JP2014104239A - Intraocular lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intraocular lens using a gelatinous material with good transparency and excellent strength.SOLUTION: In an intraocular lens that includes an optical part with a predetermined refractive power, and a support part for holding the optical part intraocularly, the optical part is composed of acrylic resin or acrylamide resin, and the support part is composed of acrylamide resin. The acrylamide resin is formed by copolymerization of an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer in the presence of a crosslinking agent.

Description

  The present invention relates to a soft intraocular lens using a transparent and high refractive index gel material.

  Conventionally, an intraocular lens that is installed in the eye after removing the crystalline lens is known. The intraocular lens is composed of an optical part having a predetermined refractive power and a support part that supports the optical part in the eye, and the turbid lens that has become a cataract is removed from the lens capsule by ultrasonic emulsification aspiration. After removal, the lens is replaced by fixing and supporting the intraocular lens in the lens capsule. In recent years, an intraocular lens having an intraocular accommodation has been studied. As an intraocular lens having such an adjustment force, a gel-like elastic member is bonded between two optical parts and the optical part, and both optical parts are adjusted according to the tension and relaxation of the ciliary muscle. One that obtains an adjustment force by changing the distance between the axes is known (see Patent Document 1).

JP 2006-305070 A

  The gel-like elastic member used to change the distance between the axes of the two optical parts in this way has flexibility so that the lens can move in the axial direction, and ensures a certain degree of elasticity. There is a need. On the other hand, in order to fold such an intraocular lens into a small size and insert it into the eye, it is necessary to have strength that can withstand deformation during folding. Furthermore, in addition to using such a gel-like elastic member as a joining member between lenses, in order to use the role of a support part for fixing and holding a lens in a sac or as a material of an optical part, strength, transparency Various factors such as property and refractive index must be considered.

  In view of the above-described problems of the prior art, an object of the present invention is to provide an intraocular lens using a gel material having good transparency and excellent strength.

In order to solve the above problems, the present invention is characterized by having the following configuration.
(1) In an intraocular lens having an optical part having a predetermined refractive power and a support part for holding the optical part in the eye, the optical part is made of an acrylic resin or an acrylamide resin, The support portion is made of an acrylamide resin.
(2) The acrylamide resin used for the support is formed by copolymerizing an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer in the presence of a crosslinking agent.
(3) The resin used in the optical part is an acrylamide resin, and the acrylic resin is formed by copolymerizing an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer in the presence of a crosslinking agent. It is characterized by being.
(4) The acrylamide-based hydrophilic monomer used as the composition of the optical part and the support part is N, N′-dimethylacrylamide.
(5) The acrylic hydrophobic monomer used as the composition of the optical part and the support part is an acrylate containing an alkyl group having 12 to 18 carbon atoms or a derivative thereof in the side chain.

  According to the present invention, it is possible to obtain an intraocular lens using a gel material having good transparency and excellent strength.

  An embodiment of the present invention will be described. FIG. 1 is a schematic diagram showing an example of an intraocular lens of the present embodiment, and FIG. 2 is a schematic diagram showing a cross section of the intraocular lens shown in FIG. The intraocular lens 1 of the present embodiment includes an optical unit 2 having a predetermined refractive power and a support unit 3 for fixing and holding the optical unit 2 in the eye such as a sac. In the present embodiment, the optical unit is composed of two optical units (first optical unit 2a and second optical unit 2b) having a predetermined refractive power, and the support unit 3 joins both optical units 2a and 2b. At the same time, it plays the role of holding the optical part in the eye. In addition, the support part 3 also serves as a role as an elastic member for changing the distance between the axes of the joined optical parts.

  The optical part 2 (2a, 2b) and the support part 3 of the present embodiment are made of a transparent shape memory gel, and the transparent shape memory gel used for the support part 2 is an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer. Can be obtained by copolymerization in the presence of a crosslinking agent.

  Specific examples of acrylamide-based hydrophilic monomers used in the composition of transparent shape memory gel include N, N-dimethylacrylamide, acrylamide, isopropylacrylamide, N- (hydroxymethyl) acrylamide, hydroxyethylacrylamide, acrylic acid, acrylic Sodium acid or the like can be used. In particular, since N, N-dimethylacrylamide is liquid at room temperature, it can be copolymerized without a solvent, and the reaction proceeds uniformly without inhibiting the reaction of the solvent. Moreover, if a solvent is not used, both the maximum stress and the maximum strain can be increased.

