U.S. patent application number 11/078105 was filed with the patent office on 2005-07-14 for novel enhanced intraocular lens for reducing glare.
Invention is credited to Brady, Daniel G., Paul, Marlene L., Zhao, Huawei.
Application Number | 20050154456 11/078105 |
Document ID | / |
Family ID | 27492071 |
Filed Date | 2005-07-14 |
United States Patent
Application |
20050154456 |
Kind Code |
A1 |
Brady, Daniel G. ; et
al. |
July 14, 2005 |
Novel enhanced intraocular lens for reducing glare
Abstract
An intraocular lens implantable in an eye includes an optic for
placement in the capsular bag of the eye and for directing light
toward the retina of the eye. The optic has a central optical axis,
an anterior face, an opposing posterior face and a peripheral edge
between the faces. The peripheral edge has one or more curved or
angled surfaces that reduce glare within the IOL. For instance, a
rounded transition surface on the anterior side of the peripheral
edge diffuses the intensity of reflected light, or a particular
arrangement of straight edge surfaces refracts the light so as not
to reflect, or does not reflect at all. The intersection of the
peripheral edge and at least one of the anterior face and the
posterior face, preferably both of such faces, forms a peripheral
corner located at a discontinuity between the peripheral edge and
the intersecting face or faces. The present IOLs inhibit cell
growth from the eye in front of or in back of the optic and reduce
glare obtained in the eye in which the IOL is located.
Inventors: |
Brady, Daniel G.; (San Juan
Capistrano, CA) ; Paul, Marlene L.; (Laguna Niguel,
CA) ; Zhao, Huawei; (Irvine, CA) |
Correspondence
Address: |
ADVANCED MEDICAL OPTICS, INC.
1700 E. ST. ANDREW PLACE
SANTA ANA
CA
92705
US
|
Family ID: |
27492071 |
Appl. No.: |
11/078105 |
Filed: |
March 9, 2005 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11078105 |
Mar 9, 2005 |
|
|
|
10335578 |
Dec 31, 2002 |
|
|
|
6884262 |
|
|
|
|
10335578 |
Dec 31, 2002 |
|
|
|
10245920 |
Sep 18, 2002 |
|
|
|
10245920 |
Sep 18, 2002 |
|
|
|
09507602 |
Feb 18, 2000 |
|
|
|
6468306 |
|
|
|
|
09507602 |
Feb 18, 2000 |
|
|
|
09448713 |
Nov 24, 1999 |
|
|
|
09448713 |
Nov 24, 1999 |
|
|
|
09086882 |
May 29, 1998 |
|
|
|
6162249 |
|
|
|
|
Current U.S.
Class: |
623/6.17 ;
623/6.16 |
Current CPC
Class: |
A61F 2002/009 20130101;
A61F 2/1613 20130101; G02B 27/0018 20130101; A61F 2002/1699
20150401 |
Class at
Publication: |
623/006.17 ;
623/006.16 |
International
Class: |
A61F 002/16 |
Claims
1.-10. (canceled)
11. An intraocular lens that reduces glare from incoming light rays
to the retina of an eye, comprising: fixation members adapted to
fix the intraocular lens in the capsular bag of the eye; and an
optic having an anterior face and an opposed posterior face, the
optic being coupled to the fixation members and including: a
light-transmitting portion centered on a central optical axis and
shaped to focus light on the retina of the eye; anterior and
posterior peripheral regions on the anterior and posterior faces of
the optic, respectively, and circumscribing the light-transmitting
portion; and a peripheral edge between the anterior and posterior
faces; wherein the anterior peripheral region and the peripheral
edge have roughened surfaces so as to be partially opaque to the
transmission of light, and wherein the roughened surfaces have an
irregular pattern.
12. The intraocular lens of claim 11, wherein the periphery of the
optic is made of a light absorbing material.
13. The intraocular lens of claim 11, wherein the optic further
includes a peripheral corner located at a discontinuity between the
peripheral edge and the posterior face for inhibiting cell growth
onto the optic.
14. The intraocular lens of claim 11, wherein the peripheral edge
includes an anterior convex portion adjacent the anterior
peripheral region.
15. The intraocular lens of claim 14, wherein the peripheral edge
further includes two surfaces with linear cross-sectional
configurations, one of which describes a cylindrical surface around
the central optical axis and the other describes a partial conical
surface around the central optical axis.
16. The intraocular lens of claim 15, wherein, from the anterior
face to the posterior face, the peripheral edge comprises, in
sequence, the anterior convex portion, the partial conical surface,
and the cylindrical surface.
17. (canceled)
18. The intraocular lens of claim 17, wherein the roughness of the
anterior peripheral region and the peripheral edge is sufficient so
as to be visible at a magnification of 10.times..
19. The intraocular lens of claim 18, wherein the roughness of the
anterior peripheral region and the peripheral edge has a scattering
level of about 80%.
20-26. (canceled)
27. The intraocular lens of claim 11, wherein the roughness of the
partially opaque region or edge is sufficient so as to be visible
to the naked eye.
28. (canceled)
29. The intraocular lens of claim 12, wherein the light absorbing
material is a colored base material.
30. The intraocular lens of claim 11 further including at least one
of a posterior edge corner and an anterior edge corner, and wherein
the peripheral edge is linear.
31. The intraocular lens of claim 11, wherein the fixation members
and the optic are constructed from one unitary piece of
material.
32. The intraocular lens of claim 14, wherein only the anterior
convex portion of the peripheral edge is roughened so as to be
partially opaque to the transmission of light.
33. The intraocular lens of claim 32, wherein the roughness of the
anterior convex portion of the peripheral edge has a scattering
level of about 80%.
34. An intraocular lens that reduces glare from incoming light rays
to the retina of an eye, which comprises: fixation members adapted
to fixate the intraocular lens within the capsular bag of the eye;
and an optic having an anterior face and an opposed posterior face,
the optic being coupled to the fixation members and further
comprising: a light transmitting portion centered on a central
optical axis and shaped to direct light on the retina of the eye;
an anterior peripheral region and a posterior peripheral region on
the anterior and posterior faces of the optic, respectively, and
circumscribing the light-transmitting portion; and a peripheral
edge between the anterior and posterior faces; wherein only
selected aspects of the anterior peripheral region and the
peripheral edge are partially opaque to the transmission of
light.
35. The intraocular lens of claim 34, wherein each of the
peripheral edge, which includes a roughened anterior convex portion
adjacent the anterior peripheral portion, and the balance of the
peripheral edge are roughened so as to be partially opaque to the
transmission of light, and the rest of the intraocular lens is not
so roughened.
36. The intraocular lens of claim 35, wherein the roughness of each
of said selected portions of the peripheral edge has a scattering
level of at least about 80%.
37. The intraocular lens of claim 35, wherein the roughness of each
of said selected portions has a scattering level of less than
80%.
38. The intraocular lens of claim 35, wherein the fixation members
and the optic are constructed from one unitary piece of
material.
39. The intraocular lens of claim 34, further including at least
one of a posterior edge corner and an anterior edge corner, wherein
the peripheral edge is linear.
Description
RELATED APPLICATION
[0001] The present application is a continuation-in-part of
co-pending application Ser. No. 10/245,920 filed Sep. 17, 2002,
which is a continuation of U.S. Ser. No. 09/507,602, filed Feb. 18,
2000, which is a continuation of application Ser. No. 09/448,713,
filed Nov. 24, 1999, now abandoned, which is a continuation-in-part
of application Ser. No. 09/086,882, filed May 29, 1998, now U.S.
Pat. No. 6,162,249, issued Dec. 19, 2000. The disclosure of each of
these applications and the patent is incorporated in its entirety
by reference herein.
BACKGROUND OF THE INVENTION
[0002] This invention relates to intraocular lenses (IOLs) and,
more particularly, to IOLs which inhibit migration or growth of
cells from the eye onto the IOL and reduce glare in the eye.
[0003] An intraocular lens is commonly used to replace the natural
lens of a human eye when warranted by medical conditions. It is
common practice to implant an IOL in a region of the eye known as
the capsular bag or posterior capsule.
[0004] One potential concern with certain IOLs following
implantation is that cells from the eye, particularly epithelial
cells from the capsular bag, tend to grow in front of and/or in
back of the optic of the IOL. This tends to block the optic of the
IOL and to impair vision.
[0005] A common treatment for this condition is to use a laser to
destroy the cells and a central region of the capsular bag.
Although this treatment is effective, the laser is expensive and is
not available throughout the world. There is also cost associated
with the laser treatment as well as some patient inconvenience and
risk of complications. Finally, the laser treatment may affect the
performance of some IOLs.
[0006] Another potential concern after certain IOLs are implanted
has to do with glare caused by light reflecting off of the IOLs, in
particular, the edges of IOLs. Such glare can be an annoyance to
the patient and may even lead to removal and replacement of the
IOL.
[0007] It would be advantageous to provide IOLs which inhibit
growth of cells from the eye onto the IOLs and/or which reduce
glare caused by the IOLs in the eye.
