JPH0574374B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an ultrasonic hyperthermia device for thermal treatment of cancer.

BACKGROUND ART Recently, hyperthermia devices have been attracting attention as one of the cancer treatment methods, as they have been shown to be more effective when used in combination with other therapies. This conventional hyperthermia device can kill cancer tissue by selectively heating the cancer tissue to 43°C or higher using electromagnetic waves or ultrasound. As a conventional ultrasonic hyperthermia device using ultrasonic waves, for example, a configuration described in Japanese Patent Application Laid-open No. 13956/1983 is known. The conventional ultrasonic hyperthermia device will be described below with reference to the drawings. In FIG. 5, 51 is a B-mode (tomographic image) probe, 52 is a heating probe,
It is contained in a water bag 53. 54 is a position control device that adjusts and controls the positional relationship of both the B-mode probe 51 and the heating probe 52; 55 is a B-mode system connected to the B-mode ultrasonic probe 51; 56 is a clock pulse generator; 57 is a continuous wave generator, and 58 is a burst wave generator, which are connected to the heating probe 52 via a switch 59. 60 is a hot spot detection circuit, 61 is a mixer, 62 is an image processing device, and 63 is a CRT.

Next, the operation of the above conventional example will be explained.

The water bag 53 is brought into contact with the inside of the living body 64, and the B-mode probe 51 is driven by the B-mode system 55 to emit ultrasonic waves toward the living body 64. Living body 6
4 is received by the B-mode probe 51, and this received signal is sent to the B-mode system 55.
The image is sent to the image processing device 62 via the image processor 62, where it undergoes the necessary processing to create an image, and a B-mode image is displayed on the CRT 63. From this B-mode image, cancer tissue 6
5 can be confirmed. On the other hand, the control signal from the clock pulse generator 56 causes the switch 5 to
9, the continuous wave generator 57 and the burst wave generator 58 are switched, and the heating probe 52 is connected to the living body 6.
The ultrasonic output transmitted to the cancer tissue 65 of No. 4 is controlled to heat the cancer tissue 65. Then, the hot spot detection circuit 60 detects a temperature rise in the heated portion of the cancer tissue 65, and the mixer 61 displays the detected temperature on the B-mode image. At this time, the high frequency generation accompanying the nonlinear phenomenon of the living body 64 is maximized where the heating ultrasonic signal is strongest, that is, where the temperature rise is greatest. When a burst wave of ultrasonic waves is emitted from the B-mode probe 52, a hot spot signal 66 is applied to the mixer 61 for mixing at a timing when the high-frequency component detected from the output of the B-mode probe 51 gives maximum amplitude. By using such an ultrasonic hyperthermia device, the heated cancer tissue 65
It is possible to detect the point of maximum temperature rise in the area, that is, the hot spot.

Problems to be Solved by the Invention However, in the configuration of the conventional example as described above, it is unknown what temperature the hot spot point is, and it is difficult to measure the temperature of the heated cancer tissue 65. requires a separate thermometer.
As such a thermometer, an invasive type that is inserted into the living body 64 has been put into practical use. Additionally, a method of measuring the temperature distribution inside the living body 64 using microwave radiometry or ultrasonic CT has been proposed, but this method has not yet been put to practical use.

The present invention solves the problems of the prior art as described above, and makes it possible to perform ultrasonic heating while confirming the area to be heated, and to measure the temperature distribution of the area being ultrasonically heated. , provides an ultrasonic hyperthermia device that can easily heat the heating part to a predetermined temperature, is miniaturized and has improved operability, and also has improved heating efficiency. We provide an ultrasonic hyperthermia device that can improve the temperature of the body, and the heating area can be arbitrarily selected from near the body surface to the depth direction, providing versatility. The object is to provide a sonic hyperthermia device.

Means for Solving the Problems In order to achieve the above object, the present invention provides a B-mode probe for transmitting ultrasonic waves into a living body and obtaining a B-mode image using reflected signals; It is equipped with a heating probe that transmits and heats the inside of the living body, and a means for measuring the acoustic characteristics of the ultrasound inside the living body and obtaining temperature distribution from changes in the acoustic characteristics. The probes for the B mode and the heating probe are arranged concentrically in the center and the outer periphery, and the probes for the B mode and the heating probe are used as temperature measurement probes, and the time is divided into the B mode, heating, and sound measurement probes. When used as a temperature measurement probe, the B-mode probe generates a high-frequency probe wave pulse, and the heating probe generates a low-frequency pump wave pulse.

Additionally, a second heating probe is added.

