JP2000325369A - Artificial cornea - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heal and match with an eye tissue satisfactorily, prevent the progress of downgrowth, the reduction of transparency (light) of an optical part due to downgrowth, floating-up from a condition in which an artifical cornea is embedded and planted, and a possibility of dropping, and supply nutriment from aqueous humor to the eye tissue in a support part. SOLUTION: This artificial cornea 1 has an optical part 2 made of an optically transparent material and a support part 3 having minute clearance structure to surround at least a part of the optical part 2 and support it and is provided with a collar part 4 which covers a rear face of the support part 3 to come into contact with it and protrudes to the outside more than the support part 3. A through-hole 5 is provided in the collar part 4 in contact with the support part 3 and/or the collar part 4 protruding to the outside more than the support part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an artificial cornea. More specifically, the present invention relates to an artificial cornea used to replace the lost cornea or replace the lost cornea due to an eye tissue disease or the like and restore visual function.

[0002]

2. Description of the Related Art Artificial corneas are generally transparent (translucent).
It is composed of an optical part made of a material and a supporting part for supporting the optical part by fixing the optical part to human eye tissue. As such an artificial cornea, the present inventors have already comprised an optical part which is a transparent (translucent) material and a support part surrounding the optical part, and have a surface inside the eye when the artificial cornea is implanted. There has been proposed an artificial cornea in which a collar portion protruding radially outward is provided on a support portion on the side to be deformed (International Publication No. WO98 / 20813).

[0003] According to the artificial cornea, the artificial cornea and the ocular tissue are well fused via the supporting portion, and downgrowth (at the wound site, the corneal tissue is moved from the incision wound surface facing the supporting portion to the posterior surface of the artificial cornea. The growth of the corneal prosthesis is prevented, and the growth (growth toward the corneal cornea) of the implanted artificial cornea is prevented from decreasing due to the growth tissue covering the posterior surface of the optic part due to the downgrowth. An excellent effect of reducing the possibility of lifting and falling off was exhibited, and various problems of the conventional artificial cornea were solved.

[0004] The supporting portion of the artificial cornea proposed by the present inventors is used as a suture site between the artificial cornea and the host eye tissue at the time of implantation surgery. When the eye tissue enters the supporting portion, it also plays a role of physically and firmly bonding the artificial cornea and the eye tissue.

However, in order to stably implant the artificial cornea over a long period of time, it is necessary for the ocular tissue that has entered the supporting portion to perform normal metabolism, and for this purpose, an appropriate amount of nutrients is supplied to the ocular tissue. There must be. In general, sources of nutrients to corneal tissue include aqueous humor, tears, and the pericorneal vascular network, of which the primary source is aqueous humor. However, in the artificial cornea proposed by the present inventors, a brim portion exists between the support portion and the aqueous humor, and when the brim portion is formed of a material impermeable to a material, the support portion is formed. The supply of nutrients from the aqueous humor to the invading eye tissue is interrupted.

[0006] As described above, the supply of nutrients from the aqueous humor is cut off at the collar, and there is a risk that ocular tissue that has entered the support may be necrotic. Thus, it cannot be said that there is no possibility that the bonding force between the artificial cornea and the host eye tissue is weakened.

[0007] Further, since a part of the collar part is located inside the eye of a part of the host cornea, the part of the cornea in contact with the collar part is also blocked from contact with the aqueous humor, resulting in malnutrition. The thickness of the cornea may be reduced. It cannot be said that there is no possibility that this may contribute to the loss of the artificial cornea.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in an attempt to further improve the artificial cornea, which has been already proposed, and has a good fusion with ocular tissues and further prevents the progress of downgrowth. In addition, there is no possibility that the downgrowth causes a decrease in the transparency (transparency) of the optical part, and there is no possibility of rising and falling off from the implanted state. It is an object of the present invention to provide an artificial cornea capable of supplying nutrients of the present invention.

[0009]

According to the present invention, there is provided an optical section made of an optically transparent material, and a supporting section having a fine gap structure for surrounding and supporting at least a part of the optical section. An artificial cornea having a collar portion that covers and contacts a rear surface of the support portion and protrudes outward from the support portion, wherein the collar portion and / or the support portion contact the support portion. The present invention relates to an artificial cornea, wherein a through-hole is provided in a collar portion protruding outward.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the artificial cornea of the present invention has an optical portion made of an optically transparent material, and has a fine gap structure and surrounds and supports at least a part of the optical portion. And a flange that covers and contacts the rear surface of the support, and that protrudes outward from the support. The collar is in contact with the support and / or the support. A through-hole is provided in a flange portion protruding outward from the portion.

