JPH06261909A - Ultrasonic thrapeutic device - Google Patents

Abstract

PURPOSE:To prevent ultrasonic misirradiation to a blood vessel and enhance the irradiating efficiency by transmitting pulsated ultrasonic waves, controlling therapeutical ultrasonic waves on the basis of the data established through Doppler analysis of the reflected waves obtained from the pulsated ultrasonic waves received, and extracting the image of the inside of a body. CONSTITUTION:A delay means 10 is controlled by a control device 11, and the driving timing of a pulser group 9 is delayed for a certain time. A received signal delay device 22 selects the reflected waves of the searching ultrasonic waves emitted from a piezo element group 2. The control device 11 is also controlled with signals given by an image processing device 12 and a reflected signal processing device 17. Pulsated ultrasonic waves for image are reflected from an ultrasonic probe 3, and the frequency transition of the reflected pulse waves is processed by an ultrasonic wave Doppler signal processing device 4, and thereby judgement is passed whether a blood stream exists in the neighborhood of the focal position of the intense therapeutic ultrasonic waves. The ultrasonic image acquired by the probe 3 and an MRI image acquired by an MRI device 5 are subjected to signal processing by the image processing device 12 and displayed on an image display device 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic therapeutic apparatus for irradiating ultrasonic waves from outside the body for treatment.

[0002]

2. Description of the Related Art In recent years, as a method of removing stones in the body without surgical operation, a method of crushing and treating stones in the body by focusing intense ultrasonic waves from outside the body has been widely used. It has been attracting attention as a medical application of sound waves. Similarly, as a method for treating a tumor in the body without surgical operation, a method of treating the tumor by heat degeneration by focusing ultrasonic waves from the outside of the body on the tumor site in the body is being studied.

As described above, high-intensity ultrasonic waves are widely applied in the medical field and have great expectations as a future technology, but how to distinguish between a treatment site and a normal tissue other than the treatment site has been a major problem. As described in Japanese Patent Application Laid-Open No. 63-5736, a weak ultrasonic wave for exploration is applied to a high-reflector of ultrasonic waves such as stones so that a reflection signal from a treatment target has a predetermined threshold value. When it is larger than that, it is determined that the focal point of the therapeutic ultrasonic wave coincides with the therapeutic target, and only in that case, the therapeutic ultrasonic wave is irradiated to avoid erroneous irradiation other than the therapeutic target. However, when treating a soft tissue such as a tumor as a therapeutic target, it is difficult to detect the therapeutic target using the reflected wave of the ultrasonic wave for exploration as described above, since the ultrasonic wave is hardly reflected by the soft tissue. 4-4
As shown in Japanese Patent Laid-Open No. 3603, irradiation of therapeutic ultrasonic waves was performed over the entire irradiation range set in advance.

In general, in the treatment of a tumor using high-intensity ultrasound, the focal size of high-intensity ultrasound is much smaller than that of the tumor, and a method of scanning the whole tumor by intensifying high-intensity ultrasound is used. Was there. In an ultrasonic therapy device in which the focus of therapeutic ultrasonic waves is fixed, the applicator is mechanically moved to adjust the ultrasonic focus to the therapeutic target for therapeutic targets having different depths from the body surface. Therefore, there are problems that the treatment time becomes long and the operability of the device is deteriorated, and the patient feels uncomfortable due to multiple contact and friction between the living body and the applicator. In addition, the amount of ultrasonic wave propagation medium (for example, water) between the living body and the ultrasonic wave generation source must be adjusted in accordance with the mechanical movement of the applicator. It has also been pointed out that a problem is that the operability of the device is deteriorated due to the increase of the length. As a means for solving these problems, a method of electronically controlling the focal position of intense ultrasonic waves using a phased array technique has been considered (US Pat. No. 4,526,168). It is believed that the use of this phased array technology eliminates the need for mechanical movement of the applicator and the adjustment of the amount of ultrasonic propagation medium. However, when the focal point is moved electronically, the peak pressure is lowered due to the quantization error caused by the division of the ultrasonic wave generation source, and therefore the focal point movement is proposed as in Japanese Patent Application No. 4-66823. A method has been devised for compensating for the above-mentioned amount of decrease in peak pressure depending on the amount. In addition, in order to efficiently irradiate therapeutic ultrasonic waves when visually scanning the focal point in the tumor and visually confirm the treatment progress, Japanese Patent Application No. 4-4360.
As described in No. 3, a method has been proposed in which therapeutic ultrasonic waves are categorized into a irradiated portion and a non-irradiated portion by different colors.

