the case of ultrasonic output power setting) with respect to some parameter values such as ultrasonic output power setting, calculation is performed using the CPU 54 inside the ultrasonic device. May be.

FIGS. 6A, 6B and 6C are examples showing the relationship between the index TI and the irradiation time t which affects the living body.

The irradiation time t is set by the irradiation time setting means 62. For example, the irradiation time t that affects the living body is selected and set from the chart shown in FIG. In this case, the irradiation time t may be set from the chart shown in FIG. 6 (b), and an upper limit may be set for the set time as shown in FIG. 6 (c).

In this way, the irradiation time t affecting the living body is set and output from the irradiation time setting means 62. The irradiation time measuring means 63 comprises a counter that measures the elapsed time from the start of ultrasonic wave irradiation.

Then, the data of the irradiation time t affecting the living body from the irradiation time setting means 62 is inputted to the automatic freeze means 64, while the elapsed time from the start of the irradiation of ultrasonic waves (ultrasonic wave irradiation time). Data corresponding to the measured time from the irradiation time measuring means 63 to be measured is input.

In the automatic freeze means 64, by comparing the data from the irradiation time setting means 62 with the data from the irradiation time measuring means 63, the measured ultrasonic irradiation time is set. When it exceeds, the signal to that effect is sent to the CPU 54.

Thereafter, the CPU 54 controls the ultrasonic wave transmitting / receiving means 3
A signal for stopping ultrasonic wave irradiation is transmitted to 0.

Next, the operation of the ultrasonic diagnostic apparatus of this embodiment will be described with reference to FIGS. 1 and 2 (flowchart for explaining the operation of the automatic freeze control). Since the normal operation of the ultrasonic diagnostic apparatus of this embodiment is the same as the conventional operation, the description of the operation will be omitted here and only the operation of the automatic freeze control will be described.

In FIG. 1, the ultrasonic irradiation conditions such as the inspection mode are stored in the information storage means 61 via the CPU 54 by the information input means (not shown), and the ultrasonic power information table 80 is created. Based on the input ultrasonic wave irradiation condition, ultrasonic wave irradiation is started from the ultrasonic probe 10 via the ultrasonic wave transmitting / receiving means 30 (freezing cancellation).
(Step 201).

Next, the CPU 54 causes the information storage means 61 to be operated.
Ultrasonic irradiation conditions of the ultrasonic power information table 80 stored in, for example, as in setting example 2 shown in FIG. 5, the inspection mode is B mode, the probe shape is linear,
The probe frequency is 3.5 MHz, the transmission focus is F4, the pulse repetition frequency is 4 kHz, and the ultrasonic output power setting is 80%, and the ultrasonic power is calculated from the ultrasonic irradiation conditions. TI <0.5 is determined (step 202). The ultrasonic power corresponds to the index TI described above.

Next, the irradiation time setting means 62 stores the information in the information storage means 61, for example, as shown in FIG.
The irradiation time t (irradiable time Tr) affecting the living body corresponding to the calculated ultrasonic power (index TI) is selected and set from the chart shown in (a) (step 203). Data corresponding to the set irradiation available time Tr is input to the automatic freeze means 64.

On the other hand, the irradiation time measuring means (counter)
63 is reset (step 204). The irradiation time count number T at the time of this reset is set to “0” (T = 0),
The change time of the irradiation time is set to ΔT, and the irradiation time measurement means (counter) 63 starts the irradiation time measurement (step 205). Then, the elapsed time T ′ from the start of ultrasonic wave irradiation measured by the irradiation time measuring means (counter) 63 is input to the automatic freeze means 64.

In the automatic freeze means 64, it is judged (compared) whether the elapsed time T'exceeds the irradiation possible time Tr (step 206). In this determination,
When the elapsed time T ′ does not exceed the irradiation possible time Tr, the elapsed time T ′ is set to T and the process returns to step 205 (step 207). The processing of this loop is repeated until the elapsed time T ′ exceeds the irradiation possible time Tr. That is, the measurement of the elapsed time is continued.

