RU2253482C1 - Monolithic solid artificial lens - Google Patents

Abstract

FIELD: ophthalmology.

SUBSTANCE: in monolithic solid artificial lens, containing optical and supporting polymer material portions, said polymer material is prepared by hardening composition containing oligocarbonate methacrylate, oligourethane methacrylate, and benzyl methacrylate in specified proportions.

EFFECT: enabled manufacture of monolithic solid lens having improved optical properties and shape memory without mechanical treatment.

2 dwg, 1 tbl, 5 ex

Description

The invention relates to medicine, and specifically to ophthalmology.

Currently, in ophthalmology are used lenses made of various materials with good optical properties. However, almost all well-known world companies produce monolithic lenses, both hard and elastic, by turning. Moreover, as is known from the world literature on the chemistry of macromolecular compounds, the main chains of the polymer break, which subsequently causes the thermal oxidative degradation of the polymer. Worldwide data from clinical trials do not contradict this fact, since the occurrence of secondary cataract occurs within 20-40% precisely on lenses made by turning. In this regard, the most promising monolithic lenses made without the use of mechanical processing, for example, by photochemical technology (US patents 5725576 and 5833890).

Known artificial lens of the eye (patent No. 2132662) with haptic elements made of polymer fiber, such as polypropylene. However, this lens does not have sufficient reliability of fixing the haptic elements in the thickness of the optical part and, in addition, the polymer fiber used for the haptic part does not have sufficient resistance to the action of biologically active liquids (chamber moisture of the eye) and often causes a toxicological reaction from surrounding tissues, especially in children.

Known IOL of a polymeric material made by photo-curing the composition (patent No. 2129880, taken as a prototype), prepared from a mixture of oligourethane methacrylate of the following structure:

M = -CH ₂ -CH ₂ -OC (O) -C (CH ₃ ) = CH ₂ , m = 60-150

octyl methacrylate:

CH ₂ = C (CH ₃ ) —C (O) —O— (CH ₂ ) ₇ —CH ₃

oligocarbonate methacrylate:

CH ₂ = C (CH ₃ ) —C (O) O (CH ₂ ) ₂ —O — C (O) —O— (CH ₂ ) ₂ —O— (CH ₂ ) ₂ —O — C (O) - O- (CH ₂ ) ₂ —O — C (O) —C (CH ₃ ) = CH ₂

2,2-dimethoxy-2-phenylacetophenone:

2,4-ditretbutylorthoquinone:

while the above components are taken in the following ratio, mass%:

2,2-dimethoxy-2-phenylacetophenone 0.1-0.7

2,4-ditretbutylorthoquinone 0.001-0.006

octyl methacrylate 8.0-42

oligocarbonate methacrylate 2.0-8.0

oligourethane methacrylate the rest

The disadvantage of this invention is that the prototype can only produce elastic lenses, which cannot fully satisfy the needs of ophthalmic practice, since there is a large proportion of operations in which implantation of only a solid lens is indicated.

The technical problem solved by the invention is the creation of a monolithic hard crystalline lens without mechanical processing with improved optical properties and shape memory, which is stored up to a temperature of at least 70 ° C.

The stated technical problem is solved in that in a monolithic artificial lens containing the optical and supporting parts of a polymeric material, the polymeric material is made by curing a composition containing the oligocarbonate methacrylate structure:

CH ₂ = C (CH ₃ ) —C (O) O (CH ₂ ) ₂ —O — C (O) —O— (CH ₂ ) ₂ —O— (CH ₂ ) ₂ —O — C (O) - O- (CH ₂ ) ₂ —O — C (O) —C (CH ₃ ) = CH ₂

2,2-dimethoxy-phenylacetophenone structure:

C ₆ H ₅ -C (O) -C (CH ₃ ) ₂ -C ₆ H ₅

2,4-Ditretbutylorthoquinone structure:

oligourethane methacrylate structure:

CH ₂ = C (CH ₃ ) —C (O) O (CH ₂ ) ₂ —O — C (O) —NH — C ₆ H ₅ (CH ₃ ) —NH — C (O) - (- O — C (CH ₃ ) —CH ₂ -) _n —C (O) —NH — C ₆ H ₅ (CH ₃ ) —NH — C (O) —O— (CH ₂ ) ₂ —O — C (O) —C (CH ₃ ) = CH ₂ ; n = 30-40

benzyl methacrylate structure:

CH ₂ = C (CH ₃ ) —C (O) —O — CH ₂ —C ₆ H ₅

while the above components are taken in the following ratio, mass%:

2,2-dimethoxy-2-phenylacetophenone 0.1-0.7

2,4-ditretbutylorthoquinone 0.001-0.006

oligourethane methacrylate 12-18

benzyl methacrylate 8-12

oligocarbonate methacrylate rest

After curing, we obtain an optically transparent lens with improved optical properties and shape memory, which remains at a temperature not lower than 70 ° C.

