CA2364038A1

CA2364038A1 - A universal implant blank for modifying corneal curvature and methods of modifying corneal curvature therewith

Info

Publication number: CA2364038A1
Application number: CA002364038A
Authority: CA
Inventors: Gholam Peyman
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-03-02
Filing date: 2000-03-01
Publication date: 2000-09-08
Also published as: EP1159033A4; MXPA01008760A; EP1159033A1; CN1342095A; ES2280203T3; JP2002537912A; BR0008624A; JP4114036B2; WO2000051682A1; EP1159033B1; DE60032746D1; AU3713400A; ATE350099T1; EP1159033B8; HK1042258A1; DE60032746T2; US6063073A; AU778310B2

Abstract

A universally sized blank (18) made of organic or synthetic material that can be placed on an exposed inner surface of a live cornea and ablated with a laser beam (L) to be altered to a particular shape. The blank (18) can be disk-shaped, annularly-shaped with a through opening, or any other suitable shape. A flap-like portion of the live cornea is removed to expose an inner surface of the cornea, and the blank (18) is positioned on the exposed inner surface of the eye. A laser beam (L) is directed onto a portion of the exposed inner surface (e.g., exposed at the opening in the blank), a portion of the blank (18), or both, based on the type of ametropic condition (i.e., myopia, hyperopia or astigmatism) of the eye needing correction, so that the laser beam (L) ablates those portions of the inner surface and/or blank (18) and thus reshapes the inner surface, the blank (18), or both.

Description

wo oois~baz Pcriusoorosasa A ZJIJIVERSAL IMp'LANT BLANK FOR MODIFYING CORNEAL CURVATURE
AND METHODS OF MODIFYI1~TG CORNEAL CURVATURE THEREWTTfi This is a continuation-in-part application of U.S. Patent Application Serial 'No.
08/845,448 filed April 25, 1997, the entire contents of which is incorporated herein by reference.

Field of the Invention:
The present invention relates to a universal blank which is used to modify the curvature of a live cornea when implanted herein. The blank is made of synthetic or organic nnataial, and can be shaped to the appropriate configuration while supported on an exposed inner surface of the comes wo ooist6s2 Pcr~sooros2sa Description of the Related Art:
A normal emetropic eye includes a cornea, lens and retina. The cornea and lens of a nomnal eye cooperatively focus light entering the eye from a far point, i.e., infinity, onto the retina However an eye can have a disorder known as ametropia, which is the inability of the lens and cornea to focus the far point correctly on the retina. Typical types of ametropia are myopia, hypermetropia or hyperopia, and astigmatism.
A myopic eye has either an axial length that is longer than that of a normal emetropic cye, or a cornea or lens having a refractive power stronger than that of the cornea and lens of an emetropic eye. This stronger refractive power causes the far point to be projected in front of the retina.
Conversely, a hypermetropic or hyperopic eye has an axial length shorter than that of a normal emetropic eye, or a lens or cornea having a refractive power less than that of a lens and cornea of an emetropic eye. This lesser refractive power causes the far point to be focused in back of the retina.
An eye suffering from astigmatism has a defect in the lens or shape of the cornea.
Therefore, an astigmatic eye is incapable of sharply focusing images on the retina A common method of correcting myopia is to place a "minus" or concave lens in front of the eye in order to decrease the refractive power of the cornea and lens.
In a similar mamrer, hypermetropic or hyperopic conditions can be corrected to a certain degree by placing a "plus" or convex lens in front of the eye to increase the refractive power of the cornea and lens. Lenses having other shapes can be used to correct astigmatism. The concave, convex or other shaped lenses are typically configured in the form of glasses or contact lenses. This technique, which involves the placement of lenses in front of the eye, is known as photorefractive keratectomy.
Although photorefractive keratectomy can be used to correct vision in eyes suffervrg from low myopia up to 6 diopters, or in eyes suffering from hypermetropic, hyperopic or astigmatic conditions which are not very severe, that method is ineffective in correcting vision in eyes suffering from sever forms of amet~opia. For example, photorefractive keratectomy is less effective in correcting high myopia of 6 diopters or greater, and is also ineffective in wo oo~sit~ Pcr~usoorosisa cornecting severe astigmatism and severe forms of hypermetropia or hyperogia.
However, surgical techniques exist for correcting these more severe forms of ametropia to a certain degree. For example, in a technique known as myopic keratomileusis; a microkeratome is used to cut away a portion of the front of the live comes from the main section of the live cornea. The cut portion of the cornea is frozen and placed in a cryolathe where it is cut and reshaped. Altering the shape of the cut portion of the cornea changes the refractive power of this cut portion, which thus affects the location at which light entering the cut portion of the cornea is focused. The reshaped cut portion of the cornea is then reattached to the main portion of the live cornea. Hence, it is intended that the reshaped cornea will change the position at which the tight entering the eye through the cut portion is focused, so ~ ~pe~y ~g t ~ focused on the retina, thus remedying the ametropic condition.
The myopic keratomileusis technique is known to be effective in curing myopic conditions within a range of 6 to 18 diopters. However, the technique is impractical because it employs very complicated and time consuming freezing, cuttsng and thawing processes.
Furthermore, the technique is ineffective in correcting myopic conditions greater than 18 dlOptBrB.
Keratophakia is another known surgical technique for correcting sever ametropic conditions of the eye by altering the shape of the eye's cornea. In this technique an artificial organic or synthetic lens is implanted inside the cornea to thereby alter the shape of the cornea sad thus change its refiactive power. Accordingly, as with the myopic kera~omnileusis ~~que; it is desirable. that the shape of the cornea be altered to a degree allowing light entering the eye to be focused correctly on the retina.
However the keratophakia technique is impractical, comPlica~, and expensive ba;ause it requires manufacturing or cutting a special lens prior to its insertion into the cornea Hence, a surgeon is required to either maintain an assorrtnent of many differently shaped lenses, or alternatively, must have access to expensive equipment, such as a cyrolathe, which can be used to cut the lens prior to insertion into the cornea.
Surgical techniques involving the use of ultraviolet and shorter wavelength lasers to modify the shape of the cornea also are known. For example, excimer lasers, such as those described in U.S. Patent No. 4,840,175 to Peyman, which emit pulsed ultraviolet radiation, vdo ooisir~ rcr~sooroszs,a can be used to decompose or photoablate tissue in the live cornea so as to reshape the cornea.
Specifically, a laser surgical technique known as laser in situ keratomileusis (LASIK) has been previously developed by the present inventor. In this technique, a portion of the front of a live cornea can be cut away in the form of a flap having a thiclmess of about 160 to about 180 microns. This cut portion is removed from the live cornea to expose an inner surface of the cornea. A laser beam is then directed onto the exposed inner surface to ablate a desired amount of the inner surface up to 150-180 microns deep. The cut portion is then reattached over the ablated portion of the cornea and assumes a shape conforming to that of the ablated portion.
However, because only a certain amount of cornea can be ablated without the remaining cornea becoming unstable or experiencing outbulging (eetasia), this technique is not especially effective in correcting very high myopia. That is, a typical live cornea is on average about 500 microns thick. The laser ablation technique requires that at Ieast about 200 microns of the corneal stroma remain after the ablation is completed so that instability and outbulging does not occur. Hence, this procedure cannot be effectively used to correct high myopia of greater than 15 diopters because in order to reshape the cornea to the degree necessary to alter its refractive power so as to sufficiently correct the focusing of the eye, too much of the ,~.ornea would need to be ablated.
Examples of known techniques for modifying corneal curvature, such as those discussed above, are described in U.S. Patent No. 4,994,058 to Raven et al., U.S. Patent No.

