Patent Description:
<NUM> This application is related to <CIT>, entitled "MODULAR INTROCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," now <CIT>, <CIT>, entitled "INTRAOCULAR LENS DESIGNS FOR IMPROVED STABILITY," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," now <CIT>, <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS AND METHODS," now <CIT>, <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS, TOOLS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS & METHODS," now <CIT>, <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS AND METHODS," now <CIT>, <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS AND METHODS," <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS & METHODS," now <CIT>, <CIT>, entitled "LASER ETCHING OF IN SITU INTRAOCULAR LENS AND SUCCESSIVE SECONDARY LENS IMPLANTATION," and <CIT>, entitled "MODULAR INTRAOCULAR LENS DESIGNS & METHODS. " <CIT> discloses an implantable capsule expander device for insertion within a lens capsule of an eye of a patient. <CIT> discloses an elastomeric optic that adapts in response to normal physiologic zonular tensioning forces.

<NUM> The present disclosure generally relates to intraocular lenses (IOLs). More specifically, the present disclosure relates to embodiments of IOL designs for improved stability in the capsular bag.

<NUM> The human eye 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.

<NUM> When age or disease causes the lens to become less transparent (e.g., cloudy), 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 from the capsular bag and placement of an artificial intraocular lens (IOL) in the capsular bag. In the United States, the majority of cataractous lenses are removed by a surgical technique called phacoemulsification. During this procedure, an opening (capsulorhexis) is made in the anterior side of the capsular bag and a thin phacoemulsification-cutting tip is inserted into the diseased lens and vibrated ultrasonically. The vibrating cutting tip liquefies or emulsifies the lens so that the lens may be aspirated out of the capsular bag. The diseased lens, once removed, is replaced by an IOL.

<NUM> After cataract surgery to implant an IOL, the optical result may be suboptimal. For example, shortly after the procedure, it may be determined that the refractive correction is erroneous leading to what is sometimes called "refractive surprise. " This can be caused, in part, by post-operative movement of the IOL in the capsular bag. Effective lens position (ELP), often measured using Scheimpflug photography (e.g., Pentacam, Oculus, Germany), is a measure of the anterior-posterior distance from the anterior surface of the cornea to the anterior surface of the lens (a. , anterior chamber depth or ACD). ELP can change significantly post-operatively, where a <NUM> shift in ELP corresponds to a <NUM> Diopter change in visual power. Thus, there is a need for an IOL that is more stable post-operatively to mitigate changes in ELP and reduce refractive surprise.

<CIT> discloses a modular intraocular lens system comprising a base and an intraocular lens. Said base comprises an anterior rim, a posterior rim, a recessed groove, and a pair of haptics.

<NUM> Embodiments of the present disclosure provide a base for an IOL and an IOL that improve ELP stability by, for example, increasing anterior-posterior stiffness of the IOL, increasing anterior-posterior dimensions of the IOL and/or increasing contact area with the equator of the bag to resist movement of the IOL as the bag collapses over time. These IOLs may be non-modular, unitary, or monolithic (i.e., single component) or modular (multiple component). In modular embodiments, the IOL system may include intraocular base and optic components, which, when combined, form a modular IOL.

<NUM> In one embodiment, a base for an IOL is provided according to claim <NUM>.

<NUM> In another embodiment, an IOL system is provided according to claim <NUM>.

<NUM> The embodiments of the present disclosure may be applied to a variety of IOL types, including fixed monofocal, multifocal, toric, accommodative, and combinations thereof. In addition, the embodiments of the present disclosure may be used to treat, for example: cataracts, large optical errors in myopic (near-sighted), hyperopic (far-sighted), and astigmatic eyes, ectopia lentis, aphakia, pseudophakia, and nuclear sclerosis.

<NUM> Various other aspects and advantages of embodiments of the present disclosure are described in the following detailed description and drawings.

<NUM> The drawings illustrate example embodiments of the present disclosure. The drawings are not necessarily to scale, may include similar elements that are numbered the same, and may include dimensions (in millimeters) and angles (in degrees) by way of example, not necessarily limitation. In the drawings:.

<NUM> Reference will now be made in detail to examples of the present disclosure, which are illustrated in the accompanying drawings. In the discussion that follows, relative terms such as "about," "substantially," "approximately," etc. are used to indicate a possible variation of ±<NUM>% in a stated value, numeric or otherwise, unless other variations are indicated.

<NUM> With reference to <FIG>, the human eye <NUM> is shown in cross section. The eye <NUM> has been described as an organ that reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina <NUM> allow conscious light perception and vision including color differentiation and the perception of depth. In addition, the human eye's non-image-forming photosensitive ganglion cells in the retina <NUM> receive light signals which affect adjustment of the size of the pupil, regulation and suppression of the hormone melatonin, and entrainment of the body clock.

<NUM> The eye <NUM> is not properly a sphere; rather it is a fused two-piece unit. The smaller frontal unit, more curved, called the cornea <NUM> is linked to the larger unit called the sclera <NUM>. The corneal segment <NUM> is typically about <NUM> (<NUM> in) in radius. The sclera <NUM> constitutes the remaining five-sixths; its radius is typically about <NUM>. The cornea <NUM> and sclera <NUM> are connected by a ring called the limbus. The iris <NUM>, the color of the eye, and its black center, the pupil, are seen instead of the cornea <NUM> due to the cornea's <NUM> transparency. To see inside the eye <NUM>, an ophthalmoscope is needed, since light is not reflected out. The fundus (area opposite the pupil), which includes the macula <NUM>, shows the characteristic pale optic disk (papilla), where vessels entering the eye pass across and optic nerve fibers <NUM> depart the globe.

<NUM> Thus, the eye <NUM> is made up of three coats, enclosing three transparent structures. The outermost layer is composed of the cornea <NUM> and sclera <NUM>. The middle layer consists of the choroid <NUM>, ciliary body <NUM>, and iris <NUM>. The innermost layer is the retina <NUM>, which gets its circulation from the vessels of the choroid <NUM> as well as the retinal vessels, which can be seen within an ophthalmoscope. Within these coats are the aqueous humor, the vitreous body <NUM>, and the flexible lens <NUM>. The aqueous humor is a clear fluid that is contained in two areas: the anterior chamber between the cornea <NUM> and the iris <NUM> and the exposed area of the lens <NUM>; and the posterior chamber, between the iris <NUM> and the lens <NUM>. The lens <NUM> is suspended to the ciliary body <NUM> by the suspensory ciliary ligament <NUM> (Zonule of Zinn), made up of fine transparent fibers. The vitreous body <NUM> is a clear jelly that is much larger than the aqueous humor.

