JPH02215451A - Calculus crushing device - Google Patents

Abstract

PURPOSE:To exactly irradiate a calculus part with an impulse wave by generating a low pressure ultrasonic wave by using a piezo-element group, and displaying a change of a peak value with time in the prescribed period of a reflected wave together with an image near the calculus part. CONSTITUTION:A pulser 6 is connected to a piezo-element group 2 and out of the reflected waves, which are received by the piezo-element group 2, from the inside of the body of a patient 4, only a signal near the focal point of the piezo-element group 2 is extracted by a reception circuit 12 according to a time gate signal from a sequence controller 8 and inputted to a peak detection circuit 13. Then, a reflected wave peak value in a signal period is detected and inputted to an imaging device 14. The imaging device 14 transmits the ultrasonic wave through an ultrasonic probe 3 for imaging to the inside of the body of the patient 4 and receives the reflected wave and an ultrasonic B mode image is displayed together with a graph showing the change with the passage of time in the reflected peak value. Since a coincident state between a calculus 5 and the focal point can be known, a time, in which the reflected wave peak value is enough large, can be judged as timing to irradiate the calculus with the impulse wave.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a stone crushing device that uses shock waves to crush and treat stones, and particularly relates to a stone crushing device that uses a piezo element as a shock wave source. .

(Prior art) In recent years, as a method for removing kidney stones and other stones without surgery, a method has been proposed in which shock waves are focused from outside the body onto the stone site within the body to crush the stone, and one method has become widely used. It's here. However, although this method is less invasive to the patient than surgery, when the shock wave source is focused away from the stone site and focused on normal tissue, side effects on normal tissue are inevitable. In fact, the stone site often moves away from the focus of the shock wave source due to the patient's respiratory movement or body movement.

In order to solve such problems, in particular, a stone crushing device using a piezo element as a shock wave source was developed in Japanese Patent Application Laid-Open No. 62-49.
As described in Publication No. 843, ultrasonic waves with lower pressure than shock waves are irradiated into the body using a piezo element for stone crushing, and the focus of the shock wave source and the stone site are determined from the intensity of the reflected waves near the focus. There is a known method that determines the matching status of the . According to this method, by irradiating a shock wave only when the focal point and the stone site coincide, it is possible to prevent erroneous irradiation due to respiratory movement or the like.

Furthermore, as described in US Pat. No. 4,771,787, a method has also been considered in which the reflected wave signal is displayed as an A-mode waveform on a display together with an ultrasound image of the vicinity of the stone site. We believe that visualizing the intensity of the reflected waves in this way will provide clues as to how the focal point of the shock wave source matches the stone site (whether they match or not, the extent of the match, etc.), and the degree of fragmentation. It will be done.

However, simply displaying the A-mode waveform is not enough.
It is possible to know only the instantaneous state, and it is not possible to know the temporal changes in the coincidence between the focal point and the stone site due to progress of fragmentation or irreversible movement of the stone due to body movement.

Therefore, it is difficult to find the appropriate shock wave irradiation timing from this display. Furthermore, when performing the positioning operation of the shock wave source, it is necessary to repeat trial and error many times in order to grasp the change in the state of coincidence between the focal point and the calculus site as a result of the operation.

(Problem to be solved by the invention) In this way, low-pressure ultrasound is irradiated into the body along the same route as the shock wave, and the coincidence between the focus of the shock wave source and the stone site is determined from the intensity of the reflected wave from near the focus. With conventional technology that displays the signal of the reflected wave as an A-mode waveform, it is possible to only know momentary conditions such as the coincidence between the focus of the shock wave source and the calculus site, the degree of fragmentation, etc. It is not possible to know the temporal changes in the concordance between the stone and the site of the stone. For this reason, it is difficult to find the appropriate irradiation timing of the shock wave, and even when positioning the shock wave source, it is difficult to grasp changes in the alignment between the focal point and the stone site, so trial and error must be repeated many times. There was a problem that it had to be done.

