Laser assembly

FIELD: medical equipment.

SUBSTANCE: laser assembly can be used in operative urology, for example, for curing benign hyperplasia of prostate and in lithotripsy for curing urolithiasis. Laser assembly has at least first laser radiator intended for lithotripsy of gallstones and second laser radiator intended for cutting and coagulation of tissues. First laser radiator is made for transform of radiation into second harmonica. It has laser resonator on base of Nd:YalO3 crystal with modulation of Q-factor by shutter having damaged total internal reflection and with fiber-optic delay line. Laser radiator also has out-resonator radiation for transforming radiation into second harmonica of radiation at non-linear crystal to reach efficiency of transformation of 25% and higher. Second laser radiator has laser resonator on base of Nd:YAG crystal. Both radiators can be combined inside single laser assembly. Universal power source of pump lamps is used as well as integral control system and integral cooling system.

EFFECT: reduced cost of assembly; smaller sizes and weight.

12 cl, 4 dwg

 

The invention relates to medical equipment and can be used in operative urology, in particular, in the treatment of benign prostate hyperplasia (BPH) and lithotripsy in the treatment of urolithiasis (ICD).

Laser surgical methods for the treatment of urological diseases can be divided into two groups of interventions. The first group is associated with conducting impact on the soft tissues of the body for dissection, vaporization or coagulation. As examples of diseases that are successfully and widely used in these laser techniques include: benign prostatic hyperplasia (BPH), urethral stricture, bladder tumors and other Second group of interventions related to the need for the destruction of solid concretions with IBC.

One of the main reasons limiting distribution of laser treatments in urology, is the complexity of operation and the high cost of the proposed surgical lasers. Known laser system is effective for use in a range of tasks - in particular, or for cutting, vaporization and coagulation of tissue in the treatment of diseases such as BPH, or for crushing hard concretions at ICD, and the acquisition of clinics according to the separate installation for each of the areas p is imeneniya economicsi not justified.

In particular, in patent US 5593404 (Costello et al) describes a device based on Nd:YAG laser, with a wavelength of 1,064 μm, operating in the continuous mode of generation, with the output power of the radiation in the range from 40 watts to 90 watts. The device is used in the treatment of strictures of the urethra, bladder tumors, conducting interstitial coagulation, treatment of genital warts. The disadvantage of this device is that the efficiency of its use in urology limited to procedures that allow for deep, up to several millimeters, the penetration of radiation in biological tissue.

It is also known device US 6986764 (Davenport et al) is based on Nd:YAG laser operating in a quasi-continuous mode of generation, with generation of the second harmonic radiation, the radiation power up to 80 watts. Radiation 0,532 μm is more effective absorption coefficient of tissue prostate cancer than radiation 1,064 μm, the absorption of water slightly (μa=4,34×10-4cm-1[1]). As a result of exposure greater than when exposed to radiation 1,064 μm, the proportion of tissue subjected to ablation, and the depth of residual coagulated tissue does not exceed 1-2 mm, the Disadvantage of this device is that when the radiation parameters and the mechanism of interaction with tissue use is limited only by the scope of the tasks connected is conducting ablation of tissue. In urology, the device is used in the treatment of BPH.

There are also devices on the basis of pulsed Ho:YAG lasers with a wavelength of 2.1 microns, operating in free-running mode with output radiation power of up to 80 watts. Having a high absorption coefficient (μand=26,93 cm-1[2]), the radiation of the Ho:YAG laser is well absorbed by water contained in the tissues. Due to the low penetration depth of the radiation and of the independence of the absorption from the tissue contact dissection, vaporization and ablation of tissue using a Ho:YAG lasers are effective treatments in the treatment of several diseases. Strong absorption of radiation by the substance of the stone and the water present in them, allows the use of such lasers also in the fragmentation of stones in the ICD. However, the necessity of using high pulse energies up to 2.5 j with pulse durations up to several hundred microseconds and thermal destruction mechanism stones create a high risk of damage to surrounding stone tissue, resulting in the area of application of such devices is admittedly limited.