<NUM> The crystalline lens <NUM> is a transparent, biconvex structure in the eye that, along with the cornea <NUM>, helps to refract light to be focused on the retina <NUM>. The lens <NUM>, by changing its shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina <NUM>. This adjustment of the lens <NUM> is known as accommodation, and is similar to the focusing of a photographic camera via movement of its lenses.

<NUM> The lens has three main parts: the lens capsule, the lens epithelium, and the lens fibers. The lens capsule forms the outermost layer of the lens and the lens fibers form the bulk of the interior of the lens. The cells of the lens epithelium, located between the lens capsule and the outermost layer of lens fibers, are found predominantly on the anterior side of the lens but extend posteriorly just beyond the equator.

<NUM> The lens capsule is a smooth, transparent basement membrane that completely surrounds the lens. The capsule is elastic and is composed of collagen. It is synthesized by the lens epithelium and its main components are Type IV collagen and sulfated glycosaminoglycans (GAGs). The capsule is very elastic and so causes the lens to assume a more globular shape when not under the tension of the zonular fibers, which connect the lens capsule to the ciliary body <NUM>. The capsule varies between approximately <NUM>-<NUM> micrometers in thickness, being thickest near the equator and thinnest near the posterior pole. The lens capsule may be involved with the higher anterior curvature than posterior of the lens.

<NUM> Various diseases and disorders of the lens <NUM> may be treated with an IOL. By way of example, not necessarily limitation, an IOL according to embodiments of the present disclosure may be used to treat cataracts, large optical errors in myopic (near-sighted), hyperopic (far-sighted), and astigmatic eyes, ectopia lentis, aphakia, pseudophakia, and nuclear sclerosis. However, for purposes of description, the IOL embodiments of the present disclosure are described with reference to cataracts, which often occurs in the elderly population.

<NUM> As seen in <FIG>, the shape of the lens <NUM> is generally symmetric about the visual axis <NUM>. However, the lens <NUM> is not symmetric about the sagittal plane <NUM>. Rather, the anterior side <NUM> of the lens <NUM> has a radius of curvature (RA) that is greater than the radius of curvature (RP) of the posterior side <NUM>. The equatorial diameter (D) resides more anteriorly, with the posterior lens thickness (TP) being greater than the anterior lens thickness (TA).

<NUM> Rosen et al. (<NUM>) published data suggesting the equatorial diameter D, the posterior lens thickness TP, the anterior lens thickness TA, and the anterior radius of curvature RA change with age, whereas the posterior radius of curvature RP and the ratio TA/TP remain constant. Using best-fit linear equations, Rosen et al. described the following age-dependent equations for these parameters (all in mm):
<NUM> <MAT>
<NUM> <MAT>
<NUM> <MAT>
<NUM> <MAT>
<NUM> <MAT> and
<NUM> <MAT>.

<NUM> These data or other empirically measured data may be used to describe the shape and size of the lens for a particular age group, such as cataracts in elderly patients at a mean age of <NUM>, by way of example, not limitation. Such data may be useful to determine the space available for an intraocular implant to be placed in the capsular bag. For example, assume an ocular implant (such as an IOL) is to be centered in the equatorial plane, with an anterior-posterior height "H" at radial distance "X" from its center point. Also assume it is desired to have the anterior and posterior sides of the implant at radial distance X come into contact with the walls of the capsular bag to mitigate migration of the implant. Mathematical modeling may be used to determine the height (H) of the lens capsule at any given radial distance (X) from the visual axis <NUM> along the equatorial plane.

<NUM> The total height H is equal to the sum of the anterior height (HA) and the posterior height (HP). The anterior height (HA) may be given by the equation HA = Y - (RA - TA). While RA and TA are empirically known, the distance (Y) from the equatorial plane may be given by the equation Y = (RA<NUM>-X<NUM>)^<NUM>. Combining these equations, the anterior height may be given by HA = (RA<NUM>-X<NUM>)^<NUM> - (RA - TA), and solved using empirical data. The posterior height (HP) may be similarly calculated using the posterior radius (RP) and posterior thickness (TP) solved using empirical data. Adding the posterior height (HP) to the anterior height (HA) provides the total height (H) at a distance (X) from the visual axis. Thus, the desired height (H) of the intraocular implant at radial distance X may be estimated such that the implant is in contact with the anterior and posterior walls of the capsular bag. Alternative mathematical models as described in the literature may be used as well.

<NUM> The following detailed description describes various embodiments of modular and non-modular IOL systems. Features described with reference to any one embodiment may be applied to and incorporated into other embodiments.

<NUM> With reference to <FIG>, a base <NUM> and a lens <NUM> form an embodiment of a modular IOL <NUM> when assembled. A general description of the modular IOL <NUM> follows, with further detailed provided in <CIT>, which is hereby fully incorporated by reference.

<NUM> With reference to <FIG>, the base <NUM> is shown in more detail. <FIG> is a perspective view, <FIG> is a top view, <FIG> is sectional view taken along line A-A in <FIG>, and <FIG> is a detailed sectional view of circle C in <FIG>. Dimensions (mm) are given by way of example, not necessarily limitation.

<NUM> The base <NUM> includes an annular ring <NUM> defining a center hole <NUM>. A pair of haptics <NUM> extend radially outward from the annular ring <NUM>. The annular ring <NUM> includes a lower rim <NUM>, an upper rim <NUM> and an inward-facing recess <NUM>, into which the lens <NUM> may be inserted to form modular IOL <NUM>.

<NUM> The upper rim <NUM> of annular ring <NUM> may include one or more notches <NUM> to provide access for a probe (e.g., Sinskey hook) intra-operatively, which allows the base <NUM> to be more easily manipulated. The haptics <NUM> may include holes <NUM> adjacent the annular ring <NUM> for the same purpose as notches <NUM>. A pair of square edges <NUM> may extend around the posterior periphery of the annular ring <NUM> to help reduce cellular proliferation (posterior capsular opacification or PCO) onto the lens <NUM>.

