US20060227286A1 - Optimal IOL shape factors for human eyes - Google Patents

Optimal IOL shape factors for human eyes Download PDF

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US20060227286A1
US20060227286A1 US11397305 US39730506A US2006227286A1 US 20060227286 A1 US20060227286 A1 US 20060227286A1 US 11397305 US11397305 US 11397305 US 39730506 A US39730506 A US 39730506A US 2006227286 A1 US2006227286 A1 US 2006227286A1
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range
optic
shape factor
mm
lens
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Abandoned
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US11397305
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Xin Hong
Stephen Van Noy
Jihong Xie
Dan Stanley
Mutlu Karakelle
Michael Simpson
Xiaoxiao Zhang
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Novartis AG
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Alcon Inc
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/14Eye parts, e.g. lenses, corneal implants; Implanting instruments specially adapted therefor; Artificial eyes
    • A61F2/16Intraocular lenses
    • A61F2/1613Intraocular lenses having special lens configurations, e.g. multipart lenses; having particular optical properties, e.g. pseudo-accommodative lenses, lenses having aberration corrections, diffractive lenses, lenses for variably absorbing electromagnetic radiation, lenses having variable focus
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/14Eye parts, e.g. lenses, corneal implants; Implanting instruments specially adapted therefor; Artificial eyes
    • A61F2/16Intraocular lenses
    • A61F2/1613Intraocular lenses having special lens configurations, e.g. multipart lenses; having particular optical properties, e.g. pseudo-accommodative lenses, lenses having aberration corrections, diffractive lenses, lenses for variably absorbing electromagnetic radiation, lenses having variable focus
    • A61F2/1637Correcting aberrations caused by inhomogeneities; correcting intrinsic aberrations, e.g. of the cornea, of the surface of the natural lens, aspheric, cylindrical, toric lenses
    • GPHYSICS
    • G02OPTICS
    • G02CSPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
    • G02C7/00Optical parts
    • G02C7/02Lenses; Lens systems ; Methods of designing lenses

Abstract

The present invention provides an ophthalmic lens (e.g., an intraocular lens) having an optic with an anterior surface and a posterior surface, which exhibits a shape factor (defined as a ratio of the sum of the anterior and posterior curvatures to the difference of such curvatures) in a range of about −0.5 to about 4. In a related aspect, the shape factor of the optic lies in a range of about 0 to about 2. The above shape factors give rise to a plurality of different lens shapes, such as concave-convex, plano-convex and plano-concave.