For use in lithotripsy preferred laser system, which is implemented not thermal, and acoustic mechanism of destruction of the stones. When the duration of the laser pulse from one to several microsecondregime stones occurs due to the generation of shock waves, propagating in the substance of the stone after the collapse of the cavitation bubble on the surface of the stone [3].

One of the first devices for laser lithotripsy were installed on the basis of dye lasers with lamp-pumped. They had the optimal duration of the radiation pulse in the range of 1-3 ISS, the wavelength 0,504 μm, with a local minimum absorption by oxyhemoglobin. The drawback of such lasers is that fragmentation do not lend themselves to all types of stones, and the operation of such lasers in the clinic has a high cost [4]. Use as the active medium toxic dyes creates additional difficulties due to the need for periodic change of the container with dye.

Developed cheaper, solid-state lasers based on different active media, generating pulses of microsecond duration. Known, in particular, the laser crystal of alexandrite US 5496306 (R. Engelhardt et al., publ. 24.11.1992), whose wavelength can be in the range of 0.7-1.0 μm and falls in the region of minimum absorption of the surrounding tissue. Second harmonic radiation is used to initiate laser spark on the surface of the stone. The pulse duration of 1.1 μs is implemented in the device by using a fast feedback controlling the transmittance of the shutter based on the cell Pockels. The disadvantage of the us the device is pickova the structure of the temporal profile of the pulse intensity modulated radiation up to 50%, that leads to damage to the optic tool in the delivery of radiation to the stone. In addition, the crushing process is the destruction of the distal end of the fiber in contact with the tissue, caused by inhomogeneities in the time profile of the pulse.

Known laser crystal Nd:YAG (EN 93003708, deacons GI and others, publ. 20.05.1995), using a similar method of lengthening the duration of generation of the pulse and the conversion to the second harmonic. As a shutter for controlling the speed of the output radiation from the resonator is used shutter with frustrated total internal reflection (shutter, ATR), synchronized with the power supply of the lamp pumping. Because the kinetics of development of the processes of pumping in crystal Nd:YAG is approximately 30 times faster kinetics of the development processes in the crystal of alexandrite, the control cavity with crystal Nd:YAG becomes even more difficult. The disadvantage of this device is complicated control scheme, low reliability in operation.

Also known laser-based ruby crystal (EN 95105018, Berenberg VA and others, publ. 10.06.1997). The wavelength of 0.65 μm of such a laser is safe for the surrounding tissue, microsecond pulse duration is implemented by increasing the length of the resonator due to multi-pass circuit between the system mirrors the Disadvantage of this device is the complexity of the design, the need for careful tuning and complexity of the operation.

Known laser crystal Nd:YAG with microsecond pulse duration and conversion of the radiation of the second harmonic (see US 5963575, G. Muller et al., publ. 05.10.1999). The duration of the pulse generation is achieved, as in the ruby laser, a change in the length of the resonator by making the optical delay. As the delay used fiber optic delay. First fiber optical delay element of the resonator to change the temporal characteristics of the laser radiation was used Dianov E.M. and others [6,7], and further studies performed in [8-11]. In the known laser pulse energy equal to 120 MJ, in a ratio of 20 MJ at the wavelength of the radiation 0,532 μm and 100 MJ at a wavelength of 1,064 μm. Q-switching is accomplished using a passive shutter, and the conversion to the second harmonic is vnutrirezonatornoe nonlinear crystal KTP. The disadvantage of this device is that disintegrate when exposed not all types of stones and the destruction efficiency of stones mixed composition of calcium oxalate monohydrate and dihydrate is 53.4%, struvite 68,1%, calcium phosphates 58,0% [12]. The main reason for this is the low energy pulse generation and transformation is Noah the second harmonic part of the radiation. The use of passive shutter, when the pumping of the active element to the level above the threshold, initiates the formation of pickaway patterns on the time profile of the pulse generation. The intensity modulation due to such a structure, with increasing pulse energy leads to the risk of damage to the optical elements of the resonator and fiber tool for delivering laser radiation to the stone.

