U.S. patent application number 16/870182 was filed with the patent office on 2020-11-26 for polymeric material for accommodating intraocular lenses.
The applicant listed for this patent is LensGen, Inc.. Invention is credited to Thomas Silvestrini, Kevin Yacoub.
Application Number | 20200369853 16/870182 |
Document ID | / |
Family ID | 1000005016213 |
Filed Date | 2020-11-26 |
United States Patent
Application |
20200369853 |
Kind Code |
A1 |
Silvestrini; Thomas ; et
al. |
November 26, 2020 |
POLYMERIC MATERIAL FOR ACCOMMODATING INTRAOCULAR LENSES
Abstract
The disclosure relates generally to a polymeric material for use
in accommodating intraocular lenses for implantation in a lens
chamber of a subject's eye. The present disclosure is directed to a
polymeric material which comprises a fluorosilicone polymer and a
silica component. The presently disclosed polymeric material is
both optically clear and has a sufficiently low Young's modulus
such that it can effectively respond to the eye's natural
accommodative forces and thus can be used in accommodating
intraocular lenses. When used in the fabrication of an intraocular
lenses, the polymeric material disclosed herein protect the
physical characteristics of the lens as the added hydrophobicity of
the fluorosilicone polymer allows it to effectively resist
diffusion of fluid from the eye and the adhesion of biologica
materials.
Inventors: |
Silvestrini; Thomas; (Alamo,
CA) ; Yacoub; Kevin; (Irvine, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LensGen, Inc. |
Irvine |
CA |
US |
|
|
Family ID: |
1000005016213 |
Appl. No.: |
16/870182 |
Filed: |
May 8, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15513502 |
Mar 22, 2017 |
10647831 |
|
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PCT/US2015/051512 |
Sep 22, 2015 |
|
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16870182 |
|
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|
62054303 |
Sep 23, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08L 83/00 20130101;
A61F 2/16 20130101; C08K 5/5403 20130101; C08K 2201/006 20130101;
A61L 27/18 20130101; C08G 77/12 20130101; C08L 83/08 20130101; C08J
2383/08 20130101; C08K 3/36 20130101; C08G 77/24 20130101; C08J
3/24 20130101; C08G 77/20 20130101 |
International
Class: |
C08K 3/36 20060101
C08K003/36; C08G 77/20 20060101 C08G077/20; C08G 77/24 20060101
C08G077/24; C08L 83/08 20060101 C08L083/08; C08L 83/00 20060101
C08L083/00; C08K 5/54 20060101 C08K005/54; A61F 2/16 20060101
A61F002/16; A61L 27/18 20060101 A61L027/18; C08J 3/24 20060101
C08J003/24 |
Claims
1. (canceled)
2. A fluorosilicone base composition comprising: a fluorosilicone
polymer; and up to about 30 weight % of a silanized fumed silica
component, wherein the silanized fumed silica component has a
surface area of at least about 280 m.sup.2/g; and wherein the
fluorosilicone polymer comprises a polymer of formula (II):
##STR00004## wherein: n and m are each independently 0 to about
500; t is about 100 to about 1000; each R.sup.1 is independently
alkyl or aryl; R.sup.2 is haloalkyl; R.sup.3 is alkyl or haloalkyl;
and R.sup.4 and R.sup.5 are aryl.
3. The fluorosilicone base composition of claim 2, wherein the
silanized fumed silica component has a surface area of from about
280 m.sup.2/gram to about 350 m.sup.2/g.
4. The fluorosilicone base composition of claim 2, comprising about
20% to about 27% of the silanized fumed silica component.
5. The fluorosilicone base composition of claim 2, wherein R.sup.2
is 3,3,3-trifluoropropyl.
6. The fluorosilicone base composition of claim 5, comprising at
least about 25 mole % trifluoropropyl content.