Description

    RELATED APPLICATION
  • The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/668,520 entitled “Intraocular Lens,” filed on Apr. 5, 2005, which is herein incorporated by reference.
  • A U.S. patent application entitled, “Intraocular Lens,” assigned to the assignee of the present application, and filed concurrently herewith, is herein also incorporated by reference.
  • BACKGROUND
  • The present invention relates generally to ophthalmic lenses, and more particularly, to intraocular lenses (IOLs) having optimal shape factors.
  • Intraocular lenses are routinely implanted in patients' eyes during cataract surgery to replace the clouded natural lens. The post-operative performance of such IOLs, however, can be degraded due to a variety of factors. For example, aberrations introduced as a result of misalignment of the implanted IOL relative to the cornea, and/or the inherent aberrations of the eye, can adversely affect the lens's optical performance.
  • Accordingly, there is a need for improved IOLs that can provide a more robust optical performance.
  • SUMMARY
  • In one aspect, the present invention provides an ophthalmic lens (e.g., an intraocular lens) having an optic with an anterior surface and a posterior surface. The optic exhibits a shape factor in a range of about −0.5 to about 4. In a related aspect, the shape factor of the optic lies in a range of about 0 to about 2. The above shape factors give rise to a plurality of different lens shapes, such as, bi-convex, plano-convex, plano-concave and convex-concave.
  • In another aspect, the optic is formed of a biocompatible polymeric material. By way of example, the optic can be formed of a soft acrylic polymeric material. Other examples of suitable materials include, without limitation, hydrogel and silicone materials.
  • In another aspect, at least one surface of the optic can be characterized by an aspheric base profile (i.e., a base profile that exhibits deviations from sphericity). By way of example, the base profile can be characterized by a conic constant in a range of about −73 to about −27.
  • In a related aspect, the aspheric profile of the lens surface can be defined in accordance with the following relation: z = cr 2 1 + 1 - ( 1 + k ) c 2 r 2
    wherein,
  • c denotes the curvature of the surface at its apex (at its intersection with the optical axis),
  • r denotes the radial distance from the optical axis, and
  • k denotes the conic constant,
  • wherein
  • c can be, e.g., in a range of about 0.0152 mm−1 to about 0.0659 mm−1,
  • r can be, e.g., in a range of about 0 to about 5, and
  • k can be, e.g., in a range of about −1162 to about −19 (e.g., in a range of about −73 to about −27).
  • In a related aspect, the optic of the above lens can have a shape factor in a range of about 0 to about 2.
  • In some embodiments in which one or more surfaces of the ophthalmic lens exhibit asphericity, the shape factor of the lens (e.g., an IOL) can be selected as a function of that asphericity so as to optimize the lens's optical performance. By way of example, in one aspect, the invention provides an ophthalmic lens having an optic with an anterior surface and a posterior surface, where at least one of the surfaces exhibits an ashperical profile characterized by a conic constant in a range of about −73 to about −27. The optic exhibits a shape factor in a range of about −0.5 to about 4.
  • In a related aspect, an ophthalmic lens having an optic with a shape factor in a range of about 0 to about 2 includes at least one aspherical surface characterized by a conic constant in a range of about −73 to about −27.
  • In other aspects, an intraocular lens adapted for implantation in an eye having a corneal radius equal to or less than about 7.1 mm is disclosed, which includes an optic having an anterior surface and a posterior surface. The optic exhibits a shape factor in a range of about −0.5 to about 4. In a related aspect, the optic exhibits a shape factor in a range of about +0.5 to about 4, or in a range of about 1 to about 3.
  • In another aspect, the invention provides an intraocular lens adapted for implantation in an eye having a corneal radius in a range of about 7.1 mm to about 8.6 mm, which includes an optic having an anterior surface and a posterior surface. The optic exhibits a shape factor in a range of about 0 to about 3. In a related aspect, the optic exhibits a shape factor in a range of about +0.5 to about 3, or in a range of about 1 to about 2.
  • In another aspect, an intraocular lens adapted for implantation in an eye having a corneal radius equal to or greater than about 8.6 is disclosed, which includes an optic having an anterior surface and a posterior surface. The optic exhibits a shape factor in a range of about 0.5 to about 2. In a related aspect, the optic exhibits a shape factor in a range of about 1 to about 2.
  • In another aspect, the invention provides an intraocular lens adapted for implantation in an eye having an axial length equal to or less than about 22 mm, which includes an optic having an anterior surface and a posterior surface. The optic can have a shape factor in a range of about 0 to about 2, or in a range of about 0.5 to about 2.
  • In other aspects, the invention discloses methods for selecting an ophthalmic lens for implantation in a patient's eye based on one or more ocular biometric parameters of the patient. For example, a method of correcting vision is disclosed that includes selecting an IOL, which comprises an optic exhibiting a shape factor in a range of about −0.5 to about 4 (or in a range of about +0.5 to about 4), for implantation in an eye having a corneal radius that is equal to or less than about 7.1 mm.
  • In another aspect, a method of correcting vision is disclosed that includes selecting an IOL, which comprises an optic exhibiting a shape factor in a range of about 0 to about 3 (or in a range of about 0.5 to about 3), for implantation in an eye having a corneal radius in a range of about 7.1 mm to about 8.6 mm.
  • In yet another aspect, a method of correcting vision is disclosed that includes selecting an IOL, which comprises an optic exhibiting a shape factor in a range of about 0.5 to about 2, for implantation in an eye having a corneal radius that is equal to or greater than about 8.6 mm.
  • In another aspect, a method of corrected vision is disclosed that includes selecting an IOL, which comprises an optic exhibiting a shape factor in a range of about 0 to about 2 (or in a range of about 0.5 to about 2), for implantation in an eye having an axial length equal to or less than about 22 mm.
  • In another aspect, a method of designing an ophthalmic lens is disclosed that includes defining an error function, which is indicative of variability in performance of a lens in a patient population, based on estimated variability in one or more biometric parameters associated with that population, and selecting a shape factor for the lens that reduces the error function relative to a reference value. In a related aspect, the error function can further include an estimated error in optical power correction provided by the lens and/or an estimated aberration error.
  • In a related aspect, the error function (RxError) can be defined in accordance with the following relation: RxError = Δ Biometric 2 + Δ IOLPower 2 + Δ Aberration 2
  • wherein,
  • ΔBiometric denotes variability due to biometric data errors,
  • ΔIOLPower denotes variability due to optical power correction errors, and
  • ΔAberration denotes variability due to aberration contributions.
  • In another aspect, the ΔBiometric can be defined in accordance with the following relation:
    ΔBiometric=√{square root over (Δk 2 +ΔAL 2 +ΔACD 2)}
  • wherein,
  • Δk denotes error in keratometric measurements,
  • ΔAL denotes error in axial length measurements, and
  • ΔACD denotes error in anterior chamber depth measurements.
  • In another aspect, the ΔAberration can be defined in accordance with the following relation:
    ΔAberration=√{square root over (ΔAstig2 +ΔSA 2+ΔOther2)}
  • wherein,
  • ΔAstig represents variability due to astigmatic aberration,
  • ΔSA represents variability due to spherical aberration, and
  • ΔOther represents variability due to other aberrations.
  • In a further aspect, the ΔIOLPower can be defined in accordance with the following relation:
    ΔIOLPower=√{square root over (ΔIOLStep2 +ΔIOLTol2 +ΔELP 2)}
  • wherein,
      • ΔIOLStep represents variability caused by difference between a power correction provided by the lens and a power correction needed by a patient,
      • ΔIOLTol represents manufacturing power tolerance, and
      • ΔELP represents variability in a shift of the lens effective position within the eye.
  • Further understanding of the invention can be obtained by reference to the following detailed description, in conjunction with the associated drawings, which are discussed briefly below.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a schematic side view of an IOL in accordance with one embodiment of the invention,
  • FIG. 2 presents simulated magnitude of different aberration types (spherical, defocus, coma and astigmatic aberrations) exhibited by an IOL as a function of its shape factor for a 1.5 mm decentration,
  • FIG. 3 presents simulation results for aberrations exhibited by an IOL due to tilt as a function of the IOL's shape factor,