4,718,418 G~ L'Esperaace, U.S. Patent No. 5,336,261 to Barrett et al., U.S.
Patent No.
4,840,175 to Peyman, .and a publication by Jose LT Baaaquer, M.D.~ entitled ~"Keratomileusis and Keratophakia in the Surgical Correction of Aphakia".
A a~ntinuing need therefore exists for improved methods to correct very severe ametropic G mditions.
SUMMARY OF THE INVENTION
Accordingly, a primary object of the present invention is to provide a device which can be used to modify corneal curvature without experiencing the drawbacks associated with the -S-known technique discussed above, to thus correct severe ametropic conditions.
Another object of the invention is to configure the device to be positioned on the surface of the comes end reshaped while on the surface of the cornea so that the device need not be prefabricated or modifiai prior to placement on the cornea.
A further object of the invention is to provide a method for modifying the shape of a live cornea by using a device that can be placed on the surface of the live cornea and reshaped thereon.
Still a further object of the invention is to provide a method for modifying the shape of a live cornea by removing a layer of the live cornea to expose a surface underneath, placing a device on the exposed surface that can be reshaped while on the exposed surface, reshaping the device, the exposed surface, or both, and repositioning the layer over the remaiiung portion of the reshaped device so that the reshaped device, exposed surface, or both, influences the shape of the layer and thus the overall cornea.
Another object of the invention is to pmvide a method for modifying the shape of a live comes by removing a layer of the live cornea to expose a surface underneath, placing a prefabricated device, such as an annularly-shaped device, on the exposed surface, and repositioning the layer of live cornea over the device to influence the shape of the layer and thus the overall cornea without the use of a laser to reshape the exposed surface of the cosars orti~ ~e~..
The foregoing objects are basically obtained by providing a universally sized blank made of o~ ra, s3'n~etic material, or a combination of organic and synthetic unatW al, that cmz be placed on an exposed inner surface of a live cornea and ablaxed with a )seer beam, to be altered to a particular shape. The universally sad blank can be porous to allow oxygen and nutrients to pass there through. Also, the blank can be made from living cells such as a donor cornea of a human eye (e.g., as taken from an eye bank), or can be taken from a cultured comes. The blank can be disk-shaped, annularly shaped having an opening therein, or any other suitable shape.
A flap-like portion of the live cornea is removed to expose the inner surface of the cornea. The blank is positioned on the exposed inner surface of the cornea, and a laser beam ~ ~ted, for example, onto the inner surface of the cornea exposed in the opening m the blank, onto certain portions of the blank, or both, to ablate those portions of the inner surface, blank, or both, and thus reshape the inner surface, blank, or both, based on the type of 'ametrnpic condition (i.e., myopia, hyperopia or astigmatism) of the eye needing correction:
The flap-like portion of the cornea is then repositioned over the remaining portion of the blank, so that the remaining portion of the blank, ablated inner surface, or both, influences the shape of the reattached flap-like portion of the cornea, thus modifying the-curvature of the surface of the cornea. The universal blank can therefore be used to correct severe ametropic conditions, such as high myopia up to 35 diopters.
Other objects, advantages, and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the attached drawings, discloses preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWIrIGS
Referring now to the drawings which form a part of the original disclosure:
Fig. 1 is a side elevational view in section taken through the center of an eye showing the cornea, pugff and lens;
Fig. 2 is a perspective view of an embodiment of a universal blank according to the present invention;
Fig. 3 is a front elevational view of the embodiment shown in Fig. 2;
Fig. 4 is a top elevational vitw of the embodiment shown in Fig. 2;
Fig. 5 is a side elevational view in section taken through the center of an eye showing formation of a flap-like structure at the front of the cornea;
Fig. 6 is a front elevational view of the comes and flap-like structure as taken along lines VI-VI in Fig. 5;
Fig. 7 is a side elcvational view in section taken through the center of an eye and showing the flap-like section positioned to expose an inner surface of the cornea;
Fig. 8 is an enlarged side elcvational view in section taken through the center of an aye and showing placement of the embodiment of the universal blank shown in Fig. 2 on the exposed surface of the cornea;

wo ooism rcr~rsooroszs4 Fig. 9 is an enlarged side elevational view in section taken thmugh the center of an eye and illustrating the universal blank shown in Fig. 2 positioned on the exposed surface of the cornea;
Fig.10 is a front elevetional view of the cornea with the universal blank present on the acposed surface theroof as taken along lines X-X is Fig. 9;
Fig. 11 is an enlarged silo elevational view in section taken through the center of the eye showing the comes and the irradiation of a laser beam on the universal blank positioned on the a~cposed surface of the comes;
Fig.12 illustrates ablation of the center of the universal blank by the laser began;
Fig. 13 is a reducxd front elevational view of the ablated universal blank taken along lines XBI-XIII is Fig. 12;
Fig.14 is as enlarged cross-sectional view of the blank and cornea as taken along lines XN-XIV in Fig.13;
Fig. 15 is a side elevational view in section taken through the center of the eye showing the cornea and the flap-fke portion reattached over the exposed surface of the oornoa and the remaining portion of the ablated universal blank shown in Fig.14;
Fig. 16 is a side elevational view in'section taken thmugh the center of the eye illustrating ablation of the universal blank as well as a portion of the comes below the blank by the laser beam;
Fig. 17 is a side elevational view in section taken through the center of the eye ding the flap-like portion repositioned over the remaining portion of the blaalr sad ablated portion of the cornea;
Fig. 18 is a side elevational view in section taken through the center of the eye showing the comes and the irradiation of a laser beam on other peripheral portions or the universal bleak which is positioned on the exposed surface of the cornea;
Fig. 19 is a side elevational view in section taken through the center of the eye showing abiaxion of the portions of the universal blank by irradiation of the laser beam as shown in Fig. 18;
Fig. 20 is a reduced front elavational view taken along lines XX-XX in Fig.19;
Fig. 21 is as enlarged cross-sectional view taken along lines X7~-XXI in Fig.
20;

wo oo~si6sz pcTnrsoo~os2sa _g_ Fig. 22 is a side elevational view in section taken through the center of the eye showing the and the flap-like portion reattached over the exposed surf~ux of the cornea and the remaining portion of the universal blank ablated by the laser beam as shown in Fig.
19;
Fig. 23 is a side eleva~tional view in s~tion take through the cater of the eye showing ablation of portions of the universal blank and the expos~l surface of the cornea below the blank by iaadiabon of a laser beam;
Fig. 24 is a side elevational view in section talon through the center of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank as ablated by the laser bemn as shown in Fig.
23;
Fig. 25 is a side elevational view in section taken through the center of the eye showing ablation of multiple portions of the universal blank by irradiation of a laser beam;
Fig. 26 is a front elevational view of the .ablated universal blank taken along lines XXVI-XXVI in Fig. 25;
Fig. 27 is a side devational view in section taken through the center of tire eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank ablated by the laser bema as shown in Fig.
25;
Fig. 28 is a side elevational view in section taken through the center of the eye . .. . ~..$y~on of ~multigle :portions of the universal . blank and. comas by.
irradia~io~n. -of a . . . .
laser beam;
Fig. 29 is a side elevational view in section taken through the center of the aye showing the cornea. and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank as ablated by the laser beam as shown in Fig.
28;
Fig. 30 is a side elevational view in section taken ifirough the center of the aye showing ablation of the universal blank in a nonsymmetrical manner by irradiation of a laser beam;
Fig. 31 is a reduced front elevatxonal view of the ablated universal blank taken along wo oo~si6si rc°rnJSOO~oszsa lines XXXt-~ in Fig. 30;
Fig. 32 is a side elevational view in section taken through the center of the eye slmwing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the.remaining portion of the universal blank as ablated by the laser beam as shown is Fig.
30;
Fig. 33 is a side elevational view is section taken through the center of the eyc simwmg the cornea and the flap-like portion reattached ova the exposed surface of the and the remaining portion of the universal blank after a portion of the periphery of the universal blank and a portion of the exposed surface have been ablated by a laser beam;
Fig. 34 is a sido elevationai view in section taken through the center of the aye ~~g a ca~ral portion of the exposed surface of the cornea being ablated by a laser beam;
Fig. 35 is a reduced front elevational view of the ablated exposed surface of the cornea taloan along lines XXXV ~XV in Fig. 34;
Fig. 36 is a side elevational view in section taken through the cents of the eye and illustrating the universal blank shown in Fig. 2 position on the ablated exposed surface of the comp and ablation of a central portion of the universal blank by a laser beam;
Fig. 37 is a side elevational view in section taken thmugh the center of the aye showing the comes and flap-Iike portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank as ablated by the laser beam as shown in Fig. 36;
Fig. 38 is a side elevational view in section taken through the center of the eye ,. ~,g. t,~~,.cor~ea andalaG:flap~like portion reattached over the exppsux~ece of,th~:ce~~.~a , , ,. ," .
and the Wining portion of the universal blank after a etntral portion of the universal blm~k and a central portion of the ablated exposed surface of the comes have been ablated by a laser beam;
Fig 39 is a side elevational view in section taken through the center of the eye showing ablation of peripheral portions of the universal blank which is positions in the ablated exposed surface of the cornea;
Fig. 40 is a side elevational view in section taken through the center of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and remaining portion of the universal blank as ablated by the laser beam as shown in Fig. 39;

