Abstract:
A refractive intraocular lens and method of locating the lens within the eye and attaching the lens to the iris. The refractive intraocular lens may be attached via staples, a fastener or by the tip of the haptics.

Description:
FIELD OF THE INVENTION 
     This invention relates generally to the field of intraocular implant lenses and more particularly, to intraocular implant lenses for use in refractive vision correction. 
     BACKGROUND OF THE INVENTION 
     It has long been a goal of ophthalmic surgeons to provide patients with alternatives to eyeglasses. Witness the development of the contact lens, radial keratotomy and lasik or laser vision correction surgery. It is estimated that in the year 2000, over two million lasik procedures will be performed. Notwithstanding the popularity of laser surgery, it is not without its drawbacks and deficiencies. For example, recent data has shown that approximately 5-10% of the patients undergoing laser refractive surgery will have suboptimal results such as, a final vision correction which still requires some sort of optical correction or the patient will experience cataract-like “halos”. In addition, it has been estimated that up to 50% of the patients post laser surgery experience dry eye symptoms on an ongoing basis. 
     In response to the foregoing, ophthalmic surgeons have turned to intraocular implant surgery in an effort to advance the art of refractive vision correction. For example, U.S. Pat. No. 5,192,319 to Worst discloses an intraocular refractive lens which is surgically positioned in the anterior chamber and is used in addition to the natural lens to correct for refraction error. The lens comprises an optical portion (the optic) having an inner concave and an outer convex shape. Attached to the outer periphery of the optic is one or more pairs of flexible pincer arms which are adapted to pinch a small portion of the anterior surface of the iris to maintain the implant in place. Notwithstanding the foregoing, the Worst lens has not been widely adopted. This is because the lens requires a hard, non-flexible material to fixate to the iris, thus requiring a large 6 mm or more incision. In addition, the Worst lens is difficult to implant and requires a two handed ambidextrous surgical technique to insert and attach to the iris, skills, which are found in relatively few ophthalmologists. 
     Other anterior chamber implants have also been attempted without success. For example, U.S. Pat. No. 4,575,374 to Anis discloses an anterior chamber lens comprising an optic and four haptics, each of which flexes independently of the others. U.S. Pat. No. 4,166,293 also to Anis discloses an anterior chamber implant for cataract replacement having an optic and three loops that extend downward and are adapted to fit behind the iris. A fourth loop overlies on of the other loops and overlies the iris when the implant is in place within the eye. The implant is held in place by an attachment member, which connects the fourth loop with the underlying loop by penetrating through the iris. Another anterior chamber implantable lens is disclosed in U.S. Pat. No. 4,177,526 to Kuppinger wherein a pair of opposing arms are attached to the optic. The respective arms are inserted behind the iris and pinch the rear of the iris to hold the implant in place. Another anterior chamber implant lens is disclosed in U.S. Pat. No. 5,047,052 to Dubroff, which teaches an optic, and four haptics extend outwardly therefrom. The haptics are flexible and independently movable. Further, once the implant is inserted and positioned by conventional means, the ends of the haptics are adapted to rest within the optical angle, i.e., the intersection of the cornea and the iris. It is notable that none of the foregoing implant lenses have been widely adopted and in fact only one of the lens (i.e., Worst Lens) is currently in limited use in the European market, as they all experienced surgical or clinical failures including, lens insertion and attachment problems, intraocular or iris bleeding, inflammation, tissue deformation, potential lens induced glaucoma. 
     Accordingly, it is an object of the present invention to provide an improved refractive implant, which solves the aforementioned problems. 
     A further object of the present invention is to provide an improved refractive implant, which is minimally surgically invasive. 
     Another object of the present invention is to provide an improved refractive implant having reduced side-effects, for example dry eyes and inflammation. 
     An additional object of the present invention is to provide an improved refractive implant, which is easily implantable and removable, if necessary. 
     A still further object of the present invention is to provide an improved refractive implant, which accurately corrects vision, thus obviating the need for subsequent surgeries. 
     A correlated object of the present invention is to provide an improved refractive implant, which is easy to manufacture. 
     Yet another object of the present invention is to provide an improved refractive implant, which does not require expensive equipment, such as lasers. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a refractive intraocular lens that is adapted to be implanted within the eye and which is supported by the iris. The lens is characterized by its ability to be easily inserted and removed with minimal trauma to the eye tissues. The lens comprises an optic for producing a preselected optical effect having an anterior side, a posterior side and an outer peripheral edge. The lens may be foldable or deformable. A haptic is connected to the optic and extends outwardly therefrom. The haptic includes a proximal end, a distal end and an intermediate segment positioned therebetween. The proximal end is connected to the optic and the intermediate segment projects downwardly and away from the posterior side of the optic and the distal end terminates in a pointed tip. The intermediate segment includes a shoulder for supporting the lens on the iris. The distal end of the haptic includes an iris fixation means for attaching the lens to the iris wherein the tip is constructed and arranged to penetrate the iris. 
