JPH11226046A - Ultrasonic wave treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic wave treatment device for simplifying the control of focus movement and irradiation, shortening treatment time and substantially improving the uniformity of energy distribution. SOLUTION: This ultrasonic wave treatment device is provided with an ultrasonic-wave-for-treatment generation source 2, an RF amplifier 14 for driving the ultrasonic-wave-for-treatment generation source so as to generate ultrasonic waves for treatment, a stage 21 for moving the focus of the ultrasonic waves for the treatment and a system controller 9 for controlling the RF amplifier 14 and the stage 21 so as to perform continuous irradiation with the ultrasonic waves for the treatment while continuously moving the focus of the ultrasonic waves for the treatment along a track covering a lesion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic treatment apparatus for treating a tumor or the like in a living body using ultrasonic waves.

[0002]

2. Description of the Related Art In recent years, MIT (Minimally I
The flow of minimally invasive treatment called nvasive treatment has attracted attention in various medical fields. One example is the practical application of a calculus crushing device that crushes calculi non-invasively by irradiating intense ultrasonic waves from outside the body for the treatment of calculi, and has greatly changed the treatment method for urinary calculi. The powerful ultrasonic sources used in this calculus crusher include underwater discharge, electromagnetic induction, micro explosion,
There are disadvantages such as the piezo method, and the piezo method has the disadvantage that the pressure of the powerful ultrasonic wave is small.However, there is no small focus, no consumables, the powerful ultrasonic pressure can be arbitrarily controlled, There is a unique advantage that the focus position can be arbitrarily controlled by controlling the phase.

[0003] In particular, in the case of malignant neoplasms, so-called cancers, since the treatment of many of them depends on surgical techniques, the functions and appearance of the organs are greatly impaired in many cases. . For this reason, even if the life is prolonged, a large burden remains on the patient.
There is a strong demand for the development of a less invasive treatment method (apparatus) in consideration of (Quality Of Life).

[0004] Conventionally, surgical resection, radiation therapy, and chemotherapy (anticancer drugs) are the three major therapies for cancer. In the course of the above-mentioned minimally invasive treatment, heat is one of the new cancer treatment techniques. Therapies used have come to the fore. A prominent example is hyperthermia therapy. This takes advantage of the difference in heat sensitivity between tumor tissue and normal tissue,
This is a treatment method in which only the cancer cells are selectively killed by heating the affected area to 42.5 to 43 degrees or more and maintaining it for a certain period of time.

[0005] As a method of heating, a method using electromagnetic waves such as microwaves has been preceded. However, in this method, it is difficult to selectively heat a deep tumor due to the electrical characteristics of a living body. Good therapeutic results cannot be expected for tumors of 5 cm or more.

In recent years, a microwave / RF wave antenna has been inserted into a diseased part intraoperatively, laparoscopically or percutaneously, and the temperature around the antenna has been raised to 60 ° C. or more in order to improve the poor penetration of electromagnetic energy. A new therapeutic method that has improved the local therapeutic effect by heating at a high temperature has been spotlighted (Isota et al .: J. Microwave Surgery). However, since this treatment also requires puncture of an organ, it is less invasive than conventional surgical treatment, but also has a problem in that there are side effects such as bleeding and dissemination (metastasis) associated with puncture.

In order to solve these problems, attention has been paid to a method of performing heat treatment of a deep tumor from outside the body using ultrasonic energy having a good energy focusing property and a high degree of penetration.

Further, the above-mentioned heating treatment method is further advanced, and the ultrasonic wave generated by the piezo element is sharply focused on the affected part to heat the tumor portion to 80 ° C. or more, and the tumor tissue is instantaneously thermally denatured and necrotic. Treatments are also being considered (G. Wall
ancien et. al: Progress in
Urol. 1991, 1, 84-88 [EDAP company paper]).

In the present treatment method, unlike conventional hyperthermia, an ultrasonic wave of very strong energy (several hundreds to several thousand W / cm ² ) is applied to a localized area near the focal point, so that the area near the focal point is narrow. Only the area is instantaneously heat denatured and necrotic. In addition, since it is necessary to cauterize the entire affected area while scanning the small focal point, accurate positioning of the focal point is considered to be very important. As one solution to this, a technique of measuring an intraoperative heat point by noninvasive temperature distribution imaging in the body using a chemical shift of MRI (magnetic resonance imaging) is disclosed. Further, even in a system using only an ultrasonic wave, a method of detecting a reflected wave from a focal region of a therapeutic ultrasonic wave and displaying the detected ultrasonic wave on an ultrasonic image has been considered.