wo oois~ba2 rcrmsoomszsa -10.
Fig. 41 is a side elevational view in section taken thmugh the center of the eye showing the cornea and flap-like portion reattached over the exposed surface of the cornea end the remaining portion of the universal blank after the periphery of~the universal blank and a portion of the ablated exposed surface of the cornea surrounding the remaining porkion of the black have been ablated by a laser beam;
Fig. 42 is a side elevational view in section taken through the ceater of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and a remaining portion of the universal blank which has been ablated in a nonsynimetrical manner by a laser beam;
Fig. 43 is a side elevational view in section taken through the center of the eye shavving the cornea and the-flap-like portion reattached over the acposed surface of the comas and the remaining portion of the universal blank after a portion of the ablated exposed surface and universal blank have been ablated by a laser beans in a nonsyr~metricat manner;
Fig. 44 is a side elevational view in section taken through the center of the eye showing the cornea and the flap-ii7ce portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank of which multiple portions have been ablated by a laser beam;
Fig. 45 is a side elavational view in section taken through the center of the eye showing the c~raea and the flap-like portion r~clud over the exposed surface of the cornea and tho remaining portion of the universal blank after multiple portions of the ablated portion _. . o f the . eacposed uzface, and,muatiple. portions of the universal bla~r lutv~. blue. ak~ls~ed. .by,,a. . .. ,. . .
laser beam;
Fig. 46 is a perspective view of another embodiment of a universal bleak according to the present invention;
Fig. 47 is a front view of the embodiment shown in Fig. 46;
Fig. 48 is a bottom view of the embodiment shown in Fig. 46 as taken along lines XLVIII XLVI>I in Fig. 47;
Fig. 49 is a side elevational view in section taken through the center of the eye showing ablation of the exposed surface of the cornea by a laser beam to different depths;
Fig. 50 is a reduced front view of the cornea as taken along lines SO-SO in Fig. 49;

WO 00/51682 . PCT/US00l05284 Fig. 51 is a side elevational view in section taken through the inter of the eye showing the universal blank illustrated in Fig. 46 positioned on the exposed surface of the cornea after the exposed surface has been ablated as shown in Fig. 49;
Fig. 52 is a side elevational view in section taken thmugh ~e center of the eye showing the cornea and me flap-like portion reattached over the exposed surface of the cornea aml the remaining portion of the universal blank illustrated in Fig. 46 as ablated by the laser beam as shoaxi in Fig. 51;
Fig. 53 is a side elevational view in section taken through the center of the eye showing the comes sad the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank shown in Fig. 46 aftex a central portion of the universal blank and a central portion of the ablated exposed surface of_the.cornea have..been ablated by a laser beam;
Fig. 54 is a side elevational view in section taken through the center of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank shown in Fig. 46 whose periphery has been ablated by a laser beam;
Fig. 55 is a side elevational view in section taken through the center of the eye showing the cornea sad the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank after a portion of the periphery of the universal blank and a portion of the ablated exposed surface surrounding the remaining portion of t>~e blank ~Y~ bee~,..ablatec~,.py,~ 1r ~~a; .... . . . .." . ~ , .
.,.. . ,. .... , Fig. 56 is a side elevaxional view in section taken through the center of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank shown in Fig. 46 which has been ablated by the laser beam in a nonsymmetrical manner, Fig. 57 is a side elevational view in section taken through the center of the eye showing the cornea and the flap-like portion reattached over the exposed surface of the cornea and the remaining portion of the universal blank shown in Fig. 46 after a portion of the universal blank and a portion of the ablated exposed surface have been ablated by the laser beam in a nonsymmetrical fashion;

Fig. 58 is a side elevational view in section taken through the center of the eye showing the cornea end the flap-like portion reattached over the exposed surface of the coraea and the remaining portion of the universal blank shown in Fig. 46 of which multiple portions have been by a laser beam;
Fig. 59 is a side elevational view in section taken through the center of the eye showing the cornea end the flap-l~lce portion reattached over the exposed surface of the cornea and the ranainiag portion of the universal blank shown in Fig. 46 after multiple portions of the univ~al blank and multiple portions of the ablated exposed surface have been ablated by the laser beam;
Fig. 60 is a perspective vicw of anathcr embodimart of a universal blank according to the present invention; _ Fig. 61 is a front elevational view of the embodiment shown in Fig. 60;
Fig. 62 is a top elevational view of the embodiment shown in Fig. 60;
Fig. 63 is a perspective view of another embodiment of a universal blank according to the present invention, which is a variation of the embodimem shown in Fig. 60;
Fig. 64 is a front alcvational view of the embodiment shown in Fig. 63;
Fig. d5 is a top elevational view of the ~bodiment shown in Fig. 63;
Fig. 66 is a front elevational view of a vmiation to the embodiments shown in Figs. 60 and 63;
Fig. 67 is a side elevational view in sacdon taken through the center of an eye and ~.p~la~~anent.c~f the emlzodiment of the universal blank shown in Fig. 60 on the exposed surface of the cornea;
Fig. 68 is an enlarged side elevational view in section taken through the center of an cye and illustrating the universal blank shown in Fig. 60 positioned on the exposed surface of the cornea;
Fig. G9 is an enlarged front elevational view of the cortu;a with the univeasal blank shown in Fig. d0 presart on the exposed surface thereof as shown in Fig. 68;
Fig. 70 is a side elevationat view is section taken through the center of the eye showing the comes and the irradiation of a laser beam on the exposed surface of the cornea and on the universal blank shown in Fig. 60 positioned on the exposed surface of the comes;

