Abstract:
An accommodating intraocular lens having an optic and portions extending from the optic radially outwards preferably with fixation devices at their distal ends, the optic designed such that it has a sharp posterior edge for 360 degrees of its perimeter and the lens designed such that the optic can move forward and backwards with constriction and relaxation of the ciliary muscle.

Description:
[0001]     The present application is a regular utility application claiming priority from U.S. provisional patent application Ser. No. 60/527,340 filed Dec. 4, 2003, and related application Ser. No. 10/454,280, filed Jun. 3, 2003, which is a continuation of Ser. No. 10/057,691, filed on Jan. 24, 2002, which is a division of application Ser. No. 08/858,978, filed on May 20, 1997, now U.S. Pat. No. 6,387,126, which is a continuation-in-part of application Ser. No. 08/388,735, filed on Feb. 5, 1995, now abandoned, the disclosures of which are incorporated by reference. 
     
    
     BACKGROUND  
       [0002]     Intraocular lenses have for many years had a design of a single optic with loops attached to the optic to center the lens and fixate it in the empty capsular bag of the human lens. In the mid &#39;80s silicone plate lenses were introduced, which were 10.5 mm in length and had a 6 mm optic. These lenses did not fixate well in the capsular bag, but resided in pockets between the fused anterior and posterior capsules. The first foldable lenses were all made of silicone.  
         [0003]     In the mid 1990s an acrylic material was introduced as the optic of lenses. The acrylic lens had a biconvex optic with a straight edge into which was inserted loops to center the lens in the eye and fixate it within the capsular bag. Claims were made that the material of this lens significantly reduced posterior capsular opacification. It later became apparent that the property of the lens that reduced posterior capsular opacification was not necessarily related to the material, but to the relatively sharp or “square edge” on the posterior surface of the optic. The optic, when it is sealed within the capsular bag, presented a square sharp edge to the posterior capsule, which is tightly pulled against it during the period of fibrosis, preventing the ectodermal cells from growing across the posterior capsule behind the optic. A barrier was formed which successfully reduced the posterior capsular opacification rate. Silicone optic lenses were manufactured with a similar so-called straight edge in the posterior surface of the optic. Studies were done and the instance of posterior capsular opacification was found to be the same in the silicone lenses as in the acrylic lenses; therefore the material was not the cause of the reduction of the reduction in posterior capsular opacification. The sharp edge of the optic where the posterior optic surface joined the edge of the lens was the prime reason for the reduced incidence of posterior capsule opacification.  
         [0004]     Recently accommodating intraocular lenses have been introduced to the market, which are modified plate haptic lenses and, like the standard silicone plate haptic lenses, have no clear demarcation between the junction of the plate with the optic&#39;s posterior surface. A plate haptic lens may be defined as an intraocular lens having two or more plate haptics where combined junctions with the optic represent one quarter or more of the circumference of the optic.  
       SUMMARY OF THE INVENTION  
       [0005]     The objective of this invention is to provide an optic in a plate lens design with a 360 degree sharp edge. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1   a  is a perspective view of a simple plate lens without hinges, illustrating the sharp edge on the posterior surface of the optic.  
         [0007]      FIG. 1   b  is a plan view of the lens of  FIG. 1   a , looking at it from the posterior surface with the sharp edge surrounding the optic.  
         [0008]      FIG. 2  shows a similar lens with T-shaped haptics and hinges across the plates adjacent to the optic.  
         [0009]      FIG. 3  shows a T-shaped lens where T projections are made of flexible material, such as the plate, with fixation devices at the terminations.  
         [0010]      FIG. 4  shows detail of the fixation device.  
         [0011]      FIG. 5   a  diagrammatically illustrates how the sharp 360 degree edge is formed.  
         [0012]      FIG. 5   b  shows a side view of the preferred posterior optic surface of all the lenses shown in Figures.  
         [0013]      FIG. 6  is a T-shaped variation of an accommodating lens demonstrating the flexibility of the loops, which is also shown in  FIG. 7 .  
         [0014]      FIG. 7  shows the flexibility of the loops relative to the optic of the lens of  FIG. 6 .  
