JP3927858B2 - Ultrasonic diagnostic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to temperature management of an array transducer (or ultrasonic probe).
[0002]
[Prior art and problems]
In general, an ultrasonic probe (probe) has an array transducer including a plurality of vibration elements. An ultrasonic beam is formed by the array transducer, and the ultrasonic beam is electronically scanned. Examples of the electronic scanning method include electronic linear scanning and electronic sector scanning.
[0003]
In any case, a high-voltage transmission drive signal is supplied to each of the plurality of vibration elements, whereby ultrasonic waves are transmitted for each vibration element. The power loss in the electroacoustic conversion generates heat. That is, the array transducer generates heat, and the heat is conducted to each part of the ultrasonic probe. Due to the heat conduction, the surface of the acoustic lens also becomes hot. For this reason, from the viewpoint of safety with respect to a living body, temperature management of the array transducer or the ultrasonic probe is very important (there are laws and regulations, safety standards, etc.).
[0004]
Some conventional ultrasonic diagnostic apparatuses perform temperature management by monitoring the voltage and current of a shared transmission power source, that is, by monitoring the total power related to transmission. In addition, when the number of transmission pulses (wave number) increases, the voltage of the transmission power supply is lowered.
[0005]
However, in the past, since the entire array transducer was macroscopically evaluated and uniform power limitation was performed, more strict management could not be performed, and in some cases excessive power limitation was performed. There is a case. In the latter case, there is a problem that sensitivity is lowered.
[0006]
Here, on the premise of electronic linear scanning, the temperature distribution along the element arrangement direction in the array transducer will be examined. For example, in a color flow mapping mode in which a two-dimensional color blood flow image (color Doppler image) is synthesized and displayed on a two-dimensional black-and-white tomographic image (B mode image), one transmission is performed for the B mode per beam address. For example, transmission for color Doppler needs to be performed 10 times (transmission conditions are different). In addition, there are many cases where a region for forming a color Doppler image is set to a part. In this case, the temperature at each position in the array transducer is not uniform, and the temperature in the range where transmission for color Doppler is performed is further increased. Therefore, if the temperature is uniformly evaluated, it is mistaken locally.
[0007]
On the other hand, there is a method to calculate the temperature by software calculation considering the transmission conditions, but in response to various condition settings such as resolution priority and sensitivity priority, the voltage, wave number, transmission interval etc. of the transmission pulse are finely adjusted, Also, since the operation sequence is complicated, the amount of calculation is enormous and the calculation content is complicated.
[0008]
An object of the present invention is to enable local temperature monitoring of an array transducer.
[0009]
Another object of the present invention is to enable local temperature control of an array transducer.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is provided with an array transducer in which a plurality of representative vibration elements are set discretely , a transmission power source, and a voltage from the transmission power source. A plurality of transmission circuits that excite transmission pulses and output transmission drive signals to the plurality of vibration elements ; and a plurality of transmission units corresponding to the plurality of representative vibration elements in the plurality of transmission circuits. A plurality of transmission power detection circuits provided for the representative transmission circuit, and a temperature monitoring control unit that performs temperature management based on detection results from the plurality of transmission power detection circuits, and the array transducer In contrast, local temperature management can be performed.
[0011]
According to the above configuration, the plurality of transmission power detection circuits are provided for the plurality of representative vibration elements discretely set in the array vibrator, and thereby the temperature or temperature rise at each position of the array vibrator is provided. It is possible to estimate. That is, local temperature evaluation can be performed. It is also possible to perform temperature monitoring with respect to the vibration element of the representative from among all of the vibration element. When electronic linear scanning or the like is employed, it is desirable to set the interval between representative vibration elements to be monitored in consideration of the size of the transmission aperture. According to the configuration, the temperature can be finely controlled while suppressing an increase in circuit scale.
[0013]
Preferably, each transmission power detection circuit detects transmission power with reference to a power supply voltage of the transmission power supply or a voltage weighted to the power supply voltage and the transmission pulse. Since the transmission condition is reflected in the transmission pulse, if the transmission pulse itself is used as a reference in addition to the transmission voltage, the transmission power can be accurately obtained in consideration of the transmission condition at that time.