The present invention provides a stone crushing device that can easily grasp changes over time in the coincidence of the focal point of the shock wave source and the stone site, thereby making it possible to irradiate shock waves accurately, and that allows for easy positioning of the shock wave source. The purpose is to provide

[Structure of the invention]

(Means for Solving the Problems) The present invention provides at least a part of a piezo element group that is a shock wave source, or a second piezo element group that is different from a first piezo element group that is a shock wave source.
A graph that generates low-pressure ultrasound using a group of piezo elements, receives the reflected waves of the low-pressure ultrasound from within the patient's body, detects the peak value within a predetermined period, and shows the change in this peak value over time. is characterized in that it is displayed on the display together with an image of the vicinity of the stone site within the patient's body, such as an ultrasound B-mode image.

Furthermore, the detected peak value is compared with a predetermined threshold value to determine the magnitude relationship, and when the peak value is greater than or equal to the threshold value, a shock wave is generated, and a graph showing the temporal change of the detected peak value and the threshold value is created inside the patient. It is characterized by being displayed on the display together with an image of the vicinity of the stone site.

(Function) The peak value of the reflected wave reflects the coincidence between the focal point of the piezo element group, which is the shock wave source, and the calculus site, and the better the degree of coincidence, the larger it is. By displaying a graph showing the change over time in the reflected wave peak value, it is possible to know the appropriate timing to irradiate the shock wave. This graph is displayed on the same display along with images of the area near the stone site.
Since the correspondence between the correspondence between the focal point and the stone site and the change in the image can be clearly seen, it is also effective in positioning the shock wave source. Furthermore, since the degree of time during which the focal point and the stone site are in a coincident state during the treatment time can be determined, the state of shock wave irradiation during the treatment time can be determined.

Furthermore, when controlling the generation of shock waves based on the magnitude relationship between the reflected wave peak value and the threshold value, it is possible to display not only the temporal change in the reflected wave peak value but also the threshold value as a graph at the same time, which will allow you to see the relationship between the shock wave generation state and the image. This is useful for correcting the position of the shock wave source.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a stone crushing device according to an embodiment of the present invention. In the figure, a therapeutic applicator 1 includes a piezo element group 2 in which a plurality of ring-shaped piezo elements are arranged concentrically and arranged in a spherical shell shape as a whole so that the ultrasonic wave transmitting/receiving surface forms a concave surface, and the piezo elements It consists of an imaging ultrasound probe 3 inserted into the center of group 2. As shown in the figure, this applicator 1 is brought into contact with a patient 4 through a flexible ice bag (not shown) in order to crush and treat a stone 5 inside the patient's body. The imaging ultrasound probe 3 is configured to be movable in the axial direction and directions around the axis.

A pulser (pulse generating means) 6 is connected to the piezo element group 2. Although only one pulser 6 is shown in the figure, in reality, the same number of pulsers as the number of piezo elements are provided. Pulsar 6 is controller 8 connected to console 7
Driven by control from A changeover switch 9 controlled by a controller 8 is connected to the power input terminal of the pulser 6.
A high voltage power supply 10 and a low voltage power supply 11 are selectively connected via the high voltage power supply 10 and the low voltage power supply 11.

The piezo element group 2 is also connected to a receiving circuit 12. The receiving circuit 12 extracts only the signal near the focal point of the piezo element group 2 out of the reflected waves from the body of the patient 4 received by the piezo element group 2, and amplifies and detects the signal using the time gate signal from the sequence controller 8. This receiving circuit 1
The output signal No. 2 is input to the peak value detection circuit 13, and the peak value of the reflected wave within the period of the time gate signal is detected. The output signal of the peak value detection circuit 13 is input to the imaging device 14.

The imaging device 14 transmits ultrasonic waves into the body of the patient 4 via the imaging ultrasonic probe 3 and receives reflected waves to display an ultrasonic B-mode image on a display such as a CRT. Since it is similar to an ultrasonic imaging device used in an ultrasonic diagnostic device or the like, detailed explanation will be omitted. While observing this B-mode image, the operator (such as a doctor) focuses the piezo element group 2 on the stone 5.
Positioning is performed by moving it so that it matches the .

In the present invention, a graph (trend graph) showing the change over time of the reflected wave peak value detected by the peak value detection circuit 13 is displayed on the display of the imaging device 14.
Displayed with the mode image. An example of what is displayed on this display is shown in FIG.