[0010]

As described above, the conventional high-intensity ultrasonic treatment apparatus can focus very sharply. However, since the focal point is small, the focal position must be adjusted in order to cauterize a relatively large affected part. In particular, in the treatment of a large tumor, the control of the focal point and the irradiation are not only very complicated, but also have a drawback that the treatment time is prolonged, because it is necessary to repeat irradiation.

Further, in the conventional method, since the ultrasonic energy is very limited, excessive heat is generated in the focal region due to too strong ultrasonic intensity, and sufficient heat is generated immediately in the vicinity thereof. For example, the energy distribution became very uneven, and the cauterization was uneven.

It is an object of the present invention to provide an ultrasonic treatment apparatus in which the control of the movement of the focal point and the irradiation is simplified, the treatment time is shortened, and the uniformity of the energy distribution can be significantly improved. is there.

[0013]

According to a first aspect of the present invention, there is provided an ultrasonic therapy apparatus, comprising: a source of a therapeutic ultrasonic wave; and the ultrasonic source for generating a therapeutic ultrasonic wave. A driving unit that drives a sound wave source, a focus moving unit that moves a focal point of the treatment ultrasonic wave, and the focus unit that continuously moves the focal point of the treatment ultrasonic wave along a trajectory that covers the object to be treated. The apparatus further comprises control means for controlling the driving means and the focal point moving means so as to continuously emit therapeutic ultrasonic waves.

According to a second aspect of the present invention, there is provided an ultrasonic therapeutic apparatus comprising: a therapeutic ultrasonic generating source; and a therapeutic ultrasonic generating source for generating therapeutic ultrasonic waves. Driving means for driving, focus moving means for moving the focal point of the treatment ultrasonic wave, and treating the whole treatment object while moving the focal point of the treatment ultrasonic wave along a trajectory covering the treatment object. At this time, control for controlling the driving unit and the focal point moving unit so that a section for continuously irradiating the therapeutic ultrasonic waves while continuously moving the focal point is included in at least a part of the trajectory. Means.

Further, according to a third aspect of the present invention, there is provided an ultrasonic treatment apparatus comprising: a treatment ultrasonic generation source; and a treatment ultrasonic generation source for generating treatment ultrasonic waves. A driving means for driving, a focus moving means for moving a focal point of the treatment ultrasonic wave, and a treatment target or a treatment target while continuously moving the focal point of the treatment ultrasonic wave along a predetermined trajectory. Control means for controlling the driving means and the focal point moving means so as to alternately repeat the continuous irradiation and stop of the therapeutic ultrasonic waves in accordance with the shape of the region. According to the present invention, the focal point of the therapeutic ultrasonic wave moves continuously along the trajectory covering the object to be treated, and the therapeutic ultrasonic wave continuously changes. Irradiated. In this way, since it is only necessary to combine the continuous movement of the focal point and the continuous irradiation of the therapeutic ultrasonic waves, the conventional method of intermittently moving the focal point and repeating the irradiation of the therapeutic ultrasonic waves in synchronization with it The focus movement and the control of the irradiation are simplified, and the treatment time is greatly reduced, as compared with the complicated movement of. Furthermore, since the therapeutic ultrasound is continuously emitted while the focal point moves continuously, it is possible to disperse the spatial bias of energy, make the energy distribution much more uniform, and reduce cauterization unevenness. it can.

The combined movement of the continuous movement of the focal point and the continuous irradiation of the therapeutic ultrasound does not apply to the entire trajectory covering the object to be treated.
As shown in the above, it is effective to carry out only a part of the track.

Furthermore, by moving the focal point in the same trajectory and controlling the continuous irradiation of the therapeutic ultrasonic waves and the stop thereof in response to the focal points, the object having various shapes can be obtained. The treatment can be effectively and efficiently advanced for the treatment object.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a configuration of an ultrasonic therapy apparatus according to the present embodiment. The therapeutic ultrasonic wave source 2 is attached to the frame 12 of the applicator 1. Ultrasound source for treatment 2
, A piezo element or a piezo element group that generates powerful ultrasonic waves is provided in a spherical shell shape. At the geometric center of the spherical shell, therapeutic ultrasonic waves generated from the piezo element are focused. A region showing the energy of a certain level or more around the focal point is generally referred to as a focal point 8. The focal point 8 has a diameter of 10 mm and a length of 15 m, for example.
m.

A substantially central portion of the frame 12 and the ultrasonic generating source 2 for treatment is cut out, and an ultrasonic probe 16 for cylindrical imaging is inserted therein. The ultrasonic diagnostic apparatus 17 scans the vicinity of the focal point 8 with an ultrasonic wave via the ultrasonic probe 16 to generate a tomographic image and displays it on a CRT 19 via a digital scan converter (DSC) 18. Is provided.
The tomographic image displayed on the CRT 19 is superimposed with a focus marker indicating a focal point, a graphic such as an ablation region input via the console panel 10, and other character information, and is displayed on the CRT 19. Has become.