SUMMARY OF THE INVENTION
[0008] New IOLs have been discovered. Such IOLs are effective to
inhibit cell growth, in particular epithelial cell growth, from the
eye onto the optic of the IOLs. The IOLs are structured so as to
reduce glare, in particular edge glare, in the eye resulting from
the presence of the IOL. The present IOLs are straightforward in
design and construction, are easily manufactured, can be implanted,
or inserted in the eye using conventional techniques, and are
effective and produce substantial benefits in use in the eye.
[0009] In one broad aspect of the present invention, the present
IOLs are implantable in the eye and comprise an optic having a
central optical axis, an anterior face, an opposing posterior face
and a peripheral edge or edge surface between the faces. The optic
is adapted for placement in the capsular bag of the eye and for
directing light toward the retina of the eye. In a very useful
embodiment, the IOLs further comprise at least one fixation member,
preferably two fixation members, and more preferably two elongated
fixation members, coupled to the optic for use in fixing the IOLs
in the eye.
[0010] In a preferred aspect, the present invention provides a
reduced-glare intraocular lens implantable in the eye and including
an optic adapted for placement in the capsular bag of the eye for
directing light toward the retina of the eye. The optic has a
central optical axis, an anterior face, an opposing posterior face,
and a peripheral edge. The peripheral edge has a least one surface
with a linear cross-sectional configuration that is oriented other
than parallel to the central optical axis. Further, the peripheral
edge and the anterior face, and/or the peripheral edge and the
posterior face, intersect to form at least one peripheral edge
corner located at a discontinuity between the peripheral edge and
the intersecting anterior or posterior face. The peripheral edge
may also include a rounded transition surface on its anterior side,
wherein the peripheral edge corner is provided only between the
peripheral edge and intersecting posterior face. The peripheral
edge may also include two linear surfaces angled with respect to
one another, wherein the other linear surface may be oriented
parallel to the optical axis.
[0011] In another aspect of present invention, a reduced-glare
intraocular lens implantable in an eye comprises an optic adapted
for placement in the capsular bag of the eye and for directing
light toward the retina of the eye. The optic has a central optical
axis, an anterior face, and a posterior face. An outer edge of the
optic is defined by a peripheral edge that includes, in
cross-section, a linear surface that is non-parallel with respect
to the optical axis and a posterior corner defining the posterior
limit of the peripheral edge. Advantageously, cell growth from the
eye in front of or in back of the optic is more inhibited relative
to a substantially identical intraocular lens without the posterior
corner, and reduced glare is obtained in the eye relative to a
substantially identical intraocular lens having a peripheral linear
surface that is parallel to the central optical axis. The optic may
also include a convex surface on the peripheral edge defining a
transition surface between the anterior face and the linear
surface. A second linear surface that is parallel with respect to
the optical axis may also be provided. In addition, the optic may
include first and second linear surfaces, wherein the first linear
surface is anteriorly-facing and second linear surface is parallel
with respect to the optical axis.
[0012] In still a further embodiment of the present invention, an
intraocular lens implantable in an eye includes an optic adapted
for placement in the capsular bag of the eye and for directing
light toward the retina of the eye. The optic includes a peripheral
edge extending between an anterior face and a posterior face
consisting only of a conical surface. The conical surface may be
posteriorly-facing, wherein the conical surface is sufficiently
angled with respect to the optical axis so as to increase
transmission of light from the optic through the conical surface
relative to a substantially identical intraocular lens with a
peripheral edge consisting only of a surface parallel to the
optical axis. Alternatively, a peripheral land extends between the
anterior face and conical surface, wherein the conical surface is
generally posteriorly-facing and wherein the conical surface and
the peripheral land adjacent the conical surface define an acute
included angle. In a still further form, the conical surface may be
anteriorly-facing, wherein the conical surface is sufficiently
angled with respect to the optical axis so as to decrease the
probability of light internal to the optic contacting the conical
surface relative to a substantially identical intraocular lens with
a peripheral edge consisting only of a surface parallel to the
optical axis.
[0013] Another aspect of present invention is an intraocular lens
including an optic defining a central optical axis, an anterior
face, and a posterior face. A peripheral edge extending between the
anterior face and the posterior face includes, in cross-section, a
linear edge surface terminating at its anterior side in an anterior
edge corner. An anterior land adjacent the anterior edge corner,
wherein the linear edge surface and the anterior land define an
acute included angle so as to increase transmission of light from
the optic through the conical surface relative to a substantially
identical intraocular lens with a linear edge surface and anterior
land that define an included angle of 90.degree. or more.
[0014] In a still further form, the present invention provides an
intraocular lens having optic defining optical axis, an anterior
face, and a posterior face. A peripheral edge stands between the
anterior face and posterior face and includes, in cross-section, at
least two linear edge surfaces that are not parallel to the optical
axis. The two linear edge surfaces may be angled radially inwardly
toward each other to meet an apex and together define a groove.
Further, a plurality of such grooves may be provided by adjoining
linear edge surfaces. A rounded transition surface extending
between an anteriorly-facing edge surface and the anterior face of
the optic may also be provided.
[0015] The peripheral edge of the present IOLs may have a
substantially continuous curved configuration in the direction
between the anterior and posterior faces of the optic, that is
between the faces in a cross-sectional plane including the optical
axis. Indeed, the entire peripheral edge may have a substantially
continuous curved configuration in the direction between the
anterior and posterior faces of the optic.
[0016] The peripheral edge of the present IOLs may have a curved
surface, a flat surface that is either parallel to the optical axis
or not, or a combination of flat and/or curved surfaces. For
example, if a portion of the peripheral edge has a substantially
continuous curved configuration, another portion, for example, the
remaining portion, of the peripheral edge preferably has a linear
configuration in the direction between the anterior and posterior
faces of the optic which is not parallel to the optical axis.
[0017] The present IOLs preferably provide reduced glare in the eye
relative to the glare obtained with a substantially identical IOL
having a peripheral edge parallel (flat) to the central optical
axis in the direction between the faces of the optic. One or more
of at least part of the peripheral edge, a portion of the anterior
face near the peripheral edge and a portion of the portion face
near the peripheral edge may be at least partially opaque to the
transmission of light, which opacity is effective in reducing
glare. Such opacity can be achieved in any suitable manner, for
example, by providing "frosting" or physically or chemically
roughening selected portions of the optic.
[0018] In addition, the intersection of the peripheral edge and at
least one or both of the anterior face and the posterior face forms
a peripheral corner or corner edge located at a discontinuity
between the peripheral edge and the intersecting face. Such
peripheral corner, which may be considered a sharp, abrupt or
angled peripheral corner, is effective in inhibiting migration or
growth of cells from the eye onto the IOL. Preferably, the present
IOLs, with one or two such angled peripheral corners, provide that
cell growth from the eye in front of or in back of the optic is
more inhibited relative to a substantially identical IOL without
the sharp, abrupt or angled peripheral corner or corners.
[0019] The peripheral edge and the intersecting face or faces
intersect at an angle or angles, preferably in a range of about
45.degree. to about 135.degree., more preferably in a range of
about 60.degree. about 120.degree.. In one embodiment, an obtuse
angle (that is greater than 90.degree. and less than 180.degree. )
of intersection is provided. Such angles of intersection are very
effective in facilitating the inhibition of cell migration or
growth onto and/or over the anterior face and/or posterior face of
the optic of the present IOL.
[0020] In one very useful embodiment, at least one, conceivably
both, of the anterior face and the posterior face has a peripheral
region extending from the peripheral edge toward the central
optical axis. The peripheral region or regions preferably are
substantially planar, and may or may not be substantially
perpendicular to the central optical axis. Preferably, only the
anterior face has a peripheral region extending from the peripheral
edge toward the central optical axis which is substantially planar,
more preferably substantially perpendicular to the central optical
axis. The peripheral region preferably has a radial dimension of at
least about 0.1 mm, and more preferably no greater than about 2
mm.
[0021] The dimension of the optic parallel to the central optical
axis between the anterior face and the posterior face preferably is
smaller at or near the peripheral edge, for example, at the
peripheral region or regions, than at the central optical axis.
[0022] In one embodiment, at least a part or a portion of the
peripheral edge surface of the optic is generally convex relative
to the central optical axis. Alternately, at least a part or a
portion of the peripheral edge surface of the optic is generally
concave relative to the central optical axis. In a particularly
useful embodiment, a first portion of the peripheral edge surface
is generally convex relative to the central optical axis and a
second portion of the peripheral edge surface is generally concave
relative to the optical axis.
[0023] Preferably, the peripheral edge and/or the peripheral region
or regions circumscribe the central optical axis. The anterior face
and the posterior face preferably are both generally circular in
configuration, although other configurations, such as oval, is
elliptical and the like, may be employed. At least one of the
anterior and posterior faces has an additional region, located
radially inwardly of the peripheral region, which is other than
substantially planar.
[0024] Each and every combination of two or more features described
herein is included within the scope of the present invention
provided that such features are not mutually inconsistent.
