JP2010233610A - Ultrasonic probe and ultrasonograph - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic probe and an ultrasonograph, wherein a plurality of ultrasonic transducers are allowed to move mutually independently and adhesion to a diagnosed part is further improved by improving following capability to the diagnosed part having a rugged shape. <P>SOLUTION: The ultrasonic probe which transmits ultrasound to the diagnosed part while an opposite surface is made opposite to the diagnosed part of a subject and receives an ultrasonic echo from the diagnosed part. The ultrasonic probe has a plurality of ultrasonic transducers which are arranged adjacently to each other in a column shape on the opposite surface in order to be brought into contact with the diagnosed part. The plurality of ultrasonic transducers are retractable respectively independently of the opposite surface on the basis of the contact with the diagnosed part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultrasound probe and an ultrasound diagnostic apparatus, and more particularly to an ultrasound probe and the like that enable mutual diagnosis of a plurality of ultrasound transducers and enable accurate diagnosis at an uneven diagnostic site.

  In the medical field, various imaging techniques have been developed in order to perform diagnosis by observing the inside of a subject. In particular, ultrasonic imaging that acquires internal information of a subject by transmitting and receiving ultrasonic waves can perform image observation in real time, and can also be used for other medical applications such as X-ray photographs and RI (radio isotopic) scintillation cameras. Unlike imaging technology, there is no radiation exposure. Therefore, ultrasonic imaging is used as a highly safe imaging technique in a wide range of fields including gynecological, circulatory, and digestive systems as well as fetal diagnosis in the obstetrics field.

  The principle of ultrasonic imaging is as follows. Ultrasound is reflected at the boundary between regions having different acoustic impedances, such as the boundary between structures in the subject. Therefore, an ultrasonic beam is transmitted into a subject such as a human body, an ultrasonic echo generated in the subject is received, and a reflection position and a reflection intensity at which the ultrasonic echo is generated are obtained. The contour of an existing structure (for example, a viscera or a diseased tissue) can be extracted.

  In the ultrasonic diagnostic apparatus, an ultrasonic probe is directly brought into contact with a subject (patient) to emit ultrasonic waves to the patient and receive the ultrasonic echoes. The ultrasonic probe has an ultrasonic transducer for transmitting and receiving ultrasonic waves inside, and ultrasonic waves are transmitted and received by bringing the ultrasonic transducer into contact with a subject.

  In order to acquire a high-quality ultrasonic echo image and perform a more appropriate diagnosis, it is necessary to make the contact state between the ultrasonic transducer and the subject sufficiently close and to eliminate the air layer between them. However, the patient's diagnosis site is often curved or uneven, and the ultrasonic transducer and the diagnosis site may not be sufficiently adhered. Therefore, jelly is often applied to the diagnostic surface (contact surface) of the ultrasonic probe in order to eliminate the air layer between the ultrasonic transducer and the diagnostic region as much as possible.

  Further, in order to appropriately perform an ultrasonic diagnosis at a diagnostic region having a larger curvature, for example, a configuration as disclosed in Patent Document 1 or Patent Document 2 has been proposed. Patent Document 1 discloses an angle sensor in which a plurality of ultrasonic probes are connected by a link mechanism to facilitate application to a diagnostic part having a large curvature, and the angular posture of the ultrasonic probes is arranged between the ultrasonic probes. The configuration detected by is disclosed. Further, in Patent Document 2, a plurality of transducers (transducers) are installed in a flexible substrate to facilitate application to a diagnostic part having a large curvature. A configuration for detecting deflection is disclosed.

Japanese Patent Laid-Open No. 2005-137581 JP-A-10-42395

  However, in the configurations disclosed in Patent Documents 1 and 2, since the ultrasonic probes or the vibrators (hereinafter referred to as vibrators) are connected, for example, the following is listed. May cause serious problems.

  First, since the vibrators and the like are connected to each other, there is a problem that the movement of one vibrator and the like affects other vibrators and the like. For example, when a certain part is not sufficiently in close contact with the diagnostic part, if a vibrator or the like that is in contact with that part is strongly pressed against the diagnostic part, the other vibrators are also dragged and moved. End up.

  Secondly, since the sensor is disposed between the vibrators and the like, there is a problem that an unmeasurable region occurs between the vibrators and the like corresponding to the sensor placement position. Since an ultrasonic echo of a portion corresponding to the angle sensor or the deflection detection sensor cannot be obtained, a portion where an echo image cannot be formed partially occurs.

  Thirdly, there is a problem that it is difficult to achieve sufficient adhesion to a diagnostic region that is locally a large convex portion or concave portion. Even if the vibrators and the like are connected by a link mechanism or a flexible substrate, there is a limit to the shape following ability to the local uneven shape, for example, in a part where there is a nipple, umbilicus, mole, etc. It is difficult to maintain sufficient contact with the diagnostic site.

  Fourth, there is a problem that it is difficult to apply to concave diagnostic sites. That is, the vibrator has a thickness in the depth direction, and when the vibrator is applied to the concave diagnostic site, the vibrators adjacent in the depth direction interfere with each other. Therefore, there is a limit to the conformability of the shape to the concave diagnostic site.