         [0015]      FIG. 8  is an elevational view of a lens having a flexible optic and flexible plate haptics extending oppositely from the optic, the plate haptics having grooves or hinges across their plates adjacent to the optic.  
         [0016]      FIG. 9  is a cross section of the lens of  FIG. 8  showing the 360 degree sharp edge on the posterior surface of the optic.  
         [0017]      FIG. 10  is another version of the lens with the fixation devices being on the end of the plates comprising projections on the anterior, posterior, or both surfaces at the distal ends of the plates.  
         [0018]      FIG. 11  is a cross section of the lens of  FIG. 10  showing the sharp 360 degree edge on the posterior surface of the optic.  
         [0019]      FIG. 12  is another version with different fixation devices extending from the corners of each of the plates.  
         [0020]      FIG. 13  is an elevational view of yet another version of the accommodating lens with plates fixated to the optic and flexible loops of a different material extending from the ends of the plates.  
         [0021]      FIG. 14  is similar to  FIG. 13  except that there are no hinges across the plates as shown in  FIG. 13 , the haptics being sufficiently resilient such that they do not require hinges.  
         [0022]      FIG. 15  shows a lens with multiple plate haptics and T-shaped fixation devices at the peripheral ends.  
         [0023]      FIG. 16  is another variation of a hybrid lens with two half-discs and fixation devices at their periphery.  
         [0024]      FIG. 17  is a complete disc surrounding the optic with fixation and centration devices attached to the rim of the disc.  
         [0025]      FIG. 18  shows an alternative embodiment. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0026]     The purpose of the invention is to provide a sharp edge for 360 degrees on the posterior surface of the optic of a haptic, probably a plate-haptic, intraocular lens. Standard plate or other lenses can have a sharp edge through the section of the periphery of the optic that is not adjacent to the plate. The essence of this invention is that the lens optic has a sharp edge for 360 degrees, thus preventing or reducing the opacification of the posterior capsule after implantation of the lens into the capsular bag of the human eye. The cross section of the lens in  FIGS. 5   b ,  9  and  11  shows flexible plate haptics  2  adjacent to an optic  4 , and shows hinges  3  formed by grooves across the haptics on the anterior side. The anterior surface  21  of the optic  4  opposes the posterior surface  20 . The sharp edge  12  is clearly shown on the posterior surface and extends for 360 degrees. The lens is an accommodating lens such that the optic is moveable anteriorly and posteriorly relative to the outer ends of the haptics, the lens being designed to produce a maximal movement of the optic relative to the outer ends of the plates.  FIG. 5   a  diagrammatically shows how the 360 degree edge is formed.  
         [0027]     The lens comprises extending portions which may be plates with either integrally formed loops of the same material as the extended portions or with T-shaped loops of a different material, such as polyimide, prolene, or PMMA. The loops are flexible such that the tip-to-tip diameter may be 11 to 13 mm outside the radius of the capsular bag, but the loops flex down toward the optic when placed in the capsular bag, thereby ensuring excellent centration of the optic and fixation of the lens. The loops may be sized to be independent of contact or be in contact with the ciliary muscle through the capsular bag wall.  
         [0028]     Referring to  FIGS. 6 and 7  of the drawings, a preferred form of the intraocular lens  1  is shown wherein the lens comprises two components, namely a flexible optic  4  and plate haptics  2  which are capable of multiple flexions without damage. These two Figures show a plate haptic design with T-shaped flexible loops  5  extending from the corners of each of the plates  2 . Collars  5   a  also can be provided if desired at the outer ends of the loops  5 . Hinges  3  facilitate the anterior and posterior movement of the optic relative to the outer ends of the plates. One or more plate haptics  2  extend distally from opposite sides of the optic. The haptics are plate haptics, preferably having arcuate outer edges. Loops  5  when unrestrained, are somewhat less curved in configuration than shown in  FIG. 6 . The lens, including the optic  4 , haptics  2 , and loops  5  is preferably formed of flexible material such as silicone, acrylic, or hydragel, preferably of a material that does not fracture with time. The fixation devices may be of a different material than the plate, such as polyimide, prolene, or PMMA and are molded into the distal ends of the plate as is described later with reference to  FIGS. 2 through 4 .  