The disadvantage inherent in all considered devices is that they can be used effectively either in operative urology or lithotripsy. It is also known device, uniting in one body by two powerful laser: Ho:YAG up to 80 W and Nd:YAG up to 100 watts ("VersaPulse PowerSuite boosts - Dual Wavelength Laser" site of the producer Lumenis Ltd. http://www.lumenis.com). In the known device the radiation with a wavelength of 2.1 microns provides the possibility of using it as the fragmentation of stones, and in contact tissue dissection, and radiation 1,064 μm - can be used for deep tissue freezing. The creation of the Ho:YAG lasers of this power requires the Association of two or more resonators operating at low frequencies, to obtain a high average radiation power and resolve problems with cooling and thermal effects in the active elements. The disadvantages of the devices in the first place can be called the high cost and risk of t is michelago damage to the surrounding tissue during lithotripsy.

The main task of the present invention was a device for influencing the solid stones with lithotripsy and soft tissue in operative urology, which would be deprived of most of the shortcomings noted above installations, as multi-functional and designed to address any one of these tasks.

This problem is solved by the fact that laser facility, containing at least the first laser emitter (lithotripter), designed for crushing stones, and the second laser emitter (scalpel-coagulator)intended for dissection and coagulation of tissue, electrically connected with the common power supply lamp pumping emitters and a single cooling system, and the controller with the ability to control the specified power supply and cooling system, according to the invention, the first laser emitter configured to convert radiation into a second harmonic and with the possibility of generating radiation with a pulse duration lying in the range of 0.5÷5,0 ISS, and includes a laser resonator based on the crystal Nd:YAlO3q-switched by a shutter with frustrated total internal reflection and optical fiber delay line, and unreasoningly Converter radiation of the second harmonic of the teachings on non-linear crystal with a conversion efficiency of at least 25%, and the second laser emitter configured to operate in a pulse-periodic mode with a maximum average output power up to 100 W, and includes a laser resonator based on the crystal Nd:YAG.

In the preferred case, in the laser cavity of the first emitter transducer radiation of the second harmonic is equipped with a stabilization system that includes coupled to the controller thermostat with the installed nonlinear crystal.

Preferably, in the laser cavity of the first emitter transducer radiation of the second harmonic is configured to implement the 90°th critical angle of synchronism with the focusing of the radiation in the specified nonlinear crystal.

In the particular case of the inverter radiation of the second harmonic as the nonlinear crystal can be used crystal KTiOPO4. At the same time as the output mirror in the laser cavity of the first emitter, it is preferable to use a polished end face of the nonlinear crystal KTiOPO4.

In the laser cavity of the first emitter, it is preferable to provide active q-switching, in which the duration of opening of the shutter is set to more than 2 microseconds, and the duration of the open state of more than 6 µs.

Preferably, in the laser cavity, the first is about the emitter fiber delay is set so that which one of the ends of the fiber delay is at a distance of the order of the diameter of the quartz veins fiber from the reflecting surface of a spherical mirror resonator, and the second end of the agreed upon output aperture with the aperture of the active resonator element.

Also preferably, in the laser cavity of the first emitter between the active element and the fiber delay was set polarization isolation on the basis of the Fresnel rhomb and polarizer.

Preferably, the laser system may be configured to connect individuality and further comprise a video processing module with individuality.

In addition, preferably laser installation can be performed with the opportunity to demonstrate the progress of surgical intervention in real time on the touch screen monitor connected to the video processing module, with simultaneous recording of video on mobile external storage device.