  Fifth, when these configurations are applied to a diagnostic part having a concavo-convex shape, there is a problem that the relative angle between the vibrators and the like changes. For this reason, the intensity of the ultrasonic wave transmitted from each vibrator or the like varies.

  The present invention has been made in view of the above circumstances, and enables independent movement of a plurality of ultrasonic transducers, and improves adherence to a diagnostic site having irregularities, thereby improving adhesion to the diagnostic site. It is an exemplary problem to provide a further improved ultrasonic probe and ultrasonic diagnostic apparatus.

  In order to solve the above-described problem, an ultrasonic probe as an exemplary aspect of the present invention transmits an ultrasonic wave to a diagnostic site with a facing surface facing a diagnostic site of a subject, and transmits from the diagnostic site. An ultrasonic probe for ultrasonic diagnosis that receives an ultrasonic echo, and has a plurality of ultrasonic transducers arranged adjacent to each other in a row on an opposing surface in order to make contact with a diagnostic site, and a plurality of ultrasonic waves Each of the transducers can advance and retreat independently with respect to the opposing surface based on contact with the diagnostic site.

  The plurality of transducers may be capable of moving back and forth along a direction orthogonal to the facing surface, or may be two-dimensionally arranged in a row on the facing surface. Moreover, you may have further the urging means which urges | biases a some ultrasonic transducer in the direction which advances from an opposing surface. A detecting means for detecting the advance / retreat amounts of the plurality of ultrasonic transducers may be further provided, and the cross-sectional shape in the direction orthogonal to the advance / retreat direction of the ultrasonic transducers may be a polygonal shape.

  An ultrasonic diagnostic apparatus according to another exemplary aspect of the present invention includes an ultrasonic probe having the above-described detection means, and a delay based on an advance / retreat amount of each ultrasonic transducer with respect to an ultrasonic echo received by the ultrasonic probe. A delay processing unit that executes processing, an image processing unit that generates an echo image from the ultrasonic echo after the delay processing, and a display unit that displays the echo image are provided. The ultrasonic diagnostic apparatus may further include a profile display unit that displays the profile of the diagnostic region on the display unit based on the advance / retreat amount of each ultrasonic transducer.

  Further objects and other features of the present invention will become apparent from the preferred embodiments described below with reference to the accompanying drawings.

  According to the present invention, adjacent ultrasonic transducers can advance and retract independently from each other, so that high shape following capability can be achieved even for a diagnostic site having a local uneven shape or a concave shape having a large curvature. The ultrasonic probe can be satisfactorily adhered to the diagnostic site. Since the adjacent ultrasonic transducers are not connected to each other, the advancing and retreating movements do not affect each other. If the ultrasonic transducers are arranged two-dimensionally, it is possible to provide a three-dimensional echo image as an auto-scan type ultrasonic diagnostic apparatus.

  Since the sensors are not arranged between the ultrasonic transducers arranged in a row but are arranged adjacent to each other, it is possible to reduce the occurrence of a non-measurable region and the occurrence of ultrasonic strength variation. Further, if the advance / retreat amount of the ultrasonic transducer is detected by the detection means, a delay process based on the advance / retreat amount can be performed, and a higher-quality ultrasonic echo image can be generated.

1 is a configuration diagram showing an outline of the overall configuration of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. It is a block block diagram which shows the outline of the internal structure of the ultrasonic diagnosing device shown in FIG. It is a figure which shows the 1st structural example of the transmission / reception part shown in FIG. It is a wave form diagram which shows the sampling by ADC shown in FIG. It is a wave form diagram which shows sampling by the sampling part shown in FIG. It is a figure which shows the 2nd structural example of the transmission / reception part shown in FIG. It is a figure which shows the 3rd structural example of the transmission / reception part shown in FIG. It is a wave form diagram for demonstrating operation | movement of the orthogonal sampling part shown in FIG. It is a block block diagram which shows the outline of the internal structure of the ultrasonic probe which concerns on the modification 1 in embodiment of this invention. It is a block block diagram which shows the outline of the internal structure of the ultrasonic probe which concerns on the modification 2 in embodiment of this invention. It is a side sectional view showing the outline of the internal configuration in the vicinity of the ultrasonic transducer of the ultrasonic probe according to the first embodiment of the present invention. FIG. 10B is a state diagram showing a state in which the ultrasonic probe in FIG. It is an enlarged view which expands and shows the holding structure of the ultrasonic transducer by the holding plate shown to FIG. 10A. It is a figure which shows the case where the cross-sectional shape of the ultrasonic transducer shown to FIG. 10A is a circular cross-sectional shape from the opposing surface side. It is a figure which shows the case where the cross-sectional shape of the ultrasonic transducer shown to FIG. 10A is a triangular cross-sectional shape from the opposing surface side. It is a figure which shows the case where the cross-sectional shape of the ultrasonic transducer shown to FIG. 10A is a hexagonal cross-sectional shape from the opposing surface side. It is an external view of the ultrasonic probe which concerns on Embodiment 2 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same referential mark is attached | subjected to the same component and description is abbreviate | omitted.

