JP2012187187A - Ultrasound diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasound diagnostic apparatus enabling consistent ultrasound diagnosis against heat generated in an integrated circuit board or the like of an ultrasound probe.SOLUTION: The ultrasound probe transmits and receives ultrasonic waves in different directions and the diagnostic apparatus body combines a plurality of images captured in the different directions of transmission and reception to produce an ultrasound image. In this process, the ultrasound diagnostic apparatus measures the temperature of the ultrasound probe to reduce the number of times of ultrasound transmission and reception, more specifically, the number of images to be combined in accordance with a temperature measurement result.

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that can suppress heat generation of an ultrasonic probe.

In the medical field, an ultrasonic diagnostic apparatus using an ultrasonic image has been put into practical use.
In general, this type of ultrasonic diagnostic apparatus includes an ultrasonic probe (hereinafter referred to as a probe) and a diagnostic apparatus main body, and transmits ultrasonic waves from the probe toward a subject. The ultrasonic echo from the subject is received by the probe, and the received signal is electrically processed by the diagnostic apparatus body to generate an ultrasonic image.

  In such an ultrasonic diagnostic apparatus, so-called speckle (speckle noise / speckle pattern) is known as a factor that degrades the image quality of an ultrasonic image. Speckle is white point-like noise that is generated when scattered waves are generated by innumerable scattering sources smaller than the wavelength of ultrasonic waves existing in the subject and the scattered waves interfere with each other.

As a method for reducing such speckle in an ultrasonic diagnostic apparatus, a spatial compound as disclosed in Patent Literature 1 and Patent Literature 2 is known.
As conceptually shown in FIG. 6, the spatial compound transmits and receives a plurality of types (multiple directions) of ultrasonic waves having different directions (scanning angles) from the piezoelectric element unit 100 to the subject. This is a technique for generating a single synthesized ultrasound image by synthesizing a plurality of ultrasound images obtained by different types of transmission / reception.

Specifically, in the example shown in FIG. 6, transmission / reception of ultrasonic waves (normal transmission / reception) similar to generation of a normal ultrasonic image, transmission / reception of ultrasonic waves in a direction inclined by θ with respect to normal, and Three types (three directions) of ultrasonic transmission / reception are performed, that is, transmission / reception of ultrasonic waves in a direction inclined by −θ with respect to a normal angle.
The ultrasonic image A (solid line) obtained by the normal transmission / reception, the ultrasonic image B (broken line) obtained by the transmission / reception with the angle inclined by θ, and the ultrasonic image obtained by the transmission / reception with the angle inclined by −θ. By combining C (one-dot chain line), a combined ultrasonic image of the region of the ultrasonic image A indicated by the solid line is generated.

By the way, a probe constituting such an ultrasonic diagnostic apparatus transmits an ultrasonic wave to a subject, receives an ultrasonic echo reflected by the subject, and outputs it as an electrical signal (received signal). It has an element unit.
Further, in recent years, the probe is based on amplification of received signals output from the piezoelectric element unit, A / D conversion and processing, switching of transmission / reception timing of ultrasonic waves in the piezoelectric element unit, and wireless communication with the diagnostic apparatus body. In some cases, an integrated circuit board or the like is mounted for cordless operation or noise reduction.

As is well known, the piezoelectric element unit generates heat by transmitting and receiving ultrasonic waves. In addition, the higher the output of the ultrasonic wave transmitted by the piezoelectric element unit, the higher the quality of the ultrasonic image is obtained. On the other hand, the amount of heat generated by the piezoelectric element unit also increases.
Further, the integrated circuit board also generates heat by processing received signals and the like.

When the probe generates heat, the driving of the pressure line element unit becomes unstable, and the operation of each circuit of the integrated circuit board becomes unstable. As a result, the output signal for the transmitted ultrasonic wave and the received ultrasonic wave becomes unstable, and further, the signal processing in the integrated circuit board becomes unstable, and the image quality of the ultrasonic image is degraded.
Therefore, in order to stably obtain a high-quality ultrasonic image, the ultrasonic diagnostic apparatus needs to suppress the temperature rise inside the probe as much as possible.

JP 2005-58321 A JP 2003-70786 A

  An object of the present invention is to solve the above-described problems of the prior art, and suppresses a temperature rise in an ultrasonic probe when generating an ultrasonic image (synthetic ultrasonic image) by a spatial compound, An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of minimizing image quality degradation of an ultrasonic image even when the temperature rises.

  In order to achieve the above object, an ultrasonic diagnostic apparatus of the present invention transmits an ultrasonic wave, receives an ultrasonic echo reflected by a subject, and outputs a received signal corresponding to the received ultrasonic wave. A unit, a transmission control unit that controls transmission of ultrasonic waves by the piezoelectric element unit, a signal processing unit that processes a received signal output from the piezoelectric element unit, and a temperature measuring unit that measures a temperature at a predetermined position An ultrasonic probe and a diagnostic device main body that generates an ultrasonic image according to the received signal processed by the signal processing means of the ultrasonic probe, and the diagnostic device main body synthesizes a predetermined number of the ultrasonic images. The ultrasonic probe has a function of generating one synthetic ultrasonic image, and the ultrasonic probe transmits and receives ultrasonic waves so that the diagnostic apparatus main body generates a synthetic ultrasonic image. The ultrasonic probe has a function of transmitting and receiving a plurality of types of ultrasonic waves having the same number as the predetermined number different from each other, and the ultrasonic probe has the temperature when the diagnostic apparatus main body generates a synthesized ultrasonic image. An ultrasonic diagnostic apparatus characterized in that, according to a temperature measurement result by a measuring means, transmission / reception of ultrasonic waves for generating a synthetic ultrasonic image is one or more types obtained by subtracting zero or more types from the plurality of types. provide.