[0025] The invention, together with additional features and
advantages thereof, may best be understood by reference to the
following description taken in connection with the accompanying
illustrative drawings in which like parts bear like reference
numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a plan view of one form of intraocular lens (IOL)
constructed in accordance with the teachings of present
invention.
[0027] FIG. 2 is a cross-sectional view of an optic of a prior art
IOL.
[0028] FIG. 3 is an elevational view of an optic of an exemplary
embodiment of an IOL of the present invention having a medium
diopter value.
[0029] FIG. 4 is an elevational view of an optic of a further
exemplary IOL of the present invention having a small diopter
value.
[0030] FIG. 5 is an elevational view of an optic of a further
exemplary IOL of the present invention having a large diopter
value.
[0031] FIG. 6 is an elevational view of a peripheral edge region of
the IOL of FIG. 3 showing the paths of a plurality of light rays
passing therethrough.
[0032] FIG. 7 is a cross-sectional view of a peripheral edge region
of an IOL of the present invention having an edge surface that is
parallel to the optical axis, an anteriorly-facing edge surface
that is not parallel to the optical axis and an anterior peripheral
land that is perpendicular to the optical axis.
[0033] FIG. 8 is a cross-sectional view of a peripheral edge region
of an IOL of the present invention having an anteriorly-facing edge
surface not parallel to the optical axis and an anterior peripheral
land perpendicular to the optical axis.
[0034] FIG. 9 is a cross-sectional view of a peripheral edge region
of an IOL of the present invention having an anteriorly-facing edge
surface that is not parallel to the optical axis and no peripheral
land.
[0035] FIG. 10 is a cross-sectional view of a peripheral edge
region of an IOL of the present invention having an edge surface
that is parallel to the optical axis and an anterior peripheral
land that is not perpendicular to the optical axis.
[0036] FIG. 11 is a cross-sectional view of a peripheral edge
region of an IOL of the present invention having an edge surface
that is parallel to the optical axis, an anterior peripheral land
that is perpendicular to the optical axis, and an anterior
peripheral land that is not perpendicular to the optical axis.
[0037] FIG. 12 is a cross-sectional view of a peripheral edge
region of an IOL of the present invention having a
posteriorly-facing edge surface that is not parallel to the optical
axis and no peripheral land.
[0038] FIG. 13 is a cross-sectional view of a peripheral edge
region of an IOL of the present invention having a
posteriorly-facing edge surface that is not parallel to the optical
axis and an anterior peripheral land that is perpendicular to the
optical axis.
[0039] FIG. 14a is a radial sectional view of an IOL of the present
invention showing a fixation member extending from a peripheral
edge.
[0040] FIG. 14b is an elevational view of a peripheral edge region
of the IOL of FIG. 14a.
[0041] FIGS. 15-17 are elevational views of peripheral edge regions
of IOLs of the present invention each having an anteriorly-facing
edge surface that is not parallel to the optical axis, a rounded
transition surface between the edge surface and the anterior face
of the IOL, and a posterior peripheral land.
[0042] FIG. 18 is an elevational view of a peripheral edge region
of an IOL of the present invention having a baffle structure
disposed along an anteriorly-facing edge surface.
[0043] FIG. 19 is an elevational view of a peripheral edge region
of an IOL of the present invention having an anteriorly-facing edge
surface and a rounded transition surface between the edge surface
and the anterior face of the IOL.
[0044] FIG. 20 is an elevational view of a peripheral edge region
of an IOL of the present invention having both anteriorly- and
posteriorly-facing edge surfaces.
[0045] FIG. 21 is a cross-sectional view of the optic of an
alternative IOL of the present invention.
[0046] FIG. 22 is a cross-sectional view of the optic of an
alternate embodiment of an IOL in accordance with the present
invention.
[0047] FIG. 23 is a partial cross-sectional view of the optic of a
further embodiment of an IOL in accordance with the present
invention.
[0048] FIG. 24 is a partial cross-sectional view of an additional
embodiment of an IOL in accordance with the present invention.
[0049] FIG. 25 is a partial cross-sectional view of the optic of
another embodiment of an IOL in accordance with the present
invention.
[0050] FIG. 26 is a partial cross-sectional view of the optic of a
further alternate embodiment of an IOL in accordance with the
present invention.
[0051] FIG. 27 is a partial cross-sectional view of the optic of a
still further embodiment of an IOL in accordance with the present
invention.
[0052] FIG. 28 is a partial cross-sectional view of the optic of
still another embodiment of an IOL in accordance with the present
invention.
[0053] FIG. 29a is a modeled ray tracing of the glare resulting
from light passing through a first exemplary interocular lens of
the present invention having peripheral rough surfaces over the
entire optic portion except for the central optically refractive
anterior and posterior surfaces.
[0054] FIG. 29b is a modeled ray tracing of the glare resulting
from light passing through a second exemplary interocular lens of
the present invention similar to that modeled in FIG. 29a.
[0055] FIG. 30 is a modeled ray tracing of the glare resulting from
light passing through an interocular lens similar in shape to the
lenses modeled in FIGS. 29a and 29b, but without the extensive
peripheral roughening.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0056] FIG. 1 shows an IOL 20 which generally comprises an optic 22
and fixation members 24a and 24b. In this embodiment, the optic 22
may be considered as effective for focusing light on or near the
retina of the eye. Optical axis 26 passes through the center of
optic 22 in a direction generally transverse to the plane of the
optic.
[0057] In this embodiment, the optic 22 is circular in plan and
bi-convex approaching the optical axis 26. However, this
configuration is merely illustrative as other configurations and
shapes may be employed. The optic 22 may be constructed of any of
the commonly employed materials used for rigid optics, such as
polymethylmethacrylate (PMMA), or commonly employed materials used
for resiliently deformable optics, such as silicone polymeric
materials, acrylic polymeric materials, hydrogel-forming polymeric
materials, mixtures thereof and the like.
[0058] The fixation members 24a and 24b in this embodiment are
generally C-shaped and are integral with the optic 22. However,
this is purely illustrative of the fixation members 24a and 24b as
the fixation members may be of other configurations and/or may be
separate members affixed to the optic 22 in any of a variety of
conventional ways. Stated another way, the IOLs of the present
invention may consist of one piece, with unitary optic and fixation
members, or may be three or more pieces, with two or more fixation
members connected to the optic. IOL 20 can be produced using
conventional techniques well-known in the art.
[0059] Unless expressly described hereinafter, the general
structural characteristics of IOL 20 apply to the other IOLs noted
herein.
[0060] FIG. 2 illustrates an optic 30 of an IOL of the prior art
having an optical axis OA, a convex anterior face AF, a convex
posterior face PF, and a peripheral edge 32. The peripheral edge 32
is typically circular and has a constant cross-section
circumscribing the optic 30. The optic 30 illustrated is of the
square-cornered variety which provides some inhibition of cell
growth onto the optic 30, a condition known as posterior capsule
opacification (PCO). The peripheral edge 32 comprises an edge
surface 34 that is parallel to the optical axis OA, and both
anterior and posterior edge corners 36a, 36b, respectively. In
addition, anterior and posterior lands 38a, 38b, extend between the
anterior face AF and posterior face PF and respective edge corner
36a or 36b. Both the anterior and posterior lands 38a, 38b extend
substantially perpendicularly with respect to the optical axis OA.
Because of the parallel edge surface 34, the prior art optic 30
does not provide reduced edge glare as do the IOLs in accordance
with the present invention.
[0061] In the present application, the terms anterior and posterior
are used in their conventional sense; anterior refers to the front
side of the eye, while posterior refers to the rear side. A number
of surfaces of the intraocular lens of present invention are
denoted either "anteriorly-facing" or "posteriorly-facing" to
indicate their orientation with respect to the optical axis of the
lens. For purpose of explanation, a surface that is parallel to the
optical axis is neither anteriorly-facing or posteriorly-facing. A
surface that is even slightly angled in one direction or the other
can be identified with either the anterior or posterior side of the
lens, depending on which side that surface faces.
[0062] FIG. 3 illustrates an optic 40 of an IOL of the present
invention having an advantageous peripheral edge 42. The optic 40
defines an optical axis OA, a convex anterior face AF, and a convex
posterior face PF. The peripheral edge 42 is desirably circular in
shape, and has a constant cross-section circumscribing the optic
40. However, it should be understood by those skilled in the art
that the peripheral edge 42 may not extend completely around the
optic 40, and may be interrupted by alternative peripheral edge
configurations, including combinations of peripheral edge
configurations in accordance with the present invention.
[0063] The optic 40 is shown in elevational view to better
illustrate the peripheral edge 42 in relation to the convex
anterior face AF and posterior face PF. On the anterior side, the
peripheral edge 42 includes a curved or rounded transition surface
44 leading to an anterior peripheral land or region 46 that is
desirably linear and substantially perpendicular to the optical
axis OA. On the posterior side, a discontinuous posterior edge
corner 50 separates the peripheral edge 42 from the posterior face
PF, with no peripheral land. The edge corner 50 defines the
posterior limit of the peripheral edge 42. The peripheral edge 42
further comprises an edge surface 52 that is linear and
substantially parallel to the optical axis OA adjacent the
posterior edge corner 50, and an anteriorly-facing edge surface 54
that is linear and non-parallel to the optical axis OA adjacent the
rounded transition surface 44. A shallow corner or discontinuity 56
separates the parallel edge surface 52 from the non-parallel edge
surface 54.
