Method and apparatus for facilitating removal of a corneal graft

Information

  • Patent Grant
  • 6425905
  • Patent Number
    6,425,905
  • Date Filed
    Wednesday, November 29, 2000
    24 years ago
  • Date Issued
    Tuesday, July 30, 2002
    22 years ago
Abstract
The invention relates to an artificial chamber that can support and pressurize a donor cornea to extract a corneal graft. The artificial chamber has a stationary stem that is adapted to support a cornea. The stem has an inner channel that allows air to pressurize the cornea. The artificial chamber has an outer cap that can be moved in a downward direction to secure the cornea. The cap has an opening that exposes a portion of the cornea to allow for the extraction of a corneal graft. The outer cap is attached to an outer sleeve that is moved by rotation of a cam. The chamber includes a spring that exerts a clamping force onto the cornea. The clamping force can be adjusted by rotating an adjustment wheel. The adjustable spring force allows an operator to set a desired clamping force that is then repeated for each grafting procedure.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to an artificial chamber that is used to support and pressurize a donor cornea to facilitate the removal of a corneal graft.




2. Background Information




There have been developed various techniques to correct the vision of a patient. For example, there is a medical procedure that varies the curvature of a cornea using a laser. This technique is commonly referred to as Las in situ Keratomileusis (LASIK).




A LASIK procedure is performed by initially cutting a flap in the cornea to expose the stroma layer of the eye. A laser beam is then directed onto the stroma to ablate corneal tissue. After ablation the flap is placed back onto the stroma. The result is a variation in the refractive characteristics of the eye.




The flap may become severed from the cornea either during or after the procedure. This may require obtaining another flap from a donor eye that must then be attached to the patient's cornea. To create a replicant corneal flap the donor corneal must be pressurized to create the proper radius of curvature. Therefore, to create a flap the donor cornea must not only be secured but also pressurized.




U.S. Pat. No. 6,045,563 issued to Duprat and assigned to Moria SA (“Moria”), discloses an artificial chamber that can be used to support and pressurize a cornea to extract a corneal graft. The Moria chamber includes a clamping cap that can be removed from a chamber stand to expose an internal stem. The donor cornea can be placed onto a pedestal portion of the internal stem. The clamping cap is then reattached to the stand.




An operator rotates a thumb wheel that moves the stem in an upward direction until the cornea engages the bottom surface of the clamping cap. The cornea is pressurized with air that flows through a center channel of the stem. A portion of the pressurized donor cornea extends through an opening in the clamping cap. A keratome can be attached to the cap and actuated to slice a graft from the cornea.




The Moria artificial chamber requires the operator to rotate the wheel until the cornea is secured to the clamping cap. This manual actuation may result in a deficient, or an excessive, clamping force on the cornea. It is desirable to have a clamping force that is the same for each procedure. The Moria patent discloses a second pneumatically actuated embodiment that would provide a repeatable clamping force, but the pressure required to move the stem may be less, or more, than the desired clamping force exerted onto the cornea. It would be desirable to provide an artificial chamber that can provide a repeatable desired clamping force on a cornea during a grafting procedure.




BRIEF SUMMARY OF THE INVENTION




One embodiment of the present invention is an artificial chamber that can be used to support and pressurize a cornea to extract a corneal graft. The artificial chamber may include a stem that is attached to a stand. The stem is adapted to support and pressurize a cornea. The chamber may further have an outer sleeve and a cap that can move relative to the stem. The sleeve and cap can be moved by an actuator to secure the cornea.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a cross-sectional view of an embodiment of an artificial chamber of the present invention;





FIG. 2

is a cross-sectional view similar to

FIG. 1

showing a cornea secured by the chamber.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




In general the present invention provides an artificial chamber that can support and pressurize a donor cornea to extract a corneal graft. The artificial chamber has a stationary stem that is adapted to support a cornea. The stem has an inner channel that allows air to pressurize the cornea. The artificial chamber has an outer cap that can be moved in a downward direction to secure the cornea. The cap has an opening that exposes a portion of the cornea to allow for the extraction of a corneal graft. The outer cap is attached to an outer sleeve that is moved by rotation of a cam. The chamber includes a spring that exerts a clamping force onto the cornea. The clamping force can be adjusted by rotating an adjustment wheel. The adjustable spring force allows an operator to set a desired clamping force that is then repeated for each grafting procedure.




