Accommodative intraocular lens

#This invention relates generally to the field of intraocular lenses (IOL) and, more particularly, to accommodative IOLs.

#The human eye in its simplest terms functions to provide vision by transmitting light through a clear outer portion called the cornea, and focusing the image by way of a crystalline lens onto a retina. The quality of the focused image depends on many factors including the size and shape of the eye, and the transparency of the cornea and the lens.

#When age or disease causes the lens to become less transparent, vision deteriorates because of the diminished light which can be transmitted to the retina. This deficiency in the lens of the eye is medically known as a cataract. An accepted treatment for this condition is surgical removal of the lens and replacement of the lens function by an artificial intraocular lens (IOL).

#FIG. 1 is an enlarged top plan view of the first optic of a first embodiment of the lens system of the present invention.

#FIG. 2 is an enlarged cross-sectional view of the first optic of a first embodiment of the lens system of the present invention taken at line 2—2 in FIG. 1.

#FIG. 3 is an enlarged top plan view of the second optic of a first embodiment of the lens system of the present invention.

#As best seen in FIGS. 1-5 and 10, lens system 10 of the present invention generally consists of posterior optic 12 and anterior optic 14. Optic 12 is preferably formed in any suitable overall diameter or length, for example, around 12 millimeters, for implantation in the posterior chamber. Optic 12 preferably is made from a soft, foldable material that is inherently resistive to the formation of PCO, such as a soft acrylic. Optic 14 preferable is made from a soft, foldable material such as a hydrogel, silicone or soft acrylic. Optic 12 may be any suitable power, but preferably has a negative power. Optic 14 may also be any suitable power but preferably has a positive power. The relative powers of optics 12 and 14 should be such that the axial movement of optic 14 toward or away from optic 12 should be sufficient to adjust the overall power of lens system 10 at least one diopter and preferably, at least three to four diopters, calculation of such powers of optics 12 and 14 being within the capabilities of one skilled in the art of designing ophthalmic lenses by, for example, using the following equations: P=P1+P2−T/n*P1P2  (1) δP=δT/n*P1P2  (2)

#As best seen in FIGS. 1 and 2, optic 12 is generally symmetrical about optical axis 22 and contains a pair of opposing clasps 16 that are shaped to stretch and fill equatorial region 210 of capsular bag 200. Clasps 16 contain sockets 18 generally defined by latch 20. As best seen in FIGS. 3-5, optic 14 contains a pair of haptics 24 that are connected to optic 14 by hinge regions 26 and contain locking pins 28 distally from hinge regions 26. As seen in FIG. 10, locking pins 28 are sized and shaped to fit within sockets 18 on optic 12, thereby holding optic 14 firmly within optic 12 while still permitting rotation of locking pins 28 within sockets 18. One skilled in the art will recognize that sockets 18 may be located on hinge regions 26 and that locking pins 28 may be located on optic 12. In order to insert locking pins 28 within sockets 18, sockets 18 may be spread apart slightly, thereby preloading haptics 24. Once implanted in an eye, as one skilled in the art will recognize, contraction of capsular bag 200 will cause clasps 16 to collapse slightly, thereby causing compression of optic 14. As optic 14 is compressed, hinge regions 26 allow optic 14 to vault anteriorly away from optic 12, with locking pins 28 pivoting within sockets 18. One skilled in the art will recognize that no specific feature needs to be used to form hinge regions 26 as haptics 24 may be formed from a material and/or in such a configuration that haptics naturally flex in the manner of a hinge.

#As best seen in FIGS. 6-9 and 11, lens system 110 of the present invention generally consisting of posterior optic 112 and anterior optic 114. Optic 112 is preferably formed in any suitable overall diameter or length, for example, around 12 millimeters, for implantation in the posterior chamber. Optic 112 preferably is made from a soft, foldable material that is inherently resistive to the formation of PCO, such as a soft acrylic. Optic 114 preferable is made from a soft, foldable material such as a hydrogel, silicone or soft acrylic. Optic 112 may be any suitable power, but preferably has a negative power. Optic 114 may also be any suitable power but preferably has a positive power. The relative powers of optics 112 and 114 should be such that the axial movement of optic 114 toward or away from optic 112 should be sufficient to adjust the overall power of lens system 10 at least one diopter and preferably, at least three to four diopters, calculation of such powers of optics 112 and 114 being within the capabilities of one skilled in the art. One skilled in the art will also recognize that the axial movement of optic 114 relative to optic 112 is greater in this embodiment as opposed to the embodiment illustrated in FIGS. 1-5 due to the longer length of haptic 124 versus haptic 24.