  As the acrylic hydrophobic monomer used as the composition of the transparent shape memory gel, for example, an acrylate or methacrylate having a side chain of an alkyl group having 8 to 18 carbon atoms or a derivative thereof as a hydrophobic group can be used. Specific examples include stearyl acrylate, lauryl acrylate, isodecyl acrylate, isooctyl acrylate, tridecyl acrylate, stearyl methacrylate, lauryl acrylate, isodecyl methacrylate, isooctyl methacrylate, tridecyl methacrylate, and methyl methacrylate. In particular, lauryl acrylate and stearyl acrylate can be preferably used. Moreover, it is possible to use any chemical structure that has crystallinity even if it contains aromatic or unsaturated as an acrylic hydrophobic monomer.

  Examples of the crosslinking agent include dimethacrylic acid esters such as ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, diethylene glycol dimethacrylate, and triethylene glycol dimethacrylate, N, N′-methylenebisacrylamide, divinylbenzene, and other intraocular. The material which can be used as a crosslinking agent for preparation of a lens base material is mentioned.

  In addition, various cross-linked network structures used to create gels with excellent mechanical properties, such as those developed in recently developed ring gels, nanocomposite gels, double network gels, and cross-crosslinked network gels, can be used. . In other words, a cyclic cross-linking structure with cyclic molecules using cyclodextrin, etc. for cyclizing gels, a polyfunctional end-crosslinking structure with clay particles for nanocomposite gels, an interpenetrating network structure with two types of polymers for double network gels, and an intercrosslinking network. A gel has a network structure in which two or more kinds of polymers are crosslinked only between different kinds of polymers.

  Using these monomers as raw materials, copolymerization is carried out in the absence of a solvent or in the presence of a solvent such as ethanol. The amount ratio of the acrylamide hydrophilic monomer and the acrylic hydrophobic monomer can be, for example, in a molar ratio of 10: 1 to 1: 1 (acrylamide hydrophilic monomer: acrylic hydrophobic monomer). In order to increase the transparency, it is better to decrease the ratio of the acrylic hydrophobic monomer, and it is preferably about 10: 1 to 3: 1.

  The amount of the crosslinking agent can be, for example, in the range of 0.005 to 5 mol% with respect to the total amount of monomers (in this embodiment, the total amount of acrylamide hydrophilic monomer and acrylic hydrophobic monomer). The polymerization method is not particularly limited, but can be synthesized by radical polymerization, for example. As the reaction initiator (polymerization initiator), a photopolymerization initiator is preferable. For example, it can be used as a polymerization initiator for forming intraocular lens base materials such as benzophenone, α-ketoglutaric acid, benzoin, methylorthobenzoylbenzoate, and acetophenone. Materials.

  In addition, although both the optical part and the support part can be formed using the above-mentioned materials, the support part is harder than the optical part, and when it is desired to improve the strength, the composition of the transparent shape memory gel is used. The main material is the acrylamide hydrophilic monomer used, and the secondary material is an acrylic hydrophobic monomer that has a glass transition temperature higher than that of the acrylic hydrophobic monomer used in the optical part. A transparent shape memory gel can be obtained.

  Further, the curvatures of the first optical unit 2a and the second optical unit 2b are respectively determined so that a desired refractive power can be obtained for the entire intraocular lens 1. In the intraocular lens 1 of the present embodiment, as shown in FIG. 2, the front side (anterior eye side) when the intraocular lens 1 is inserted into the crystalline lens capsule of the patient's eye is a convex lens (positive lens). Although a certain first optical member 2a and a second optical member 2a having a concave lens (negative lens) on the rear side are used, the present invention is not limited to this. What is necessary is just to select the combination with which the adjustment function of the intraocular lens 1 acts suitably with the combination of lenses of various shapes, such as a convex lens, a concave lens, a meniscus lens. Further, since the first optical part 2a and the second optical part 2b are respectively joined to the support part 3 as shown in the figure, the joining positions of the optical parts (the rear surface of the first optical part 2a and the front surface of the second optical part 2b). The joining portion is preferably a flat surface. Further, the shape of the support portion is not limited to that shown in FIG. 1, and an elastic force based on the shape can be obtained in addition to the elastic force due to the material. For example, as shown in FIG. 3, a support portion 4 having a substantially arcuate cross-sectional shape can be used.