However, in the treatment of tumors and the like, if major blood vessels in or near the tumor are destroyed, it may cause serious sequelae such as disorders and, in the worst case, it may lead to a life threat. It was required to establish a therapeutic ultrasonic irradiation method that minimizes the damage to the skin. Also,
When the treatment target is a region where the organs that move with breathing, such as the kidney and liver, are the target of treatment, it is difficult to obtain clear images in real time, so it is possible to accidentally irradiate the blood vessels with strong ultrasonic waves. It was very good. When detecting a blood vessel using ultrasonic waves for exploration, the intensity of the reflected wave becomes smaller depending on the in-vivo depth where the blood vessel exists, so keep the threshold constant regardless of the in-vivo depth. There is a problem that it becomes difficult to detect blood vessels.

[0006] On the other hand, in order to accurately execute a treatment plan and perform efficient treatment, the treatment site is visualized so that the unirradiated part and the irradiated part can be clearly understood with respect to the irradiated part of the therapeutic ultrasonic wave. A method of displaying different colors on the screen has been proposed, but when the irradiation is performed multiple times, it is impossible to display according to the number of times, and it is not sufficient as a display of the treatment progress.

As described above, the technique using a phased array is superior in operability in irradiating ultrasonic waves to a wide range of therapeutic targets such as tumors. However, when the focus is moved by the phased array, the focus area energy and the focus size change depending on the focus position. Since the therapeutic effect and the range of the effect are determined by the focus area energy and the focus size, the method of correcting only the decrease amount of the peak pressure is insufficient.

[0008]

In the treatment of tumors and the like, there has been a demand for establishment of a therapeutic ultrasonic irradiation method that minimizes damage to blood vessels. In addition, when the treatment target is a site where the organs such as the kidney that move with breathing repeat,
There was a problem that a powerful ultrasonic wave was accidentally applied to a blood vessel.

Further, in the case of detecting a blood vessel using ultrasonic waves for exploration, the intensity of the reflected wave becomes small depending on the depth in the living body where the blood vessel is present, which makes it difficult to detect the blood vessel. There was a point.

On the other hand, in order to accurately execute the treatment plan and perform efficient treatment, the unirradiated portion and the irradiated portion of the treated ultrasonic wave can be clearly identified. Although a method of displaying different colors on the visualization screen has been proposed, it is not possible to display the treatment progress because it is impossible to display according to the number of times when irradiation is performed multiple times.

Further, in the irradiation of ultrasonic waves to a wide range of treatment targets such as tumors, when the focus is moved when a phased array is used, the focus area energy and the focus size change depending on the focus position. Since the therapeutic effect and the range of the effect are determined by the focus area energy and the focus size, the method of correcting only the decrease amount of the peak pressure is insufficient.

[0012]

In order to solve the above-mentioned conventional problems, the present invention irradiates an object such as a calculus in a patient's body with therapeutic ultrasonic waves from a therapeutic ultrasonic wave generating means and treats it by crushing. In the sound wave treatment apparatus, a probe ultrasonic wave transmitting unit that transmits a probe ultrasonic wave to the vicinity of the object, a reflected wave receiver unit that receives a reflected wave corresponding to the probe ultrasonic wave, and the obtained by this unit The signal processing means for performing Doppler analysis based on the signal, the means for controlling the therapeutic ultrasonic wave generating means based on the data obtained by this means, and the image rendering means for rendering the image inside the patient ultrasound Configure a treatment device.