<NUM> With specific reference to <FIG>, the deep portion of the recess <NUM> may have a squared profile defined by horizontal posterior surface <NUM>, a horizontal anterior surface <NUM> and a vertical lateral or outer surface <NUM>. The recess may also include a flared anterior surface <NUM> extending radially inward and anteriorly outward from the horizontal anterior surface <NUM>, and a flared posterior surface <NUM> extending radially inward and posteriorly outward from the horizontal posterior surface <NUM>. The inside diameter of the posterior rim <NUM> may be smaller than the inside diameter of the anterior rim <NUM>. With this arrangement, the lens <NUM> may be placed through the circular opening defined by the anterior rim <NUM> to land or rest upon the posterior rim, and the flared anterior wall <NUM> together with the flared posterior wall <NUM> may act as a funnel to guide the tabs <NUM> and <NUM> of the lens <NUM> into the deep portion of the recess <NUM>. When fully seated in the recess <NUM>, the horizontal posterior wall <NUM>, the horizontal anterior wall <NUM> and the vertical lateral wall <NUM> form a keyed geometry with the corresponding horizontal and vertical sides of the tabs <NUM> and <NUM> to limit movement of the lens <NUM> relative to the base <NUM> in anterior, posterior and radial directions.

<NUM> As best seen in <FIG>, the base <NUM> may have an anterior-posterior height of H = HA + HP, where H is approximately <NUM>, HA is approximately <NUM> at a radial distance of approximately <NUM> from the center point CP, and HP is approximately <NUM> at a radial distance of <NUM> from the center point CP. However, as described previously, the posterior thickness TP of the native lens <NUM> is greater than the anterior thickness TA of the native lens <NUM>. Therefore, these relative dimensions may be adjusted. For example, HP may be made greater than HA such that the sagittal mid-plane MP of the base <NUM> is aligned (+/- <NUM>) with the equatorial plane of the lens <NUM> when the modular IOL <NUM> is implanted in the capsular bag. The ratio HA/HP may be constant at approximately <NUM> (±<NUM>), for example. In addition, H may be selected such that the anterior-most portion of the anterior rim <NUM> is in close proximity (within <NUM>) to the anterior side <NUM> of the lens <NUM> and the posterior-most portion of the posterior rim <NUM> is in close proximity (within <NUM>) to the posterior side <NUM> of the lens <NUM> when implanted in the capsular bag. Thus, by way of example, not limitation, HA may be approximately <NUM> to <NUM> at a radial distance of approximately <NUM> to <NUM> from the center point CP, and HP may be approximately <NUM> to <NUM> at a radial distance of <NUM> to <NUM> from the center point CP, maintaining a constant ratio HA/HP of approximately <NUM> (±<NUM>), for example.

<NUM> With reference to <FIG>, the lens <NUM> is shown in more detail. <FIG> is a perspective view, <FIG> is a top view, <FIG> is sectional view taken along line A-A in <FIG>, <FIG> is a detailed sectional view of circle B in <FIG> is a detailed top view of circle C in <FIG>. Dimensions (mm) are given by way of example, not necessarily limitation.

<NUM> The lens <NUM> may include an optic portion <NUM> and one or more tabs <NUM> and <NUM>. As shown, tab <NUM> is fixed, whereas tab <NUM> may be actuated. Fixed tab <NUM> may include a thru hole <NUM> so that a probe (e.g., Sinskey hook) or similar device may be used to engage the hole <NUM> and manipulate the tab <NUM>. Actuatable tab <NUM> may be actuated between a compressed position for delivery into the hole <NUM> of the base <NUM>, and an uncompressed extended position (shown) for deployment into the recess <NUM> of the base <NUM>, thus forming an interlocking connection between the base <NUM> and the lens <NUM>. It also is contemplated that actuatable tab <NUM> may be inserted into recess <NUM>, and may be actuated between the compressed position to facilitate entry of fixed tab <NUM> into recess <NUM>, and the uncompressed extended position to insert fixed tab <NUM> further into recess <NUM> to form the interlocking connection between base <NUM> and lens <NUM>.

<NUM> Actuatable tab <NUM> may include two members <NUM> and <NUM>, each with one end connected to the edge of the optic <NUM>, and the other end free, thus forming two cantilever springs. A rim <NUM> may extend around the perimeter of the optic <NUM>, terminating shy of the springs <NUM> and <NUM>, thus allowing the springs <NUM> and <NUM> to fully compress against the edge of the optic <NUM>. The rim <NUM> of the lens <NUM> may have an outside diameter that is greater than the inside diameter of the posterior rim <NUM> of the base <NUM> such that the lens <NUM> doesn't fall through the opening <NUM> of the base <NUM> and such that the lens <NUM> is circumferentially supported around its perimeter by the posterior rim <NUM> of the base <NUM>. A gusset with a guide hole <NUM> may be disposed between the two members <NUM> and <NUM> to facilitate manipulation by a probe. Similarly, a guide hole <NUM> may be provided in the fixed tab <NUM> to provide access for a probe (e.g., Sinskey hook) or similar device to manipulate the fixed tab <NUM> into the recess <NUM> in the base <NUM>. A notch <NUM> may be provided in the fixed tab <NUM> to provide asymmetry as a visual indicator that the anterior side is up (rather than down) when the notch is counter-clockwise of the hole <NUM>.

<NUM> As seen in <FIG>, the anterior and posterior sides of the optic <NUM> may have convex radii corresponding to the desired power (Diopter) of the optic. The fixed tab <NUM> and the spring tabs <NUM> and <NUM> may have a flared cross-section as shown. More specifically, and as better seen in the detailed view shown in <FIG>, the fixed tab <NUM> extends radially outward from the optic <NUM> from a thinner inner portion 504B to a flared thicker outer portion 504A. Hole <NUM> may extend through thinner inner portion 504B. The outermost profile of the thicker portion 504A has a squared profile with an anterior horizontal side, a posterior horizontal side, and a lateral or outer vertical side that are keyed to the recess <NUM> as described previously to minimized anterior-posterior and radial/lateral movement of the lens <NUM> relative to the base <NUM>. The thicker portion 504A also provides for improved engagement with the plunger of an injector to mitigate jamming of the lens <NUM> in the injector. The thinner portion 504B also provides an anterior and a posterior offset from the surfaces defining the recess <NUM> of the base <NUM>, thereby mitigating adhesion between the lens <NUM> and the base <NUM>. The same flared configuration and associated advantages also applies to each of the spring tabs <NUM> and <NUM> as shown.