The optical part used for the artificial cornea of the present invention is made of an optically transparent material. Such an optical part is located substantially at the center of the artificial cornea, and fulfills its visual function by maintaining transparency (light transmission).

The material used for the optical part is harmless to the human body and excellent in safety because the inner surface (rear surface) of the artificial cornea may come into direct contact with the aqueous humor in the eye. It is preferable to use a material used as a material that comes into contact with a living body or is implanted in a living body, such as a contact lens or an intraocular lens.

Examples of the above materials include acrylic resins represented by, for example, polymethyl methacrylate;
Non-water-containing materials such as acrylic elastomers represented by polybutyl acrylate and the like, polyesters, polyurethanes, and silicones represented by polyethylene terephthalate; water-containing materials such as poly 2-hydroxyethyl methacrylate, polyvinyl alcohol, and poly N-vinyl pyrrolidone Materials may be used, and one or more of these materials may be selected and used.

The planar shape of the optical section is not particularly limited, and may be any shape as long as there is no problem in practical use. However, the optical section has a mechanical strength and is prevented from being deformed by pressure from the eye. In addition, in the case of ordinary corneal transplantation, a circular shape is preferable in consideration of the fact that a corneal replacement part is often punched out with a circular trepan.

If the optical section has a circular planar shape, the diameter cannot be determined unequivocally because the diameter varies depending on the size of the portion of the eye tissue to be replaced with the artificial cornea. The reason for this is that the diameter between the ends of the support portion (the outer diameter of the support portion) differs depending on the size of the tissue diameter to be replaced. It is determined in consideration of the width of the supporting portion where the sex and cell invasiveness can be expressed. In consideration of these facts, furthermore, from a practical point of view, the diameter of the optical portion is usually preferably about 2 to 8 mm, more preferably about 3 to 6 mm.

The thickness of the optical section is preferably at least about 0.05 mm from the viewpoint of mechanical strength. Such a thickness may be changed by changing the thickness of the central portion and the peripheral portion when the refractive power is given as necessary.
For example, at least a part of the optical unit may be a spherical surface. In particular, when a lens power is given to the optical unit, spherical surfaces having different curvatures may be provided on the front surface and the rear surface of the optical unit.

Since it is difficult to suture the optical section directly to eye tissue, a support section is used to fix the optical section in the eye.

The support section has a fine gap structure and is provided so as to surround and support at least a part of the optical section.

Since the support used in the present invention has a fine gap structure, after the artificial cornea is implanted, the surrounding eye tissue penetrates into the fine gap of the support, and the artificial cornea and the eye tissue are formed. As a result, it becomes strongly bound with affinity.

Further, in the present invention, it is preferable that the supporting portion has flexibility. The flexibility of the support portion facilitates suturing with ocular tissue, facilitates adaptation to the incision shape of the host ocular tissue, and reduces physical compression on the host ocular tissue.

The supporting portion has a mechanical strength to the extent that it is not torn by suturing, has a gap through which the surrounding eye tissue can physically enter, and is firmly adhered to the eye tissue by fusion. In addition, it is preferable that the material is excellent in biocompatibility. it can.

Examples of the above-mentioned materials include acrylic resins represented by, for example, polymethyl methacrylate, and the like.
Non-water-containing materials such as acrylic elastomers represented by polybutyl acrylate and the like, polyesters represented by polyethylene terephthalate and the like, polyurethane, silicone, polypropylene, Teflon; poly-2-hydroxyethyl methacrylate, polyvinyl alcohol;
A water-containing material such as poly-N-vinylpyrrolidone; a biological material such as collagen; and the like, one or more of which are selected and used.

Examples of the form of the support having a fine gap structure include a nonwoven fabric and a sponge having an open cell structure produced by freeze-drying or foaming.

The average pore size of the fine pores into which cells can enter is described in Jean T. Jacob-LaBa
rre et al. (Progress in Biomedic)
alPolymers, Plenum Press, N
ew York, P.E. 27-39, (1990)). Therefore, the support portion used in the present invention may have a fine gap structure having a gap (gap size) substantially in this range.

