WO2013183900A1

WO2013183900A1 - Device and method for eliminating therapeutic ultrasound interference signals during simultaneous ultrasound therapy and diagnosis

Info

Publication number: WO2013183900A1
Application number: PCT/KR2013/004892
Authority: WO
Inventors: 정종섭
Original assignee: 동국대학교 산학협력단
Priority date: 2012-06-04
Filing date: 2013-06-04
Publication date: 2013-12-12
Also published as: KR101357853B1; KR20130136224A

Abstract

The present invention relates to a device and method for eliminating therapeutic ultrasound interference signals during simultaneous ultrasound therapy and diagnosis, comprising a notch filter and a frequency control unit for controlling same, and has the advantages that therapeutic interference signals are eliminated in real time in a simultaneous ultrasound therapeutic and diagnostic system, and not only pulse waves but also continuous waves can be used as therapeutic signals such that ultrasound image quality can be improved to the maximum, and the therapeutic effect and diagnostic performance are kept at the maximum. Also, the invention can be used in all fields in which ultrasound therapy can be attempted while viewing an ultrasound image in real time, including, in particular, benign and malignant tumour therapy, plastic and cosmetic surgery, thrombolysis and haemostasis, drug delivery and cell manipulation.

Description

Apparatus and method for removing ultrasound interference signals for simultaneous ultrasound therapy and diagnosis

The present invention relates to a therapeutic ultrasonic interference signal removal device and method for use in an apparatus and method for simultaneously performing ultrasound treatment and diagnosis.

Recently, the importance of treatment of benign and malignant tumors using non-invasive high intensity focused ultrasound (HIFU) is increasing. In particular, a number of clinical treatments using ultrasound were performed on benign and malignant tumors in the liver, breast, prostate, uterus, etc., and the validity of high-intensity focused ultrasound therapy was verified.

In general, high-intensity focused ultrasound therapy is operated in conjunction with magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound imaging system (US). That is, a method of observing the location, size, and condition of a treatment target, determining an appropriate dose, and irradiating a high-intensity focused ultrasound to the subject using these imaging devices is most commonly used.

These imaging devices provide high-resolution images not only before and after surgery, but also to allow you to observe the real-time treatment process. In addition, the amount of ultrasound irradiation can be adjusted in real time according to the response of the subject under treatment, and the role of observing the movement of the patient or the treated subject is reduced to the maximum degree of damage to the surrounding normal cells.

At present, representative imaging apparatuses used for high-intensity focused ultrasound include magnetic resonance imaging systems and computed tomography systems, but due to their high price, they are relatively inexpensive, occupy less space, and are portable. Interest in imaging devices is increasing.

Meanwhile, one of the most important functions of the high intensity focused ultrasound treatment system should be able to provide high resolution images in real time during surgery. However, there is a great difficulty in implementing such a function in a system for providing a diagnostic image using ultrasound.

In general, a diagnostic ultrasound transducer for implementing an ultrasound image is combined with a therapeutic ultrasound transducer, and simultaneously transmits and receives ultrasound waves for treatment and diagnosis during surgery.

In this case, the diagnostic ultrasonic transducer is received by the diagnostic ultrasonic transducer together with the therapeutic ultrasonic waves (mainly the fundamental frequency signal and the second harmonic) that are reflected and returned as well as the diagnostic ultrasonic signals that are reflected back.

Here, since the intensity of the reflected ultrasound signal for treatment is much larger than that for diagnosis, the image quality of the ultrasound image is greatly deteriorated, and as shown in FIG. 1, an internal image of the human body may be shown without a special interference signal removing technique. (S. Vaezy, X. Shi, R. Martin, E. Chi, PI Nelson, MR Bailey, LA Crum. Ultrasound in Med. & Biol., Vol. 27, pp. 33-42, 2001).

Therefore, various companies and research institutes are developing various methods to provide ultrasound images without interference of therapeutic ultrasound during surgery, and most of these studies have focused on the design of ultrasound transducers. One representative method is to independently combine diagnostic and therapeutic ultrasonic transducers.