The use of the present invention podesteria active laser media Nd:YAlO3for lithotripter and Nd:YAG for scalpel-coagulant allows you to apply universal power supply lamp pumping, unified management and control and a single cooling system, and also to reduce the cost of installation, and its dimensions the weight. The specified pulse duration of the radiation generated in the first emitter, is optimal from the point of view of reliability and efficiency of the installation when the pulse durations of less than 0.5 μs substantially increases the risk of damage to the optic catheter for delivery of radiation to the surface of a stone, and at duration more than 5 µs decreases the efficiency of the energy input in the generation of the shock wave and, consequently, decreases the efficiency of the fragmentation of concrements.

The power of the two lasers of different types are combined in the complex, provide a solution to problems in the whole range of tasks associated with dissection and coagulation of tissue and disposal of solid concretions in the treatment of urolithiasis. This arrangement provides the advantage of versatility of installation, which is achieved by the possibility of combining different modes of operation and parameters of the output radiation, its constituent lasers: a scalpel-coagulant and lithotripter.

The invention is illustrated hereinafter in more detail a specific example of implementation with reference to the accompanying drawings, which depict:

- figure 1 - block diagram of the installation;

- figure 2 - optical scheme of the installation;

- figure 3 - site of a spherical mirror lithotripter;

- figure 4 - temporal profile p is lowering the shutter the ATR and the pulse shape generation.

As shown in the block diagram, figure 1, the installation according to the invention consists of two laser emitters with active elements crystal Nd:YAlO31 and Nd:YAG 2. Pumping of active elements 1 and 2 is the power lamp pump 5 is controlled by a controller 8. The q-switched resonator in the first emitter (lithotripter) is performed by the modulator 3 on the basis of the shutter with frustrated total internal reflection (shutter, ATR), the control unit which is connected to the controller 8. Nerezonansnoe converting radiation lithotripter second harmonic is nonlinear crystal located in thermostat 4. Cooling system 6 with air-water heat exchanger closed loop provides cooling active members 1 and 2 and lamp pumping. Measurement and control of the output beam parameters is performed with the help of a group of components 11, on the basis of the photodiodes. Present in shown in the figure 1 example, the touch monitor 9 serves as a control panel to manage user installation, and as a video monitor to display the signal individuality, processing which is performed by the processing unit 10. The video processing module 10 can serve not only to display the progress of the intervention in real time on the screen of the monitor 9, and m is can record the video on an external mobile data carrier (for example, on a portable hard drive connected using a USB interface)for archiving or further analysis.

In the above analog (laser lithotripter, US 5963575, G. Muller et al.) the q-switched resonator by using the passive gate that leads to the formation of pickaway the temporal structure of the pulse generation. The increase in pulse energy generation under such conditions leads to an increase in the modulation intensity time profile of the pulse and the risk of damage to the optical elements of the resonator and fiber tool. On the other hand, the low density of the radiation intensity in a nonlinear crystal KTP, due to the beam size and pulse duration of 1 μs, when the intracavity conversion of the radiation of the second harmonic gives a low conversion efficiency. Limiting the total output pulse energy and low efficiency of the conversion yield of the emitter total energy of the pulse is equal to 120 MJ and share the converted radiation 20 MJ.

In contrast to the specified analog in the claimed invention to increase the output pulse energy and increase the efficiency of the conversion scheme of the laser resonator, which allows to obtain single pulse generation with a smooth temporal profile of the radiation. In the profile is from the specified analog implemented active q-switched resonator shutter the ATR. To achieve efficient frequency conversion of the radiation with power density of <1.0 MW/cm2it requires focusing in a nonlinear crystal. At angles of focus of radiation, equal to several degrees, it is necessary to implement non-critical on both corners of the synchronism - 90° of synchronism. Non-critical angle phase matching in the crystal crown-rump length (KTiOPO4for radiation 1,0796 μm is sufficient to focus the angular width when heating the crystal to a temperature of 54°width angles of synchronism becomes maximum and is equal to 4 and 12 degrees for angles of synchronism ϕ and θ respectively. Unlike analogue implemented nerezonansnoe converting radiation of the second harmonic with a non-critical angle, 90°m synchronism with focus radiation in a nonlinear crystal KTP.