The planar shape of the support portion is not particularly limited, and may be any shape as long as there is no problem in practical use. However, the support portion maintains mechanical strength and prevents deformation due to pressure from the eye. For this reason, it is preferable that the concentric ring is used.

In the case where the planar shape of the support portion is a concentric annular shape, the inner diameter is usually equal to the diameter of the optical portion. In addition, the outer diameter of the ocular tissue cannot be determined unequivocally because it varies depending on the size of the site of the ocular tissue to be replaced with the artificial cornea. Is the same as the size of.
The size may be increased by about 5 mm, for example, about 4 to 20 mm, particularly preferably about 5 to 16 mm.

Although the thickness of the supporting portion cannot be specified unconditionally, it is usually about 0.01 to 3 mm, preferably about 0.1 to 0.3 mm.
It is preferably about 2 to 2.5 mm in practical terms. In particular, it is ideal that the thickness of the supporting portion is substantially the same as the thickness of the corneal incision section.

In the present invention, it is preferable to provide the support with a curvature that matches the curvature of the cornea.

Further, some of the materials used for the supporting portion are difficult to adhere to the interface of the gap when the cells derived from the eye tissue proliferate in the minute gaps of the material. However, it is difficult to firmly bind to eye tissue. Therefore, when using such a material, in order to improve the adhesion to cells, the material,
It is preferable that a surface treatment such as plasma treatment; surface graft polymerization; coating of a biological substance such as collagen, laminin, fibronectin or the like or immobilization to a surface be performed in advance. The surface modification of the material means the surface of the material forming the fine gap structure, for example, in the case of a nonwoven fabric, the surface of a fiber, for example, in the case of a sponge having open cells, the surface of the material facing the bubbles. Means a modification to

Further, the artificial cornea of the present invention is provided with a collar portion which covers and contacts the rear surface of the support portion and protrudes outward from the support portion.

In the artificial cornea of the present invention, the presence of the collar allows the collar to cap the wounded corneal incision from the inside of the eye chamber, and the downgrowth (cells from corneal tissue). (Wound to the posterior surface of the artificial cornea) due to the proliferation of the bacteria. As a result, it is possible to more firmly prevent the artificial cornea from rising or falling off, and the cells grown by downgrowth do not reach the rear surface of the optical part, and the excellent transparency (light transmission) of the optical part is achieved. Gender) is reliably maintained.

The material used for the collar portion is harmless to the human body and excellent in safety, and is not particularly limited as long as the object of the present invention can be achieved.
For example, the same material as that used for the optical section, the support section, and the like can be used.

The brim portion protrudes outward from the support portion, and the shape thereof is not particularly limited as long as the shape is excellent in safety and the object of the present invention can be achieved. In order to effectively exhibit the effects of the present invention, it is formed so as to protrude radially outward of the support portion over the entire circumference of the artificial cornea on the side facing the inside of the eye when doing this. preferable.

For example, in order that the effects of the present invention such as maintaining the transparency (transparency) of the optical portion and preventing the artificial cornea from falling off can be sufficiently exhibited, the collar portion may be radiated from the support portion. It is preferable to protrude 0.5 mm or more outward in the radial direction, and in consideration of the ease of insertion into the eye, it is preferable to protrude 2 mm or less,
Usually, it is preferable to project about 1 mm.

The thickness of the collar (in the direction of the optical axis of the eye)
Considering the ease of insertion into the interior of the eye, the distance to the iris, securing the volume of the anterior chamber, etc., in order to eliminate the possibility of adversely affecting the eye, 1 mm or less, preferably 0.1 to
Desirably, it is 0.5 mm.

When the brim portion is viewed from the strength side, the normal intraocular pressure (about 20 mmHg) is up to 50 mm.
It is preferable that the material and the thickness have a strength that can withstand a pressure of Hg without causing extreme deformation. Therefore, from the viewpoint of such strength, for example, the thickness of the collar portion is preferably at least 0.1 mm.

Further, the artificial cornea of the present invention is provided with a through-hole in a brim portion in contact with the support portion and / or a brim portion protruding outward from the support portion. This is one of the major features of the present invention.
One.

[0038] In the artificial cornea of the present invention, the presence of the through-holes allows nutrients for maintaining the ocular tissue, which has entered the fine gaps of the supporting portion, in a favorable state from the aqueous humor. Also, nutrients from the aqueous humor can be supplied to the cornea at the interface between the host cornea and the artificial cornea, where the contact with the aqueous humor has been cut off by the collar. As a result, the supporting portion of the artificial cornea and the ocular tissue are firmly fused to each other, and it is possible to reliably maintain the good state for a long period of time, and the possibility of the artificial cornea floating and falling off is further reduced.