[0014]
Preferably, the transmission power is detected at regular intervals. Preferably, the certain period corresponds to one frame. Considering the average transmission power per unit time, both heat generation and heat dissipation can be considered.
[0015]
Preferably, the temperature monitoring control unit limits transmission power for all of the plurality of vibration elements when there is at least one excess detection result that exceeds a determination value among detection results of the plurality of transmission power detection circuits. Execute control.
[0016]
Preferably, the temperature monitoring control unit responds to the excess detection result among the plurality of vibration elements when there is an excess detection result that exceeds a determination value among the detection results of the plurality of transmission power detection circuits. Control for limiting the transmission power is executed for some vibration elements. According to this configuration, fine temperature management can be performed.
[0017]
Moreover, the restriction of the transmission power, reduction of the pulse number, increase in transmission repetition period, a voltage drop of the transmission driving signals, and, 1 also include at least one of reducing the number of transmissions per beam address Good .
[0018]
Preferably, the present invention corresponds to an array transducer including a plurality of transducer elements, a transmission unit that outputs a transmission drive signal to the plurality of transducer elements, and all or part of the plurality of transducer elements. A plurality of transmission power detection circuits provided, and a temperature monitoring control unit that performs temperature management based on detection results from the plurality of transmission power detection circuits, wherein the temperature monitoring control unit includes the plurality of transmission powers When there is at least one excess detection result exceeding the determination value among the detection results of the detection circuit, control is performed to limit transmission power for all of the plurality of vibration elements, and the temperature management control unit in combined mode where transmission and reception for the first mode and send and receive for the second mode is executed each time, to limit its transmit power with respect to reception of the second mode, the array transducer To perform local temperature management, the first mode is a mode for two-dimensional tomographic imaging, the second mode is a mode for two-dimensional bloodstream image formed. In addition, the present invention is provided corresponding to all or part of the plurality of vibration elements, an array vibrator including a plurality of vibration elements, a transmission unit that outputs a transmission drive signal to the plurality of vibration elements, and A plurality of transmission power detection circuits, and a temperature monitoring control unit that performs temperature management based on detection results from the plurality of transmission power detection circuits, and the temperature monitoring control unit includes the plurality of transmission power detections. When there is an excess detection result that exceeds a determination value among the detection results of the circuit, control is performed to limit transmission power for a part of the vibration elements corresponding to the excess detection result among the plurality of vibration elements, In the combined mode in which transmission / reception for the first mode and transmission / reception for the second mode are executed for each beam direction, the temperature management control unit limits transmission power only for transmission / reception of the second mode. Local temperature management is performed on the array transducer, the first mode is a mode for forming a two-dimensional tomographic image, and the second mode is a mode for forming a two-dimensional blood flow image. And
[0019]
In order to achieve the above object, the present invention provides an array transducer including a plurality of vibration elements, a plurality of transmission circuits that output transmission drive signals to the plurality of vibration elements, and the plurality of vibration elements. And a plurality of power detection circuits that are provided for a plurality of representative vibration elements that are discretely set and detect power for a transmission drive signal output to each representative vibration element, and the plurality of power detection circuits And a temperature monitoring control unit that performs temperature management for each local portion of the array transducer based on the detection result.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0021]
FIG. 1 is a block diagram showing the configuration of the transmission unit of the ultrasonic diagnostic apparatus according to the present invention.
[0022]
The array transducer 10 is provided in an ultrasonic probe (not shown). The array transducer 10 includes a plurality of transducer elements 12, and an ultrasonic beam is formed by the array transducer 10. The ultrasonic beam is scanned electronically, for example. The ultrasonic probe may be used in contact with the body surface or may be used by being inserted into a body cavity.
[0023]
The transmission control circuit 14 controls the operation of the transmission circuit 18 provided for each vibration element 12. Specifically, transmission pulses are supplied to each transmission circuit 18 with a predetermined delay relationship. The operation of the transmission control circuit 14 is controlled by a host controller (not shown), and necessary signals such as a frame synchronization signal are input to the transmission control circuit 14. The transmission circuit group 16 includes a plurality of transmission circuits 18 in the present embodiment. The transmission circuit 18 inputs a transmission pulse and outputs a transmission drive signal excited with respect to the corresponding vibration element.