In such an ultrasonic diagnostic apparatus of the present invention, it is preferable that the temperature measuring unit measures the temperature of the signal processing unit.
Further, when the diagnostic apparatus main body generates a synthetic ultrasound image, the ultrasound probe includes at least one type of ultrasound transmission / reception including an entire area to be output as the synthesized ultrasound image. It is preferable to perform transmission / reception of ultrasonic waves that can be obtained.

  Further, as a threshold value, a temperature T1 and a temperature T2 higher than the temperature T1 are set, and when the diagnostic apparatus main body generates a synthesized ultrasonic image, the ultrasonic probe is used as the temperature measuring unit. When the temperature measurement result is less than the temperature T1, the plurality of types of ultrasonic waves are transmitted and received, and when the temperature measurement result is equal to or higher than the temperature T2, the temperature measurement result is set. The minimum number of types of ultrasonic waves are transmitted and received, and when the temperature measurement result is not less than the temperature T1 and less than the temperature T2, the number of types of ultrasonic waves between the plurality of types and the minimum number is transmitted and received. preferable.

Further, as a threshold value, a temperature T1 and a temperature T2 higher than the temperature T1 are set, and when the diagnostic apparatus main body generates a synthesized ultrasonic image, the ultrasonic probe is used as the temperature measuring unit. When the temperature measurement result is less than the temperature T1, the plurality of types of ultrasonic waves are transmitted and received. When the temperature measurement result is equal to or higher than the temperature T1, the temperature measurement result is continuously in time. In the two synthesized ultrasonic images, at least one of the plurality of types is preferably reduced by one or more types, and the number of types of ultrasonic waves that are different from the number of the plurality of types is preferably transmitted and received.
In addition, when the temperature measurement result is equal to or higher than the temperature T1 and lower than the temperature T2, the ultrasonic wave obtained by subtracting one or more types from the plurality of types in one of the two continuous ultrasonic images continuous in time. It is preferable to perform transmission / reception.
Further, when the temperature measurement result is equal to or higher than T2, ultrasonic waves obtained by subtracting one or more types from the plurality of types are transmitted and received in both images of the two or less ultrasonic synthesized images that are continuous in time. Is preferred.

Moreover, it is preferable that the ultrasonic probe equalizes the ultrasonic transmission / reception direction of the closest ultrasonic image in the temporally continuous synthetic ultrasonic image.
In addition, when the diagnostic apparatus main body generates a synthetic ultrasound image, the ultrasound probe may reduce the transmission / reception of two or more types of ultrasonic waves from the plurality of types, and the synthesized ultrasound image that is temporally continuous. In the sound wave image, it is preferable to transmit and receive the ultrasonic wave so as to reduce the continuous ultrasonic image.
Furthermore, when the diagnostic apparatus main body generates a synthetic ultrasound image, the ultrasound probe is configured to continuously transmit the synthesized ultrasound images that are temporally continuous when reducing transmission / reception of one or more types of ultrasound from the plurality of types. In the sound wave image, it is preferable to transmit and receive the ultrasonic wave so as to reduce the adjacent ultrasonic image.

The ultrasonic diagnostic apparatus of the present invention having the above configuration reduces the number of images to be combined according to the temperature rise in the ultrasonic probe when performing spatial compounding to combine a plurality of images having different ultrasonic transmission / reception directions. To do.
Therefore, in the present invention, when performing spatial compounding, the driving frequency of an integrated circuit, a piezoelectric element unit, and the like mounted on the ultrasonic probe can be reduced according to the temperature in the ultrasonic probe. Therefore, when heat is generated in the ultrasonic probe, these temperature rises can be suppressed. In addition, when the ultrasonic probe generates heat, the generation of heat can be suppressed and deterioration in image quality can be minimized.
Therefore, according to the ultrasonic diagnostic apparatus of the present invention, high-quality ultrasonic images can be stably obtained by spatial compounding.

1 is a block diagram conceptually showing an ultrasonic diagnostic apparatus of the present invention. It is a conceptual diagram for demonstrating the space compound performed with the ultrasonic diagnosing device shown in FIG. (A)-(C) are the conceptual diagrams for demonstrating the space compound in the ultrasonic diagnosing device shown in FIG. (A)-(C) are the conceptual diagrams for demonstrating another example of the spatial compound performed with the ultrasonic diagnosing device of this invention. (A) And (B) is a conceptual diagram for demonstrating another example of the spatial compound performed with the ultrasonic diagnosing device of this invention. It is a conceptual diagram for demonstrating a space compound.

  Hereinafter, the ultrasonic diagnostic apparatus of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a block diagram conceptually showing an example of the ultrasonic diagnostic apparatus of the present invention.
An ultrasonic diagnostic apparatus 10 illustrated in FIG. 1 includes an ultrasonic probe (ultrasonic probe) 12 and a diagnostic apparatus main body 14 connected to the ultrasonic probe 12 through wireless communication.

The ultrasonic probe 12 (hereinafter referred to as the probe 12) transmits an ultrasonic wave to the subject, receives an ultrasonic echo reflected by the subject, and generates an ultrasonic image number corresponding to the received ultrasonic echo. Output.
In the present invention, the type of the probe 12 is not particularly limited, and various types such as a convex type, a linear type, and a sector type can be used. Further, an extracorporeal probe or a probe for an ultrasonic endoscope such as a radial scan method may be used. Furthermore, the probe 12 may have an ultrasonic transducer for receiving harmonics of the second or higher order of the transmitted ultrasonic wave corresponding to harmonic imaging.