<NUM> Commercially available IOLs typically have an equatorial diameter (excluding haptics) of about <NUM>, an anterior-posterior thickness of about <NUM> at <NUM> diameter and <NUM> at the center, providing an overall volume of about <NUM> mm3. Lens <NUM> is similarly dimensioned, but the base <NUM> adds substantially more volume. The base <NUM> may have an equatorial diameter (excluding haptics) of about <NUM>, an anterior-posterior thickness of about <NUM>, providing an overall volume of about <NUM> cubic millimeters [<NUM><NUM> base, <NUM><NUM> optic] when the lens is disposed into the base. Thus, the size of the combined base <NUM> and lens <NUM> is volumetrically much larger than conventional IOLs available on the market. This relatively larger volume is intended to fill the capsular bag more like a natural lens, thus increasing the stability of the modular IOL <NUM> and reducing post-operative migration due to the bag collapsing around the base <NUM>. By way of comparison, a typical natural lens has an equatorial diameter of about <NUM>, an anterior-posterior dimension of about <NUM> for a corresponding volume of about <NUM> mm3. Due to anatomic variability, a natural lens may have a volume ranging from <NUM><NUM> to <NUM><NUM>. Thus, the modular IOL <NUM> (base <NUM> plus lens <NUM>) consumes greater than <NUM>% (about <NUM>% to <NUM>%) of the volume of the bag after the natural lens has been extricated, whereas a conventional IOL consumes less than or equal to <NUM>% (about <NUM>% to <NUM>%) of the volume of the bag. In other words, the modular IOL <NUM> consumes about twice the volume of the bag compared to a conventional IOL.

<NUM> Also by comparison to conventional IOLs, modular IOL <NUM>, by virtue of the annular ring <NUM> of the base <NUM>, provides a relatively large diameter and rigid platform that resists deflection (i.e., increased stiffness in the sagittal plane, thereby improving anterior-posterior stability). Coupled with the relatively long sweeping haptics <NUM> which offer a significant relative increase in surface contact with the capsular bag, the modular IOL <NUM> provides superior centering and stability within the capsular bag.

<NUM> The ability to resist deflection was demonstrated in a bench test comparing the performance of modular IOL <NUM> to a commercially available IOL (Alcon model SA60), the results of which are shown in <FIG>. In the test set-up, the test IOL was placed in a <NUM> inside diameter simulated capsular bag and the assembly was submerged in a warm bath. Various loads were applied to the middle of test IOL while in a horizontal orientation, and the resulting downward displacement was measured. As can be seen from the results shown in <FIG>, the commercially available IOL was displaced roughly <NUM> times the amount that the modular IOL <NUM> was displaced, and the commercially available IOL failed to support a load of <NUM> grams as the haptics were displaced out of the simulated capsular bag. This demonstrates the significant relative increase in stiffness of modular IOL <NUM> compared to a common commercially available IOL.

<NUM> This test set-up may be compared to a mechanical model of a center load on beam with two simple supports described by F=keqΔx, where F = applied force, keq = equivalent stiffness and Δx = displacement. Equivalent stiffness takes into account the cross-sectional moment of inertia of the beam as well as the material properties of the beam (Young's elastic modulus). However, since IOLs are made of plastic (rather than an elastic material such as metal), the equivalent stiffness will vary over a range of applied forces. In the described bench test, the modular IOL <NUM> had an equivalent stiffness of approximately <NUM> to <NUM>/mm over a range of applied loads of <NUM> to <NUM>, whereas the commercially available IOL had an equivalent stiffness of approximately <NUM> to <NUM>/mm over a range of applied loads of <NUM> to <NUM>.

<NUM> In general, when the base <NUM> and lens <NUM> are assembled to form modular IOL <NUM>, the features may be configured such that the mid-plane of the optic <NUM> is parallel with the mid-plane of the base <NUM>, and the central (anterior-posterior) axis of the optic <NUM> is coincident and collinear with the central (anterior-posterior) axis of the base <NUM>. Assuming anatomic symmetry of the native lens capsule and centration of the base <NUM> in lens capsule, this configuration essentially aligns the central axis of the optic <NUM> with the central (anterior-posterior) axis of the capsular bag, thus providing centration of the optic <NUM>. However, there may be instances where the visual (foveal) axis is not aligned with the anatomic (pupillary axis), wherein the difference is called angle of kappa. In such instances, it may be desirable to offset the central axis of the optic <NUM> relative to the base <NUM>, thus providing de-centration. This may be accomplished, for example, by configuring the tabs <NUM> and <NUM>, the recess <NUM> and/or the haptics <NUM> such that the central (anterior-posterior) axis of the optic <NUM> is laterally (nasally or temporally) offset relative to the central (anterior-posterior) axis of the base <NUM>.

<NUM> By way of example, not limitation, the lateral walls defining the recess <NUM> in the base <NUM> may be offset relative to the haptics <NUM> so that the central axis of the optic <NUM> is offset. Different offsets could be provided, for example, <NUM> through <NUM> at. <NUM> increments. Angular orientation marks on the base <NUM> and lens <NUM> may be provided to indicate the direction of the offset (nasally or temporally). Similarly, the mid-plane of the assembled base <NUM> and optic <NUM> may be tilted relative to the equatorial plane of the native capsular bag. To compensate for this tilt, for example, the tabs <NUM> and <NUM>, the recess <NUM> and/or the haptics <NUM> may be configured such that the mid-plane of the optic <NUM> is counter-tilted.

<NUM> The base <NUM> and lens <NUM>, including the alternative embodiments described herein, may be formed by cryogenically machining and polishing hydrophobic acrylic material. Optionally, the base <NUM> may be manufactured by forming two (anterior and posterior) components and adhesively connecting them together. For example, the two components may be cryogenically machined hydrophilic acrylic connected together by a U. curable adhesive. Alternatively, the two components may be formed of different materials adhesively connected together. For example, the anterior component may be formed of hydrophilic acrylic which does not adhere to ocular tissue, and the posterior component may be formed of hydrophobic acrylic which does adhere to ocular tissue.

<NUM> As a further alternative, the base <NUM> may be manufactured by cryogenic machining the first component and over-molding the second component. The first component may include geometric features that become interlocked when over-molded, thus mitigating the need for adhesive to connect the components. For example, the base <NUM> may be manufactured by cryogenic machining of hydrophilic acrylic to form the posterior component, and over-molding the anterior component of a moldable material such as silicone.

