JPH0435656A - Calculus crushing device - Google Patents

Abstract

PURPOSE:To inform whether the delivery rate of shock waves from a shock wave source to a calculus is secured sufficiently or not, and to crush stably, by carrying out the reporting operation when the intensity of reflection waves from the body surface or from an obstacle in the body is at a set value or higher. CONSTITUTION:By connecting a high voltage power source 24 to a pulser 21 to apply a high voltage pulse to a plate coil 51, a strong magnetic flux is generated instantly by the coil 51. Since the magnetic flux penetrates a conductive plate 53, a current is generated in the conductive plate 53 in the direction to erase the magnetic flux. As a result, a strong repelling power is generated between the coil 51 and the conductive plate 53, and strong plane waves (pressure waves) are radiated in the water contacting to the conductive plate 53. The pressure waves are radiated concentrating to a calculus 18 in the body of a patient 17 positioned to the focus position of a sound lens 59 through the sound lens 59 and a coupling device 12. The reflection waves are received by a peizoelectric film 55, and detected as an RF signal, and after that, input to a reflection wave intensity detecting circuit through an amplifier and a detector circuit 26, the intensity (the integrated value or the maximum value) of the reflection wave signals from the body surface or from an obstacle in the body of the patient 17 is detected, and depending on the compared and decided result between the intensity value and the set value, a reporting operation is carried out.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention relates to a stone fragmentation treatment for stone fragmentation by focusing shock waves from outside the patient's body to the stone inside the patient's body using a piezo element or other shock wave source. The present invention relates to a stone crushing device, and particularly to a stone crushing device that irradiates shock waves through a liquid-filled coupling device.

(Prior Art) In recent years, a method of non-invasively crushing stones from outside the body using shock waves has been widely used mainly in the treatment of kidney stones.

As shock wave sources, underwater discharge, electromagnetic induction, micro-explosion, methods using piezo elements, etc. are known.

Such a lithotripter requires good coupling between the shock wave source and the patient's body. The following three methods have been devised as this coupling method.

a. Method of placing the shock wave source and the patient's whole body in the same water tank. S. Method of immersing the part of the patient's body close to the treatment area (in the case of kidney stone treatment, the lower back) in a small water tank containing the shock wave source. A method in which an ice bag-shaped applicator integrated with a coupling device (ice bag) containing water is brought into contact with the patient via a coupling agent such as jelly (hereinafter referred to as the applicator method). Although this method is the most reliable in terms of coupling, it requires the patient's entire body to be wet, which poses a heavy burden on the patient. Also, b
Although this has the advantage of reducing the area to be wetted compared to a, it is difficult to efficiently irradiate the stone site with shock waves because there are restrictions on the contact direction of the shock wave source. The applicator method of C does not wet the patient and has the advantage of being able to direct the shock wave source to the stone site at any angle, so it has been increasingly used recently.

However, with this applicator method, if sufficient contact area between the coupling device and the patient's body surface is not secured,
Most of the shock waves are reflected off the body surface and do not reach the stone, making it impossible to fragment it effectively. Even if one attempts to visually check the state of contact between the coupling device and the patient's body surface, it is difficult to accurately determine whether the contact is good or not.

Additionally, depending on the contact direction of the applicator, the shock waves that should be irradiated to the stone may be reflected by obstacles such as bones in front of the stone and may not be able to reach the stone.
Conventionally, even if such a situation occurs, it would be impossible to know.

(Problems to be Solved by the Invention) As described above, in an applicator-type lithotripter that integrates a shock wave source and a coupling device filled with a liquid that propagates shock waves, conventionally, contact between the coupling device and the patient has been limited. Since there is no means to accurately grasp the situation, there is a problem in that it is difficult to properly grasp the contact situation and perform efficient crushing treatment.

A first object of the present invention is to provide a stone crushing device that can accurately grasp and notify an operator of the contact situation between a coupling device and a patient.