wo ooisi6sz rc~rNSOOroszs4 Fig. ?1 is a side elevational view in section taken through the center of the eye illustrating the flap-like portion repositioned over the remaining portion of the universal blank shown in Fig. 60 and ablated portion of the cornea.
DETAILED DESCR>rTION OF THE PREFERRED EMBODI1VI1~1TS
Fig. l is a side elevational vices in section taken through the center of an eye 10 which includes a cornea 12, a pupil 14 and a lens 16. If the cornea 12 and lens 16 do not cooperatively focal light correctly on the retina (not shown) of the. eye to.thuus provide adequate vision, the curvature of the comes can be modified to comet the refractive power of the comes and thus correct the manner in which the light is focused with respect to the retina.
A universal blank 18 according to as embodiment of the present invention is illustirated is Figs. 2-4. As shown, the universal blank according to this embodiment is disk-shaped and has a uniform or substantially uniform thiclaress throughout, as illustrated spxifically in Fig.
3. Spxifically, the blank 18 has a first planar, substantially planar, or substantially curved surface 15, a second planar, substantially planar, or substantially curved sarfaee 17, and a perighery 19. The surfaces 15 sad 17 are arranged parallel or substantially parallel to each other with the periphery 19 being perpendicular ar substantially perpendicular to one or both saurfaces. 1~5 and 17. .. G?f coin, the surfaces 15 and 17 and the periphery ,19 need not be .
uniform but could have recesses, projections, raisod portions, or any variation in shape and text<u~e. Preferably, the univa~sal blank 18 has a diameter of about 4 to about 9 mm ~d a thickness of between about 20 to about 500 microns. Of course, the diameter and thickness of the disk shaped universal blank 18 can be of any practical size as would be appreciated by one skilled in the art. Furthermore, the universal bleak need not be disk-shaped although it is preferred as shown in the embodiment of Figs. 2-4, but can be fivsto-conical, oval, square, rectangle, or any practical shape as would be readily appreciated by one skills in the alt.
The blank 18 is preferably made of synthetic material, organic material, or a combination of both synthetic and organic material, that p~mitss all or substantially all light WO 00/51682 PCTNS00l05284 having a wavelength in the visible spectrum to pass through, but absorbs all or substantially all light having a wavelength in a laser light spectrum. For example, the blank 18 can be made of collagen, copolymer collagen, polyethylene oxide or hydrogel, or cross-linked organic material such as collagen, hyaluronic acid, mucopolysacoharide or glycoprotein, to name a few. The blank 18 is porous to allow oxygen and nutrients to pass therethrough. Also, the blank 18 can be made from a donor comes of a human eye, or can be taken from a cultured cornea. However, the blank 18 is not limited to those materials, and can be made of any suitable material, such as those disclosed in U.S. Patent No. 4,994,058 to Raven et al., U.S.
Patent No. 4,718,418 to L'Esperance, U.S. Patent No. 5,336,261 to Barrett ct al., U.S. Patent No. 4,840,175 to Peyman, and a publication by Jose I. Barraquer, M.D. entitled "Keratomileusis and Keratophakia in the Surgical Correction of Aphakia", the disclosures of which are hereby incorporated by reference herein.
The blank 18 is configured to be placed directly on an exposed inner surface of the cornea of the eye. In order to expose this inner surface of the cornea of the eye, a thin layer of the live cornea must be removed. To remove the layer of the cornea, a pie is perfoaned in which, for example, an incision 20 is made in the front portion of the cornea, as shown is Fig. S. This incision 20 is made so as to separate thin layer 22 of the comes from the remaining portion of the cornea 12. The incision can be made with a scalpel, keratome, excimer laser, or any type of surgical cutting instrument lrnown to one skilled in the art. The layer 22 can also be separated from the surface of the live cornea by any other method which may not involve making an actual incision in the cornea as may be appreciated by one skilled in the art.
The layer 22 of the cornea can be completely removed from the remaining portion of the comes 12. However, as shown in Figs. 5 and 6, it is preferable that the layer 22 of the cornea remain attached to the main portion of the live cornea 12 by an attaching or hinging portion 24 Accordingly, as shown in Fig. 7, the layer 22 of the comes is formed as a flap-like layer that is pivotally moveable about the attaching portion 24 to expose an inner surface 26 of the cornea. The layer 22 typically can be of any practical thickness, for example, 160 microns.
The universal blank 18 ' is then used to modify the curvature of the cornea in the following manner.

wo oo~si6az prr~soorosxse As shown in Figs. 8 and 9, the flap-like layer 22 is positioned so as to expose the inner surface 26 of the cornea The blank 18 is then positioned on the exposed surface of the cornoa at a position deemed suitable by the person performing the condea modifying technique. ~ w Typically, as shown in Fig. 10, the blank 18 is positioned centrally or substantially cxntially on the Exposed surface 26 with the central longitudinal axis of the blank substantially coincident with the cctdral optical axis of the eye. Of course, the blank 18 need not be positioned centrally on the exposed surface 26 as shown, but rather, its central longitudinal axis cs~a be offset from the central optical sale of the eyo.
Once positioned on the exposed surface 26 of the cornea 12, the shape of the universal blank can be modified sufficiea~tly to influ~ce the shape of the flap-like layer 22 and to thus cl~age the refi~active power of the flap-like layer sufficiently to correct the abnormality of the eye 10. Generally, every 10 micron change in curvature of the cornea will change the refisctive power of the cornea by 1 diopter.
For example, as shown in Figs. 11-14, a laser beam L is directal bo the first upper aurfacx 15 of the bleak 18 that is opposite to the socond lower surface 17 of the blank 18 that is supported on the exposed surfaoc 26 of the cornea 12. Tl~ laser beam L can be emitted from any type of laser 27 typically used in eye surgery methods, such as an excimer laser 27 or the lflCe as described in U.S. Patent No. 4,840,175.
As shown in Fig. 12, the laser beam L will begin to ablate or erode an area 32 of the blank 18 to which the laser beam is directed. Again, the area of the blank 18 to which the laser beams L is directed and which is ablated is selected to remedy a specific type of abnormality from which the aye is suflhring.
For acample, if the blank is being used to correct a myopic condition, the laser beam L
will be directed toward a central area 32 of the blank 18 so as to ablate that central area 32. As shown in Fig. 13, for example, the blank 18 is disk-shaped, and the area 32 that is ablated is circular in top plan view and is at least initially in the forts of a substantially hemispheric recess. Of course, the shape of the ablated area can be any desired shape necessary to effect correction of the particular abnormality of the eye.
As stated previously, the blank 18 is made of a material that will absorb all or substantially all light having a wavelength within the laser light spectrum.
Therefore, when ~e laser beam L is irradiated onto the blank 18, none or substantially none of the laser beam will pass through the blank 18 to ablate say portion of the cornea 12.
However, as also . . oily stated, the material of the blank 18 will allow all or dally all light having a wavelength within the visible light spectrum to pass therethrough.
Hence, as shown in Fig. 14, the laser beam L can be directed to the blank 18 until the ablated central area 32 becomes a hole with a fivstoconical wall whi~eh passes entirely through the bleak 18 to expose a portion 34 of the surface 26 of the comes 12. Of course, the hole can have a cylindrically or substantially cylindrically shaped wall, or say other shape as would be foamed by the laser beam L. As shown in Fig. 14, none or essentially none of the surface 26 of the cornea has been ablated by the laser bean.
After the laser ablation process has been completed, the flap-like layer 22 of the cornea is repositioned over the ra~navW g portion of the blank 18 slid the stnrface 26 of the cornea 12 as shown, for example, in Fig. 15. As illustrated, the shape of the remaining portion of the blank 18 will influence the shape of the flap-like layer 22 when the flap-Iike layer is repositioned over the remaining portion of the blank 18 and surface 26 of the cornea 12.
Hence, the ncfiaerive power of this flap-ldce layer 22 will be cbenged due to this change in shape. The flap-like layer 22 can be reattached to the cornea 12 by any known techniques such as sutsuing or the like.
Because the material of the blank 18 is transparent or essentially transparent to light having a wavelength within the visible light spxtrum, visible light will pass through the remaining portion to the blank 18 and enter the eye 12. However, because the reshaped flap-like layer 22 has a different refractive power, the flap-like layer 22 will refract the light passing therethrough di~rently than prior to the reshaping. Therefore, in cooperation with the lens 16 (see Fig. 1), this reshaped layer 22 will focus the light in the appropriate manner on the retina, thus correcting the ametropic coaditian of the eye.
It is further noted that the laser 27 can be used to reduce the overall thickness of the blank 18 prior to shaping the blank. For instance, the blank 18 eaa initially be about 500 microns thick for ease of handling. Then, once the blank 18 is positioned on the exposed inner surface of the cornea in the maniler described above, the inner beam L can be directed to the upper surface 15 of the blank so as to reduce the overall thiclaiess of the blank 18 as desired.

-1?-hence, a 500 micron thick blank can be reduce, for example, to about 100 microns or any suitable thickness by the laser beam L before the laser beam L is used to sculpt the blank 18 to a particular shape as shown; for example, in Figs. 1 I-I S.
Additionally, based on the severity of the abnormality from which the eye is suffering, it may be determined that the surface of the comes must be reshaped more extensively. In this event, as shown in Fig. 16, the laser beam L can be irradiated onto the area 32 of the blank 18 until the area 32 of the blank 18 is completely ablated by the laser beam and becomes a hole that passes entirely through the blank 18. Aftervvard, the laser beam L is directed onto the exposed portion of the surface 26 of the cornea so as to ablate a portion 36 of that surface.
Accordingly, as shown in Fig. 17, when the flap-like layer is repositioned over the portio~of the blank 18 and the surface 26 of the cornea 12, the ablated portion 36 of the surface of the comes 26 will also influence the shape of the repositioned flap-like layer 22. Hy using this technique, it is not necessary that the thickness of the blank 18 be changed in order to provide a more substantial change in the shape of the flap-like layer 22.
Alternatively, if the blank 18 is being used to correct a high hypeaopia condition, the laser beam L can be direxted toward the outer perimeter of the blank as shown, fior example, in Figs. 18-21. As discussed above, the blank 18 is made of a material which will absorb all or sub~ntially all of the laser beam. Therefore, as shown in Fig. 19 specifically, the blank 18 will be ablated by the laser bean, but none or substantially none of the surface 26 of the comes 12 below the ablated area 38 of the blank will be ablated.
The laser beam L can be irradiated onto the ablated area 38 of the blank 18 until that area 38 is abdown to the surface 2G of the cornea. on which the blank 18 is positioned, and the remaining portion of blank 18 thus has a fiustoconical shape. Of course, the blank 18 can be shaped in any manner by the laser beams L. As shown in Fig. 22, the flap-like layer 22 is then repositioned over the remaining portion of the blank 18 so that the remaining portion of the blank 18 the shape of the repositioned flap-like layer 22. Since the maxerial of the bleak 18 is transparent or substantially transparent to light having a wavelength in the visible light spectmm, visible Iight will pass through the remaining portion of the blank 18.
However, because the reshaped flap-like layer 22 has a different refractive power, the flap-like layer 22 will refract the light passing therethrough difftly than prior to the reshaping.