     In a second embodiment of the invention, the refractive intraocular lens is attached to the iris by means of a staple, which is adapted to overlie and straddle a portion of the haptic. The staple is compressible from a first relaxed state to a second expanded state such that when the staple is expanded and placed in an overlying straddling relation to the haptic and is released, the staple contracts and attaches the iris, thereby fixing the position of the intraocular lens thereon. Additionally, the staple could be attached to the iris in the reverse manner from that which is described above. 
     In a third embodiment of the invention, at least one of the haptics includes a hole defining an opening. A fastener is adapted to be received within the opening and to expandingly grip the iris tissue. More specifically, the fastener comprises a shaft having a top end and a bottom end. The bottom end includes includes a flexible barb and the top has a diameter that is greater than the diameter of the opening such that when the fastener is inserted in the opening, the barb is retracted and the fastener slides in the opening and when the barb exits the bottom of the opening, the iris is hooked and the barb becomes embedded therein, thus attaching the intraocular lens to the iris. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the following detailed description and appended claims, and upon reference to the accompanying drawings. 
     FIG. 1 is a cross section of a human eye. 
     FIG. 2 is a cross section of a human eye with an implant according to the present invention affixed to the iris. 
     FIG. 3 is a perspective view of an implant lens according to the present invention. 
     FIG. 4 is a plan view of an implant lens according to the present invention. 
     FIG. 5 is an end view of an implant lens according to the present invention. 
     FIG. 6 is an end view of an implant lens according to the present invention. 
     FIG. 7 is a plan view of an implant lens according to the present invention and having a second arrangement of tips. 
     FIG. 8 is an end view of an implant lens according to the present invention and having a second arrangment of tips. 
     FIG. 9 is a plan view of a second embodiment of the implant lens according to the present invention. 
     FIG. 10 is a sectional view taken along line A—A of the embodiment of the implant lens of FIG.  9 . 
     FIG. 11 is a plan view of the second embodiment of the implant lens according to the present invention and having a different haptic arrangment. 
     FIG. 12 is a sectional view taken along line A—A of the embodiment of the implant lens of FIG.  11 . 
     FIG. 13 is a plan view of the second embodiment of the implant lens according to the present invention and having a third haptic arrangment. 
     FIG. 14 is a sectional view taken along line A—A of the embodiment of the implant lens of FIG.  13 . 
     FIG. 15 is a plan view of a third embodiment of the implant lens according to the present invention. 
     FIG. 16 is a sectional view taken along line A—A of FIG. 15 of the implant lens according to the present invention. 
     FIG. 17 is a side view of the fastening means according to the present invention being pushed downward through the haptic and into the iris. 
     FIG. 18 is a perspective view of the staple insertion tool according to the present invention. 
     FIG. 19 is an exploded view of the staple insertion tool according to the present invention. 
     FIG. 20 is a perspective view of a portion of the staple insertion tool according to the present invention. 
     FIG. 21 is a perspective view of the trap lock and gripping fingers portion of the staple insertion tool according to the present invention. 
     FIG. 22 is a side view of the gripping fingers portion of the staple insertion tool in the open staple releasing position. 
     FIG. 23 is a side view of the gripping fingers portion of the staple insertion tool in the closed staple gripping position. 
     FIG. 24 is a perspective view of the staple insertion tool according to the present invention in the closed staple gripping mode. 
     FIG. 25 is a detailed perspective view, partially broken away, of the gripping portion of the tool as illustrated in FIG.  24 . 
     FIG. 26 is a perspective view of the staple insertion tool according to the present invention in the open staple releasing mode. 
     FIG. 27 is a detailed perspective view, partially broken away, of the gripping portion of the tool as illustrated in FIG.  26   
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     While the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which particular embodiments are shown, it is to be understood at the outset that persons skilled in the art may modify the invention herein described while still achieving the favorable results of this invention. Accordingly, the description which follows is to be understood as a broad teaching disclosure directed to persons of skill in the appropriate arts and not as limiting upon the present invention. 