The probe 12 has a piezoelectric element unit 16 in which transducers 18 that transmit and receive ultrasonic waves (ultrasonic waves) are arranged one-dimensionally or two-dimensionally. The piezoelectric element unit 18 is connected to a signal processing unit 20 having an individual signal processing unit 20a.
The individual signal processing unit 20 a is connected corresponding to each transducer 18 of the piezoelectric element unit 16. In addition, a wireless communication unit 26 is connected to the individual signal processing unit 20 a via a parallel / serial conversion unit 24. Furthermore, an antenna 28 is connected to the wireless communication unit 26.
Each transducer 18 is connected to a transmission control unit 32 via a transmission drive unit 30, each individual signal processing unit 20 a is connected to a reception control unit 34, and a wireless communication unit 26 is connected to a communication control unit 36. ing. A probe controller 38 is connected to the parallel / serial converter 24, the transmission controller 32, the reception controller 34, and the communication controller 36.
Furthermore, in the ultrasonic diagnostic apparatus of the present invention, the probe 12 is provided with a temperature measuring means 42 for measuring the temperature of the signal processing unit 20. The temperature measurement result by the temperature measuring means 42 is supplied to the transmission control unit 32 and the reception control unit 34.

  The probe 12 incorporates a battery (not shown), and electric power for driving is supplied to each part from the battery.

  The piezoelectric element unit 16 transmits an ultrasonic wave to the subject, receives an ultrasonic echo reflected by the subject, and outputs a transducer 18 that outputs an electrical signal corresponding to the received ultrasonic echo in a one-dimensional or two-dimensional manner. It is a well-known one that is formed by stacking a backing layer, an acoustic matching layer, and an acoustic lens in a two-dimensional arrangement.

The transducer 18 is an ultrasonic transducer in which electrodes are formed on both ends of a piezoelectric body made of, for example, PZT (lead zirconate titanate) or PVDF (polyvinylidene fluoride).
When a pulsed or continuous wave voltage is applied to the electrodes of an ultrasonic transducer, the piezoelectric material expands and contracts, and pulsed or continuous wave ultrasonic waves are generated from the respective transducers. As a result, an ultrasonic beam is formed.
In addition, each transducer generates an electric signal by expanding and contracting by receiving propagating ultrasonic waves, and the electric signals are output as ultrasonic reception signals.

The transducer 18 transmits an ultrasonic wave according to the drive signal supplied from the transmission drive unit 30, receives an ultrasonic echo from the subject, converts it into an electrical signal (received signal), and converts it into an individual signal processing unit 20a. Output.
The transmission drive unit 30 includes a digital / analog converter, a low-pass filter, an amplifier, a pulser, and the like, and supplies a drive voltage to each transducer 18 (ultrasonic transducer) to vibrate the ultrasonic transducer. To transmit ultrasonic waves.
Further, the transmission driver 30 delays each drive signal so that the ultrasonic waves transmitted from the plurality of transducers 18 form an ultrasonic beam based on the transmission delay pattern selected by the transmission controller 32. Is supplied to a plurality of transducers 18.

An individual signal processing unit 20 a of the signal processing unit 20 is connected to each transducer 18 of the piezoelectric element unit 16.
The individual signal processing unit 20a has an AFE (Analog Front End) composed of an LNA (Low-Noise Amplifier), a VCA (Voltage-Controlled Attenuator), a PGA (Programmable Gain Amplifier), a low-pass filter, an analog / digital converter, and the like. Under the control of the reception control unit 34, the individual signal processing unit 20a processes the reception signal output from the corresponding transducer 18 by AFE and converts it into a digital reception signal. Further, the individual signal processing unit 20a generates a complex baseband signal by performing quadrature detection processing or quadrature sampling processing on the digital reception signal, and samples the complex baseband signal to thereby obtain information on the tissue area. Is generated, and the sample data is supplied to the parallel / serial converter 24.
The parallel / serial conversion unit 24 converts the parallel sample data generated by the individual signal processing unit 20a of a plurality of channels into serial sample data.

The probe 12 is provided with temperature measuring means 42 for measuring the temperature of the signal processing unit 20 (received signal processing circuit unit). The temperature measurement result of the signal processing unit 20 by the temperature measuring unit 42 is sent to the transmission control unit 32 and the reception control unit 34.
The temperature measuring means 42 is not particularly limited, and a known temperature measuring means can be used.
Further, the temperature measurement target by the temperature measuring means 20 is not limited to the signal processing unit 20, and may be within the probe 12. However, since the signal processor 20 (particularly AFE) that processes the received signal output from the transducer 18 generates the largest amount of heat in the probe 12, the temperature measuring means 20 measures the temperature by the signal processing. Part 20 is preferred.

Here, the ultrasonic diagnostic apparatus 10 has a function of performing spatial compounding, which generates a synthesized ultrasonic image by synthesizing a plurality of ultrasonic images obtained by transmitting and receiving ultrasonic waves having different directions. . As an example, the ultrasonic diagnostic apparatus 10 synthesizes three ultrasonic images in a spatial compound. Accordingly, when performing spatial compounding, the reception control unit 34 and the transmission control unit 32 have three types (three directions) of supertransmission / reception directions different from each other in accordance with the number of ultrasonic images to be combined. The drive of the transmission drive unit 30 and each individual signal processing unit 20a is controlled so as to transmit and receive sound waves.
Further, in the ultrasonic diagnostic apparatus 10, the number of images to be combined with the spatial compound is changed according to the temperature at a predetermined position in the probe 12. Specifically, the reception control unit 34 and the transmission control unit 32 change the number of ultrasonic images to be subjected to spatial compounding according to the temperature of the signal processing unit 20 measured by the temperature measurement unit 42. Change the number of send / receive types. This will be described in detail later.