  FIG. 1 is a configuration diagram showing an outline of the overall configuration of an ultrasonic diagnostic apparatus S according to an embodiment of the present invention, and FIG. 2 is a block configuration diagram showing an outline of an internal configuration of the ultrasonic diagnostic apparatus S. As shown in FIGS. 1 and 2, this ultrasonic diagnostic apparatus S is roughly configured to include an ultrasonic probe (ultrasonic probe) 1 according to an embodiment of the present invention and an apparatus main body 2. .

  The electrical configuration of the ultrasonic probe 1 and the apparatus main body 2 and mutual signal transmission / reception will be described first, and then the configuration in the vicinity of the ultrasonic transducer 10 in the ultrasonic probe 1 will be described.

  The ultrasonic probe 1 may be an external probe such as a linear scan method, a convex scan method, or a sector scan method, or an ultrasonic endoscope probe such as a radial scan method. As shown in FIG. 2, the ultrasonic probe 1 includes a plurality of ultrasonic transducers 10 constituting a one-dimensional or two-dimensional transducer array, a plurality of channels of transmission / reception units 20, a serialization unit 30, probe-side control, and A delay processing unit 40 and a transmission circuit 50 are included.

  The plurality of ultrasonic transducers 10 transmit ultrasonic waves according to a plurality of applied driving signals, receive propagating ultrasonic echoes, and output a plurality of reception signals. Each ultrasonic transducer is, for example, a piezoelectric ceramic represented by PZT (lead zirconate titanate: Pb (lead) zirconate titanate) or a polymer piezoelectric element represented by PVDF (polyvinylidene fluoride). It is constituted by a vibrator in which electrodes are formed at both ends of a piezoelectric material (piezoelectric body).

  When a pulsed or continuous wave voltage is applied to the electrodes of such a vibrator, the piezoelectric body expands and contracts. By this expansion and contraction, pulsed or continuous wave ultrasonic waves are generated from the respective vibrators, and an ultrasonic beam is formed by synthesizing these ultrasonic waves. Each vibrator expands and contracts by receiving propagating ultrasonic waves and generates an electrical signal. These electrical signals are output as ultrasonic reception signals.

  The multi-channel transmission / reception unit 20 generates a plurality of drive signals under the control of the probe side control and the delay processing unit 40, supplies the drive signals to the plurality of ultrasonic transducers 10, and also generates a plurality of ultrasonic waves. Sample data obtained by subjecting a plurality of received signals output from the transducer 10 to quadrature detection processing or the like is supplied to the serialization unit 30.

  FIG. 3 is a diagram illustrating a first configuration example of the transmission / reception unit illustrated in FIG. 2. As shown in FIG. 3, the transmission / reception unit 20 of each channel includes a transmission circuit 21, a preamplifier 22, a low-pass filter (LPF) 23, an analog / digital converter (ADC) 24, an orthogonal detection processing unit 25, Sampling units 26a and 26b and memories 27a and 27b are included. Here, the transmission circuit 21 to the quadrature detection processing unit 25 constitute signal processing means.

  The transmission circuit 21 is configured by, for example, a pulser, generates a drive signal under the control of the probe side control and delay processing unit 40, and supplies the generated drive signal to the ultrasonic transducer 10. The probe-side control and delay processing unit 40 shown in FIG. 2 controls the operation of the transmission circuit 21 of a plurality of channels based on the scanning control signal output from the transmission circuit 50. For example, the probe-side control and delay processing unit 40 selects one pattern from a plurality of delay patterns according to the transmission direction set by the scanning control signal, and a plurality of ultrasonic transducers based on the pattern. The delay time given to each of the ten drive signals is set. Alternatively, the probe-side control and delay processing unit 40 may set the delay time so that the ultrasonic waves transmitted from the plurality of ultrasonic transducers 10 reach the entire imaging region of the subject.

  Based on the transmission delay pattern selected by the probe-side control and delay processing unit 40, the multi-channel transmission circuit 21 has a plurality of ultrasonic waves transmitted from the plurality of ultrasonic transducers 10 so as to form an ultrasonic beam. The delay amount of the drive signal is adjusted and supplied to the plurality of ultrasonic transducers 10, or the plurality of drive signals are transmitted so that the ultrasonic waves transmitted from the plurality of ultrasonic transducers 10 reach the entire imaging region of the subject. Is supplied to a plurality of ultrasonic transducers 10.

  The preamplifier 22 amplifies the reception signal (RF signal) output from the ultrasonic transducer 10, and the LPF 23 limits the band of the reception signal output from the preamplifier 22, thereby preventing aliasing in A / D conversion. To do. The ADC 24 converts the analog reception signal output from the LPF 23 into a digital reception signal. For example, if the ultrasonic frequency is about 5 MHz, a sampling frequency of 40 MHz is used. In that case, if the sound speed in the living body is about 1530 m / sec, the in-vivo distance corresponding to one sample is about 0.038 mm. Therefore, in consideration of the round trip of ultrasonic waves, data up to a depth of about 15.7 cm can be obtained by acquiring 8192 samples.

If the number of ultrasonic transducers 10 in the reception aperture is 64, and 100 ultrasonic reception lines (sound rays) are required for one frame of the ultrasonic diagnostic image, the image of one frame is displayed. The necessary data amount is 8192 × 64 × 100≈52 × 10 ⁶ , and in order to display an image of 10 frames per second, data transfer of about 520 × 10 ⁶ / sec is required. Here, since the resolution required for the ultrasonic diagnostic image is usually about 12 bits for one piece of data, a transmission bit rate of about 6240 Mbps is required to transmit the above data.

