JP3225526B2 - Ultrasound therapy equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic therapy apparatus suitable for treating malignant tumors and calculi.

[0002]

2. Description of the Related Art U.S. Pat. No. 48217 discloses a conventional example in which an ultrasonic aiming and monitoring function is added to a malignant tumor treatment apparatus using ultrasonic irradiation and a calculus breaking treatment apparatus using shock wave irradiation.
An apparatus incorporating a single ultrasonic probe which is relatively small with respect to the transmission aperture of ultrasonic waves or shock waves, such as No. 30, is conventionally known. In such a device, sound waves are used both for generating a therapeutic effect and for aiming and monitoring, so that the device has self-alignment and suppresses aiming errors due to refraction in a living body. There is a principle advantage that can be.

[0003]

Although the above technology has enabled focused acoustic wave treatment with a small aiming error, from the viewpoint of treatment monitoring, the above technology alone cannot be said to be insufficient. That is, in the case of calculus crushing treatment,
It is only possible to determine whether or not the shock wave has hit the calculus by monitoring the movement of the calculus receiving the shock wave by the radiation pressure on the ultrasonic image. In the case of malignant tumor treatment, the difference in acoustic impedance between the tumor and the surrounding tissue is so small that it is difficult to monitor the movement of the treatment site due to radiation pressure on the ultrasonic image. Further, from the viewpoint of preventing side effects on the surrounding tissues, it is important to monitor and suppress cavitation occurring at sites other than the target site of treatment, but it is extremely difficult with only the above technology.

[0004] It is an object of the present invention to solve such a problem and to realize an apparatus capable of accurately monitoring that a therapeutic focused sound wave hits a treatment target site. Another object of the present invention is to enable a focused acoustic wave treatment without causing side effects other than at a treatment target site.

[0005]

In order to solve the above-mentioned problems, according to the present invention, a plurality of groups of ultrasonic transmitting and receiving units each having a scantable directivity are provided to a focused acoustic wave generating and transmitting device for aiming and monitoring. A transducer that is capable of receiving not only the echoes of the pulsed ultrasound transmitted by itself, but also the even harmonic signals of the ultrasound transmitted by the transmitter. The configuration is as follows. Further, a plurality of two-dimensional pulse echo images constituted by ultrasonic signals obtained by transmitting and receiving while scanning each of the plurality of group transducers, and an even harmonic signal of an ultrasonic wave transmitted by the transmitter. Is configured to superimpose and display a plurality of images indicating the azimuth and intensity received by each of the plurality of group transducers.

[0006]

[Action] In many cases, from the area where calculi are crushed or the area where tumor tissue is destroyed due to the collapse of cavitation due to the action of focused sound waves, even harmonics of the focused sound waves are often used. Sound waves are being generated. Attach an ultrasonic transducer that can receive even-numbered harmonics to the focused acoustic wave generating and transmitting device and has directivity that can be scanned, so that imaging by ultrasonic transmitting and receiving not only before and after irradiation of focused acoustic waves but also during irradiation Is performed, the obtained superimposed image is superimposed, and with the reception of the even-numbered harmonics, a band image of a semi-straight line indicating the azimuth as viewed from the ultrasonic transducer in the generation region is obtained.

[0007] With this alone, it is not possible to detect in which portion of the half-line band region an even-numbered harmonic is actually generated. However, by performing ultrasonic imaging from a plurality of different directions on one region, a band-like image of a plurality of semi-straight lines intersecting with each other in the region can be obtained for one even-number harmonic generation region. . From this intersection, a position where even-numbered harmonics are generated, that is, a position where calculus is crushed or cavitation is crushed, is detected and displayed on the ultrasonic echo tomographic image.

[0008]

Embodiments of the present invention will be described below. 1 and 2 are a cross-sectional view of an applicator according to one embodiment of the present invention and a circuit configuration diagram of the entire treatment apparatus, respectively.

A focused strong acoustic wave transmitting portion of the applicator is provided on one side of the light metal substrate 1 which also serves as an acoustic matching material, a ground electrode, and a heat sink, with a resonance frequency of 750 k made of piezoelectric ceramics.
Hz piezoelectric element 2 is bonded. Further, a water bag 3 containing degassed water is attached as an acoustic coupling with the body of the patient to be treated. Light metal substrate 1
In order to make it possible to focus an intense sound wave on an affected area to be treated and scan a focal point (focal point) in the affected area with a minimum necessary number of transducer elements, an inward spherical radius of curvature is provided. Have been.

[0010] The applicator also includes a plurality of ultrasonic transducers 5 in order to enable the aiming of the focused intense sound wave to the affected part to be treated and the monitoring during the irradiation of the intense sound wave by using an ultrasonic image. -1 and 5-2 are attached.
Each ultrasonic transducer is constituted by an array type ultrasonic transducer composed of about 100 piezoelectric elements for ultrasonic imaging by an electronic scanning pulse echo method. A gear 6 is provided above each ultrasonic transducer.
-1 and 6-2.
Gears 8-1 and 8-2 attached to the tips of and 8-2
The structure can be rotated via the. At the time of rotation, the rotary encoders 9-1 and 9-2 are configured to detect the rotation angle of each ultrasonic transducer, and further, in order to enable vertical movement of the ultrasonic transducer set, linear rotation is performed. The motors 10-1 and 10-2 are mounted, and the linear encoder 11 is used to measure the amount of linear movement.
-1 and 11-2 are attached. The rotation and translation of the ultrasonic transducer are controlled by the control circuit 16-1 and the control circuit 16-1, respectively.
16-2. The entire applicator is arm 12
And is attached to a holding mechanism installed outside via the.