Figure 2 shows the optical layout of the device.

The laser resonator of the first emitter (lithotripter) collected on the basis of the active element of the crystal Nd:YAlO327. A change in the effective length of the resonator is made through the installation of fiber optic delay 21. Approval of the aperture of the radiation at the output end of the fiber optic delay 21 with the aperture of the active element 27 is performed by the lens 22, the focal length of which in this particular case was chosen equal to 18 mm, the Return of the teachings, released from the opposite end of the optical delay 21 is a spherical mirror 20. In the described preferred case of the invention, the fiber end (diameter quartz veins d=300 μm) preferably is located at a small distance Δ from the reflecting surface of the mirror 20, is equal to the diameter quartz veins fiber: d≈Δ. The radius R of the spherical mirror surface 20 is selected so that R>>d, and the choice of specific values of the radius R is determined by the design of the mount mirror. As shown on figure 3, item 20.1 connector fiber lies on the spherical mirror surface and has a diameter D. the values of D and R define the gap Δ, between the reflecting surface of the mirror 20 and the end face of the fiber. The size of the reflective coatings on the mirror 20 must be less than D, the inner diameter of the part 20.1, to prevent contamination or damage during Assembly. When the values of D=8,6±0.1 mm and R=36 mm gap between the end face of the fiber and the reflecting surface of the fiber is Δ=257±7 μm. Experimentally determined that when the specified value Δ, fiber type quartz/quartz, with core diameter of 300 μm, fiber length of 70 m and the wavelength 1,0796 µm numerical aperture of the radiation emerging from the end face of the fiber in the direction of the active element 27, the level of 96% of the total energy is equal to NA=0,16. The bend radius of the fiber, collapsed in the ring, equal to 150 mm If in the focal plane of the lens 22 to set the aperture 23 with a diameter corresponding to the same numerical aperture of NA=0,16, she, in turn, will cut off the radiation at high angles propagating in the resonator in the direction of the optical delay. The site of the spherical mirror 20 can serve as a selector angles due to the increase in losses for radiation having large values of numerical aperture when returning in the optical delay.

Further, the rotary mirror 26 and 28 serve to reduce the size of the resonator lithotripter, while the lens 29 (for example, with a focal length of 99 mm) is designed to focus the radiation on the surface of the front end face of the nonlinear crystal 31, which may be selected crystal crown-rump length (KTiOPO4). The front face of the crystal KTR 31 is a polished surface, without coatings, and serves as an output mirror of the resonator reflectivity R≈7%. When this lens 29 is constructed image of the aperture 23 on the surface of the face of the crystal with the reduction ratio, for example M≈a 3.5. The angle of focus of radiation does not exceed the width of the corners of the non-critical phase matching in the crystal 31, and the peak energy density on the crystal surface 31 does not exceed 18 j/cm2that is below the threshold values of surface damage to the crystal KTR [13].

The q-switched resonator of the first emitter is bolt the ATR 30, located between the lens 29 and the crystal 31. The parameters controlling the shutter of ATR and its characteristics, it is preferable to select such a way that the open state of the shutter 30 was 10-15 times more time to complete pass of the resonator, and the opening time of the shutter 30 in two times the length of the pulse generation. In this particular case, the execution was set the duration of the open state of the shutter the ATR 30 t≥6 microseconds and the duration of opening of tf≥2 ISS. 4 shows the characteristic curve of the transmittance of the shutter the ATR and the temporal shape of the laser pulse generation.