we oorsissi rcTmsoorosa~a Therefore, in cooperation with the lens 16 (see Fig. 1), this reshaped layer 22 will focus the light in the appropriate mannr~r on the retina, thus correcting the ametc~opic condition of the eye.
If a more substantial modification of the shape of the cornea is necessary to correct a more severe ametropic coition, the laser beam L cen be directed onto the surface 26 of the cornea 12 in order to ablate a portion 40 of that surface 26 as shown, for example, in Fig. 23.
As shown in Fig. 24, when the flap-ldce layer is repositioned over the remaining portion of the blank 18 and the surface 26 of the cornea 12, the ablated portion 40 of the surface 26 will also influ~ce the shape of the repositioned flap-like layer 22. Accordingly, the thickness of the blank 18 need not be increased in order to increase the degree to which the flap-like layer 22 is reshaped. High myopic conditions up to 35 diopter can be corrected by using this technique.
As discussed above, any portion or portions of the bleak 18 can be ablated to a degree necessary to correct the ametropic condition of the eye. For example, as shown in Figs. 25 and 26, the laser beam L can be directed toward a central area 32 of the blank 18 and also toward the 38 of the blank 18 to ablate inner and outer areas 32 and 38. As shown in Fig. 27, when the fl~-like layer 22 is repositioned over the surface 26 of the cornea and the remaining portion of the blank 18, the remaining portion of the blank 18 will influence the shape of the flap-like layer 22.
As shown in Fig. 28, any portion or amount of the exposed surface of the cornea 26 can be ablated as well, as long as a sufficient amount (e.g., 200 microns) of cornea _. . , . . . . is 1e8 rraraiW g no thataha remaining cornea does not experience instability or outbulging .
(ectasia) As illustrated, the laser beam L can be directed toward the smf~e 26 of the cornea undemeaxh the ablated portions 32 and 38 of the blank 18 to ablate those portions 36 and 40 of the surface 26 of the cornea 12. Accordingly, as shown in Fig. 29, the remaining portion of the blank 18 and the ablated portions 36 and 40 of the surface 26 of the cornea 12 will influence the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned over the remaining portion of the blank 18 and surface 26 of the cornea As illustiatal in Fig. 30, the laser beam L can be directed onto the blank 18 to ablate the bleak in a nonsymmetrieal manner. This type of shaping of the blank 18 is usually done to correct an astigmatic condition of the eye. For example, the blank can be sculpted to acne a _19_ substantially hemi~herical shape resembling ono-half of an egg as cut along the longitudinal axis of the eye: In other words, the blank 18 can assume a substantially hemispherical shape having a varying radius. As can be appreciated from Fig. 31, only a portion 42 of the right-side periphery of the blank 18 is ablated. Accordingly, as shown in Fig. 32, the remaining portion of the blank 18 will influence the shape of the flap-like layer 22 when the flap-lice .
layer 22 is repositioned over the remaining portion of a blank 18 and surface of the cornea 26.
As shown in Fig. 33, any portion or amount of the exposed surfaCt of the cornea 26 can be ablated in a nonsymmetrical manner as well, as long as a sufficient amount of comes (e.g., about 2(i0 microns) is left remaining so that the remaining cornea dues not experience instability or outbulging (ectasia). In this event, the laser beam L is dirocted onto the portion of the disk 18 to. be ablated, and after that portion has been ablated, the laser beam L is . _ _ _ diroctod onto the surface of the cornea 26 below the ablated portion of the blank in a meaner similar to that described, for example, with regard to Fig 16 until a porkion 44 of the surfacx 26 is ablated. Then, as shown in Fig. 33, the flap-like layer 22 is repositioned over the remaining portion of the blank 18 and the surfs 26 of the cornea so that the rosining portion of the blank I8 and the ablated portion 44 of the surface 26 of the cornea 12 will influence the shape of the flap-ldce layer 22. .
Fig. 34 shows another embodiment of the method for using a universal blank accardnng to the present invention. As illustrated, after the flap-like layer 22 has been positioned as shown in Fig. 7 to expose the inner surface 26 of the cornea, that surface 26 can ... . be ablated by. a laser beatav before the blank I8 is.positioned thereon., Speciixcally, .the laser . .,...
beam L is directed onto that exposed surface 26 to ablate the cornea 12 down to a particular depth. Typically, since the thickness of an average cornea is approximately 500 microns, the surface 26 can be ablated to any amount up to a depth of about 300 microns, which would leave a sui~cient amount (e.g., about 200 microns) of cornea left remaining so that the cornea does not experiencx instability or outbulging as discussed above.
The ablated section 46 of the surface 26 can be symmetrical about the center of the front portion of the cornea as shown in Fig. 35. Preferably, the shape of the ablated section 46 will coincide with the shape of the blank 18 that is used in modifying the cornea. In the racample illustrated in Fig. 36, the blank 18 is disk-shaped and hence, the ablated section 46 is W~ ~~Sl~

. FtWhern~onc, the diameter of the ablated section will conncide or substantially coincide with the diameter of the disk 18. Of course, the shape of the ablated section 46 can be asymmetrical, for example, and can vary to accommodate a disk having any shape as would be appreciative by one skilled in the art. Furthernnore, the center of the ablated section need not coincide with the optical axis of the eye, but rather could be offset from the optical axis.
Tho~edge 48 of the ablated section 46 will abut against the periphery 19 of the disk as shown in Fig. 36, thereby preventing or substantially preventing the disk 18 from moving laterally on the surface 26 of the cornea. However, the edge 48 need not contact the entire periphery 19 to achieve this function.
As shown in Fig. 37, the disk 18 can be ablated in the manner discussed above with regard to Figs_ 11-14 so that a -recess or hole -is formed in the caster or sub~atially is the - -center of the blank 18. In the example shown in Fig. 37, the ablation is stopped at the exposed ablated section 46 of the surface 26 so that none or substantially none of tire ablatal section 46 is further ablated. The flap-like layer 22 is then r~itioned over the remaining portion of the blank 18 so that the remaining portion of the blank 18 and the central portion 50 of the exposed ablated section 46 influences the shape of the repositioned flap-like layer 22.
Alternartively, as shown in Fig. 38, the lastr beam L can be directed onto the blank 18 and the exposed ablated section 46 in a manner similar to that described above with regard to Fig. i6. By doing this, a portion 52 of the ablated sectton 46 of the exposed surface 26 is further ablated. The ablated section 46 can be ablated by any amount as long as a suffrcieut .,... r.. . . .am.4wnt; ~e~.g" ak~Q~ut 200 -micr,~~s) of cornea 12 is left remaining.... ~ this example, the remaining portion of the blank 18 and the ablated portion 52 of the exposed ablated section 46 influences the shape of the flap-like layer 22 when the flap-hlce layer is repositioned over the blank 18 and the exposed surface 26 of the comes.
As shown in Fig. 39, the periphery of the blank 18 can be ablated in the manner similar to that discussed above with regard to Fig. 21. As shown, none or substantially nova of the previously ablated surface 46 of the exposed surface 26 is ablated by tire laser beans.
Axordingly; as shown in Fig. 40, the remaining portion of the blank 18 and the ablated section 46 of the exposed surface of the cornea influences the shape of the flap-like layer 22 when the flap-like layer is repositioned over the blank and the exposed surface 26.