A second object of the present invention is to provide a stone crushing device that is capable of correctly grasping the contact situation between the coupling device and the patient, and controlling the contact situation to improve the contact situation based on this information. There is a particular thing.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the first object, the present invention uses a low pressure wave having a lower pressure than a shock wave through a coupling device for coupling a shock wave source and a patient. The reflected waves are transmitted into the body and the reflected waves are received, and among the received reflected waves, the intensity of the reflected waves from a predetermined area in front of the focus area of the shock wave is detected, and the intensity of the reflected waves exceeds a set value. By performing a notification operation at this time, the operator is notified of the suitability of the contact situation between the coupling device and the patient.

In addition, in order to achieve the second object, the present invention detects the intensity of the reflected wave from near the patient's body surface among the received reflected waves, and when the intensity of the reflected wave is equal to or higher than a set value, the coupling device By replenishing liquid to the coupling device, the contact between the coupling device and the patient is improved.

(Function) When transmitting a low pressure wave, the patient's body surface is the first reflector that the low pressure wave encounters after it begins to propagate. This reflected wave from the body surface can be identified as a product by, for example, detecting the first peak of the reflected wave. If the contact situation between the coupling device and the patient's body surface is sufficiently good in terms of contact area, the intensity of the reflected wave at this body surface will not be very large.

On the other hand, if there is not enough liquid in the coupling device, or if there is not enough coupling agent between the coupling device and the body surface, air may be present in the propagation path of the low pressure wave. Because of the incoming layers, large reflections will occur. Therefore, the intensity of this reflected wave is compared with a preset value, and if the intensity of the reflected wave is greater than or equal to the preset value, it is determined that the contact between the coupling device and the patient's body surface is insufficient, and the operator Notify the parties to that effect. This eliminates the need to irradiate shock waves that do not enter the patient's body and do not contribute to fracture, thereby ensuring reliable treatment. Furthermore, when the intensity of reflected waves from the body surface is high, liquid is automatically replenished into the coupling device, thereby improving contact between the coupling device and the patient.

In addition, if there is an obstacle in front of the stone in the patient's body, the reflected waves from that area will become larger, so by detecting the intensity of the reflected waves, it can be determined whether there is an obstacle or not, and the operator can receive a shock wave. It can prompt you to correct the direction of the source.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a stone crushing device according to an embodiment of the present invention, and shows an example in which a piezo element is used as a shock wave source.

In FIG. 1, the applicator consists of a piezo element 11 that is a source of shock waves, and a coupling device 12 that couples this piezo element 11 to a patient 17. The piezo element 11 has a spherical shell shape as a whole, for example, by arranging ring-shaped unit piezo elements concentrically.

The coupling device 12 is composed of an expandable bag-shaped container consisting of a bellows 13 provided to cover the front of the piezo element 11 and a body surface contact membrane 14. It is filled with water 15.

The body surface contact membrane 14 is made of, for example, a rubber membrane, and is brought into contact with the body surface of the patient 17 on the bed 16 through a coupling agent (not shown) such as jelly during treatment. The shock wave generated from the piezo element 11 is transmitted to the coupling device 1
2 through the water 15 and the body surface contact membrane 14, the patient 1
Focused irradiation is applied to the stone 18 in the body of No. 7.

The coupling device 12 is also connected to a water tank 20 via a pump 19.

Piezo element 11 is connected to balsa 21. Balsa 21 is selectively connected to low voltage power supply 23 and high voltage power supply 24 by switch 22 to generate low voltage pulses or high voltage pulses. The piezo element 11 emits weak ultrasonic waves (low pressure waves) when a low voltage pulse is applied from the balsa 21.
It generates a shock wave when a high voltage pulse is applied.

The piezo element 11 also receives a reflected wave from within the body of the patient 17, converts the reflected wave into an RF signal, and outputs the signal. Amplifier 2
5 amplifies this RF signal, and the detection circuit 26 is an amplifier 25.
Detects the output of and converts it into a single polarity signal. The A/D converter 27, digital memory 28, and digital integration circuit 29 constitute a reflected wave intensity detection circuit 30, and the detection circuit 26
Detect the intensity of the reflected wave from the output.

The controller 31 controls the pump 19, balsa 21, and switch 2 based on commands input via the keyboard 32.
2. Controls the reflected wave intensity detection circuit 30, compares and determines the reflected wave intensity with a set value, which will be described later, and supplies signals to the CRT display 33 and the notification device 34. That is, the controller 31 supplies an on/off signal to the pump 19, supplies trigger pulses at regular intervals to the pulser 21, supplies a switching signal to the switch 22, and supplies the reflected wave intensity detection circuit 30. It supplies a sampling clock to the A/D converter 27, controls writing and reading of the memory 28, controls the digital integration circuit 29, and takes in the integral value.