  Thus, when data is serialized with an RF signal as it is, the transmission bit rate becomes extremely high, and the communication speed and the operation speed of the memory cannot keep up with it. On the other hand, if data is serialized after beam forming processing for combining RF signals from a plurality of ultrasonic transducers 10 and matching the phase of the beam, the transmission bit rate can be reduced. However, the circuit for reception focus processing is large in scale, and it is difficult to incorporate it into an ultrasonic probe. Therefore, in the present embodiment, the transmission bit rate is reduced by performing orthogonal detection processing or the like on the received signal to reduce the frequency band of the received signal to the baseband frequency band and then serializing the data. Yes.

The quadrature detection processing unit 25 performs quadrature detection processing on the received signal to generate a complex baseband signal (I signal and Q signal). As shown in FIG. 3, the quadrature detection processing unit 25 includes mixers (multiplication circuits) 25a and 25b and low-pass filters (LPF) 25c and 25d. The mixer 25a multiplies the received signal converted into a digital signal by the ADC 24 with the local oscillation signal cosω ₀ t, and the LPF 25c applies a low-pass filter process to the signal output from the mixer 25a, thereby representing the real component. A signal is generated. On the other hand, the mixer 25b multiplies the received signal converted into the digital signal by the ADC 24 with the local oscillation signal sin ω ₀ t rotated in phase by π / 2, and the LPF 25d applies the low-pass filter to the signal output from the mixer 25b. By performing the processing, a Q signal representing an imaginary component is generated.

  The sampling units 26 a and 26 b sample (resample) the complex baseband signals (I signal and Q signal) generated by the quadrature detection processing unit 25 to generate 2-channel sample data, respectively. The generated 2-channel sample data is stored in the memories 27a and 27b, respectively.

  Here, if the baseband signal is sampled at a frequency twice the baseband frequency band, the signal information is retained. Therefore, a sampling frequency of 5 MHz is sufficient. As a result, the sampling frequency is reduced from 40 MHz to 5 MHz as compared with the case of serializing data with an RF signal as it is, so the data amount becomes 1/8 and the number of samples up to a depth of about 15.7 cm is reduced. There will be 1024 pieces. However, in order to maintain signal information by envelope detection, it is necessary to maintain phase information. Therefore, it is necessary to generate complex baseband signals (I signal and Q signal) by quadrature detection processing, etc. The number of channels is doubled.

Therefore, the amount of data necessary to display an image of one frame is 1024 × 64 × 100 × 2≈about 13.1 × 10 ^{6. In} order to display an image of 10 frames per second, the resolution is 12 As a bit, a transmission bit rate of about 1572 Mbps is required. If the sampling frequency is 2.5 MHz, the number of samples up to a depth of about 15.7 cm is 512, and the amount of data can be further reduced by half, so that the transmission bit rate can be reduced to about 786 Mbps. it can.

  4A and 4B are waveform diagrams showing a comparison between sampling by the ADC shown in FIG. 3 and sampling by the sampling unit. FIG. 4A shows three channels Ch. 1-Ch. 3 shows sampling by the ADC 24, and FIG. 4B shows three channels Ch. 1-Ch. 3, sampling by the sampling unit 26a is shown. Compared with the case where the sample data is transmitted by sampling the RF signal as shown in FIG. 4A, the transmission bit rate is greatly increased by sampling the baseband signal and transmitting the sample data as shown in FIG. 4B. Can be reduced.

  FIG. 5 is a diagram illustrating a second configuration example of the transmission / reception unit illustrated in FIG. 2. In the second configuration example shown in FIG. 5, a time-division sampling unit 26c is provided in place of the sampling units 26a and 26b in the first configuration example shown in FIG. 3, and the memory 27c is used instead of the memories 27a and 27b. Is provided.

The time division sampling unit 26c generates two series of sample data by alternately sampling (resampling) the I signal and the Q signal generated by the quadrature detection processing unit 25 in a time division manner. For example, time-division sampling unit 26c performs sampling in synchronization with the I signal to the phase of the cos .omega ₀ t, sampled synchronously with the Q signal to the phase of sin .omega ₀ t. The generated two series of sample data is stored in the memory 27c. Thereby, a memory circuit can be made into one system.

  FIG. 6 is a diagram illustrating a third configuration example of the transmission / reception unit illustrated in FIG. 2. In the third configuration example shown in FIG. 6, an orthogonal sampling unit 25e is provided instead of the mixers 25a and 25b in the second configuration example shown in FIG.

FIG. 7 is a waveform diagram for explaining the operation of the orthogonal sampling unit shown in FIG. Quadrature sampling unit 25e is a received signal converted to a digital signal in synchronization with the phase of the cos .omega _{0 t} to generate a first signal sequence by sampling by ADC 24, synchronizes the received signal to the phase of sin .omega _{0 t} To generate a second signal sequence.

