JPH02161937A - Calcus breaking device - Google Patents

Abstract

PURPOSE:To change laser irradiation conditions according to the type of a calculus and to sufficiently enhance a breaking effect by changing the output, the repeating number, the wavelength, etc., of a pulsed laser beam obtained from a pulsed laser generator by analyzing a spectroscopic spectral image displayed on a TV monitor. CONSTITUTION:A laser irradiation condition setting device 27 measures and judges a calculus component from a calculus spectrum 26 and sets the laser wavelength, laser energy, a pulse repeating frequency, etc., appropriate for braking a calculus 2 according to the measured and judged result. A wavelength varying device 47 is the device for varying the laser wavelength and can vary the wavelength by signal from the laser irradiation condition setting device 27. When the calculus is irradiated with the laser beam, the calculus 2 evaporates from the irradiated surface and creates a sort of plasma state. At this time, an emission spectrum is observed from an element to compose the calculus 2. The component of the calculus 2 can be recognized by examining this emission spectrum. Thus, the laser irradiation conditions accordant with the type of the calculus can be set.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a device that uses laser light to crush stones that form inside the body, and in particular, determines the type of stone and optimizes laser irradiation accordingly. The present invention relates to a stone crushing device in which conditions can be set.

"Prior Art" It is known that components of secretions and excreta accumulate and precipitate in the kidneys, bladder, ureters, etc., forming stones and causing pain to the human body. Particularly in recent years, as the food intake has become more Westernized, stones have been occurring more frequently, and they have become a frequent disease in the urological field. Moreover, since it causes great pain to patients, an appropriate treatment method is desired.

Treatment methods include dissolving the stone with drugs, removing it through surgery, and applying shock waves to break it up into small pieces that are naturally excreted in the urine.A new treatment method is to irradiate the stone with pulsed laser light and use this energy to break up the stone. Natural excretion has been proposed, and some doctors are experimenting with it.

The conventional method of crushing stones using this laser will be explained with reference to FIG. 5, which is schematically shown. Stone formed in ureter 1 2
Opposite is an endoscope 9 with an optical fiber channel 6.7.8. Light from a white light source 3 (usually a xenon lamp) passes through a fiber channel 6 to illuminate the stone 2, and an image of the stone 2 obtained by reflected and scattered light passes through a fiber channel 8 to an observer 5. It has been reported and can be seen with the naked eye. Laser light pulses emitted from a laser light source 4 are sent to the stone 2 that has been targeted by this detection through a fiber channel 7 (this uses a quartz optical fiber inserted into the forceps hole of the endoscope 9). . The laser beam irradiates the surface of the stone 2, and its energy breaks it into small pieces. The laser used is a YAG laser (wavelength: 1.06 μm) or a visible light dye pulse laser (wavelength: 504 nm).

"Problem to be Solved by the Invention" When using the above YAG laser, stones are destroyed by the thermal energy of the laser, but since this YAG laser emits infrared light with a wavelength of 1.06 μm, where is the laser beam? It is difficult to tell which is being irradiated. If nearby living tissue is irradiated, there is a great risk of tissue damage or perforation.

The stone crushing process using dye pulsed laser light is said to be as follows. When the laser beam is irradiated, the surface of the stone is heated and the tiny stone particles are evaporated and released. These microparticles absorb the laser light, heat up further, and emit electrons, creating plasma. This plasma absorbs the laser light and begins to expand rapidly, generating strong pressure waves that destroy the stone.

The light absorption of hemoglobin in red blood cells in the blood is at wavelength 5.
The laser beam of 504 nm is selected because it shows a minimum around 0.04 nm. In other words, it is said that by using this laser, it is possible to crush stones without damaging living tissue.

This 504 nm laser light pulse crushes the stone by YA
It is more effective (much safer) than that using a G laser, but the effectiveness varies depending on the type of stone. For example, calcium oxalate (Ca
C20, ) stones are easy to fracture with a 504 nm laser, but calcium phosphate (C20,
aF22) is less susceptible to fragmentation than calcium oxalate. Other types of stones include magnesium phosphate, ammonium phosphate, cystine, etc., but the degree of fragmentation varies. In particular, cystine is not easily crushed by 504 nm laser light.

The present invention aims to sufficiently improve the crushing effect in stone crushing using pulsed laser light by changing the laser irradiation conditions depending on the type of stone.

