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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
  • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
  • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
  • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
  • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
  • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
  • B23K26/0648—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms comprising lenses
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
  • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
  • B23K26/064—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
  • B23K26/0652—Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms comprising prisms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/02—Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
  • B23K26/06—Shaping the laser beam, e.g. by masks or multi-focusing
  • B23K26/0665—Shaping the laser beam, e.g. by masks or multi-focusing by beam condensation on the workpiece, e.g. for focusing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/08—Devices involving relative movement between laser beam and workpiece
  • B23K26/10—Devices involving relative movement between laser beam and workpiece using a fixed support, i.e. involving moving the laser beam
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
  • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
  • B23K26/14—Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beam; Nozzles therefor
  • B23K26/146—Working by laser beam, e.g. welding, cutting or boring using a fluid stream, e.g. a jet of gas, in conjunction with the laser beam; Nozzles therefor the fluid stream containing a liquid
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
  • A61B18/18—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves
  • A61B18/20—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser
  • A61B18/22—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor
  • A61B18/26—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor for producing a shock wave, e.g. laser lithotripsy
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
  • A61B18/18—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves
  • A61B18/20—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser
  • A61B2018/206—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using laser the laser light passing along a liquid-filled conduit
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
  • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
  • A61C1/0046—Dental lasers
• • 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
  • A61F2009/00863—Retina
• • 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
  • A61F2009/0087—Lens
• • 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
  • A61F2009/00885—Methods or devices for eye surgery using laser for treating a particular disease
  • A61F2009/00887—Cataract

Definitions

• This invention relates to method and apparatus for effecting surgery through the application of a laser beam.
• the present method and apparatus are particularly applicable to the delivery of laser energy for performing various surgical procedures. These include eye surgery, and more particularly cornea, cataract or vitreai surgery, and various dental procedures.
• the laser must be delivered in high powered pulses or with high continuous power
• the laser must be tuned to the extreme infrared end of the spectrum where water, a major constituent of living tissue, is a strong absorber.
• Condition (a) functions through non-linear optical processes such as dielectric breakdown. See for example "Laser Induced Electric Breakdown in Solids" by N. Bloembergen, IEEE. J. of Quantum Electronics, Volume QE10 Number 3, March 1974, pages 375 to 386. The non-linear process creates a finely localized absorption site since the resulting plasma is usually opaque to the laser beam.
• a particular application of the present invention is in keratoplasty.
• keratoplasty techniques which depend on a deposition of heat energy, i.e., heat induced keratoplasty.
• the principle behind heat induced keratoplasty is that of producing shrinkage in the principal protein of the clear corneal medium, collagen.
• type I collagen is heated above 62° C, there is a break in the collagen cross links, and contraction of the collagen occurs. Collagen contraction, in turn, modifies the corneal curvature.
• Original approaches to heat delivery were dependent on direct contact of the corneal surface with a heater.
• the clear disadvantage of this technique is that unnecessary collateral heat damage of anterior layers of the cornea takes place.
• Another approach is by radio frequency radiation heating of the mid-stromal layer by means of an antenna-like probe, as described by J.D. Doss, et al U.S. Patent 4,326,529.
• the method of Doss et al involves heating the central stroma with a radio frequency electrode probe, at the same time cooling the surface of the cornea with a saline solution.
• a clear disadvantage of this approach is that the heat deposition is not easily localized in the three-dimensional space of the cornea, because of the use of the radio frequency wavelengths required by this method. The application of radio frequency radiation resulted in an insufficiently localized distribution of the heat energy.
• Another application of the present invention is in cataract surgery.
• the lens is removed by suction, after having been emulsified by an ultrasonic probe, known as a phacoemulsifier.
• the ultrasonic energy causes fragmentation of the human lens nucleus, so that it could then be aspirated through fine tubing and thereby removed from the eye.
• This method of cataract surgery which is at present the prominent method used in the United States. These limitations include the possibility that the high ultrasonic frequency fragmentation may result in the fragmentation of the nucleus of the lens in large multiple pieces, thereby complicating the actual handling and separation of the cortex.