7. A method of making a crosslinked polymeric material, comprising
the steps of: (a) adding a crosslinking agent and a curing agent to
the fluorosilicone base composition of claim 2; and (b) curing the
fluorosilicone base composition to obtain the cross linked
polymeric material.
8. The method of claim 7, wherein step (a) comprises: adding the
crosslinking agent to a first portion of the fluorosilicone base
composition, and adding the curing agent to a second portion of the
fluorosilicone base composition, and mixing the first and second
portions prior to step (b).
9. The method of claim 8, wherein the first portion of the
fluorosilicone base composition further comprises an inhibitor.
10. The method of claim 7, wherein the curing agent is a platinum
catalyst.
11. The method of claim 7, wherein the silanized fumed silica
component has a surface area of from about 280 m.sup.2/g to about
350 m.sup.2/g.
12. The method of claim 7, wherein the crosslinking agent is a
methylhydrosiloxane-dimethylsiloxane copolymer.
13. The method of claim 12, wherein the crosslinking agent has a
chain length of from about 5 to about 30 repeating Si units.
14. The method of claim 7, wherein R.sup.2 is
3,3,3-trifluoropropyl.
15. An intraocular lens comprising a crosslinked polymeric material
made according to the method of claim 7.
16. The intraocular lens of claim 15, wherein the crosslinked
polymeric material has a refractive index of from about 1.35 to
about 1.40.
17. The intraocular lens of claim 15, wherein the crosslinked
polymeric material has a percent elongation of from about 400% to
about 1000%.
18. The intraocular lens of claim 15, wherein the crosslinked
polymeric material has a Young's modulus of from about 10 psi to
about 150 psi.
19. The intraocular lens of claim 15, wherein the crosslinked
polymeric material has a Young's modulus from about 50 psi to about
100 psi.
20. An intraocular lens (IOL) device comprising: (a) a first lens
comprised of the crosslinked polymeric material made by the method
of claim 7 having a first Young's modulus; (b) a second lens in
spaced relation to the first lens along a central optical axis; and
(c) a circumferential portion encircling the first and second lens,
the circumferential portion comprising an outer peripheral edge;
wherein at least one of a portion of the second lens and a portion
of the circumferential portion is made of a material having a
second Young's modulus; and wherein the first Young's modulus is
less than the second Young's modulus.
Description
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 15/513,502, filed Mar. 22, 2017, which is a
U.S. national phase application of International Application No.
PCT/US2015/051512, filed Sep. 22, 2015, which claims the benefit of
priority to U.S. Provisional Patent Application No. 62/054,303,
filed Sep. 23, 2014. All of the foregoing applications are hereby
incorporated by reference herein under 37 CFR 1.57 in their
entireties.
FIELD
[0002] The disclosure relates generally to a polymeric material for
use in accommodating intraocular lenses for implantation in a lens
chamber of a subject's eye.
BACKGROUND
[0003] Surgical procedures on the eye have been on the rise as
technological advances permit for sophisticated interventions to
address a wide variety of ophthalmic conditions. Patient acceptance
has increased over the last twenty years as such procedures have
proven to be generally safe and to produce results that
significantly improve patient quality of life.
[0004] Cataract surgery remains one of the most common surgical
procedures, with over 16 million cataract procedures being
performed worldwide. It is expected that this number will continue
to increase as average life expectancies continue to rise.
Cataracts are typically treated by removing the crystalline lens
from the eye and implanting an intraocular lens ("IOL") in its
place. As conventional IOL devices are primarily focused for
distance visions, they fail to correct for presbyopia and reading
glasses are still required. Thus, while patients who undergo a
standard IOL implantation no longer experience clouding from
cataracts, they are unable to accommodate, or change focus from
near to far, from far to near, and to distances in between.
[0005] Surgeries to correct refractive errors of the eye have also
become extremely common, of which LASIK enjoys substantial
popularity with over 700,000 procedures being performed per year.