[0064] In this respect, the term discontinuity refers to a
transition between two peripheral edge surfaces that is visible as
a corner or peripheral line on the optic. Of course, all corners
ultimately have a radius, but discontinuity in this regard pertains
only to a corner that is visible as a discrete line as opposed to a
more rounded region. In turn, "visible" in this regard refers to
visible as seen by the naked eye, or with the assistance of certain
low-power magnification devices, such as an ocular. Another way to
define corners in the presence sense is the intersection between
two linear surfaces, at least with respect to the magnification
shown in the drawings of the present application. Still another way
to look at the effect of a discontinuity at the corner of the
peripheral edge is that cell growth from the eye in front of or in
back of the optic is more inhibited relative to a substantially
identical intraocular lens without the discontinuity.
[0065] As used herein, the term "linear," used to refer to various
edge surfaces, is in all cases as viewed through the cross-section
of the particular edge. That is, the lenses of the present
invention are generally circular, and the peripheral edges thus
defined circular surfaces of revolution. A linear cross-sectional
edge can therefore defined a cylinder, or a conical surface. If the
edge is parallel to the optical axis, the surface is cylindrical.
On the other hand, if the surface is non-parallel with respect to
the optical axis, the surface is conical. Therefore, a linear,
non-parallel edge surface is conical, at least for a portion of the
peripheral edge. It should be noted that, as mentioned above, the
edge geometry around the periphery of any particular lens of the
present invention may not be constant, and the edge surfaces
disclosed herein should not be construed as necessarily extending
in a constant configuration around the entire periphery of the
lens.
[0066] Although the anterior peripheral land or region 46 is shown
as being linear and substantially perpendicular to the optical axis
OA, other configurations are contemplated. For example, the
peripheral land 46 could be other than linear, i.e., convex or
concave with respect to a plane through the medial plane of the
optic. Or, the peripheral land 46 could be angled toward or away
from the anterior side. Further, there may be more than one surface
defining the peripheral land 46, such as a curved and a linear
surface.
[0067] FIGS. 4 and 5 illustrate two further optics 60a and 60b that
have substantially the same configuration as the optic 40 of FIG.
3. That is, both optics 60a and 60b have an optical axis OA, a
convex anterior face AF, a convex posterior face PF, and a
peripheral edge 62a, 62b, respectively. Each peripheral edge 62a,
62b, comprises, respectively, a rounded transition surface 64a,
64b, and anterior peripheral land 66a, 66b that is substantially
perpendicular to the optical axis OA, a posterior edge corner 70a,
70b, an edge surface 72a, 72b that is substantially parallel to the
optical axis OA, and an anteriorly-facing edge surface 74a, 74b
that is non-parallel to the optical axis OA.
[0068] FIGS. 3, 4 and 5 illustrate optics of similar configuration
that have different dimensions based on their different magnitude
of optical correction, or diopter value. The optic 40 of FIG. 3 has
an intermediate correction diopter value of 20, the optic 60a of
FIG. 4 has a diopter value of 10, and the optic 60b of FIG. 5 has a
diopter value of 30. These relative diopter values are reflected in
the relative convexity of each. That is, the smallest diopter value
optic 40 shown in FIG. 4 has relatively shallow convex anterior
face AF and posterior face PF . In contrast, the larger diopter
value optic 60b in FIG. 5 has a larger convexity for both the
anterior face AF and posterior face PF.
[0069] Various dimensions for the respective peripheral edges of
the exemplary optics shown in FIGS. 3-5 are also given in FIGS. 4
and 5. That is, the thickness of each peripheral edge is given as
t, the thickness of the parallel edge surface is given as A, the
angle of the non-parallel edge surface is given as .theta., and a
radius of curvature of the transition surface is given as R.
[0070] The following tables provide exemplary values for these
dimensions for the optics 60a and 60b of FIGS. 4 and 5. These
dimensions are considered suitable for optics 60a and 60b that are
made from silicone. It should be noted that the dimensions for the
optic 40 of FIG. 3 are desirably approximately equal to those for
the optic 60b of FIG. 5. It should also be noted that the following
dimensions are believed to provide certain benefits as far as
reducing glare and PCO in IOLs, although not all the dimensions
have been selected for either of those particular purposes. For
example, some of the dimensions may be desirable to facilitate
manufacturing of the respective IOL.
[0071] Table I provides exemplary values for optics that are made
from acrylic.
1TABLE I EXEMPLARY DIMENSIONS FOR SILICONE IOLs T.sub.1 (in)
t.sub.2 (in) A.sub.1 (in) A.sub.2 (in) .theta..sub.1 .theta..sub.2
R.sub.1 (in) R.sub.2 (in) .023-.027 .012-.014 .002-.007 .002-.007
13-17.degree. 13-17.degree. .001-.003 .004-.006
[0072] Table II provides exemplary values for the same dimensions
as shown in FIGS. 4-5, but for optics that are made from acrylic.
In this case, the subscript "1" pertains to optics having a diopter
value of 10, while the subscript "2" pertains to optics having a
diopter value of either 20 or 30.
2TABLE II EXEMPLARY DIMENSIONS FOR ACRYLIC IOLs t.sub.1 (in)
t.sub.2 (in) A.sub.1 (in) A.sub.2 (in) .theta..sub.1 .theta..sub.2
R.sub.1 (in) R.sub.2 (in) .015-.019 .013-.017 .002-.007 .002-.007
13-17.degree. 13-17.degree. .004-.008 .004-.008
[0073] As is apparent from FIGS. 3-5, the convexity of the various
lenses along the optical axis OA increases with increasing diopter
value (the posterior face and especially the anterior face are more
highly convex). However, some surgeons prefer the intraocular
lenses to have approximately the same volume or center thickness at
the optical axis regardless of diopter power. This permits the
surgeon to use the same surgical technique across the diopter
range. Therefore, the present invention contemplates varying the
overall diameter of the optic for different diopter values. That
is, the center thickness of the intraocular lenses for different
diopter values remains the same regardless of diameter. Therefore,
the diameter of lenses having greater convexity should be reduced
to reduce the center thickness, and the diameter of flatter lenses
should be increased, both to an intermediate value. For example,
the diameter of the lower diopter value optic 60a shown in FIG. 4
may be increased so that the center thickness is closer to the
intermediate diopter value optic 40 shown in FIG. 3. Likewise, the
diameter of the higher diopter value optic 60b shown in FIG. 5 may
be decreased so that the center thickness is closer to the optic 40
shown in FIG. 3.
[0074] Therefore, the present invention contemplates a set of
intraocular lenses having varying diopter values wherein the
diameter of the optics varies generally inversely (although not
necessarily linearly) with respect to the diopter value. In this
way, a set of intraocular lenses having approximately the same
center thickness can be provided to the surgeon to help make the
implantation procedure more consistent and predictable. One example
of a set of intraocular lenses may include the optics shown in
FIGS. 3-5. The lower diopter lens 60a of FIG. 4 may have a diameter
of approximately 6.25 mm, the intermediate diopter lens 40 of FIG.
3 may have a diameter of 6.0 mm, and the higher diopter lens 60b of
FIG. 5 may have a diameter of 5.75 mm. Advantageously, an increased
diameter for lower diopter lenses corresponds to human physiology.
That is, people who require lower diopter lenses typically have
larger eyes, while people requiring high diopters tend to have
smaller eyes.
[0075] FIG. 6 illustrates a section of the peripheral edge 42 of
the optic 40 of FIG. 3 with a plurality of discrete light rays 80a,
80b, 80c, entering the peripheral edge from the anterior side. The
refracted/reflected path of each light ray through the peripheral
edge 42 is indicated, with the path of each light ray as it exits
the peripheral edge 42 indicated as 82a, 82b and 82c.
[0076] FIG. 6 thus illustrates the advantageous characteristic of
the peripheral edge 42 in diffusing incoming parallel light rays so
that the reflected light intensity is reduced. That is, any light
that ordinarily would reflect back towards the optical axis at near
its original intensity is instead diffused to reduce glare in the
IOL. The present invention contemplates utilizing a curved or
rounded transition surface, such as the surface 44, in combination
with one or more planar edge surfaces that are not parallel to the
optical axis, such as the edge surface 54. In the illustrated
embodiment, the peripheral edge 42 further includes the edge
surface 52 that is substantially parallel to the optical axis. It
is believed that the combination of the rounded transition surface
44 on the anterior side leading to the anteriorly-facing edge
surface 54 substantially reduces glare within the optic 40.