     Referring now to the drawings and particularly to FIG. 1 in which a human eye is schematically illustrated. The structures of the eye include the cornea  50 , iris  52 , sclera  54 , vitreous  56 , anterior chamber  58 , chamber angle  60 , trabecular meshwork  62 , posterior chamber  64  and human crystalline lens  66 . While the description makes specific reference to the human eye, it will be understood that the invention may be applied to various animals with only minor modifications. For example, mammals such as dogs, cats and horses and the like may suffer injuries when their eyesight deteriorates with age and vision correction surgery as contemplated by this invention may prevent injury and thus extend their useful life. 
     Turning now to FIGS. 2 through 8, a first embodiment of the invention is there illustrated. The intraocular lens generally indicated at  100  is adapted to be implanted within the eye and includes an optical means or optic  102  and a single or a plurality of haptic means or haptics  110 . The optic is generally circular and has an anterior side  104 , a posterior side  106  and an outer peripheral edge  108 . The diameter of the optic  102  is in the range of approximately 5 mm to 6 mm. In addition, the optic  102  will have varying anterior and posterior curvatures, depending on whether myopia or hyperopia is being corrected. Further curvature variations are added for the correction of cylinder (Astigmatism), presbyopia, bi-focal or multi-focal. The characteristics of the particular optic  102  selected are left to the surgical judgement of the ophthalmologist performing the implant procedure. In addition, the optic  102  and the haptics  110  must be made of a material, which is biologically inert and the optic  102  must additionally be made of a material, which satisfies the necessary optical and surgical insertion requirements. The term “biologically inert” is generally understood in the art to be a material which is not absorbed by the body fluids and which does not cause any adverse reaction when implanted. Commonly used materials alone or in combination for intraocular lenses are silicone, acrylic, collagen, hydrogel and polymethylmethacrylate. Other suitable materials may include ophthalmic glass, quartz and other polymeric materials. 
     A single or a plurality of haptics  110  are connected to the optic  100 . The haptics extend outward from the optic and are spaced apart from each other. Each of haptics  110  include a proximal end  112  which is connected to the outer peripheral edge  108  of the optic, an intermediate segment  114 , and a distal end  116 . The haptics also include a riser means or riser for maintaining the optic in spaced relation from the iris. In the illustrated embodiment, the intermediate segment  114  includes the riser and it projects downwardly and away from the posterior side of the optic  102  in order to “vault” or provide spacing between the underside of the implant and the surface of the iris. In addition, the intermediate segment  114  includes a shoulder  115  which is adapted to support the implant  100  on the surface of the iris  52 . The distal end  116  has at it&#39;s terminating end, an iris fixation means for attaching the intraocular lens to the iris in the form of a pointed tip  118  which is adapted to penetrate the iris and defines a point of attachment to the iris. In the preferred embodiment, penetration is a portion of, but less than the entire iris, and in the preferred embodiment is approximately one half the thickness of the iris. The amount of penetation will vary with the mass of the implant, the number and structure of haptics and other factors, It will be noted that the haptics are of sufficient length so as to avoid interfering with the muscles that control the opening and closing of the pupil. Alternatively, the staple may be designed such that it pinches, but does not nesessarily penetrate the iris, thereby attaching the intraocular lens. With respect to the embodiment illustrated in FIGS. 2 through 6, four haptics are shown. They are divided into two pairs, each of which extends outwardly and away from the optic at opposite ends thereof. In addition, the respective pointed tips  118  of each pair face inwardly towards each other. The embodiment as shown in FIGS. 7-8 is essentially identical as that just discussed, however the respective pointed tips  118  are in opposing relation or facing outwardly. Either arrangement will adequately anchor the implant  100  on the iris. 
     In operation, an incision on the order of 4.0 mm is made in the cornea or sclera by the ophthalmic surgeon. Using forceps or intraocular lens insertion instruments, the implant  100  may be folded, deformed or rolled to reduce the overall insertion size, inserted into the eye and centered over the pupillary opening. Each of the haptics is then manipulated such that the tips penetrate the iris. It will be noted that the respective intermediate segments  114  of the haptics  110  include a shoulder portion, which rests on the iris and limits the depth to which the tips  118  can penetrate. 