Referring to the drawings more particularly by reference numbers,

FIG. 1

shows an embodiment of an artificial chamber


10


of the present invention. The artificial chamber


10


may include a stem


12


that is coupled to a stand


14


. The stem


12


is coupled in a manner to allow movement relative to the stand


14


. The stem


12


may have a countersunk opening


16


in a pedestal portion


17


. The countersink


16


and pedestal portion


17


are configured to support a cornea (not shown). The opening


16


may be in fluid communication with a center fluid channel


18


. The fluid channel


18


may be in fluid communication with inlet/outlet ports


20


and


22


. The inlet/outlet ports


20


and


22


are typically coupled to a source of pressurized air through a control valve (not shown). By way of example, the source of pressurized air may be an air line in a commercial building structure.




The artificial chamber


10


may further have an outer sleeve


24


that can move relative to the stem


12


. The stem


12


may have an outer upper bearing surface


26


to insure translational movement of the outer sleeve


24


. The outer sleeve


24


may include a slot


28


that receives an actuator


30


. The actuator


30


may include a threaded stem portion


32


that screws into a corresponding threaded aperture


34


of the stand


14


. The actuator


30


may also have a cam portion


36


that is off-center from the stem portion


32


so that rotation of the cam


36


moves the outer sleeve


24


in an up and down direction as indicated by the arrows.




An outer cap


38


is attached to the outer sleeve


24


. The cap


38


may have internal threads


40


that screw onto corresponding external threads


42


of the outer sleeve


24


. The cap


38


is adapted to engage and secure a donor cornea that is placed onto the pedestal portion


17


of the stem


12


. The cap


38


further has an opening


44


that allows a portion of the donor cornea to be exposed so that a graft can be extracted from the cornea. The cap


38


may have an external thread


45


that allows a keratome to be attached to the chamber


10


and actuated to create the corneal graft.




The chamber


10


may further have a spring


46


that exerts a spring force onto stem


12


. The spring force can be adjusted by rotating an adjustment wheel


48


that can vary the compression length of the spring


46


. The adjustment wheel


48


can be accessed through an opening


50


in the outer sleeve


24


. Rotating the wheel


48


varies the clamping force exerted by the cap


38


onto the cornea. The spring


46


and wheel


48


provide a mechanism to repeatedly provide a desired clamping force onto the cornea that is neither inadequate nor excessive.




In operation, the cap


38


is removed from the outer sleeve


24


and a cornea


52


is placed onto the pedestal portion


17


of the stem


12


. The cap


38


is then reattached to the outer sleeve


24


. As shown in

FIG. 2

, the actuator


30


is rotated to move the cap


38


down into the cornea


52


. Air is then introduced to the inner channel


18


to pressurize the cornea


52


. A portion of the cornea


52


will extend through the cap opening


44


. An external device such as a keratome (not shown) can be attached to the cap


38


and actuated to extract a graft from the cornea


52


. Once the graft is removed, the cornea


52


can be depressurized. The actuator


30


can then be rotated to move the cap


38


away from the donor cornea


52


, wherein the cap


38


can be detached from the outer sleeve


24


and the cornea


52


removed from the stem


12


to complete the procedure.




While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.