[0077] FIGS. 7-9 each illustrates one half of an optic of an IOL in
section having a configuration that reduces glare. In one design,
incoming light is refracted so as to decrease the probability of
light reflecting off the peripheral edge surfaces toward the
optical axis relative to conventional lenses. In another design,
incoming light reflects off of an internal peripheral edge surface
at a shallow angle of incidence not toward the optical axis so as
to decrease the probability of light reflecting off of other edge
surfaces relative to conventional lenses. All of the optics
disclosed in FIGS. 7-9 comprise an optical axis OA, a convex
anterior face AF, and a convex posterior face PF.
[0078] An optic 90 seen in FIG. 7 includes a peripheral edge 92
having a first edge surface 94 that is linear and substantially
parallel to the optical axis OA, and an anteriorly-facing second
edge surface 96 that is linear and non-parallel to the optical
axis. With respect to the partial cross-section of the optic 90
seen in FIG. 7, the anteriorly-facing second edge surface 96 is
angled in the counter-clockwise (ccw) direction with respect to the
optical axis OA. The edge surfaces 94 and 96 meet in the
mid-portion of the peripheral edge 92 at a discontinuity 98. A
posterior edge corner 100 separates the peripheral edge 92 from
posterior face PF, while an anterior edge corner 102 separates the
peripheral edge from a peripheral land 104 that is substantially
perpendicular to the optical axis.
[0079] An incoming light ray 106 is illustrated passing through the
peripheral land 104 to reflect off the second edge surface 96
within the optic 90. The resulting reflected ray 108 is deflected
through the optic 90 so that it misses the first edge surface 94.
In this manner, a substantial portion of the light entering the
optic 90 in the region of the peripheral edge 92 is reflected at a
relatively shallow angle of incidence off of the second edge
surface 96, and is not reflected off the first edge surface 94
toward the optical axis OA. Thus, glare is reduced. To achieve this
result, the anteriorly-facing second edge surface 96 is desirably
angled at least about 10.degree. with respect to the optical axis
OA.
[0080] FIG. 8 illustrates an optic 110 having a peripheral edge 112
comprising a single anteriorly-facing edge surface 114 that is
linear and non-parallel with respect to the optical axis OA. Thus,
the optic 110 has a single conical anteriorly-facing edge surface
114. A posterior edge corner 116 separates the edge surface 114
from the posterior face PF, and an anterior edge corner 118
separates the edge surface 114 from a peripheral land 120 that is
substantially perpendicular to the optical axis OA. An incoming
light ray 122 is illustrated striking the peripheral land 120 and
passing through the optic 110. Because of the anteriorly-facing
angle of the edge surface 114, the light ray may refract slightly
on passage through the optic 110, as indicated at 124, but will not
reflect off the surface edge 114. That is, the posterior edge
corner 116 is located farther radially outward from the optical
axis OA than the anterior edge corner 118 and a substantial portion
of light passing into the region of the peripheral edge 112 simply
passes through the material of the optic 110. To achieve this
result, the anteriorly-facing edge surface 114 is desirably angled
at least about 5.degree. with respect to the optical axis OA.
[0081] FIG. 9 illustrates an optic 130 that is substantially
similar to the optic 110 of FIG. 8, with a peripheral edge 132
defined by a single anteriorly-facing edge surface 134 that is
linear and non-parallel with respect to the optical axis OA. Thus,
the optic 130 has a single conical anteriorly-facing edge surface
134. Again, a posterior edge corner 136 separates the peripheral
edge 132 from the posterior face PF. An anterior edge corner 138
separates the peripheral edge 132 from the anterior face AF, and
there is no anterior peripheral land. The path of a light ray 140
passing through the region of the peripheral edge 132 illustrates
the elimination of any reflection off a peripheral edge surface.
That is, a substantial portion of light striking the optic 130 from
the anterior side simply passes through the optic without
reflecting toward the optical axis OA. To achieve this result, the
anteriorly-facing edge surface 134 is desirably angled at least
about 5.degree. with respect to the optical axis OA.
[0082] FIGS. 10-13 illustrate a number of optics of the present
invention that are configured to transmit internal light radially
outward from their peripheral edges as opposed to reflecting it
toward the optical axis. This can be done in a number of ways, all
of which result in light hitting the peripheral edge from the
interior of the optic at an angle that is less than the critical
angle for the refractive index of the lens material. Again, each of
the optics in FIGS. 10-13 includes an optical axis OA, a convex
anterior face AF, and a convex posterior face PF.
[0083] FIGS. 10 and 11 illustrate two substantially similar optics
150a, 150b that will be given corresponding element numbers. Each
of the optics 150a, 150b has a peripheral edge 152b, 152b defined
by an edge surface 154a, 154b that is linear and substantially
parallel to the optical axis OA. A posterior edge corner 156a, 156b
separates the edge surface 154a, 154b from the respective posterior
face PF. Both optics 150a, 150b include an acute anterior edge
corner 158a, 158b separating the edge surface 154a, 154b from an
anterior peripheral land 160a , 160b. The peripheral lands 160a,
160b are shown as linear and non-perpendicular with respect to the
optical axis OA, but it should be understood that non-linear lands
may perform equally as well, and may further diffuse the incoming
light. The peripheral land 160a of the optic 150a of FIG. 10 joins
with its anterior face AF at a discontinuity 162. On the other
hand, a peripheral land 164 that is linear and substantially
perpendicular to the optical axis OA joins the peripheral land 160b
of the optic 150b of FIG. 11 to its anterior face AF; that is,
there are two peripheral lands 160b and 164 on the optic 150b of
FIG. 11.
[0084] Incoming light rays 166a, 166b are illustrated in FIGS. 10
and 11 striking the respective peripheral lands 160a, 160b and
passing through the material of the respective optics 150a, 150b
toward the edge surfaces 154a, 154b. Because of the particular
angle of the peripheral lands 160a, 160b, the light rays strike the
edge surfaces 154a, 154b at angles that are less than the critical
angle for the refractive index of the lens material. Therefore,
instead of reflecting off of the edge surfaces 154a, 154b, the
light rays pass through the peripheral edges 152a, 152b as
indicated by the exit rays 168a, 168b. The included angles between
the edge surfaces 154a, 154b and the peripheral lands 160a, 160b
are shown .alpha..sub.1 and .alpha..sub.2. These angles are
preferably less than 90.degree., more preferably within the range
of about 45.degree. to 88.degree., and most preferably within the
range of about 70.degree. to 88.degree.. Of course, these ranges
may differ depending on the refractive index of the material.
[0085] FIGS. 12 and 13 illustrate similar optics 170a, 170b that
each have a peripheral edge 172a, 172b defined by a
posteriorly-facing edge surface 174a, 174b that is linear and
non-parallel with respect to the optical axis OA. A posterior edge
corner 176a, 176b separates the edge surface 174a, 174b from the
posterior face PF. On the optic 170a of FIG. 12, an anterior edge
corer 178a separates the edge surface 174a from the anterior face
AF, without a peripheral land. In contrast, as seen in FIGS. 13 an
anterior edge corner 178b separates the edge surface 174b from a
peripheral land 180 that is linear and substantially perpendicular
to the optical axis OA of the optic 170b. The peripheral land 180
meets the anterior face AF at a discontinuity 182.
[0086] The angles of the anterior edge corners 178a and 178b are
indicated at .beta..sub.1 and .beta..sub.2. The magnitude of the
angle .beta..sub.1 depends both on the convexity of the anterior
face AF and the angle of the posteriorly-facing edge surface 174a
with respect to the optical axis OA. The anterior face AF may have
widely differing convexities, but desirably the posteriorly-facing
edge surface 174a is at least 2.degree. (clockwise in the drawing)
with respect to the optical axis OA. Therefore, the angle
.beta..sub.1 is preferably less than about 120.degree., and more
preferably are within the range of about 70.degree. to 120.degree..
The magnitude of the angle .beta..sub.2 seen in FIG. 13 depends
both on the angle of the peripheral land 180 and the angle of the
posteriorly-facing edge surface 174b with respect to the optical
axis OA. The peripheral land 180 is shown as linear and
perpendicular with respect to the optical axis OA, but it should be
understood that non-linear and non-parallel lands may perform
equally as well. Desirably the posteriorly-facing edge surface 174b
is at least 2.degree. (clockwise in the drawing) with respect to
the optical axis OA. Therefore, the angle .beta..sub.2 is
preferably acute, and more preferably is within the range of about
30.degree. to 88.degree.. Of course, these ranges may differ
depending on the refractive index of the material.
[0087] FIGS. 12 and 13 illustrate incoming light rays 184a, 184b
that strike the anterior side of the respective optic 170a, 170b
adjacent the peripheral edges 172a, 172b and subsequently pass
through the material of the optic and through the edge surfaces
174a, 174b without reflection. Again, this phenomenon is caused by
the angles at which the light rays strike the edge surfaces 174a,
174b, which are lower than the critical angle for the refractive
index of the lens material. As a result, the light rays simply pass
through the peripheral edges 172a, 172b without reflecting back
towards the optical axis OA.
[0088] FIG. 14a illustrates a further embodiment of an IOL 200 of
the present invention having an optic 202 and a plurality of
fixation members 204 extending radially outward therefrom, only one
of which is shown. FIG. 14b is an enlargement of a peripheral edge
region of the optic 202. As always, the optic 202 includes an
optical axis OA, a convex anterior face AF, and a convex posterior
face PF.