  • FIG. 4A presents graphically calculated spherical aberration exhibited by a model eye characterized by an average anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 4B presents graphically calculated MTFs at 50 lp/mm and 100 lp/mm for a model eye characterized by an average anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 5A depicts simulated MTFs at 50 lp/mm and 100 lp/mm for a model eye characterized by a small anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 5B depicts simulated spherical aberration exhibited by a model eye characterized by a small anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 6A depicts simulated spherical aberration exhibited by a model eye characterized by a large anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 6B depicts simulated MTFs at 50 lp/mm and 100 lp/mm for a model eye characterized by a large anterior chamber depth in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 7A depicts graphically simulated spherical aberrations exhibited by a plurality of model eyes having different corneal asphericities in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 7B depicts graphically simulated MTF as 50 lp/mm obtained for model eyes having different corneal asphericities in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 7C depicts graphically simulated MTF at 100 lp/mm obtained for model eyes having different corneal asphericities in which an IOL is incorporated, as a function of the IOL's shape factor,
  • FIG. 8A depicts simulated spherical aberration exhibited by two model eyes characterized by different corneal radii as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 8B depicts simulated MTF at 50 lp/mm exhibited by two model eyes characterized by different corneal radii as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 8C depicts simulated MTF at 100 lp/mm exhibited by two model eyes characterized by different corneal radii as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 9A depicts simulated spherical aberration exhibited by a plurality of model eyes having different axial lengths as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 9B depicts simulated MTFs at 50 lp/mm exhibited by a plurality of model eyes having different axial lengths as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 9C depicts simulated MTFs at 100 lp/mm exhibited by a plurality of model eyes having different axial lengths as a function of the shape factor of an IOL incorporated in the models,
  • FIG. 10 is a schematic side view of a lens according to one embodiment of the invention having an aspheric anterior surface,
  • FIG. 11 presents a plurality of graphs depicting the sag of an aspheric surface of two lenses in accordance with the teachings of the invention having different shape factors, and
  • FIG. 12 graphically presents Monte Carlo simulation results for optical performance of a plurality of IOLs as a function of manufacturing tolerances.
  • DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • FIG. 1 schematically depicts an IOL 10 in accordance with one embodiment of the invention having an optic 12 that includes an anterior surface 14 and a posterior surface 16. In this embodiment, the anterior and posterior surfaces 14 and 16 are symmetrically disposed about an optical axis 18, though in other embodiments one or both of those surfaces can exhibit a degree of asymmetry relative to the optical axis. The exemplary IOL 10 further includes radially extending fixation members or haptics 20 that facilitate its placement in the eye. In this embodiment, the optic is formed of a soft acrylic polymer, commonly known as Acrysof, though in other embodiments, it can be formed of other biocompatible materials, such as silicone or hydrogel. The lens 10 provides a refractive optical power in a range of about 6 to about 34 Diopters (D), and preferably in a range of about 16 D to about 25 D.
  • In this exemplary embodiment, the lens 10 has a shape factor in a range of about 0 to about 2. More generally, in many embodiments, the shape factor of the lens 10 can range from about −0.5 to about 4. As known in the art, the shape factor of the lens 10 can be defined in accordance with the following relation: Shape Factor ( X ) = C 1 + C 2 C 1 - C 2 Eq . ( 1 )
    wherein C1 and C2 denote, respectively, the curvatures of the anterior and posterior surfaces.
  • The shape factor of the IOL 10 can affect the aberrations (e.g., spherical and/or astigmatic aberrations) that the lens can introduce as a result of its tilt and decentration, e.g., when implanted in the subject's eye or in a model eye. As discussed in more detail below, aberrations caused by a plurality of IOLs with different shape factors were theoretically studied as a function of tilt and decentration by utilizing a model eye. Those studies indicate that IOLs having a shape factor in a range of about 0 to about 2 introduce much reduced aberrations as a result of tilt and decentration.
  • More particularly, to study the effects of an IOL's shape factor on aberrations induced by its tilt and decentration, a hypothetical eye model having optical properties (e.g., corneal shape) similar to those of an average human eye was employed. The radii of optical surfaces and the separations between optical components were chosen to correspond to mean values of those parameters for the human population. The refractive indices of the optical components were chosen to provide selected refractive power and chromatic aberrations. Further, the anterior corneal surface of the model was selected to have an ashperical shape. An IOL under study replaced the natural lens in the model. Table 1 below lists the various design parameters of the model eye:
    TABLE 1
    Thick- Dia-
    Radius ness meter Conic
    Surface Type (mm) (mm) Class (mm) Constant
    OBJ Standard Infinity Infinity 0.000 0.000
    1 Standard Infinity 10.000 5.000 0.000
    2 Standard 7.720 0.550 Cornea 14.800 −0.260
    3 Standard 6.500 3.050 Aqueous 12.000 0.000
    STO Standard Infinity 0.000 Aqueous 10.000 0.000
    5 Standard 10.200 4.000 Lens 11.200 −3.132
    6 Standard −6.000 16.179 Vitreous 11.200 −1.000
    IMA Standard −12.000 24.000 0.000
  • An optical design software marketed as Zemax® (version Mar. 4, 2003, Zemax Development Corporation, San Diego, Calif.) was utilized for the simulations of the optical properties of the model eye. A merit function was defined based on the root-mean-square (RMS) wavefront aberration, that is, the RMS wavefront deviation of an optical system from a plane wave. In general, the larger the RMS wavefront error, the poorer is the performance of the optical system. An optical system with an RMS wavefront error that is less than about 0.071 waves is typically considered as exhibiting a diffraction-limited optical performance.
  • The effects of misalignment (tilt and/or decentration) of an IOL on its optical performance for a number of different shape factors was simulated by placing the IOLs in the above model eye and utilizing the Zemax® software. For these simulations, the IOL was assumed to have spherical surfaces so as to investigate the effects of the shape factor alone (as opposed to that of the combined shape factor and asphericity). To simulate the scotopic viewing conditions for old patients, a 5 mm entrance pupil was chosen. The following misalignment conditions were considered: 1.5 mm IOL decentration and a 10-degree IOL tilt. These two conditions represent the extreme cases of IOL misalignments.
  • FIG. 2 presents the simulated magnitude of different aberration types (spherical aberration, defocus, coma and astigmatism) as a function of the shape factor for 1.5 mm decentration of the IOL. These simulations indicate that IOLs with a shape factor in a range of about 0 to about 2 exhibit much lower aberrations as a result of the decentration. For example, an IOL with a shape factor of about 1 introduces a defocus aberration of 0.07 D compared to a defocus aberration of 0.32 D introduced by an IOL having a shape factor of −1.
  • FIG. 3 presents the simulation results for aberrations introduced as a result of the IOL's tilt. These results indicate that the defocus and astigmatic aberrations are not significantly influenced by the IOL's shape factor while the coma and spherical aberrations exhibit even stronger dependence on the shape factor than their dependence in case of the IOL's decentration. Again, the IOLs with shape factors in a range of about 0 to 2 exhibit a stable performance.
  • In other aspects, it has been discovered that certain biometric parameters of the eye (e.g., corneal radius and axial length) can be considered while selecting the shape factor of an IOL for implantation in the eye to provide enhanced performance of the lens. As discussed in more detail below, in some embodiments, optimal IOL shape factors are provided for different eye populations, e.g., average human eye (eyes with average values for certain biometric parameters), and other populations characterized by extreme values for those parameters.
  • The biometric parameters of the above eye model were varied to simulate the performance of a plurality of IOLs having different shape factors for different eyes. For an average human eye, a corneal radius (r) of 7.72 mm, a corneal asphericity (Q) of −0.26, an anterior chamber depth (ACD) of 4.9 mm, and an axial length (AL) of 24.4 mm were assumed. To investigate human eyes with extreme large or small biometric values, the anterior chamber depth was varied from 4.3 mm to 5.5 mm, the corneal asphericity was varied from −0.50 to 0, the corneal radius was varied from 7.10 mm to 8.60 mm, and the axial length was varied from 22.0 mm to 26.0 mm. These ranges are sufficiently broad to cover the values exhibited by the majority of the population. The optical performance of the IOLs was evaluated based on two criteria: calculated wave aberration and modulation transfer function (MTF). As known to those having ordinary skill in the art, the MTF provides a quantitative measure of image contrast exhibited by an optical system, e.g., a system formed of an IOL and the cornea. More specifically, the MTF of an imaging system can be defined as a ratio of a contrast associated with an image of an object formed by the optical system relative to a contrast associated with the object.