The ultrasonic pulse echo images picked up by the ultrasonic wave transmitters / receivers 5-1 and 5-2, the ultrasonic wave transmitting / receiving amplifier 24, the ultrasonic pulse transmission control circuit 25, the received beam scanning and focusing circuit 26 are , Respectively, the image memory 27-1
And 27-2, and are superimposed and displayed on the display screen 30 as two-dimensional tomographic images 31-1 and 31-2, respectively. Further, when the transducers 5-1 and 5-2 are rotated, a three-dimensional image in a conical area determined by the respective directional beam scanning angles can be formed. In the overlapping range of the two conical regions, a doubly overlapping three-dimensional image is obtained.

When performing treatment using this applicator, the doctor moves and fixes the applicator to a position suitable for treatment of the affected part while observing the displayed image. Thereafter, the focal point of the strong sound wave is aimed at the affected part, and the drive signal calculation circuit 21, the element drive signal generation circuit 22, and the drive amplifier 23 test the focused strong sound wave. At this time, in the vicinity of the focal point of the strong sound wave, a harmonic, particularly an even-number harmonic, is generated due to the nonlinear effect. This harmonic signal undergoes the same processing through the same path as the ultrasonic pulse echo signal, and is displayed superimposed on the pulse echo image. That is, the transducer 5
-1 and 5-2, and the ultrasonic transmitting / receiving amplifier 24,
After passing through the receiving beam scanning and focusing circuit 26, they are temporarily recorded in the image memories 27-1 and 27-2, respectively.
Each of the display screens 30-1 and 32-2 is a half-line band image.
And 32-2. The reason why the image is displayed as a semi-straight band image is that the transmission of the focused intense sound wave is performed continuously instead of in a pulse shape. Is undetectable, but with the above configuration, it is detected as the position where two half-line strip images 32-1 and 32-2 intersect and displayed in a two-dimensional tomographic image. A physician who performs treatment using this apparatus confirms that the harmonic generation position coincides with the affected part by the above-described test shot, and then performs the main irradiation of the focused intense sound wave. If the harmonic generation position is deviated from the affected part, the focus position of the focused intense sound wave is electronically corrected using the function of the drive signal calculation circuit 21 and the test shot is performed again. If it is determined that the degree of harmonic generation is too small or too large or inappropriate, adjust the intensity while referring to the intensity of the transmission of the focused strong acoustic wave displayed on the screen 30, and then perform the test shooting again. Perform Such a process allows for a safer treatment.

In this embodiment, the two transducers are placed inside a water bag. This is an effective configuration for simultaneously detecting cavitation occurring inside the water bag, but if the purpose is to exclusively detect cavitation occurring in the body of the patient to be treated, the transducer must be used. It is desirable to adopt a configuration that is placed outside the water bag. Further, in such a case, there is a method in which a water bag which is a source of cavitation is not used at all.

As a method of superimposing and displaying the images obtained by the plurality of ultrasonic transducers 5 so as to be easily viewed, there is a method of making the image signals from the respective ultrasonic transducers correspond to different colors.

[0015]

As described above, according to the present invention, it is possible to realize a treatment apparatus capable of easily confirming, on an image, that focused intense sound waves are correctly focused on an affected part, As a result, safer treatment can be achieved.

[0016]

[Brief description of the drawings]

FIG. 1 is a sectional view of an applicator according to one embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of the entire treatment apparatus according to one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light metal board | substrate, 2 ... Element group for transmitting strong acoustic waves, 3 ...
..Water bag for acoustic coupling, 4... Body of patient to be treated, 5-1..., Ultrasonic transmitting / receiving element group for aiming monitoring, 6
-1 to 2 ··· Ultrasonic transducer rotation gear, 7-1 to 2 ·
··· Rotating motor, 8-1-2 ····· Gear, 9-1–2 ··· Rotary encoder, 10-1–2 ··· Linear motor for moving ultrasonic transducer, 11-1–2 ..Linear encoders,
12 ··· Applicator arm, 16-1-2 ··· Ultrasonic transducer rotation / translation control circuit, 20 ··· Main control circuit, 21 ···
Intensive sound wave transmitter drive signal calculation circuit, 22 ... strong sound wave transmitting element drive signal generation circuit, 23 ... drive amplifier, 24 ... ultrasonic wave transmission / reception amplifier, 25 ... ultrasonic pulse wave transmission Control circuit, 26
... Received beam scanning and focusing circuit, 27-1
2 ... image memory, 28 ... display circuit and display, 30
... Display screen, 31-1 ~ 2 ... 2 by pulse echo method
Dimensional tomographic image, 32-1 to 2... Image displaying the direction of generation of harmonics of strong sound waves.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) A61B 17/22 A61B 18/00-18/28 A61N 7/00

Claims (2)

(57) [Claims] An ultrasonic transmitter for transmitting a focused ultrasonic wave for treatment, transmitting / receiving an ultrasonic wave for an image , and the focused ultrasonic wave
A plurality of ultrasonic transducers for receiving the harmonics of the focused ultrasonic waves, and a half indicating the direction of the generation region of the harmonics as viewed from the ultrasonic transducer, which is obtained by receiving the harmonics of the focused ultrasonic waves. Ultrasound therapy, comprising: a plurality of image memories for storing linear images; and a display circuit for obtaining and displaying intersections of the semi-linear images from the images stored in the plurality of image memories. apparatus. 2. The ultrasonic therapy apparatus according to claim 1, wherein a pulse echo image obtained by said transducer is superimposed on an intersection of said semi-linear image.