"Means for Solving the Problems" The present invention provides an apparatus for monitoring a stone with white light and crushing it using a laser beam, including a white light source that emits pulsed white light for stone illumination necessary for monitoring the stone; A pulsed laser generator that emits pulsed laser light necessary for crushing a stone; and an endoscope that transmits the pulsed white light, the pulsed laser light, and the detection light obtained when the stone is irradiated with these lights. , a light splitter that divides the detection light transmitted from the endoscope into two; a spectrometer for spectrally dispersing one of the divided lights; and a spectrometer for doubling the spectral image obtained by this spectrometer. an image multiplier, an image pickup tube for capturing an image obtained by the image multiplier, and a TV camera for capturing a stone image obtained by the other light divided by the light splitter; a processor that processes signals from the image pickup tube and the TV camera and sends a video signal to a TV monitor; a TV monitor that displays a 1-spectrum image of the stone image based on the video signal sent from the processor; and the pulsed laser generator. The output, repetition rate, wavelength, etc. of the pulsed laser beam obtained from the device are determined by the above T.
The device is equipped with a laser irradiation condition setting device for changing by analyzing the spectral image displayed on the V monitor.

``Work'' When a stone is irradiated with laser light, the stone evaporates from the irradiated surface, creating a kind of plasma state.

At this time, an emission spectrum is observed from the elements that make up the stone (this is known as the "laser microprobe method"). Therefore, by examining this emission spectrum, the constituent components of the stone can be known, and a laser wavelength suitable for these constituent components can be set. Since actual stones contain various elements, it is necessary to research in advance which wavelength is most suitable for the composition ratio of those elements (which has the effect of crushing the stone). In order to prevent damage to living tissues by laser light, it is desirable that the laser wavelength be in the range of about 450 to 510 nm, where tissue absorption is low, so the actual laser irradiation wavelength is selected within this range.

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

In FIG. 1 showing the overall view of the device according to the present invention, an endoscope (9) is inserted into the ureter (1), and a stone formed inside the ureter (1) is inserted.
2) with the tip of this endoscope (9) facing. This endoscope (9) includes an optical fiber channel (6) that passes pulsed light (12) from a pulsed white light source (3) (which uses a Xe flash lamp) and a pulsed laser generator (4). ) and an optical fiber channel (7) that passes the laser light (11) from the stone (11), and an optical fiber channel that is made by bundling a number of fibers that pass the detection light (13) obtained from the stone (2) during laser light irradiation. (8) is included as a configuration. The number of the optical fiber channels (6) may be one, or two as shown in FIG. 2 may be used. The pulsed white light concretion (2
), the amount of light irradiated increases, resulting in a brighter image. The optical fiber channel (7) is connected to the forceps hole (1) of the endoscope (9) so that it can be replaced when damaged by laser light.
0). (14) is a beam splitter, and this beam splitter (14) passes the detected light (13) obtained from the stone (2) through the optical fiber channel (8) to the color TV camera (23) and the spectrometer (16).
This is for dividing and sending. One of the detection lights (13) split into two by the beam splitter (14) is passed through the condenser lens (15) to the entrance slit (
16a). This entrance slit (16a)
The detection light that has passed through is reflected by a reflecting mirror (17) and enters a concave diffraction grating (18), and the diffracted light that is separated here is passed through an image intensifier (hereinafter abbreviated as I-). 1 tube) (19) is imaged on the photocathode.

That is, the slit-shaped spectrum array of the spectrometer (16) is distributed on the photocathode of the II tube (19). This I
The I tube (19) emphasizes the image of the spectral train and forms the image on the phosphor screen on the emission side. This image is captured by an image pickup tube (20), and its output signal is processed by a processor (21) and then sent to a TV monitor (24) where the stone spectrum (26
) is displayed. On the other hand, the other detection light split by the beam splitter (14) is sent to the TV camera (23).

At this time, the lens (22) is connected to the optical fiber channel (8).
) The stone image (25) sent by the TV camera (
23) for forming an image on the photocathode. The output signal of the TV camera is processed by a processor (21) and then sent to a TV monitor (24) where a stone image (25) is displayed. Thus, two images are displayed on the TV monitor (24) by the processor (21), namely the stone image (25) and the stone spectrum (26).