  • Table 2 below presents the simulation results of the optical performance of IOLs having shape factors in a range of about −2 to about 4 for an eye having an average anterior chamber depth (ACD) of 4.9 mm, a corneal radius of 7.72 mm, a corneal asphericity of −0.26, and an axial length (AL) of 24.4 mm, at a pupil size of 5 mm.
    TABLE 2
    Shape Spherical
    Factor (X) Aberration (SA) MTF at 50 lp/mm MTF at 100 lp/mm
    −2 0.478 0.037 0.095
    −1.5 0.386 0.117 0.051
    −1 0.307 0.212 0.011
    −0.5 0.244 0.331 0.016
    0 0.195 0.455 0.128
    0.5 0.162 0.555 0.250
    1 0.142 0.615 0.334
    1.5 0.134 0.637 0.366
    2 0.138 0.625 0.348
    3 0.174 0.516 0.199
    4 0.239 0.340 0.021
  • For graphical presentation of the information in Table 2, FIGS. 4A and 4B provide, respectively, the calculated spherical aberration and MTF presented in Table 1 as a function of IOL's shape factor.
  • Table 3 below presents the simulation results for the optical performance of a plurality of IOLs having shape factors in the above range of −2 to 4 at a pupil size of 5 mm for an eye having a small anterior chamber depth (ACD) of 4.3 mm, but the same corneal radius (7.72 mm) and asphericity (−0.26) as well as axial length (24.4 mm) as that employed in the previous simulation. FIGS. 5A and 5B graphically depict, respectively, the calculated spherical aberration (SA) and the MTF presented in Table 3 as a function of the IOL's shape factor.
    TABLE 3
    Shape Sph. Aberration
    Factor (X) (waves) MTF at 50 lp/mm MTF at 100 lp/mm
    −2 0.461 0.047 0.095
    −1.5 0.374 0.125 0.042
    −1 0.300 0.219 0.014
    −0.5 0.240 0.337 0.021
    0 0.194 0.457 0.130
    0.5 0.161 0.553 0.249
    1 0.141 0.613 0.331
    1.5 0.133 0.636 0.365
    2 0.136 0.627 0.353
  • Table 4 below presents the simulation results for the optical performance of a plurality of IOLs having shape factors in the above range of −2 to 4 at a pupil size of 5 mm for an eye having a large anterior chamber depth (ACD) of 5.5 mm, a corneal radius of 7.72 mm, a corneal asphericity of −0.26 and an axial length of 24.4 mm. Further, FIGS. 6A and 6B graphically depict, respectively, the calculated spherical aberration (SA) and the MTF presented in Table 4 as a function of the IOL's shape factor.
    TABLE 4
    Shape Sph. Aberration
    Factor (X) (waves) MTF at 50 lp/mm MTF at 100 lp/mm
    −2 0.498 0.026 0.093
    −1.5 0.399 0.108 0.059
    −1 0.316 0.204 0.008
    −0.5 0.249 0.325 0.011
    0 0.198 0.454 0.125
    0.5 0.162 0.556 0.251
    1 0.142 0.617 0.336
    1.5 0.135 0.637 0.365
    2 0.140 0.622 0.342
  • These simulations indicate that IOLs with shape factors in a range of about −0.5 to about 4, and particularly those having shape factors in a range of about 0 to about 2, provide enhanced optical performance. The simulations, however, show that anterior chamber depth does not significantly affect the performance of an IOL.
  • Although in the afore-mentioned simulations the spherical aberrations were considered, in the IOL is misaligned relative to the cornea, other aberrations (e.g., defocus, astigmatism and coma) can also be present. The simulations of these aberrations for average, small and large ACD confirm that the aberrations can be minimized by utilizing shape factors in a range about 0 to about 2.
  • The impact of corneal asphericity (Q) on optimal IOL shape factor was also investigated by utilizing the aforementioned eye model and calculating spherical aberration and MTF for Q-=0 (spherical), Q=−0.26 and Q=−0.50. The more negative the Q value, the flatter is the peripheral portion of the cornea. Q=−0.26 corresponds to the asphericity of the normal human cornea while Q=−0.50 corresponds to the asphericity of an extremely flat cornea. Table 5 below lists the results of these simulations, with FIGS. 7A, 7B and 7C graphically depicting, respectively, the simulated spherical aberration, the MTF at 50 lp/mm and the MTF at 100 lp/mm as a function of the IOL's shape factor.
    TABLE 5
    SA (micron) MTF@501 p/mm MTF@1001 p/mm
    X Q = 0 Q = −0.26 Q = −0.50 Q = 0 Q = −0.26 Q = −50 Q = 0 Q = −0.26 Q = −0.50
    −2 0.609 0.478 0.364 0.000 0.037 0.143 0.036 0.095 0.027
    −1.5 0.524 0.386 0.264 0.010 0.117 0.292 0.084 0.051 0.007
    −1 0.451 0.307 0.180 0.058 0.212 0.503 0.091 0.011 0.182
    −0.5 0.392 0.244 0.112 0.111 0.331 0.702 0.057 0.016 0.463
    0 0.347 0.195 0.061 0.159 0.455 0.822 0.016 0.128 0.661
    0.5 0.315 0.162 0.025 0.200 0.555 0.869 0.007 0.250 0.742
    1 0.295 0.142 0.005 0.230 0.615 0.879 0.012 0.334 0.759
    1.5 0.288 0.134 0.002 0.243 0.637 0.879 0.012 0.366 0.759
    2 0.29 0.138 0.003 0.238 0.625 0.879 0.013 0.348 0.759
    3 0.321 0.174 0.045 0.189 0.516 0.848 0.004 0.199 0.704
    4 0.378 0.239 0.117 0.120 0.340 0.688 0.046 0.021 0.443
  • The spherical aberration exhibited by a spherical cornea (Q=0) is significantly larger than those exhibited by the aspherical corneas (Q=−0.26 and Q=−0.50), as expected. As a result, the MTFs associated with Q=0 are lower than those for Q=−0.26 and Q=−0.50. However, for each of the three cases, the above simulations indicate that an optimal IOL shape factor lies in a range of about −0.5 to about 4, and preferably in a range of about 0 to about 2.
  • In another set of simulations, the effect of corneal radius on optimal shape factor was investigated. Table 6 below presents the simulation results corresponding to spherical aberration as well as MTFs at 50 lp/mm and 100 lp/mm obtained for a plurality of IOLs having shape factors in a range of about −2 to about 8 by utilizing the afore-mentioned eye model and varying the corneal radius. More specifically, the ACD, Q and AL were fixed, respectively, at 4.9 mm, −0.26, and 24.4 mm while the corneal radius was varied. FIGS. 8A, 8B and 8C graphically depict, respectively, variations of the spherical aberration, the MTF at 50 lp/mm and the MTF at 100 lp/mm in these simulations as a function of the IOL's shape factor for two different radii.
    TABLE 6
    r
    SA (waves) MTF@501 p/mm MTF@1001 p/mm
    r = 7.10 r = 7.72 r = 8.60 r = 7.10 r = 7.72 r = 8.60 r = 7.10 r = 7.72 r = 8.60
    X mm mm mm mm mm mm mm mm mm
    −2 0.312 0.478 0.856 0.196 0.037 0.086 0.010 0.095 0.031
    −1.5 0.282 0.386 0.635 0.245 0.117 0.00 0.015 0.051 0.032
    −1 0.255 0.307 0.447 0.297 0.212 0.07 0.002 0.011 0.086
    −0.5 0.233 0.244 0.300 0.347 0.331 0.234 0.029 0.016 0.011
    0 0.215 0.195 0.195 0.393 0.455 0.468 0.067 0.128 0.139
    0.5 0.201 0.162 0.133 0.432 0.555 0.65 0.105 0.250 0.382
    1 0.190 0.142 0.111 0.463 0.615 0.711 0.139 0.334 0.476
    1.5 0.182 0.134 0.127 0.485 0.637 0.667 0.165 0.366 0.408
    2 0.177 0.138 0.174 0.499 0.625 0.528 0.182 0.348 0.210
    3 0.175 0.174 0.344 0.503 0.516 0.173 0.188 0.199 0.008
    4 0.182 0.239 0.579 0.483 0.340 0.008 0.163 0.021 0.062
    5 0.195 0.444 0.118
    6 0.213 0.394 0.067
    7 0.234 0.339 0.022
    8 0.258 0.285 0.007
  • These simulations indicate that for a very steep cornea (e.g., a corneal radius of 7.1 mm), the IOL's shape factor has a relatively small impact on the spherical aberration and the MTF. For example, in such a case, for shape factors in a wide range of about −1 to about 8, good optical performance is observed, though shape factors in a range of about 0.5 to about 4 are preferred. However, for a cornea having a large radius, e.g., a radius larger than about 8.6 mm, an optimal range of about 0 to about 2 (e.g., about 0.5 to about 2) for the IOL's shape factor is observed. The peak of the IOL's optical performance as a function of the shape factor also shifts as the corneal radius varies from a small value to a large one. For example, the simulations indicate a peak performance at a shape factor of about 3 for a cornea with a radius of about 7.1 mm and at a shape factor of about 1 for a cornea with a radius of about 8.6 mm.
  • Similar to corneal radius, it was discovered that an optimal shape factor for an IOL can vary as a function of the eye's axial length. By way of example, Table 7 below presents the results of simulations for optical performance of a plurality of IOLs having shape factors in a range of −2 to 8 for a plurality of different axial lengths (ALs). The model eye utilized for these simulations was characterized by an ACD=4.9 mm, a corneal radius (r)=7.72 mm, and a corneal asphericity (Q)=−0.26. The graphical representation of these simulations are provided in FIGS. 9A, 9B and 9C for spherical aberration, MTF at 50 lp/mm and MTF at 100 lp/mm, respectively.
    TABLE 7
    SA (micron) MTF@501 p/mm MTF@1001 p/mm
    AL = 22.0 AL = 24.4 AL = 26.0 AL = 22.0 AL = 24.4 AL = 26.0 AL = 22.0 AL = 24.4 AL = 26.0
    X mm mm mm mm mm mm mm mm mm
    −2 0.478 0.285 0.037 0.209 0.095 0.021
    −1.5 0.386 0.117 0.051
    −1 0.609 0.307 0.215 0.000 0.212 0.364 0.078 0.011 0.047
    −0.5 0.244 0.331 0.016
    0 0.281 0.195 0.166 0.322 0.455 0.507 0.015 0.128 0.200
    0.5 0.162 0.555 0.250
    1 0.168 0.142 0.138 0.591 0.615 0.596 0.284 0.334 0.318
    1.5 0.134 0.637 0.366
    2 0.240 0.138 0.127 0.407 0.625 0.629 0.070 0.348
    3 0.441 0.174 0.132 0.122 0.516 0.616 0.054 0.199 0.345
    4 0.718 0.239 0.147 0.011 0.340 0.565 0.030 0.021 0.275
    5 0.171 0.488 0.176
    6 0.202 0.395 0.075
    7 0.237 0.302 0.001
    8 0.274 0.222 0.024
  • The above simulations indicate that while for a long axial length (e.g., an axial length of about 26 mm), IOLs having shape factors over a wide range (e.g., in a range of about −1 to about 8) provide substantially similar performance, for a short axial length (e.g., an axial length of about 22 mm), an optimal IOL shape factor lies in a range of about 0 to about 2 (preferably in a range of about 0.5 to about 2). Further, the peak of optical performance exhibits a shift as a function of axial length variation.