Given the high prevalence of refractive errors and the relative
safety and effectiveness of this procedure, more and more people
are expected to turn to LASIK or other surgical procedures over
conventional eyeglasses or contact lenses. Despite the success of
LASIK in treating myopia, there remains an unmet need for an
effective surgical intervention to correct for presbyopia, which
cannot be treated by conventional LASIK procedures.
[0006] As nearly every cataract patient also suffers from
presbyopia, there is convergence of market demands for the
treatment of both these conditions. While there is a general
acceptance among physicians and patients of having implantable
intraocular lens in the treatment of cataracts, similar procedures
to correct for presbyopia represent only 5% of the U.S. cataract
market. There is therefore a need to address both ophthalmic
cataracts and/or presbyopia in the growing aging population.
SUMMARY
[0007] The present disclosure is directed to a polymeric material
which comprises a fluorosilicone polymer and a silica component.
The presently disclosed polymeric material is both optically clear
and has a sufficiently low Young's modulus such that it can
effectively respond to the eye's natural accommodative forces and
thus can be used in accommodating intraocular lenses. When used in
the fabrication of an intraocular lenses, the polymeric material
disclosed herein protect the physical characteristics of the lens
as the added hydrophobicity of the fluorosilicone polymer allows it
to effectively resist diffusion of fluid from the eye and the
adhesion of biological materials.
[0008] Accordingly, in one aspect, provided herein is a polymeric
material comprising a fluorosilicone polymer and up to about 30
weight % of a silica component, wherein the silica component has a
surface area of at least about 280 m.sup.2/g.
[0009] In another aspect, provided herein is an implantable
intraocular lens (IOL) comprising a polymeric material comprising a
fluorosilicone polymer and up to about 30 weight % of a silica
component, wherein the silica component has a surface area of at
least about 280 m.sup.2/g.
[0010] In still another aspect, provided herein is an intraocular
lens (IOL) device comprising a fluorosilicone polymer and up to
about 30 weight % of a silica component, wherein the silica
component has a surface area of at least about 280 m.sup.2/g. In
one aspect, the intraocular lens (IOL) device comprises [0011] (a)
a first lens comprised of a fluorosilicone polymer and up to about
30 weight % of a silica component, wherein the silica component has
a surface area of at least about 280 m.sup.2/g having a first
Young's modulus; [0012] (b) a second lens in spaced relation to the
first lens along a central optical axis; and [0013] (c) a
circumferential portion encircling the first and second lens, the
circumferential portion comprising an outer peripheral edge;
[0014] wherein at least one of a portion of the second lens and a
portion of the circumferential portion is made of a material having
a second Young's modulus; and wherein the first Young's modulus is
less than the second Young's modulus.
[0015] Other objects, features and advantages of the described
embodiments will become apparent to those skilled in the art from
the following detailed description. It is to be understood,
however, that the detailed description and specific examples, while
indicating various embodiments of the present invention, are given
by way of illustration and not imitation. Many changes and
modifications within the scope of the present invention may be made
without departing from the spirit thereof, and the invention
includes all such modifications.
DETAILED DESCRIPTION
[0016] Specific, non-limiting embodiments of the present invention
will now be described with reference to the drawings. It should be
understood that such embodiments are by way of example and are
merely illustrative of but a small number of embodiments within the
scope of the present invention. Various changes and modifications
obvious to one skilled in the art to which the present invention
pertains are deemed to be within the spirit, scope and
contemplation of the present invention as further defined in the
appended claims.
Polymeric Material
[0017] The present disclosure is directed to a polymeric material
comprising a fluorosilicone polymer and a silica component which is
both optically clear and has a sufficiently low modulus such that
it can effectively respond to the eye's natural accommodative
forces and thus be used in accommodating intraocular lenses.