• vitreous infusion suction cutter is basically comprised of various scissor-like cutting devices which are combined with a suction element for the removal of fragments in the vitreous.
• a probe having a lens system which includes first and second lenses remote from the distal end of the probe, and which serve to receive a relatively large diameter beam of collimated light and to reduce it to a smaller diameter beam of collimated light: a lens at the distal end or tip of the probe has either two planar surfaces, or an external planar surface and an internal curved surface which focus the beam on the window outer surface.
• the probes disclosed are equipped to provide for an endoscope, to view the site, and fluid passage for fluid flow through the probe.
• Choi 4,207,874 discloses an apparatus using a laser beam, conducted through a fiberoptic bundle to a thrombus to burn a tunnel through the thrombus.
• Muncheryan 3,382,343 and Muncheryan 3,383,491 teach laser beam apparatus with optical systems for focussing the laser beam on a workpiece:. the lens position in this apparatus is fixed so that the plane of the laser beam coincides with the surface of the workpiece in contact with the instrument tip.
• a laser beam instrument in which there is a movable lens element, to permit displacement of the focal plane to any desired distance remote from the tip of the probe, so as to provide a cutting operation on body tissue, for example, with the tip of the probe remote from the body to avoid contamination.
• Goldenberg 4,641,912 discloses a system for delivering an excimer laser beam for angioplasty, including an optical fiber with the distal end formed as a lens to increase the density of the energy after it has emerged from the fiber by reducing its cross- section: in use, the end of the fiber is positioned at a distance from the obstructing lesion, so that the focal plane is at the surface thereof.
• Hett 4,072,147 is another example of a laser beam focussed on an object for therapeutic purposes.
• Laser energy of predetermined characteristics is focussed to a focus spot having a diameter of a few microns which is located a predetermined distance, - such as one millimeter, beyond a lens at the distal end of a handpiece, the focus spot being located, for example, in the intrastromal layer.
• the lens at the distal end of the handpiece, of sapphire is placed against the cornea, and localized heating in the instrastromal layer modifies the corneal curvature to effect keratoplasty or keratotomy.
• Laser energy is delivered in the TEM(oo) mode, the laser beam having a wavelength of approximately 1.0 to 2.0 microns, and in one embodiment a repetitively Q-switched YAG laser emits at 1064 nanometer wavelength.
• the pulses have a duration of about 70 nanoseconds, and pulsing is at the rate of approximately 2000 per second.
• continuous radiation having a wavelength in the range of 1400-1800 nanometers is generated by using a Neodymium YAG laser to pump f-centers in sodium chloride crystals, or a YAG laser is used to stimulate Raman scattering in a hydrogen gas cell which emits at 1900 nanometers.
• the handpiece contains an optical wedge which is oscillated or rotated in order to oscillate or rotate the focus spot while the handpiece is stationary.
• a focussing lens of a handpiece is spaced from the distal end, the end portion of the handpiece narrowing or tapering towards the distal end, there being a fluid inlet into the terminal portion of the handpiece, with fluid flowing in the tapering terminal portion and exiting through escape channels at the distal end, the laser beam travelling through fluid flowing through the handpiece terminal portion.
• the terminal portion of a handpiece is provided with a contact tip of glass, light being delivered to the penetration point through a single mode optical fiber and the contact tip, and an optical fiber bundle receiving an image of the penetration point from a reflective surface of the contact tip for passage of it to a display.
• the contact tip is provided with escape channels at its distal end for the escape of saline solution passed through the terminal portion of the handpiece.
• a probe In embodiments used for conducting cataract or vitreal surgery in which photoablative laser radiation is used, a probe has a quartz rod to which the radiation is coupled, the probe containing an infusion passage and an aspirating passage on either side of the beveled distal end surface of the quartz rod, water flowing across the beveled distal end surface of the quartz rod from the infusion passage to the aspirating passage.
• a method and apparatus for the performance of surgical procedures by the delivery of high powered laser radiation in the fundamental transverse mode to highly localized focus sites within tissue, such as in the mid-corneal stroma, by application of a focus spot of a few micron diameter.
• Another object is to provide such a method and apparatus in which portions of the tissue adjacent to the focus spot are relatively undisturbed.