Preferably, the tomographic imaging probe and the heating probe are arranged at the center and the outer periphery, and the second heating probe is arranged concentrically around the outer periphery of the heating probe.

Effects The present invention has the following effects due to the above configuration.

That is, after obtaining a B-mode image with the B-mode probe and confirming the area to be heated, the area to be heated is heated with the heating probe. Then, the B-mode probe and the heating probe are used as temperature measurement probes to measure the acoustic characteristics of the ultrasound in the living body, and the temperature rise after heating is obtained from the change in the acoustic characteristics. In this way, the operations of B-mode imaging, heating, and temperature measurement are performed in a time-divided manner.

Additionally, a second heating probe is added to the heating operation.

By arranging the probes concentrically, the heating portion can be arbitrarily selected from the vicinity of the body surface in the depth direction.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, a first embodiment of the present invention will be described. FIG. 1 is a configuration diagram showing an ultrasonic hyperthermia device according to a first embodiment of the present invention. In FIG. 1, 1 is a B-mode (tomographic image) probe, 2 is a heating probe,
These B mode probe 1 and heating probe 2
are arranged in an annular array at the center and outer periphery, and are also used as temperature measuring probes, and are enclosed in the water bag 3. 4 is the scanning mechanism of the B mode probe 1 and the heating probe 2; 5 is the B mode scanning mechanism;
A probe wave drive section that drives the mode probe 2; 6 a pump wave drive section that drives the heating probe 2; 7 a phase control section connected to the probe wave drive section 5 and the pump wave drive section 6; As will be described later, the phase relationship of pulse superimposition is controlled when ultrasonic pulses are sent into the living body 21 from the B-mode probe 1 and the warming probe 2. 8 is a receiving section to which the received signal of the B-mode probe 1 is sent, and 9 is an acoustic characteristic measuring section, which performs processing such as frequency analysis from the output of the receiving section 8 and measures acoustic characteristics such as ultrasonic absorption coefficient. . 10 is a temperature measurement signal processing section that extracts temperature information from the acoustic characteristic measurement section 9; 11 is a temperature distribution image display section that displays a temperature distribution image based on the temperature information output from the temperature measurement signal processing section 10. 1
2 is a B-mode signal processing section that processes the output of the receiving section 8, and 13 is a B-mode image display section that displays a B-mode image based on processing by the B-mode signal processing section 12. 14 is a heating control section, and 15 is an overall control section, which controls the scanning mechanism 4, the phase control section 7, the acoustic characteristic measurement section 9, the tomographic image display section 13, and the heating control section 14.

The operation of the above configuration will be described below.

First, the B-mode probe 1 is driven by the probe wave driving unit 5, and, for example, an ultrasonic pulse with a center frequency of 3 MHz is transmitted into the living body 21, and a reflected wave from inside the living body 21 is received, and Scanning mechanism 4
Scanning of the tomographic probe 1 is performed using the following methods. Then, the received signal is guided from the receiving section 8 to the B-mode signal processing section 12 and subjected to signal processing, thereby displaying a B-mode image on the B-mode image display section 13. In the B-mode image, for example, the acoustic characteristics of the cancer tissue 22 within the living body 21 are different from the surrounding area and are displayed brightly, making it easy to confirm the part of the cancer tissue 22 that should be heated. can.

Next, the B-mode probe 1 and the heating probe 2, which are temperature measurement probes, are driven to determine the acoustic characteristics of the temperature measurement site before heating. For example, the heating probe 2 is driven by the pump wave drive unit 6.
An ultrasonic pulse having a center frequency of 0.3 MHz is generated, and the ultrasonic pulses emitted from the B-mode probe 1 are superimposed in a phase relationship as shown in FIG. Then, the phase control section 7 performs phase control. In this case, the living body 21
Inside, the ultrasonic pulse from the strong low-frequency warming probe wave becomes a pump wave pulse, and the high-frequency tomographic image pulse is modulated by the frequency-dependent ultrasonic attenuation and nonlinear effect of the living body 21. This degree of modulation reflects the frequency-dependent ultrasonic attenuation characteristics and nonlinear coefficients, and is affected differently depending on the phase relationships in FIGS. 2a and 2b. By subjecting this modulated tomographic image pulse to signal processing such as frequency analysis in the acoustic characteristic measuring section 9, it is possible to measure the distribution of acoustic characteristics in the propagation direction of the ultrasound waves. The inventors have also discovered that by using this method of superimposing pulses, it is possible to remove the complex scattering characteristics of the living body 21 and obtain ultrasonic absorption coefficients with high precision, and furthermore, it is possible to obtain nonlinear coefficients. This has been revealed through research. Therefore, by scanning the B-mode probe 1 and the heating probe 2, which are temperature measuring probes, with the scanning mechanism 4,
It is also possible to obtain a distribution image of acoustic characteristics similar to the B-mode image, and these measured values are temporarily stored in the temperature measurement signal processing section 10.