[0018] In one embodiment, the presently disclosed polymeric
material comprises a fluorosilicone polymer and up to about 30
weight % of a silica component. The fluorosilicone polymer
described herein is a crosslinked copolymer of dialkyl, diphenyl or
phenylalkyl siloxane and a fluorinated dialkyl siloxane. Typically,
the fluorosilicone polymer is a crosslinked copolymer of dialkyl,
diphenyl or phenylalkyl siloxane and trifluoroalkyl(alkyl)siloxane,
but can be a terpolymer or higher order polymer of diphenyl and/or
phenylalkyl siloxane, dialkyl siloxane and
trifluoroalkyl(alkyl)siloxane. In certain embodiments, the
fluorosilicone polymer is a crosslinked copolymer of dialkyl
siloxane, such as dimethyl siloxane, and
trifluoroalkyl(alkyl)siloxane, such as 3,3,3-trifluoropropylmethyl
siloxane. The ratio of dialkyl siloxane and
trifluoroalkyl(alkyl)siloxane can be adjusted to tune the physical
properties of the fluorosilicone polymer. For example, increasing
the trifluoroalkyl(alkyl)siloxane can increase the hydrophobicity
of the resulting fluorosilicone polymer. In some embodiments, the
fluorosilicone polymer typically comprises at least about 25 mole %
trifluoroalkyl(alkyl)siloxane, or about 25 mole %
trifluoroalkyl(alkyl)siloxane, or about 30 mole %
trifluoroalkyl(alkyl)siloxane, or about 35 mole %
trifluoroalkyl(alkyl)siloxane, or about 40 mole %
trifluoroalkyl(alkyl)siloxane, or about 50 mole %
trifluoroalkyl(alkyl)siloxane or from about 25 mole % to about 50
mole %, or from about 25 mole % to about 40 mole %
trifluoroalkyl(alkyl)siloxane.
[0019] In one embodiment, the fluorosilicone polymer is represented
by formula (I):
##STR00001##
wherein:
[0020] n and m are each independently 0 to about 500;
[0021] t is about 100 to about 1000;
[0022] each R.sup.1 is independently alkyl or aryl;
[0023] R.sup.2 is haloalkyl;
[0024] R.sup.3 is alkyl or haloalkyl;
[0025] R.sup.4 and R.sup.5 are independently alkyl, haloalkyl or
aryl; and
[0026] each X is a crosslinker which links the polymer of formula
(I) with a second polymer of formula (I).
[0027] In one embodiment, n is about 50, or about 100, or about
125, or about 150, or about 200, or about 250, or about 300, or
about 350, or about 400, or about 450, or about 500. In one
embodiment, m is about 50, or about 100, or about 125, or about
150, or about 200, or about 250, or about 300, or about 350, or
about 400, or about 450, or about 500. In another embodiment, n is
about 100, and m is about 150.
[0028] In any embodiment, t is about 100, or about 125, or about
150, or about 200, or about 250, or about 300, or about 350, or
about 400, or about 450, or about 500, or about 550, or about 600,
or about 650, or about 700, or about 750, or about 800, or about
850, or about 900, or about 950, or about 1000.
[0029] In one embodiment, each R.sup.1 is alkyl. Suitable alkyl
groups include, but are not limited to, C.sub.1-C.sub.6 alkyl
groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl,
n-pentyl, n-hexyl, and the like. In another embodiment, each
R.sup.1 is methyl. In one embodiment, R.sup.3 is alkyl, such as
defined for R.sup.1. In another embodiment, R.sup.3 is methyl. In
one embodiment, R.sup.4 is alkyl, such as defined for R.sup.1. In
another embodiment, R.sup.4 is methyl. In one embodiment, R.sup.5
is alkyl, such as defined for R.sup.1. In another embodiment,
R.sup.5 is methyl. In yet another embodiment, R.sup.4 and R.sup.5
are methyl. In still another embodiment, the fluorosilicone polymer
is represented by formula (IA):
##STR00002##
wherein:
[0030] n is from 1 to about 500;
[0031] m is from 0 to about 500;
[0032] t is about 100 to about 1000;
[0033] R.sup.2 is haloalkyl;
[0034] R.sup.3 is alkyl or haloalkyl; and
[0035] each X is a crosslinker which links the polymer of formula
(IA) with a second polymer of formula (IA).
