Abstract:
An intraocular lens arrangement having positive or negative lens with a frame that extends from the lens to provide diametrically opposed upper and lower frame sections. A first lens linkage has its first end attached to the upper frame section with at least two points of contact with the upper frame section. A second lens linkage has its first end attached to the lower frame section with at least two points of contact with the lower frame section. A second end of said first lens linkage and a second end of the second lens linkage are attached to a sulcus or zonule member to provide relatively large movement of the lens with a small movement of the ciliary muscle during accomodation response of the eye, and wherein the movements during the accommodation response are along the optical axis of the eye and are controlled in order to improve the image on the retina of objects viewed by the eye over a wide range of distances. The lens is preferably a positive lens with the appropriate frame. The haptics that connect the frame to the sulcus member is at least two pairs of haptics or alternatively a pair of single curved haptics that each have a sulcus connecting member. The intraocular lens cand contain a positive lens as note above along with a negative lens.

Description:
[0001]     This is a continuation-in-part of our U.S. application Ser. No. 10/738,271 filed Dec. 17, 2003 which is based on PCT application PCT/US02/19534 filed Jun. 21, 2002 which claims priority of our U.S. provisional application 60/299,757 filed Jun. 22, 2001. 
     
    
     FIELD OF THE INVENTION  
       [0002]     This invention relates to intraocular lenses and more particularly to intraocular lenses that have a frame extending from the lens and haptics connected to the frame on at least two upper and two lower points on the frame and connected to a sulcus or zonule member to move the lens along an optical axis in response to the movement of the eye ciliary sulcus or zonules and which may be implanted in the eye.  
       BACKGROUND  
       [0003]     The lens within the human eye has the capability of changing shape and thereby focus so that objects both far and near can be registered sharply on the retina. This ability to change focus is known as accommodation. With age, the lens gradually loses its range of accommodation. The human lens not only loses accommodative range with aging, but also transparency. When the lens loses a significant amount of transparency (thus producing a blurry image on the retina), it is said that the lens is cataractous or has become a cataract. Treatment for a cataract requires the surgical removal of the cataract and the placing of a man made synthetic lens (intraocular lens or IOL) in the eye. The earlier IOL&#39;s had a fixed focus and thus had no accommodative function.  
         [0004]     However, in time a number of IOL&#39;s were designed in multifocal form. Different zones of a multifocal IOL have different dioptric powers. With such multifocal IOL&#39;s, light from objects, only within a specific range of viewing distances, passing through a particular zone will form sharply focused images on the retina. On the other hand, if an object is outside this range, its image formed by the zone under consideration will be blurry. Multifocal IOL&#39;s typically have two or more zones, each designed for a specific viewing distance. A consequence of this design approach is that the imagery of multifocal IOL&#39;s is never very sharp. The success of multifocal IOL&#39;s depends on the visual processing system of the patient&#39;s eye and brain that tends to pay attention to the light most sharply focused on the retina, and tends to ignore the light formed diffusely on the retina.  
         [0005]     These were followed by IOL&#39;s that could move back and forth via ciliary muscle contraction and thus focus objects from different distances onto the retina. However, these IOL&#39;s have limited range of movement and thus a limited accommodative range. Another form of IOL is made of an elastomer filled flexible balloon which is placed within the emptied lens capsule and alters lens shape under the influence of the ciliary muscle contraction. Another accommodative IOL design is comprised of two positive lens elements (i.e. two plano-convex lenses) connected by two flexible hinges. The lens components are spread or come together in response to ciliary muscle contraction.  
         [0006]     In our invention, we have an intraocular lens that preferably has an integral frame that enclosed at least 25% of the outer circumference of the lens i.e. 90° out of 360° of a circular lens.  
         [0007]     Also we have an accommodative IOL that can be used alone or can be a combination of a positive lens (i.e. lens is thicker at center than at edge), and a negative lens (i.e. lens is thinner at center than at edge). Also, our IOL can alter dioptric power if placed in either of two intra ocular locations: a) within the capsular bag, or b) placed within the ciliary sulcus. In both locations, the contraction of the ciliary muscle alters the position of the lens.  
       SUMMARY OF INVENTION  
       [0000]     The present invention provides:  
         [0008]     1. An intraocular lens having a lens, a frame extending from the lens, a lens linkage attached to the frame using at least four points of connection (two upper and two lower connections) on the frame and attached to a sulcus or zonule member to provide relatively large movement of the lens with a small movement of the ciliary muscle.  