FIG. 2 is a diagram illustrating an independent use of a diagnostic ultrasound transducer and a therapeutic ultrasound transducer instead of using a combined ultrasound transducer (S. Burgess, V.Zderic, S. Vaezy, Ultrasound in Med. & Biol., Vol. 33, pp. 113-119, 2007), although there is an advantage that the size of the therapeutic ultrasound signal reflected back by the angle difference between the two transducers is relatively small, the diagnostic ultrasound image Because the ultrasound cannot be transmitted and received on the same plane, it is difficult to focus the ultrasound accurately at the same point, so there is a problem that the treatment target is hard to see, and there is an unsuitable problem in the structure of the endocavity transducer to be inserted into the human body. .

Therefore, in order to simultaneously perform ultrasound diagnosis and treatment, the ultrasonic transducer should have the form of a coupled transducer having the same focal point, and the coupled ultrasonic transducer as shown in FIG. 3 is frequently used (D. Melodelima, WA N`Djin). , H, Parmentier, S. Chesnais, M. Rivoire, JY Chapelon, Ultrasound in Med. & Biol., Vol. 35, pp. 424-435, 2009). However, when using the combined transducer, as described above, the reflected wave of the therapeutic ultrasound is received by the diagnostic ultrasound transducer together with the diagnostic ultrasound, and thus there is a problem that the image quality is degraded due to the interference of the therapeutic ultrasound.

In order to solve this problem, there is a method of increasing the difference between the therapeutic ultrasound frequency and the diagnostic frequency when the transducer is designed to reduce the reflected therapeutic ultrasound signal. There is a limit.

In addition, the most frequently used method is a method of transmitting and receiving the treatment ultrasound and the diagnostic ultrasound alternately with time delay. More specifically, a method of securing the number of repetitions of the diagnostic ultrasound frequency for the minimum image frame and transmitting the therapeutic ultrasound in a section in which the diagnostic ultrasound is not transmitted or received. This method has a disadvantage in that its performance is degraded since the therapeutic ultrasound becomes a pulse wave when frequently transmitting and receiving the diagnostic ultrasound to increase the frame rate of the diagnostic ultrasound image. In practice, ultrasound below a certain duty factor significantly reduces the treatment efficiency. Therefore, in order to secure the ultrasound image frame rate, when the above technique is used only around the subject, there is a problem in that an interference band due to therapeutic ultrasound exists as shown in FIG. 4 (S. Vaezy , X. Shi, RW Martin, E. Chi, PI Nelson, MR Bailey, LA Crum.Ultrasound in Med. & Biol., Vol. 27, pp. 33-42, 2001).

In order to solve the above problems, an object of the present invention is to remove the ultrasonic interference signal for the treatment reflected from the object in the apparatus for performing ultrasound treatment and diagnosis at the same time using the combined ultrasound transducer, ultrasound treatment simultaneously with a high-quality image And it provides a therapeutic ultrasonic interference signal removal device and method configured to make a diagnosis.

In order to achieve the above object, the present invention is a therapeutic ultrasonic interference signal removal device used in a device for simultaneously performing ultrasound treatment and diagnosis, the therapeutic interference in the mixed signal having a therapeutic interference signal and the diagnostic image signal Provided is a therapeutic ultrasonic interference signal removal device comprising a notch filter for removing a signal.

In addition, the present invention in the ultrasonic interference signal removal method used in the apparatus for simultaneously performing the ultrasonic treatment and diagnosis, using a notch filter to remove the therapeutic interference signal from the mixed signal having the therapeutic interference signal and the diagnostic image signal It provides a therapeutic ultrasonic interference signal removal method comprising the step.

The present invention can remove the therapeutic interference signal in real time, and can use not only pulse wave but also continuous wave as the treatment signal, so that the quality of ultrasound image can be maximized and the therapeutic effect and diagnosis performance can be kept to the maximum. There is.