• Yet another object is to provide a method and apparatus for the localized delivery of short pulse photo-ablative laser energy to a diffraction limited spot size on dental sites.
• Another object is the provision of a handpiece for the delivery of laser energy, together with means for obtaining an image, of the .site.
• Another object of the invention is to provide a method and apparatus for delivering laser energy in localized sites using either pulsed or continuous radiation having a near infrared wavelength of 1.0- 2.0 microns, or an ultraviolet wavelength of about 190 - 300 nanometers.
• Still another object of the invention is to provide a laser apparatus and method characterized by the delivery of high power laser radiation to a highly localized site within tissue, and with movement of the focus spot without movement of the handpiece.
• Still another object is to provide an apparatus for delivering laser energy which includes the provision of fluid flow to remove debris caused by the application of the laser energy.
• Yet another object of the invention is to provide apparatus useful in cataract or vitreal surgery in which laser energy is delivered through a probe containing a quartz rod, with provision for infusion and aspiration of fluent material.
• FIG. 1 is a perspective view showing a handpiece in accordance with the present invention.
• Fig. 2 is a longitudinal cross-sectional view of the handpiece of Fig. 1 engaging a cornea.
• Fig. 3 is an enlarged view of the portions of Fig. 2 within circle 3 of Fig. 2.
• Fig. 4 is a chart showing results achievable with the method and apparatus of the present invention.
• Fig. 5 is a diagrammatic view of a laser system used in one embodiment of the present invention.
• Fig. 6 is a schematic view of another embodiment of a laser system used in and forming a part of the present invention.
• Fig. 7 is a view similar to Fig. 1 of a modification of the handpiece of Fig. 2.
• Fig. 7a is an enlarged view of the structure within circle 7a of Fig. 7.
• Fig. 8 is a diagrammatic view illustrating the operation of the handpiece of Fig. 7.
• Fig. 9 is a longitudinal cross-sectional view of a modified handpiece terminal portion, and schematic representations of other sources for generating photo ⁇ ablative laser radiation.
• Fig. 10 is a perspective view of the distal end of the terminal portion of Fig. 9.
• Fig. 11 is an elevational view, with parts in section, of the terminal portion of a laser handpiece and endoscope.
• Fig. 12 is a cross-sectional view taken on line 12-12 of Fig. 11.
• Fig. 13 is a view taken on line 13-13 of Fig. 11.
• Fig. 14 is a longitudinal cross-sectional view of a photoablative terminal probe for cataract surgery.
• Fig. 15 is a view taken on line 15-15 of Fig. 14.
• Fig. 16 is a cross-sectional view taken on line
• Fig. 17 is a longitudinal cross-sectional view of an alternate embodiment of a photoablative probe for vitreal surgery.
• Fig. 18 is an end view of the probe of Fig. 17.
• Fig. 19 shows probes in accordance with Figs. 14 and 17 in use.
• the handpiece 20 is shown being applied to the eye E of a patient.
• Handpiece 20 depends from a support block 22 having a prism 23 therein for refracting light originating from laser source S.
• the handpiece 20 includes an outer tube 24 rotatably mounted on an inner tube 26 which is connected to the support block 22.
• a plano ⁇ convex focussing lens 27 At the lower end of tube 24 of handpiece 20, there is a plano ⁇ convex focussing lens 27. Beyond lens 27, there is a terminal portion 28 of smaller diameter, within which is a second lens 29, lens 29 also being a plano-convex lens.
• the lens 27 is 6.3 mm diameter with a 30.7 mm focal length, and is positioned 23 to 26 mm from the lens 29.
• Lens 29 is a sapphire lens 1.5 mm in diameter and having a 1.0 mm focal length.
• laser beam LB is reflected by prism 23 along the axis of the handpiece 20, and is focussed by the objective lenses 27 and 29, passing through air along its path until it exits from the lens 29.
• Lens 29 is held with the piano surface 31 thereof against the cornea C of the patient.
• the residual fluid of the corneal surface optically couples lens 29 to cornea C.