Next, the heating operation begins; in this case, the pump wave drive unit 6 performs continuous oscillation in response to a control signal from the heating control unit 14, and a strong continuous wave ultrasonic wave is transmitted from the heating probe 2 into the living body 21. irradiate. In the living body 21, the ultrasound waves progress while being absorbed by the living tissue, so when the heating probe 2 is operated for heating, the ultrasound waves are applied to the predetermined cancer tissue 2 confirmed in advance using a B-mode image.
If the focal length is adjusted to 2, the cancer tissue 22 will be selectively heated. In this case, the B-mode probe 1 may be left inactive, but by scanning the scanning mechanism 4 a little to obtain a tomographic image, it is possible to confirm changes in the tomographic image of the heated area. Furthermore, changes over time in the direction in which the heating ultrasonic waves are irradiated may be recorded as a well-known M-mode image. Alternatively, the frequency of the received signal may be analyzed, changes in acoustic characteristics may be recorded, and rough temperature information may be obtained. Furthermore, the B-mode probe 1 can also be used for heating.

Next, after heating for a predetermined period of time, the temperature measurement probes 1 and 2 for temperature measurement were again operated as described above to measure the temperature at the same location as the acoustic characteristics obtained before heating. Measure the acoustic characteristics after heating. Input this measured value to the temperature measurement signal processing section 10,
Find the difference from the accumulated acoustic characteristics before heating. This temperature measurement signal processing unit 11 has a biological body 2 in advance.
Prepare a database with information such as the temperature dependence coefficient of the acoustic properties of No. 1, for example, the temperature dependence of the ultrasonic absorption coefficient in the liver, approximately 2%/℃, and the speed of sound, 0.2%/℃, and refer to this database. As a result, a two-dimensional distribution image of the temperature increase due to heating can be obtained, and this two-dimensional distribution image is displayed on the temperature distribution display section 11. In this case, the B-mode image display section 13 and the temperature distribution display section 11 are connected to the same CRT.
By doing so, it is possible to display the temperature distribution image in color on the B-mode image obtained in advance, or to display the B-mode image and the temperature distribution image side by side, making it easier to confirm the heating status. Become. If the heating is not sufficient, the above heating operation and temperature measurement operation are repeated again to achieve a predetermined heating state.

In the above embodiment, the B-mode probe 1 and the heating probe 2 are used in combination as the temperature measurement probe, and the two probes have significantly different frequencies.
Although we have described the case where the temperature is measured by superimposing different types of ultrasonic pulses, ultrasonic pulses of one frequency are sent to the living body 21 using either the B-mode probe 1 or the warming probe 2, For example, it is also possible to obtain temperature information by obtaining a frequency-dependent attenuation coefficient and measuring the amount of temperature change.
In this case, the heating probe 2 and the B-mode probe 1 are set to the same frequency, and the large-area portion at the outer periphery in the annular array arrangement is used for heating, and the small-area portion at the center is used for B-mode. , this B-mode probe 1 can also be used as a temperature measurement probe.

With this configuration, it is possible to easily confirm the location to be heated, measure the temperature rise due to heating, and control the heating state while viewing the temperature distribution image. , it is possible to reduce the size of the device.

Next, a second embodiment of the present invention will be described.
FIG. 3 is a block diagram showing a second embodiment of the present invention.

In this embodiment, the same parts as in the first embodiment are given the same reference numerals, and the explanation thereof will be omitted, and the different configuration will be explained. In FIG. 3, 16 is a second heating probe, 17 is a heating drive unit that is controlled by the heating control unit 14 and drives the second heating probe 16, and 18 is a control unit 15.
This is a second scanning mechanism that is controlled by and scans the second heating probe 16.

The operation of the above configuration will be described below.