In addition, the present invention has the advantage that can be applied to all fields that can attempt ultrasound treatment while watching the ultrasound image in real time, especially benign and malignant tumor treatment, cosmetic and cosmetic procedures, thrombolysis and hemostasis, drug delivery and cell manipulation have.

1 is a diagram showing a diagnostic ultrasound image before and during irradiation with high-intensity focused ultrasound without a therapeutic ultrasonic interference signal removing device.

2 is an exemplary diagram independently using a therapeutic and diagnostic ultrasonic transducer for ultrasound-based high-intensity focused ultrasound therapy.

3 is a view showing a coupled ultrasound transducer for ultrasound-based high-intensity focused ultrasound therapy.

4 is a diagram showing an ultrasound image before and during high intensity focused ultrasound transmission when the prior art is applied.

5 is a view showing a device for removing a therapeutic interference signal used in the treatment and diagnosis according to the present invention.

6 is a view showing a coupled ultrasonic transducer according to the present invention.

7 is a view showing the structure of the ultrasonic transducer according to the present invention.

8 is a view showing a design of a fixed notch filter according to the present invention.

9 is a diagram illustrating an adaptive notch filter algorithm according to the present invention.

10 is a view comparing the ultrasound image when the therapeutic interference signal removing device according to the present invention is used and not used.

11 is a schematic diagram of a method for canceling a therapeutic interference signal according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, these drawings are for illustrative purposes only, and the present invention is not limited thereto.

5 is a view showing a device for removing a therapeutic interference signal used in the treatment and diagnosis according to the present invention, Figure 6 is a view showing a coupled ultrasonic transducer according to the present invention, Figure 7 is an ultrasound according to the present invention 8 is a view showing the structure of the transformer, Figure 8 is a view showing the design of a fixed notch filter according to the present invention, Figure 9 is a view showing an adaptive notch filter algorithm according to the present invention, Figure 10 is a view of the present invention FIG. 2 is a diagram comparing ultrasound images of a case where a therapeutic interference signal canceller according to the present invention is used and a case where the therapeutic interference signal removing device is not used.

As shown in FIG. 5, the simultaneous ultrasound therapy and diagnostic device using the coupled ultrasound transducer is composed of a therapeutic ultrasound device and a diagnostic ultrasound device.

The simultaneous ultrasound therapy and diagnostic apparatus includes a continuous wave / pulse wave signal generator 10, a transmission beamformer 20, an amplifier 30, a transmitter 40, and a therapeutic ultrasound transducer 50. The system includes a linear / nonlinear pulse wave signal generator 110, a transmit beamformer 120, an amplifier 130, a transmitter 140, a transmit / receive switch 150, an ultrasound transducer 160 for diagnosis, a receiver 170, and a frequency. The controller 300 includes a fixed / adaptive notch filter 350, an amplifier 180, a reception beamformer 190, a signal processor 200, and a display 210.

The continuous wave / pulse wave signal generator 10 generates a signal of continuous wave or pulse wave, and the frequency of the generated continuous wave or pulse wave signal (hereinafter referred to as a therapeutic signal) is lower than the frequency of the diagnostic signal, for example. The center frequency of the diagnostic ultrasound frequency is preferably located between the frequencies of the first harmonic and the second harmonic of the therapeutic signal.

The transmission beamformer 20 focuses the therapeutic signal generated through the continuous wave / pulse wave signal generator 10. The transmission beamformer 20 is used when the therapeutic ultrasonic transducer 50 is an array type, and serves to delay the time of the signal, and changes the focal point of the ultrasonic wave even when the therapeutic ultrasonic transducer 50 is an array type. You can.

The amplifier 30 amplifies the therapeutic signal passed through the transmission beamformer 20. The amplifier 30 preferably includes a band pass filter.

The transmitter 40 transmits the therapeutic signal amplified by the amplifier wirelessly or wired to the ultrasonic transducer 50.