• the laser beam radiation is in TEM(oo) mode and is diffraction limited: it is focussed as a focus spot FS, shown rotated 90° from its normal position for purposes of clarity, the focus spot FS being of minimum size, of a few, i.e., 3-5 microns diameter.
• the focus spot FS lies at a predetermined distance into the cornea from the outer surface thereof, as determined by the focal lengths of lenses 27 and 29, which, in a preferred embodiment provided, is one millimeter.
• the focus spot FS is within the cornea C about 0.4 - 0.5 millimeter from the surface thereof.
• the laser source S is a repetitively Q- switched CW lamp pumped Neodymium YAG laser, such as the Quantronics Model 117.
• the pulses are at a high pulse rate of about 2000 per second, and have a duration of about 70 nanoseconds or less.
• This source emits a laser beam having a wavelength of 1064 nanometer.
• the induced plasma shields the posterior layers of the cornea C, and deposits highly localized energy to the stromal fibers. This results in a cutting process.
• the handpiece 20 may be used for intrastromal keratomeleusis for the purpose of effecting and correcting myopia or myopic astigmatism.
• the handpiece 20 can be freely passed along and over the surface of the cornea C, so as to achieve a desired pattern of treatment loci.
• Fig. 4 is a schematic diagram showing the temperature at various depths in the cornea due to different methods of application of energy.
• Line A shows the temperature distribution when a heated element is applied to the surface of the cornea, there being a temperature of approximately 75° C at the surface of the cornea, the temperature dropping to approximately 40° C at the endothelium layer.
• the temperature distribution is shown by line B; there is significant heating of Bowman's membrane and Descement's membrane.
• the more finely localized line C shows the energy distribution achieved with the present invention apparatus and method.
• the significant heating is confined to the central stroma, without undesirable heating of adjacent membranes. Referring to Figs.
• sources S-2 and S-3 of laser beams These emit preferably a diffraction limited beam with a wavelength in the range of 1400 to 1800 nanometers.
• the beam can be continuous, rather than pulsed as is the case with source S. This is possible because the radiation would be attenuated by a factor of 100 after travelling through only about one millimeter of the corneal or other tissue, due to water absorption. Since the absorption is linear and the energy deposited per unit volume varies as the reciprocal of the cubic power of the distance traversed into the corneal media, the linear energy deposition per unit volume, hence temperature, rises very sharply at the focus site. Thus, the melting process can be affected at the focus point, modifying the stromal tissue fibers in the desired localized manner, and without disturbing adjacent portions of the cornea.
• a laser beam LB is generated by a Neodymium YAG laser 32, the laser beam LB having a wavelength of 1064 nanometers.
• the laser beam LB passes through a lens 33 and strikes a sodium chloride crystal 34 having f-centers, which are pumped in conventional manner, the resulting beam L3' being a tuneable near infrared beam having a wavelength range of 1400 to 1800 nanometers.
• the source S-3 includes the Neodymium YAG laser 32, the laser beam LB of which passes through a focussing lens 36 and into a pressurized hydrogen gas cell 37.
• the laser beam causes stimulated Raman scattering in the pressurized hydrogen gas cell 37 so that the incoming laser beam LB is Raman shifted from 1064 nanometer wavelength to 1900 nanometer.
• the sources S-2 and S-3 may be used instead of the source S, shown in Fig. 1, to provide continuous as well as a pulsed, laser beam application to the cornea, shifted toward the absorption bands in water.
• the apparatus and method are not limited to treatment of corneas, but may be used for other general surgical purposes.
• Fig. 7 discloses an alternate embodiment of a handpiece 40 for laser surgery, having, as in the handpiece 20, an outer tube 24 rotatably supported by an inner tube 26, with a terminal portion 28 having at the distal end thereof a lens 29 preceded by lens 27.
• An optical wedge 41 is rotatably supported in the tube 24, and caused to rotate or oscillate by any suitable apparatus.
• a miniature motor 42 which drives through gears 43a and 43b a shaft 44, on the lower end of which is a gear 45.
• the optical wedge 41 may be supported in an annular holder 46, having an annular gear 47 thereon which is in mesh with the drive gear 45 through an opening 49 in tube 24.