Further, in an ultrasonic treatment apparatus for irradiating an object such as a stone in a patient's body with therapeutic ultrasonic waves from the therapeutic ultrasonic wave generating means for crush treatment, ultrasonic waves for exploration are transmitted in the vicinity of the object. Ultrasonic wave transmitting means for exploration, reflected wave receiving means for receiving the reflected wave corresponding to the ultrasonic wave for exploration, and reflection intensity detection for detecting the intensity of the reflected wave from near the focus based on the signal obtained by this means Means, means for measuring the distance to the focal position of the therapeutic ultrasonic wave, means for controlling the therapeutic ultrasonic wave generating means based on the reflection intensity and the distance to the focal position, an image inside the patient And an image rendering means for rendering the ultrasonic treatment device.

[0014]

According to the first aspect of the present invention, when a main blood vessel exists within the treatment target, a weak ultrasonic wave for exploration or an ultrasonic signal generated from an ultrasonic probe for diagnosis is used to receive the reflected wave. Then, by analyzing with an ultrasonic Doppler diagnostic apparatus, it is possible to evaluate the frequency shift of the reflected wave and confirm the presence of blood flow. Further, in a relatively uniform parenchymal organ such as the brain or the liver, the reflection from the blood vessel is larger than that in the surroundings. Therefore, by correcting the intensity of the reflected wave with the in-vivo depth and analyzing it, it can be determined whether the blood vessel is a blood vessel. You can judge. When the blood vessel is confirmed as described above, the therapeutic ultrasonic wave is not applied to the site or the ultrasonic wave output is limited.

In the invention relating to image display, the progress of irradiation of therapeutic ultrasonic waves is displayed stepwise according to the number of times of irradiation, so that the treatment plan can be confirmed and the ultrasonic waves can be surely applied. Further, from the blood vessel information acquired by the above invention, the blood vessel is clearly displayed as an irradiation prohibited portion so that the blood vessel is not accidentally irradiated with therapeutic ultrasonic waves. The ultrasonic treatment apparatus according to the present invention does not automatically irradiate therapeutic ultrasonic waves on the irradiation prohibited region.

According to the second aspect of the invention, the change in the focus area energy and the focus size when the focus position is moved is calculated by the calculation means or stored in the storage means.
By changing the focus area energy and the focus movement amount at the time of focus scanning or the focus area energy and the focus size from such information, the irradiation area of the therapeutic ultrasonic waves is uniformly treated without excess or deficiency.

[0017]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing the configuration of an ultrasonic therapeutic apparatus according to the first embodiment of the present invention. In the figure, an ultrasonic applicator 1 is a piezoelectric element group 2 in which a plurality of piezoelectric elements are arranged on a spherical surface.
And an ultrasonic probe 3 for imaging inserted and arranged in the center of the piezoelectric element group 2. As shown in the figure, the applicator 1 treats the treatment target 7 in the body of the patient 6 to the patient 6 via a propagation medium 8 (for example, water) of acoustic energy made of a substance having an acoustic impedance close to that of a living body. Abut.

The piezoelectric element groups 2 can be independently driven and are connected to a pulser group 9 (power pulse generating means). Electric power is supplied to the pulsar group 9 from the high voltage source 14 or the low voltage source 15 via the switching means 16. The delay means 10 is controlled by the control device 11 and delays the drive timing of the pulsar group 9 by an arbitrary time. The reception signal delay device 22 selects a reflected wave from an arbitrary position. Here, the control device 11 is also controlled by signals from the image processing device 12 and the reflection signal processing device 17. The ultrasonic image acquired by the imaging ultrasonic probe 3 and the MRI image acquired by the MRI apparatus 5 are subjected to signal processing by the image processing apparatus 12 and the image display apparatus 1
Displayed by 3.