[0089] With reference to FIG. 14b, the optic 202 includes a
peripheral edge 206 defined by an anteriorly-facing edge surface
208 that is linear and non-parallel with respect to the optical
axis OA. A curved or rounded transition surface 210 smoothly blends
the linear edge surface 208 to the convex anterior face AF. An
acute posterior edge corner 212 separates the edge surface 208 from
a peripheral land 214 that is linear and substantially
perpendicular to the optical axis OA. The peripheral land 214 joins
with the convex posterior face PF at a discontinuity 216. FIG. 14a
illustrates a plane 218 coincident with the circular posterior edge
corner 212. This plane represents a separation line between two
mold halves used to form the optic 202. In this manner, the acute
peripheral edge corner 212 can be easily formed between the mold
halves.
[0090] The embodiment shown in FIGS. 14a and 14b incorporates a
combination of several advantageous features previously described.
That is, the rounded transition surface 210 tends to diffuse light
rays entering from the anterior side, as described above with
respect to the embodiment of FIGS. 3-5. In addition, the edge
surface 208 is angled in such a manner that some of the light
passing through the transition surface 210 will not even strike it,
and the light that does will be reflected at a relatively shallow
angle of incidence that reduces glare.
[0091] FIGS. 15-17 illustrate the peripheral edges of three optics
220a, 220b, 220c having similar shapes. The optic 220a of FIG. 15
has a peripheral edge defined by an anteriorly-facing surface 222a
that is linear and non-parallel with respect to the optical axis,
an acute posterior edge corner 224a, and a rounded anterior
transition surface 226a blending with the anterior face AF. A
peripheral land 228a that is generally perpendicular with respect
to the optical axis extends between the posterior face PF and the
edge corner 224a, and joins with the posterior face PF at a
discontinuity 230a. The included angle between the surface 222a and
the peripheral land 228a is relatively small, and the rounded
transition surface 226a protrudes slightly outward from the surface
222a.
[0092] The peripheral edge of the optic 220b shown in FIG. 16 also
includes an anteriorly-facing surface 222b that is linear and
non-parallel with respect to the optical axis, an acute posterior
edge corner 224b, and a rounded anterior transition surface 226b
blending with the anterior face AF. A peripheral land 228b that is
not perpendicular to the optical axis extends between the posterior
face PF and the edge corner 224b. The peripheral land 228b joins
with the posterior face PF at a discontinuity 230b. The included
angle between the surface 222b and the peripheral land 228b is
slightly larger than that shown in FIG. 15, primarily because the
surface 222b has a shallower angle with respect to the optical axis
than the surface 222a.
[0093] The peripheral edge of the optic 220c shown in FIG. 17 also
includes an anteriorly-facing surface 222c that is linear and
non-parallel with respect to the optical axis, an acute posterior
edge corner 224c, and a rounded anterior transition surface 226c
blending with the anterior face AF. A peripheral land 228c that is
not perpendicular to the optical axis extends between the posterior
face PF and the edge corner 224c. The peripheral land 228c joins
with the posterior face PF at a discontinuity 230c. The optic 220c
is fairly similar to the optic 220b, but has a slightly less convex
posterior face PF.
[0094] FIG. 18 illustrates the peripheral edge of an optic 240
having a saw-tooth or baffled edge surface 242. The edge surface
242 is generally aligned to face the anterior side of the optic 240
and includes multiple tooth facets or surfaces 244a and 244b
defining peaks 246 and troughs 248. Each tooth surface 244a is
desirably parallel to the other surfaces on the same side of each
tooth, as is each tooth surface 244b with respect to the others on
the other side of each tooth. The peripheral edge of the optic 240
further includes a posterior edge corner 250 and a rounded
transition surface 252 blending into the anterior face AF. A
peripheral land 254 that is generally perpendicular to the optical
axis extends between the posterior face PF and the edge corner
250.
[0095] Still with reference to FIG. 18, light striking the
peripheral edge of the optic 240 from the anterior side is
scattered and diffused upon passage through the baffled edge
surface 242 and the rounded transition surface 252. This helps
reduce glare within the optic 240. In addition, the edge surface
242 is angled so as to be non-parallel with respect to the optical
axis, and thus some of the light rays internal to the optic 240
will not even strike this edge surface to further reduce glare.
[0096] An optic 260 that includes a linear posteriorly-facing edge
surface 262 is seen in FIG. 19. The peripheral edge of the optic
260 comprises the edge surface 262, a rounded transition surface
264 blending to the anterior face AF, and a peripheral edge corner
266 adjacent a short peripheral land 268. The advantages of the
posteriorly-facing edge surface 262 were described previously with
respect to FIGS. 12 and 13, and primarily involved light being
transmitted through the edge surface as opposed to being internally
reflected off of it. Of course, light that is transmitted through
the edge surface 262 as opposed to being reflected off of it cannot
contribute to glare. In addition, the rounded transition surface
264 helps to diffuse light rays striking the peripheral edge, thus
further reducing glare.
[0097] FIG. 20 illustrates an optic 280 having both an anterior
edge corner 282 and posterior edge corner 284. A posteriorly-facing
edge surface 286 extends from the anterior edge corner 282 to an
apex 288, and an anteriorly-facing edge surface 290 extends between
the apex and the posterior edge corner 284. The apex 288 defines
the midpoint of a groove, and the resulting configuration in
cross-section is something like a forked-tongue. A pair of
peripheral lands 292a, 292b extends between the edge corners 282,
284 and the respective anterior and posterior faces of the optic
280. The peripheral lands 292a, 292b are desirably perpendicular to
the optical axis. Again, the provision of linear edge surfaces that
are non-parallel with respect to the optical axis helps reduce
glare within the optic 280. Furthermore, the relatively sharp edge
corners 282, 284 helps reduce PCO by inhibiting cell growth on both
the anterior and posterior sides of the optic 280.
[0098] Another embodiment of the invention seen in FIG. 21 has an
optic 300 with an anterior face 302, a posterior face 304, an
anterior peripheral region 306, a posterior peripheral region 308
and a peripheral edge surface 310. The peripheral edge surface 310
has a continuously curved, concave configuration, for example, in
cross-section. The peripheral edge surface 310 intersects anterior
peripheral region 306 at anterior peripheral corner edge 312 at an
angle of about 70.degree.. Corner edge 312 is at a discontinuity
between anterior face 302 (anterior peripheral region 306) and
peripheral edge surface 310, and circumscribes optical axis 314.
Peripheral edge surface 310 intersects posterior peripheral region
308 at posterior peripheral corner edge 316 at an angle of about
70.degree. Corner edge 316 is at a discontinuity between posterior
face 304 (posterior peripheral region 308) and peripheral edge
surface 310, and circumscribes optical axis 314.
[0099] The anterior and posterior peripheral regions 306 and 308
extend radially inwardly, for example, for a distance of about 0.1
mm to about 1.0 mm or more (about 0.5 mm as shown in FIG. 21), from
the peripheral edge surface 310, and peripheral corner edge 312 and
316 respectively, and are substantially planar, more particularly,
substantially perpendicular to the optical axis 314 of optic 300.
Anterior face 302 includes an additional anterior region 318 which
is convex, not planar. Posterior face 304 includes an additional
posterior region 320 which also is convex, not planar. The
dimension of optic 300 between anterior face 302 and posterior face
304 at the peripheral regions 306 and 308 is smaller than the same
dimension at the optical axis 314.
[0100] It is found that implanting an IOL having the optic 300 in
the capsular bag of an eye effectively inhibits or retards cell
migration or growth, for example, epithelial cell migration or
growth, from the eye onto and/or over the anterior and posterior
faces 302 and 304 of optic 300. In addition, it is found that a
reduced amount of edge glare is obtained with an IOL having the
optic 300 implanted in the capsular bag of the eye.
[0101] Without wishing to limit the invention to any particular
theory of operation, it is believed that an IOL having the optic
300 provides for inhibition of cell migration or growth onto and/or
over the optic 300 because of the sharp or abrupt peripheral corner
edges 312 and 316. Thus, it is believed that the cells from the eye
have a reduced tendency to grow onto and/or over the anterior face
302 and posterior face 304 relative to a substantially identical
IOL without such peripheral corner edge. In addition, it is
believed that the reduced glare obtained using an IOL having the
optic 300 results from the curved configuration of the peripheral
edge surface 310. Thus, an IOL having the optic 300 including the
substantially continuously curved peripheral edge surface 310
provides reduced glare relative to a substantially similar IOL
having a peripheral edge surface which is substantially parallel,
for example, in cross-section, to the optical axis of the IOL.
[0102] FIG. 22 illustrates an alternate embodiment of an IOL in
accordance with the present invention. This IOL has an optic shown
generally at 330. Except as expressly described herein, optic 330
is structured and functions similarly to optic 300.
