Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
  • A61F9/007—Methods or devices for eye surgery
  • A61F9/008—Methods or devices for eye surgery using laser
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
  • A61F9/007—Methods or devices for eye surgery
  • A61F9/008—Methods or devices for eye surgery using laser
  • A61F9/00802—Methods or devices for eye surgery using laser for photoablation
  • A61F9/00804—Refractive treatments
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
  • A61F9/007—Methods or devices for eye surgery
  • A61F9/008—Methods or devices for eye surgery using laser
  • A61F2009/00853—Laser thermal keratoplasty or radial keratotomy
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
  • A61F9/007—Methods or devices for eye surgery
  • A61F9/008—Methods or devices for eye surgery using laser
  • A61F2009/00861—Methods or devices for eye surgery using laser adapted for treatment at a particular location
  • A61F2009/00872—Cornea
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F9/00—Methods or devices for treatment of the eyes; Devices for putting-in contact lenses; Devices to correct squinting; Apparatus to guide the blind; Protective devices for the eyes, carried on the body or in the hand
  • A61F9/007—Methods or devices for eye surgery
  • A61F9/008—Methods or devices for eye surgery using laser
  • A61F9/00825—Methods or devices for eye surgery using laser for photodisruption

Definitions

• the present invention relates to an ophthalmological surgery device by photoablation, photodi ⁇ ruption or ultraviolet linear photodissociation of living tissues directly accessible, by means of ultra short pulses whose duration is from 10 to 100 nanoseconds, originating from a laser light source. consistent and intended in particular, but not exclusively, for corneal and vitreous surgery.
• a device emitting, at the output, in a spatial or temporal mode, radiation whose wavelength is in the ultraviolet and in particular included in the range of 150 to 215 nanometers.
• the radiation emitted must be outside the absorption band of human proteins and DNA deoxyribonucleic acid.
• the range of 230 to 260 nanometers should be avoided.
• a KRF laser with a wavelength of 247 nm. corresponded to a frequency of DNA and could have a carcinogenic effect by breaking molecular chains.
• the radiation is completely absorbed by the air and the addition of a vacuum radiation channel would prevent the permanent control necessary for precision surgery.
• Patent EP-A-0 007 256 describes an ophthalmological surgery device including a YAG laser (double garnet of yttrium and aluminum emitting pulses of a duration of the order of a few picoseconds with a length d wave of 1064 nanometers to achieve a closed globe endocular icosurgery.
• YAG laser double garnet of yttrium and aluminum emitting pulses of a duration of the order of a few picoseconds with a length d wave of 1064 nanometers to achieve a closed globe endocular icosurgery.
• the ultra-fast emission of a small amount of emerging energy and the high concentration of light on a microsurface are at the origin of the optical breakdown and the formation of a plasma followed by the development of responsible shock waves disruption of the target tissue, regardless of its chemical nature and regardless of any coloring or pigmentation.
• Argon lasers have also been used in continuous emission of light emitting radiation of 488 to 514.5 nanometers in order to carry out photocoagulations and krypton lasers of wavelength equal to 647 nm allowing photocoagulation of the choroid. through the retina itself.
• the cornea consists by weight of about 80% water and 20% protein.
• the problem of photoablation consists in carrying out a pure photodissociation of water without altering the proteins.
• a photodissociation a laser emitting in the blue, in pre 'presence of a metal catalyst with an energy of about 1.8 electron volt photon.
• catalysis causes an action on proteins, which is absolutely to be avoided.
• the introduction of a catalyst onto or into the retina can pose problems, the oxygen resulting from the dissociation of water recomposing with another constituent of the retina.
• the radial keratotomy must be extended to the DESMET membrane without reaching it, let alone the non-renewable endothelium.
• the incisions are made with a diamond knife. The results of this operation remain largely uncertain since, after a few incisions, the cornea deforms (corneal depression) so that, even with a knife fitted with a guard, the - ⁇ depth of incision can hardly be constant.
• US-A-4,461,294 (BARON) describes a device and a method intended for performing radial keratotomies by means of a tracer device including a dye (riboflavin) on the cornea.
• a tracer device including a dye (riboflavin) on the cornea.
• the marked lines are evaporated by means of an argon laser through a slit mask, the lines being drawn by a computer according to the change in convergence to be obtained.
• the dye having been introduced into the BOWMAN layer and into the stroma absorbs the light energy emitted by the laser, which causes the marked tissue to be cut.