As described above, when the artificial cornea of the present invention is implanted, the support portion and the brim portion do not exist between the layers of the cornea.
The through-hole provided in the collar portion is for supplying nutrients from aqueous humor to the eye tissue and the cornea that have entered the fine gap of the support portion.

It should be noted that focusing solely on the fact that the through-holes are provided, it is conventionally known, for example, from Japanese Patent Laid-Open No. 3-17356.
No. 0, JP-A-5-329200, U.S. Pat. No. 4,624,669, U.S. Pat.
No. 599, U.S. Pat. No. 4,851,003 and the like disclose an artificial cornea having a through hole. None of these conventional artificial corneas have a support having a fine gap structure and a brim for preventing downgrowth, and their structures are completely different from the artificial cornea of the present invention.

When these conventional artificial corneas are implanted, the peripheral portion having a through-hole is provided between the layers of the cornea, and the through-hole serves as a passage for nutrients from the lower cornea to the upper cornea. . On the other hand, when the artificial cornea of the present invention is implanted, the support portion and the brim portion do not exist between the layers of the cornea, and the through hole provided in the brim portion is located near the interface between the eye tissue and the artificial cornea in the support portion. It is a supply channel for nutrients from the aqueous humor to the host cornea.

Therefore, the artificial cornea of the present invention is fundamentally different from the conventional artificial cornea having a through hole in the purpose of setting the through hole.

As described above, the artificial cornea of the present invention is provided with a through-hole at a specific site which has not existed in the past, and the through-hole at this specific site can exhibit the excellent effect as described above.

As described above, the through-hole is provided in the brim portion that comes into contact with the support portion and / or the brim portion that protrudes outward from the support portion, and nutrients from the aqueous humor are more sufficiently provided in the support portion. In view of the fact that the through-hole is easily supplied to the eye tissue, it is particularly preferable that the through-hole is provided in the collar portion that comes into contact with the support portion.

The shape of the through hole is not particularly limited as long as the object of the present invention can be achieved.
Examples include squares and rectangles.

Although the size of the through hole is not particularly limited,
In order to perform the function of transmitting nutrients from aqueous humor,
The area is preferably 1 × 10 ⁻⁶ mm ² or more. To maintain the strength of the collar portion, 100
mm ² or less.

Therefore, the size of the through hole is usually 1 × 10
^-6 100 mm ² approximately, inter alia 1 × 10 ^-2 30 m
It is preferably practically about m ² .

The number of through holes provided in the brim portion is not particularly limited as long as the object of the present invention can be achieved, and the number of through holes may be one or plural.

There is no particular limitation on the state of distribution of the through-holes, but in order to uniformly maintain the metabolism of the cells derived from the eye tissue in the support and the corneal tissue on the brim, Is preferably uniform. In particular, it is preferable that the center of the through hole is uniformly present on a concentric ring centered on the optical part.

There is no particular limitation on the method of forming the through hole in the brim portion. For example, (a) a drilling method using photoetching such as an excimer laser, (b) a drilling method using a drill, a needle, or the like; When molding using a molding machine, an injection molding machine, or the like, there is a method of forming a hole by using an appropriate mold.

Among the above methods, it is particularly preferable to employ (a) a method of forming a through hole by piercing with an excimer laser. This means that when drilling using an excimer laser, the shape and size of the holes can be set relatively easily by selecting the mask appropriately,
For example, even when a mechanical drilling method as shown in (b) cannot be applied due to the physical properties of the material of the brim portion, drilling is possible by using an excimer laser.

The artificial cornea of the present invention comprises an optical part, a support part and a brim part as described above, and is provided with a through-hole in the brim part. To prevent outflow, invasion of bacteria, etc. into the eye, after artificial corneal implantation, for example, conjunctival valve covering, mucosal covering,
It is preferable to apply a coating with an appropriate infection-prevention sheet or the like to part or all of the front surface of the implanted site. By covering the supporting portion of the artificial cornea exposed to the outside with the living tissue or sheet, it is possible to prevent aqueous humor outflow, intraocular infection, and the like.

The provision of a water-impermeable layer on the surface or inside of the support can also prevent the outflow of aqueous humor and the invasion of bacteria and the like into the eye.