  In addition, the bonding agent for bonding the first optical unit 2a and the second optical unit 2b with the support unit 3 causes the optical unit 2 and the support unit 3 to swell after the intraocular lens 1 is placed on the crystalline lens capsule. As long as the optical member is peeled off and no axial displacement occurs, and the intraocular lens is inserted, the optical member only needs to have a bonding force that does not peel off due to the folding of the intraocular lens (optical part, support part). Such a bonding agent has good biocompatibility, and a known adhesive that does not attack the material of the intraocular lens base material can be used. Moreover, the monomer of the material used for the optical part 2 and the support part 3 can be mixed, and this can be used as a bonding agent, and an optical part, a support part, and a bonding agent can also be joined by copolymerization.

  In addition, when joining the 1st optical part 2a and the 2nd optical part 2b, and the support part 3, it joins in the state which made the optical axis of both optical parts correspond. In addition, when joining, as shown in FIG. 1, the intraocular body fluid can penetrate into the internal space formed between the first optical unit 2a and the second optical unit. It is preferable to join them with a gap.

  Moreover, the formation of such an optical part (the first optical part 2 and the second optical part 2a), for example, by pouring a mixture of monomers to be an intraocular lens base material into a mold and curing it by polymerization, A desired shape may be obtained, or a desired shape may be obtained by cutting after a monomer liquid mixture is polymerized and cured into a plate shape or a rod shape. The same applies to the formation of the support portion 3. In addition, the shape of the optical part and the support part must be considered so as to have a desired shape in a completely water-containing state (used state). It is also possible to obtain a polymer in a three-dimensional manner by irradiating the monomer solution with light.

  In the present embodiment, an example in which two optical units are used as intraocular lenses is shown, but the present invention is not limited to this. For example, the transparent shape memory of this embodiment is used for a one-piece type, a three-piece type, or a refilling type intraocular lens in which a loop-like or plate-like support part is provided on a single optical part like a conventional intraocular lens. A gel may be used. The optical part is a hydrophobic or hydrophilic soft acrylic base material used as a base material for an intraocular lens, a silicone resin or a hydrogel, and the transparent shape memory gel of the present invention has a support part (two or more It can also be used only for including a support part for joining and supporting the optical part. In addition, when using such a gel for a support part, it does not need to be transparent.

  Examples of hydrophobic acrylic materials used in the optical part include acrylic acid ester monomers such as methyl acrylate, ethyl acrylate, propyl acrylate, 2-ethylhexyl acrylate, and butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. Methacrylic acid ester monomers. Examples of the hydrophilic acrylic material include hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate and the like. By polymerizing one or more of these materials in combination, a hydrophobic or hydrophilic soft acrylic substrate can be obtained.

Hereinafter, examples relating to the transparent shape memory gel used in the present embodiment will be described in detail, but the present invention is not limited to these examples.
<Example 1>
N, N′-dimethylacrylamide as a monomer is 0.75 M, stearyl acrylate (SA) is 0.25 M, N, N′-methylenebisacrylamide is 0.05 mol% as a cross-linking agent, and benzophenone is 0. Weighed and mixed at a ratio of 1 mol%. The mixture was stirred for 15 minutes under inert gas (nitrogen gas). After that, the mixed liquid stirred is poured into a transparent mold prepared in advance, and irradiated with an ultraviolet lamp for 24 hours, so that the base having a shape imitating a one-piece plate type intraocular lens in which an optical part and a support part are formed is formed. A material (gel) was obtained. Transparency, bending and restoration were evaluated in a state where the obtained base material was sufficiently hydrated.
In the bending, it was evaluated whether the optical part could be further folded in a state where the support part was bent using an insulator and placed on the optical part. Furthermore, the optical part folded in the state in which the support part was placed was released from the insulator, and it was evaluated whether both the optical part and the support part could be restored to the original state without damage. If it was possible to bend and restore without breakage, it was rated as ○. In addition, the refractive index was measured and evaluated by a tensile test. The refractive index was measured using a refractometer (RA-600 manufactured by Kyoto Electronics Industry Co., Ltd.) at 23 ° C. and D line. The tensile test was performed at 23 ° C. using a desktop material testing machine (STA-1150, manufactured by Orientec Corp.). The results are shown in Table 1.