• a first object of the present invention is a device making it possible to perform a photoablation of the cornea according to a defined configuration of incisions, performed simultaneously, or almost simultaneously, using a pulsed laser, without significant necrosis of the tissues ( epithelium, membrane of B0 MANN, stroma) at an exactly determined depth, making it possible to avoid the problems due to corneal depression and giving predictable and repetitive results.
• a second object of the present invention is a device delivering an output laser beam whose radiation is completely absorbed by the cornea and cannot in any case diffuse into other tissues: lens, retina, choroid or in the vitreous humor.
• a third object of the present invention is a device for multipurpose uses allowing various ophthalmic surgery operations to be carried out with a single device.
• the device for linear photoablation of living tissue comprising at least one laser source is characterized in that it comprises means for concentrating and focusing the beam emitted by the laser source, and means for spatiotemporal distribution of the beam output whose wavelength is between 150 and 220 nanometers and the energy between 100 and 1000 millijoules per cm2.
• this device can constitute, from a single source: a YAG photodisruptor laser operating in triggered (Q-switched) or thermal mode operating in "free running" mode, a photocoagulator argon laser, in particular an argon pulse laser for the treatment of glaucoma or a short ultraviolet laser for corneal or vitreous surgery.
• the original laser bar is a rectangular YAG bar of the SLAB type.
• Such a laser ensures propagation of the photons resulting from the emission stimulated by multiple reflections inside the cavity. This avoids on the one hand the thermal effects and, on the other hand, produces a very little expanded beam.
• the yield obtained with an SLAB bar is approximately 10 times higher than that obtained with an ordinary YAG bar.
• This beam is single-phase with a cleaner phase front which gives, if the frequency is doubled, using a KDP crystal (double potassium and deuterium phosphate) or, preferably, with a phosphate crystal triple known in the art under the name of KTP, a green laser beam, very clean, the frequency of which can again be doubled to obtain with better efficiency an ultraviolet radiation suitable for carrying out photoablation.
• a second YAG bar serving as an amplifier for the first, an assembly which made it possible to obtain an output of the order of 5 joules at the output of the second bar.
• the device uses at least one phase conjugation mirror making it possible to clean the beam without changing the wavelength thereof.
• a device for implementing the invention in a first embodiment using a YAG laser
• _ Fig. 2 a diagram showing the device for implementing the invention with at least one YAG laser
• a fourth assembly including a phosphate laser
• the device comprises a source laser 1, excimer argon fluorite, enclosed in a casing 8 resting on the ground by a support (not shown) or mounted on an optical bench.
• an electrically controlled shutter 2 At the output of the laser 1 is mounted an electrically controlled shutter 2, the "curtain” of which is constituted by a glass slide “SCHOTT KG3", for example, controlled by a trip pedal 14 or even by a voice-controlled computer.
• the laser beam 10 After crossing the shutter, the laser beam 10 is directed onto the entry of an articulated arm 7 provided with a set of reflecting mirrors 9 adapted to the wavelength of the excimer.
• a set of reflecting mirrors 9 adapted to the wavelength of the excimer.
• the casing 8 are mounted cooling devices (not shown) allowing the laser and the various components of the system to work at an adequate temperature. According to the invention, the beam 10 is not concentrated during its transfer to the operating head.
• the beam 10 arrives at the outlet of the arm 7 on a convergence device 13, included in the operating microscope 3 (or in a slit lamp) which focuses the beam 10 at a point 12.
• the device also includes inside the casing 8 a Pockels cell (not shown) intended to ensure the blocking of modes.
• the lenses constituting the convergence system 13 are calcium fluoride (CaF2) or "SPECTROSIL B" lenses, bodies which are transparent for the wavelength of 193 nanometers emitted by the laser. 1.
• the beam 10 then has the shape of a line ten to two hundred microns wide by three to four millimeters long.
• a beam transducer or deflector 4, disposed in the vicinity of the line 12 is constituted either by an acousto-optical modulator with Brague fringes in the event of temporal distribution of the beam, or by a set of mirrors in the event of spatial distribution of the beam .
• the command is obtained by a microprocessor 5 programmed as a function of the configuration of the corneal incisions which it is desired to obtain.
• an alignment laser 6 for example of the Helium-neon type with a power of 1 milli att, for example allowing to operate with precision and to arrange the incisions on the cornea, since, obviously, the UV beam is not visible.
• the laser 6 emits through a focal lens a continuous ray 11 which is superimposed on the ray 10 of the laser 1.