Claims
  • 1. An artificial chamber that can support a cornea to create a corneal graft, comprising:a stand; a stem attached to said stand, said stem having a pedestal portion adapted to support the cornea and an air channel that can be in fluid communication with the cornea; an outer sleeve; a cap attached to said outer sleeve; and, an actuator that can create relative movement between said outer sleeve and said cap, and said stem.
  • 2. The artificial chamber of claim 1, further comprising a spring that exerts a biasing force on said stem.
  • 3. The artificial chamber of claim 2, further comprising an adjustment wheel that is coupled to said spring.
  • 4. The artificial chamber of claim 1, wherein said actuator includes a cam.
  • 5. The artificial chamber of claim 1, wherein said cap has an opening.
  • 6. The artificial chamber of claim 3, wherein said outer sleeve has an opening that provides access to said adjustment wheel.
  • 7. An artificial chamber that can support a cornea to create a corneal graft, comprising:a stand; a stem attached to said stand, said stem having a pedestal portion adapted to support the cornea and an air channel that can be in fluid communication with the cornea; an outer sleeve that can move relative to said stem; a cap attached to said outer sleeve, said cap having an opening that can expose a portion of the cornea; a spring that exerts a biasing force on said stem; and, a cam that can be rotated to move said cap into the cornea.
  • 8. The artificial chamber of claim 7, further comprising an adjustment wheel that is coupled to said spring.
  • 9. The artificial chamber of claim 8, wherein said outer sleeve has an opening that provides access to said adjustment wheel.
  • 10. A method for removing a corneal graft from a cornea, comprising:placing the cornea on a stem; actuating an actuator to move an outer sleeve and a cap relative to the stem until the cap engages and secures the cornea; pressurizing the cornea; and, removing a corneal graft from the cornea.
  • 11. The method of claim 10, wherein the outer sleeve and the cap are moved by rotating a cam.
  • 12. The method of claim 10, further comprising moving the cap away from the cornea and removing the cornea from the stem.
  • 13. The method of claim 10, further comprising adjusting a spring force that is exerted by the stem onto the cornea.
  • 14. The method of claim 13, wherein the spring force is adjusted by rotating an adjustment wheel.
US Referenced Citations (202)
Number Name Date Kind
1841968 Lowry Jan 1932 A
1847658 Lasker Mar 1932 A
2070281 Leggiadro Feb 1937 A
2480737 Jayle Aug 1949 A
RE23496 Seeler May 1952 E
2708437 Hutchins May 1955 A
2824455 Ristow et al. Feb 1958 A
3033196 Hay May 1962 A
3252623 Corbin et al. May 1966 A
3266494 Brownrigg et al. Aug 1966 A
3308828 Pippin Mar 1967 A
3399677 Gould et al. Sep 1968 A
3511162 Truhan May 1970 A
3561429 Jewett Feb 1971 A
3583403 Pohl Jun 1971 A
3589363 Banko Jun 1971 A
3624821 Henderson Nov 1971 A
3693613 Kelman Sep 1972 A
3723030 Gelfand Mar 1973 A
3752161 Bent Aug 1973 A
3763862 Spieth Oct 1973 A
3812855 Banko May 1974 A
3815604 O'Malley et al. Jun 1974 A
3841799 Spinosa et al. Oct 1974 A
3842839 Malis et al. Oct 1974 A
3882872 Douvas et al. May 1975 A
3884238 O'Malley et al. May 1975 A
3899829 Storm et al. Aug 1975 A
3903881 Weigl Sep 1975 A
3913584 Walchle et al. Oct 1975 A
3920014 Banko Nov 1975 A
3930505 Wallach Jan 1976 A
3977425 Hayashida Aug 1976 A
3982539 Muriot Sep 1976 A
3983474 Kuipers Sep 1976 A
3986512 Walliser Oct 1976 A
4004590 Muriot Jan 1977 A
4011869 Seiler, Jr. Mar 1977 A