         [0009]     2. An intraocular lens having a lens, a first linkage having a first end connected to at least two contact points on the lower portion of the lens frame and a second end connected to an upper portion of the ciliary sulcus or zonule member, and a second linkage having its first end connected to at least two contact points on the upper portion of the lens frame and its second end to be connected to a lower portion of the ciliary sulcus or zonule member.  
         [0010]     3. Intra ocular lenses as noted in above 1-2 wherein the lens is a positive lens and the intraocular lens is implanted in or outside of the lens capsule or capsular bag.  
         [0011]     4. An intraocular lens as noted in above 1-3 wherein the intraocular lens includes the positive lens of above 1-2 and a negative lens.  
         [0012]     One embodiment of the present invention is to provide an intra ocular lens having a lens, a frame enclosing at least 25% of the outer circumference of the lens i.e. 90° out of 360° of a circular lens with diametrically opposed upper and lower frame sections. The frame is preferably integral with the lens and the frame has connected thereto linkages hereinafter referred to as haptics that extend from the frame to a ciliary sulcus or zonule member. There are at least two haptics. One haptic has one end connected to a first frame portion with the one end having at least two contact points with the first frame portion. The other haptic has one end connected to a second frame portion with the one end having at least two contact points with the second frame portion. The first frame portion is diametrically opposite the second frame portion.  
         [0013]     A second embodiment of the present invention is to provide an eye intra ocular lens that has a negative lens and a positive lens that are axially separated and said intra ocular lens is formed inside the eye as part of an implantation of the negative and positive lenses in an eye or outside of the eye by connecting the negative and positive lenses prior to implantation into the eye such that the positive lens will move relative to the negative lens and the positive lens has the lens frame as described above and hereinafter.  
         [0014]     For the purpose of promoting an understanding of the principles of the invention, references will be made to the embodiment illustrated in the drawings. Specific language will also be used to describe the same. It will, nevertheless, be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention illustrated herein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
     
    
     DESCRIPTION OF DRAWINGS  
       [0015]      FIG. 1  is a front plane view of an intraocular lens according to the present invention;  
         [0016]      FIG. 2  is a left side view of the lens of  FIG. 1 ;  
         [0017]      FIG. 3  is a perspective view of the lens of  FIG. 1 ;  
         [0018]      FIG. 4  is a front plane view of another intraocular lens according to the present invention;  
         [0019]      FIG. 5  is a perspective view of the lens of  FIG. 4 ;  
         [0020]      FIG. 6  is a rear plane view of another intraocular lens according to the present invention;  
         [0021]      FIG. 7  is a perspective view of another intraocular lens according to the present invention; and  
         [0022]      FIG. 8  illustrates a dual lens system according to the present invention.  
         [0023]      FIG. 9  illustrates the IOL of  FIG. 8  connected to the ciliary sulcus.  
         [0024]      FIG. 10  illustrates the IOL of  FIG. 8  within a lens capsule 
     
    
     DETAILED DESCRIPTION OF INVENTION  
       [0025]     Our invention relates to an intraocular lens (IOL), having either a positive lens and/or a negative lens. When two lenses (positive and negative lenses) are to be used in one eye, the positional order of the lenses in the eye can be either with the positive lens more anterior or the reverse, or with the negative lens more anterior or the reverse. Each single or dual lens system may be placed either outside or within the capsular bag. The two lens system may or may not have the two lenses mechanically linked to one another by tabs and strut-like linkages (haptics) attached to the two lenses. During cataract surgery and IOL implantation, the positive and/or negative lenses may be inserted intra ocularly either one at a time (if the components are not mechanically linked to one another), or both at the same time (if the components are mechanically linked to one another). The linkages serve to hold the positive and negative lenses in place, as well as serve to adjust and control the distance separating the two lenses when powered by ciliary muscle contraction. It is the separation between the lenses that accounts for the change in IOL power (i.e. accommodation).  
         [0026]     The lenses are located preferably with a common axis which is also common with the optical axis of the eye (coaxial configuration). This coaxial configuration is maintained during the change in separation of the lens elements which causes the eye&#39;s accommodative response. The positive-negative lens configuration provides a greater change of dioptric power with change in separation distance than any other configuration such as a positive-positive or a singlet positive configuration.  
         [0027]     Our intraocular lens has a linkage that provides axial movement of the lens by connecting the haptics to a lens frame as hereinafter described in detail. Our linkage can be used on either or both the negative or positive lens when a dual lens is used and it is preferably used on the positive lens.  