Next, the operation of this embodiment will be explained with reference to the time chart shown in FIG. At the start of treatment, the switch 22 is controlled by the controller 31 and initially connects the low voltage power supply 23 to the pulser 21. Therefore, when the pulser 21 is activated by a trigger pulse from the controller 31, it first generates a low voltage pulse. As a result, the piezo element 11 generates ultrasonic waves (low pressure waves) that are too weak to become shock waves, and are irradiated into the body of the patient 17 via the coupling device 12 . Ultrasonic waves irradiated into the body are reflected at parts with different acoustic impedances. This reflected wave is received by the same piezo element 11 used for transmission, and RF
It is detected as a doubled signal. The signal is amplified by the RF multiplier signal amplifier 25 and detected by the detection circuit 26.

FIG. 2(a) shows the waveform of the reflected wave signal detected by the detection circuit 26. Here, to is the time when the ultrasound was emitted, and 101 is a reflected wave signal from the body surface of the patient 3. Since there is only the water 15 in the coupling device 12 and the body surface contact membrane 14 from the piezo element 11 to the body surface of the patient 17, it is time t. There is virtually no reflected wave signal between the body surface reflection signal 101 and the body surface reflection signal 101. In the reflected wave intensity detection circuit 30, this detected reflected wave signal is sent to the controller 3.
The digital data is converted into digital data by the A/D converter 27 under the control from 1, and then stored in the memory 28. controller 3
1, from the reflected wave data stored in the memory 28, the second
t in figure (a). Time T from to body surface reflected wave signal 101
By detecting the body surface reflected wave reception start time t1
Detect. This is achieved by the well-known technique of first peak detection.

Next, the controller 31 sets the body surface reflected wave gate 103 in a period τ1 before and after time t1, as shown in FIG. It is called from the memory 28 and transferred to the digital integration circuit 29. The digital integration circuit 29 performs waveform integration of this body surface reflected wave data, calculates the integral value (reflected wave intensity), and supplies it to the controller 31 .

The controller 31 compares the integrated value of the body surface reflected wave data obtained by the digital integration circuit 29 with a first setting value (TH,) input from the keyboard 32. Here, if the integral value is smaller than the set value TH, nothing is done, but if the integral value is greater than the set value TH, patient 1
7 and the coupling device 12 is determined to be insufficient, the notification device 34 using a buzzer or a lamp or both performs a notification operation to alert the operator to that effect. This may cause the operator to determine whether the amount of water 15 in the coupling device 12 is insufficient or if the amount of water 15 in the coupling device 12 is insufficient.
It can be seen that the amount of coupling agent between 2 and the body surface is not sufficient.

In addition, in this embodiment, the controller 31 controls, when the integral value obtained by the digital integration circuit 29 is equal to or greater than the set value TH,
A drive command is sent to the pump 19 to supply water in the water tank 20 to the coupling device 12 to increase the amount of water. This increases the pressure within the coupling device 12, and the body surface contact membrane 14 of the coupling device 12 comes into more reliable contact with the body surface of the patient 17.

Note that the same effect can be expected even if the coupling device 12 is controlled to be replenished with a coupling agent instead of being replenished with water. Of course, instead of these automatic controls, the operator may manually replenish water and coupling agent via the keyboard 32 or the like in accordance with the notification operation of the notification device 34, and furthermore, it is possible to select between automatic and manual operation. You can do it like this.

After such control, the controller 31 operates as shown in FIG. 2(b).
As shown in FIG. 2A, the focal region reflected wave gate 104 for a period τ2 that includes the reflected wave signal 102 from the focal region of the piezo element 11 in FIG. 2(a) is set, and the reflected wave data within this period τ2 is set. (focal area reflected wave data) is read from the memory 28 and transferred to the digital integration circuit 29. Note that since the focal position of the piezo element 11 is known in advance from the shape of the piezo element 11, the focal region reflected wave gate 104 can be set if the weak ultrasonic wave emission time to is known. The digital integration circuit 29 performs waveform integration of the focal region reflected wave data as before, calculates the integrated value, and supplies the integrated value to the controller 31.