<NUM> While hydrophobic acrylic renders the base <NUM> and lens <NUM> visible using optical coherence tomography (OCT), it may be desirable to incorporate a material that enhances OCT visualization. Example "OCT-friendly" materials include but are not limited to polyvinyl chloride, glycol modified poly (ethylene terephthalate) (PET-G), poly (methyl methacrylate) (PMMA), and a polyphenylsulfone, such as that sold under the brand name RADEL™, as described in <CIT> Such OCT-friendly materials may be applied to or incorporated into a portion of the base <NUM> or lens <NUM>.

<NUM> By way of example, a concentric ring of OCT-friendly material may be applied to each of the lower and upper rims <NUM>/<NUM>. The rings may have different diameters to aid in detecting tilt of the base. Also by way of example, OCT-friendly material may be applied to the tabs <NUM>/<NUM> of the lens <NUM>. This may aid in determining if the base <NUM> and lens <NUM> are correctly assembled in the eye. Points of OCT-friendly material may be applied to portions of the base <NUM> that line up to corresponding OCT-friendly points on the optic <NUM> to indicate proper assembly in the eye.

<NUM> As an alternative to solid material, the base <NUM> and lens <NUM> may be made of hollow material that can be subsequently inflated in the eye. In this arrangement, the base <NUM> and lens <NUM> may be made from molded silicone, for example, and inflated with a liquid such as saline, silicone gel or the like using a syringe and needle. The needle may pierce the wall of the base <NUM> and lens <NUM> after implantation in the eye to inflate the components. The material may self-seal after removal of the needle. As an alternative to a hollow material, the base <NUM> and lens <NUM> may be formed of a sponge-like material such as silicone hydrogel that swells upon hydration. Both approaches allow the size of the corneal incision to be smaller, as the base <NUM> and lens <NUM> are delivered in an uninflated or unswelled state and subsequently inflated or swelled once inside the eye.

<NUM> In general, the modular IOL <NUM>, comprising the assembled base <NUM> and lens <NUM>, including the alternative embodiments described herein, allows for the lens <NUM> to be adjusted or exchanged while leaving the base <NUM> in place, either intra-operatively or post-operatively. Examples of instances where this may be desirable include, without limitation: exchanging the lens <NUM> to correct a suboptimal refractive result detected intra-operatively; exchanging the lens <NUM> to correct a suboptimal refractive result detected post-operatively (residual refractive error); rotationally adjusting the lens <NUM> relative to the base <NUM> to fine tune toric correction; laterally adjusting the lens <NUM> relative to the base <NUM> for alignment of the optic with the true optical axis (which may not be the center of the capsular bag); and exchanging the lens <NUM> to address the changing optical needs or desires of the patient over longer periods of time. Examples of the latter instance include, but are not limited to: an adult or pediatric IOL patient whose original optical correction needs to be changed as s/he matures; a patient who wants to upgrade from a monofocal IOL to a premium IOL (toric, multifocal, accommodating or other future lens technology); a patient who is not satisfied with their premium IOL and wants to downgrade to monofocal IOL; and a patient who develops a medical condition where an IOL or a particular type of IOL is contra-indicated.

<NUM> With reference to <FIG>, an alternative modular IOL <NUM> is shown in perspective and cross-sectional views, respectively. Alternative modular IOL <NUM> may include an alternative base <NUM> and the lens <NUM> as described above. As will be appreciated by the following description, alternative base <NUM> may be similar to base <NUM> except for anterior rim <NUM> and posterior rim <NUM>, the description of the similar aspects and advantages being incorporated herein by reference. Alternative base <NUM> includes an annular ring defining a center hole. A pair of haptics <NUM> extend radially outward from the annular ring. The annular ring includes a lower rim <NUM>, an upper rim <NUM> and an inward-facing recess <NUM>, into which the lens <NUM> may be inserted to form modular IOL <NUM>.

<NUM> With specific reference to <FIG>, the lower rim <NUM> and upper rim <NUM> may have a relatively exaggerated height and may be angled radially inward to form a funnel leading to the recess <NUM>. With this arrangement, the actuatable tabs <NUM> of the lens may be compressed and the lens <NUM> may be placed through the circular opening defined by the anterior rim <NUM>, with the funnel shape of the anterior rim <NUM> guiding the tabs <NUM> and <NUM> into the recess <NUM> of the base <NUM> to form a keyed geometry to limit movement of the lens <NUM> relative to the base <NUM> in anterior, posterior and radial directions. The funneled shape of the posterior rim <NUM> prevents the lens <NUM> from falling posteriorly during insertion of the lens <NUM> into the base <NUM>.

<NUM> The base <NUM> may have the dimensions as shown by way of example, not necessary limitation. As best seen in <FIG>, the rims <NUM> and <NUM> of the base <NUM> may have a combined anterior-posterior height that is <NUM> to <NUM> (or more) times the maximum thickness of the optic portion <NUM> of the lens <NUM>. For example, the combined height of the rims <NUM> and <NUM> may be approximately <NUM> at a radial distance of approximately <NUM> from the center point. As described previously, the height of posterior rim <NUM> may be made greater than the height of anterior rim <NUM> such that the sagittal mid-plane of the base <NUM> is aligned (+/- <NUM>) with the equatorial plane of the lens <NUM> when the modular IOL <NUM> is implanted in the capsular bag. The height ratio of the anterior rim <NUM> to the posterior rim <NUM> may be constant at a value less than <NUM> such as approximately <NUM> (±<NUM>), for example. As shown, the combined height of the anterior rim <NUM> and the posterior rim <NUM> are selected such that the anterior-most portion of the anterior rim <NUM> is in close proximity (within <NUM>) to or pushing against the anterior side <NUM> of the lens <NUM> and the posterior-most portion of the posterior rim <NUM> is in close proximity (within <NUM>) to or pushing against the posterior side <NUM> of the lens <NUM> when implanted in the capsular bag.

<NUM> With reference to <FIG>, an alternative base <NUM> for use with a conventional IOL <NUM> is shown in perspective views, where <FIG> shows the base <NUM> standing alone and <FIG> shows the combined base <NUM> and conventional IOL <NUM> assembled to form modular IOL <NUM>. Alternative base <NUM> is similar to base <NUM> described previously, with the exception of inverted T-slots <NUM>, the description of the similar aspects and advantages being incorporated herein by reference.