Under the therapeutic ultrasonic wave generator 2 and the ultrasonic probe 16, the therapeutic ultrasonic waves and the ultrasonic waves for imaging are guided to the patient's body surface with less loss, and the reflected waves from the inside of the patient are reduced with less loss. The coupling liquid 4 for leading to the ultrasonic probe 16 is filled in the coupling film 5.

The applicator 1 is attached to the end of an arm 22 extending from the stage 21 on the frame 12, and is free to any position, even within a limited space centered on the stage 21. It can move to and can stand still in any posture. This arm 2
The movement of 2 is completely controlled by the stage controller 20 under the control of the system controller 9.

During treatment, the patient is first placed on a bed (not shown).
And fixed at a predetermined position. And applicator 1
Is brought into contact with the patient's body surface coated with ultrasonic jelly or the like (not shown) from the coupling film 5. When a high-frequency signal in the ultrasonic range is generated from the continuous wave generation circuit 11 in accordance with a control signal from the system controller 9, the high-frequency signal is amplified by the RF amplifier 14, and passed through the impedance matching circuit 15. It is supplied to the piezo element of the sound source 2. Thereby, the piezo element vibrates mechanically to generate ultrasonic waves. This ultrasonic wave is guided into the patient via the coupling liquid 4, forms a focal point 8, and heats an affected part (tumor) at the focal point 8.

Here, in the conventional thermal treatment using focused ultrasound, one shot of about 1 second has a diameter of 2 mm and a length of 10 mm.
Cauterizing the affected area within the focal area, but cauterizing the entire affected area requires shifting the focal position a little, stopping the focal point at this position, and then shooting and repeating such movements. I have. This is, as described in the prior art, difficult to control because of the prolonged treatment time and the precise synchronization of the intermittent movement of the focus and the short-time irradiation (shot) of therapeutic ultrasonic waves. In other words, it causes low reliability of the treatment sequence. Further, in addition to such a problem, there is a problem that cautery unevenness occurs in the treatment of the heart.

On the other hand, in the present embodiment, the focal point 8 is formed to have a diameter of, for example, about 10 mm and a length of about 15 mm, and the focal point 8 is continuously moved at a constant speed along a trajectory covering the affected part. Then, in accordance with the continuous movement of the focal point 8, the therapeutic ultrasonic wave is continuously irradiated. Thereby, the conventional problems, that is, problems such as prolonged treatment time, difficulty in control, and uneven ablation can be solved.

The trajectory on which the focal point 8 moves can be changed according to the shape of the affected part. For example, a spiral shape as shown in FIG. 2A and a concentric circular shape as shown in FIG. , A parallel reciprocating shape as shown in (c), a geometric pattern as drawn by a design ruler as shown in (d) to (g), a random shape as shown in (h), and (i)
Various types such as a line reciprocating shape as shown in Fig. 7 are prepared, and may be selected according to the shape of the affected part and other factors.

In each case, the focal point 8 is continuously moved at a constant speed from the start point to the end point as shown in FIG. In the meantime, it is the same that the therapeutic ultrasonic waves are continuously irradiated with constant energy. However, depending on the type of trajectory used, the trajectory may be dense or rough. In this case, the energy distribution can be made uniform by suppressing the irradiation energy per unit time of the therapeutic ultrasonic wave when the focal point 8 passes through a dense place to be lower than when passing through a rough place. . As a method of suppressing the irradiation energy per unit time, as shown in FIG. 4, the irradiation of the therapeutic ultrasonic wave may be intermittently performed, the gain of the RF amplifier 14 may be temporarily reduced, or The amplitude of the continuous wave generated by the continuous wave generation circuit 11 may be reduced.

Next, as a method of further simplifying the control, the focal point 8 is made to continuously move on a predetermined trajectory, and during the movement, irradiation of therapeutic ultrasonic waves is performed as shown in FIG. By simply controlling the stop and its stop, it is possible to cauterize a very complicated affected part as shown in FIG. 6 without inviting a circular affected part as shown in FIG.

In the above description, the focus 8 is continuously moved by continuously moving the entire applicator 1 to heat the affected part evenly and uniformly. However, as shown in FIG. The eccentric rotation mechanism 23 is incorporated in the frame 12 of the applicator 1, and the focus 8 is moved by moving only the therapeutic ultrasound source 2 while the frame 12 and the ultrasound probe 16 for imaging are fixed to the patient. You may make it do. The eccentric rotation mechanism 23 is configured such that the rotation axis thereof is shifted with respect to the center axis of the therapeutic ultrasonic wave, and moves the therapeutic ultrasonic generation source 2 by a movement like a swing. Only one is required, and simplification of the mechanism and space saving can be achieved. If the same movement as the arm 22 is to be performed, movement of at least three orthogonal axes is required, and a mechanism for the movement is complicated, and the mechanism cannot be easily accommodated in the frame 12 due to a space problem.