Between the active element 27 and the end face of the optical fiber delay set the polarization separation on the basis of the diamond Fresnel polarizer 24 and 25. Polarization isolation serves to suppress generation that may occur in the cavity formed between the end face of the nonlinear crystal 31 and the end face of the optical fiber delay 21, preventing the formation of the corresponding resonators. Pulses of short duration 10-100 NS, in the case of oscillation in such a resonator, modulate the temporal intensity profile microsecond pulse, which may result in destruction of the optic is a separate estimate of the resonator.

For the chosen parameters of the optical resonator circuit of the first emitter maximum energy of the laser pulse at its output amounted in this example 186 MJ and the pulse duration at half-height of 0.92 µs. The optimum temperature in thermostat 4 crystal KTR 27 to implement non-critical at the corners of synchronism was set equal 54,0°±0,1°C. If the length of the crystal is equal to 24 mm, the proportion of energy converted into the second harmonic radiation was 57 MJ (≈31%).

Further, the input system of two lenses 32 and 34 is intended to enter the radiation of two wavelengths in attachable to the first emitter fiber tool (fiber catheter) 37. Part of the radiation plate 33 is given for control of output pulse energy on a group of components, where 34 and 36 Energomera-based photodiodes, and 35 - dichroic mirror. Lenses 32 (with a focal length of 114 mm) and 34 (with a focal length of 18.4 mm) optimized to minimize spherical and chromatic aberration for two wavelengths: 1,0796 μm and 0,5398 μm. With their help, the image spots of the laser beam in the plane output mirror of the resonator, on the face of the crystal KTR 31 is constructed in the plane of the input end of the fiber tool 37 with reduction factor about 6.7. The spot diameter of a laser beam on the input side in the fiber tool is 240 μm in diameter quartz veins fiber 300 μm. The effectiveness of input radiation in fiber, taking into account losses on the Fresnel reflection at the fiber ends of the tool and losses on lenses, is 91% for radiation with a wavelength of 1,0896 microns and 85% in the wavelength 0,5396 microns.

Next, as shown in figure 2, the second emitter (scalpel-coagulator)intended for dissection and coagulation of tissue, includes a resonator on the basis of the active element of the crystal Nd:YAG 42 size ⊘6,3×100 mm as "deaf" mirrors of the resonator of the second emitter used spherical mirror 41 with a coefficient of reflection of radiation with a wavelength of 1,064 μm, equal to 99.9%, and the radius of curvature of the surface ≈2000 mm Flat mirror 44 with the transmittance of radiation ≈50% is output mirror of the resonator. Flat mirror 43 is used as a swivel to reduce the size. Enlightened ploskoparallel plate 45 serves to drain the part of the radiation in Energomera 46, to control the output energy of the radiation pulse. Two-component lens 47 with a focal length of 18 mm is used for input radiation attachable to the second emitter fiber catheter 48.

The installation can be used as follows.

For fragmentation of stones (in particular, in the treatment of IBC) laser installation mode of operation in which it participates that is are first laser emitter (lithotripter). Fiber catheter 37 is held in the working channel of the endoscopic surgical instrument (for example, ureteroscopy). In real-time under direct visual control, when displaying the intervention process using individuality on the monitor 9 is a contact action of laser radiation on the surface of the stone. In the specific implementation shown in the drawings, the maximum output energy of the laser pulse at the distal end of the fiber 37 of the first emitter with a diameter quartz veins 300 μm was 165 MJ, of which 49 MJ - energy radiation pulse at the wavelength of the second harmonic. The duration of the output pulse is 0,92 ISS. When contact influence in vitro on the stones in the range pulse energy of 120 MJ to 165 MJ were successfully destroyed the stones of different chemical composition.

When using the setup in operative urology for dissection and coagulation of tissue mode, which involves only the second emitter (scalpel-coagulator). The delivery of radiation to the area of influence is fiber catheter 48 as at endoscopic intervention, and at the open pit operations. Upon contact of the distal end of the fiber 48 with fabric is the dissection of the tissue due to the photothermal effect, partly is the vaporization and coagulation of tissue along a zone of dissection. For example, in the treatment of stricture of the urethra is her contact dissection distal end of the fiber catheter 48 with the output power of laser radiation ˜40 watts. When removing the distal end of the fiber 48 from the surface of the wound area is remote coagulation of tissue. For example, in the treatment of superficial bladder tumors is the coagulation of the tumor radiation power output of 60 watts.