The therapeutic ultrasound transducer 50 may convert the transmitted therapeutic signal into ultrasound to irradiate the therapeutic ultrasound to the subject, and the therapeutic ultrasound may be a high intensity focused ultrasound. The combined ultrasound transducer may have an ultrasound transducer of a model as shown in FIG. 6, and the therapeutic ultrasound transducer 50 may have a single element, a one-dimensional array structure, or a two-dimensional array structure. In addition, the therapeutic ultrasonic transducer 50 may have a piezoelectric element or a piezoelectric element combined with a matching layer without a matching layer and a back layer as shown in FIG. 7, and may have a different stacked structure from the diagnostic ultrasonic transducer 160. Can have.

The linear / nonlinear pulse wave signal generator 110 generates a linear or nonlinear pulse wave signal (hereinafter referred to as a diagnostic signal), and the center frequency of the diagnostic signal is between 1 harmonic and 2 harmonics of the frequency of the therapeutic signal. It is desirable to have a frequency.

The transmission beamformer 120 focuses the diagnostic signal generated through the linear / nonlinear pulse wave signal generator 110. The transmission beamformer 120 is used when the diagnostic ultrasound transducer 160 is an array type, and serves to delay the time of a signal, and may change the focal point of the ultrasound even when the diagnostic ultrasound transducer 160 is an array type. have.

The amplifier 130 amplifies the magnitude of the diagnostic signal focused through the transmission beamformer 120. The amplifier may comprise a band pass filter.

The transmitter 140 transmits the diagnostic signal amplified through the amplifier 130 to the transmission / reception switch 150 wirelessly or by wire.

The transmission / reception switch 150 performs a function of transmitting the transmitted diagnostic signal to the diagnostic ultrasound transducer 160 in a transmission mode, and receives a diagnostic image signal reflected from an object in a reception mode. At this time, the diagnostic image signal is transmitted by mixing with the therapeutic interference signal.

The diagnostic ultrasound transducer 160 converts the diagnostic signal into ultrasound, irradiates the object, and converts the diagnostic ultrasound reflected from the observed object into a diagnostic image signal. At this time, the therapeutic ultrasonic interference signal reflected from the object is also received. Hereinafter, an ultrasonic wave in which the therapeutic ultrasonic interference signal reflected from the object and the diagnostic ultrasonic wave for the ultrasound image reflected from the object are mixed is referred to as a mixed ultrasonic wave, and the signal in which the mixed ultrasonic wave is converted into an electrical signal is referred to as a mixed signal.

The diagnostic ultrasound transducer 160 is preferably a combined ultrasound transducer present in one object in combination with the therapeutic ultrasound transducer 50, and the combined ultrasound transducer is an ultrasound transducer of a model as shown in FIG. It can be The combined ultrasound transducer of FIG. 6 can be miniaturized. As shown in FIG. 6, the combined ultrasound transducer may have a circular, cross, and quadrangular structure, and the position of the therapeutic ultrasound transducer 50 and the diagnostic ultrasound transducer 160 may be changed. In particular, the diagnostic ultrasound transducer 160 may have a one-dimensional or two-dimensional array structure, and the therapeutic ultrasound transducer may have a single element type, a one-dimensional or two-dimensional array structure. When the therapeutic ultrasonic interference signal removing device of the present invention is used in an apparatus for simultaneously performing ultrasound therapy and diagnosis, a high-quality ultrasound diagnosis image may be provided even when the combined ultrasound transducer is used.

In addition, the therapeutic ultrasonic transducer 50 may have only a piezoelectric element, or a piezoelectric element combined with a matching layer, as shown in FIG. 7, and may have a different stacked structure from the diagnostic ultrasonic transducer 160.

The mixed signal may be transmitted to the receiver in the reception mode of the transmission / reception switch 150, and the receiver 170 may transmit the mixed signal to the notch filter 350 or the frequency controller 300 by wireless or wired.

The notch filter 350 functions to remove one harmonic and two harmonics of the therapeutic interference signal from the mixed signal transmitted from the frequency controller or the receiver 170. Two notch filters may be connected in series to remove the harmonics, but the present invention is not limited thereto, and it is apparent to those skilled in the art that all kinds of band removing filters capable of removing the frequency are equivalents of the notch filter 350. something to do.