In the above description, the movement of the focal point 8 is
Although it followed the movement of the applicator 1 itself,
As shown in FIG. 9, by employing a phased array type therapeutic ultrasonic wave generating source 27 and controlling the phase of a signal for driving each piezo element by a phase control circuit 24,
The focal point 8 may be moved. The present invention is not limited to the embodiments described above, and can be implemented with various modifications.

[0030]

As described above, according to the present invention,
By combining the continuous movement of the focal point and the continuous irradiation of therapeutic ultrasound, the control of the movement and irradiation of the focal point is simplified, the treatment time is significantly reduced, and the ablation unevenness is reduced. it can.

[Brief description of the drawings]

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

FIG. 2 is a schematic diagram illustrating an example of a movement locus of a focal point.

FIG. 3 is a time chart showing focal point movement and irradiation of therapeutic ultrasonic waves according to the embodiment.

FIG. 4 is a time chart for explaining a method of changing irradiation energy per unit time of therapeutic ultrasonic waves between a dense portion and a rough portion of a focal locus according to the embodiment.

FIG. 5 is a schematic view showing another example of the movement of the focal point and the irradiation of the therapeutic ultrasonic wave according to the embodiment.

FIG. 6 is a schematic view showing an application example of FIG. 6;

FIG. 7 is a time chart corresponding to FIG. 5;

FIG. 8 is a modified example of the applicator of FIG. 1;

FIG. 9 is a modified example of the ultrasonic therapy apparatus of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Applicator, 2 ... Therapeutic ultrasonic wave source, 4 ... Coupling liquid, 5 ... Coupling membrane, 8 ... Focus, 9 ... System controller, 10 ... Console panel, 11 ... Continuous wave generation circuit, 12 ... Frame , 14 RF amplifier, 15 impedance matching circuit, 16 ultrasonic probe, 17 ultrasonic diagnostic device, 18 digital scan converter (DSC), 19 CRT, 20 stage controller, 21 stage, 22 arm 23 eccentric rotating mechanism 24 phase control circuit

Claims (6)

[Claims] 1. A therapeutic ultrasonic generating source, a driving unit for driving the therapeutic ultrasonic generating source to generate a therapeutic ultrasonic wave, and a focus moving unit for moving a focal point of the therapeutic ultrasonic wave. Controlling the driving means and the focal point moving means so as to continuously irradiate the therapeutic ultrasonic waves while continuously moving the focal point of the therapeutic ultrasonic waves along a trajectory covering the object to be treated; An ultrasonic treatment apparatus, comprising: 2. A therapeutic ultrasonic generating source, a driving unit for driving the therapeutic ultrasonic generating source to generate a therapeutic ultrasonic wave, and a focus moving unit for moving a focal point of the therapeutic ultrasonic wave. When treating the entire treatment target while moving the focal point of the treatment ultrasonic wave along a trajectory covering the treatment target, the treatment ultrasonic wave is continuously moved while continuously moving the focus. An ultrasonic treatment apparatus comprising: a control unit that controls the driving unit and the focus moving unit so that a section to be irradiated is included in at least a part of the trajectory. 3. A therapeutic ultrasonic wave generating source, a driving unit for driving the therapeutic ultrasonic generating source to generate a therapeutic ultrasonic wave, and a focus moving unit for moving a focal point of the therapeutic ultrasonic wave. While continuously moving the focal point of the therapeutic ultrasonic wave along a predetermined trajectory, continuous irradiation and stop of the therapeutic ultrasonic wave are alternately performed according to the shape of the treatment target or the region including the treatment target. An ultrasonic treatment apparatus comprising a control unit for controlling the driving unit and the focal point moving unit so as to repeat. 4. The control unit according to claim 1, wherein the irradiation energy of the therapeutic ultrasonic wave per unit time is reduced at a place where the trajectory of the focal point is dense, as compared with a place where the trajectory is coarse. The ultrasonic therapy apparatus according to any one of claims 3 to 7. 5. An ultrasound probe for imaging is provided on the same frame on which the ultrasound source for treatment is supported, and the ultrasound source for treatment is provided by the ultrasound probe for imaging. The ultrasonic treatment apparatus according to claim 1, wherein the ultrasonic treatment apparatus is supported by the frame so as to be movable independently of the ultrasonic therapy apparatus. 6. The ultrasonic treatment source according to claim 1, wherein the ultrasonic treatment source is supported so as to be rotatable around a rotation axis deviated from a central axis of the ultrasonic treatment wave.
The ultrasonic treatment apparatus according to any one of claims 3 to 3.