The wireless communication unit 26 generates a transmission signal by modulating a carrier based on the serial sample data, and transmits the serial sample data by supplying the transmission signal to the antenna 28 and transmitting a radio wave from the antenna 28. .
As the modulation scheme, for example, ASK (Amplitude Shift Keying), PSK (Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (16 Quadrature Amplitude Modulation), and the like are used.
The wireless communication unit 26 performs wireless communication with the diagnostic device main body 14 to transmit sample data to the diagnostic device main body 14 and to receive various control signals from the diagnostic device main body 14. The control signal is output to the communication control unit 36. The communication control unit 36 controls the wireless communication unit 26 so that the sample data is transmitted with the transmission radio wave intensity set by the probe control unit 38 and also performs probe control on various control signals received by the wireless communication unit 26. To the unit 38.

The wireless communication unit 26 transmits sample data to the diagnostic device main body 14 and receives various control signals from the diagnostic device main body 14 by performing wireless communication with the diagnostic device main body 14 through the antenna 28. The received control signal is output to the communication control unit 36.
The communication control unit 36 controls the wireless communication unit 26 so that the sample data is transmitted with the transmission radio wave intensity set by the probe control unit 38 and also performs probe control on various control signals received by the wireless communication unit 26. To the unit 38.

  The probe control unit 38 controls each part of the probe 12 based on various control signals transmitted from the diagnostic apparatus main body 14.

As described above, the ultrasonic diagnostic apparatus 10 according to the present invention has a function of generating an image (synthetic ultrasonic image) based on a spatial compound.
As is well known, spatial compound refers to the transmission / reception of a plurality of types (multiple directions) of ultrasonic waves (hereinafter referred to as “transmission and reception”) in which the directions of transmission / reception of ultrasonic waves (scanning angle / scanning direction) are different from each other. This is a technique for generating one synthesized ultrasound image by synthesizing ultrasound images obtained by the plurality of types of transmission / reception. By performing such spatial compounding, speckle can be reduced in the ultrasonic image.

When performing spatial compounding in the illustrated ultrasound diagnostic apparatus 10, as conceptually shown in FIG. 2, the probe 16 basically transmits and receives the same as in the case of obtaining a normal ultrasound image (hereinafter referred to as “transmission”). , Normal transmission / reception), transmission / reception in which the direction of transmission / reception is tilted by an angle θ (transmission / transmission with an angle θ deflection), and normal transmission / reception, the transmission / reception direction is inclined by −θ Three types of transmission / reception are performed.
That is, in the illustrated example, when performing spatial compounding, basically, these three types of transmission / reception are regarded as one frame (unit) for obtaining one synthesized ultrasonic image, and transmission / reception of this one frame is performed. Repeat.

  In addition, the diagnostic apparatus main body 14 (image composition unit 80 described later) basically obtains an ultrasonic image A (solid line) obtained by normal transmission / reception, and transmission / reception with an angle inclined by θ with respect to normal transmission / reception. Three ultrasonic images of the obtained ultrasonic image B (broken line) and ultrasonic image C (dashed line) obtained by transmission / reception with the angle tilted by −θ are synthesized, and an ultrasonic image A region is A synthetic ultrasound image is generated.

  Accordingly, in the illustrated example, the predetermined number of ultrasonic images to be synthesized by the spatial compound is 3. In other words, in the illustrated example, the number of ultrasonic images to be combined with the spatial compound in the steady state (that is, the maximum number of ultrasonic images to be combined) is 3.

In the present invention, the predetermined number of ultrasonic images to be synthesized by spatial compound is not limited to 3, and may be 2 or 4 or more.
In addition, such a method of transmitting and receiving in different directions (ultrasonic waves) is not limited to a method based on a delay of ultrasonic transmission and reception as conceptually shown in FIG. Various known methods, such as those described, can be used.
Furthermore, in the illustrated example, the linear type is described as an example. However, as described above, the present invention can be used for various types of probes such as a convex type and a sector type.

Here, as described above, the probe 16 is provided with the temperature measuring means 42 for measuring the temperature of the signal processing unit 20, and the temperature measurement result is supplied to the transmission control unit 32 and the reception control unit 34. Is done.
Further, the probe 16 (the transmission control unit 32 and the reception control unit 34) has a temperature threshold value of T1 [° C.] as a first temperature and T2 [° C.] as a second temperature higher than this T1. ] Is set. In the ultrasonic diagnostic apparatus 10 of the present invention, T1 and T2 may be fixed or variable as long as the relationship of T1 <T2 is maintained.

When performing spatial compounding, if the temperature measurement result by the temperature measurement means 42 is less than T1, that is, if the temperature of the probe 16 (signal processing unit 20) is in a steady state, All three types of transmission / reception (corresponding to three ultrasonic images) are performed.
As an example, the transmission control unit 32 and the reception control unit 34 first control the drive of the transmission drive unit 30 and each individual signal processing unit 20a so as to perform normal transmission / reception for obtaining the ultrasound image A. Hereinafter, for convenience, this normal transmission / reception is referred to as “transmission / reception of image A”.
Next, the transmission control unit 32 and the reception control unit 34 perform transmission / reception in the direction in which the angle is inclined by θ with respect to normal transmission / reception for obtaining the ultrasound image B, and each individual signal. Controls the driving of the processing unit 20a. Hereinafter, for the sake of convenience, transmission / reception with this angle inclined by θ is referred to as “transmission / reception of image B”.
Further, the transmission control unit 32 and the reception control unit 34 perform transmission / reception in the direction in which the angle is inclined by −θ with respect to normal transmission / reception for obtaining the ultrasonic image C, and each of the transmission driving unit 30 and each individual transmission / reception unit 30. Controls driving of the signal processing unit 20a. Hereinafter, for convenience, transmission / reception with this angle inclined by −θ is referred to as “transmission / reception of image C”.