The controller 31 thus connects the digital integration circuit 29
The integral value of the focal region reflected wave data obtained in step 1 is compared with a second set value (referred to as TH2) input from the keyboard 32. Here, if the integral value is greater than or equal to the set value TH2, the controller 31 determines that the focus of the piezo element 11 and the stone match, and switches the switch 22 to connect the high voltage power supply 24 to the pulser 21. .

Therefore, when the pulser 21 receives a trigger pulse from the controller 31, it generates a high voltage pulse. As a result, a powerful shock wave is emitted from the piezo element 11,
Irradiation is directed towards the stone 18. However, if it is determined that the contact between the body surfaces is insufficient, the shock wave will not be emitted.

In the above description, the coupling device 1 to the body surface of the patient 17 is
However, as shown in Fig. 3, there are obstacles in the body other than the body surface that obstruct the propagation of shock waves to the stone 18, such as ribs 41, lungs 42, and even intestinal gas (not shown). ) etc. It is important to select an incident path so as to avoid reflection of shock waves from these obstacles as much as possible in order to increase crushing efficiency and to reduce side effects. Therefore, a method for detecting the presence of these obstacles will be explained with reference to the time chart shown in FIG.

The operations from transmitting and receiving weak ultrasonic waves using the piezo element 11 to detecting reflected wave signals are the same as described above. Fourth
Figure (a) is the waveform of the reflected wave signal after detection when there is an obstacle in the shock wave propagation path inside the body, and as in Figure 2 (a), t is the emission time of the weak ultrasonic wave, and 102 is the focal point. A region reflected wave signal, and 105 a reflected wave signal from the body surface and an obstacle in the body existing between the body surface and the focal region (hereinafter referred to as
This is called the body surface/internal obstacle reflected wave signal). here,
If the shock wave propagation path includes ribs 41 and lungs 4 as shown in Figure 3,
If there are obstacles such as 2, they act as strong reflectors for shock waves and ultrasonic waves, so a large reflected wave is detected by the piezo element 11, and the obstacles on the body surface and inside the body shown in Fig. 4(a) are detected. The level of the reflected wave signal 105 increases.

In the reflected wave intensity detection circuit 30, the reflected wave signal from the detection circuit 26 is digitized by the A/D converter 27, and the reflected wave data is stored in the memory 28, as before. The controller 31 controls the ultrasonic emission time 1. Detect a reception start time t1 of the body surface reflected wave after a time T from , and then after time t1,
As shown in FIG. 4(b), a body surface/internal obstacle reflected wave gate 106 with a time width τ3 is set, and the reflected wave data (external/internal obstacle reflected wave data) within this gate period τ3 is stored in the memory 28. This is called from the digital integration circuit 29.
Transfer to. In the digital integration circuit 29, this extracorporeal
The internal obstacle reflected wave data is waveform integrated to calculate the integral value (reflected wave intensity) and supply it to the controller 3.

Next, the controller 31 compares the integrated value of the body surface/external obstacle reflected wave data obtained by the digital integration circuit 29 with a third setting value (TH,) input from the keyboard 32. .

Here, if the integral value is smaller than the set value TH, nothing will be done, but if the integral value is greater than the set value TH, it is determined that there is a large obstacle in the propagation path of the shock wave, and the buzzer is activated. The operator is notified of this using a notification device 34 such as a lamp or a lamp, or a CRT display 33.The operator who receives the alert uses an applicator, that is, a piezoelectric device, to prevent obstacles from entering the shock wave propagation path. The position and orientation of the element 11 and the coupling device 12 are adjusted.In addition, if there is a mechanism for moving the position of the applicator, information is fed back to it from the controller 31 so that there are fewer obstacles in the incident path of the shock wave. It is also possible to automatically adjust the position so that the

In the above embodiment, in order to detect the intensity of reflected waves from each region such as the body surface, focal region, and internal obstacles, time gates (103, 10
4,106) and integrated the reflected wave signal within the gate period, but the maximum value of the reflected wave signal within the time gate period may also be detected. In addition, when using the integration method, instead of simply integrating, in order to take into account the influence of the sound field from the piezo element to the focal region, the reflected wave signal is multiplied by a weighting function according to the depth direction and then integrated. is also valid.

