Field of the Invention

[0001] The present invention relates generally to the field of ophthalmic surgery, and more particularly, to an improved intraocular lens that is especially suited for implantation in a ruptured capsular bag in the human eye.

Background of the Invention And Technical Problems Posed By The Prior Art

[0002] When the eye becomes aged, diseased, or injured it may be necessary to remove the natural lens of the eye. Such removal is common for cataract surgery, in which a lens that has become clouded is removed. The removal of the natural lens of the eye may result in the loss or alteration of focused vision of a patient. Therefore, an artificial lens is necessary to restore the vision of the patient. Some eyes have an oblong, irregularly shaped cornea that causes astigmatism, or blurred vision due to a refractive error in the eye.

[0003] Such artificial lenses may be provided in eyeglasses, contact lenses, or a permanent implant known as an intraocular lens (hereinafter “IOL”). The typical IOL is an artificial, generally circular lens with one or more stabilizing projections, arms, or haptics extending from the lens. A special type of implant called a toric IOL may be used to correct for astigmatism in the eye. The toric IOL has a lens body with an astigmatic axis that must be aligned with the steep corneal meridian of the eye. To implant the IOL in the eye, art incision is made in the anterior portion of the eye, typically while maintaining positive pressure within the eye to prevent coilapse of the delicate structures of the eye. The IOL is generally placed into a folded configuration or otherwise reduced volume state within an injector housing or cartridge and then injected through a small cannula or lumen into the eye. The IOL may also be inserted into the eye in an unfolded configuration dependent upon the flexibility of the IOL material. In the case of an Injector, the Injector housing is elongate for being placed through the incision and into the patient's eye after the natural lens has been dismembered and aspirated, such as through phacoemulsification or laser generated surgery. A plunger is retained within the injector housing and is movable with respect to the housing. Movement of the plunger through the housing presses the IOL forward into the eye. The IOL, typically being resilient (with elastic memory), will subsequently expand to an uncompressed or deployed configuration upon entering the eye and exiting the injector. The haptics of the IOL serve to balance and center the IOL within the lens capsule of the patient. The IOL is typically made from biocompatible materials such as PMMA, silicone, hydrogel, or acrylic.

[0004] Typically, when the IOL is implanted in the capsular bag, the anterior portion of the lens capsule is typically opened by way of continuous curvilinear capsulorhexis ("CCC”) wherein the physician mechanically shears the anterior portion of the capsule to create a generally circular opening.

[0005] During the removal of the natural lens of the eye, a physician may note that the zonules, or supporting ligaments of the capsular bag which contains the lens, are weakened, deteriorated, or otherwise insufficient to provide adequate structural support to centralize the haptics of the IOL within the eye. Therefore, a capsular tension apparatus or ring may be required to exert an outward pressure on the capsular bag prior to implantation of the IOL. Such capsular tension rings (CTR) are typically generally round or C-shaped and can be provided in various diameters to accommodate variations in human capsular bag diameters. Capsular tension rings are typically formed from a biocompatibie implant materia! such as PMMA. Other materials are also useful, depending upon the configuration of the rings, and how well they maintain their shape, and the size of the intended capsule. Capsular tension rings may be inserted through an incision in the anterior portion of the eye or may be folded and injected into the Incision in a similar fashion as described above with respect to the IOL.

[0006] Today, IOL designs are subject to rotation upon removal of the viscoelastic, as well as post-operativeiy when the capsule contracts and moves the IOL from its intended implant axis, in the former case, the eye is still surgically open, so additional manipulation of the tens can easily be performed to put it back on axis. However, if the lens moves due to improper sizing or capsular shrinkage (which occurs in virtually ail eye surgery cases,) this also requires additional rotation. This is more complicated because the patient requires a re-operation to reposition the lens, and this subjects the patient to many surgical risks which include infections as well as intra-operative complications such as capsular tears, and other post-operative complications that follow such an event. The goal is to have a lens that stays where it is placed at the time of surgery.