Alternatively, as shown in Fig. 41, a portion S4 of the ablated section 46 of the exposed surface 26 can be further ablated by the laser beam. In this event, when the flap-like layer 22 is repositioned over the exposed surface 26 and the remaining portion 18 of the blank, the ' ablated .portion 54 and remaining portion of the blank 18 influence the shape of the fle;rldCe layer 22. v .
As farther shown in Figs. 42 and 43, a portion of the blank 18 alone or a portion of tlu blank 18 and a portion 56 of the ablated section 46 of the exposed surface 26 of the coraea 12 can be ablated in a nonsymmetrical manner. Accordingly, when the flap-like layer 22 is repositioned over the exposed surface 26 and the remaining portion of the blank, the shape of the remaining portion of the blank 18 and the ablated portion 56 influence the shape of the ~-~ ~y~ ~.
Also, as further shown in Figs. 44 and 45, multiple portions of the blank 18 alone or multiple portions of the blank and multiple portions 58 of the ablated section 46 of the exposed surface 26 can be ablated by the laser beam. Accordingly, the rcnnaining portioa of the blank 18, and the ablated portions 58 of the ablated section 46 of the exposed swrfaae influence the shape of the flap-like layer 22 when the flap-like layer is repositioned over the remaining portion of the blank 18 and the surface 26.
Another embodiment of the universal blank according to the present invention is shown in Figs. 46-48. Specifically, the blank 60 shown in Fig. 46 has a large portion 62 and a small portion 64. The large portion 62 can have any practical size and shape as could the b~ 18 shown.in Fig. 2 as discussed above, sand can be made of the same type of materials as . ,. ,. . .. .
the blank 18.
In the exempla shown in Fig. 46, the large portion 62 of the blank 60 is disk-sbaped and has a diameter of about 4 to about 9 millimeters and a thickness of between about 20 and about 500 microns. Of course, the diameter and thickness of the blank 60 can be of any practical size that would be appreciated by one ski.Iled in the art.
As fmrti~cr illustrated in Figs. 47 and 48, the small portion 64 of the blank 60 is also disk-shaped, but has a small diameter than the large portion 62. The diameter of small portion 64 can be any practical size, such as a small disk shaped projection having a nominal diameter up to a disk-shaped projection having a diameter only a fraction smaller than the diameter of wo oo~stssz pcrnrsoorosis4 the large shaped portion 62. Of course, the small portion 64 need not be disk shaped, but can have any practical shape as would be appreciative by one skilled in the art.
Furthermore, the large portion 62 and small portion 64 can have shapes different from each other: Hence; for example, the large portion 62 can be disk-shaped while the Snnall portion 64 can be oval or rectangularly shaped.
The large portion 62 has a fast planar or substantially planar surface 63, a second planar or substantially planar surface 65, and a periphery 66. The surfaces 63 and 65 can be parallel or substantially parallel to each other, and the periphery 66 can be perpendicular to one or both of the surfaces 63 and 65. Of course, the surfaces 63 and 65 and the periphery 66 need not be Booth but can have projected portions, recesses or any type of .
The small portion 64 is integral with or attachable to the large portion 62.
and a planar or substantially surface 68 and a periphery 69. The surface 68 can be parallel or substantially parallel to one or both of the ~ 63 and 65 of the large portion 62, and the periphery 69 could be perpendicular or substantially perpendicular to the surface 68. Of course, the surface 68 and periphery 69 need not be smooth but can have projected portions, recesses or any type of texhun.
An embodiment of a method for using the universal blank 60 according to the present invention is shown in Fig. 49. Specifically, the surface of the cornea 26 th~x has been exposed by foaming and positioning the fl~-like layer 22 in the manner discussed above is ablated in tlas manner shown in Fig. 49. That is, the exposed surface 26 is ablated to different depths so as to a$sume a shape wl~icl~ cau a~ommodate the blank 60. Hence, an outer aectio~ '14 o~.tho _... . . .
exposed surface 26 is ablated to a first depth, while an inner section 71 is ablated to a second depth gxeater than the first depth. The depths of the ablated inner and outer sections 70 sad 71 can be any amount which would allow a sui~cient amount of cornea 12 (e.g., about 200 microns) to remain so that the remaining cornea does not expaiarCing distortion or outbulging. It is noted that this step-shaped blank 60 provides an advantage over a uniformly shaped blank 18 in this regard, because less volume of cornea can be ablated to form a recess which will accommodato the smaller portion 64 of the blank 60 and thus point the blank 60 from shifring on the surface of the cornea. That is, the volume of cornea removed to form section 71 is less than the volume of comes removed to form section 46 (Fig.
34).