In Figure 2, 21 is the display screen, 22 is B
This is a mode sector image, and a trend graph 23 of reflected wave peak values is displayed in a stepwise manner below the sector image 22 while being scrolled in the time axis direction (horizontal direction in the figure). The right end 24 of the trend graph 23 is the B-mode sector image 2
2 represents the reflected wave peak value corresponding to the current state of the stone 5, and from this value, it is possible to know how the stone 5 and the focal point match in the current state. It is desirable that the display sensitivity and time axis scale of the trend graph 23 be variable, for example, by a volume, a changeover switch, etc. provided on the console 7.

From the display of the trend graph 23, the operator can determine that it is time to irradiate the shock wave when the peak value of the reflected wave becomes sufficiently large.

When the operator inputs a command to generate a shock wave through the console 7, the changeover switch 9 is switched to the high voltage type 1iIX10 side under the control of the controller 8, and the pulser 6 is activated to apply high voltage to the piezo element group 2. By supplying the pulse, a shock wave is generated with the focus of the piezo element group 2 correctly aligned with the site of the calculus 5.

In addition, since the trend graph 23 is displayed on the display together with the B-mode sector image 22 near the stone 5,
The operator can clearly see the correspondence between the focal point and the stone site and the change in the sector image. As a result, the operator can understand from the display which direction the piezo element group 2 should be moved to make the focal point coincide with the site of the calculus 5, so that the positioning operation of the piezo element group 2 can be easily performed.

In addition, if the scale of the time axis is set so that the time width displayed on the trend graph 23 is about the same as the treatment time, for example, about 1 hour, the time during which the focal point and the stone site coincide during the treatment time can be It is possible to know the ratio, that is, data on the state of shock wave irradiation, and to record it.

FIGS. 3 and 4 show other display examples on the display. In FIG. 3, the temporal change in the reflected wave peak value is displayed as a discrete bar graph 25 in the time axis direction. In addition, in FIG. 4, the temporal change in the reflected wave peak value is smoothed and displayed as a smooth graph 26, making it easier to see than in the case of FIG.

FIG. 5 shows another embodiment of the present invention, in which a determination circuit 15 is added to the configuration of FIG.

This determination circuit 15 compares the reflected wave peak value detected by the peak value detection circuit 13 with a predetermined threshold value vth that is preset or input from the outside to determine the magnitude relationship. When the reflected wave peak value is equal to or higher than the threshold value vth, a shock wave generation command signal is sent from the determination circuit 15 to the controller 8, and the changeover switch 9 is switched to the high voltage power supply 10 side under the control of the controller 8, and the pulser 6 is activated. A shock wave is generated by supplying a high voltage pulse to the piezo element group 2.

Further, as a result of the determination by the determination circuit 15, when the reflected wave peak value is less than the threshold value, the controller 8 switches the changeover switch 9 to the low voltage power supply 11 side, and in that state, the pulser 6 is activated. Low-pressure ultrasound is emitted again and the same operation is repeated.

Here, as in the previous embodiment, the imaging device 14 displays the B-mode sector image and the trend graph of the reflected wave peak value, and also displays information on the threshold value vth. FIG. 6 is a display example in this embodiment, in which information on the threshold value vth is displayed as a line 27 together with a trend graph 23.

FIG. 7 is another display example of the embodiment shown in FIG. 5, in which the reflected wave peak value is displayed as a histogram 28, and a portion 29 above the threshold value vth is displayed in a different color tone.

In this way, in this embodiment, when the reflected wave peak value exceeds the threshold value vth, a shock wave is automatically generated, and
By displaying this threshold value vth together with a graph showing changes over time in the reflected wave peak value, the state of shock wave generation that can be inferred from changes in the magnitude relationship between the threshold value vth and the reflected wave peak value, and the image of the stone 5 can be determined. Understand the relationship between Therefore, when it is observed from this display that the number of occurrences of shock waves is small, for example, by correcting the position of the piezo element group 2 while looking at the image of the calculus, it is possible to easily focus on the site of the calculus 5. Can be done.

FIG. 8 shows yet another embodiment of the invention. In the figure, a therapeutic applicator 30 includes a first piezo element group 31 for generating shock waves, in which ring-shaped piezo elements are arranged concentrically and arranged in a spherical shell shape as a whole so that the ultrasonic wave transmitting/receiving surface forms a concave surface. A second piezo element group 32 for generating low-pressure ultrasonic waves, an imaging ultrasonic probe 33 inserted into the center of the piezo element group, and a flexible water bag 35 filled with medium water 34 It is configured. Here, the first and second piezo element groups 31, 32 are arranged alternately in the radial direction, as shown enlarged in FIG. 9, and the total area of each is set larger for the former.