[0007] The inventors have found that some prior art three-piece, circular IOLs, of the type having a pair of stabilizing haptics extending outwardly of a central lens body or optic (e,g,, as shown in F!G. 1), may not be well-suited for implantation in the case of a posterior capsule rupture. These prior art Ids, having an optic size of 6.0 mm or 6.5 mm, have been found to be undersized when inserted under the CCC edge (110 in FIG. 1) for capture of the optic. In the case of a ruptured posterior capsule, there a risk with these prior art lOLs of movement of the vitreous into the anterior chamber.

[0008] The inventors have developed an improved IOL for eliminating or minimizing one or more of the above-discussed problems.

Brief Summary of the invention

[0009] The inventors of the present invention have discovered an improved intraocular Sens construction which is desirably configured prevent or a least inhibit movement of vitreous into the anterior chamber of the eye in the event of a rupture in the posterior portion of the lens capsule or capsular bag.

[0010] in accordance with one broad form of the present invention, an intraocular lens comprises a central lens body having first and second, opposite anterior and posterior surfaces for providing vision correction for a patient. The central lens body defines a central axis extending between the posterior and anterior surfaces and has the form of a rhombus when viewed in a plane that is normal to the central axis. The lens further includes at least one stabilizing haptic extending from the central lens body. [0011] In a presently preferred form of the invention, the central lens body is substantially square when viewed in a plane that is normal to the central axis.

[0012] in another presently preferred form of the invention, the intraocular lens has a pair of haptics extending from the centra! lens body generally at diametrically opposed portions thereof, whereby each of the haptics has an arcuate, elongate configuration,

[0013] In one aspect of the present invention, the central lens body defines a first pair of generally paral!el opposite peripheral edges and a second pair of generally parallel opposite peripheral edges, whereby the haptics extend from only the second pair of generally parallel opposite peripheral edges. Preferably, the haptics include a portion embedded within, and extending along, the second pair of generally parallel opposite peripheral edges and project outwardly away from the centra! lens body at a central location of the peripheral edges,

[0014] In another broad form of the present invention, a method of implanting an intraocular lens in a human eye includes the steps of: obtaining the inventive intraocular lens of any described above having a centra! lens body in the form of a rhombus; performing a continuous curvilinear capsuiotomy of an anterior portion of a lens capsule to define a leading edge; removing a natural lens nucleus from the lens capsule; implanting the intraocular lens within the eye by tucking the centra! lens body beneath the leading edge of the anterior portion of the lens capsule to locate the central lens body within the lens capsule; and fixing the pair of haptics within the ciliary sulcus of the eye.

[0015] In one preferred form of the method, the step of implanting said intraocular lens within the eye further includes tucking four corner portions of the central lens body beneath the anterior portion of the eye.

[0016] In accordance with one aspect of the present invention, each of the haptics have an arcuate, elongate configuration in the deployed configuration. Brief Description of the Drawings

[0017] FIG. 1 is a top plan view of a prior art three piece, circular IOL shown in an implanted, deployed configuration in the eye;

[0018] FIG. 2 is a top plan view of a first illustrated embodiment of an IOL according to the present invention shown in an implanted, deployed configuration in the eye;

[0019] FIG. 3 is a diagrammatic side elevation view of the IOL illustrated in FIG. 2 shown in an implanted, deployed configuration in the eye;

[0020] FIG. 4 is a top elevation view of only the IOL illustrated in FIG. 2; and

[0021] FIG. 5 is a top elevation view of alternative embodiments of the optic of an

IOL according to the present invention.

Detailed Description of the Preferred Embodiments

[0022] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated,

[0023] In accordance with the present Invention, FIGS. 2-4 illustrate a first embodiment of an intraocular lens assembly 10, including a pair of elongate stabilizing arms or haptics 12 comprising a generally rhomboid shape, preferably square, centra! optic, or lens body 18.