[0103] The principal difference between the optic 330 and the optic
300 relates to the shape of the anterior face 332 and the shape of
posterior face 334. Specifically, anterior face 332 is convex
throughout, and optic 330 does not include a substantially planar
anterior peripheral region. This convex anterior face 332
intersects peripheral edge surface 336 at sharp anterior peripheral
corner edge 338. Similarly, posterior face 334 is convex
throughout, and optic 330 does not include a substantially planar
posterior peripheral region. This convex posterior face 334
intersects peripheral edge surface 336 at sharp posterior
peripheral corner edge 340. The specific configuration of anterior
face 332 and posterior face 334 can be independently provided to
address the needs of any given specific application including the
following factors; the vision correction or corrections desired,
the size of optic 330, the size of the eye in which an IOL having
optic 330 is to be placed and the like factors. Optic 330 inhibits
or retards cell migration or growth and provides a reduced amount
of edge glare as does the optic 300, described above.
[0104] FIG. 23 illustrates a further embodiment of an IOL in
accordance with the present invention. This IOL has an optic shown
generally at 350. Except as expressly described herein, optic 350
is structured and functions similarly to optic 330.
[0105] The principal difference between optic 350 and optic 330
relates to the shape of peripheral edge surface 352. Specifically,
the curvature of peripheral edge surface 352 is more complex
relative to the curvature of peripheral edge surface 336. In
particular, the curvature of edge surface 352 varies substantially
continuously while the curvature of edge surface 336 is a
substantially constant concave arc (in cross-section). Peripheral
edge surface 352 is configured to reduce the amount of edge glare
obtained with optic 350 in the eye relative to, for example, IOL 30
of FIG. 2. The specific configuration or curvature of peripheral
edge surface 352 is provided to address the needs of a specific
application, including the following factors: the size of the optic
350, the size of the eye in which an IOL having the optic 330 is to
be placed and the like factors.
[0106] FIG. 24 illustrates an additional embodiment of the present
invention. The IOL illustrated in FIG. 24 has an optic shown
generally at 360. Except as expressly described herein, optic 360
is structured and functions similarly to optic 330.
[0107] The primary difference between optic 360 and optic 330
relates to the configuration of peripheral edge surface 362.
Specifically, the curvature of peripheral edge surface 362 varies
substantially continuously (in a manner which is substantially the
reverse of the curvature of peripheral edge surface 352 of optic
350) while the curvature of edge 336 is a substantially constant
concave arc (in cross-section). The peripheral edge surface 362 of
optic 360 is effective in reducing the glare caused by the presence
of optic 360 in the eye relative to the glare obtained with IOL 30
of FIG. 2 in the eye.
[0108] FIG. 25 illustrates an additional embodiment of an IOL in
accordance with the present invention. Except as expressly
described herein, this IOL, having an optic shown generally at 370
is structured and functions similarly to optic 330.
[0109] The primary difference between optic 370 and optic 330
relates to the configuration of the peripheral edge surface 372.
Specifically, peripheral edge surface 372 includes a first portion
374 which is concave relative to the optical axis 376 of optic 370.
Peripheral edge surface 372 also includes a second portion 378
which is convex relative to the optical axis 376 of optic 370.
Thus, the curvature of the peripheral edge surface of the present
IOLs, for example, peripheral edge surface 372 of optic 370, can be
relatively complex. Peripheral edge surface 372 is effective to
provide reduced glare in the eye relative to IOL 30 of FIG. 2. In
addition, it should be noted that the peripheral edge surface 372
intersects anterior face 380 at anterior peripheral corner edge 382
at an angle of about 90.degree.. Similarly, the peripheral edge
surface 372 intersects posterior peripheral region 384 at posterior
peripheral corner edge 386 at an angle of about 90.degree..
[0110] Optic 370, as with all of the IOLs in accordance with the
present invention, is effective in inhibiting or retarding cell
migration or growth from the eye onto or over the optic 370.
[0111] FIG. 26 illustrates a further alternate embodiment of an IOL
in accordance with the present invention. This IOL has an optic
shown generally at 400. Except as expressly described herein, optic
400 is structured and functions substantially similarly to optic
330.
[0112] The primary differences between optic 400 and optic 330
relate to the configuration of peripheral edge surface 402 and the
configuration of the intersection between anterior face 404 and
peripheral edge surface 402 of optic 400. Specifically, peripheral
edge surface 402 has a continuously curved configuration somewhat
similar to peripheral edge surface 372 of optic 370. Also, the
anterior face 404 intersects peripheral edge surface 402 on a curve
(that is on a continuity not at a discontinuity). In other words,
the intersection of anterior face 404 and peripheral edge surface
402 is smooth or continuous, not sharp or discontinuous.
[0113] Optic 400 is effective in reducing the amount of glare
obtained with optic 400 in the eye relative to IOL 30 of FIG. 2 in
the eye. Also, optic 370 is effective in retarding or inhibiting
migration from the eye onto and/or over cell growth or migration
from the eye onto and/or over the posterior face 406 of optic
400.
[0114] FIG. 27 illustrates a still further embodiment of an IOL in
accordance with the present invention. Except as expressly
described herein, this IOL, having an optic shown generally at 410
is structured and functions similarly to optic 330.
[0115] The primary difference between optic 410 and optic 330
relates to the configuration of the peripheral edge surface 412 and
to the configuration of posterior face 414. Specifically,
peripheral edge surface 412 is convex relative to the optical axis
416 of optic 410. Peripheral edge surface 412 does not intersect
anterior face 418 at a sharp or discontinuous corner edge, but does
intersect posterior face 414 at an obtuse angle at posterior
peripheral corner 420. Posterior face 414 includes a peripheral
region 422 which is substantially perpendicular to optical axis
416. Anterior face 418 includes a peripheral region 424 which is
roughened to be at least partially opaque to the transmission of
light. The combination of the convex peripheral edge surface 412
and the at least partially opaque peripheral region 424 is
particularly effective in reducing glare, for example, from corner
420, obtained with an IOL having optic 410 in the eye.
[0116] FIG. 28 illustrates still another embodiment of an IOL in
accordance with the present invention. This IOL has an optic shown
generally at 440. Except as expressly described herein, optic 440
is structured and functions substantially similarly to optic
330.
[0117] The primary differences between optic 440 and optic 330
relate to the configuration of peripheral edge surface 442, the
configuration of the intersection between anterior face 444 and
peripheral edge surface 442 of optic 440 and the configuration of
posterior face 446. Peripheral edge surface 442 includes a first
portion 448 which is convex relative to optic axis 450 of optic
440. Peripheral edge surface 442 also includes a second portion 452
which transitions from first portion 448 and intersects posterior
face 446 at corner 454. Peripheral edge surface 442 does not
intersect anterior face 444 at a sharp or discontinuance corner
edge. Posterior face 446 includes a peripheral region 456 which is
substantially perpendicular to optical axis 450. Anterior face 444
includes the peripheral region 458 which is roughened to be at
least partially opaque to the transmission of light. Region 460 of
peripheral edge surface 442 and region 462 of posterior face 446
are also roughened to be at least partially opaque to the
transmission of light. The combination of the peripheral edge
surface 442 and the at least partially opaque regions 458, 460, 462
is particularly effective in reducing glare, for example, from
corner edge 454, obtained with optic 440 in the eye.
[0118] In addition to designing the geometry of the peripheral edge
of the intraocular lenses of the present invention to reduce glare
and posterior capsule opacification (PCO), the edges and surfaces
near the edges may be "textured" or frosted to cause scatter of
light impinging on the peripheral region. Such scattering helps
reduce edge glare. In addition, use of texture in combination with
various edge geometries may help reduce PCO. Various texturing
regimens may be used, as described in U.S. Pat. No. 5,693,094,
entitled IOL for Reducing Secondary Opacification, hereby expressly
incorporated by reference. With respect to specific embodiments,
IOLs made of silicone desirably include texturing/frosting on at
least one edge surface as well as on a peripheral region of the
posterior face, or intermediate land. Acrylic IOLs, on the other
hand, desirably include texturing/frosting on at least one edge
surface, and preferably on an edge surface that is parallel to the
optical axis.
[0119] The intraocular lenses of the present invention may be
manufactured using a variety of techniques, including injection
molding, compression molding, lathing, and milling. Those of skill
in the art will understand how to form the mold dies, or program
the cutting tools to shape the lenses in accordance with present
invention. Importantly, care must be taken to avoid rounding the
various corners or discontinuities for the particular optic during
the polishing process. Therefore, the corners must be masked or
otherwise protected while the lens is being polished.
Alternatively, the unmasked lens may be polished and then the
various edge surfaces re-cut to insure sharp corners.
[0120] With reference back to FIG. 1, the design of the fixation
members 24a, 24b may play an important role in reducing the risk of
PCO for any particular lens. That is, the fixation members 24a, 24b
must be designed such that during capsular contraction, there is
enough axial movement and accompanying bias of the lens against the
posterior capsule to seal the capsule around the posterior edge
corners of the lens. A variety of fixation members 24a, 24b are
known in the art that can provide the required posterior bias to
the lens. The precise configuration of the fixation members 24a,
24b may vary depending on the overall lens diameter, the diameter
of the optic, the angle of the fixation member, the stiffness of
the fixation member material, the gauge of the fixation member, the
geometry of the fixation member, and the way in which the fixation
member is attached to the lens.