Here, an embodiment of the artificial cornea of the present invention will be described with reference to the following drawings.

FIG. 1 is a schematic sectional view showing an embodiment when the artificial cornea of the present invention is implanted in a corneal tissue.

In FIG. 1, an artificial cornea 1 of the present invention is implanted in a corneal tissue 6 and has an optical part 2 having an anterior surface 2b and a posterior surface 2a, and a support part 3 surrounding and supporting the optical part 2. And a flange portion 4 that covers and contacts the rear surface 3a (aqueous humor 7 side) of the support portion 3 and protrudes outward from the support portion 3 and further contacts the support portion 3. A through hole 5 is provided in the brim portion 4.

As described above, since the artificial cornea 1 of the present invention has the brim portion 4, the brim portion 4 caps the corneal incision wound surface 9, which is the wound, from the inner side of the intraocular chamber 8, thereby reducing the keratotomy. The progress of the growth can be physically prevented, and as a result, the rear surface 2a of the optical unit 2 is not covered, and the excellent transparency (transparency) of the optical unit 2 is reliably maintained. There is no possibility that the implanted artificial cornea 1 will rise and fall off. Moreover, the collar 4
Is provided with the through-hole 5, so that nutrients from the aqueous humor 7 can be supplied to the eye tissue that has entered the fine gap in the support portion 3 through the through-hole 5.

In the artificial cornea 1 shown in FIG. 1, the collar portion 4 is integral with a part of the optical portion 2 and is separate from the support portion 3 (which is joined later). In the invention,
The flange portion 4 may be integrated with a part of the optical portion 2 and / or the support portion 3 or may be separate, and there is no particular limitation.

As described above, the artificial cornea of the present invention has a great feature in its through-hole, but the through-hole can be variously modified as shown in FIGS.

FIGS. 2 (a), 3 (a), 4 (a), 5
(A), 6 (a), 7 (a), 8 (a) and 9 (a)
2 is a schematic sectional view showing one embodiment of the artificial cornea of the present invention, and FIGS. 2 (b), 3 (b), 4 (b), 5
(B), 6 (b), 7 (b), 8 (b) and 9 (b)
Respectively correspond to FIGS. 2 (a), 3 (a), 4 (a), 5
(A), 6 (a), 7 (a), 8 (a) and 9 (a)
3 is a schematic plan view corresponding to the schematic cross-sectional view of FIG. Each of these schematic plan views is the posterior surface side of the artificial cornea 1 (the lower side of each schematic sectional view).
It is a view from the point of view.

In FIGS. 2 to 9, the artificial cornea 1 comprises an optical part 2, a support part 3, and a brim part 4, as in FIG.
The flange portion 4 is provided with a through hole 5. The through hole 5 may be provided in the flange portion 4 that comes into contact with the support portion 3 as shown in FIGS. As shown in FIG. 4, it may be provided on a flange portion 4 protruding outside of the support portion 3. For example, the flange portion 4 and the support portion 3 which come into contact with the support portion 3 as shown in FIGS. It may be provided on the brim portion 4 that projects outward.

The artificial cornea 1 shown in FIGS.
The optical part 2 and the brim part 4 are integrated and joined to the support part 3, but the artificial cornea 1 shown in FIG. 9 has the optical part 2, the support part 3 and the brim part 4 as separate bodies. And
These are joined together. However, the artificial cornea of the present invention is not limited to the number of components as described above.

The artificial cornea 1 shown in FIGS. 1 to 9 is provided with a curvature, but the artificial cornea of the present invention is not limited to the presence or absence of the curvature.

The method for producing an artificial cornea of the present invention is not particularly limited, and various methods can be used.

For example, in the artificial cornea 1 shown in FIG. 1, for example, a part in which the optical part 2 and the brim part 4 are integrally formed and the support part 3 are separately manufactured, and these parts are appropriately coated with an adhesive or the like. After joining by using, the flange portion 4 can be perforated to provide a through hole 5. The integrated part of the optical part 2 and the brim part 4 can be obtained by, for example, compression molding, injection molding, cutting, or the like. Further, as described above, for example, a nonwoven fabric, a sponge, or the like can be used for the support portion 3. When an adhesive is used at the time of the joining, it is necessary to ensure that the transparency (transparency) of the optical unit 2 is not impaired.