  Further, the LPF 25c performs low-pass filter processing on the first signal sequence output from the orthogonal sampling unit 25e, thereby generating an I signal representing a real component, and the LPF 25d is output from the orthogonal sampling unit 25e. A Q signal representing an imaginary component is generated by performing low-pass filter processing on the signal series. Thereby, the mixers 25a and 25b shown in FIG. 5 can be omitted.

  Referring to FIG. 2 again, the serialization unit 30 converts the parallel sample data generated by the plurality of channels of the transmission / reception unit 20 into serial sample data. For example, the serialization unit 30 converts 128-channel parallel sample data into 1-4 channel serial sample data. Thereby, compared with the number of the ultrasonic transducers 10, the number of transmission channels is significantly reduced.

  The transmission circuit 50 receives the scanning control signal from the apparatus main body 2, outputs the received scanning control signal to the plurality of transmission / reception units 20, and transmits the serial sample data converted by the serialization unit 30 to the apparatus main body 2. Send. Signal transmission between the ultrasonic probe 1 and the apparatus main body 2 includes, for example, ASK (Amplitude Shift Keying), PSK (Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), and 16QAM (16 Quart Mod Qua quat This is done wirelessly using a method. When using ASK or PSK, it is possible to transmit one channel of serial data with one system. When using QPSK, it is possible to transmit two channels of serial data with one system. When 16QAM is used, four channels of serial data can be transmitted in one system.

  The power supply voltage of the ultrasonic probe 1 is supplied from the apparatus main body 2 when signal transmission between the ultrasonic probe 1 and the apparatus main body 2 is performed in a wired manner, and between the ultrasonic probe 1 and the apparatus main body 2. When signal transmission is performed wirelessly, it is supplied by a battery or the like. When the power supply voltage of the ultrasonic probe 1 is supplied from the apparatus main body 2, phantom power supply may be performed using a signal line connected between the ultrasonic probe 1 and the apparatus main body 2.

  In the above, the quadrature detection processing unit 25 (FIG. 3), the sampling units 26a and 26b (FIG. 3), the time division sampling unit 26c (FIG. 5), the quadrature sampling unit 25e (FIG. 6), the LPFs 25c and 25d (FIG. 6), And the serialization part 30 may be comprised by digital circuits, such as FPGA (Field Programmable Gate Array: The field programmable gate array), and performs various processing to a central processing unit (CPU) and CPU You may comprise by the software (program) for making it.

  When an FPGA, which is a general-purpose circuit, is used, even if the circuit scale is reduced, the number of built-in electronic components is not significantly affected. However, if the circuit scale is reduced, the capacity of the FPGA can be reduced, so that smaller electronic components can be used, which greatly affects the mounting area. Alternatively, the ADC 24 may be omitted by configuring the quadrature detection processing unit 25 with an analog circuit. In that case, A / D conversion of the complex baseband signal is performed by the sampling units 26a and 26b or the time division sampling unit 26c.

  2 includes a transmission circuit 60, a scanning control unit 70, a reception focus processing unit 80, a B-mode image signal generation unit 90, a display unit 100, an operation unit 110, and a control unit. 120 and a storage unit 130.

  The scanning control unit 70 sequentially sets the transmission direction of the ultrasonic beam and generates a scanning control signal. The transmission circuit 60 transmits the scanning control signal generated by the scanning control unit 70 to the ultrasonic probe 1 and receives serial sample data from the ultrasonic probe 1. The scanning control unit 70 sequentially sets the reception direction of the ultrasonic echoes and controls the reception focus processing unit 80.

  The reception focus processing unit 80 performs a reception focus process on the sample data received from the ultrasonic probe 1 to generate a sound ray signal along the ultrasonic reception direction. The reception focus processing unit 80 includes a memory 81 and a phasing addition unit 82. The memory 81 sequentially stores serial sample data received from the ultrasonic probe 1. The phasing addition unit 82 selects one pattern from a plurality of reception delay patterns based on the reception direction set in the scanning control unit 70, and is represented by sample data based on the reception delay pattern. A reception focus process is performed by adding a delay to the complex baseband signal. By this reception focus processing, a baseband signal (sound ray signal) in which the focus of the ultrasonic echo is narrowed is generated.

  The B-mode image signal generation unit 90 generates a B-mode image signal that is tomographic image information regarding the tissue in the subject based on the sound ray signal formed by the reception focus processing unit 80. The B-mode image signal generation unit 90 includes an STC (sensitivity time control) unit 91 and a DSC (digital scan converter) 92. The STC unit 91 corrects attenuation with respect to the sound ray signal formed by the reception focus processing unit 80 according to the depth of the reflection position of the ultrasonic wave. The DSC 92 converts the sound ray signal corrected by the STC unit 91 into an image signal in accordance with a normal television signal scanning method (raster conversion), and performs necessary image processing such as gradation processing to obtain a B-mode image. Generate a signal. The display unit 100 includes a display device such as an LCD, for example, and displays an ultrasound diagnostic image based on the B-mode image signal generated by the B-mode image signal generation unit 90.

  The control unit 120 controls the scanning control unit 70 and the like according to the operation of the operator using the operation unit 110. In the present embodiment, the scanning control unit 70, the phasing addition unit 82, the B-mode image signal generation unit 90, and the control unit 120 cause the central processing unit (CPU) and the CPU to perform various processes. Although configured by software (program), they may be configured by a digital circuit or an analog circuit. The software (program) is stored in the storage unit 130. As a recording medium in the storage unit 130, a flexible disk, MO, MT, RAM, CD-ROM, DVD-ROM, or the like can be used in addition to the built-in hard disk.