• the excimer laser 1 delivers pulses of 10 to 30 nanoseconds. From a slit adjustable from 4mm high by 0.1 to 0.2mm wide or less (for example from 10 to 200 microns), each line of incision is scanned in 30 nanoseconds.
• the surgeon's eye 01 observes the patient's eye 02 through the microscope 3, preferably through a protective plate (not referenced). With the EXCIMER laser, cell 27 does not exist.
• the excimer lasers make it possible to carry out photoablation by photodissociation of the material without there being, at the periphery of the vaporized zone, too marked deterioration by thermal effect.
• the incident energy diffuses little and is mainly used to locally cut the material.
• the beam of these lasers is not clean, that is to say that it is of a highly random geometry, it is not pure, it is multimode, and difficult to focus.
• gas lasers are difficult to mass produce, and pose safety problems in the event of leaks, especially when the gas used is a compound as active as fluorine, although precautions are taken by the automatic regeneration of gas and stabilization measures to avoid frequent recharging despite repeated work.
• the laser source is advantageously a solid-state laser. But there are no solid lasers emitting in a length wave suitable and with a power suitable for corneal surgery.
• the laser source 1 can then be a YAG source, advantageously of the SLAB type, the assembly diagram being that shown in FIG. 1 and which corresponds to that described in EP-A-0 007 256, with the exception of scanning. final spatiotemporal.
• the nature of the mirrors is adapted to the wavelength of the YAG radiation.
• the only difference in the assembly consists in the interposition before or after the scanning of a cell 27 of sodium borate which transforms the wavelength of the beam from 1064 nm to 200-210 nm, that is to say say a practically ideal wavelength for corneal surgery.
• Figs 2 to 4 show mounting methods for obtaining laser radiation for the previously defined wavelength range (150 - 215 nm) from a bar laser source. In these diagrams, only the main elements and the shutters, the cooling devices and the Pockels cell ensuring active Q-s itching have been deliberately omitted.
• Fig. 2 shows a second arrangement in which the original beam is emitted by a YAG laser whose wavelength (1064 nm) is much greater than the wavelength of the ultraviolet laser used in the first embodiment .
• the device comprises, in this case, a first laser YAG 1 (double garnet of aluminum and of Yttrium doped with neodymium) followed by a second laser YAG 21, amplifier connected in series with the first.
• a first laser YAG 1 double garnet of aluminum and of Yttrium doped with neodymium
• a second laser YAG 21, amplifier connected in series with the first.
• the YAG beam is pulsed at a frequency such that the duration of the pulses is between 10 and 100 nanoseconds.
• the power required for the output must always be between 0.1 and 1 Joule for the desired biophysical result.
• the device comprises: an electrically controlled shutter composed of a glass slide Schott KG3, an optical system called afocal making it possible to adjust the convergence of the alignment beam and the main beam so that the two beams coincide in the operating area and a Pockels cell ensuring active Q-switching.
• a first cell 22 of KDP or KTP double or triple phosphate of deuterium and potassium
• KDP or KTP double or triple phosphate of deuterium and potassium
• this result can be obtained, as shown in Fig.2, by having two frequency doublers in series, the first 22 of which selects the first harmonic and the second 23 selects of the third harmonic.
• the excess of the light of the beam 10 (1064 nm) is mixed by the link 25 with the third harmonic in a RAMAN tank 24 whose output delivers a radiation of wavelength equal to 217 nm, and a maximum energy of 800 mJ / cm2.
• the device is mounted on an operating microscope via an articulated arm and contains a beam deflector similar to that which was described in the previous embodiment for the fluoride excimer laser d 'argon. It is thus possible to obtain a device producing ultraviolet laser radiation from one or two YAG lasers, the aim of this device being to avoid heavy maintenance, to reduce the cost of assembly and to avoid the insecurities due fluorine leakage and the instabilities inherent in the excimer laser. It is thus possible to obtain in the short ultraviolet a laser beam of better quality than that of the excimer.
• the device shown in Fig.3 uses a single ruby laser 1 pulsed in nanoseconds whose wavelength is 694 nanometers.
• the active medium consists of an alumina crystal (A1203) doped with 0.05% chromium ions.
• A1203 alumina crystal
• chromium ions such as a laser makes it possible to obtain a gain equal to two to four times the gain of a YAG laser, which avoids the use of an amplifier laser. But this wavelength is too large to be used as it is in corneal surgery.