This device is used to treat a tumor or the like at 70 ° C.
When the device is used as a device or a hyperthermia device that is treated by heating to cause thermal denaturation as described above or a hyperthermia device, the focus is scanned according to the treatment plan. If the focus scanning method uses a two-dimensional array, the focus size and the focus area energy change depending on the focus position. The memory 18 records the focus size and the focus area energy for each focus position set in the two-dimensional array, and the controller 11 is based on the information.
The focus movement amount and the focus area energy are controlled by. That is, when the focal point is scanned over the affected area using the two-dimensional array, the focal point position is not continuously changed but discontinuously according to the focal point size, and at the same time, the energy input to the piezoelectric element group 2 is changed. .

Next, the operation of the present invention will be described with reference to FIG. The focus of the intense ultrasonic wave for treatment is scanned according to the treatment plan while confirming the image of the treatment target acquired in advance or in real time by the MRI apparatus. At that time, it is possible to proceed with the treatment while confirming the treatment target also by the ultrasonic probe 3 for imaging.

Further, the ultrasonic probe 3 for imaging
Emits pulsed ultrasonic waves for imaging,
By processing the frequency shift of the reflected pulse wave by the ultrasonic Doppler signal processing device 4, it is determined whether or not there is blood flow near the focal position of the therapeutic strong ultrasonic wave.
If there is a blood vessel at the focal position, the control device 11 does not radiate strong ultrasonic waves. Further, when there is a blood vessel in the vicinity of the focus position, the controller 11 controls the intensity and irradiation time of the powerful ultrasonic wave for treatment according to the difference in distance between the focus and the blood vessel, so that the blood vessel is not destroyed and the treatment purpose is sufficient Irradiate therapeutic high intensity ultrasound that can be achieved. Here, when the blood flow is flowing perpendicularly to the imaging ultrasonic probe 3, the ultrasonic Doppler signal is not acquired, but the blood vessel travels by rotating the ultrasonic probe or comparing with the MRI image. Can be expected.

In the case of FIG. 1, the existence of blood vessels can be confirmed by generating a weak probe ultrasonic wave from the piezoelectric element group 2 and evaluating the magnitude of the reflected wave and the in-vivo depth. Usually, the blood vessel is a specular reflector, and the reflected wave from the blood vessel is larger than the reflected wave from the soft tissue and smaller than the reflected wave from the high reflector of ultrasonic waves such as stones and gas. The situation is shown in FIG. Now, in order to analyze the reflected wave only in the vicinity of the focus,
As shown in, the reflected wave is cut out in the time window and the reflected wave amplitude is measured. In FIG. 3, a region A is a reflected wave from soft tissue, a region B is a blood vessel, and a region C is a reflected wave from a calculus. Since the reflected wave from the calculus is large as shown by C, it may be considered that it is the reflected wave from the calculus if the reflected wave above a predetermined threshold is obtained, but the reflected wave from the blood vessel is from the soft tissue. It is larger than the reflected wave, but smaller than the reflected wave from the stone.

Further, as shown in FIG. 3, the reflected wave intensity decreases depending on the in-vivo depth. Therefore, if the threshold value is changed depending on the in-vivo depth, the blood vessel and the tumor which is the soft tissue can be distinguished. The means for measuring the depth in the living body is built in the reflection signal processing device 17 here.

Another example will be described as a method of detecting a blood vessel from the intensity of reflected waves. The reflected wave from the blood vessel can be extracted by sampling the intensity of the reflected wave from the vicinity of the focus cut out in a certain time width, calculating the average and variance, and performing statistical processing, which is the blood vessel and soft tissue. It can be distinguished from a tumor. In the case of FIG. 1, the statistical processing of the reflected wave data as described above is performed by the signal processing device 17.

The apparatus can also automatically carry out a treatment plan using MRI images. MRI in advance
A three-dimensional image of the irradiation target is acquired from the image, and is divided into an irradiation region and a non-irradiation region of the intense ultrasonic wave for treatment according to the treatment plan. For example, if the controller 11 is programmed with a keyboard, a mouse, and other input means 19 so as to avoid a thick blood vessel or a thick nerve when treating a tumor in the brain, a focus is obtained using a two-dimensional array. When moving, the therapeutic strong ultrasonic waves are not applied to the blood vessels and nerve parts, or the irradiation intensity and irradiation time are automatically controlled. In that case, it can be combined with the above-mentioned technique of irradiating the blood vessel to avoid irradiation, and a more accurate treatment device is provided.