         [0028]     The positive and negative lenses generally will have spherical surfaces; however, since astigmatic and other aspherical-shaped singlet IOL&#39;s (both symmetric and asymmetric with respect to their optical axes) now are manufactured for implantation in the eye, the positive and negative lenses may also have these more general surface shapes. Fresnel-type IOL lenses also are used in cataract surgery. These lenses generally have a succession of stepped-annular zones or facets which serve to minimize a Fresnel lens&#39;s thickness while maximizing it power. Fresnel-type positive and negative lenses are suitable lens components for use in our invention. Also, diffractive lens configurations are sometimes used (i.e., diffractive lenses or lenses with one surface diffractive and the other surface refractive.  
         [0029]     Generally, a person is not reading and is looking at objects more than two feet away. In that condition, the ciliary muscle is relaxed and the eye is focused on a distant object. When a two lens IOL is used, as shown in  FIGS. 8-10 , the positive lens and negative lens are brought together with a slight space there between. The spacing is necessary to prevent the two lenses from adhering to each other. Our co pending U.S. Application sets forth the reason why the IOL spacing is larger when the eye&#39;s focus changes from viewing a distant object to viewing a nearby object and those are incorporated in this application.  
         [0030]     The preferred manner of correcting a patient&#39;s vision using a dual lens in one eye is to open the eye&#39;s lens capsule or capsule bag, remove the eye lens and first insert the desired positive or negative lens in the lens capsule or capsule bag. Then the other lens is inserted into the lens capsule or capsule bag. The positive lens and negative lenses are connected to each other such that when the ciliary muscle contracts, the two lenses axially separate from each other and when the ciliary muscle relaxes, the two lenses axially move towards each other. In our invention generally, only one of the lenses (preferably the positive lens) moves and the other lens (the negative lens) does not move or moves substantially less and both lenses remain substantially coaxial with each other. One manner of connecting the two lenses to each other would be to connect them both independently to the ciliary muscle and the ciliary muscle zonules. Another method would be to attach the linkages of the positive lens to the linkages of the negative lens. The attachment could be any suitable attachment that would allow the lenses to move away from the each other when the ciliary muscle contracts and towards each other when the ciliary muscle relaxes.  
         [0031]     Examples of our IOL having a singlet positive lens is hereinafter described when referring to  FIGS. 1-7   FIGS. 1-3  show a positive lens  20  having a circular frame  21  integral therewith and radially extending from the outer circumference of the lens. A pair of upper haptics  22  and  23  have first ends  22   a ,  23   a  respectively connected to the upper portion of the frame  21  and the ends are spaced at least 15° apart. A pair of lower haptics  24  and  26  have first ends  24   a ,  26   a  respectively connected to the lower portion of the frame  21  and the ends  24   a  and  26   a  are spaced at least 15° apart. A sulcus or zonule connecting ring  27  is axially spaced from the lens  20  and is sized to be connected to the ciliary sulcus or to be placed in the eye capsule and connected to to the ciliary muscle through the respective zonules.  
         [0032]     The point of connection of the haptic ends  22   a ,  23   a ,  24   a  and  26   a  all lie in the same plane which is vertical to the lens axis  29 . The point of connection for  22   a  is diagonal to the point of connection for  24   a . The point of connection for  23   a  is diagonal to the point of connection for  26   a.    
         [0033]     The frame  21  preferably has a plurality of holes  28  therein to reduce the weight of the IOL and also to permit flexibility of the IOL. The lens  20  shown is a positive lens but as stated above if it is desired this may be a negative lens. The circular frame  21  preferably has a convex shape. The haptics  22 ,  23 ,  24 , and  26  are considered reverse toggle haptics.  
         [0034]     The second end  22   b  of haptic  22  and the second end  23   b  of haptic  23  are connected to the lower portion of the ring  27  on opposite sides of the optical axis  29  than their respective upper ends  22   a  and  23   a . The second end  24   b  of haptic  24  and the second end  26   b  of haptic  26  are connected to the upper portion of the ring  27  on opposite sides of the optical axis  29  than their respective upper ends  24   a  and  26   a . As hereinafter set forth, when the ciliary muscle causes the ring to compress, the lens  20  moves away from the ring  27 .  