The notch filter 350 may use a fixed notch filter or an adaptive notch filter. As shown in FIG. 8, the fixed notch filter functions to remove a fixed magnitude value (dB) at the center frequency. For example, the removal gain of the notch filter 350 is fixed to a specific value. In addition, the fixed notch filter preferably has a high quality factor (Q).

The notch filter 350 may be an adaptive notch filter. The adaptive notch filter does not have a fixed cancellation gain and, through feedback, functions to track and remove until the therapeutic interference signal magnitude is completely removed.

The adaptive notch filter is preferably an adaptive notch filter having an algorithm as shown in FIG. 9 and Equation 1 below.

[Equation 1]

y (k) = W ^T (k) r (k)

e (k) = p (k) -y (k)

W (k + 1) = W (k) + βe (k) r (k)

In FIG. 9 and Equation 1, the input signal p (k) is the sum of the reflected diagnostic image signal s (k) and the therapeutic interference signal n (k), and e (k) is an error signal and a reference signal. Is r (k) and the final output signal is s (k).

When the notch filter 350 is used, the center frequency of the diagnostic ultrasound or diagnostic image signal is positioned at the center between 1 harmonic and 2 harmonics of the frequency of the therapeutic interference signal, thereby maximizing the available rental width of the diagnostic ultrasound transducer 160. Can be increased. That is, when the frequency of the therapeutic ultrasound is 4MHz, the diagnostic ultrasound frequency is 6MHz and is located at the centers of the 1 harmonic frequency (4MHz) and the 2nd harmonic frequency (8MHz) of the therapy ultrasound. In this case, the 6dB rental width is 67% ((8MHz-4MHz) / 6MHz) to design the broadband diagnostic ultrasound transducer 160.

The frequency controller 300 functions to adjust the center frequency of the notch filter 350 by analyzing the frequency of the interference signal for treatment of the mixed signal transmitted from the receiver 170. Since the frequency of the therapeutic signal generated from the continuous therapeutic wave / pulse wave signal generator 10 for treatment and the frequency of the therapeutic interference signal portion of the mixed signal reflected back are different from each other, the center frequency of the notch filter 350 is determined. Perform the function to adjust. For example, if the signal generator generates a frequency of a 4 MHz therapeutic signal, the first harmonic of the frequency of the therapeutic interference signal reflected and returned due to an error, etc. may be 4.2 MHz, and the second harmonic is 8.4 MHz. have. If the center frequency is set to 4 MHz and 8 MHz in the notch filter 350 for removing the interference signal of the therapeutic ultrasound, the electrical signal cannot be effectively removed. Therefore, the frequency controller 300 serves to match the center frequency of the notch filter 350 with one harmonic and two harmonics of the actually received therapeutic interference signal.

The frequency controller 300 includes a fast Fourier transform unit 310, a frequency detector 320, a band pass filter 330, and a transmit and receive frequency comparator 340.

The fast Fourier transform unit 310 provides the mixed signal received from the receiver 170 for each frequency (first harmonic, second harmonic, Nth harmonic) in the frequency domain through Fourier transform.

The frequency detector 320 may read the frequency information of the received mixed signal by using the information provided by the fast Fourier transform unit 310 to determine whether the therapeutic ultrasound is actually transmitted properly. It is possible to determine the magnitude of the therapeutic ultrasound signal for each frequency. The cutoff frequency and the rental width of the band pass filter 330 may be adjusted based on the identified frequency and magnitude.

The band pass filter 330 removes frequencies of three harmonics or more of the interference signal for treatment of the mixed signal passed through the frequency detector 320.

When the band pass filter 330 removes 1 harmonic and 2 harmonics of the therapeutic interference signal, the bandpass filter 330 also removes a diagnostic image signal having important diagnostic image information around 1 harmonic and 2 harmonics of the therapeutic interference signal. It is not suitable for the purpose of removing the therapeutic interference signal while protecting the image information as much as possible.