In patentable compositions, the set of minimum values of the ingredients determines the threshold value from the point of view of the minimum below which either the required resolution of the lens is not achieved, or the polymerization process is not fully implemented, or the necessary strength of the haptic elements is not achieved, which leads to acute reactions in the tissues of the eye or decentralization of the lens.

The maximum values of the ingredients are determined by the fact that, at high values, either a deterioration in its optical characteristics (distortion of shape, the appearance of turbidity, etc.) or the appearance of excessive rigidity of the haptic elements, which leads to trauma to the surrounding tissues of the eye, is manifested.

Example 1. In a reaction flask equipped with a stirrer, the components are sequentially introduced in the following ratio, g

oligourethane methacrylate (amount of hydroxypropylene

groups m = 36) 15.19

benzyl methacrylate 10.6

oligocarbonate methacrylate 73.58

2,2-dimethoxy-2-phenylacetophenone 0.6265

2,4-ditretbutylorthoquinone 0.0035

The resulting mixture was stirred at room temperature for 40 minutes until complete dissolution of 2,2-dimethoxy-2-phenylacetophenone and 2,4-ditretbutylorthoquinone.

After mixing, the composition is filtered off and pumped out using a vacuum pump at a pressure of 0.5-1 mm Hg. until gas evolution ceases.

The evacuated composition is used to make an IOL.

IOLs are made in quartz injection molds consisting of two halves (Fig. 1), a detailed description of which is given in RF patent No. 2074673. The lower halves of the molds are positioned horizontally so that the recesses under the optical part are on top. On the surface place restrictive gaskets made in the form of a ring of sheet Teflon with a thickness of 150 microns. A pre-prepared composition using a microdoser with a volume of 200 μl is introduced into the recesses of the lower halves of the injection molds. The upper halves of the injection molds are applied to the lower ones and pressed so that the composition completely fills the entire volume between the two halves of the injection molds, limited by the gasket. Filling of injection molds is carried out at room temperature, yellow lighting, in a dust-free atmosphere. Each of the injection molds is successively placed under a microscope of the MBS-10 type, and at a 12-fold increase by moving the lower half relative to the upper one, the edge of the optical part of the upper half is aligned with the edge of the optical part of the lower half of the injection mold. The combined injection mold is tightly compressed and fixed. The injection mold is transferred to an exposure unit consisting of a light source (a DRT-120 mercury-quartz lamp), a diaphragm, an optical system that allows you to project the open part of the diaphragm onto the working surface of the injection mold, and a device that allows you to open the diaphragm at a given speed. The mold is placed in the exposure unit so that the incident beam passes along the main optical axis of the optical part of the mold, and the image of the diaphragm is formed in a plane separating the two halves of the mold. At the initial time, the diaphragm is closed. The aperture opening speed is set corresponding to an increase in the radius of the illuminated area of the optical part by 3.5 mm in 7 minutes, and the first exposure stage is carried out.

At the first stage of exposure, the optical part of the IOL is formed. The injection mold is transferred under the second exposure unit, consisting of a source (a mercury-quartz lamp of the DRT-120 brand) and a collimator, and the second stage of exposure is carried out. The optimal exposure time is selected empirically so that after the manifestation of the IOL, the linear dimensions of the supporting elements coincide with the corresponding dimensions indicated in figure 2. When the light intensity incident on the surface of the injection mold is 440 W / m ^{2, the} optimal exposure time is 1 min 30 s.

At the second stage of exposure, the supporting elements of the IOL (haptic part) are formed. After irradiation, the injection mold is disassembled, separating one half of the mold from the other and removing the restrictive pad. Further, all operations are performed with a half of the injection mold on which the IOL is formed. The IOL form is placed in a development unit consisting of 200 ml developer cuvettes, a developer circulation pump, and a nozzle located in the cuvette lid. The form with the IOL is placed in a cuvette, the developer isopropyl alcohol is poured, closed with a lid and the pump is turned on. The manifestation time of the IOL is 2 minutes. During the development, the non-polymerized part of the photocurable material is removed, which during exposure was under the parts of the pattern that were opaque to UV light and made on the inner surface of the upper half of the injection mold (Fig. 2). After development, the IOL form is dried in a stream of warm dedusted air for 5 minutes. The IOL form is placed in a 100 ml cuvette with double-distilled water heated to 40-60 ° C. The cuvette is transferred to an exposure unit consisting of a source (a mercury-quartz lamp of the DRT-120 brand), and an annealing stage is carried out, which consists in additional irradiation of the IOL. When the intensity of the light incident on the surface of the IOL, 330 W / m ² the exposure time is 10 minutes. After additional irradiation, the IOL is dried from water and separated from the mold. Obtained are optically transparent elastic IOLs, the characteristics of which are given in Table 1.

Example 2. The composition is prepared as, in example 1, with the following ratio of components, g:

oligourethane methacrylate (amount of hydroxypropylene

groups m = 33) 12,899

benzyl methacrylate 11.02

oligocarbonate methacrylate 75.98

2,2-dimethoxy-2-phenylacetophenone 0.1

2,4, -ditretbutylorthoquinone 0.001

An IOL is made, as in Example 1. The characteristics of the IOL are shown in Table 1.