[0024]
A reception signal from each vibration element 12 is input to the reception unit 20. Then, the receiving unit 20 performs a phasing addition process on the plurality of received signals.
[0025]
In the present embodiment, in order to monitor the temperature of a plurality of representative vibration elements that are representative among the plurality of vibration elements 12, a plurality of detection circuits are provided for a plurality of representative transmission circuits corresponding to the representative vibrators. 24 is connected. These detection circuits 24 constitute a detection circuit group 22.
[0026]
Each detection circuit 24 is a circuit that obtains predetermined information from a transmission circuit connected thereto and detects transmission power (transmission power). Of course, as long as the temperature can be monitored, other physical information may be detected.
[0027]
The temperature monitoring control circuit 26 performs necessary operation control on the transmission control circuit 14 based on detection results output from the plurality of detection circuits 24, that is, transmission power information. Further, control information may be sent from the temperature monitoring control circuit 26 to the host controller.
[0028]
In any case, the temperature monitoring control circuit 26 compares the transmission power information output from each detection circuit 24 with a predetermined determination value, and if the transmission power value exceeds the determination value, the temperature monitoring control circuit 26 Determine the need for restrictions. When such a determination is made, the temperature monitoring control circuit 26 controls the transmission control circuit 14 so that the transmission power is limited for all the vibration elements 12 or a part of the vibration elements 12. Command.
[0029]
In this case, the transmission power is limited locally only for the vibration element whose temperature rise is estimated, specifically, for the surrounding vibration element group including the representative element whose temperature rise is determined. You may be made to be.
[0030]
For limiting the transmission power, various methods such as a reduction in the number of transmission pulses, a decrease in transmission voltage, and a variable control for extending the transmission repetition period can be used.
[0031]
FIG. 2 shows the relationship between the array transducer 10 and the transmission aperture 100. For example, if the minimum transmission aperture is as shown in FIG. 2, a plurality of discrete transmissions, i.e., at regular intervals, are present so that there is at least one representative vibration element in the minimum transmission aperture. A representative vibration element may be set. In FIG. 2, the vibration elements # 0, # 8, # 16,... Are selected as representative vibration elements for temperature monitoring. Of course, in order to perform temperature monitoring more finely, a detection circuit may be provided for the vibration elements of all channels.
[0032]
FIG. 3 is a block diagram showing the principle of transmission power detection.
[0033]
As described above, the transmission pulse is supplied to the transmission circuit 18, and the transmission pulse is specifically used as an input trigger for the switching circuit 34. A transmission power supply 30 is connected to the switching circuit 34 via a weighting circuit 32, that is, a voltage from the transmission power supply 30 is applied to the switching circuit 34. Here, the weighting circuit 32 functions when, for example, the voltage is weighted according to the position in the transmission aperture, and the transmission control circuit 14 shown in FIG. 1 adjusts the weighting amount. When the transmission pulse is input, the switching circuit 34 excites the transmission pulse as a trigger. As a result, a high voltage transmission drive signal is output to the corresponding vibration element.
[0034]
On the other hand, the voltage of the transmission power supply 30 or the weighted voltage is applied to the detection circuit 24. A transmission pulse is input to the detection circuit 24, and the detection circuit 24 obtains transmission power from the voltage of the transmission power supply and the transmission pulse. In this case, a capacitor that charges the power from the transmission power supply 30 using the transmission pulse as a switching signal may be used, and the transmission power, that is, the transmission power may be obtained from the amount of charge per unit time accumulated in the capacitor. In this case, such a capacitor is reset every predetermined period, and in that case, a frame synchronization signal can be used as a reset signal. That is, the average transmission power is obtained for each frame.
[0035]
For example, in the color flow mapping mode in which a color Doppler image is synthesized on a B mode image, when transmission power is limited, transmission for B mode is executed as it is, and the wave number of transmission for one color Doppler is performed. The transmission voltage may be changed. Of course, the transmission power may be reduced for each transmission in the two modes.