As shown in Fig. 51, the blank 60 is positioned on the ablated sections 70 and 71 of the exposed surface 26 so that the surface 68 of the small portion 64 of the blank 60 contacts or substantially contacts the ablated section 71 while the surface 65 of the large portion 62 of the blank 60 contacts or substantially contacts the ablated section 70 as shown. As further shown, an edge 72 of the ablated section 71 contacts the periphery 66 of the large portion of the blank 60, while an edge 74 of the~ablated section 71 contacts the periphery 69 of the small portion 64. of the blank 60. Of course, the sizes and shapes of the ablated section 70 and 71 can be made to conform or substantially conform with the sizes and shapes of the large and small portions 62 and 64, respectively, of the blank 60, and can thus be any practical size and shape as would be appreciated by one skilled in the art. Also, the ablated sections 70 and 71 need not be made symmetrical about the central optical axis of the eye, but rather, could be offset from the cent<al optical axis of the eye and from each other. The edges 72 and 74 of the ablated sections 70 and 71, respectively, can contact the peripheries 66 and 69, respectively, in their entirety or at various locations.
As further shown in Fig. 51, the laser beam L is irradiated onto the blank 60 in a meaner similar to that described above with regard to Figs. 11-14 to ablate a central or substantially central portion of the blank 60 as shown in Fig. 52. That ablated portion can be, for example, a substantially hemispherical recess as discussed above with regard to Figs. 11-14. As further shown in Fig. 52, none or substantially none of the ablated section 71 is further ablated by this laser beam. Accordingly, the surface of the ablated section 71 and the remaining portion of the blank 60 influence the shape of the. flap-like layer 22 when the flap-like lays 22 is repositioned over the blank 60 and the exposed surface 26.
Alternatively, shown in Fig. 53, a portion 76 of the ablated section 71 below the ablated portion of the blank 60 can be further ablated by the laser beam to any depth which would allow a sufficient amount (e.g., about 200 microns) of the cornea 12 to remain.
Accordingly, the ablated portion ?6 and remaining portion of the blank 60 influence the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned back over the exposed surface 26 and the remaiining portion of the disk 60.
As further shown in Fig. 54, multiple portion of the blank 60 can be ablated in a manner similar to that in which the blank 18 is ablated as described, for example, with respect to Figs. 18-22 above. Furthermore, as shown in Fig. 55, the laser beam can be directed onto the ablated section 70 of the exposed surface 26 to ablate portion 78 of that ablated section 70.
Accordingly, as shown in Fig. 54, the remaining portion of the blank 60 and the ablated section 70 influence the shape of the flap-lflce layer 22 when the flap-like layer 22 is repositioned over the exposed surface 26 and the remaining portion of the blank 60.
Conversely, as shown in Fig. 55, the remaining portion of the blank 60 and the further ablated portion 78 of the ablated section 70 of the exposed surface 26 influencx the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned over the exposed surface 26 in the remaining portion of the blank 60.
As further shown in Figs. 56 and 57, the blank 60 and ablated section 70 of the exposed surface 26 can be ablated by the laser beam in a nonsymmetrical manner.
Accordingly, as shown in Fig. 56, the n~naining portion of the blank 60 and the ablated section 70 influence the shape of the flap-like layer 22 when the flap-like layer is repositioned over the surface 26 in the remaining pardon of the blank 60. As shown in Fig.
57, the nonsymmetrieal ablated portion 80 and the remaining portion of the blank 60 influence the shape of the flap-Iike layer 22 when the flap-like layer is repositioned over the exposed svafa<x 26 and the remaining portion of the blank 60.
As shown in Figs. 58 and 59, the blank 60 and ablated section 70 can be ablated at multiple locations in a warmer similar to that in which the blank 18 and surface 26 are ablated as described above with regard to Figs. 25-29. Accordingly, as shown in Fig.
58, the remaining portion of the blank 60 and the ablated sections 70 and 71 of the exposed surface 26 influence the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned over the exposed surface 26 and the blank 60. Alternatively, as shown in Fig. 59, the further ablated portion 82 of the ablated section 70, the fiuther ablatod portion 84 of the ablated section 71, aad the remaining portion of the blank 60 influence the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned over the remaining portion blank 60 and the exposed surface 26.
Another embodiment of the universal blank according to the present invention is shown in Figs. 60-62. Specifically, the blank 86 is annular or ring-shaped having an upper planar, substantially planar or substantially curved surface 88, a lower planar, substantially WO 00~5168Z PCT/US00l05284 planar surface or substantially curved 90, an outer wall 92 and an inner wall 94 defining an opening 96 through the blank 86. The opening 96 can be circular in shape, as shown, err any suitable . shape. such as oval, multi-sided (e.g., square, rectangular, triangular), and so on. The opening 96 also need not pass entirely through the blank 86 as shown, but can be a recess in the blank 86. The s88 and 90 can be parallel or substantially parallel to each other, or at any suitable angle, and either the outer wall 92, the inner wall 94, or both, can be perpendicular to one or both of the' surfaces 88 and 90, or can be at any suitable angle with r~p~t to the s~ufaces 88 and 90. Also, the surfaces 88 and 90, the outer wall 92 and inner wall 94 need not be smooth, but eau have projected portions, recesses or any type of texture or of curvatum, and can have any shape such as concave, convex, tonic, and so on.
The blank 86 eau be made of the soma types of materials as blanks 18 and 60 discu~ed above. Typically, the blank 86 has an outer diameter within a range of about 4 mm to about 11 mm, and opening 96 has a diameter of about 0.1 mm to about 10 mm, depending on the siu of the outer diameter. Furthe,~more, the blank 86 can have a thickness ranging from about ~m to about 1000 Vim, with a thickness of about 144 ~m being a suitable exemplary thickness. In general, about 12 um of blank thickness provides a correction of about 1 diopter.
Hence, a 144 ~m thick blank provides for a comction of about 12 diopters:
Also, the bl~k itself can have any suitable shape, such as oval, square, rectangular, polygonal, and so on. As shown, for example, in Figs. 63-65, the blank can be an oval shapod blank 98 having an upper surface 100, a lower surface 102, an outer wall 104 and an inner wall 106 debning an opening 108 through the blank 98 which, like opening 96, can be circular, oval, or any other suitable shape, and eaa pass entirely through the blank 98 or be a recess in the blank 98. Blank 98 can be made of the same types of materials as blanks 18, 60 and 86 discussod above, and can have similar dimensions. That is, the largest overall outer diameter of blank 98 can range from about 4 nun tv about 11 mm, and the largest overall diameter of opening 108 can range from about 0.1 mm to about 10 mm, depending on the size of the outer diameter.
Furthermore, the blank 98 can have a thickness ranging from about 10 ~m to about 1000 Vim, with a ~ielai~s of about 144 Nxn being a suitable exanplary thickness. Also, the 100 and 102 can be parallel or substantially parallel to each other, or at any suitable WO 00!516$2 PCT/US00/05284 angle, and either the outer wall 104, the inner wall 106, or both, can be perpendicular to one or both of the surfaces 100 and 102, or can be at any suitable angle with respect to the surfaces 100 and 102. Also, as with blank 100, the surfaces 100 and 102, the outer wall 104 and inner wall 106 need not be smooth, but can have projected portions, recesses or any type of texture ~ degree of curvature.
In addition, as shown in Fig. 66, either of blanks 86 and 98 can have a varying thickness ranging from about 20 lun to about S00 Vim, which is especially useful in correcting astiganatic conditions. Furthermore, the blanks 86 and 98 need not be completely annular.
That is, blanks 86 and 98 can include a gap 110 and 112, respectively, as shown in Figs. 62 and 65, which can be of any suitable width. The gaps 110 and 112 can be wedge-shaped as shown. That is, the surfaces 114 and 116 forming gap 110 can extend angularly with respect to each other as shown. Alternatively, gap 110 can be slot-like, with the s~ufaces 114 and 116 parallel or substantially parallel to each other. Likewise, the suzfaces 118 and 120 forming gap 112 can extend angularly with respect to each other as shown.
Alternatively, gap 112 can be slot-like, with the surfaces .118 and 120 extending parallel or substantially parallel to each other. The surfaces 114, 116, 118 and 120 can be smooth, or can have projections or any suitable texture. Also, instead of gaps, the regions designated by 110 and 112 can be regions in which the thickness of the respective blanks 86 and 98 are greater than or less than the overall thickensses of the remainder of the respective blanks 86 and 98.
An embodiment of a method for using the universal blanks 86 and 98 according to the present invention is shown in Figs. 67-71, which is similar to the methods described above regarding blank 18. For exemplary purposes, Figs. 67-71 illustrate blank 86.
However, bl~k 98 is used in a similar manner.
Specifically, a flap-like layer 22 having a diameter of about 8 mm to about 9 mm and a thickness of about 160 Eun is separated from the cornea 12 in the manner described above to expose a surface 26. As shown in Figs. 67-69, the blank 86 is positioned on the exposed surface 26 so that the surface 90 contacts the sui~aee 26. Typically, the blank 86 (or 98) is positioned on the surface 26 so that its center is substantially aligned with the optical axis of the eye 10. However, the blank 86 (or 98) can be placed at any location on surface 26.
As further shown in Fig. 70, the laser beam L is irradiated onto the portion of the wo ooist6sZ pcrnrsooroszs4 exposed surface 26 which remains exposed by the opening 96 (or 108) in the blank 86 (or 98), and ablates that portion of the surface 26. Alternatively or in addition, the laser beam L can be irradiated onto the bleak 86 (or 98) to ablate a portion of the blank.
Typically, the portion of the blmdC 86 (or 98) that is ablated is that which inchtdes inner wall 94 (or 106), thus enlarging the diameter of opening 96 (or 108).
Aceot~dingly, as shown in Fig. 70, a portion 122 of the surface 26, a portion 124 of the blank 86 (or 98), or both are ablated by the laser beam L. The surface 26 of the cornea 12 can be ablated up to any suitable depth as discussed above, to correct for the vision disorder as appropriate. Also, the portion of the blank 86 (or 98) can be ablated entirely, or by a desired amount, to correct for the vision disorder as appropriate. It is further noted that the ablation of the exposed surface 26 and blank 86 (or 98) need not occur evonly. That is, some of the exposed surface 26 can be ablated to a larger depth than other portions of the exposed surface 26 being ablated. L~cewise, some of the blank 86 (or 98) can be ablated to a depth greater than that to which other portions of the blank are ablated. In any event, the degree to which the exposed surface 26 of the cornea 12 and, if necessary, the blank 86 (or 98) is ablated is dependent on the severity of the vision disorder being corrected, as well as the type of vision disorder (e.g., myopia, hyperopia or astigmatism).
Once the desired amount of ablation has occurred, the flap-like layer 22 is repositioned over the blank 86 (or 98) and exposed surface 26. as shown in Fig. 71. In a manner similar to that described above, the flap-like layer 22 rests on the blank 86 (or 98) and surface 26 in a relaxed steals. Accordingly, the ablated surface 26 and the remaining portion of the blank 86 , _ . ,.
(or 98) influence the shape of the flap-like layer 22 when the flap-like layer 22 is repositioned over the blank aad the exposed surface 26. The new shoe assumed by the flap-like layer 22 thus corrects the refractive power of the eye 10 as necessary to correct the vision disorder. .
Another embodiment of the universal blank shown in Figs. 60-62, for example, allows for the specific parameters of the blank to be prefabricated, such as by ablation by an excimer laser or shaping in a cryolathe, so that the lower (posterior) swface 90 of the blank 86 has the same or similar radius of curvature as the preoperative live cornea. The upper (anterior) surface 88 may have a curvature which is concave, convex, tonic or parallel in relation to posterior surface 90, or aay other suitable curvature. Posterior surface 90 can also have any of these c~a natures if sired. The thiclrness of the blank 86, the curve of anterior surface 88, the Iangth of the gap 110 (or thickness of the region between surfaces 118 and 120) cu<a be prefabricated to correct ametropia and astir without the use of laser ablation. The univeasal blank having die shape shown in Fig. 63-65 can have similar prefabricated characteristics, as desired.
The prefabricated blank 86 (as well as blank 98) can then be used in a manner s;milar to that descn'bed above. That is, the flap-lie layer 22 having a diameter of about 8 mm to about 9 rom and a thickness of about 160 Tun is separated from the cornea 12 in the meaner described above to expose a surface 26. The blank 86 is positioned on the exposed surface 26 so that the surface 90 contacts the surface 26. Typically, the blank 86 (or 98) is positioned on the surface 26 so that its center is substantially aligned with the optical axis of the eye 10.
Howawer, the dank 86 (or 98) can be placed at any location on surface 26.
The flap-like layer 22 is then repositioned over the blank 86 (or 98) and exposed stu~x 26. In a manner similar to that described above, the flap-like layer 22 rests on the blank 86 (or 98) and swface 26 in a relaxed state. Accordingly, the wcposed sui~ace 26 and the prefabricated blank 86 (or 98) in$u~ the shape of the flap-Iike layer 22 when the flap-like layer 22 is repositioned over the blank and the exposed surface 26, without ablating any portion of the flap-ldce layer 22, the blank 86 (or 98), or exposed surfacx 22. The new shape assumed by the $ap-like Iayer 22 thus the refractive power of the eye 10 as necessary to corrxt the vision disorder.
Tn addition, blanks 18 and 60 can be prefabricated in a manner similar to blank 86, and used in a snanner similar to blank 86 without laser ablation as described above.
Once the flap-Idce layer 22 and surface 26 heat, the patient's eyesight can be tested. If it is determined that the vision disorder has not be satisfactorily corrected, the flap-like laytr 22 can be again separated from the cornea 12, and the surface 26 and/ or blank 86 (or 98) can be further ablated as necessary. Also, if deemed appropriate, an additional blank or blanks having the same or different shape and characteristics of the existing blank can be stacked an the surface 88 (or 100) of the blank 86 (or 98), and the additional blank or blanks can be ablated as necessary. The flap-Tike layer 22 can be then repositioned over the blank and surface 26, allowed to heal, and the eyesight can again be tested. The steps of removing the WO 00/51682 PC1'IUS00105284 flap-like layer 22 and ablation, as well as the addition of more blanks, can be repeated as many times as necessary to properly correct the vision disorder. It is desirable that vision up to 20/15 or 20/10 can be achieved.
Due to the presence of openings 88 and 108 in blanks 86 and 98, respectively, blanks 86 and 98 each uses less material than a solid blank (e.g., blank 18 discussed about) having the same overall diam~r and thic~s. Moreover, because the openings are already preset in the blanks 86 and 98, it may only be necessary to ablate the exposed s~uibce of the cornea through the opening in the blank to achieve the appropriate corneal modification. In this event, less laser usage and thus, less ovotall surgical time, is required.
Although only a few exemplary embodiments of this inv~tion have been descri'bod in _ detail .above, those skilled in the art will readily appreciate that many modifi~ions are possible in the exennplary ~nbodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intends to be included within the scope of this invention as defined in the following claims.