Example 3. The composition is prepared, as in example 1, in the following ratio of components, g:

oligourethane methacrylate (amount of hydroxypropylene

groups m = 38) 16,294

benzyl methacrylate 9.78

oligocarbonate methacrylate 73.22

2,2-dimethoxy-2-phenylacetophenone 0.7

2,4-ditretbutylorthoquinone 0.006

An IOL is made, as in Example 1. The characteristics of the IOL are shown in Table 1.

Example 4. The composition is prepared, as in example 1, in the following ratio of components, g:

oligourethane methacrylate (amount of hydroxypropylene

groups m = 26) 24.14

benzyl methacrylate 1

oligocarbonate methacrylate 74

2,2-dimethoxy-2-phenylacetophenone 0.85

2,4-ditretbutylorthojicon 0.01

An IOL is made, as in Example 1. The characteristics of the IOL are shown in Table 1.

Example 5. The composition is prepared, as in example 1, in the following ratio of components, g:

oligourethane methacrylate (amount of hydroxypropylene

groups m = 56) 3.9

benzyl methacrylate 20

oligocarbonate methacrylate 76

2,2-dimethoxy-2-phenylacetophenone 0.05

2,4-ditretbutylorthoquinone 0,0003

An IOL is made, as in Example 1. The characteristics of the IOL are shown in Table 1.

Table 1 Photo material following the example Refractive index Density, g / cm ³ Resolution, lin / mm The limiting temperature to which the shape recovery occurs, ° С Geometric shape 1 1,5 1.34 220 90 is recovering 2 1,5 1.34 220 95 is recovering 3 1,5 1.34 220 90 is recovering 4 1.4985 1.30 150 35 not restored 5 1,507 1.30 130 fifty not restored

Note: the refractive index, density and resolution of the IOL are determined by the methods described in the patent of the Russian Federation No. 2074673. Tests to determine the limiting temperature and restore the geometric shape were carried out as follows: the lenses were placed in a water tank equipped with a thermostat with temperature control in the range from 20 to 100 ° C; Then, the load was applied so that the haptic elements straightened along the longitudinal axis of the lens, the load was fixed and the lens was heated for 10 minutes to a temperature of 20 ° C, then it was slowly cooled, the load was removed and the geometric shape of the lenses was checked. Then the same tests were carried out in the temperature range 25 ° С-100 ° С with an interval of 5 ° С and the maximum temperature was determined for each composition of the photocurable composition to which the geometric shape of the lenses is completely restored.

From table 1 it follows that in all examples (1, 2, 3), in which the composition of the photocurable composition corresponds to the claims, a lens is formed having improved optical properties (resolution) and shape memory, which is stored up to a temperature of at least 70 ° C. Deviations in the recipe (examples 4, 5) lead to the deterioration of all measured characteristics.

Figure 1 shows a General view of the injection mold in the assembled state; figure 2 is a bottom view of the inner surface of the upper half of the form without the lower half. The mold consists of the lower 1 and upper 2 halves; 3 - an annular gasket, 4 - a transparent section corresponding to the optical part of the lens; 5 is a transparent section corresponding to the supporting elements of the lens; 6 - opaque areas corresponding to the technological holes of the lens.

Claims (1)

A monolithic solid artificial eye lens containing the optical and supporting parts from a polymer material obtained by photocuring a composition containing a structure of oligocarbonate methacrylate CH ₂ = C (CH ₃ ) —C (O) O (CH ₂ ) ₂ —O — C (O) —O— (CH ₂ ) ₂ —O— (CH ₂ ) ₂ —O — C (O) - O- (CH ₂ ) ₂ —O — C (O) —C (CH ₃ ) = CH ₂ , 2,2-dimethoxy-phenylacetophenone structure C ₆ H ₅ —C (O) —C (CH ₃ ) ₂ —C ₆ H ₅ , 2,4-ditretbutylorthoquinone structure

oligourethane methacrylate structure CH ₂ = C (CH ₃ ) —C (O) O (CH ₂ ) ₂ —OC (O) —NH — C ₆ H ₅ (CH ₃ ) —NH — C (O) - (- OC (CH ₃ ) -CH ₂ -) _n -C (O) -NH-C ₆ H ₅ (CH ₃ ) -NH-C (O) -O- (CH ₂ ) ₂ -OC (O) -C (CH ₃ ) = CH ₂ characterized in that the polymer material is made by photocuring a composition containing a benzyl methacrylate structure

and oligourethane methacrylate with the number of hydroxypropylene groups n = 30-35; while the above components are taken in the following ratio, wt.%: 2,2-Dimethoxy-2-phenylacetophenone 0.1-0.7 2,4-Ditretbutylorthoquinone 0.001-0.006 Oligourethane methacrylate 12-18 Benzyl Methacrylate 8-12 Oligocarbonate methacrylate Else

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