<NUM> The base <NUM> includes an annular ring <NUM> defining a center hole <NUM>. A pair of haptics <NUM> extend radially outward from the annular ring <NUM>. The annular ring <NUM> includes a lower rim <NUM>, an upper rim <NUM> and an inward-facing recess <NUM>, into which the conventional IOL <NUM> may be inserted to form modular IOL <NUM>. The upper rim <NUM> of annular ring <NUM> may include one or more notches <NUM> to provide access for a probe (e.g., Sinskey hook) intra-operatively, which allows the base <NUM> to be more easily manipulated. The haptics <NUM> may include holes <NUM> adjacent the annular ring <NUM> for the same purpose as notches <NUM>.

<NUM> The annular ring <NUM> may include a pair of inverted-T-shaped slots <NUM> to accommodate the diametrically opposed haptics <NUM> of the conventional IOL <NUM>. When the haptics <NUM> of the conventional IOL <NUM> are placed in the slots <NUM>, the posterior side of the optic portion <NUM> of the conventional IOL <NUM> may rest upon the anterior surface of the posterior rim <NUM>. The posterior portion of the slots <NUM> may have a greater width than the anterior portion thereof to accommodate the angle of the haptics <NUM> and to lock the IOL <NUM> to the base <NUM> when rotated relative thereto. The addition of the base <NUM> adds to the anterior-posterior rigidity and height of a conventional IOL <NUM>, thereby improving its stability.

<NUM> With reference to <FIG>, perspective, cross-sectional and top views, respectively, of a non-modular IOL <NUM> is shown schematically. Non-modular IOL <NUM> incorporates several of the stability advantages described previously, but in a non-modular configuration. IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. IOL <NUM> also includes two or more haptics <NUM> extending radially outward from the periphery of the optic portion <NUM>. Each haptic includes a posterior flange <NUM> and an anterior flange <NUM> extending radially inward and flared in an outward posterior and an outward anterior direction, respectfully, from an outer rim <NUM>. Each haptic <NUM> includes a connecting arm <NUM> that connects the outer rim <NUM> to the periphery of the optic <NUM>. Each connecting arm <NUM> may include a window <NUM> for added flexibility. The posterior flange <NUM> and the anterior flange <NUM> are configured to compress relative to each other in an anterior-posterior direction, acting like cantilever leaf springs about outer rim <NUM>.

<NUM> With specific reference to <FIG>, which is a cross-sectional view taken along line B-B in <FIG>, it can be appreciated that the posterior flange <NUM> is sized and configured differently than anterior flange <NUM> in order to conform to the shape of the capsular bag. As described previously, the posterior thickness of the native lens is greater than the anterior thickness of the native lens. In order for the anterior flange <NUM> to conform to the anterior side <NUM> of the lens capsule and the posterior flange <NUM> to conform to the posterior side <NUM> of the lens capsule, the anterior flange <NUM> may have an anterior height HA and arc length that is less than the posterior height HP and arc length of the posterior flange <NUM>. For example, HP may be made greater than HA such that the sagittal mid-plane MP of the base <NUM> is aligned (+/- <NUM>) with the equatorial plane of the lens capsule when the IOL <NUM> is implanted in the capsular bag. The ratio HA/HP may be constant at approximately <NUM> (±<NUM>), for example.

<NUM> With specific reference to <FIG>, the radial length (in the sagittal plane) of the posterior flange <NUM> and anterior flange <NUM> may be selected such that the inner-most edge does not interfere with the field of vision through the optic <NUM>. In other words, the posterior flange <NUM> and the anterior flange <NUM> may extend radially inward from the outer rim <NUM> up to the outer diameter of the optic portion <NUM>, where the inner edge of the posterior flange <NUM> and the anterior flange <NUM> forms an arc conforming to the outside diameter of the optic <NUM>. The outer rim <NUM> may also form an arc, wherein the haptics <NUM> conform the circular shape of the equator of the natural lens capsule. By way of example, not necessarily limitation, the arc shape of the haptics <NUM> may extend <NUM>°-<NUM>°, <NUM>°-<NUM>°, or <NUM>°-<NUM>° around the circumference of the optic <NUM>. The larger the arc length of the haptics, the greater the contact area with the equator of the natural lens capsule, the greater the stability of the IOL <NUM> in the capsular bag, but this must be balanced against the deliverability of the IOL <NUM> through a small incision using an injector.

<NUM> With reference to <FIG>, alternative non-modular IOLs <NUM> and <NUM>, respectively, are shown in perspective view. IOLs <NUM> and <NUM> are similar to IOL <NUM> described above in that the haptics include flared flanges for improved stability; the description of the similar aspects and advantages being incorporated herein by reference.

<NUM> With specific reference to <FIG>, IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. IOL <NUM> also includes two or more haptics <NUM> extending radially outward from the periphery of the optic portion <NUM>. Each haptic <NUM> includes a posterior flange <NUM> and an anterior flange <NUM> extending radially inward and flared in an outward posterior and an outward anterior direction, respectfully, from an outer rim <NUM>. Each haptic <NUM> includes a pair of connecting arms <NUM> that connect the outer rim <NUM> to the periphery of the optic <NUM>. Each pair of connecting arms <NUM> may include a window <NUM> for added flexibility. The posterior flange <NUM> and the anterior flange <NUM> are configured to compress relative to each other in an anterior-posterior direction, acting like cantilever leaf springs about outer rim <NUM>. Compared to IOL <NUM>, the flanges <NUM> and <NUM> of IOL <NUM> have a smaller radial length (in the sagittal plane) extending from the outer rim <NUM> toward the optic <NUM>. In addition, a gap <NUM> is provided between the connecting arms <NUM> and the flanges <NUM> and <NUM> along the inside connection to the outer rim <NUM> to provide space for the flanges <NUM> and <NUM> to compress and fold down toward the optic <NUM>. The gap <NUM> allows the connection between the outer rim <NUM> and the flanges <NUM> and <NUM> to function as a resilient hinge and allows the flanges <NUM> and <NUM> to better conform to the inside of the capsular walls that may vary in size and dimension.

<NUM> With reference to <FIG>, IOL <NUM> is similar to IOL <NUM>, the description of similar aspects and advantages being incorporated herein by reference. IOL <NUM> includes one or more haptics <NUM> including curvilinear arms <NUM> (rather than connecting arms <NUM>) extending from the periphery of optic <NUM> to form the outer rim <NUM> from which the flanges <NUM> and <NUM> extend. As in the prior embodiment, a gap <NUM> is provided to enhance the flexibility of the flanges <NUM> and <NUM> relative to the curvilinear arms <NUM> along outer rim <NUM> such that the connection therebetween functions as a resilient hinge.