         [0035]     Referring to  FIGS. 4 and 5  we show an alternative structure for our IOL. The IOL in  FIGS. 4 and 5  have a positive lens  30  with a frame  31  integrally extending from its upper and lower circumference encompassing more than 90° of the upper portion and more than 90° of the lower portion. A center line passing through the center of the lens  30  and contacting the any two extremities of the frame has a length less than the diameter length of the sulcus or zonule connecting ring  37 . Thus like the embodiment of  FIGS. 1-3 , the lens frame is entirely within the ring. The lens frame has a pair of spaced upper haptics  32  and  33 . Haptic  32  has a first end  32   a  and haptic  33  has a first end  33   a . The first ends  32   a  and  33   a  are spaced apart and hinged to the upper portion of the frame  31  adjacent the opposite sides  35   a  and  35   b  of the frame upper portion and the frame end  35   c . The points of connections on the frame of ends  32   a  and  33   a  are spaced at least 15° apart when measured by a radius line from the center of the lens  30  to the points of connection of ends  32   a  and  33   a . The second end  32   b  of haptic  32  and the second end  33   b  of haptic  33  are connected to the lower portion of the ring  37  on opposite sides of the lens axis  29 .  
         [0036]     The frame has a pair of spaced lower haptics  34  and  36 . Haptic  34  has a first end  34   a  and haptic  36  has a first end  36   a . The first ends  34   a  and  36   a  are spaced apart and hinged to the lower portion of the frame  31  adjacent the opposite sides  35   d  and  35   e  of the frame lower portion and the frame lower end  35   f . These points of connection on the frame for the ends  34   a  and  36   a  are spaced at least 15° apart when measured by a radius line from the center of the lens  30  to the points of connection on the frame for ends  34   a  and  36   a . The second end  34   b  of haptic  34  and the second end  36   b  of haptic  36  are connected to the lower portion of the ring  37  on opposite sides of the optical axis  29 .&lt; &gt;The sulcus or zonule connecting ring  27  is axially spaced from the lens  20  and is sized to be connected to the sulcus or to be placed in the eye capsule and connected to the zonules.  
         [0037]     The lens  30  shown is a positive lens but as stated above if it is desired this may be a negative lens. The rectangular frame  31  preferably has a convex shape.  
         [0038]     Referring to  FIG. 6 , the IOL therein has the same general structure of the IOL of  FIG. 1  and therefore we have used the same numerals to depict the same items. The only difference between the two structures is that the sulcus or zonule connecting member has a different shape. The connecting member  27  is a ring and the connecting member for  FIG. 6  are two arcs  41   a  and  41   b . Haptic ends  24   b ,  26   b  are connected to the opposite ends of the arc  41   a . Haptic ends  22   b ,  23   b  are connected to the opposite ends of the arc  41   b.    
         [0039]     Referring to  FIG. 7 , there is shown another alternative IOL. The IOL in these Figs have a positive lens  40  with an upper frame  42  and lower frame  43  integrally extending from its upper and lower circumference encompassing more than 90° of the upper portion of lens  40  and more than 90° of the lower portion of lens  40 . The upper end  42   a  of the upper frame  42  forms a cylindrical opening and lower end  43   a  of the lower frame  43  forms a cylindrical opening. A curved haptic  44  has one end  44   b  passing through the upper frame opening so that the haptic end freely rotates or pivots in the opening. The elongated haptic end  44   b  contacts more than one inner surface point of the frame opening  42   a  to provide stability and even movement of the lens  40  along the optical axis. The other end  44   a  of the haptic  44  has a curved surface such that the end  44   a  curves below the lower frame end  43   a . and its radius conforms to curvature of the lower sulcus. A second curved haptic  46  has one end  46   b  passing through the lower frame opening so that the haptic end  46   b  freely rotates or pivots in the opening. The elongated haptic end  46   b contacts more than one inner surface point of the frame opening  43   a  to provide stability and even movement of the lens  40  along the optical axis. The other end  46   a  of the haptic  46  has a curved surface that curves above the upper frame end  42   a . and its radius conforms to curvature of the upper sulcus. Thus when the IOL of  FIG. 7  is inserted in the eye, it is inserted with the haptic ends contacting the sulcus of the eye so that when the sulcus contracts the lens  40  moves in the direction of the arrow in  FIG. 7 . When the sulcus relaxes, the lens moves in the opposite direction of the arrow. Alternatively, when this IOL is placed in the eye capsule, it is inserted so that the haptic ends are connected to the inner walls of the capsule so that when the sulcus muscle contracts, the zonules become lax and the lens  40  moves in the direction of the arrow in  FIG. 7 .  
         [0040]     The haptic ends  43   a  and  44   a  can if desired be maintained in their respective cylindrical openings by appropriate means to prevent them from exiting the cylinder i.e. appropriate washers. The haptics may have a helical configuration or partial helical configuration as long as one end is above the lens and the other end is below the lens or vice versa and as long as the haptic end connected to the frame has more than one i.e. at least two, contact point with the frame.  