Further, in the embodiment, the applicator is provided below the patient, but it goes without saying that it may be provided above the patient.

Furthermore, although a piezo element was used as the shock wave source in the above embodiment, the present invention is also effective when using other shock wave sources.

FIG. 5 is a diagram showing an embodiment using an electromagnetic induction type shock wave source. The electromagnetic induction shock wave source includes a coil 51 wound into a flat plate, an insulating sheet 52, a conductive plate 53, and an insulating sheet 5.
4 are arranged in parallel with each other very close to each other, and are integrally constructed, and the flat coil 51 is fixed. The coil 51 is connected to a pulser (not shown), and the pulser is selectively connected to a low-voltage power source or a high-voltage power source via a switch as in FIG. 1.

A piezoelectric film 55 is placed in front of this electromagnetic induction type shock wave source. This piezoelectric film 55 has a piezoelectric layer 56
Electrodes 57 and 58 are formed on both sides of the electrode 5.
7.58 is connected to an amplifier (not shown), and the output of the amplifier is connected to a reflected wave intensity detection circuit via a detection circuit as in FIG. Acoustic lens 5 is placed in front of piezoelectric film 55.
9 is arranged, and a coupling device 12 similar to that shown in FIG. 1 is provided on the front surface thereof.

Note that water is also filled between the shock wave source and the acoustic lens.

When a high voltage power source is connected to the pulser and a high voltage pulse is applied to the flat coil 51, a strong magnetic flux is instantaneously generated by the coil 51. Since this magnetic flux also penetrates the conductive plate 53, a current is generated within the conductive plate 51 in a direction that attempts to cancel this magnetic flux, causing the coil 51 and the conductive plate
A strong repulsive force is generated between the conductive plate 53 and the conductive plate 53, and a strong plane wave (pressure wave) is radiated into the water in contact with the conductive plate 53. This pressure wave is positioned at the focal point of the acoustic lens 69, and the patient 17
The concretion 18 in the body of the patient is irradiated with focused radiation via the acoustic lens 69 and the coupling device 12. At this time, a nonlinear phenomenon occurs while the pressure wave propagates through the water, and the pressure wave turns into a shock wave at the focal point, making fracturing treatment possible.

On the other hand, before such treatment, a low pressure wave is generated by connecting a low voltage power source to the pulser and applying a low voltage pulse to the flat coil 51, and is transmitted through the acoustic lens 59 and the coupling device 12. Irradiation is applied into the body of the patient 17. Ultrasonic waves irradiated into the body are reflected at parts with different acoustic impedances. This reflected wave is reflected by the piezoelectric film 55.
After being detected as an RF multiplied signal, it is input to a reflected wave intensity detection circuit via an amplifier and a detection circuit.

Hereinafter, as in the previous embodiment, the reflected wave intensity detection circuit detects the intensity (integral value or maximum value) of the reflected wave signal from the body surface or internal obstruction of the patient 17, and compares and determines the intensity with the set value. Notification operations are performed according to the results.

FIG. 6 is a diagram showing an embodiment using an underwater discharge type shock wave source. The underwater discharge type shock wave source has two focal points F, , F2
a spheroidal reflecting mirror 61 having a first
It is mainly composed of a discharge gap 62 located at the focal point F1. The discharge gap 62 is driven by a discharge circuit (not shown) to cause discharge, and at that time generates a shock wave. This shock wave is irradiated to the stone 18 in the body of the patient 17, which is positioned at the second focal point F2 of the reflecting mirror 61, and a crushing treatment is performed.

In this embodiment, a piezoelectric sensor 63 is located near the first focal point F1, for example, just before the discharge gap 62 as shown in the figure.
is located. This piezoelectric sensor 63 is connected to an amplifier (not shown), and the output of the amplifier is connected to a reflected wave intensity detection circuit via a detection circuit as in FIG. 1.