The operation of obtaining a B-mode image and the operation of obtaining acoustic characteristics before and after heating and measuring temperature are described in Section 1 above.
Since this embodiment is the same as that in the embodiment, only the acceleration operation will be explained. The second scanning mechanism 18 is used to scan the second heating probe 16 on the cancer tissue 22, which is the heating site confirmed in the B-mode image. Next, the heating control section 14 operates in response to a signal from the general control section 15 selecting the heating operation, and similarly to the first embodiment, the pump driving section 6 is operated in a continuous wave mode to perform the first heating operation. The heating probe 2 irradiates the living body 21 with continuous wave ultrasonic waves, and the heating drive unit 17 is made to move in continuous waves to irradiate the living body 21 with powerful ultrasound waves from the second warming probe 16 . As the second heating probe 16, one with the same ultrasonic frequency as the first heating probe 2 may be used, or one with a different frequency of, for example, 0.5 to 1 MHz may be used. These frequencies are desirably selected appropriately depending on the position of the cancer tissue 22 to be heated in the depth direction from the surface of the living body 21.

Note that it is also possible to use a plurality of second heating probes 16, and when using this second heating probe 16, heating can be performed using a B-mode image as in the first embodiment. It is possible to check the area to be heated, measure the temperature rise while heating, and further improve the heating efficiency.

Next, a third embodiment of the present invention will be described.
4a and 4b show an ultrasonic hyperthermia device according to a third embodiment of the present invention, in which figure a is a cross-sectional view of the main part, and figure b is a bottom view of the main part.

In this embodiment, as shown in FIGS. 4a and 4b, temperature measurement is carried out in an annular array consisting of a second heating probe 16, a tomographic imaging probe 1, and a heating probe 2 on the outer periphery. By arranging the probe in a circular pattern around the outer circumference of the probe, the heating area can be arbitrarily selected from near the body surface to the depth direction.
This allows for more efficient heating. In this case, the second heating probe 16
may be the same frequency as the first heating probe 2 or a different frequency. The other configurations are the same as those of the first embodiment.

Effects of the Invention As described above, according to the present invention, after a B-mode image is obtained with a B-mode probe and a region to be heated is confirmed, the region to be heated is heated with a heating probe. Then, the B-mode probe and the heating probe are used as temperature measurement probes to measure the acoustic characteristics of the ultrasound inside the living body, and the temperature rise after heating is obtained from the change in the acoustic characteristics. The heating portion can be easily heated to a predetermined temperature. Furthermore, since the B-mode imaging, heating, and temperature measurement operations are performed in a time-divided manner as described above, the number of probes can be reduced, the overall size of the apparatus can be reduced, and the operability can be improved.

Furthermore, by using the second heating probe, the efficiency of heating can be improved.

By arranging the probes concentrically, the heating site can be arbitrarily selected from near the body surface to the depth direction, providing versatility.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an ultrasonic hyperthermia device in the first embodiment of the present invention, Fig. 2a,
b is a diagram showing the phase relationship of ultrasonic pulses for measuring temperature in the first embodiment, FIG. 3 is a block diagram showing the ultrasonic hyperthermia device in the second embodiment of the present invention, and FIG. a and b show an ultrasonic hyperthermia device according to a third embodiment of the present invention, in which figure a is a sectional view, figure b is a bottom view,
FIG. 5 is a configuration diagram showing a conventional ultrasonic hyperthermia device. DESCRIPTION OF SYMBOLS 1... B mode probe, 2... Heating probe, 5... Probe wave drive unit, 6... Pump wave drive unit, 7... Phase control unit, 8... Receiving unit, 9...
...Acoustic characteristic measurement section, 10...Temperature measurement signal processing section, 1
1...Temperature distribution image display section, 12...B mode signal processing section, 13...B mode image display section, 14...Heating control section, 15...Overall control section, 16...Second heating Probe for use, 17... Drive unit for heating, 21...
...Biological body.

Claims (1)

[Claims] 1. A B-mode probe for transmitting ultrasonic waves into a living body and obtaining a B-mode image using reflected signals;
The B mode is equipped with a heating probe that transmits ultrasonic waves into the living body to heat the inside of the living body, and a means for measuring the acoustic characteristics of the ultrasound inside the living body and obtaining temperature distribution from changes in the acoustic characteristics. The heating probe and the heating probe are arranged concentrically in the center and the outer periphery.
The mode probe and the heating probe are used as temperature measurement probes, and are used time-divided for B mode, heating, and temperature measurement, and when used as a temperature measurement probe, the B mode probe is An ultrasonic hyperthermia device characterized in that a high-frequency probe wave pulse is generated, and a heating probe generates a low-frequency pump wave pulse. 2. The ultrasonic hyperthermia device according to claim 1, further comprising a second heating probe. 3. The ultrasonic hyperthermia device according to claim 2, wherein the second heating probe is arranged concentrically around the outer periphery of the heating probe.