Claims

What is claimed is:

1. A method of modifying the curvature of a patient's live cornea, comprising the steps of:
separating a layer of said live comes from the front of said live cornea;
moving said separated layer to expose an internal surface of said live cornea underneath said separated layer;
positioning a blank, having an opening therein, on said internal surface of said live cornea;
directing a laser beam (a) through said opening onto said internal surface of said live to ablate a portion of said internal surface, or (b) onto a portion of said blank to ablate said portion of said blank, or both (a) and (b), while leaving an unablated portion of said blank on said internal surface of said live cornea; and repositioning said separated layer of said live cornea back over said internal surface of said live cornea and said unablated portion of said blank, so that the shape of the internal surface and said unablated portion of said blank influences the shape of said repositioned separated layer of said live cornea.

2. A method according to claim 1, wherein the separating step comprises one of the following steps:
directing a laser beam onto said live cornea to separate said separated layer from said live cornea; and using a blade to cut an incision into said live cornea to separate said separated layer from said live cornea.

3. A method according to claim 1, wherein the separating step comprises the step of forming said separated layer as a flap having an attaching portion which remains to said live cornea.

4. A method according to claim 3, wherein the separated layer moving step comprises the step of moving said separated layer about said attaching portion to expose said internal surface.

5. A method according to claim 1, wherein the laser beam directing step comprises the step of directing said laser beam onto said blank to ablate said portion of said blank without ablating substantially any of said internal surface.

6. A method according to claim 1, wherein said portion of said blank includes surfaces of said blank defining said opening in said blank.

7. A-method according to claim 1, wherein the laser beam directing step comprises the step of directing said laser beam onto said internal surface to ablate said portion of said internal surface without ablating substantially any of said blank.

8. A method according to claim 1, wherein the laser beam directing step comprises the step of g said laser beam onto said blank and onto said inner surface to ablate said portion of said blank and said portion of said internal surface.

9. A method according to claim 1, wherein said blank is annular-shaped

10. A method according to claim 1, wherein said blank is oval-shaped.

11. A blank, adaptable for use in modifying the curvature of a patient's live cornea, comprising:
a first surface adapted for placement directly on a surface of said patient's live cornea;
a second surface adapted to be exposed to a laser beam;
a wall surface, extending between said first and second surfaces, and defining an opening in said blank;

said blank comprising a material whose properties permit light having a wavelength within the visible spectrum to pass therethrough and prevent substantially all light having a wavelength within the laser light spectrum from passing therethrough.

12. A blank according to claim 11, wherein said material is adapted to be ablated by laser light.

13. A blank according to claim 11, wherein the thickness of said blank is within a range of about 10 to about 1000 microns, and a maximum length of at least one of said first and second surfaces of said blank is within a range of about 4 mm to about 11 mm.

14. A blank according to claim 11, said blank is annularly-shaped having said first and second surfaces on opposite sides thereof, the thickness of said blank is within a range of about 10 to about 1000 microns, the diameter of said blank is within a range of about 4 mm to about 11 mm, and the diameter of said opening is within a range of about 0.1 mm to about 10 mm.

15. A blank according to claim 11, wherein said material is one of organic and synthetic material.

16. A blank according to claim 11, wherein said material is one of collagen, copolymer collagen, polyethylene oxide and hydrogel.

17. A blank according to claim 11, wherein said material includes one of the following cross-linked organic materials: collagen, hyaluronic acid, mucopolysaccharide and glycoprotein.

18. A blank according to claim 11, wherein said blank has a substantially uniform thickness between said first and second surfaces.

19. A blank according to claim 11, when said first and second surfaces each are substantially planar surfaces, or substantially curved surfaces.

20. A blank according to claim 19, wherein said first and second surd are substantially parallel to each other.

21. A blank according to claim 19, wherein said second surface is convex, concave, or tonic in relation to said first surface.

22. A blank according to claim 11, wherein said wall surface extends at an angle other than 0° with respect to said first and second surfaces.

23. A blank according to claim 11, wherein said wall surface is convex, concave or tonic.

24. A blank according to claim 11, wherein said wall surface extends substantially perpendicularly with respect to at least one of said first and second surfaces.

25. A blank according to claim 24, wherein said wall extends substantially perpendicularly with respect to said first and second surfaces.

26. A blank according to claim 11, wherein said blank is annularly-shaped.

27. A blank according to claim 11, wherein said blank is oval-shaped.

28. A blank according to claim 11, wherein said wall surface defines said opening as a substantially circularly-shaped opening.

29. A blank according to claim 11, wherein said wall surface defines said opening as an oval-shaped opening.