Then, the elapsed time T'is the irradiation possible time Tr
If it exceeds, the automatic freeze means 64 sends an automatic freeze signal to the CPU 54 (step 208).

As a result, the CPU 54 sends a signal for stopping ultrasonic wave irradiation to the ultrasonic wave transmitting / receiving means 30.

As can be seen from the above description, according to the ultrasonic diagnostic apparatus of this embodiment, the information storage means 61 is provided, and the information storage means 61 reflects the temperature rise in the living body by the irradiation of ultrasonic waves. A condition table (see FIG. 2) is stored. Then, the allowable value of the ultrasonic wave irradiation time is selected and set from the information of the ultrasonic power information table 80 stored in the information storage means 61 from the conditions of the ultrasonic wave irradiation, while the irradiation time measuring means 63 is used. It is determined whether or not the elapsed time from the start of ultrasonic wave irradiation (ultrasonic wave irradiation time) to be measured is larger than the allowable value of the set ultrasonic wave irradiation time, and the ultrasonic wave irradiation time is longer than the allowable value. By automatically driving the freezing means 64 to stop the ultrasonic irradiation when the size becomes large, the ultrasonic diagnostic layer itself automatically controls the irradiation time regardless of the ultrasonic power applied in each inspection mode. Therefore, it is possible to use an ultrasonic wave having an ultrasonic power or less that does not affect the subject. Moreover, since the operator can be alerted, the ultrasonic diagnostic apparatus can be used extremely safely.

Although the present invention has been specifically described based on the embodiments, it is needless to say that the present invention is not limited to the above embodiments and various modifications can be made without departing from the scope of the invention. .

[0056]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) No matter what ultrasonic power is applied in each examination mode, the ultrasonic diagnostic layer itself automatically controls the irradiation time. The following ultrasonic waves can be used.

(2) Since the operator can be alerted,
The ultrasonic diagnostic apparatus can be used extremely safely.

[Brief description of drawings]

FIG. 1 is a block configuration diagram showing a schematic configuration of an embodiment of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is a flowchart for explaining the operation of the automatic freeze control means in the ultrasonic diagnostic apparatus of this embodiment.

FIG. 3 is a table showing specific contents of an ultrasonic power information table in the ultrasonic diagnostic apparatus of this embodiment.

FIG. 4 is a diagram showing a table showing a relationship between an ultrasonic wave irradiation time t affecting a living body and an index TI in the ultrasonic diagnostic apparatus of this embodiment.

FIG. 5 is a chart showing a setting example of the state of the information table when the index TI is determined in the ultrasonic diagnostic apparatus of this embodiment.

FIG. 6 is a diagram showing an example of a chart showing a relationship between an ultrasonic wave irradiation time t affecting a living body and an index TI in the ultrasonic diagnostic apparatus of the present embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Ultrasonic probe, 20 ... Examinee, 30 ... Ultrasonic wave transmission / reception means, 40 ... Signal processing means, 50 ... Processing / control means,
51 ... A / D converter, 52 ... Scan converter, 53
... D / A converter, 54 ... Central processing unit (CPU), 60
... Automatic freeze control means, 61 ... Information storage means, 62 ...
Irradiation time setting means, 63 ... Irradiation time measuring means, 64 ... Automatic freeze means, 70 ... Display device.

Claims (1)

[Claims] 1. An information storage unit for storing condition information reflecting a temperature rise in a living body by ultrasonic irradiation, and an irradiation time setting unit for setting a permissible value of ultrasonic irradiation time by an output from the information storage unit. An irradiation time measuring means for measuring an elapsed time from the start of ultrasonic irradiation, and an automatic stop of the ultrasonic irradiation when the measured elapsed time from the start of ultrasonic irradiation exceeds the preset allowable value. An ultrasonic diagnostic apparatus comprising: freeze means.