The position controller 36 controls the applicator 30 to the patient.
This is to change the relative position of

This position controller 36 is controlled by a main controller 37 configured using a CPU.

Connected to the main controller 37 is an operation console 38 through which an operator manually issues operation commands.

A high voltage balsa 39 controlled by a main controller 37 is connected to the first piezo element group 31 . Although only one pulser 39 is shown in the figure, in reality, the same number of pulsers as the first piezo element group 31 are provided.

A multiplexer 40 is connected to the second piezo element group 32. The output terminal of a transmitting circuit 41 is connected to the multiplexer 40, and the first low voltage balsa 42 is connected to the input terminal of the transmitting circuit 41. Further, the input end of a receiving circuit 43 is also connected to the multiplexer 40, and the output end of this receiving circuit 43 is connected to a signal analysis circuit 44. Of the reflected wave signals from the patient's body received by the second piezo element group 32 and amplified and detected by the receiving circuit 43, the signal analysis circuit 44 analyzes only the signals near the focal point of the piezo element group, for example, in the previous embodiment. This is a circuit that performs analysis by detecting peak values, etc., similarly to the above, and its output signal is input to the CRT display 45.

On the other hand, the imaging ultrasound probe 33 is equipped with an array transducer at its tip, and each transducer is connected to a multiplexer 46 . The output terminal of a transmitting circuit 47 is connected to the multiplexer 46, and the second low voltage pulser 48 is connected to the input terminal of the transmitting circuit 47. Further, the input terminal of a receiving circuit 490 is also connected to the multiplexer 46, and the output terminal of this receiving circuit 49 is connected to a signal processing circuit 50. The signal processing circuit 50 is, for example, a circuit that performs known signal processing for obtaining a B-mode image and outputs an image signal. The image signal output from the signal processing circuit 50 is stored in the image memory 51 under the control of the main controller 51. The image processing circuit 52 is controlled by the main controller 37, processes the image signals stored in the image memory 51, and sends the processing results back to the image memory 5.
Return to 1. The signal read out from the image memory 51 is C
The image is supplied to the RT display 45 and displayed as a B-mode image.

With such a configuration, in this embodiment as well, the signal analysis circuit 4 is displayed on the CRT display 45 as in the previous embodiment.
4 is displayed together with the B-mode image.

Here, in this embodiment, unlike the previous embodiment, a first piezo element group 31 which is a shock wave source, and a second piezo element group 31 which generates a low pressure ultrasonic wave to obtain a reflected wave from a focal position are used. groups 32 are provided independently, and accordingly, these first and second piezo element groups 31 .
High voltage balsa 3 can also be used as a pulsar for driving 32.
9 and a first low voltage pulser 42 are provided independently. This eliminates the need for the changeover switch 9 in the previous embodiment, which not only reduces the lifespan of the switch 9 and eliminates the generation of noise caused by switching, but also improves the timing of the pulse rate of the high voltage pulses associated with switching. Restrictions on conditions will be relaxed.

That is, the pulse rate of the high voltage pulse can be increased, and the timing difference between the shock wave generated from the first piezo element group 31 and the low pressure ultrasonic wave generated from the second piezo element group 32 can be reduced accordingly. Can be minimized. Therefore, it is possible to irradiate a shock wave after the coincidence of the stone and the focal point is detected by low-pressure ultrasound, but before the stone and the focus shift due to patient's breathing or body movements, reducing the possibility of erroneous irradiation. Further decrease.

10 and 11 show other examples of the therapeutic applicator used in the present invention. In the example of FIG. 10, the first piezo element group 41 and the second piezo element group 42 are arranged in a circle. It is divided in the circumferential direction. In addition, in FIG. 11, a second
A piezo element group 52 is arranged. Even when a therapeutic applicator having these configurations is used, the same effects as in the embodiment shown in FIG. 8 can be obtained.

Note that the present invention is not limited to the above embodiments,
For example, a part of the piezo element group for generating shock waves may be used to generate low pressure ultrasonic waves.