  FIG. 8 is a block configuration diagram showing an outline of an internal configuration of an ultrasonic probe according to Modification 1 of the embodiment of the present invention. In the ultrasonic probe 1a shown in FIG. 8, a switching circuit for switching the connection relationship between the plurality of ultrasonic transducers 10 provided in the ultrasonic probe and the transmitting / receiving unit 20 with respect to the ultrasonic probe 1 shown in FIG. 11 has been added.

  In general, in an ultrasonic probe of a linear scan method or a convex scan method, a subject is scanned while the apertures in transmission and reception are sequentially switched. When the number of ultrasonic transducers provided in the ultrasonic probe 1a is N and the number of ultrasonic transducers used at the same time is M (M <N), the switching circuit 11 includes N ultrasonic transducers. M ultrasonic transducers are selected, and the selected M ultrasonic transducers are connected to the M transmitting / receiving units 20, respectively. Thereby, compared with the ultrasonic probe 1 shown in FIG. 2, the number of the transmission / reception parts 20 can be reduced.

  FIG. 9 is a block configuration diagram illustrating an outline of an internal configuration of an ultrasonic probe according to the second modification of the embodiment of the present invention. In the ultrasonic probe 1b shown in FIG. 9, an addition circuit 12 that adds reception signals output from the two ultrasonic transducers 10 at the time of ultrasonic reception is added to the ultrasonic probe 1a shown in FIG. Yes. At the time of ultrasonic transmission, the addition circuit 12 supplies the drive signal supplied from the transmission / reception unit 20 to the two ultrasonic transducers 10 in parallel.

In general, in a linear scan type or convex scan type ultrasonic probe, the transmission / reception direction is perpendicular to the arrangement plane of the ultrasonic transducers, and therefore the delay in transmission / reception is symmetric with respect to the ultrasonic beam. Therefore, in the transmission / reception aperture formed by the M ultrasonic transducers, the delay amount is the same for the first ultrasonic transducer and the Mth ultrasonic transducer, so that the reception signal R ₁ and the reception signal R _M Can be added. Similarly, since the delay amount is the same for the second ultrasonic transducer and the (M−1) th ultrasonic transducer, it is possible to add the received signal R ₂ and the received signal R _(M−1). it can. Thereby, compared with the ultrasonic probe 1a shown in FIG. 7, the number of transmission / reception units 20 can be halved, and the transmission bit rate between the ultrasonic probe 1b and the ultrasonic diagnostic apparatus body 2 can be reduced. Can be halved.

<Description of configuration of ultrasonic probe near ultrasonic transducer>
[Embodiment 1]
FIG. 10A is a side sectional view showing an outline of an internal configuration in the vicinity of the ultrasonic transducer 10 of the ultrasonic probe 1 according to the first embodiment. The ultrasonic probe 1 has a facing surface 3 that faces the patient's diagnosis site P when diagnosing a subject (patient), and a plurality of ultrasonic transducers 10 are connected to the front end portion 10a from the facing surface 3. It is arranged with protruding. The front end portion 10a of the ultrasonic transducer 10 may be provided with a matching layer for absorbing the acoustic impedance difference between the ultrasonic transducer 10 and the diagnostic site P, or an acoustic lens for focusing the ultrasonic waves. It may be provided.

  A plurality of ultrasonic transducers 10 are adjacently arranged in a line along the left-right direction (X direction in the figure) in FIG. 10A. The interval between adjacent ultrasonic transducers 10 is sufficiently small as long as necessary, and no sensor or the like is disposed between the ultrasonic transducers 10 and 10. Therefore, variations in ultrasonic intensity due to the presence of a gap between the ultrasonic transducers 10 and the occurrence of undiagnosable regions are reduced as much as possible.

  The plurality of ultrasonic transducers 10 are held by a holding plate (holding member) 4. FIG. 11 is an enlarged view showing the holding structure of the ultrasonic transducer 10 by the holding plate 4 in an enlarged manner. Through holes 4 a are formed in the holding plate 4 so as to correspond to the ultrasonic transducers 10, respectively. An ultrasonic transducer 10 is fitted into the through-hole 4a, and the ultrasonic transducers 10 can be moved independently along the vertical direction in FIG. 10A (the Y direction in the figure). As a result, the ultrasonic transducer 10 is configured to be able to advance and retract from the opposing surface 3 in a so-called pin relief manner.

  The rear end portion 10 b of the ultrasonic transducer 10 is biased in the advance direction (downward in FIG. 10A) by a spring (biasing means) 5. Therefore, the front end portion 10a of the ultrasonic transducer 10 protrudes from the facing surface 4 in a state where the ultrasonic transducer 10 is always urged in the advance direction. Since the rear end portion 10b is a wide portion larger than the size of the through hole 4a, there is no possibility that the ultrasonic transducer 10 will fall off the holding plate 4 even when urged by the spring 5.