[0036] In one embodiment, R.sup.2 is a haloalkyl group comprising
from 1 to 3 halo (provided at least one is fluoro) substituents.
Exemplary haloalkyl groups include, but are not limited to,
fluoromethyl, 2-fluorethyl, 2,2-difluoroethyl, and
3,3,3-trifluoropropyl. In one embodiment, R.sup.2 is
3,3,3-trifluoropropyl.
[0037] The crosslinker is typically a
methylhydrosiloxane-dimethylsiloxane copolymer with a
methyl-hydrogen content of from about 30 to about 70 mole %. In
some embodiments, the crosslinker has a chain length of from about
5 to about 30 repeating Si units (i.e., degree of
polymerization).
[0038] In certain embodiments, the polymeric material provided
herein has a degree of polymerization of from about 200 to about
500, or from about 300 to about 500, or about 400, or about
450.
[0039] In order to be used as an intraocular lens material, the
polymeric material described herein should be optically clear.
However, the fluorosilicone polymer and the silica component are
not index matched. Thus the optical properties of the polymeric
material must be maintained as the modulus is increased.
Advantageously, the optical properties of the presently disclosed
polymeric material can be tuned independently from the modulus.
Several different factors contribute to the optical properties of
the polymeric material, including the amount and particle size of
the silica component.
[0040] Since the refractive index of the fluorosilicone polymer is
low, it is contemplated that the particle size of the silica
component should be as small as possible in order to obtain
superior optical characteristics. In certain embodiments, the
polymeric material provided herein has a refractive index of from
about 1.35 to about 1.40, or from about 1.37 to from about 1.39, or
about 1.38. Accordingly, the silica component as used herein has a
surface area of at least about 280 m.sup.2/g, or at least about 300
m.sup.2/g, or at least about 310 m.sup.2/g, or at least about 320
m.sup.2/g, or at least about 330 m.sup.2/g, or at least about 340
m.sup.2/g, or at least about 350 m.sup.2/g. In certain embodiments,
the silica component has an average particle size of less than
about 11 nanometers. Fumed silica having an average particle size
of about 7 nanometers in diameter is particularly suitable because
the small particle size does not interfere with the wavelength of
visible light and contributes to an improved optical resolution in
the cured composition. Commercial fumed silica with particle sizes
as low as 7 nm are commercially available (e.g., CABOT and Sigma).
Typically, the silica component is present in an amount up to about
30 weight %, or 27 weight %, or about 25 weight %, or about 23
weight %, or about 20 weight %, or from about 20 to about 30 weight
%.
[0041] The silica component as used herein is fumed or "activated"
silica, which has been treated with a silazane. The amount of
silica component should be such that the polymeric material is
sufficiently reinforced, yet remains optically clear. Suitable
silazanes and methods for carrying out the fumed silica treatment
include the in situ reaction of small particle size fumed silica
and are well known in the art. In such reactions, the silazane
(e.g., hexamethyldisilazane) readily reacts with the hydroxyl
functionalities on fumed silica, forming a trimethylsiloxane
coating on the silica surface. In certain embodiments, the
polymeric material provided herein has a Young's modulus of from
about 10 psi to about 150 psi, or from about 50 psi to about 100
psi, or about 70 psi.
[0042] Other physical characteristics of the polymeric material can
be modulated as well. In certain embodiments, the polymeric
material provided herein has a tensile strength of from about 500
psi to about 1200 psi, or from about 700 psi to about 1000 psi, or
about 900 psi. In certain embodiments, the polymeric material
provided herein has a percent elongation of from about 400% to
about 1000%, or about 600%.