In addition, although the relationship between the resonance frequencies of each piezo element was not mentioned in the embodiment, generally speaking, the higher the resonance frequency, the narrower the ultrasonic pressure distribution at the focal point. The resonant frequencies of the second piezo elements may be made equal or may be adjusted as appropriate. For example, if it is desired to accurately detect the coincidence of a stone and a focus, the resonance frequency of the second piezo element group may be increased, and in some cases higher than that of the first piezo element group. In addition, when the resonant frequencies are the same, the larger the diameter of the piezo element, the narrower the ultrasonic pressure distribution at the focal point. All you have to do is determine.

In addition, the present invention can be implemented with various modifications without departing from the scope.

[Effects of the Invention] According to the present invention, the peak value of the reflected wave of low-pressure ultrasound from within the patient's body within a predetermined period is detected, and a graph showing the change in this peak value over time is plotted near the stone site within the patient's body. By displaying the image on the display, it is possible to know the appropriate timing to irradiate the shock wave, it is easier to position the piezo element group that is the source of the shock wave, and it is also possible to know the irradiation status of the shock wave during the treatment time. can.

In addition, when controlling the generation of shock waves based on the magnitude relationship between the reflected wave peak value and the threshold value, by displaying a graph showing the change in the reflected wave peak value over time and the threshold value, it is possible to understand the relationship between the shock wave generation state and the image. , it becomes possible to easily correct the position of the shock wave source.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a stone crushing device according to an embodiment of the present invention, FIGS. 2 to 4 are diagrams showing examples of displays on the display of the imaging device in the same embodiment, and FIG. A block diagram showing the configuration of a stone crushing device according to another embodiment of the present invention, FIGS. 6 and 7 are diagrams showing examples of display on the display of the imaging device in the same embodiment,
FIG. 8 is a block diagram showing the configuration of a stone crushing device according to yet another embodiment of the present invention, FIG. 9 is a diagram showing the configuration of the first and second piezo element groups in the embodiment of FIG. 8, 1st
0 and 11 are diagrams showing other examples of the ultrasonic applicator used in the present invention. 1.30... therapeutic applicator, 2,31°32.
41, 42.51, 52...Piezo element group 3.33.
...Imaging ultrasound probe, 4...Patient, 5
... Stone, 6 ... Pulsa, 9 ... Selector switch,
10...-high voltage power supply, 11... low voltage power supply, 12.
...Receiving circuit, 13...Peak value detection circuit, 14...
- Imaging device, 15...determination circuit, 21...
Screen, 22...B mode sector image, 23°24.25
, 26.28... Graph showing changes over time in reflected wave peak value, 27... Line 39 showing threshold value... High voltage pulser, 41.47... Transmission circuit 43, . 49...Reception circuit, 44...Signal analysis circuit 45...Display, 42.48...Low voltage pulser. Applicant's representative Patent attorney Takehiko Suzue

Claims (3)

[Claims] (1) an imaging means that acquires an image of the vicinity of a stone site in a patient's body and displays it on a display; a shock wave generating means that uses a first piezo element group to generate a shock wave for crushing the stone; a low-pressure ultrasonic wave generating means for generating an ultrasonic wave having a lower pressure than the shock wave using the second piezo element group; and a receiving means for receiving the reflected wave of the low-pressure ultrasonic wave from within the patient's body; The present invention is characterized by comprising: a peak value detection means for detecting a peak value within a predetermined period of a received reflected wave; and means for displaying a graph showing a change over time in the peak value detected by the means on the display. A stone crushing device. (2) an imaging means that acquires an image of the vicinity of a stone site in a patient's body and displays it on a display; a shock wave generating means that uses a first piezo element group to generate a shock wave for crushing the stone; a low-pressure ultrasonic wave generating means for generating an ultrasonic wave having a lower pressure than the shock wave using the second piezo element group; and a receiving means for receiving the reflected wave of the low-pressure ultrasonic wave from within the patient's body; a peak value detecting means for detecting a peak value of a received reflected wave within a predetermined period; a determining means for comparing the peak value detected by the means with a predetermined threshold value and determining a magnitude relationship; means for activating the shock wave generating means when it is determined that the peak value is greater than or equal to a threshold; and means for displaying a graph on the display showing a temporal change in the peak value detected by the peak value detecting means and the threshold. A stone crushing device characterized by comprising: (3) The stone crushing device according to claim 1 or 2, wherein the first piezo element group and the second piezo element group are provided independently.