• the KDP crystals are replaced by crystals of ADP (double phosphate of ammonium and deuterium) or of KTP .
• a first harmonic of wavelength equal to 347 nm is thus obtained, which cannot be used because it is too penetrating and a second harmonic whose wavelength is 175.5 nm. whose wavelength falls within the useful radiation range for corneal surgery.
• the ruby laser 1 delivers a power of around 20 Joules at the outlet and is followed by two doublers
• the output beam of the doubler 22 is directed onto a slot followed by an electroacoustic or even purely optical beam deflector.
• the power at the output of the second doubler selecting the third harmonic can vary from approximately 5 to 10 Joules.
• a fourth device uses a phosphate laser source emitting radiation whose wavelength is 1054 nm.
• the original beam is processed to separate the third harmonic therefrom, on slides 22, 23 in ADP, KDP or KTP, the wavelengths being as follows: 1st harmonic 527 nm; 2nd harmonic 263.5 nm and third harmonic 131.7 nm.
• the wavelength of the third harmonic is too small for it to be used directly (absorption by air).
• a RAMAN tank 24 on which the third harmonic and a deviated part 25 of the original beam are simultaneously applied, so as to cause a frequency beat.
• the first antistoke frequency radiated along a cone focused on the main beam is established at 193 nm. or the wavelength of the argon fluoride excimer laser.
• the blades of ADP or KDP or of sodium borate crystal are mounted articulated on a support so as to be removable and out of the beam path.
• a multiplicity of ophthalmological operations using laser beams of different wavelengths.
• Fig. 5a shows a first example of a radial incision of the cornea C obtained using the method according to the invention.
• the cut lines T are arranged radially so as to allow a correction of the convexity of the cornea.
• Sure Fig. ⁇ b shows a second mode of photoablation incision, the T incision lines being arranged in an octagon, it was found that this arrangement practically eliminated postoperative astig atisms in keratoplasties.
• These configurations, as well as all the other desirable configurations are obtained by deflecting the beam 10 which is distributed into a plurality of secondary beams either by means of an acousto-optical transducer, or by means of a set of mirrors.
• FIG 6 there is a solid laser source 1 which emits a beam oriented towards a first doubler stage 22 of KTP.
• the beam used at the output of stage 22 has a frequency doubled compared to the frequency emitted by the laser 1 and consequently emits substantially in the green.
• Part of the energy of this output beam is taken by the optical path 25 and then applied to the stage 24, at the output thereof.
• This sample is intended to constitute the aiming beam.
• the cell 22 is followed by a second cell 23 advantageously constituted by a KTP crystal.
• the beam, after passing through the doubling cell 23, is then routed on the stage 24 allowing a distribution, either spatial or temporal, of the beam.
• the mirror 26 is arranged directly at the outlet of the laser cavity 1, and it is the beam thus purified which is directed on the doubling cells 22 and 23.
• the conjugate mirror 26 can be placed anywhere in the path of the beam and, for example, as in FIG. 7, at the exit from stage 23 or on the distribution stage 24 of the beam, before the division of this one or at the entrance to floor 24.
• FIGS. 6 and 7 represent an assembly with a solid laser (for example with a ruby) emitting a radiation of wavelength equal to 694 nanometers, including the quadrupling of the frequency for a KTP cell (22) gives a second harmonic of wavelength equal to 173.5 nanometers.
• a 3rd harmonic is mixed with part of the beam taken at the output of laser 1 in a RAMAN tank.
• the device is mounted on an ultrasound pachymeter for measuring the thickness of the cornea.
• a computer makes it possible to know the depth of the incision and a stop device immediately stops the operation of the source laser in the event of eye movement greater than four microns.
• the incision depth is currently around 1 micron per stroke, the laser being drawn at a rate of 2 to 100 Hertz.
• the depth of the tissue to be cut is, according to the operations, at most equal to approximately 600 microns.

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• Health & Medical Sciences (AREA)
• Ophthalmology & Optometry (AREA)
• Heart & Thoracic Surgery (AREA)
• Vascular Medicine (AREA)
• Optics & Photonics (AREA)
• Surgery (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Physics & Mathematics (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
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• Laser Surgery Devices (AREA)
• Radiation-Therapy Devices (AREA)

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• 1986
  • 1986-07-30 WO PCT/FR1986/000268 patent/WO1987000748A1/fr not_active Application Discontinuation
  • 1986-07-30 EP EP19860904836 patent/EP0232347A1/de not_active Withdrawn

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