4034712 Duncan Jul 1977 A
4043342 Morrison, Jr. Aug 1977 A
4108182 Hartman et al. Aug 1978 A
4135515 Muriot Jan 1979 A
4137920 Bonnet Feb 1979 A
4168707 Douvas et al. Sep 1979 A
4173980 Curtin Nov 1979 A
4178707 Littlefield Dec 1979 A
4204328 Kutner May 1980 A
4205682 Crock et al. Jun 1980 A
4210146 Banko Jul 1980 A
4217993 Jess et al. Aug 1980 A
4223676 Wuchinich et al. Sep 1980 A
4245815 Willlis Jan 1981 A
4246902 Martinez Jan 1981 A
4274411 Dotson, Jr. Jun 1981 A
4301802 Poler Nov 1981 A
4304262 Icking Dec 1981 A
4308385 Goorden Dec 1981 A
4308835 Abbey Jan 1982 A
4314560 Helfgott et al. Feb 1982 A
4319899 Marsh Mar 1982 A
4320761 Haddad Mar 1982 A
4344784 Deckas et al. Aug 1982 A
4354838 Hoyer et al. Oct 1982 A
4395258 Wang et al. Jul 1983 A
4396386 Kurtz et al. Aug 1983 A
4427427 DeVecchi Jan 1984 A
4428748 Peyman et al. Jan 1984 A
4429696 Hanna Feb 1984 A
4445517 Feild May 1984 A
4474411 Peters et al. Oct 1984 A
4475904 Wang Oct 1984 A
4476862 Pao Oct 1984 A
4479717 Cornillault Oct 1984 A
4481948 Sole Nov 1984 A
4493695 Cook Jan 1985 A
4493698 Wang et al. Jan 1985 A
4522371 Fox et al. Jun 1985 A
4523911 Braetsch et al. Jun 1985 A
4524948 Hall Jun 1985 A
4530357 Pawloski et al. Jul 1985 A
4531934 Kossovsky et al. Jul 1985 A
4540406 Miles Sep 1985 A
4555645 Atkinson Nov 1985 A
4560395 Davis Dec 1985 A
4589414 Yoshida et al. May 1986 A
4598729 Naito et al. Jul 1986 A
4647209 Neukomm et al. Mar 1987 A
4660566 Swinger et al. Apr 1987 A
4660970 Ferrano Apr 1987 A
4662370 Hoffmann et al. May 1987 A
4665914 Tanne May 1987 A
4674499 Pao Jun 1987 A
4674503 Peyman et al. Jun 1987 A
4678459 Onik et al. Jul 1987 A
4688570 Kramer et al. Aug 1987 A
4690099 Gregan et al. Sep 1987 A
4701049 Beckmann et al. Oct 1987 A
4705395 Hageniers Nov 1987 A
4706687 Rogers Nov 1987 A
4723545 Nixon et al. Feb 1988 A
4743770 Lee May 1988 A
4757814 Wang et al. Jul 1988 A
4767403 Hodge Aug 1988 A
4768506 Parker et al. Sep 1988 A
4770654 Rogers et al. Sep 1988 A
4782239 Hirose et al. Nov 1988 A
4782849 Hodge Nov 1988 A
4791934 Brunnett Dec 1988 A
4805615 Carol Feb 1989 A
4805616 Pao Feb 1989 A
4807623 Lieberman Feb 1989 A
4819635 Shapiro Apr 1989 A
4825091 Breyer et al. Apr 1989 A
4828306 Blatt May 1989 A
4830047 Hodge May 1989 A
4837857 Scheller et al. Jun 1989 A
4838281 Rogers et al. Jun 1989 A
4840175 Peyman Jun 1989 A
4865033 Krumeich et al. Sep 1989 A
4884570 Krumeich et al. Dec 1989 A
4886085 Miller Dec 1989 A
4903695 Warner et al. Feb 1990 A
4909815 Meyer Mar 1990 A
RE33250 Cook Jul 1990 E
4943289 Goode et al. Jul 1990 A
4965417 Massie Oct 1990 A
4988347 Goode et al. Jan 1991 A
4997437 Grieshaber Mar 1991 A
5011482 Goode et al. Apr 1991 A
5013310 Goode et al. May 1991 A
5019076 Yamanashi et al. May 1991 A
5059204 Lawson et al. Oct 1991 A
5083558 Thomas et al. Jan 1992 A
5092874 Rogers Mar 1992 A
5106364 Hayafuji et al. Apr 1992 A
5133713 Huang et al. Jul 1992 A
5133726 Ruiz et al. Jul 1992 A
5176628 Charles et al. Jan 1993 A
5201749 Sachse et al. Apr 1993 A
5207683 Goode et al. May 1993 A
5215104 Steinert Jun 1993 A
5217459 Kamerling Jun 1993 A
5226910 Kajiyama et al. Jul 1993 A
5242404 Conley et al. Sep 1993 A
5271379 Phan et al. Dec 1993 A
5273406 Feygin Dec 1993 A
5273524 Fox et al. Dec 1993 A
5285795 Ryan et al. Feb 1994 A
5322505 Krause et al. Jun 1994 A
5330470 Hagen Jul 1994 A
5354268 Peterson et al. Oct 1994 A
5364395 West, Jr. Nov 1994 A
5374188 Frank et al. Dec 1994 A
5380280 Peterson Jan 1995 A
5383454 Bucholz Jan 1995 A
5395368 Ellman et al. Mar 1995 A
5403276 Schechter et al. Apr 1995 A
5403311 Abele et al. Apr 1995 A
5437678 Sorensen Aug 1995 A
5465633 Bernloehr Nov 1995 A