  That is, when the temperature measurement result by the temperature measurement means 42 is less than T1, as shown conceptually in FIG. 3A, transmission / reception of image A, transmission / reception of image B, and image C are performed in one frame. All three types of transmission and reception are performed. That is, transmission and reception for three images are performed. In the diagnostic apparatus main body 14, one synthesized ultrasonic image is generated from the three ultrasonic images obtained in one frame.

On the other hand, when the temperature measurement result by the temperature measurement unit 42 is T1 or more and less than T2, the probe reduces transmission / reception for generating a synthetic ultrasound image by one image in one frame, thereby obtaining two images. Minute transmission / reception is performed, and transmission / reception is not performed for one image (a pause period is provided). That is, when the temperature is equal to or higher than T1 and lower than T2, one type is reduced from three types of transmission / reception, and two types of transmission / reception are performed.
As an example, when the temperature measurement result is T1 or more and less than T2, the probe 12 first transmits / receives the image A in one frame, then transmits / receives the image B, and transmits / receives the next image C. Does not.
That is, when the temperature measurement result by the temperature measurement means 42 is T1 or more and less than T2, as conceptually shown in FIG. 3B, one frame is transmitted / received, the image B is transmitted / received, and “rest” is performed. This frame is repeated. In the diagnostic apparatus main body 14, one synthesized ultrasonic image is generated from two ultrasonic images obtained in one frame.

Furthermore, when the temperature measurement result by the temperature measuring means 42 is T2 or more, the probe reduces transmission / reception for generating a synthetic ultrasonic image by two images in one frame, and transmits / receives only one image. Do not send or receive two images (make the pause time longer). That is, when the temperature is equal to or higher than T2, two types are reduced from the three types of transmission / reception, and only one type is transmitted / received.
As an example, when the temperature measurement result is T2 or more, the probe 12 first transmits / receives the image A in one frame, then does not transmit / receive the image B, and further the next image C Does not send or receive.
That is, when the temperature measurement result by the temperature measuring means 42 is T1 or more and less than T2, as shown conceptually in FIG. 3B, one frame is transmitted / received, “pause”, and “pause”. This frame is repeated. In the diagnostic apparatus main body 14, one synthesized ultrasound image is generated from one ultrasound image obtained in one frame. In other words, the ultrasonic diagnostic apparatus 10 does not perform spatial compounding when the temperature measurement result by the temperature measurement means 42 is T2 or more.

As is clear from the above description, in the ultrasonic diagnostic apparatus 10 of the present invention, when the temperature of the probe 12 rises when performing spatial compounding, a frame for generating a synthesized ultrasonic image by the spatial compound. The drive time of the signal processing unit 20 or the like is reduced without changing the rate. That is, when the temperature of the probe 12 rises, the driving of the heat generating unit such as the signal processing unit 20 is stopped according to the temperature.
Therefore, in the present invention, even when the temperature of the probe 12 rises during spatial compounding, the temperature inside the probe 12 is quickly lowered by suspending the heat generating part such as the signal processing part 20. be able to. Moreover, even if the temperature rise of the probe 12 occurs by suppressing the temperature rise in the probe 12 and quickly reducing it, image quality deterioration can be minimized.

In the example shown in FIG. 3, the order of transmission / reception of each image in one frame is the same in all frames. However, the present invention is not limited to this, and the order of transmission / reception of each image in each frame. May be different. Further, the order of transmission / reception of each image in each frame may be different depending on whether the temperature measurement result by the temperature measurement means 42 is T1 or more and less than T2 and T2 or more.
An example is shown in FIGS. In the following description, in order to simplify the description, “transmission / reception” in “transmission / reception of image x” is omitted, and is also referred to as “image x”.

For example, if the temperature measurement result by the temperature measuring means 42 is less than T1, the first frame is “image A → image B → image C” and the second frame is “image” as shown in FIG. C → Image B → Image A ”, and the third frame may be“ Image A → Image B → Image C ”...
When the temperature measurement result by the temperature measuring means 42 is T1 or more and less than T2 and the image C is paused, as shown in FIG. 4B, the first frame is “image A → image B → pause”. The second frame may be “image B → image A → pause”, and the third frame may be “image A → image B → pause”.

That is, in the present invention, the transmission / reception directions of the closest ultrasonic images may be the same in consecutive frames (that is, synthesized ultrasonic images that are temporally continuous).
According to such a transmission / reception order, transmission / reception in the same direction is continued, so that control of the transmission drive unit 30 and the individual signal processing unit 20a can be simplified.

  Further, at this time, when the temperature measurement result by the temperature measuring means 42 is T1 or more and less than T2 and the image C is paused, as shown in FIG. B → rest ”, second frame“ rest → image B → image A ”, third frame“ image A → image B → rest ”, etc .. May be.

In the above example, the number of pauses according to the temperature measurement result is the same in all frames, but the present invention is not limited to this, and the number of pauses in each frame is different. Also good. That is, in the present invention, when the temperature in the probe 12 rises, the transmission / reception may be suspended within two frames before and after.
For example, when the temperature measurement result by the temperature measurement means 42 is T1 or more and less than T2, as shown in FIG. 5A, the first frame is “image B → image A → image C”, and the second frame is “Image C → Image A → Pause”, the third frame may be “Image A → Image B → Pause”, and the fourth frame may be “Image B → Image A → Image C”.
When the temperature measurement result by the temperature measuring means 42 is T2 or more, as shown in FIG. 5B, the first frame is “image B → image A → pause”, and the second frame is “pause → The third frame may be “pause → image A → pause”, the fourth frame may be “image A → image B → pause”, and so on.