[0043] Also provided herein are methods for making the
above-described polymeric material. In certain embodiments, the
method comprises the steps of:
[0044] (a) combining a vinyl end-capped fluorosilicone polymer with
up to about 30 weight % of a silica component, wherein the silica
component has a surface area of at least about 280 m.sup.2/g, to
obtain a fluorosilicone base composition;
[0045] (b) adding a crosslinking agent and a curing agent to the
fluorosilicone base composition; and
[0046] (c) curing the fluorosilicone base composition to obtain the
polymeric material.
[0047] The vinyl end-capped fluorosilicone polymer can be
synthesized using known methods from commercially available
starting materials or purchased from commercial sources. For
example, a vinyl end-capped
trifluoropropylmethylsiloxane--dimethylsiloxane copolymer having a
molecular weight of about 25,000 to about 35,000--is commercially
available from Gelest. Alternatively, the vinyl end-capped
fluorosilicone polymer can be synthesized as described in Example
1, for example. Suitable starting materials include, but are not
limited to, alkylsiloxanes (e.g., octamethylcyclotetrasiloxane),
haloalkylsiloxanes (e.g., trifluoropropyltrimethylcyclosiloxane),
and the like. Suitable vinyl endblockers include, but are not
limited to, vinyl-endblocked dimethyl siloxane oligomer.
[0048] In one embodiment, the fluorosilicone polymer has a long
chain length, having a molecular weight of greater than 35,000
daltons, or greater than 50,000 daltons and, or greater than 70,000
daltons are desired.
[0049] In one embodiment, the fluorosilicone polymer is a compound
of formula (II):
##STR00003##
wherein:
[0050] n and m are each independently 0 to about 500;
[0051] t is from about 100 to about 1000;
[0052] each R.sup.1 is independently alkyl or aryl;
[0053] R.sup.2 is haloalkyl;
[0054] R.sup.3 is alkyl or haloalkyl; and
[0055] R.sup.4 and R.sup.5 are independently alkyl, haloalkyl or
aryl.
[0056] The polymeric material described herein has a degree of
crosslinking such that the material has a sufficiently low modulus
to minimize any potential deformation caused by forces applied
during its use as, for example, an accommodating intraocular lens,
yet also be sufficiently solid as to minimize the permeation of the
gel. In certain embodiments, the polymeric material is lightly
crosslinked, having less than about 5 parts per hundred (pph)
crosslinker, or less than about 4 pph, or less than about 2 pph, or
less than about 1 pp, or about 1 pph. The crosslinker is typically
a methylhydrosiloxane-dimethylsiloxane copolymer with a
methyl-hydrogen content of from about 30 to about 70 mole %. In
some embodiments, the crosslinker has a chain length of from about
5 to about 30 repeating Si units (i.e., degree of
polymerization).
[0057] In one embodiment, the curing step comprises adding a
platinum catalyst. The platinum group metal catalyst can be any of
the compatible platinum group metal-containing catalysts known to
catalyze the addition of silicone-hydrogen atoms to silicon-bonded
vinyl radicals. Platinum group metal-containing catalysts can be
any of the known forms which are compatible, such as platinic
chloride, salts of platinum, chloroplatinic acid and various
complexes, for example, silicone complexes with platinum
metal-containing groups. The platinum group metal-containing
catalyst can be used in any catalytic quantity, such as in an
amount sufficient to provide at least about 0.1 ppm weight of
platinum group metal (as elemental metal) based on the total weight
of the composition. In certain embodiments, at least about 10 ppm,
or at least about 20 ppm, or at least 30 ppm, or at least about 40
ppm by weight of platinum catalyst was used.
Implantable Intraocular Lens (IOL)
[0058] A device implanted in the eye naturally becomes exposed to
the fluid in the eye and the fluid can, over time, diffuse through
the device and have unintended and/or undesired effects on the
physical characteristics of the device. Attempts have been made to
coat ophthalmic devices with barrier layers to prevent such
diffusion, but these procedures can be costly and time consuming.