  • In some embodiments, an anterior or a posterior surface of the IOL includes an aspherical base profile selected to compensate for the corneal spherical aberration. Alternatively, both anterior and posterior surfaces can be aspherical so as to collectively provide a selected degree of compensation for the corneal spherical aberration. By way of example, FIG. 10 shows an IOL 22 according to one embodiment of the invention that includes an optic having a spherical posterior surface 24 and an aspherical anterior surface 26. More specifically, the anterior surface 26 is characterized by a base profile that is substantially coincident with a putative spherical profile 26 a (shown by dashed lines) for small radial distances from an optical axis 28 but deviates from that spherical profile as the radial distance from the optical axis increases. In this embodiment, the aspherical anterior surface can be characterized by the following relation: z = cr 2 1 + 1 - ( 1 + k ) c 2 r 2 Eq . ( 2 )
    wherein,
  • c denotes the curvature of the surface at its apex (at its intersection with the optical axis),
  • r denotes the radial distance from the optical axis, and
  • k denotes the conic constant.
  • In some embodiments, the conic constant k can range from about −1162 to about −19 (e.g., from about −73 to about −27) and the shape factor of the lens can range from about −0.5 to about 4, and more preferably, from about 0 to about 2. To show the efficacy of such aspherical IOLs in reducing the corneal spherical aberrations, two aspherical IOLs were theoretically designed. The IOLs were assumed to be formed of an acrylic polymer commonly known as Acrysof. One of the IOLs was selected to have a shape factor of zero (X=0) while the other was chosen to have a shape factor of 1 (X=1). The edge thickness for each IOL was fixed at 0.21 mm. For the IOL with X=0, the anterior and posterior radii were set, respectively, at 22.934 mm and −22.934 mm, the central thickness was set at 0.577 mm and the anterior surface asphericity (i.e., the conic constant) was selected to be −43.656. For the IOL with X=1, the posterior surface was selected to be flat while the radius of the anterior surface was set at 11.785 mm. The central thickness of this lens was 0.577 mm and the anterior surface was assumed to have an asphericity characterized by a conic constant of −3.594. FIG. 11 shows the sag of the anterior surfaces of these exemplary IOLs as a function of radial distance from the optical axis.
  • The simulations of the optical performances of these two IOL designs in the aforementioned eye model show a reduction of the total RMS wavefront errors to about 0.000841 waves in case of the IOL having a shape factor that approaches zero and to about 0.000046 in case of the IOL having a shape factor of unity.
  • Another factor that can affect the optical performance of an IOL is its effective position. The effective lens position (e.g., defined here as the location of the principal plane relative to the posterior surface) can vary as a function of the lens's shape. The location of the second principal plane (PP2) relative to the apex of the posterior surface can be defined by the following relation: PP 2 = - n 1 dF 1 n 2 F L Eq . ( 3 )
    wherein n1 and n2 denote, respectively, the refractive indices of the IOL and the surrounding medium, F1 represents the optical power of the anterior surface and F2 represents the optical power of the lens, and d is the lens's central thickness. The haptics plane (the anchor plane for the implanted IOL) located at the central-line of the lens edge can have a distance from the apex of the posterior surface specified as: HL = Sag 2 + ET 2 Eq . ( 4 )
    wherein ET denotes the lens's edge thickness and Sag2 denotes the sag height of the posterior surface at the lens's edge. Utilizing the above Equations (3) and (4), the location of the second principal point relative to the haptics plane can be defined as follows: Δ PP 2 = Sag 2 + ET 2 - n 1 dF 1 n 2 F L Eq . ( 5 )
    wherein ΔPP2 denotes an offset shift of the principal plane, and the other parameters are defined above.
  • By way of example, the 2nd principal plane shift for the aforementioned IOL having a shape factor of zero (X=0) was calculated (by utilizing the above equations) across a power range of 0 to about 35 D as +/−0.03 mm, while the corresponding shift for the IOL having a shape factor of unity (X=1) was calculated as +/−0.15 mm.
  • To better appreciate the enhanced optical performance provided by the IOLs of the invention, some of the major factors contributing to the variability of post-operative refractive errors can be considered. These factors are generally classified into three categories: biometric data errors (ΔBiometric), IOL power errors (ΔIOLPower) and high-order aberration contributions (ΔAberration). An overall variability (Rx) can be calculated based on these factors by utilizing, e.g., the following relation: RxError = Δ Biometric 2 + Δ IOLPower 2 + Δ Aberration 2 Eq . ( 6 )
  • The ΔBiometric can, in turn, be defined in accordance with the following relation:
    ΔBiometric=√{square root over (Δk 2 +ΔAL 2 +ΔACD 2)}  Eq. (7)
    wherein Δk denotes the error in keratometric measurement, ΔAL denotes the error in axial length measurement, and ΔACD denotes the error in the anterior chamber depth measurement. The ΔIOLPower can be defined in accordance with the following relation:
    ΔIOLPower=√{square root over (ΔIOLStep2 +ΔIOLTol2 +ΔELP 2)}  Eq. (8)
    wherein ΔIOLStep denotes the variability caused by the use of IOLs whose optical powers differ by finite steps for correcting patients' refractive errors that vary over a continuous range, ΔIOLTol denotes manufacturing power tolerance, and ΔELP denotes the variability in the shift of the IOL effective position across the power range. Further, ΔAberration can be defined in accordance with the following relation:
    ΔAberration=√{square root over (ΔAstig2 +ΔSA 2+ΔOther2)}  Eq. (9)
    wherein ΔAstig, ΔSA, ΔOther denote, respectively, astigmatic, spherical and other higher order aberrations.
  • The optical performance of the aforementioned exemplary IOL designs having shape factors (X) of zero and unity were evaluated based on estimated Rx variability for three conditions: (1) uncorrected visual acuity (i.e., in the absence of corrective spectacles) with IOL power step of 0.5 D (UCVA), (2) uncorrected visual acuity with a refined IOL power step of 0.25 D (UCVA+) and (3) best corrected visual acuity (i.e., utilizing optimal corrective spectacles) (BCVA). The variability due to biometric measurements was estimated from information available in the literature. The focus of the analysis relates to estimating contributions of the spherical aberration, errors due to IOL misalignments, and the 2nd principal plane (PPL) shifts. For comparison purposes, a baseline value of 0.65 D was assumed for UCVA and UCVA+ and a baseline value of 0.33 D was assumed for BCVA, for eyes with spherical IOLs. Table 8 below lists absolute and percentage reductions in Rx relative to the baseline values for the two IOLs:
    TABLE 8
    IOL with X = 0 IOL with X = 1
    UCVA −0.03 D −4.39%   0.00 D 0.45%
    UCVA+ −0.05 D −7.13% −0.01 D −2.16%
    BCVA −0.03 D −8.53% −0.05 D −13.87%
  • The information presented in Table 8 shows that reductions in Rx variability are achieved for both IOLs (X=0, and X=1), thus indicating improved optical performance of those lenses. For the IOL with a vanishing shape factor (X=0), the visual benefits are almost evenly distributed among UCVA, UCVA+ and BCVA while for the other IOL (X=1), the visual benefit associated with BCVA is more pronounced.
  • A variety of known manufacturing techniques can be employed to fabricate the lenses of the invention. The manufacturing tolerances can also affect the optical performance of an IOL. By way of example, such tolerances can correspond to variations of, e.g., surface radii, conic constant, surface decentration, surface tilt, and surface irregularity, with tolerances associated with surface asphericity (conic constant) generally playing a more important role that others in affecting optical performance. Simulations, however, indicate that the IOL's misalignments upon implantation in the eye are typically more significant factors in degrading optical performance than manufacturing tolerances (e.g., manufacturing errors can be nearly 10 times less than misalignment errors). By way of further illustration, the optical performance of the aforementioned aspherical lenses with X=0 and X=1, implanted in the aforementioned eye model, was theoretically investigated by employing Monte Carlo simulations. More specifically, 500 hypothetical lenses were generated under constraints of typical manufacturing tolerances and were randomly oriented relative to the cornea. For example, the tolerances associated with the surface radii, surface irregularities, and surface decentration and tilt were assumed to be, respectively, within +/−0.1 mm, 2 fringes, 0.05 mm and 0.5 degrees. The results of the Monte Carlo simulations are summarized in FIG. 12. More than 50% of the simulated eyes exhibit an RMS wavefront error that is less than about 0.2 waves (about 0.08 D equivalent defocus). For the lens having X=1, about 98% of the simulated eyes show a wavefront error less than about 0.3 waves (about 0.12 D).
  • Those having ordinary skill in the art will appreciate that various changes can be made to the above embodiments without departing from the scope of the invention.