  In FIG. 11, the cross-sectional shape of the ultrasonic transducer 10 (the cross-sectional shape in the direction orthogonal to the advancing / retreating direction) is rectangular, but of course the cross-sectional shape of the ultrasonic transducer 10 can be selected as appropriate. For example, the ultrasonic transducer 10 may have a circular cross-sectional shape as shown in FIG. 12A, or may have a triangular cross-sectional shape as shown in FIG. 12B. Moreover, as shown to FIG. 12C, you may have a hexagonal cross-sectional shape. In order to increase the effective occupied area of the ultrasonic transducer 10 (the ratio occupied by the total cross-sectional area of the ultrasonic transducer 10 out of the predetermined area) as much as possible in the case where they are adjacently arranged in a row, it is necessary to have a polygonal cross-sectional shape. preferable. This can contribute to a reduction in intensity variation of the transmitted ultrasonic waves, and more information on the diagnostic site P can be acquired.

  All of the plurality of ultrasonic transducers 10 are held by the holding plate 4 so as to be movable in the advancing and retreating directions, but each ultrasonic transducer 10 is not affected by the movement of the other ultrasonic transducers 10 and independently. It is configured to be able to advance and retreat. In the first embodiment, the advancing / retreating direction is set to a direction orthogonal to the facing surface 3 (Y direction), and each ultrasonic transducer 10 can advance / retreat in parallel along the Y direction. It has become.

  FIG. 10B is a diagram showing a state in which this ultrasonic probe 1 is brought into contact with a breast including a nipple portion P1 as a diagnostic site P. As shown in FIG. 10B, each ultrasonic transducer 10 is pushed in the retracting direction by the contact of the ultrasonic probe 1, and independently retracts according to the shape (profile) of the diagnostic region P. Therefore, even in the nipple P1 having a locally convex shape, only the corresponding ultrasonic transducer 10 is retracted corresponding to the shape, and the movement of the other ultrasonic transducers 10 is not affected. Even in such a shape of the diagnostic site P, the ultrasonic probe 1 exhibits high shape following ability.

  As shown in FIG. 11, the holding plate 4 is provided with an advance / retreat amount sensor (detection means) 6 for detecting the advance / retreat amount of each ultrasonic transducer 10 for each ultrasonic transducer 10. The advance / retreat amount sensor 6 includes, for example, a known rotary encoder, and the encoder portion 6 a is in contact with the side surface portion 10 c of the ultrasonic transducer 10. The encoder unit 6a rotates as the ultrasonic transducer 10 moves in the advance / retreat direction, so that the rotation of the encoder unit 6a is detected and the advance / retreat amount of the ultrasonic transducer 10 is detected. Then, based on the detected advance / retreat amount of each ultrasonic transducer 10, delay processing in transmission / reception of ultrasonic waves is performed.

  The advance / retreat amount sensor 6 is connected to the probe side control and delay processing unit 40 as shown in FIG. 2, and the detection signal from the advance / retreat amount sensor 6 is a probe side control and delay processing unit that functions as a delay processing unit. 40 is transmitted. The probe-side control and delay processing unit 40 calculates an appropriate delay time for each ultrasonic transducer 10 based on the advance / retreat amount for each ultrasonic transducer 10. This delay time is calculated, for example, as the time required for the ultrasonic wave to propagate a distance corresponding to the relative difference in the advance / retreat amount between the adjacent ultrasonic transducers 10. Then, each transmission / reception unit 20 is driven by adding the delay time based on the advance / retreat amount to the delay time based on the transmission direction set by the scanning control unit 70. As a result, it is possible to correct an error in ultrasonic transmission timing caused by variation in the amount of advance / retreat for each ultrasonic transducer 10.

  On the other hand, when receiving an ultrasonic echo from the diagnostic region P, the signal from the transmission / reception unit 20 is once transmitted to the probe-side control and delay processing unit 40. Then, a delay process based on the amount of advance / retreat for each ultrasonic transducer 10 is performed and transmitted to the serializing unit 30 and transmitted to the apparatus main body 2 side via the transmission circuit 50. Then, the serial signal is transmitted from the transmission circuit 60 in the apparatus main body 2 to the reception focus processing unit 80.

  The phasing addition unit 82 in the reception focus processing unit 80 takes into account the delay time for each ultrasonic transducer 10 calculated by the probe-side control and delay processing unit 40 with respect to the set reception delay pattern, and baseband Generate a signal. Then, the baseband signal is transmitted to the B-mode image signal generation unit (image processing unit) 90, and an echo image is displayed on the display unit 100.

  As described above, when the ultrasonic wave is transmitted and when the ultrasonic echo is received, the delay process based on the advance / retreat amount for each ultrasonic transducer 10 is performed via the probe-side control and delay processing unit 40, thereby causing the advance / retreat amount variation. The timing error caused by the error is corrected, and an appropriate echo image display can be realized.

  The probe-side control and delay processing unit 40 also functions as a profile display unit, and generates a profile (surface shape) of the diagnostic region P based on the detected advance / retreat amount from each advance / retreat amount sensor 6. Then, the generated profile information is transmitted to the apparatus main body 2 side via the serialization unit 30 and the transmission circuit 50, and the profile image of the diagnostic region P is displayed on the display unit 100 of the apparatus main body 2 together with the echo image. It has become.