In addition, if an ophthalmic device contains a chamber or channel
within the device which contains a fluid, there is a risk that that
fluid can diffuse out of its fluid chamber and into the polymeric
material. This results in a decrease in the amount of fluid that
can be utilized by the IOL, as well as to possibly alter the
physical characteristics of the polymeric material.
Fluorocarbon-containing silicone monomers can enhance a polymer's
resistance to the diffusion of fluid, and as such, the polymeric
material described herein can be used in ophthalmic devices to
resist the diffusion of fluid into or out of the device.
[0059] The IOLs can be fabricated from the disclosed polymeric
material using known molding techniques, such as disposable or
polished stainless steel mold, having a mold cavity in the shape
required for the correct refraction of light for the material. In
practice, the uncured fluorosilicone base composition is introduced
into the mold cavity, in an amount dictated by considerations
relating to the lens size, refractive power, and structure, and
then cured. Several methods of molding the lens can be employed,
including injection molding, liquid injection molding, compression
molding, and transfer molding.
Intraocular Lens (IOL) Device
[0060] The presently disclosed intraocular lenses can be used in an
intraocular device for implantation in a patent. Such devices are
known in the art, and include, for example, those described in U.S.
Pat. Nos. 7,662,180 and 7,875,661.
[0061] In certain embodiments, the presently disclosed intraocular
lenses can be used as a power changing lens in a two-part
accommodating IOL device in which the power changing lens and a
primary lens are in sliding contact with one another within a lens
chamber. In such systems, the power changing lens is sized and
shaped to take on and respond to the radially-inward forces which
are applied along the peripheral edge of the lens. In contrast, the
primary lens does not participate in providing an accommodative
response and thus is sized and shaped so as to avoid interfering or
resisting the radial compressive forces that are applied to the
power changing lens. This may be accomplished by controlling the
relative diameters and thicknesses of the power changing lens and
the primary lens to maximize the extent to which the radial
compressive forces are applied onto the power changing lens and to
minimize the extent to which these forces are applied onto the
primary lens.
[0062] Accordingly, in one embodiment, provided herein is an
intraocular lens (IOL) device comprising:
[0063] (a) a first lens comprised of the polymeric material as
described herein having a first Young's modulus;
[0064] (b) a second lens in spaced relation to the first lens along
a central optical axis; and
[0065] (c) a circumferential portion encircling the first and
second lens, the circumferential portion comprising an outer
peripheral edge;
[0066] wherein at least one of a portion of the second lens and a
portion of the circumferential portion is made of a material having
a second Young's modulus; and wherein the first Young's modulus is
less than the second Young's modulus.
[0067] In practice, the first lens (i.e., the power changing lens)
and the second lens (i.e., the primary lens) are in sliding contact
with one another within a lens chamber. The lens chamber is filled
with a fluid or gel having specific physical and chemical
characteristics to enhance the range of refractive power provided
by the IOL during accommodation. The fluid or gel is selected such
that it cooperates with the power changing lens in providing a
sufficient range of accommodation of up to at least 3 diopters,
preferably up to at least 5 diopters, preferably up to at least 10
diopters and most preferably up to at least 15 diopters.
[0068] In addition, a lens comprised of the polymeric material
described herein has a reduced likelihood of buckling in a patient
from contact with the primary lens as the surface is significantly
more oleophobic than other polymers typically used for IOLs.
[0069] In addition to use in an IOL, the polymeric material of the
present disclosure can also be used in other ophthalmic devices
such as, but not limited to, contact lenses, keratoprostheses,
capsular bag extension rings, corneal inlays, corneal rings, or
other ophthalmic devices. An exemplary alternative use would be in
the field of breast implants, such that the polymers can be used as
an exterior shell-like material to prevent leakage of an internal
material.