The transmission and reception frequency comparator 340 is a treatment in which the continuous / pulse wave signal generator 10 of the ultrasonic apparatus for the treatment actually generates the first harmonic and the second harmonic signal of the mixed signal from which harmonics of at least three harmonics of the therapeutic interference signal are removed. The change amount is measured in comparison with the frequency of the dragon signal, and the frequency control unit 300 applies the fixed / adaptive notch filter 350 as the changed reference signal of the fixed / adaptive notch filter 350.

More specifically, the frequency controller 300 controls to change the center frequency of the notch filter 350 to frequencies of 1 harmonic and 2 harmonics of the actually received therapeutic interference signal. For example, if the frequency of the therapeutic electrical signal transmitted by the signal generator of the actual therapeutic ultrasound system is 4 MHz, a frequency of 1 harmonic of 5 MHz and 2 harmonics of 10 MHz of the received therapeutic interference signal is 10 MHz. Therefore, by applying the reference signal of the notch filter 350 through the transmission and reception frequency comparator 340 to change the center frequency to 5MHz and 10MHz.

The mixed signal passing through the transmission and reception frequency comparator 340 is removed by the notch filter 350 to remove the therapeutic interference signal, and the diagnostic image signal is amplified by the amplifier 180.

The reception beamformer 190 focuses the amplified diagnostic image signal.

The signal processor 200 processes a signal to image the diagnostic image signal, and the display 210 images an object based on the processed signal.

10 (a), (b) and (c) are diagrams showing a case of using and not using a therapeutic ultrasonic interference signal removing device according to the present invention.

10 (a) shows that the image is high quality when only the ultrasound diagnosis is performed.

FIG. 10 (b) shows that when the ultrasound therapy equipment is operated simultaneously for the treatment of tumor while performing the ultrasound diagnosis in real time, the reflected high intensity therapy ultrasound signal is mixed with the diagnosis ultrasound signal and simultaneously received by the diagnostic transducer. This indicates that the performance of image quality is degraded.

10 (c) shows that the image is converted to high quality when the therapeutic ultrasonic interference signal removing device according to the present invention is used.

Hereinafter, a method of removing the ultrasonic interference signal for treatment will be described with reference to FIG. 11.

The therapeutic ultrasonic interference signal removing method of the present invention includes the steps of removing one harmonic and two harmonics of the therapeutic interference signal using a fixed or adaptive notch filter. The center frequency of the fixed or adaptive notch filter may be adjusted to have frequencies of 1 harmonic and 2 harmonics of the therapeutic interference signal through a frequency controller.

More specifically, the process of adjusting the center frequency of the fixed or adaptive notch filter through the frequency control unit provides frequency and magnitude information of the mixed signal to the frequency detector using the fast Fourier transform unit (110), and the frequency detector Read the information provided in the step (S110), and adjust the cutoff frequency and bandwidth of the band pass filter by using the magnitude and frequency information of the therapeutic ultrasonic interference signal (S120), the step of (S120) Using a band pass filter having a cutoff frequency and a bandwidth, a signal having a frequency of 3 harmonics or more of the therapeutic interference signal of the mixed signal is removed (S130). Pulse / continuous wave signal generator using the transmit and receive frequency comparators in the step (S130) of the mixed signal from which the therapeutic interference signal having a frequency of 3 harmonics or more is removed. Comparing the frequency of the signal generated through and measuring the amount of change of the frequency (S140), and the process of changing the center frequency of the fixed or adaptive notch filter to 1 harmonic and 2 harmonic frequencies of the therapeutic interference signal (S180) do.

The therapeutic interference signal of the mixed signal is generated through the following process.

After generating a therapeutic signal of a predetermined frequency from the continuous wave / pulse wave signal generator 10, the therapeutic signal is focused on the transmission core beamformer 20, and the amplifier is amplified and the therapeutic signal is transmitted. The therapeutic signal is transmitted to the therapeutic ultrasonic transducer 40 through 40. The therapeutic signal is converted into therapeutic ultrasound through the therapeutic ultrasound transducer 50 and irradiated to the object. The therapeutic ultrasound that is irradiated to the object and reflected is converted into an electrical signal through a diagnostic ultrasound transducer, which is called a therapeutic interference signal. The therapeutic interference signal is transmitted to the receiver in the reception mode of the transmission and reception switch 150 and then applied to the frequency controller 300 or the fixed or adaptive notch filter 350 at the receiver.