• the carrier 46 is rotatably supported by ball bearings 48 which engage the interior wall of the tube 24.
• Fig. 8 there is shown the laser beam LB refracted by the plano-convex sapphire objective lens 29, to focus the laser beam L3 at the focus spot FS which is within the cornea C. Due to the oscillatory or rotational movement of the optical wedge 41, the focus spot FS will move relative to the axis of handpiece 40 while the handpiece 40 is held stationary. Thus, the focus spot FS will move in an arc of a circle, or in a complete circular path, due to the oscillatory or rotary movement of optical wedge 41. Motion of the focus spot FS at the target site over loci in very close proximity causes a marked reduction of the plasma induction threshold; this facilitates the cutting action and increases the energy localization many-fold.
• the handpiece 40 may also be used in the dental field, where the finely focussed and moving focus spot FS enables very hard tooth enamel to be cut without either charring the enamel or heat build-up. In either surgery or dental applications, the oscillatory movement of the focus spot FS so as to reach progressively further loci along the arc is an effective method for facilitating the cutting action.
• Fig. 9 is a view of an alternate terminal portion for a handpiece such as the handpiece 20, there being shown the outer tube 24 having a plano-convex lens 27 sealed in the distal end thereof.
• Objective lens 27 has a 30 mm focal length, and is of 4 mm diameter, in a preferred embodiment, providing a spot size of about ten to thirty microns.
• a terminal portion 50 of the handpiece has an enlarged cylinder 51 into which the end part of the outer tube 24 extends, cylinder 51 at its upper end being hermetically secured to the outer surface of outer tube 24.
• An inlet conduit 52 is connected to the cylinder 51 for the introduction of a fluid.
• Terminal portion 50 below the cylinder 51 has a tapered connecting portion 53 and below that is a conical portion 54. The distal end of tapered portion
• the laser beam LB is delivered form sources described below. Normal saline solution is introduced into the terminal portion 50 through the inlet conduit 52, and substantially fills it, as shown. The radiation, after passing through the lens
• Figs. 9 and 10 is particularly useful where a cutting is required, such as the making of radial keratotomy cuts for the purpose of effecting correction of myopia and myopic astigmatism, although the apparatus may be used in general surgical practice.
• the cutting action results from the photoablative property of the excimer laser pulses from source S-4, provided by excimer laser 55: these pulses have a wavelength of 248 nanometers for a krypton fluoride laser 55, 193 nanometers for an argon fluoride laser 55, and 308 nanometers for an Xenon chloride laser 55.
• these lasers provide far UV excimer laser radiation in the TEM(oo) mode.
• a source S-5 may be utilized, comprising a Q-switched/mode-locked Neodymium YAG laser 56, which generates, as above noted, a laser beam having a wavelength of 1064 nanometers.
• the crystal 57 is preferably potassium titanium phosphate.
• the radiation from the crystal 57 is delivered to a second crystal 58, where it is doubled, the crystal 58 being a fourth harmonic crystal, and may be beta barium borate.
• the resulting ultraviolet wavelength is at 266 nanometers.
• the radiation from the source S-5 will be recognized as being TEM(oo) ultraviolet radiation which has been up- converted by successive doubling caused by the second and fourth harmonic crystals 57 and 58, respectively.
• a terminal portion 60 which includes a tapered portion 64, shown filled with a liquid such as a normal saline solution, and having a laser beam LB passing axially thereof, focussing beyond the distal end and in a cornea C.
• the lower end of the tapered portion 64 is inserted into a socket formed by sleeve 66 (see also Fig. 12) of a glass contact tip 65.
• the sleeve 66 extends upwardly from, a solid internally reflective conical glass element 67 having internal reflection at surface 68.
• the distal end of the conical element 67 is provided, as shown in Fig. 13, with channels 69 for the escape of the saline solution.
• a single multimode fiber 71 adjacent tube 64 receives illumination from a light source 72, the light being transmitted into the glass contact tip 65 and illuminating the penetration point P of the ablative laser radiation provided by laser beam LB.
• the image # -r of the penetration point P is transmitted to the reflecting surface 68, and thence through the coupling lens 62 to a fine coherent fiberoptic bundle 63.