<NUM> With reference to <FIG>, an alternative non-modular IOL <NUM> is shown schematically. <FIG> is a top view of the IOL <NUM> and <FIG> is a cross-sectional view taken along line B-B in <FIG>. IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. IOL <NUM> also includes a pair of haptics <NUM> extending outwardly from the optic portion <NUM>. A pair of gusset plates <NUM> connects the haptics <NUM> to the optic portion <NUM>. Whereas a conventional IOL provides haptics extending from the optic portion, IOL <NUM> utilizes the gusset plates <NUM> to push the attachment location of the haptics <NUM> radially outward, thereby relatively increasing the anterior-posterior stiffness of the IOL in the sagittal plane. IOL <NUM> also includes a posteriorly extending ridge <NUM> around the periphery of the optic <NUM> and the periphery of the gusset plates <NUM>, excluding the haptics <NUM> and the junction of the haptics <NUM> to the gusset plates <NUM>. The ridge <NUM> increases the cross-sectional moment of inertia of the IOL <NUM> in the sagittal plane, thereby increasing its stiffness and stability, without affecting the flexibility of the haptics <NUM>. As seen in cross-section, the ridge <NUM> may have an inside fillet and an outside square edge as shown, to inhibit cellular proliferation onto the optic portion <NUM>. By way of example, not necessarily limitation, the haptics may have an outside extent of <NUM> (haptic tip to haptic tip), the optic may have a diameter of <NUM> to <NUM>, and the gusset plates <NUM> may have a mean sagittal width of <NUM> to <NUM>. Thus, with a <NUM> diameter optic <NUM>, the haptics <NUM> may be attached to the gusset plates <NUM> at a diameter of <NUM> to <NUM>.

<NUM> With reference to <FIG>, another alternative non-modular IOL <NUM> is shown schematically. <FIG> is a top view of the IOL <NUM> and <FIG> is a cross-sectional perspective view taken along line B-B in <FIG>. As will be appreciated by the following description, IOL <NUM> may be similar to IOL <NUM> except with regard to ridge <NUM>, the description of the similar aspects and advantages being incorporated herein by reference. IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. IOL <NUM> also includes a pair of haptics <NUM> extending outwardly from the optic portion <NUM>. A pair of gusset plates <NUM> connects the haptics <NUM> to the optic portion <NUM>. Whereas a conventional IOL provides haptics extending from the optic portion, IOL <NUM> utilizes the gusset plates <NUM> to push the attachment location of the haptics <NUM> radially outward, thereby relatively increasing the anterior-posterior stiffness of the IOL in the sagittal plane. IOL <NUM> also includes a ridge <NUM> that extends around the periphery of the optic <NUM> and extends in both an anterior and a posterior direction. The ridge <NUM> increases the cross-sectional moment of inertia of the IOL <NUM> in the sagittal plane, thereby increasing its stiffness and stability, without affecting the flexibility of the gusset plates <NUM> or the haptics <NUM>. As seen in cross-section, the ridge <NUM> may be rounded in an oval shape.

<NUM> With reference to <FIG>, yet another alternative non-modular IOL <NUM> is shown schematically. <FIG> is a top view of the IOL <NUM> and <FIG> is a cross-sectional view taken along line B-B in <FIG>. As will be appreciated by the following description, IOL <NUM> may be similar to IOL <NUM> except with regard to a gusset or support portion <NUM> and one or more ridges <NUM>, the description of the similar aspects and advantages being incorporated herein by reference.

<NUM> IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. IOL <NUM> also includes a pair of haptics <NUM> extending outwardly from the optic portion <NUM>. The or support portion <NUM> extends around the periphery of the optic portion <NUM> and connects the haptics <NUM> to the optic portion <NUM>. Whereas a conventional IOL provides haptics extending from the optic portion, IOL <NUM> utilizes the support portion <NUM> to push the attachment location of the haptics <NUM> radially outward, thereby relatively increasing the anterior-posterior stiffness of the IOL <NUM> in the sagittal plane.

<NUM> The support portion <NUM> may surround the optic <NUM>. For example, the support portion <NUM> may extend concentrically, a full <NUM>°, around a radially-outer periphery of the optic <NUM>. In one example, the support portion <NUM> may include an annular plate that forms a band around the optic <NUM>. The plate may have a substantially constant width between its inner and outer circumferences.

<NUM> The support portion <NUM> may include an anterior-facing surface 1204a and a posterior-facing surface 1204b. At least one of the anterior-facing and posterior-facing surfaces 1204a and 1204b of the support portion <NUM> may extend substantially perpendicular to an optical axis 1202a of the optic <NUM>. Optic <NUM> may have a curved anterior-facing surface 1202b and/or a curved posterior-facing surface 1202c. An annular concave region <NUM> may be formed on the anterior and/or posterior sides of IOL <NUM>, where the support portion <NUM> meets optic <NUM>, due to the angle formed between the anterior-facing surfaces 1204a and 1202b of the support portion <NUM> and the optic <NUM>, respectively, and/or the angle formed between the posterior-facing surfaces 1204b and 1202c of the support portion <NUM> and the optic <NUM>, respectively.

<NUM> A thickness of the support portion <NUM>, measured between the anterior-facing and posterior-facing surfaces 1204a and 1204b of the support portion <NUM>, may be substantially equal to a thickness of the radially-outer periphery of the optic <NUM> (measured between the peripheries of the anterior-facing and posterior-facing surfaces 1202b and 1202c of the optic <NUM>). Additionally or alternatively, the thickness of the support portion <NUM> may be substantially equal to a thickness of the haptics <NUM> (measured between anterior-facing and posterior-facing surfaces 1206a and 1206b of the haptics <NUM>).