  In the example shown in FIG. 5, as in the example shown in FIG. 4, the transmitting and receiving directions of the closest ultrasonic images in the continuous frames are the same. However, in the aspect in which the number of synthesized ultrasonic images is different in consecutive frames shown in FIG. 5, the present invention is not limited to this, and the transmission / reception direction of the closest ultrasonic image is different as in the example shown in FIG. 3. Good.

In the above example, it is the transmission / reception of the image B and / or the transmission / reception of the image C that pauses when the temperature in the probe 12 rises, but the present invention is not limited to this. That is, according to the temperature rise, transmission / reception of the image A may be paused, and a composite ultrasonic image of the region of the ultrasonic image A may be generated from transmission / reception of the image B and transmission / reception of the image C.
However, the synthesized ultrasonic image generated by the diagnostic apparatus main body 14 is an image of the region of the ultrasonic image A. Therefore, it is also possible to stably obtain an appropriate composite ultrasonic image by performing transmission / reception of the image A (that is, transmission / reception including the entire region of the composite ultrasonic image). In addition, when transmission / reception becomes one image according to temperature rise, in order to output the ultrasonic image of a predetermined area | region, it is necessary to perform transmission / reception of the image A which is normal transmission / reception.

Further, in the above example, since the predetermined number when performing spatial compounding is 3, the threshold value of the temperature is set to two points. However, the present invention is not limited to this, and the predetermined number is 4 or more. May provide three or more threshold values.
Further, even when the predetermined number is 4 or more, or even when the threshold is 3 points or more, a mode in which the order of transmission / reception of each image is different in the continuous frames shown in FIG. 4 or transmission / reception performed in the continuous frames shown in FIG. Of course, embodiments with different numbers of can be used.

As described above, the reception signal output from the probe 12 is supplied to the diagnostic apparatus body 14 by wireless communication.
The diagnostic apparatus main body 14 includes a wireless communication unit 52 to which an antenna 50 is connected. A data storage unit 56 is connected to the wireless communication unit 52 via a serial / parallel conversion unit 54, and an image is generated in the data storage unit 56. The part 58 is connected. Further, a display unit 64 is connected to the image generation unit 58 via the display control unit 62.
A communication control unit 68 is connected to the wireless communication unit 52, and a main body control unit 70 is connected to the serial / parallel conversion unit 54, the image generation unit 58, the display control unit 62, and the communication control unit 68. The main body control unit 70 controls each unit in the diagnostic apparatus main body 14, and is connected to an operation unit 72 for performing various input operations such as whether or not to perform spatial compounding.

The diagnostic device main body 14 includes a power supply unit (not shown), and power for driving is supplied to each part from the power supply unit.
Further, the diagnostic device main body 14 may have a charging means for charging a battery built in the probe 12.

The wireless communication unit 52 transmits various control signals to the probe 12 by performing wireless communication with the probe 12. In addition, the wireless communication unit 52 demodulates a signal received by the antenna 50 to output serial sample data.
The communication control unit 68 controls the wireless communication unit 52 so that various control signals are transmitted with the transmission radio wave intensity set by the main body control unit 70.
The serial / parallel converter 54 converts the serial sample data output from the wireless communication unit 52 into parallel sample data. The data storage unit 56 includes a memory or a hard disk, and stores at least one frame of sample data converted by the serial / parallel conversion unit 54.

  The image generation unit 58 performs reception focus processing or the like on the sample data for each image read from the data storage unit 56 and generates an image signal representing an ultrasonic image. The image generation unit includes a phasing addition unit 76, an image processing unit 78, and an image synthesis unit 80.

  The phasing addition unit 76 selects one reception delay pattern from a plurality of reception delay patterns stored in advance according to the reception direction set in the main body control unit 21, and sets the selected reception delay pattern. Based on this, the reception focus process is performed by adding a delay to each of the plurality of complex baseband signals represented by the sample data. By this reception focus processing, a baseband signal (sound ray signal) in which the focus of the ultrasonic echo is narrowed is generated.

The image processing unit 78 generates an image signal of an ultrasonic image (B mode image) that is tomographic image information related to the tissue in the subject based on the sound ray signal generated by the phasing addition unit 76.
The image processing unit 78 includes an STC (sensitivity time control) unit and a DSC (digital scan converter). The STC unit corrects the attenuation due to the distance according to the depth of the reflection position of the ultrasonic wave on the sound ray signal. The DSC converts the sound ray signal corrected by the STC unit into an image signal conforming to a normal television signal scanning method (raster conversion), and performs necessary image processing such as gradation processing to thereby obtain an ultrasonic image signal. Is generated.

The image synthesizing unit 80 synthesizes an ultrasonic image when performing spatial compounding.
The ultrasonic diagnostic apparatus 10 basically synthesizes three ultrasonic images when performing spatial compounding. Here, in the ultrasonic diagnostic apparatus 10, the temperature of the reception processing unit 20 is measured by the temperature measuring means 42, and this ultrasonic image is synthesized by a spatial compound every time the temperature rises by one step from the set temperature threshold value. Is appropriately reduced to increase the pause time of the reception processing unit 20 and the like.
As an example, when performing spatial compounding, the probe 12 transmits and receives an image A as shown in FIG. 3A if the temperature is lower than T1 according to the temperature measurement result by the temperature measuring means 42. Image B and image C are transmitted and received. Further, when the temperature measured by the temperature measuring means 42 is equal to or higher than T1 and lower than T2, the probe 12 performs only the transmission / reception of the image A and the transmission / reception of the image B as shown in FIG. 3B (transmission / reception of the image C). Is paused). Further, when the temperature measured by the temperature measuring means 42 is equal to or higher than T2, the probe 12 performs only transmission / reception of the image A (transmission / reception of the image B and the image C is suspended) as shown in FIG.