• the fiberoptic bundle 63 conveys the image to any receiver R desired, such as to monitoring and display elements and penetration control components (not shown).
• the inner core or passage 73 of the contact tip 65 is filled with fluid, such as the normal saline solution, index matching occurs at the interfaces and an image of the penetration point P is readily obtained by the contact tip 65, coupling lens 62 and fiberoptic bundle 63.
• a terminal portion 80 forming a probe useful for conducting ophthalmic intraocular, in particular, cataract surgery.
• the terminal portion 80 replaces the terminal portion of the handpiece 20 beyond the lens 27.
• the quarts rod 82 conveys the laser radiation by means of total internal reflection to the beveled end surface 83, where the radiation leaves the instrument and is sharply defined into a circular or semi-circular radiation distribution area A (shown rotated for clarity).
• the quartz rod 82 is housed within a generally elliptical tube 84 which is preferably a tight sealing rubber silicon sheath having an inlet conduit 85 connection to an internal passage 86 lying between the wall of the tube 84 and the quartz rod 82, the outlet end of passage 86 having a shape defined by two curved walls, as shown in Fig. 15.
• a discharge tube 87 is inserted part way into the tube 84 from the distal end thereof, to define the discharge port of the passage 86.
• an aspiration passage 88 having an aspiration conduit 89 connected to its end opposite the distal end, there being provided at the distal end of aspiration passage 88 a tubular extension 91.
• the ends of the discharge tube 87 and the tubular extension 91 are beveled, and lie in the same plane as the beveled end surface 83 of quartz rod 82.
• the relative locations of the passage 86, beveled and surface 83 and the entry port of aspiration passage 88 are shown in Fig. 16.
• the beveled end surface 83 causes the radiation distribution area A to lie displaced from the geometric axis of quartz rod 82 and at or towards the geometric axis of the passage 88. Tissue fragments TF which are drawn towards the aspiration passage 88 are subjected to the energy in radiation distribution area A, and are cut by the ablative radiation. Saline solution which enters the passage 86 is discharged adjacent to and flows across the beveled end surface 83 toward the entry port of aspiration passage 88, to remove debris.
• Fig. 17 discloses an alternate embodiment of probe, in which the silicon tube or sheath 94 has the quartz rod 82 in it, with, as shown in Fig. 18, the longitudinal axis of the cylindrical quartz rod 82 and the major longitudinal axis of elliptical sheath 94 coinciding. There are thereby provided an infusion passage 96, and an aspiration passage 98 in the equal- area spaces between the quartz rod 82 and sheath 94.
• the sheath 94 has the distal end thereof beveled, as shown in Fig. 17, and the end face 83 of quartz rod 82 lies in the plane of the beveled end of sheath 94.
• the longer end portion 97 of sheath 94 which forms the entrance to the aspiration passage 98 may have other shapes than as shown in Fig. 17, i.e. it may be angled as shown in Fig. 19.
• Fig. 19 shows the application of the tips of ⁇ Figs. 14 and 17 to cataract surgery and to vitreal strand removal or vitrectomy, respectively.
• cataract surgery there is inserted through the cornea
• Photoablative laser energy as above described, is delivered to the cataractous lens
• the terminal portion 95 of the probe shown in Figs. 17 and 18 is inserted through the pars plana and is used to cut vitreal strands VS.
• the end 97 of the sheath 94 is bent at an angle, as shown in Fig. 19, so as to enhance the lateral flow of vitreous strands across the radiation distribution area A of the cutting ablative radiation source which is emitted from the end surface of the quartz rod 82.

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• 1989
  • 1989-01-19 EP EP89902428A patent/EP0397777A1/en not_active Withdrawn
  • 1989-01-19 JP JP1502256A patent/JPH03502288A/ja active Pending
  • 1989-01-19 WO PCT/US1989/000156 patent/WO1989006519A2/en not_active Application Discontinuation
  • 1989-01-24 CA CA000589032A patent/CA1328486C/en not_active Expired - Fee Related
  • 1989-01-24 IL IL89059A patent/IL89059A0/xx unknown

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