EXAMPLES
Example 1
[0070] An exemplary polymeric material according to the present
disclosure was prepared as follows.
[0071] Vinyl Endblocked 40 Mole % Fluorosilicone Polymer
[0072] A vinyl endblocked 40 mole % fluorosilicone polymer for use
in the fluorosilicone base was prepared as follows. 140 parts
octamethylcyclotetrasiloxane (D4 cyclics), 100 parts
trifluoropropyltrimethylcyclosiloxane (D3 fluorocyclics), 3.2 parts
vinyl-endblocked dimethyl siloxane oligomer (vinyl endblocker), and
0.1 parts potassium siloxanolate catalyst were agitated in a
polymerization vessel and heated to about 150.degree. C. At
150.degree. C., potassium siloxanolate catalyst was added to the
polymerization vessel. Once polymerization was visually observed by
an increased viscosity, polymerization was continued for about 3
hours.
[0073] After about 3 hours, the catalyst was de-activated by
purging polymer with CO.sub.2 for 1 hour and the polymer exposed to
reduced pressure (minimum of 27'' Hg vacuum) at a temperature of
from about 150.degree. C. to about 180.degree. C. until the
volatile content reached an amount below about 3%.
[0074] Fluorosilicone Base
[0075] 100 parts of the vinyl endblocked 40 mole % fluoro silicone
polymer, 9 parts hexamethyldisilizane (HMDZ) and 3 parts water were
added to a mixing vessel (e.g., sigma blade mixer). Once mixed, 60
parts activated silica (Tokuyama QS-30C fumed silica) was added in
multiple additions until the silica was fully mixed into the
fluorosilicone polymer. The composition was mixed at 80.degree. C.
for about 30 minutes, at which time the mixing vessel was heated to
about 150.degree. C. for about 3 hours under vacuum.
[0076] After about 3 hours, the heat and vacuum were removed. While
the fluorosilicone base was still hot, additional fluorosilicone
polymer was slowly added to the polymerization vessel until the
silica content was reduced to approximately 25 parts. The
fluorosilicone base was then dispersed in chlorinated solvent
(i.e., perchloroethylene) to approximately 30% solids content,
filtered through 1 micron media filter and subjected to heat and
vacuum to remove solvent.
[0077] Polymeric Material Comprising a Fluorosilicone Polymer
[0078] Equal parts of A and B (Table 1) were mixed together, vacuum
de-aired, and press cured in an ASTM test slab mold for about 10
minutes at 302.degree. F. Cured test slab was allowed to
equilibrate at room temperature for a minimum of 3 hours.
TABLE-US-00001 TABLE 1 Part A Part B 100 part fluorosilicone 100
parts base fluorosilicone base 5-15 ppm platinum 2 parts methyl
hydrogen catalyst siloxane crosslinker 0.3 pph methyl vinyl
cyclosilicone inhibitor
[0079] Mechanical properties of the fluorosilicone polymer are
shown in Table 2. Surprisingly, the fluorosilicone polymer as
described herein exhibits an enhanced tensile strength while
maintaining a low modulus when compared to a non-fluorinated
silicone polymer. In addition, it is contemplated that the
fluorosilicone polymer described herein maintains a suitable
optical clarity due to the low silica content.
TABLE-US-00002 Fluorosilicone Non-fluorinated polymer silicone
polymer Durometer (Shore A) 20 20 Tensile strength 900 psi 475 psi
% elongation 600% 300% 100% modulus 70 psi 65 psi
[0080] The invention described and claimed herein is not to be
limited in scope by the specific preferred embodiments disclosed
herein, as these embodiments are intended as illustrations of
several aspects of the invention. Indeed, various modifications of
the invention in addition to those shown and described herein will
become apparent to those skilled in the art from the foregoing
description. Such modifications are also intended to fall within
the scope of the appended claims.
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