<NUM> IOL <NUM> also may include one or more ledges or ridges <NUM>. The one or more ridges <NUM> may extend around, along, and/or about one or more portions of the radially-outer peripheries of the support portion <NUM> and haptics <NUM>. In one example, the one or more ridges <NUM> may include one or more ridges that extend in an anterior direction from the anterior-facing surface 1204a of the support portion <NUM>. For example, the one or more anteriorly extending ridges my include a ridge 1208a and/or a ridge 1208b. Additionally or alternatively, the one or more ridges <NUM> may include one or more ridges that extend in a posterior direction from the posterior-facing surface 1204b of the support portion <NUM>. For example, the one or more posteriorly extending ridges may include a ridge 1208c and/or a ridge 1208d. The one or more ridges <NUM> may increase the cross-sectional moment of inertia of the entire IOL <NUM> in the sagittal plane, including the optic <NUM>, support portion <NUM> and haptics <NUM>, thereby increasing its stiffness and stability. While <FIG> show a pair of anteriorly extending ridges 1208a and 1208b and a pair of posteriorly extending ridges 1208c and 1208d, it is contemplated that fewer ridges may be employed. For example, IOL <NUM> may include only the anteriorly extending ridges 1208a and 1208b, or only the posteriorly extending ridges 1208c and 1208d.

<NUM> As seen in cross-section in <FIG>, the one or more ridges <NUM> may have a squared profile to mitigate cellular proliferation onto the optic <NUM>. For example, one or more of ridges 1208a, 1208b, 1208c, and 1208d may include opposing surfaces 1208e and 1208f that extend substantially perpendicular to the anterior-facing and/or posterior-facing surfaces 1204a and 1204b of the support portion <NUM>. Additionally or alternatively, opposing surfaces 1208e and 1208f may extend substantially parallel to one another. Additionally or alternatively, one or more of ridges 1208a, 1208b, 1208c, and 1208d may include an end surface <NUM> that extends substantially parallel to the anterior-facing and/or posterior facing surfaces 1204a and 1204b of the support portion <NUM>. The surfaces 1208f may be flush with radially-outer peripheral surfaces of the support portion <NUM> and/or the haptics <NUM>.

<NUM> The ridge 1208a may extend on, along, or around the outside curvature of one of haptics <NUM>, and may be tapered (e.g., may taper down in height) at the tip of that haptic <NUM> or proximate the tip of that haptic <NUM>. The tapered portion may define a first end of the ridge 1208a. The ridge 1208a may have a second end opposite its first end. The second end may be tapered (e.g., may taper down in height). The tapering at the second end of the ridge 1208a may have a greater slope than the tapering at the first end. Ridges 1208b, 1208c, and 1208d may be similarly shaped.

<NUM> In between their tapered ends, ridges 1208a, 1208b, 1208c, and 1208d may have heights (measured in the anterior-posterior direction relative to surfaces of the support portion <NUM>) such that the anterior-facing surface 1202b of the optic <NUM> may extend anterior to ridge 1208a and/or ridge 1208b, and/or the posterior-facing surface 1202c of the optic <NUM> may extend posterior to ridge 1208c and/or ridge 1208d. It also is contemplated that one or more of ridges 1208a, 1208b, 1208c, 1208d may have a constant height in between its tapered ends.

<NUM> As best seen in <FIG>, the ridges 1208a and 1208b may be discrete ridges, separated by a gap. Additionally or alternatively, the ridges 1208c and 1208d may be discrete ridges, separated by a gap. For example, an inside curvature of the haptics <NUM> may exclude ridges to allow for radial compression of the haptics <NUM> toward the optic portion <NUM>.

<NUM> Ridge 1208a may include a first curved portion <NUM> and a second curved portion 1208i. First and second curved portions <NUM> and 1208i may be substantially concave, viewed from the perspective of optic <NUM>. Where first and second curved portions <NUM> and 1208i meet they may form a convex portion 1208j of ridge 1208a. Ridges 1208b, 1208c, and/or 1208d may be similarly shaped.

<NUM> The one or more ridges <NUM> may be arranged in pairs. For example, ridges 1208a, 1208b may form a first, anterior pair or ridges, and/or ridges 1208c, 1208d may form a second, posterior pair of ridges. With respect to the pair of ridges 1208a and 1208b, an end portion of one of the ridges may extend past the opposing end portions of the other ridge and toward an intermediate portion of the other ridge. A similar arrangement may exist for pair of ridges 1208c and 1208d.

<NUM> With reference to <FIG>, a variety of alternative non-modular IOLs 1300A, 1300B and 1300C are shown in perspective view. Each IOL <NUM> includes an optic portion <NUM> that may be monofocal (fixed focal length), accommodating (variable focal length), toric, multifocal, or extended depth-of-focus pattern, for example. Each IOL <NUM> also includes two or more haptics <NUM> connected to the optic portion <NUM> via connecting arms <NUM>. By comparison to a conventional IOL where the haptics are curvilinear to provide radial spring force in addition to contact with inside equator of the lens capsule, connecting arms <NUM> provide radial spring force independent of the haptics <NUM>, and haptics <NUM> may be circular to maintain the same amount of contact area with the inside equator of the lens capsule independent of radial compression of the connecting arms <NUM>. This configuration provides more consistent stability of the IOL <NUM> in the capsular bag, regardless of the size of the capsular bag. The haptics <NUM> may extend <NUM>° - <NUM>°, <NUM>° - <NUM>°, or <NUM>° - <NUM>° around the circumference of the optic <NUM>, and may have a constant radius of about <NUM> to <NUM>, for example. The connecting arms <NUM> may be in the form of a multi-bar cantilever (zig-zag) spring 1312A, a single bar cantilever (curvilinear) spring 1312B, or a multi-leaf spring 1312C, for example.

Claim 1:
A base (<NUM>) for a modular intraocular lens system (<NUM>) for implantation into a capsular bag, the base (<NUM>) being suitable for receiving a lens (<NUM>) to form an intraocular lens system (<NUM>), the base (<NUM>) comprising:
an annular body with a center hole extending therethrough, the annular body defining a recess (<NUM>) extending around an inside circumference thereof, the recess (<NUM>) being adapted for receiving the lens (<NUM>);
an anterior rim (<NUM>) extending around an anterior side of the annular body, the anterior rim including an anterior opening; and
a posterior rim (<NUM>) extending around a posterior side of the annular body, the posterior rim including a posterior opening;
wherein the anterior (<NUM>) and posterior rims (<NUM>) are angled radially inward to form a funnel leading to the recess (<NUM>); and
further wherein the annular body extends between the anterior rim (<NUM>) and the posterior rim (<NUM>), the recess (<NUM>) comprising an anterior ledge, a posterior ledge, and a sidewall extending in an anterior-posterior direction, perpendicular to a longitudinal axis of the base (<NUM>);
wherein the base (<NUM>) comprises a pair of haptics (<NUM>) protruding radially outwardly from the annular body.