The pulsed laser generator (4) and the pulsed white light source (
The timing of step 3) is controlled by a timing circuit (28). That is, the laser light (11) and the white light (12) are not emitted at the same time.

Emitted alternately in time. This is the timing circuit (2
8) is controlled by a trigger signal issued from. If two lights are emitted at the same time, the white light reflected from the stone (2) through the fiber channel (8) and the detection light emitted from the stone (2) by laser irradiation will be The tubes (19) are reached at the same time. Since the amount of reflected white light is greater than the detection light, the detection light is buried in this white light, making it difficult to detect the spectrum of the stone (2). Damaged by reflected light. To avoid this problem 2.
The two lights are emitted alternately. The gate circuit (29) outputs a gate signal that prevents the II tube (19) from operating when the reflected white light enters the II tube (19). By this gate signal, when reflected light enters the II tube (19), the voltage applied to the photocathode is cut, and the I
The multiplication function of the I tube (19) is stopped.

In Figure 4, (a) shows the emission spectrum of the laser beam (11), (b) shows the emission spectrum obtained by irradiating the laser beam (11), and (c) shows the temporal relationship of the white light (12). In this example, the pulse repetition frequency is 10 Hz.

Further, the laser light pulse width is about 1 μsec, and the white light pulse width is about 20 m5ec. (27) is a laser irradiation condition setting device, which measures and determines the stone components from the stone spectrum (26) and accordingly sets the laser wavelength, laser energy, pulse repetition frequency, etc. suitable for crushing the stone (2). This is for setting.

FIG. 3 shows a specific example of the configuration of the pulse laser generator (4) used in the apparatus of the present invention.

The laser head (40) has an inner surface finished to be highly reflective, and a flash lamp (41) and a cell (42) are housed inside. Among these, the cell (42) has a dye solution inlet (43) and a dye solution outlet (44), from which the dye solution that generates laser light flows,
And it flows out. On the axis of the cell (42) (which coincides with the laser optical axis), there are total reflection mirrors (45) at the rear and front, respectively.
) and a partially reflective transmitting mirror (46) are disposed, and when the flash lamp (41) discharges light with electric energy supplied from the power source (48), the cell (42)
) is excited to emit fluorescence. The fluorescence from this dye undergoes multiple reflections between the total reflection mirror (45) and the transmission mirror (46), the light intensity increases and becomes a laser beam (11), which passes through the transmission mirror (46) and passes through the transmission mirror (46). It is introduced into the optical fiber channel (7) shown in FIG. Although not shown, the flash lamp (41) needs to be water-cooled in order to operate stably over a long period of time. The wavelength variable device (47) is for varying the laser wavelength, and the wavelength can be varied by a signal from the laser irradiation condition setting device (27) (the details of the wavelength variable device (47) will be explained later).

The pulsed laser generator (4) is configured to be able to use three types of dyes. That is, (49), (50), (51), (52) of the dye solution supply system
), (53), (54).

(55), (56), and (57) are electromagnetic valves, and the corresponding switches (58) and (59) are respectively
) , (60) , (61L (62) , (6
3).

The opening/closing operations of (64), (65), and (66) result in energization or power outage, and the opening/closing of the electromagnetic valve is controlled. Between the electromagnetic valves (49) and (50), (51) (
52) between (53) (54) between (ss) (56)
The liquid reservoirs (67), (68), (69), and (70) between each contain a cleaning liquid (methyl alcohol), a first dye solution, a second dye solution, and a third dye solution (the first
Methyl alcohol is used as a solvent for the dye, second dye, and third dye). Among these, the liquid reservoir (68) (
69) In (70), the dye solution is cooled for stable laser oscillation. In addition, supply tanks (71) (72
) (73) and (74) are prepared to replenish the cleaning solution (methyl alcohol), first dye, second dye, and third dye solutions, respectively, and when the dye deteriorates, replace it with a new one. Supply tanks (71) (72) are supplied from here when the need arises (not shown)
(73) (74) and liquid reservoir (67) (6g) (
69) (70) are connected to each other by electromagnetic valves, and when necessary, the valves are opened to supply new liquid.

Next, the operation of this dye solution supply system will be explained.