In response to this, when performing spatial compounding, the image synthesizing unit 80 synthesizes three images of ultrasonic images that are transmitted and received according to the temperature of the reception processing unit 20 measured by the temperature measuring means 42. Alternatively, two ultrasonic images are synthesized or one ultrasonic image is synthesized (no image synthesis).
In the example shown in FIG. 3 described above, when the temperature measured by the temperature measuring unit 42 is less than T1, the image composition unit 80 transmits the ultrasonic image A by transmitting / receiving the image A and the ultrasonic image B by transmitting / receiving the image B. , And synthesis of the ultrasonic image C by transmission / reception of the image C, and an image signal of the synthesized ultrasonic image is generated.
When the temperature measured by the temperature measuring means 42 is T1 or more and less than T2, the image synthesis unit 80 synthesizes the ultrasonic image A by transmission / reception of the image A and the ultrasonic image B by transmission / reception of the image B, An image signal of the synthesized ultrasonic image is generated.
Furthermore, when the temperature measured by the temperature measuring means 42 is equal to or higher than T2, only the ultrasonic image A obtained by transmitting and receiving the image A is supplied, so the image composition unit 80 does not perform image composition and does not perform the image composition. The image signal is output as it is (similar to the generation of a normal ultrasonic image).

The display control unit 62 causes the display unit 64 to display an ultrasonic image based on the image signal generated by the image generation unit 58.
The display unit 64 includes a display device such as an LCD, for example, and displays an ultrasonic image under the control of the display control unit 62.

Hereinafter, the operation of the ultrasonic diagnostic apparatus 10 shown in FIG. 1 will be described.
In the ultrasonic diagnostic apparatus 10, at the time of diagnosis, first, ultrasonic waves are transmitted from the plurality of transducers 18 in accordance with the drive voltage supplied from the transmission drive unit 30 of the probe 12.
The ultrasonic waves are reflected by the subject, and the reception signals output from the transducers 18 that have received the ultrasonic echoes from the subject are supplied to the corresponding individual signal processing units 20a to generate sample data.

Here, in the probe 12, when performing spatial compounding, the temperature measurement result of the signal processing unit 20 by the temperature measuring unit 42 is sent to the transmission control unit 32 and the reception control unit 34.
In the ultrasonic diagnostic apparatus 10, each time the temperature of the reception processing unit 20 increases the set temperature threshold by one step, the number of ultrasonic images to be synthesized by the spatial compound is appropriately determined according to the temperature measurement result. cut back. Therefore, in the probe 12, the number of ultrasonic images to be transmitted / received is appropriately reduced according to the temperature measurement result of the signal processing unit 20 by the temperature measuring unit 42, and the rest time of the reception processing unit 20 and the like is increased.
As an example, when the temperature is lower than T1, the transmission control unit 32 and the reception control unit 34 transmit and receive an image A, as shown in FIG. The operations of the transmission drive unit 30 and the signal processing unit 20 (each signal processing unit 20a) are controlled so as to perform transmission / reception of the image B and transmission / reception of the image C.
Further, the transmission control unit 32 and the reception control unit 34 transmit and receive the image A and transmit and receive the image B as shown in FIG. 3B when the measured temperature result by the temperature measuring unit 42 is T1 or more and less than T2. And the operations of the transmission drive unit 30 and the signal processing unit 20 are controlled so that transmission / reception of the image C is suspended.
Further, when the temperature measured by the temperature measuring unit 42 is equal to or higher than T2, the transmission control unit 32 and the reception control unit 34 perform only transmission / reception of the image A as illustrated in FIG. The operations of the transmission drive unit 30 and the signal processing unit 20 are controlled so that transmission / reception of C is suspended.

  The sample data generated by the individual signal processing unit 20a is sent to the parallel / serial conversion unit 24, serialized, and then wirelessly transmitted from the wireless communication unit 26 (antenna 28) to the diagnostic apparatus body 14.

The sample data received by the wireless communication unit 52 of the diagnostic apparatus main body 14 is converted into parallel data by the serial / parallel conversion unit 54 and stored in the data storage unit 56.
Further, sample data for each image is read from the data storage unit 56, an image signal of an ultrasonic image is generated by the image generation unit 58, and the ultrasonic image is displayed by the display control unit 62 based on this image signal. 64.

When performing spatial compounding, the image synthesis unit 80 of the image generation unit 58 synthesizes an ultrasonic image.
Here, as described above, in the ultrasonic diagnostic apparatus 10, the number of ultrasonic images to be synthesized by the spatial compound is appropriately reduced every time the temperature of the reception processing unit 20 increases the set temperature threshold by one step. . In response to this, the image composition unit 80 performs composition of three images, composition of two images, or composition of one image according to the temperature of the reception processing unit 20 (no image composition).
That is, in the example shown in FIG. 3 described above, when the temperature measured by the temperature measuring unit 42 of the probe 12 is less than T1, the image composition unit 80 generates the ultrasonic images A and B by transmitting and receiving the image A. The ultrasonic image B by transmission / reception and the ultrasonic image C by transmission / reception of the image C are combined to generate an image signal of the combined ultrasonic image and output it to the display control unit 62.
When the temperature measured by the temperature measuring unit 42 of the probe 12 is T1 or more and less than T2, the image synthesis unit 80 synthesizes the ultrasonic image A by transmission / reception of the image A and the ultrasonic image B by transmission / reception of the image B. To generate an image signal of the synthesized ultrasonic image and output it to the display control unit 62.
Further, when the temperature measured by the temperature measuring means 42 of the probe 12 is equal to or higher than T2, the image synthesis unit 80 outputs the image signal of the ultrasonic image A to the display control unit 62 without performing image synthesis.