<Example 2>
0.75M N, N'-dimethylacrylamide as monomer, 0.05M lauryl acrylate (LA), 0.2M stearyl acrylate, 0.05Mol% N, N'-methylenebisacrylamide as a cross-linking agent, polymerized Benzophenone as an initiator was weighed at a ratio of 0.1 mol% and mixed. The mixture was stirred for 15 minutes under inert gas (nitrogen gas). In the same manner as in Example 1, the mixture was poured into a predetermined mold, irradiated with an ultraviolet lamp for 24 hours, and a base material (gel) imitating a one-piece plate type intraocular lens in which an optical part and a support part were formed ) The same evaluation as Example 1 was performed with respect to the obtained base material. The results are shown in Table 1.
<Example 3>
As monomers, N, N'-dimethylacrylamide is 0.75M, lauryl acrylate is 0.1M, stearyl acrylate is 0.15M, N, N'-methylenebisacrylamide is used as a crosslinking agent, and 0.05Mol% as a polymerization initiator. Benzophenone was weighed at a ratio of 0.1 mol% and mixed. The mixture was stirred for 15 minutes under inert gas (nitrogen gas). In the same manner as in Example 1, the mixture was poured into a predetermined mold, irradiated with an ultraviolet lamp for 24 hours, and a base material (gel) imitating a one-piece plate type intraocular lens in which an optical part and a support part were formed ) The same evaluation as Example 1 was performed with respect to the obtained base material. The results are shown in Table 1.

<Comparative Example 1>
Weigh and mix 1M N, N'-dimethylacrylamide as monomer, 0.05Mol% N, N'-methylenebisacrylamide as crosslinking agent, and 0.1Mol% α-ketoglutaric acid as polymerization initiator. did. The mixture was stirred for 15 minutes under inert gas (nitrogen gas). In the same manner as in Example 1, the mixture was poured into a predetermined mold, irradiated with an ultraviolet lamp for 24 hours, and a base material (gel) imitating a one-piece plate type intraocular lens in which an optical part and a support part were formed ) The same evaluation as Example 1 was performed with respect to the obtained base material. The results are shown in Table 1.

Results: All the gels prepared in Examples 1 to 3 had good transparency, and the bending and restoration were good without breakage. The refractive index of the gel obtained in this embodiment is higher than the refractive index of water (about 1.33), and it was confirmed that the conditions were such that it could be used as a lens in vivo.

It is the schematic diagram which showed the external appearance of the intraocular lens of this embodiment. It is the schematic diagram which showed the cross section of the intraocular lens of this embodiment. It is the figure which showed the example of a change of the support part in the intraocular lens of this embodiment.

1 Intraocular lens 2 Optical part 3 Support part

Claims (5)

In an intraocular lens having an optical part having a predetermined refractive power and a support part for holding the optical part in the eye, the optical part is made of an acrylic resin or an acrylamide resin, and the support part is An intraocular lens comprising an acrylamide resin. The acrylamide resin used for the support part is formed by copolymerizing an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer in the presence of a crosslinking agent. The intraocular lens described. The resin used for the optical part is an acrylamide resin, and the acrylic resin is formed by copolymerizing an acrylamide hydrophilic monomer and an acrylic hydrophobic monomer in the presence of a crosslinking agent. The intraocular lens according to claim 2. The intraocular lens according to claim 3, wherein the acrylamide-based hydrophilic monomer used as the composition of the optical part and the support part is N, N'-dimethylacrylamide. The eye according to claim 4, wherein the acrylic hydrophobic monomer used as a composition of the optical part and the support part is an acrylate containing an alkyl group having 12 to 18 carbon atoms or a derivative thereof in a side chain. Inner lens.