The diagnostic image signal of the mixed signal is generated through the following process.

After generating a diagnostic signal having a center frequency located in the middle of the frequency of one harmonic and two harmonics of the therapeutic signal from the linear / nonlinear pulse wave signal generator 110, the diagnostic signal is focused on the transmission beamformer 120. The amplifier 130 amplifies the diagnostic signal. The amplified diagnostic signal is transmitted to the transmission / reception switch 150 through the transmitter 140, and the diagnostic signal is converted into therapeutic ultrasound through the diagnostic ultrasound transducer 160 and irradiated to the object. The irradiated diagnostic ultrasound is converted into an electrical signal by the diagnostic ultrasound transducer 160, which is called a diagnostic image signal. The diagnostic image signal is transmitted to the receiver 170 in the reception mode of the transmission / reception switch 150 and applied to the frequency controller or the fixed / adaptive notch filter 350 through the receiver.

As mentioned above, preferred embodiments of the present invention described above are disclosed for the purpose of illustration, and those skilled in the art can improve other various embodiments within the spirit and technical scope of the present invention disclosed in the appended claims below. Changes, substitutions or additions will be possible.

[부호의 설명][Description of the code]

10: Continuous / Pulse Wave Signal Generator

20: transmission beamformer (therapeutic ultrasonic device)

30: amplifier

40: transmitter

50: therapeutic ultrasonic transducer

110: linear / nonlinear pulse wave generator

120: transmission beamformer (diagnostic ultrasonic apparatus)

130: amplifier

140: transmitter

150: transmit and receive switch

160: diagnostic ultrasonic transducer

170: receiver

180: amplifier

190: reception beamformer

200: signal processing unit

210: display

300: frequency control unit

310: fast Fourier transform unit

320: frequency detector

330 band pass filter

340: transmit and receive frequency comparators

350: fixed / adaptive notch filter

Claims

In the therapeutic ultrasonic interference signal removal device used in the apparatus for performing ultrasound treatment and diagnosis at the same time,

And a notch filter for removing the therapeutic interference signal from the mixed signal having the therapeutic interference signal and the diagnostic image signal.
The method of claim 1,

And a frequency control unit for controlling the center frequency of the notch filter to have frequencies of 1 harmonic and 2 harmonics of the therapeutic interference signal.
The method of claim 2,

The frequency control unit includes a fast Fourier transform unit for providing frequency information on the mixed signal having a therapeutic ultrasonic interference signal and a diagnostic image signal;

A frequency detector for reading frequency and magnitude information of the therapeutic interference signal provided by the fast Fourier transform unit to adjust a cutoff frequency and a bandwidth of the band pass filter;

A band pass filter for removing harmonics of at least three harmonics of the therapeutic ultrasonic interference signal using a cutoff frequency and a bandwidth adjusted by the frequency detector; And

The center frequency of the notch filter is changed to the frequency of the therapeutic interference signal by measuring the amount of change of the frequency by comparing the therapeutic interference signal among the mixed signals passing through the band pass filter with the frequency of the treatment signal generated by the continuous wave / pulse wave signal generator. Transmitting and receiving frequency comparator to the; characterized in that, comprising a therapeutic ultrasonic interference signal removal device.
The method of claim 1,

And the notch filter is an adaptive notch filter or a fixed notch filter.
The method of claim 1,

The mixed signal is characterized in that after the therapeutic ultrasound and diagnostic ultrasound from the therapeutic ultrasound device and the diagnostic ultrasound device irradiated to the object, the mixed ultrasound reflected from the object is converted into an electrical signal through the diagnostic ultrasound transducer, Ultrasonic Interference Canceling Device.
The method according to claim 1 or 2,