[0024] With reference to FiG. 3, the lens body 18 includes first and second, opposite posterior 20 and anterior 22 surfaces, wherein at least one of said surfaces 20 and/or 22 may have an arcuate cross-sectional configuration for providing vision correction for a patient. The Sens body 18 defines a centra! axis 19 extending between the posterior surface 20 and the anterior surfaces 22,

[0025] With reference now to FiG. 4, the pair of haptics 12 extend from respective opposite sides of the central lens body 18, with each haptic having a distal or peripheral edge portion 23 engageable with the interior of the eye and an embedded portion 24 connected within the centra! lens body 18. The haptics 12 extend laterally away from the central lens body 18 at a central location on opposite sides of the central lens body 18. Preferably, the lens haptics 12 extend outwardly from the central part of the Sens body 18 with a concave portion facing an adjacent corner of the lens body 18,

[0026] The central lens body 18 is made from a biocompatible material such as a hydrophobic acrylic white the haptics are formed form a Polymethyl methacrylate (“PMMA”). The central lens body 18 may have one or more surfaces of a varying degree of convexity depending on the need for correction to the patient’s vision. The central lens body 18 could be a multifocal lens (e.g., 18A in FIG, 5), a toric lens (e.g,, 18B in FIG. 5) having an astigmatic axis that must be aligned with the steep comeal meridian, or a non-toric lens (e.g., 18C in FIG. 5).

[0027] With reference now to FIG. 4, the central lens body 18 defines a first pair of generally parallel opposite peripheral edges 30 and a second pair of generally parallel opposite peripheral edges 34 which together define the perimeter of the central lens body 18. The embedded portion 24 of each haptic 12 extends along, substantially parallel to, one of the pair of edges 34.

[0028] With reference to FIG. 3, and as will be discussed in greater detail hereinafter, the inventors have found that the generally rhomboid, and more preferably, square shaped optic, may be more suited for engaging with the leading edge 110 of the anterior portion of the lens capsule 100. after the CCC, to prevent or at least minimize the movement of the vitreous body (e.g., 140) into the anterior chamber of the eye In the case of a rupture 120 of the posterior capsule. The inventors have found that the square shaped optic may be more easily inserted under the anterior capsule CCC edge 110 for capture of the optic within the lens capsule 100, This may be due to the larger retained area (visible in FIG. 2} of the square central tens body 18 beneath the tens capsule leading edge 110 when implanted, as compared to prior art circular IOL designs, which allows for better fixation of the inventive lens 10. [0029] Subsequent to a procedure for the removal of the natural lens (e.g., phacoemulsification, femtosecond laser, etc.), the intraocular lens or lens assembly 10 is implanted in eye of the patient, in the deployed configuration (FIGS. 2 and 3), the optic or central Sens body 18 is located within the lens capsule 100, wherein the anterior side 22 of the lens body 18 is tucked under the leading edge of the anterior capsule 110 that has been created by the CCC technique. In this configuration, the pair of haptic elements 12 extend in the anterior direction into the sulcus of the eye for fixation. Furthermore, this configuration may cooperate with the eye to maintain the position of Sens, thereby enhancing the stabilization and centering of an implanted IOL 10 within the eye.

[0030] As can be seen in FIGS. 2 and 3, when the central lens body 18 is tucked under the leading edge of the anterior capsule 110, four corner portions 130 of the central lens body 18 are retained beneath the leading edge of the anterior capsule 110. When viewed from above, such as in FIG. 2, the corners 130 define a generally triangular area or portion that is retained beneath the anterior capsule 110.

[0031] From the foregoing, it will be observed that numerous modifications and variations can be effected with departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that the present disclosure is to be considered an exemplification of the invention, and is not intended to limit the invention to the specific embodiments illustrated. The disclosure Is intended to cover by the appended claims all such modifications as fall with the scope of the claims.