[Embodiment 2]
FIG. 13 is an external view of the ultrasonic probe 1 according to Embodiment 2 of the present invention. In FIG. 13, the ultrasonic probe 1 is illustrated from the facing surface 3 side. In the ultrasonic probe 1 according to the second embodiment, a plurality of ultrasonic transducers 10 are two-dimensionally arranged adjacent to each other in the X direction and the Z direction. Therefore, the ultrasonic diagnostic apparatus using the ultrasonic probe 1 can be used as an auto-scan type diagnostic apparatus, and not only the ultrasonic cross-sectional image of the diagnostic site P in the specific cross section but also the depth direction (Z direction in the figure). 3D ultrasound diagnostic image having cross-sectional information in the above can be displayed.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these, A various deformation | transformation and change are possible within the range of the summary.

  For example, the ultrasonic probe 1 may be a convex scan type ultrasonic probe in which the opposing surface has a convex shape. In the convex scan type ultrasonic probe, the ultrasonic transducers may be arranged in parallel, and may move forward and backward in parallel with each other. The ultrasonic transducers may be arranged substantially radially so as to be orthogonal to each other, and each ultrasonic transducer may move forward and backward along the radial direction.

  In the above embodiment, the case where the ultrasonic transducer 10 is urged in the advance direction by the spring 5 has been described. However, since the ultrasonic probe 1 is used for diagnosis in most cases with the facing surface 3 facing downward, for example, without using a special member, the ultrasonic transducer 10 uses its own weight as a biasing means in the advancing direction. It may be energized.

  In addition to the rotary encoder described in this embodiment, the advance / retreat amount sensor 4 includes a linear encoder that measures the advance / retreat amount using an encoder attached to the side surface of the ultrasonic transducer, a laser, infrared light, and the like. A length measuring sensor that measures the distance to the rear end portion 10b by receiving light can be used. Further, a distance measuring element that measures the distance to the rear end portion 10b using an ultrasonic wave different from the diagnostic ultrasonic wave can be used as the advance / retreat amount sensor.

  INDUSTRIAL APPLICABILITY The present invention can be used for an ultrasonic diagnostic apparatus that performs imaging of an organ or the like in a living body by transmitting and receiving ultrasonic waves and generates an ultrasonic diagnostic image used for diagnosis.

P: diagnostic part P1: papilla S: ultrasonic diagnostic apparatus X, Y, Z: direction 1: ultrasonic probe (ultrasonic probe)
2: Device body 3: Opposing surface 4: Holding plate (holding member)
4a: Through hole 5: Spring (biasing means)
6: Advance / retreat amount sensor (detection means)
6a: Encoder unit 10: Ultrasonic transducer 10a: Front end portion 10b: Rear end portion 10c: Side surface portion 11: Switching circuit 12: Addition circuit 20: Transmission / reception unit 21: Transmission circuit 22: Preamplifier 23: LPF
24: ADC
25: Quadrature detection processing unit 25a, 25b: Mixer 25c, 25d: LPF
25e: orthogonal sampling units 26a, 26b: sampling unit 26c: time division sampling units 27a-27c: memory 30: serialization unit 40: probe side control and delay processing unit (delay processing unit, profile display unit)
50: transmission circuit 70: scanning control unit 80: reception focus processing unit 81: memory 82: phasing addition unit 90: B-mode image signal generation unit (image processing unit)
91: STC
92: DSC
100: Display unit 110: Operation unit 120: Control unit 130: Storage unit

Claims (8)

An ultrasonic probe for ultrasonic diagnosis, with an opposing surface facing a diagnostic part of a subject, transmitting ultrasonic waves to the diagnostic part and receiving ultrasonic echoes from the diagnostic part,
A plurality of ultrasonic transducers arranged adjacent to each other in a row on the opposing surface to contact the diagnostic site;
The plurality of ultrasonic transducers are
An ultrasonic probe capable of independently moving forward and backward with respect to the facing surface based on contact with the diagnostic region.   The ultrasonic probe according to claim 1, wherein the plurality of transducers can advance and retract along a direction orthogonal to the facing surface.   The ultrasonic probe according to claim 1, wherein the plurality of transducers are two-dimensionally arranged on the facing surface.   The ultrasonic probe according to claim 1, further comprising a biasing unit that biases the plurality of ultrasonic transducers in a direction of advancing from the facing surface.   The ultrasonic probe according to claim 1, further comprising detection means for detecting an advance / retreat amount of the plurality of ultrasonic transducers.   The ultrasonic probe according to claim 1, wherein a cross-sectional shape of the ultrasonic transducer in a direction orthogonal to the advance / retreat direction is a polygonal shape. The ultrasonic probe according to claim 5;
A delay processing unit that performs a delay process based on the amount of advance and retreat of each of the ultrasonic transducers with respect to the ultrasonic echo received by the ultrasonic probe;
An image processing unit for generating an echo image from the ultrasonic echo after the delay processing;
An ultrasonic diagnostic apparatus comprising: a display unit that displays the echo image.   The ultrasonic diagnostic apparatus according to claim 7, further comprising a profile display unit that displays a profile of the diagnostic region on the display unit based on an advance / retreat amount of each of the ultrasonic transducers.

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