When performing laser oscillation with the first dye, the electromagnetic valve (5
1) Open only (52) and open the other solenoid valve (49) (
50), (53) to (57) are closed. The first dye solution is transferred to the cell (42) and the liquid reservoir (6) by the circulation pump (76).
8), the flash lamp (41) discharges and emits light to excite the first dye, and a laser beam (11) is obtained. Next, when changing from the first dye to the second dye,
First, for cleaning, only the solenoid valves (49) and (50) are opened and the other solenoid valves are closed. A cleaning liquid (methyl alcohol) flows into the cell (42) and is cleaned. The methyl alcohol after cleaning is discarded into the waste liquid reservoir (75) by opening the electromagnetic valve (57). After that, the electromagnetic valve (49
) (50) Close (57) and open the solenoid valve (53).
Only (54) is opened, and the second dye is circulated through a circuit connecting the cell (42) and the liquid reservoir (69). The second dye laser beam (
11) is obtained. When obtaining the laser beam (11) using the third dye, the laser beam is obtained using the solution of the third dye after washing with the cleaning liquid (methyl alcohol) in the same manner as described above.

In the above embodiment, the cell (42) is a quartz tube with an inner diameter of 4 squares and a length of 20 mm, with quartz window plates attached to both ends, and the first, second, and third dyes are each made of Coumarin 504. ．． Coumarin 480. Coumarin 445 was used. Further, each dye was dissolved in methyl alcohol and used at a concentration of about 0.05 to 0.4 mM.

The wavelength variable device (47) is for varying the wavelength of laser light. Specifically, this is an acousto-optic filter.1 For example, a traveling wave of ultrasonic waves is created in a tellurium dioxide (TeO2) crystal, light is diffracted by this ultrasonic wave, and the wavelength of this diffracted light is changed depending on the frequency of the ultrasonic wave. Utilize uniquely defined properties. Therefore, the laser wavelength can be varied by changing the ultrasonic frequency using the relationship between the ultrasonic frequency and wavelength that is known in advance.

The wavelength of the laser is largely determined by the dye, but can be changed in detail by the wavelength variable device (47). For example, Coumarin 504. Coumarin 480, Coumarin 44
Each of the dyes No. 5 has an oscillation band in the range of 485 to 520.455 to 495° and 420 to 460 nm, but the laser wavelength can be fixed or varied within these bands using a wavelength tunable device (47). Can be done. The laser irradiation condition setting device (27) sets the ultrasonic frequency to vary the laser wavelength, the input energy of the flash lamp (41) to vary the laser light energy, the laser light pulse repetition frequency, etc. I do.

When a stone is irradiated with laser light, the stone (2) evaporates from the irradiated surface, creating a kind of plasma state. At this time, an emission spectrum is observed from the elements constituting the stone (2). This is a technique known as "laser microprobe method."

Therefore, by examining this emission spectrum, stones (2
), it is possible to set a laser wavelength suitable for this component. Since an actual stone (2) contains various elements, it is necessary to investigate in advance which wavelength is most suitable for the composition ratio of those elements, that is, whether it has the effect of crushing the stone. In order to prevent damage to living tissues by the laser beam (11), it is desirable that the laser wavelength be in the range of about 450 to 510 nm, where tissue absorption is low, so the actual laser irradiation wavelength should be within this range. are selected taking into consideration.

When observing the stone spectrum (26) on the TV monitor (24), a strong spectrum can be obtained by focusing and irradiating the surface of the stone (21) with laser light (11). For this purpose, it is preferable that the tip of the optical fiber (7) has a convex lens shape and can condense the laser beam (11).

Further, the laser wavelength for observing the calculus spectrum (26) may be any of those obtained from the first dye, the second dye, and the third dye (the spectrum can be obtained from any of them).

"Effects of the Invention" Since the present invention is configured as described above, it has the following effects.

1) The type of stones inside the body can be investigated without removing them from the body.

2) When crushing stones, laser irradiation conditions can be set according to the type of stone using a method that is safe for the human body, so the stones can be crushed efficiently in a short time, reducing patient pain.

3) Capable of component analysis and crushing of urinary stones, gallstones (gallstones), etc.

Although the example described above shows a case in which three dyes are provided, the number of dyes can be increased or decreased as appropriate depending on the situation without departing from the spirit of the present invention.