[0121] The present invention very effectively provides IOLs which
inhibit cell growth or migration, in particular epithelial cell
growth or migration from a capsular bag, onto and/or over the IOL
optics. In addition, the IOLs produce reduced glare, in particular
edge glare, relative to a lens having a peripheral edge which is
substantially parallel, in cross-section, to the optical axis of
the IOL optic. These benefits are achieved with IOLs which are
easily manufactured and inserted in the eye. Such IOLs can be made
of any suitable material, and provide effective performance and
substantial benefits to the patient.
[0122] Although the use of a roughened or otherwise irregular
surface on a portion of an intraocular lens has been proposed
(e.g., see U.S. Pat. No. 5,549,670 to Young, et al.), the purpose
has primarily been to provide a barrier to cell migration across
the lens. The present invention contemplates the use of specific
roughened or otherwise partially opaque surfaces around the
peripheral edge area of the intraocular lens to greatly reduce
glare from incoming light. As explained above, the peripheral edge
and the adjacent surfaces on the anterior and/or posterior face of
the optic of the interocular lens are desirably at least partially
opaque to produce the beneficial glare reduction. Preferably, all
three of these external surfaces--i.e., the peripheral edge, the
anterior peripheral region, and posterior peripheral region--are
partially opaque to the transmission of light such that internally
and inwardly reflecting rays from incoming light are substantially
eliminated. That is, light rays striking the peripheral edge or
adjacent regions are absorbed to such an extent on passage through
and between the partially opaque surfaces that they do not reflect
inward through the optic and thus do not cause unwanted visual
symptoms (e.g., so-called "pattern glare"). Most preferably, all
but the centered light-transmitting or refractive portion of the
optic is rendered partially opaque to the transmission of light so
as to maximize glare reduction. In practice, light scatters more
than once if multiple surfaces are rendered partially opaque or
roughened. Incoming light scatters ones through the anterior
surface and hits the peripheral edge and scatters again. If
roughening is provided on the posterior surface, the already
scattered light scatters again and thus the intensity of any
reflected glare is extremely low.
[0123] In addition to providing a particular external surface
characteristic, such as roughening, to increase the light-absorbing
quality of the non-refractive portion of the intraocular lens, a
material having a light absorbing color or composition may be used.
The color can be mixed into the otherwise optically transparent
lens material (e.g., silicone) and molded around the peripheral
edge area. Alternatively, the central optic portion can be insert
molded around a colored ring. If the intraocular lens is machined,
the starting blank can be formed with a ring of color and the optic
or refractive surfaces can then be machined, typically with a
lathe, in the central region. Small particles or bubbles within the
lens material may also produce the same result. The light absorbing
color or composition may be provided externally, such as just on
the peripheral edge surface, or on one of the anterior or posterior
peripheral regions, or may be provided throughout the internal
structural matrix of the peripheral edge.
[0124] In a most preferred embodiment, the partially opaque
surfaces or light absorbing internal or external structures are
utilized in combination with specific edge configurations, such as
those described above. For example, a rounded anterior corner of
the peripheral edge has been found to reduce unwanted light ray
reflection and glare. Likewise, providing two differently-angled
linear (in radial cross-section) peripheral edge surfaces in
conjunction with the rounded anterior edge corner further reduces
glare.
[0125] Tests and simulations indicate that glare reduction of
lenses produced in accordance with the present invention surpasses
that of other lens designs. FIGS. 29a, 29b and 30 illustrate
results of computer simulations or models of light passing through
a number of intraocular lenses in an environment that mimics the
eye. FIGS. 29a and 29b are models of intraocular lenses of the
present invention, while FIG. 30 is a model of an intraocular lens
of the prior art.
[0126] With reference to FIG. 29a, an intraocular lens 500a is
shown centered along an optical axis OA and spaced in the posterior
direction from a convex corneal surface 502a. A retinal target is
also shown centered along the optical axis OA posteriorly from the
intraocular lens 500a. An angular incoming light beam 506a,
schematically composed of a plurality of individual light rays, is
shown refracting and reflecting off both the corneal surface 502a
and the intraocular lens 500a. Specifically, a plurality of rays
508a reflect off the corneal surface, while a further plurality of
rays 510a reflect off the intraocular lens. A large majority of the
light is refracted correctly, as seen by light rays 512a, reaching
the target retinal surface 504a, while only a small portion of the
light 514a is refracted incorrectly to the retinal surface 504a.
Although this so-called "pattern glare" exists, it is very low and
the local contrast is very close to zero.
[0127] Similarly, in FIG. 29b an intraocular lens 500b is shown
centered along an optical axis OA and spaced in the posterior
direction from a convex corneal surface 502b. A retinal target is
also shown centered along the optical axis OA posteriorly from the
intraocular lens 500b. An angular incoming light beam 506b,
schematically composed of a plurality of individual light rays, is
shown refracting and reflecting off both the corneal surface 502b
and the intraocular lens 500b. As with FIG. 29a, a plurality of
rays 508b reflect off the corneal surface, while a further
plurality of rays 510b reflect off the intraocular lens 500b. A
large majority of the light is refracted correctly, as seen by
light rays 512b, reaching the target retinal surface 504b, while
only a small portion of the light 514b is refracted incorrectly to
the retinal surface 504b. Again, the pattern glare is very low and
the local contrast is very close to zero.
[0128] The intraocular lenses 500a and 500b are both molded
silicone lenses having a central, circular optic portion that has a
peripheral edge with anterior and posterior square corners. The
optic portion of both lenses 500a and 500b is roughened or frosted
over its entire exterior surface except in the central optically
refractive region. These lenses are both biconvex in the central
optically refractive region. The peripheral edge of each of the
lenses is a cylindrical surface centered on the optical axis. The
diameter of the optic portion of the lens 500a is 6.00 mm, while
the diameter of the optic portion of the lens 500b is 5.50 mm.
[0129] FIG. 30 illustrates a ray tracing model of an intraocular
lens 600 not made in accordance with the present invention;
specifically, the lens model is denoted 60ACSC and manufactured by
Alcon. The lens has an optic portion which is similarly configured
to the optic portions of the lenses 500a and 500b, but is only
roughened on the outer or peripheral edge surface.
[0130] FIG. 30 illustrates an optical system comprising the
intraocular lens 600, a convex corneal surface 602, and the target
retinal surface 604. An incoming light beam 606 schematically shown
as a plurality of individual light rays first reflects at 608 off
the corneal surface 602. A majority of the light beam 606 refracts
through the intraocular lens 600 shown at 612, but there is some
pattern glare as seen at 614 that strikes the retinal surface 604.
The magnitude of the glare for the lens 600 is an order of
intensity higher than the glare in the intraocular lens models of
FIGS. 29a and 29b, and the glare local contrast is also much
higher.
[0131] In addition to the location of roughening, an important
consideration when manufacturing intraocular lenses in accordance
with the present invention is the magnitude of roughness or
frosting. The magnitude of roughness can be defined in a number of
ways, depending on how the roughness or surface irregularity is
configured. That is, in a preferred embodiment the surface
roughness is formed randomly on the lenses of present invention,
and has no regular repeating patterns. The magnitude of such random
surface roughness could be measured in terms of actual
peak-to-valley dimension, but is typically quantified by its
so-called light scattering level. The scattering level of any
surface refers to its ability to scatter incoming light rather than
directly transmit that light. Therefore, a surface with a
scattering level of 100% does not directly transmit any light
therethrough. In a preferred embodiment, the intraocular lenses of
the present invention have partially opaque or roughened surfaces
that have an 80% scattering level. Of course, other surface
configurations can produce such a magnitude of scattering. The
magnitude of the preferred random roughening is desirably visible
to the naked eye, and appears as a white, cloudy, or "frosted"
surface. At a minimum, the roughening is desirably visible at an
optical magnification of 10.times., but is more desirably visible
to the naked eye.
[0132] The present invention contemplates economical manufacturing
techniques for forming the roughened surfaces on intraocular
lenses, especially for molded silicone lenses. Specifically, the
mold used to shape the lens can be left with a roughened surface
which is then molded directly into the periphery of the optic
portion of the lens. In a preferred embodiment, the internal
surface finish of the mold is formed by electrodiode manufacturing
(EDM) and has a finish of 70 rms, which is a measure of roughness.
Optic pins in the center of the mold form the smooth optically
refractive surfaces. Once the silicone lens is removed from the
mold, it is essentially in finished form with the surface roughness
remaining around periphery of the central optic. If the lens is
made from a lathing process, the machine lines could be left on the
lens and the machine line area masked off so that the optically
refractive portions can then be polished to shape. The machine
lines from the lathe could be optimized during manufacturing to
enhance the roughness.
[0133] While this invention has been described with respect to
various specific examples and embodiments, it is to be understood
that the invention is not limited thereto and that it can be
variously practiced within the scope of the following claims.
* * * * *