FIG. 4 shows an image displayed on the image display device 13. (A) is an image acquired by the ultrasonic probe for imaging. In the figure, the dotted line indicates the propagation path 41 of the therapeutic ultrasonic wave, and the square at the tip thereof indicates the focal region 42. (B) is an image acquired by the MRI apparatus. (B) is further divided into two, the one displayed on the left side of the screen is positioned parallel to the scanning plane of the therapeutic high-intensity ultrasound, and the shaded part displayed on the right side of the screen is the screen. Is perpendicular to the left side of. (C) is an image in which the treatment status is color-coded. In the display on the left side of the screen in (c), the portion corresponding to the blood flow is colored 43, so that the direction of the blood flow and the blood flow amount can be visually confirmed. Further, in (c), a color 44 different from the blood flow is attached to the portion scanned with the therapeutic high-intensity ultrasonic waves, and if the therapeutic high-intensity ultrasonic waves are further radiated onto the irradiated portion, the irradiation is performed. The color gradually becomes darker depending on the number of times, and the progress of irradiation of therapeutic strong ultrasonic waves can be immediately confirmed. In the area under irradiation, the color 45 indicating the range is blinking. When coloring the irradiated part, the color is added at once to the range corresponding to the focal size of the intense ultrasonic wave for treatment, so the coloring is performed discontinuously according to the focal size and the focal point movement amount.

FIG. 5 shows a case where the ultrasonic wave propagation medium 8 is a gel-like substance such as ultrasonic jelly. If the gelled ultrasonic wave propagating medium 8 is at room temperature, it causes discomfort when coming into contact with the patient 6. Therefore, it is necessary to warm the ultrasonic wave propagating medium 8 before treatment. In FIG. 5, the bag for maintaining the gel ultrasonic wave propagation medium is composed of the bellows 20 and the membrane 21. The film 21 is made of a substance having an acoustic impedance close to that of a living body, and acoustic energy can be propagated to the living body without waste. The bellows 20 has a heater attached to the inside thereof and has a function of heating the ultrasonic wave propagating substance 8.

FIG. 6 is a diagram showing the configuration of an ultrasonic therapeutic apparatus according to another embodiment of the present invention. In the first embodiment, the ultrasonic Doppler signal is acquired by the imaging ultrasonic probe 3, but the ultrasonic Doppler signal can be acquired by the piezoelectric element group 2 as shown in FIG.
In this case, the reflection signal due to the blood flow of the weak ultrasonic waves for detection generated from the piezoelectric element group 2 is used. The configuration and usage are the same as those in the first embodiment except that the ultrasonic Doppler signal processing device 4 is connected to each piezoelectric element group 2. In FIG. 6, weak piezoelectric ultrasonic waves are emitted from each piezoelectric element, a reflected wave from a certain position is selected by the reception signal delay device 22, and the frequency shift amount of the reflected signal due to the blood flow is reflected by the reflected signal processing device 17. Analyze by. At this time, since the distance and angle between the focal position and each piezoelectric element differ depending on the individual piezoelectric element, each piezoelectric element is weighted when calculating the Doppler shift. Here, since the blood flow direction is vertical when viewed from one piezoelectric element and not vertical when viewed from other piezoelectric elements, there is an advantage that the Doppler signal can be acquired without fail unlike the case of the first embodiment. .
That is, since there is no blind spot, it is possible to accurately avoid the blood vessel and irradiate the intense ultrasonic wave for treatment.