The apparatus for simultaneously performing ultrasound treatment and diagnosis,

A continuous wave / pulse wave signal generator for generating a therapeutic signal having a therapeutic continuous wave or pulse wave;

A transmission beamformer that focuses the therapeutic signal;

An amplifier for amplifying the focused therapeutic signal;

A transmitter for transmitting the amplified therapeutic signal to a therapeutic ultrasonic transducer;

A therapeutic ultrasound transducer for converting the therapeutic signal transmitted by the transmitter into therapeutic ultrasound to irradiate the object;

A linear / nonlinear signal generator for generating a diagnostic signal having a diagnostic linear or nonlinear pulse wave;

A transmission beamformer that focuses the diagnostic signal;

An amplifier for amplifying the focused diagnostic signal;

A transmitter for transmitting the amplified diagnostic signal to a transmission / reception switch;

A transmission / reception switch for transmitting the diagnostic signal to a diagnostic ultrasound transducer in a transmission mode and transmitting a mixed signal reflected from an object in a reception mode to a receiver;

A diagnostic ultrasound transducer for converting the diagnostic signal transmitted by the transmission / reception switch into diagnostic ultrasound and converting the mixed ultrasound reflected from the object into an electrical signal;

A receiving unit for receiving the mixed signal reflected from the object and converted by the diagnostic ultrasonic transducer from a transmission / reception switch and transmitting to the therapeutic interference signal removing device of claim 1 or the therapeutic interference signal removing device of claim 2;

An amplifier for amplifying the diagnostic image signal from which the therapeutic interference signal has been removed;

A signal processor that processes the signal to enable imaging of the diagnostic image signal amplified by the amplifier; And

And a display for imaging the processed diagnostic image signal.
The apparatus of claim 6, wherein the diagnostic ultrasound transducer irradiates the object with a diagnostic ultrasound having a frequency located at a center between one harmonic and two harmonics of the therapeutic interference signal. .
The apparatus of claim 6, wherein the diagnostic ultrasonic transducer and the therapeutic ultrasonic transducer are combined ultrasonic transducers positioned in one object.
The apparatus of claim 8, wherein the combined ultrasound transducer is any one of a circular structure, a cross-shaped structure, and a rectangular structure.
The method of claim 9, wherein the therapeutic ultrasonic transducer of the combined ultrasonic transducer has a single element, a one-dimensional array structure or a two-dimensional array structure, the diagnostic ultrasonic transducer has a one-dimensional or two-dimensional array structure, Ultrasonic interference signal removal device for treatment.
In the ultrasonic interference signal removal method used in the apparatus for performing ultrasound treatment and diagnosis at the same time,

1) removing the therapeutic interference signal from the mixed signal having the therapeutic interference signal and the diagnostic image signal by using a notch filter.
The method of claim 11,

2) the notch filter includes a step of controlling the center frequency under the control of the frequency control unit to have frequencies of 1 harmonic and 2 harmonics of the therapeutic interference signal,

2-1) providing frequency and magnitude information of the mixed signal to the frequency detector by using a fast Fourier transform unit;

2-2) reading the information provided in step 2-1) using a frequency detector, and adjusting the cutoff frequency and bandwidth of the band pass filter by using the magnitude and frequency information of the therapeutic ultrasonic interference signal;

2-3) removing a signal having a frequency of at least three harmonics of the therapeutic interference signal of the mixed signal by using a band pass filter having the cutoff frequency and the bandwidth of the step 2-2); And

2-4) Using the transmitting and receiving frequency comparator, the frequency of the first harmonic and the second harmonic of the therapeutic interference signal among the mixed signals from which the therapeutic interference signal having a frequency of 3 harmonics or more is removed in step 2-3) Comparing the frequency of the treatment signal generated through the spar / continuous wave generator, measuring the amount of change in frequency, and changing the center frequency of the fixed or adaptive notch filter to one harmonic and two harmonic frequencies of the treatment interference signal; Included, the therapeutic ultrasonic interference signal removal method.
The method of claim 12,

And the notch filter is an adaptive notch filter or a fixed notch filter.