Claims (42)

  1. 1. An ophthalmic lens, comprising
    an optic having an anterior surface and a posterior surface,
    said optic exhibiting a shape factor in a range of about −0.5 to about 4.
  2. 2. The ophthalmic lens of claim 1, wherein said optic exhibits a shape factor in a range of about 0 to about 2.
  3. 3. The ophthalmic lens of claim 1, wherein said optic comprises a biocompatible polymeric material.
  4. 4. The ophthalmic lens of claim 3, wherein the polymeric material is selected from the group consisting of acrylic, silicone and hydrogel materials.
  5. 5. The ophthalmic lens of claim 1, wherein both of said surfaces have a generally convex profile.
  6. 6. The ophthalmic lens of claim 1, wherein one of said surfaces has a generally convex profile and the other surface has a substantially flat profile.
  7. 7. The ophthalmic lens of claim 1, wherein one of said surfaces has a generally concave profile and the other surface has a substantially flat profile.
  8. 8. The ophthalmic lens of claim 1, wherein one of said surfaces has a generally concave profile and the other surface has a generally convex profile.
  9. 9. The ophthalmic lens of claim 1, wherein at least one of said surfaces is characterized by an aspherical base profile.
  10. 10. The ophthalmic lens of claim 9, wherein said aspheric base profile is characterized by a conic constant (Q) in a range of about −73 to about −27.
  11. 11. The ophthalmic lens of claim 1, wherein said lens comprises an intraocular lens.
  12. 12. An ophthalmic lens, comprising
    an optic having an anterior surface and a posterior surface,
    at least one of said surfaces being characterized by an aspherical base profile defined by the following relation:
    z = c r 2 1 + 1 - ( 1 + k ) c 2 r 2
    wherein,
    c denotes the curvature of the surface at its apex (at its intersection with the optical axis),
    r denotes the radial distance from the optical axis, and
    k denotes the conic constant,
    wherein
    c is in a range of about 0.0152 mm−1 to about 0.0659 mm−1,
    r is in a range of about 0 to about 5 mm, and
    k is in a range of about −73 to about −27,
    wherein said optic exhibits a shape factor in a range of about −0.5 to about 4.
  13. 13. The ophthalmic lens of claim 12, wherein said optic exhibits a shape factor in a range of about 0 to about 2.
  14. 14. The ophthalmic lens of claim 12, wherein said lens comprises an intraocular lens.
  15. 15. The ophthalmic lens of claim 12, wherein said surfaces cooperatively provide a refractive optical power in a range of about 16 D to about 25 D.
  16. 16. The ophthalmic lens of claim 12, wherein said optic is formed of a biocompatible polymeric material.
  17. 17. An intraocular lens adapted for implantation in an eye having a corneal radius equal to or less than about 7.1 mm, comprising
    an optic having an anterior surface and a posterior surface,
    said optic exhibiting a shape factor in a range of about −0.5 to about 4.
  18. 18. The intraocular lens of claim 17, wherein optic exhibits a shape factor in a range of about +0.5 to about 4.
  19. 19. The intraocular lens of claim 17, wherein said optic exhibits a shape factor in a range of about 1 to about 3.
  20. 20. An intraocular lens adapted for implantation in an eye having a corneal radius in a range of about 7.1 to about 8.6 mm, comprising
    an optic having an anterior surface and a posterior surface,
    said optic exhibiting a shape factor in a range of about 0 to about 3.
  21. 21. The intraocular lens of claim 20, wherein said optic exhibits a shape factor in a range of about +0.5 to about 3.
  22. 22. The intraocular lens of claim 20, wherein said optic exhibits a shape factor in a range of about 1 to about 2.
  23. 23. An intraocular lens adapted for implantation in an eye having a corneal radius equal to or greater than about 8.6 mm, comprising
    an optic having an anterior surface and a posterior surface,
    said optic exhibiting a shape factor in a range of about +0.5 to about 2.
  24. 24. The intraocular lens of claim 23, wherein said optic exhibits a shape factor in a range of about 1 to about 2.
  25. 25. An intraocular lens adapted for implantation in an eye having an axial length equal to or less than about 22 mm, comprising
    an optic having an anterior surface and a posterior surface,
    said optic having a shape factor in a range of about 0 to about 2.
  26. 26. The intraocular lens of claim 25, wherein the optic exhibits a shape factor in a range of about 0.5 to about 2.
  27. 27. An ophthalmic lens, comprising
    an optic having an anterior surface and a posterior surface,
    at least one of said surfaces having an aspherical profile characterized by a conic constant in a range of about −73 to about −27,
    wherein said optic exhibits a shape factor in a range of about −0.5 to about 4.
  28. 28. The ophthalmic lens of claim 27, wherein said aspherical profile is characterized by a conic constant in a range of about −73 to about −27, and said optic exhibits a shape factor in a range of about 0 to about 2.
  29. 29. A method of correcting vision, comprising
    selecting an IOL comprising an optic exhibiting a shape factor in a range of about −0.5 to about 4 for implantation in an eye having a corneal radius equal or less than about 7.1 mm.
  30. 30. The method of claim 29, wherein the shape factor of the optic is selected to be in a range of about +0.5 to about 4.
  31. 31. A method of correcting vision, comprising
    selecting an IOL comprising an optic exhibiting a shape factor in a range of about 0 to about 3 for implantation in an eye having a corneal radius in a range of about 7.1 mm to about 8.6 mm.
  32. 32. The method of claim 31, wherein the shape factor of the optic is selected to be in a range of about +0.5 to about 3.
  33. 33. A method of correcting vision, comprising
    selecting an IOL comprising an optic exhibiting a shape factor in a range of about 0.5 to about 2 for implantation in an eye having a corneal radius equal to or greater than about 8.6 mm.
  34. 34. A method of correcting vision, comprising
    selecting an IOL comprising an optic exhibiting a shape factor in a range of about 0 to about 2 for implantation in an eye having an axial length equal to or less than about 22 mm.
  35. 35. The method of claim 34, wherein a shape factor of the optic is selected to be in a range of about 0.5 to about 2.
  36. 36. A method of designing an ophthalmic lens, comprising
    defining an error function indicative of variability in performance of a lens in a patient population based on estimated variability in one or more biometric parameters associated with that population, and
    selecting a shape factor for the lens that reduces said error function relative to a reference value.
  37. 37. The method of claim 36, wherein said error function further incorporates an estimated error in optical power correction provided by the lens.
  38. 38. The method of claim 37, wherein said error function further incorporates an estimated aberration error.
  39. 39. The method of claim 38, wherein said error function (RxError) is defined by the following relation:
    RxError = Δ Biometric 2 + Δ IOLPower 2 + Δ Aberration 2
    wherein,
    ΔBiometric denotes variability due to biometric data errors,
    ΔIOLPower denotes variability due to optical power errors, and
    ΔAberration denotes variability due to aberration contributions.
  40. 40. The method of claim 39, wherein ΔBiometric is defined by the following relation:

    ΔBiometric=√{square root over (Δk 2 +ΔAL 2 +ΔACD 2)}
    wherein,
    Δk denotes error in keratometric measurements,
    ΔAL denotes error in axial length measurements, and
    ΔACD denotes error in anterior chamber depth measurements.
  41. 41. The method of claim 39, wherein ΔAberration is defined by the following relation:

    ΔAberration=√{square root over (ΔAstig2 +ΔSA 2+ΔOther2)}
    wherein,
    ΔAstig represents variability due to astigmatic aberration,
    ΔSA represents variability due to spherical aberration, and
    ΔOther represents variability due to other aberrations.
  42. 42. The method of claim 39, wherein ΔIOLPower is defined by the following relation:

    ΔIOLPower=√{square root over (ΔIOLStep2 +ΔIOLTol2 +ΔELP 2)}
    wherein,
    ΔIOLStep represents variability caused by difference between the lens power and a power need of a patient,
    ΔIOLTol represents manufacturing power tolerance, and
    ΔELP represents variability in a shift of the lens effective position within the eye.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100125331A1 (en) * 2008-11-19 2010-05-20 Simpson Michael J Aspheric intraocular lens with improved control of aberrations
WO2011153158A1 (en) * 2010-06-01 2011-12-08 Elenza, Inc. Implantable ophthalmic device with an aspheric lens
US20120069298A1 (en) * 2009-03-26 2012-03-22 Eugene Ng Ocular modeling methods and apparatus
WO2014111769A1 (en) 2013-01-15 2014-07-24 Medicem Ophthalmic (Cy) Limited Bioanalogic intraocular lens
US9146103B2 (en) * 2010-12-10 2015-09-29 Thales Apparatus and optical method of ranging and of high bit-rate communication
US9195074B2 (en) 2012-04-05 2015-11-24 Brien Holden Vision Institute Lenses, devices and methods for ocular refractive error
US9201250B2 (en) 2012-10-17 2015-12-01 Brien Holden Vision Institute Lenses, devices, methods and systems for refractive error
US9541773B2 (en) 2012-10-17 2017-01-10 Brien Holden Vision Institute Lenses, devices, methods and systems for refractive error
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Families Citing this family (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8020995B2 (en) 2001-05-23 2011-09-20 Amo Groningen Bv Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
US6609793B2 (en) * 2000-05-23 2003-08-26 Pharmacia Groningen Bv Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
EP1420722B1 (en) 2001-08-21 2010-12-01 Nulens Ltd Accommodating lens assembly
ES2665536T3 (en) 2004-04-20 2018-04-26 Alcon Research, Ltd. surgical microscope and integrated front sensor wave
CN101642392A (en) * 2004-04-29 2010-02-10 纽镜有限公司 Accommodating intraocular lens assemblies and accommodation measurement implant
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US8801781B2 (en) * 2005-10-26 2014-08-12 Abbott Medical Optics Inc. Intraocular lens for correcting corneal coma
WO2008023379A3 (en) * 2006-08-25 2008-04-17 Nulens Ltd Intraocular lens implantation kit
EP2102697A1 (en) * 2007-01-11 2009-09-23 Alcon Research, Ltd. Alternating optical system: mixing and matching optics to maximize binocular visual benefits
USD702346S1 (en) 2007-03-05 2014-04-08 Nulens Ltd. Haptic end plate for use in an intraocular assembly
US8273123B2 (en) * 2007-03-05 2012-09-25 Nulens Ltd. Unitary accommodating intraocular lenses (AIOLs) and discrete base members for use therewith
KR100807939B1 (en) * 2007-03-08 2008-02-28 박경진 Lens assembly
KR100807940B1 (en) * 2007-03-08 2008-02-28 박경진 Intraocular lens
US20090062911A1 (en) * 2007-08-27 2009-03-05 Amo Groningen Bv Multizonal lens with extended depth of focus
US8974526B2 (en) 2007-08-27 2015-03-10 Amo Groningen B.V. Multizonal lens with extended depth of focus
US9216080B2 (en) 2007-08-27 2015-12-22 Amo Groningen B.V. Toric lens with decreased sensitivity to cylinder power and rotation and method of using the same
US8747466B2 (en) * 2007-08-27 2014-06-10 Amo Groningen, B.V. Intraocular lens having extended depth of focus
US8740978B2 (en) 2007-08-27 2014-06-03 Amo Regional Holdings Intraocular lens having extended depth of focus
US20090059163A1 (en) * 2007-08-30 2009-03-05 Pinto Candido D Ophthalmic Lens Having Selected Spherochromatic Control and Methods
US20090088840A1 (en) * 2007-10-02 2009-04-02 Simpson Michael J Zonal diffractive multifocal intraocular lenses
US7594729B2 (en) 2007-10-31 2009-09-29 Wf Systems, Llc Wavefront sensor
EP2365379B1 (en) 2008-02-15 2016-01-27 AMO Regional Holdings Method of forming an ophthalmic lens for extending the depth of focus of an eye
US8439498B2 (en) 2008-02-21 2013-05-14 Abbott Medical Optics Inc. Toric intraocular lens with modified power characteristics
US8231219B2 (en) 2008-04-24 2012-07-31 Amo Groningen B.V. Diffractive lens exhibiting enhanced optical performance
US7871162B2 (en) 2008-04-24 2011-01-18 Amo Groningen B.V. Diffractive multifocal lens having radially varying light distribution
US8167940B2 (en) * 2008-05-06 2012-05-01 Novartis Ag Aspheric toric intraocular lens
US8241354B2 (en) * 2008-07-15 2012-08-14 Novartis Ag Extended depth of focus (EDOF) lens to increase pseudo-accommodation by utilizing pupil dynamics
JP5276165B2 (en) * 2008-07-24 2013-08-28 ニューレンズ・リミテッド Adjustable intraocular lens (AIOL) Capsule
EP2177179B1 (en) * 2008-10-15 2011-06-15 Carl Zeiss Meditec France S.A.S. Method for modelling an intraocular lens and intraocular lens
WO2010054268A3 (en) 2008-11-06 2016-03-31 Wavetec Vision Systems, Inc. Optical angular measurement system for ophthalmic applications and method for positioning of a toric intraocular lens with increased accuracy
US8216307B2 (en) * 2008-12-19 2012-07-10 Novartis Ag Radially segmented apodized diffractive multifocal design for ocular implant
US8876290B2 (en) 2009-07-06 2014-11-04 Wavetec Vision Systems, Inc. Objective quality metric for ocular wavefront measurements
KR101730675B1 (en) 2009-07-14 2017-05-11 웨이브텍 비젼 시스템스, 인크. Ophthalmic surgical measurement system
WO2011008606A1 (en) 2009-07-14 2011-01-20 Wavetec Vision Systems, Inc. Determination of the effective lens position of an intraocular lens using aphakic refractive power
WO2011025846A1 (en) * 2009-08-27 2011-03-03 Novartis Ag Optimizing optical aberrations in ophthalmic lenses
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EP2512372A1 (en) 2009-12-18 2012-10-24 Abbott Medical Optics Inc. Ophthalmic lens, systems and methods with angular varying phase delay
US8894204B2 (en) 2010-12-17 2014-11-25 Abbott Medical Optics Inc. Ophthalmic lens, systems and methods having at least one rotationally asymmetric diffractive structure
US9931200B2 (en) 2010-12-17 2018-04-03 Amo Groningen B.V. Ophthalmic devices, systems, and methods for optimizing peripheral vision
US8862447B2 (en) 2010-04-30 2014-10-14 Amo Groningen B.V. Apparatus, system and method for predictive modeling to design, evaluate and optimize ophthalmic lenses
ES2374916B1 (en) 2010-06-02 2013-01-30 Consejo Superior De Investigaciones Científicas (Csic) Method for producing an isoplanatic aspheric monofocal intraocular lens and lens obtained using this procedure.
US20130072591A1 (en) * 2011-09-16 2013-03-21 Christian A. Sandstedt Using the light adjustable lens (lal) to increase the depth of focus by inducing targeted amounts of asphericity
US9072462B2 (en) 2012-09-27 2015-07-07 Wavetec Vision Systems, Inc. Geometric optical power measurement device
WO2014143585A1 (en) 2013-03-11 2014-09-18 Abbott Medical Optics Inc. Intraocular lens that matches an image surface to a retinal shape, and method of designing same
EP3116441A2 (en) 2014-03-10 2017-01-18 Amo Groningen B.V. Piggyback intraocular lens that improves overall vision where there is a local loss of retinal function
CA2946356A1 (en) 2014-04-21 2015-11-26 Amo Groningen B.V. Ophthalmic devices, system and methods that improve peripheral vision
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WO2017211299A1 (en) * 2016-06-07 2017-12-14 Huey-Chuan Cheng Ophthalmic lenses and methods of manufacturing the same
CN106388974A (en) * 2016-12-09 2017-02-15 天津世纪康泰生物医学工程有限公司 Aspherical artificial lens capable of completely correcting mesopic vision

Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4195919A (en) * 1977-10-31 1980-04-01 Shelton William A Contact lens with reduced spherical aberration for aphakic eyes
US4504982A (en) * 1982-08-05 1985-03-19 Optical Radiation Corporation Aspheric intraocular lens
US5092880A (en) * 1988-10-21 1992-03-03 Genjiro Ohmi Method of determining the astigmatic power and the power for an intraocular lens, for a toric intraocular lens
US5171319A (en) * 1992-02-10 1992-12-15 Keates Richard H Foldable intraocular lens system
US5217489A (en) * 1991-04-05 1993-06-08 Alcon Surgical, Inc. Bifocal intraocular lens
US5410375A (en) * 1990-03-15 1995-04-25 Fiala; Werner J. Multifocal birefrigent lens with adjusted birefringence
US5922921A (en) * 1997-10-27 1999-07-13 Celanese International Corporation Process for the production of n-butanol
US6096077A (en) * 1997-08-20 2000-08-01 Thinoptx, Inc. Deformable intraocular corrective lens
US20010051826A1 (en) * 2000-02-24 2001-12-13 Bogaert Theo T. M. Intraocular lenses
US6353069B1 (en) * 1998-04-15 2002-03-05 Alcon Manufacturing, Ltd. High refractive index ophthalmic device materials
US20020105617A1 (en) * 2000-05-23 2002-08-08 Sverker Norrby Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
US20020122153A1 (en) * 2000-12-22 2002-09-05 Piers Patricia Ann Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
US20030063254A1 (en) * 2001-04-11 2003-04-03 Piers Patricia Ann Ophthalmic lens
US20040156014A1 (en) * 2002-11-29 2004-08-12 Piers Patricia Ann Multifocal ophthalmic lens
US6786603B2 (en) * 2002-09-25 2004-09-07 Bausch & Lomb Incorporated Wavefront-generated custom ophthalmic surfaces
US6797003B1 (en) * 1987-08-24 2004-09-28 Pharmacia & Upjohn Company Aspheric soft lens
US20050203619A1 (en) * 2003-03-31 2005-09-15 Altmann Griffith E. Aspheric lenses and lens family
US20060030938A1 (en) * 2003-03-31 2006-02-09 Altmann Griffith E Aspheric lenses and lens family

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2635970A1 (en) * 1988-09-06 1990-03-09 Essilor Int Optics has ophthalmic lens and intraocular lens, for improving the vision of a person with macular degeneration
US5050981A (en) * 1990-07-24 1991-09-24 Johnson & Johnson Vision Products, Inc. Lens design method and resulting aspheric lens
JP3247691B2 (en) * 1990-09-17 2002-01-21 株式会社ニデック Intraocular lens
US5384606A (en) * 1992-06-22 1995-01-24 Allergan, Inc. Diffractive/refractive spectacle and intraocular lens system for age-related macular degeneration
US5684560A (en) 1995-05-04 1997-11-04 Johnson & Johnson Vision Products, Inc. Concentric ring single vision lens designs
US5922821A (en) 1996-08-09 1999-07-13 Alcon Laboratories, Inc. Ophthalmic lens polymers
US6082856A (en) * 1998-11-09 2000-07-04 Polyvue Technologies, Inc. Methods for designing and making contact lenses having aberration control and contact lenses made thereby
CA2399285C (en) * 2000-02-24 2007-10-30 Pharmacia Groningen Bv Intraocular lenses
JP4459501B2 (en) 2000-05-23 2010-04-28 エイ・エム・オー・フローニンゲン・ベー・ベー Eye lens to reduce the aberrations of the eye
US6855164B2 (en) 2001-06-11 2005-02-15 Vision Solutions Technologies, Llc Multi-focal intraocular lens, and methods for making and using same
CN100392473C (en) 2002-10-04 2008-06-04 卡尔蔡斯视觉股份有限公司 Method for production of a lens and lens produced thereby
US7036931B2 (en) 2003-01-29 2006-05-02 Novartis Ag Ophthalmic lenses
EP1866693B1 (en) * 2004-04-05 2013-05-08 AMO Groningen B.V. Ophthalmic lenses with reduced chromatic aberration
US7401922B2 (en) * 2005-04-13 2008-07-22 Synergeyes, Inc. Method and apparatus for reducing or eliminating the progression of myopia

Patent Citations (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4195919A (en) * 1977-10-31 1980-04-01 Shelton William A Contact lens with reduced spherical aberration for aphakic eyes
US4504982A (en) * 1982-08-05 1985-03-19 Optical Radiation Corporation Aspheric intraocular lens
US6797003B1 (en) * 1987-08-24 2004-09-28 Pharmacia & Upjohn Company Aspheric soft lens
US5092880A (en) * 1988-10-21 1992-03-03 Genjiro Ohmi Method of determining the astigmatic power and the power for an intraocular lens, for a toric intraocular lens
US5410375A (en) * 1990-03-15 1995-04-25 Fiala; Werner J. Multifocal birefrigent lens with adjusted birefringence
US5217489A (en) * 1991-04-05 1993-06-08 Alcon Surgical, Inc. Bifocal intraocular lens
US5171319A (en) * 1992-02-10 1992-12-15 Keates Richard H Foldable intraocular lens system
US6096077A (en) * 1997-08-20 2000-08-01 Thinoptx, Inc. Deformable intraocular corrective lens
US5922921A (en) * 1997-10-27 1999-07-13 Celanese International Corporation Process for the production of n-butanol
US6353069B1 (en) * 1998-04-15 2002-03-05 Alcon Manufacturing, Ltd. High refractive index ophthalmic device materials
US20010051826A1 (en) * 2000-02-24 2001-12-13 Bogaert Theo T. M. Intraocular lenses
US20020105617A1 (en) * 2000-05-23 2002-08-08 Sverker Norrby Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
US20020122153A1 (en) * 2000-12-22 2002-09-05 Piers Patricia Ann Methods of obtaining ophthalmic lenses providing the eye with reduced aberrations
US20030063254A1 (en) * 2001-04-11 2003-04-03 Piers Patricia Ann Ophthalmic lens
US6786603B2 (en) * 2002-09-25 2004-09-07 Bausch & Lomb Incorporated Wavefront-generated custom ophthalmic surfaces
US20040156014A1 (en) * 2002-11-29 2004-08-12 Piers Patricia Ann Multifocal ophthalmic lens
US20050203619A1 (en) * 2003-03-31 2005-09-15 Altmann Griffith E. Aspheric lenses and lens family
US20060030938A1 (en) * 2003-03-31 2006-02-09 Altmann Griffith E Aspheric lenses and lens family

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2189134A1 (en) 2008-11-19 2010-05-26 Alcon Research, Ltd. Aspheric intraocular lens with improved control of aberrations
JP2010119853A (en) * 2008-11-19 2010-06-03 Alcon Research Ltd Aspheric intraocular lens with improved control of aberrations
US20100125331A1 (en) * 2008-11-19 2010-05-20 Simpson Michael J Aspheric intraocular lens with improved control of aberrations
US9220404B2 (en) * 2009-03-26 2015-12-29 Novartis Ag Ocular modeling methods and apparatus
US20120069298A1 (en) * 2009-03-26 2012-03-22 Eugene Ng Ocular modeling methods and apparatus
WO2011153158A1 (en) * 2010-06-01 2011-12-08 Elenza, Inc. Implantable ophthalmic device with an aspheric lens
US9146103B2 (en) * 2010-12-10 2015-09-29 Thales Apparatus and optical method of ranging and of high bit-rate communication
US9575334B2 (en) 2012-04-05 2017-02-21 Brien Holden Vision Institute Lenses, devices and methods of ocular refractive error
US9535263B2 (en) 2012-04-05 2017-01-03 Brien Holden Vision Institute Lenses, devices, methods and systems for refractive error
US9195074B2 (en) 2012-04-05 2015-11-24 Brien Holden Vision Institute Lenses, devices and methods for ocular refractive error
US9201250B2 (en) 2012-10-17 2015-12-01 Brien Holden Vision Institute Lenses, devices, methods and systems for refractive error
US9541773B2 (en) 2012-10-17 2017-01-10 Brien Holden Vision Institute Lenses, devices, methods and systems for refractive error
US9759930B2 (en) 2012-10-17 2017-09-12 Brien Holden Vision Institute Lenses, devices, systems and methods for refractive error
WO2014111769A1 (en) 2013-01-15 2014-07-24 Medicem Ophthalmic (Cy) Limited Bioanalogic intraocular lens
WO2017221068A1 (en) 2016-06-23 2017-12-28 Medicem Ophthalmic (Cy) Limited Light-adjustable hydrogel and bioanalogic intraocular lens
WO2018037356A1 (en) 2016-08-23 2018-03-01 Medicem Ophthalmic (Cy) Limited Ophthalmic lenses with aspheric optical surfaces and method for their manufacture

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