         [0029]     As is well known in the art, an intraocular lens such as that of the various Figures is implanted in the capsular bag of the eye after removal of the natural lens. The lens is inserted into the capsular bag by a generally circular opening cut in the anterior capsular bag of the human lens and through a small opening on the cornea or sclera. The outer ends of the haptics, having loops on their distal edges, are positioned in the cul-de-sac of the bag. The loops  5  are in close proximity with the bag cul-de-sac, the loops being deflected from the configuration shown centrally toward the optic as seen in  FIG. 6  and shown in dashed lines in  FIG. 7 . The loops are shown in their central position in  FIG. 7 . Knobs  22  can be provided on the outer end portions of the loops (note, e.g.,  FIGS. 2 through 4 ,  6 ,  10  through  12 , and  15  through  17 ) for improved securement in the capsular bag or cul-de-sac by engagement with fibrosis which develops in the capsular bag following the surgical removal of the central portion of the anterior capsular bag. The end of the loops containing the knobs may be either integrally formed from the same material as the plates or may be of separate material such as polyimide, prolene, or PMMA  5 , as shown in  FIGS. 2 through 4 . The loop  7  in  FIG. 2  is integrally formed with the plate  3 , whereas loop  8  is of a separate material and is secured to the haptic  2  at  6 . The junction in  FIG. 2  of the posterior surface of the optic  4  to the edge of the lens is a sharp junction  12  designed to reduce the migration of cells across the posterior capsule of the lens postoperatively and thereby reduce the incidence of posterior capsular opacification and the necessity of YAG posterior capsulotomy. The anterior surface of the lens  21  is closer to the groove or hinge  3  than the posterior surface  20 .  
         [0030]     The loops  8  formed of a separate material in  FIG. 4  are molded into the terminal portions of the plates  2  such that the flexible material of the loop can extend by elasticity along the internal fixation member  10  of the loop  8 . The plates  2  may have a groove or hinge number  3  across its surface adjacent to the optic. This facilitates the anterior and posterior movement of the optic relative to the outer ends of the haptics. A hard knob  22  on the end of the loops  7  or  8  is designed to fixate the loops in the capsular bag and at the same time allow the elastic loop to stretch along its length as the optic of the lens moves backwards and forwards and the plate haptics move or slide within a pocket formed between the fusion of the anterior and posterior capsules of the capsular bag.  
         [0031]     Turning to other embodiments,  FIG. 8  shows a simple plate lens design with hinges  3  across the plates.  FIG. 9  shows a plate lens with one or more fixation devices  22  on the distal ends of the plates projecting from either the anterior or posterior or both sides of the plates.  FIGS. 9 and 11  show a cross section of the respective lenses of  FIGS. 8 and 10 .  FIG. 12  shows another lens where the fixation devices are knobs  22  on the ends of small protrusions  22   a  at the corners of each of the plate haptics.  FIG. 13  shows another accommodating lens whereby the fixation and centration device is formed of loops  7   a  that are molded into the plate haptic. Holes  7   b  also can be provided in the ends of the loops. In  FIG. 14  there is no groove across the plate, the plate being sufficiently flexible that a hinge mechanism is not required.  
         [0032]      FIG. 15  shows another variation of the lens with four plates and four hinges, and a T-section at the end of each plate with knobs  22  on the ends for fixation in the eye. There also can be notches  17  in the plates to further enhance the fixation of the distal part of the plate into the eye.  FIG. 16  shows a disc variation of a lens with two half plates with loops  5  and a knob  22  at the end for fixation and centration of the lens within the eye.  FIG. 17  shows another variation of the circular plate design with one or more centration and fixation devices about the periphery of the flexible plate with a central optic.  
         [0033]      FIG. 18  illustrates an alternative embodiment wherein the extending portions or haptics are in the form of thin members  2 , extending from the optic  4 . Centration/fixation loops  5  can be added to both outer ends or not added as desired, and likewise hinges  3  as shown can be provided on both sets of haptics or omitted from both as desired. Furthermore, knobs  22  can be provided at the ends of loops  5 , or omitted.  
         [0034]     Many changes, modifications, variations, and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification together with the accompanying drawings and claims. All such changes, modifications, variations, and other uses of the applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is limited only by the claims which follow.