  Although the ultrasonic diagnostic apparatus of the present invention has been described in detail above, the present invention is not limited to the above-described example, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

  It can be suitably used for an ultrasonic diagnostic apparatus used for various diagnoses in a medical field.

DESCRIPTION OF SYMBOLS 10 Ultrasonic diagnostic apparatus 12 (ultrasonic wave) probe 14 Diagnostic apparatus main body 16 Piezoelectric element unit 18 Transducer 20 Signal processing part 20a Individual signal processing part 24 Parallel / serial conversion part 26, 52 Wireless communication part 28, 50 Antenna 30 Transmission drive part 32 transmission control unit 34 reception control unit 36 communication control unit 38 probe control unit 42 temperature measuring means 54 serial / parallel conversion unit 56 data storage unit 58 image generation unit 62 display control unit 64 display unit 68 communication control unit 70 main body control unit 72 Operation unit 76 Phase adjusting and adding unit 78 Image processing unit 80 Image composition unit

Claims (10)

Piezoelectric element unit that transmits ultrasonic waves, receives ultrasonic echoes reflected by the subject, and outputs a received signal corresponding to the received ultrasonic waves, and transmission control means for controlling transmission of ultrasonic waves by the piezoelectric element units An ultrasonic probe having signal processing means for processing the received signal output from the piezoelectric element unit, and temperature measuring means for measuring the temperature at a predetermined position;
A diagnostic apparatus main body that generates an ultrasonic image according to the received signal processed by the signal processing means of the ultrasonic probe;
The diagnostic apparatus body has a function of generating a single synthesized ultrasound image by synthesizing a predetermined number of the ultrasound images, and the ultrasound probe is configured so that the diagnostic apparatus body has a combined ultrasound image. In order to perform generation, it has a function of transmitting and receiving a plurality of types of ultrasonic waves of the same number as the predetermined number different from each other in the transmission and reception directions of ultrasonic waves,
The ultrasonic probe transmits / receives an ultrasonic wave for generating a synthetic ultrasonic image according to a temperature measurement result by the temperature measuring unit when the diagnostic apparatus main body generates a synthetic ultrasonic image. Is one or more types obtained by subtracting zero or more types from the plurality of types.   The ultrasonic diagnostic apparatus according to claim 1, wherein the temperature measuring unit measures a temperature of the signal processing unit.   When the diagnostic apparatus main body generates a synthetic ultrasonic image, the ultrasonic probe obtains an ultrasonic image including at least one type of transmission / reception of the ultrasonic waves that covers the entire area to be output as the synthetic ultrasonic image. The ultrasonic diagnostic apparatus according to claim 1, which transmits and receives transmitted ultrasonic waves. As the threshold value, a temperature T1 and a temperature T2 higher than the temperature T1 are set.
When the diagnostic apparatus main body generates a synthetic ultrasound image, the ultrasound probe determines that the plurality of the plurality of the ultrasonic probes when the temperature measurement result is less than the temperature T1 according to the temperature measurement result by the temperature measurement unit. When the temperature measurement result is equal to or higher than the temperature T2, the type of ultrasonic waves is transmitted and received, and the temperature measurement result is equal to or higher than the temperature T1 and lower than the temperature T2. In the case, the ultrasonic diagnostic apparatus according to any one of claims 1 to 3, wherein transmission / reception of a number of types of ultrasonic waves between the plurality of types and the minimum number is performed. As the threshold value, a temperature T1 and a temperature T2 higher than the temperature T1 are set.
When the diagnostic apparatus main body generates a synthetic ultrasound image, the ultrasound probe determines that the plurality of the plurality of the ultrasonic probes when the temperature measurement result is less than the temperature T1 according to the temperature measurement result by the temperature measurement unit. In the case where two types of ultrasonic waves are transmitted and received and the temperature measurement result is equal to or higher than the temperature T1, at least one of the two types of synthesized ultrasonic images that are temporally continuous subtracts one or more types from the plurality of types, and The ultrasonic diagnostic apparatus according to claim 1, wherein a plurality of types of ultrasonic waves having different subtractions from the plurality of types are transmitted and received.   When the temperature measurement result is equal to or higher than the temperature T1 and lower than the temperature T2, in one of the two or less synthesized ultrasonic images that are temporally continuous, ultrasonic transmission / reception obtained by subtracting one or more types from the plurality of types is performed. The ultrasonic diagnostic apparatus according to claim 5 to be performed.   When the temperature measurement result is equal to or higher than the T2, the ultrasonic transmission / reception is performed by subtracting one or more types from the plurality of types in both images of the two or less ultrasonic composite images that are temporally continuous. 6. The ultrasonic diagnostic apparatus according to 6.   The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic probe equalizes the ultrasonic transmission / reception direction of the closest ultrasonic image in the synthetic ultrasonic image that is temporally continuous.   When the diagnostic apparatus main body generates a synthetic ultrasonic image, the ultrasonic probe reduces the transmission and reception of two or more types of ultrasonic waves from the plurality of types. The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic waves are transmitted and received so that continuous ultrasonic images are reduced.   When the diagnostic apparatus main body generates a synthetic ultrasonic image, the ultrasonic probe reduces the transmission / reception of one or more types of ultrasonic waves from the plurality of types, and the synthesized ultrasonic image is temporally continuous. The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic waves are transmitted and received so as to reduce adjacent ultrasonic images.

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