     A second embodiment of the invention is illustrated in FIGS. 9 through 14 wherein an optical implant  200  is adapted to be implanted within the eye and to be attached to the iris. The implant comprises an optical means or optic  202  for producing a preselected optical effect. The optic  202  has an anterior side  204 , a posterior side  206  and an outer peripheral edge  208 . A single or plurality of haptic means or haptics  210  are connected to the optic  202 . A staple means or staple  230  is adapted to straddle a portion of said haptic  210 . The staple  230  is adapted to be manipulated from a relaxed state to a tensioned state whereupon it is released and and attaches to the iris. In the illustrated embodiment, the staple in the relaxed state is expanded. It is then compressed (with an insertion tool discussed hereinbelow), placed in overlying straddling relation to the respective haptic(s), and upon release, expands to substanitally return to its original state, thereby fixing the position of the optical implant thereon. It will be noted that the tensioned and relaxed states could be reversed with equal effacacy. As with the embodiment shown in FIGS. 9-14, the staple is dimensioned such that it penetrates a portion of, but less than the entire iris, preferably, approximately one-half the thickness of the iris. The reader will appreciate that the dimensions and degree of iris penetration will vary with the particular type of optical implant used. For example, in FIGS. 9 and 10, optical implants having a pair of vaulted loop-type haptics located on opposite sides of the optic is shown with staples. In FIGS. 11-12 an optical implant having four vaulted loop-type haptics is shown with staples. Further, the haptics are configured such that the optic is in spaced relation from the iris. In FIGS. 13-14 an optical implant with flexible curved haptics is shown with staples  230 . In this embodiment, the staple(s) could be located such that the intraocular lens expands and contracts with the dilation of the iris sphincter muscle. 
     The staples  230  employed in the above-noted embodiment are inserted using an insertion instrument generally indicated at  240  as illustrated in FIGS. 18 through 27. It will be noted that prior to insertion, the staple must be transported by the surgeon within the eye, and further, that once within the eye, is not susceptible to adjustment. Thus, the instrument, which is described in detail hereinbelow, is designed with safety features such that it is difficult to accidentally release the staple and further, once released, the staple automatically contrats and grippingly attaches to the iris. With the foregoing in mind, the instrument comprises a pair of manipulating rods or handles  242  having respective finger loops  244  at one end which assist the surgeon in one-handed operation during insertion of the instrument tip into the eye. The opposite ends of the respective handles divide into a U shaped bracket, which supports a block  246 . In the center of the block  246  is a hole defining an opening  248 . A finger  250  depends downward and inward and terminates in a gripping tab  252 . Also provided is a locking plate  254  which includes a U-shaped block having an elongate bore  256  therein which allows it to be placed in alignment with the other blocks  246  when pivot pin  258  is aligned therein. A rectangular plate  260  is attached to the underside of the block as best shown in FIG.  19 . The plate  260  establishes the limit of vertical travel staple  230  in the instrument. 
     In operation, the instrument handles are spread apart to spread the fingers  250  and locking plates  254 . The staple  230  is then inserted such that the arched mid-section abuts plate  260  and the legs are situated between opposing pairs of gripping tabs  252 . The handles are then moved together which causes the staple to be caught between locking plate  254 , gripping tabs  252  and plate  260 . Continued pressure causes the staples opening to become expanded. The instrument is then inserted in the eye such that the staples overlies in straddling relation the haptic. The manipulating rods are then moved apart from each other which causes the locking plate  254  to move outward, which in turn permits the staple  230  to slide out from between the gripping fingers and to contract into the iris. 
     A third embodiment of the invention is illustrated in FIGS. 15 through 17. In that embodiment an optical means or implant  300  for producing a preselected optical effect on light entering the eye and adapted to be implanted in overlying relation to the iris  52  is employed. The implant  300  includes an anterior side  302  and a posterior side  304  and an outer peripheral edge  306 . A single or plurality of haptic means or haptics  308  are connected to the implant  300  such that at least one includes a hole defining an opening  310 . A fastening means  312  for fixing the position of the intraocular lens on the iris is provided. 
     The fastening means or fastener  312  is adapted to be inserted within the opening  310  and to expandingly grip the iris tissue. More specifically, the fastening means  312  comprises a shaft having a top end  314  and a bottom end  316 . Located at the bottom end  316  is a flexible barb  318  and the top end  314  has a diameter that is greater than the diameter of opening  310 . As illustrated in FIG. 17, the barbs are arranged to point outwardly when relaxed. 
     In operation, the implant  300  is centered over the iris. Then fastener  312  is gripped with forceps (not shown) such that the barbs  318  are compressed. The fastener  312  is then guided into the opening  310  and downward pressure is then gently exerted to push the staple  312  through opening  310 . As the barbs exit the opening on the anterior side  304 , they contact the iris tissue and begin to expand. When the top end  314  contacts the upper surface of the haptic  308 , the barbs penetrate the iris (approximately one-half of the thickness of the iris in the illustrated embodiment) and the position of the implant  300  is fixed in the eye. The foregoing procedure is repeated for each haptic and the number of fasteners employed will depend on the geometry of the specific implant  300  chosen by the surgeon. 
     The present invention, of course may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present invention is therefor, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and range of the appended claims are intended to be embraced therein.