         [0041]      FIG. 8  shows one possible configuration of a way in which a positive lens  20  may be coupled mechanically to a negative lens  50 , where both lenses comprise an assembled accommodating dual IOL  51 . The positive lens IOL is the same as that illustrated in  FIGS. 1-3 . Of course the other positive lens IOLs note in  FIGS. 4-7  may be used instead. The negative lens  50  is connected to the ring  27  by haptics  52  and  53 . The haptics  22 ,  23 ,  24 ,  26 ,  52 , and  53  are sized to provide adequate leverage to cause the positive lens  20  and the negative lens  50  to separate when the ciliary muscle contracts. The haptics are generally made of the same polymer material as their respective lens and are preferably integral with their respective lenses. They, of course, may be made of separate materials and appropriately affixed to their respective lenses. The linkages are sufficiently rigid such that a force directed towards the center of the eye by a contracting ciliary muscle causes the lenses  20  and  50  to separate from each other as shown in  FIGS. 9 and 10 . Each linkage  52  and  53  is semi-rigid straight (or reasonably straight) and has flexure joints (one at the apex of the haptics  52  and  53 , and one each linking arm is attached to the lens  50 . The configuration shown in  FIG. 8  will cause the lenses to separate when a compressive force is applied to the ring  27 .  
         [0042]     Although the joining of the linkages is preferred, the negative lens haptics  52  and  53  may be separate and not attached. However, they will extend at an angle to the optical axis so that at least the positive lens can move along the optical axis.  
         [0043]     Although the hinge configuration in  FIG. 8  shows that the haptics have approximately the same length, haptics having different lengths and different angles from those shown in  FIG. 8 . Another hinge configuration for the negative lens may be used to move the two lenses during accommodation such as a more general “lambda” shape (i.e. the Greek letter λ) or, perhaps, a mirror-image X shape. Within the practice of mechanical engineering and design, it is obvious to those skill in those fields that there are many other hinge configurations that will result in constraining the movements of the two lenses appropriately in order to achieve the benefits of our invention.  
         [0044]     Although  FIG. 8  shows the positive and negative lens components of the IOL coupled by mechanical linking arms, two independent (i.e. not linked) lenses conceivably can be implanted in sequence by skilled surgeons at precise locations in either the capsular bag or the ciliary sulcus to achieve good focusing during accommodation.  
         [0045]      FIG. 9  (left) shows an accommodating dual IOL  51 , which is a mechanically linked positive-negative lens pair, implanted in the ciliary sulcus  62  behind the eye&#39;s cornea  63  and in front of the lens capsule  64  with the ciliary muscle  65  relaxed (eye focused at distant object). The dual IOL  51  is mechanically linked after or before being implanted. In this instance lens separation  66  is relatively small. The zonules  67  support the lens capsule  61  from which the cataract has been removed.  
         [0046]      FIG. 9  (right) shows the same accommodating dual IOL  51  and how the lens separation  68  increases during accommodation when the ciliary muscle tightens causing the sulcus  62  to constrict. Also shown is how the lens capsule  64  and the supporting zonules  67  tend to move to the right during ciliary muscle contraction.  
         [0047]      FIG. 10  (left) shows an accommodating dual IOL  51 , which is a mechanically linked positive-negative lens pair, implanted in the lens capsule  64  behind the eye&#39;s cornea  63  with the ciliary muscle  65  relaxed (eye focused at distant object). IOL  51  is mechanically linked after or before implantation. In this instance, lens separation  69  is relatively small, since the zonules  67  which are taught exert an outward tension at the edges of the lens capsule  64  where the dual IOL&#39;s flexible hinged apex is attached.  
         [0048]      FIG. 10  (right) shows the same accommodating IOL  51  implanted in the lens capsule  64  behind the eye&#39;s cornea  63 , and how the lens separation  70  increases during accommodation when the ciliary muscle  65  tightens causing lax zonules  67  which exert reduced tension at the edges of lens capsule  31  where the IOL&#39;s flexible hinged apex is attached.  
         [0049]     Our co-pending U.S. Application illustrates ray traces from a computerized lens design program (ZEMAX) which illustrate the movement required from different types of accommodating IOL models for a prescribed amount of accommodation. That and the calculations set forth therein are incorporated in this application by reference.  
         [0050]     Various features of the invention have been particularly shown and described in connection with the illustrated embodiment of the invention, however, it must be understood that these particular arrangements merely illustrate, and that the invention is to be given its fullest interpretation within the terms of the appended claims.