[0029]

As described above, according to the present invention, when the affected area is treated with high-intensity ultrasonic waves, the reflected wave of the ultrasonic waves for exploration is analyzed to examine its frequency shift or intensity. , Detect the presence of blood vessels. At that time, it is possible to treat the affected area without destroying the blood vessel because it is possible to control the irradiation intensity and irradiation time without irradiating the blood vessel site with intense ultrasonic waves for treatment. It is possible to reduce the after-effects and the risk of life due to hemostatic surgery and blood vessel destruction. Further, by changing the display method step by step according to the number of irradiation of the therapeutic ultrasonic waves, it becomes possible to surely implement the treatment plan and confirm the treatment progress.

Further, in a focus movement type ultrasonic therapy apparatus using a phased array, by adding a calculation means or a storage means to control the focus area energy and the focus movement amount, a uniform treatment target can be obtained. The irradiation effect can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an ultrasonic therapeutic apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a reflected wave from a blood vessel obtained by an ultrasonic wave for exploration.

FIG. 3 is a diagram showing reflected wave amplitude with respect to in-vivo depth.

FIG. 4 is a diagram showing a display example of an in-vivo image and treatment progress.

FIG. 5 is a diagram showing a configuration of an applicator.

FIG. 6 is a diagram showing a configuration of an ultrasonic therapeutic apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Ultrasonic applicator 2 ... Piezoelectric element group 3 ... Imaging ultrasonic probe 4 ... Ultrasonic Doppler signal processor 5 ... MRI 6 ... Patient 7 ... Treatment target 8 ... Ultrasonic propagation medium 9 ... Pulsar group 10 ... Delay Means 11 ... Control means 12 ... Image processing device 13 ... Image display device 14 ... High voltage source 15 ... Low voltage source 16 ... Switching means between high voltage source and low voltage source 17 ... Reflection signal processing device 18 ... Storage means 19 ... Input Means 20 ... Bellows and heating means 21 ... Membrane 22 ... Reception signal delay means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mariko Shibata No. 1 Komukai Toshiba Town, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Corporate Research & Development Center, Toshiba Corporation (72) Takuji Suzuki Komukai Toshiba, Kouki-ku, Kawasaki City, Kanagawa Prefecture Town No. 1 Toshiba Corporation Research & Development Center

Claims (4)

[Claims] 1. An ultrasonic treatment apparatus for irradiating therapeutic objects from a therapeutic ultrasonic wave generating means to a target object in a patient body for fragmentation treatment, wherein the probe ultrasonic wave is transmitted to the vicinity of the target object. Sound wave transmitting means, reflected wave receiving means for receiving the reflected wave corresponding to the ultrasonic waves for exploration, signal processing means for performing Doppler analysis based on the signal obtained by this means, and data obtained by this means An ultrasonic therapy apparatus comprising: a means for controlling the therapeutic ultrasonic wave generating means based on the above; and an image drawing means for drawing an image inside the patient. 2. An ultrasonic treatment apparatus for irradiating an object in a patient with therapeutic ultrasonic waves from a therapeutic ultrasonic wave generating means for fragmentation treatment, wherein the ultrasonic probe for exploration transmits ultrasonic waves for exploration in the vicinity of the object. Sound wave transmitting means, reflected wave receiving means for receiving the reflected waves corresponding to the ultrasonic waves for exploration, reflected intensity detecting means for detecting the intensity of reflected waves from the vicinity of the focus based on the signal obtained by this means, Means for measuring the distance to the focal position of the therapeutic ultrasonic wave, and means for controlling the therapeutic ultrasonic wave generating means based on the reflection intensity and the distance to the focal position,
An ultrasonic therapy apparatus comprising: an image drawing means for drawing an image of the inside of the patient. 3. The ultrasonic therapeutic apparatus according to claim 1, wherein the exploratory ultrasonic wave generating means and the reflected wave receiving means are ultrasonic probes for visualizing an in-vivo image. 4. The image rendering means illuminates an object displayed by the means with a means for distinguishing and displaying a portion irradiated with the therapeutic ultrasonic wave and an unirradiated portion, and irradiating the irradiated portion. The ultrasonic treatment apparatus according to claim 1 or 2, comprising means for displaying an identification according to the number of times and means for displaying an irradiation prohibited portion.