5474532 Steppe Dec 1995 A
5476448 Urich Dec 1995 A
5476473 Heckele Dec 1995 A
5496339 Koepnick Mar 1996 A
5507751 Goode et al. Apr 1996 A
5520684 Imran May 1996 A
5527332 Clement Jun 1996 A
5527356 Peyman et al. Jun 1996 A
5531744 Nardella et al. Jul 1996 A
5556397 Long et al. Sep 1996 A
5566681 Manwaring et al. Oct 1996 A
RE35421 Ruiz et al. Jan 1997 E
D377524 Lipp Jan 1997 S
5611799 Smith Mar 1997 A
5624394 Barnitz et al. Apr 1997 A
5643304 Schechter et al. Jul 1997 A
5693013 Geuder Dec 1997 A
5700240 Barwick, Jr. et al. Dec 1997 A
5704927 Gillette et al. Jan 1998 A
5738677 Colvard et al. Apr 1998 A
5779723 Schwind Jul 1998 A
5782849 Miller Jul 1998 A
5787760 Thorlakson Aug 1998 A
5795328 Barnitz et al. Aug 1998 A
5810857 Mackool Sep 1998 A
5814010 Ziegler Sep 1998 A
5817075 Giungo Oct 1998 A
5868728 Giungo et al. Feb 1999 A
5916330 Jacobson Jun 1999 A
5941250 Aramant et al. Aug 1999 A
5944731 Hanna Aug 1999 A
5957921 Mirhashemi et al. Sep 1999 A
5989272 Barron et al. Nov 1999 A
6013049 Rockley et al. Jan 2000 A
6019754 Kawesch Feb 2000 A
6045563 Duprat Apr 2000 A
6051009 Hellenkamp et al. Apr 2000 A
6059805 Sugimura et al. May 2000 A
6083236 Feingold Jul 2000 A
6086544 Hibner et al. Jul 2000 A
6132446 Hellenkamp et al. Oct 2000 A
6165189 Ziemer Dec 2000 A
Foreign Referenced Citations (3)
Number Date Country
25 47 185 Apr 1977 DE
1033 120 Sep 2000 EP
2 549 727 Jul 1963 FR
Non-Patent Literature Citations (24)
Entry
Steinway Instrument Company Inc., The Steinway/Barraquer in-Situ Microkeratome Set.
Brochure, Site TXR Systems, Site Mycrosurgical Systems, Inc., Horsham, Pennsyvania.
Marshall M. Parks, “Intracapsular Aspiration”article, pp. 59-74.
Van Oldenborgh, “Correction of late operative complications by means of a suction cutter”, Opthal. Soc. U.K. (1980), 100, 219, pp. 219-221.
Helfgott, M.D. “A System for Variable Aspiration of Material Dissected from the Posterior Chamber”, Ophthalmic Surgery, vol. 15, Jun. 1984, pp. 529-350.
Coopervision Brochure on Cavitron/Kelman Model 6500 E.I.S. and Model 7500 6 pages.
Surgical Design Brochure on “The Ocusystem”, 1 page.
Coopervision Brochure on “Cavitorn/Kelman Phaco-Emulsifier Aspirator Model 8001”, 2 pages.
Coopervision Brochure on Cavitron/Kelman Phaco-Emulsifier Aspirator Model 9001, 6 pages.
Greishaber of Switzerland Brochure on “MPC, The Membrane Peeler Cutter”, 5 pages.
Micro-Vit Vitrectomy System Product Brochure and Instruction Manual.
Storz Irrigation Aspiration System Product Brochure and Instruction Manual.
United Surgical Corporation Brochure on “Phacotron Plus”, one page.
Surgical Design Company Brochure on Keates Ultrasonic I/E Mini Probe by A. Banko, 2 pages.
Surgical Design Corporation Brochure on U.S., Phaco System, 1 page.
Coopervision Brochure on System VI, 1 page.
Murayama et al. “A Portable Air Driving Unit for Blood Pumps”, Japanese Journal of Artificial Organs, vol. 14, No. 3, pp. 1206-1209 (English Translation).
Scuderi, et al., French article entitled “La Chirurgie de la Cartaracte Congenitale”, pp. 174-185. (English translation).
Hayashi et al., Japanese Experience with Ventricular Assist Devices IBEE Engineering in Medicine and Biology Magazine Mar. 1986, pp. 30-36.
Grieshaber and Co. of Switzerland, “Sutherland Rotatable Intraocular Microscissors”, 2 pages.
JCERS and Tissue Removal Systems, Diskecter™ System, Rapid Tissue Removal System advertisement.
Charles and Wang, “A Linear Suction Control for the Vitreous Cutter (Ocutome)”, Arch. Ophthalmol. vol. 99, Sep. 1981, p. 1631.
Crosby, “On Control of Artificial Hearts”, pp. 89-114.
Mrava, Cardiac Engineering, vol. 3, pp. 31-68.