In this embodiment as well, before treatment, the discharge circuit is operated at a low voltage to generate a weak pressure wave from the discharge gap 62, and after the reflected wave is detected by the piezoelectric sensor 63, it is reflected via the amplifier and the detection circuit. The signal is input to the wave intensity detection circuit, and as in the previous embodiments, the intensity of the reflected wave signal from the body surface and internal obstacles of the patient 17 is detected, and a notification operation is performed according to the result of comparing these signals with the set value. All you have to do is

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

[Effects of the Invention] According to the present invention, among the reflected waves of the low pressure waves irradiated into the patient's body along the shock wave path via the coupling device, the area in front of the convergence area of the shock waves, that is, the body surface and By performing a notification operation when the intensity of the reflected wave from an internal obstacle exceeds a set value, the operator can be informed of the appropriateness of the contact situation between the coupling device and the patient, that is, the propagation path of the shock wave from the source of the shock wave to the stone. It is possible to tell whether or not the amount of water is sufficiently secured, and a stable crushing effect can be obtained.

In addition, by prompting the operator to change the position and orientation of the applicator to avoid obstacles that reflect shock waves inside the body and irradiate shock waves, side effects caused by shock waves being irradiated to areas other than the stone are reduced. can do.

Furthermore, by replenishing the coupling device with liquid when the intensity of the reflected wave from the body surface exceeds a set value, it is possible to maintain good contact between the coupling device and the patient.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a stone crushing device according to an embodiment of the present invention, and FIG. 2 is a time chart for explaining its operation.
Figure 3 is a diagram showing the situation of shock wave obstacles inside the body, Figure 4 is a time chart to explain the operation when reflection from obstacles inside the body is also considered, and Figure 5 is an electromagnetic induction type shock wave source. FIG. 6 is a diagram showing the main structure of an embodiment using an underwater discharge type shock wave source. 11... Piezo element 12... Coupling device 13... Bellows 14... Body surface contact membrane 15.
...Wednesday 16...Bed 17...Patient
18... Stone 19... Pump 20
... Water tank 21 ... Balsa 22 ... Switch 23 ... Low voltage power supply 24 ... High voltage power supply 25 ... Amplifier 26 ... Detection circuit 27 ...
・A/D converter 28...Memory 29...Digital integration circuit 30...Reflected wave intensity detection circuit 31...Controller 32...Keyboard 33.
... Display 34 ... Notification device 41 ... Rib 42 ... Lungs 51 ... Flat coil 52
... Insulation 'y-to 53 ... Conductive plate 54 ...
- Insulating sheet 55... Piezoelectric film 56... Piezoelectric layer 57.58... Electrode 59... Acoustic lens 6
1...Spheroidal reflector 62...Discharge gap 63...Piezoelectric sensor applicant's agent Patent attorney Takehiko Suzue

Claims (2)

[Claims] (1) In a lithotripter that crushes and treats stones by focusing and irradiating shock waves generated by a shock wave source outside the patient's body through a coupling device filled with a predetermined liquid to stones inside the patient's body, the shock waves generate pressure. a transmitting means for transmitting a low pressure wave into the body through the coupling device; a receiving means for receiving a reflected wave of the low pressure wave transmitted by the transmitting means; and the reflected wave received by the receiving means. Among them, a reflected wave intensity detection means for detecting the intensity of the reflected wave from a predetermined area in front of the convergence area of the shock wave, and an alarm when the intensity of the reflected wave detected by the reflected wave intensity detection means is equal to or higher than a set value. 1. A stone crushing device characterized by comprising a notification means that performs an operation. (2) In a lithotripter that crushes and treats stones by focusing and irradiating shock waves generated by a shock wave source outside the body on stones inside the body through a coupling device filled with a predetermined liquid, the shock waves generate pressure. a transmitting means for transmitting a low-pressure wave into the body through the coupling device; a receiving means for receiving a reflected wave of the low-pressure wave transmitted by the transmitting means; and a receiving means for receiving a reflected wave of the low-pressure wave transmitted by the transmitting means; The coupling device includes a reflected wave intensity detection means for detecting the intensity of reflected waves from near the patient's body surface, and a reflected wave intensity detection means for detecting the intensity of reflected waves from near the patient's body surface. A stone crushing device characterized by comprising a means for replenishing.