In conclusion, it should be noted that the above example is provided to better understand the essence of the claimed invention and should not be viewed as limiting the volume of claims. The specialist will be clear and other special cases of the invention, is not beyond the requested legal protection is defined only by the attached claims.

Sources of information

1. R.M.Pope and E.S.Fry, "Absorption spectrum (380-700 nm) of pure water. II. Integrating cavity measurements" App. Opt., 36, 8710-8723 (1997).

2. G.M.Hale and M.R.Querry, "Optical constants of water in the 200 nm to 200 μm wavelength region," App. Opt., 12, 555-563 (1973).

3. K.Rink, G.Delacretaz, R.P.Slathe. "Fragmentation process of current laser lithotriptors" Lasers in Surgery and Medicine,, v.16, n.2, pp.134-146 (1995).

4. M.A.Imamoglu, H.Bakirtas, O.Yigitbasi, H.Ersoy, N.Sertzelik "Use of pulsed dye-laser lithotripsy in the treatment of ureteral stones and its results" Urologia v.67, no. 1 (2000).

5. Patterns, Skiset, Laskarina, Navco, Vis. "Laser with a fiber resonator", "Quantum is electronics", 3, No. 11, str-2505 (1976).

6. Patterns, Skiset, Laskarina, Navco, Vis. "Raman laser with a fiber resonator", in Quantum electronics 5, No. 6, str-1309 (1978).

7. S.K.Isaev, L.S.Kornienko, N.V.Kravtsov, N.M.Naumkin, B.G.Skuibin, V.V.Firsov YU.P Yatsenko. "Mode self-locking in solid-state lasers with long resonators". J. Opt. Soc. Am., v.68, No.11, pp.1621-1622 (1978).

8. Amicably, Skiset, Laskarina. "Selection mode and the frequency of the laser with the light guide resonator", in Quantum electronics 8, No. 12, str-2697 (1981).

9. Masataka Nakazawa, Masamitsu Tokuda, Naoya Uchida. "Lasing characteristics of a Nd3+:YAG laser with a long optical-fiber resonator". J. Opt. Soc. Am., v.73, No. 6b, pp.838-842 (1983).

10. Patterns, Amicably, Skiset, Laskarina. "Ring-garnet laser with a fiber resonator", in Quantum electronics 11, No. 8, str-1510 (1984).

11. Patterns, Skiset, Laskarina, Via, Uperenko. "Synchronizing component of the SBS in fiber laser with a resonator", in Quantum electronics 16, No. 1, p.5-6 (1989).

12. S.Lahme, E.Eipper, A.Stenzl. "Effect of laser lithotripsy by means of frequency doubled dual-pulse Nd:YAG laser (FREDDY) - An in vitro study with natural urinary calculi". European Urology Supplements, v.3, No.3, pp.189-190 (2004).

13. Abrosimov S.A., Grechin YEAR, Kochiev became popular, Maklakov POSTGRADUATE, Semenenko Century "SHG crystal crown-rump length of monopulse microsecond duration". Quantum electronics, 31, No. 7, str-646 (2001).

1. Laser unit, containing at least the first laser emitter is the output for crushing stones, and the second laser emitter designed for dissection and coagulation of tissue, electrically connected with the common power supply lamp pumping emitters and a single cooling system, and the controller with the ability to control the specified power supply and cooling system, characterized in that the first laser emitter configured to convert radiation into a second harmonic and with the possibility of generating radiation with a pulse duration of 0.5÷5.0 ISS and includes a laser resonator based on the crystal Nd:YAlO3q-switched by a shutter with frustrated total internal reflection and optical fiber delay line, and unreasoningly Converter radiation of the second harmonic radiation in a nonlinear crystal with a conversion efficiency of at least 25%, and the second laser emitter configured to operate in a pulse-periodic mode with a maximum average output power up to 100 watts and includes a laser resonator based on the crystal Nd:YAG.