[0036]
【The invention's effect】
As described above, according to the present invention, local temperature monitoring can be performed on the array transducer. Further, by controlling the temperature of the local array transducer, safety for a living body can be achieved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a transmission unit of an ultrasonic diagnostic apparatus according to the present invention.
FIG. 2 is a diagram illustrating a relationship between an array transducer and a transmission aperture.
FIG. 3 is a diagram for explaining transmission power detection;
[Explanation of symbols]
10 array transducer, 12 transducer, 14 transmission control circuit, 18 transmission circuit, 24 detection circuit, 26 temperature monitoring control circuit.

Claims (7)

An array transducer that includes a plurality of vibration elements and in which a plurality of representative vibration elements are set discretely ;
A transmission unit having a transmission power source and a plurality of transmission circuits that are supplied with a voltage from the transmission power source and excite a transmission pulse to output a transmission drive signal to the plurality of vibration elements;
A plurality of transmission power detection circuits provided for a plurality of representative transmission circuits corresponding to the plurality of representative vibration elements in the plurality of transmission circuits ;
A temperature monitoring controller that performs temperature management based on detection results from the plurality of transmission power detection circuits;
Including
An ultrasonic diagnostic apparatus characterized in that local temperature management can be performed on the array transducer. The apparatus of claim 1 .
Each of the transmission power detection circuits detects transmission power with reference to a power supply voltage of the transmission power supply or a voltage weighted with respect to the power supply voltage, and the transmission pulse. apparatus. The apparatus of claim 2 .
The ultrasonic diagnostic apparatus, wherein the transmission power is detected at regular intervals. The apparatus of claim 3 .
The ultrasonic diagnostic apparatus according to claim 1, wherein the predetermined period corresponds to one frame. An array vibrator comprising a plurality of vibration elements;
A transmission unit that outputs a transmission drive signal to the plurality of vibration elements;
A plurality of transmission power detection circuits provided corresponding to all or a part of the plurality of vibration elements;
A temperature monitoring controller that performs temperature management based on detection results from the plurality of transmission power detection circuits;
Including
The temperature monitoring control unit executes control for limiting transmission power for all of the plurality of vibration elements when there is at least one excess detection result exceeding a determination value among detection results of the plurality of transmission power detection circuits. And
In the combined mode in which transmission and reception for the first mode and transmission and reception for the second mode are executed for each beam direction, the temperature management control unit limits transmission power only for transmission and reception of the second mode, Perform local temperature management for the array transducer,
The ultrasonic diagnostic apparatus, wherein the first mode is a mode for forming a two-dimensional tomographic image, and the second mode is a mode for forming a two-dimensional blood flow image . An array vibrator comprising a plurality of vibration elements;
A transmission unit that outputs a transmission drive signal to the plurality of vibration elements;
A plurality of transmission power detection circuits provided corresponding to all or a part of the plurality of vibration elements;
A temperature monitoring controller that performs temperature management based on detection results from the plurality of transmission power detection circuits;
Including
When there is an excess detection result that exceeds a determination value among the detection results of the plurality of transmission power detection circuits, the temperature monitoring control unit is configured to select a part of the plurality of vibration elements corresponding to the excess detection result. Executes control to limit the transmission power for the vibration element,
In the combined mode in which transmission and reception for the first mode and transmission and reception for the second mode are executed for each beam direction, the temperature management control unit limits transmission power only for transmission and reception of the second mode, Perform local temperature management for the array transducer,
The ultrasonic diagnostic apparatus, wherein the first mode is a mode for forming a two-dimensional tomographic image, and the second mode is a mode for forming a two-dimensional blood flow image . An array vibrator comprising a plurality of vibration elements;
A plurality of transmission circuits that output transmission drive signals to the plurality of vibration elements;
A plurality of power detection circuits which are provided for a plurality of representative vibration elements set discretely among the plurality of vibration elements, and which detect power for a transmission drive signal output to each representative vibration element;
Based on detection results from the plurality of power detection circuits, a temperature monitoring control unit that performs temperature management for each local portion of the array transducer, and
An ultrasonic diagnostic apparatus comprising:

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