Further, in the embodiment described above, an acousto-optic filter was used as the wavelength variable device (47) of the laser, but other types of filters may be used. For example, a dispersive element such as a diffraction grating or a prism may be used. In this case, a mechanism (for example, a motor drive mechanism) for changing the angle at which light is incident on the diffraction grating or prism in response to a signal from the laser irradiation conditions is used when tuning the wavelength.

Although methyl alcohol was used as the dye washing liquid in the above embodiments, other liquids (ethyl alcohol, water, etc.) may be used.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of a stone crushing device according to the present invention, Fig. 2 is a perspective view of an endoscope, Fig. 3 is a block diagram of a pulsed laser generator, and Fig. 4 is a pulse waveform diagram. ,
FIG. 5 is an explanatory diagram of a conventional device. (1)...Ureter, (2)...Stone, (3)...Pulsed white light source, (4)...Pulsed laser generator,
(5)... Observer, (6) (7) (8)... Optical fiber channel, (9)... Endoscope, (10)...
Forceps hole, (11)... Laser light, (12)... White pulsed light, (13)... Detection light, (14)... Beam splitter, (15)... Condenser lens, (16
)...Spectroscope, (16a)...Incidence slit, (1
7)...reflection fi, (18)...concave diffraction grating,
(19)...image intensifier (II) tube,
(20)...Image tube, (21)...Processor, (
22)...Lens, (23)...TV camera, (24)
)...TV monitor, (25)...stone statue, (26)
... Stone spectrum, (27) ... Laser irradiation condition setting device, (28) ... Timing circuit, (29) ...
・Gate circuit, (40)...Laser head, (41)
... Flash lamp, (42) ... Cell, (43
)...Dye solution inlet, (44)...Dye solution outlet, (45)...Total reflection mirror, (46)...Transmission mirror, (47)...Wavelength variable device, ( 48)...power supply,
(49) to (57)...Solenoid valve, (58) to (
66)...Switch, (67)-(70)...Liquid reservoir, (71)-(74)...Replenishment tank, (75)-
... Waste liquid reservoir, (76) ... Circulation pump,

Claims (6)

[Claims] (1) A device that uses laser light to crush stones while observing them under white light irradiation, which includes a white light source that emits pulsed white light for stone illumination necessary for monitoring the stones, and a white light source that emits pulsed white light for stone illumination, which is necessary for monitoring the stones. a pulsed laser generator that emits a pulsed laser beam; an endoscope that transmits the pulsed white light, the pulsed laser beam, and detection light obtained when a stone is irradiated with the pulsed white light; a light splitter that splits the detected light into two; a spectrometer that spectrally spectrally spectra one of the split lights; and an image multiplier that doubles the spectral image obtained by the spectrometer; An image pickup tube for capturing the image obtained by the image multiplier, a TV camera for capturing the stone image obtained by the other light split by the light splitter, and the image pickup tube and the T.
A processor that processes signals from the V camera and sends video signals to a TV monitor, a TV monitor that displays stone images and spectral images based on the video signals sent from the processor, and images obtained from the pulsed laser generator. A stone crushing device comprising a laser irradiation condition setting device for changing the output, repetition rate, wavelength, etc. of the pulsed laser beam by analyzing the spectral image displayed on the TV monitor. (2) The pulse laser generator is a dye laser light source that can emit laser light from the dye by exciting a dye solution contained in a cell with a flash lamp, and has a dye solution inlet attached to the cell. A fluid circuit is provided between the dye solution circulation pump and the dye solution outlet, a dye solution reservoir, and valves located before and after the dye solution reservoir for opening and closing the flow of the dye solution or stopping the flow of the dye solution. The stone crushing device according to claim (1), characterized in that: (3) A dye distribution system consisting of a combination of a dye solution reservoir and valves connected before and after the dye solution reservoir is provided for each different dye, and these are connected in parallel. The stone crushing device according to claim (2), characterized in that: (4) A combination of a dye solution reservoir and a valve connected before and after the dye solution reservoir is connected in parallel to the dye flow path, and a combination of a dye cleaning solution reservoir and a valve connected before and after the dye solution reservoir. The stone crushing device according to claim (2), characterized in that: (5) The valves disposed before and after the dye solution reservoir and the dye cleaning solution reservoir are electromagnetic valves that are opened and closed by electric signals. lithotripter. (6) The stone crushing device according to claim (1), wherein the pulsed white light and the pulsed laser light are emitted alternately in time.