2. Laser apparatus according to claim 1, characterized in that the laser cavity of the first emitter transducer radiation of the second harmonic is equipped with a stabilization system that includes coupled to the controller thermostat installed in it nelin the emergency crystal.

3. Laser apparatus according to claim 1 or 2, characterized in that the laser cavity of the first emitter transducer radiation of the second harmonic is configured to implement the 90°th critical angle of synchronism with the focusing of the radiation in the specified nonlinear crystal.

4. Laser apparatus according to claim 1 or 2, characterized in that the transducer radiation of the second harmonic as the nonlinear crystal used crystal KTiOPO4.

5. Laser apparatus according to claim 3, characterized in that the transducer radiation of the second harmonic as the nonlinear crystal used crystal KTiOPO4.

6. Laser apparatus according to claim 4, characterized in that as the output mirror in the laser cavity of the first emitter used polished end face of the nonlinear crystal KTiOPO4.

7. Laser apparatus according to claim 5, characterized in that as the output mirror in the laser cavity of the first emitter used polished end face of the nonlinear crystal KTiOPO4.

8. Laser apparatus according to claim 1, characterized in that the laser cavity of the first emitter provided with an active q-switching, in which the duration of opening of the shutter more than 2 microseconds, and the duration of the open state is more than 6 µs.

9. Laser apparatus according to claim 1, characterized in that in the laser cavity of the first emitter fiber delay is set so that which one of the ends of the fiber delay is at a distance of the order of the diameter of the quartz veins fiber from the reflecting surface of a spherical mirror resonator, and the second end of the agreed upon output aperture with the aperture of the active resonator element.

10. Laser apparatus according to claim 1, characterized in that the laser cavity of the first emitter between the active element and the fiber delay set the polarization separation on the basis of the Fresnel rhomb and polarizer.

11. Laser apparatus according to claim 1, characterized in that it is made with the possibility of connecting individuality and further comprises a video processing module with individuality.

12. Laser installation according to claim 11, characterized in that it is made with the ability to display the progress of surgical intervention in real time on the touch screen monitor connected to the video processing module, with simultaneous recording of video on mobile external storage device.



 

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18 cl, 3 dwg

FIELD: medicine.

SUBSTANCE: tissue with pathological changes is coated with fine particles of carbon dye. The coating is exposed to pulsed laser radiation. At the beginning of radiation, laser irradiation pulse power is set lower than the value expected for this threshold pathology. The repetition frequency of acoustic pulses generated by a surface thermal microexplosion and absorbing the laser emission of carbon dye particles is determined. It is compared to the laser pulses frequency. Laser pulses power is sequentially increased to a value at which the acoustic pulse frequency becomes equal to the repetition frequency of laser pulses. Irradiation is performed with this pulse power value. The device includes a laser operating in a pulse-periodic mode of laser radiation generation, a laser radiation operating parameters control unit, a laser radiation parameters measuring unit and an indication unit. It additionally contains an acoustic microphone, a selectable band-pass filter for a maximum range of 5-7 kHz, microphone signal amplifier and a two-input coincidence circuit, all connected in series. One of the coincidence circuit inputs is connected to the microphone signal amplifier output, the second icoincidence circuit input is connected to the laser pulses repetition driving frequency generator output, and output - to the laser radiation operating parameters control unit input and the indication unit.

EFFECT: increased efficiency of treatment and reduced probability of postoperative recurrence and scar development processes through implementation of objective selection and monitoring of the adequacy of defined laser radiation parameters, providing the process of shock wave destruction.

2 cl, dwg

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