The artificial cornea of the present invention thus obtained has the above-mentioned structure, so that the artificial cornea is well fused with the eye tissue, further prevents the progress of downgrowth, and the transparency (optical transparency) of the optical part due to the downgrowth. Grease), and there is no possibility of lifting and falling off from the buried state, and it can supply nutrients from aqueous humor to ocular tissue that has entered the support.

[0067]

EXAMPLES Next, the artificial cornea of the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Example 1 [Production of an artificial cornea in which the optical part and the brim part are integrated and the through-hole is provided in the brim part that comes into contact with the support part] FIG. 10A is a schematic cross-sectional view and FIG. The artificial cornea 1 having the shape and dimensions shown in a plan view (as viewed from the back side of the artificial cornea 1 (the lower side of the (a) schematic sectional view)) was produced.

(1) Production of a part in which the transparent optical part 2 and the brim part 4 are integrated A transparent polyether polyurethane is molded by a compression molding machine, and the optical part 2 has a thickness of 0.8 mm and an outer diameter of 4 mm. A part having an outer diameter of 8.5 mm in which the optic part 2 and the rim part 4 were integrated with the thickness of the rim part 4 of 0.3 mm was produced.

(2) Production of Supporting Part 3 A 0.5 mm thick non-woven fabric made of polyether polyurethane (having a basis weight of 50 g / m ² ) was punched out with a trepan into a ring donut shape having an outer diameter of 7 mm and an inner diameter of 4 mm.

(3) Joining of the part in which the optical part 2 and the brim part 4 are integrated to the support part 3 The part in which the optical part 2 and the brim part 4 are integrated is supported using a 1,4-dioxane solvent as an adhesive. The part 3 was adhered as shown in FIG. 10 and was sufficiently dried.

(4) Production of Through Hole 5 by Perforating Collar 4 Excimer laser (laser gas: KrF, oscillation wavelength:
248 nm, device: INDE manufactured by Sumitomo Heavy Industries, Ltd.
X 846 K) to make a hole in the collar part 4,
Ten 0.5 mm × 0.5 mm square through holes 5 shown in FIG. 10 were formed at equal intervals on a concentric ring centered on the optical unit 2.

The obtained artificial cornea 1 was placed on the posterior side (FIG. 10).
(A) The scanning microscope JS manufactured by JEOL Ltd.
As a result of observation with M-5410LV, the support portion 3 could be recognized from the perforated portion (through hole 5) of the brim portion 4.

The artificial cornea thus obtained was sterilized with ethylene oxide gas and implanted in rabbit eyes.
It could be easily sutured with ocular tissue. After that, the progress was observed, and the artificial cornea was firmly fused with the ocular tissue without falling, as well as floating, and the transparency (transparency) of the optical part of the artificial cornea was maintained. Up to
No inflammation such as outflow of aqueous humor in the eye and infection in the eye was observed, and a good condition was maintained.

[0075]

As described above, the artificial cornea of the present invention can be easily sutured to ocular tissue and easily fixed to ocular tissue.
Good fusion with ocular tissue, and further inhibits the progress of downgrowth, and the downgrowth may reduce the transparency (transparency) of the optical part, and may cause the optical part to rise and fall from the implanted state Not only is it possible to supply nutrients from aqueous humor to the ocular tissue that has penetrated into the minute gaps in the support.

As described above, in particular, according to the artificial cornea of the present invention, nutrients from aqueous humor are supplied to the ocular tissue in the supporting portion, so that the cells of the ocular tissue continue to survive and fulfill their cell functions. The state of the tissue in the fine gap can be favorably maintained. This further reduces the possibility of artificial cornea lifting and falling off.

Further, the nutrients supplied from the aqueous humor can be supplied not only to the eye tissue that has entered the support, but also to the host cornea near the interface with the artificial cornea. Therefore, the state of the corneal tissue is maintained well, and the possibility of the artificial cornea rising and falling is further reduced.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment when the artificial cornea of the present invention is implanted in corneal tissue.

FIG. 2 is a schematic view showing one embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIG. 3 is a schematic view showing an embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIG. 4 is a schematic view showing an embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIG. 5 is a schematic view showing one embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIGS. 6A and 6B are schematic views showing one embodiment of the artificial cornea of the present invention, wherein FIG. 6A is a schematic sectional view, and FIG. 6B is a schematic plan view.

FIGS. 7A and 7B are schematic diagrams showing one embodiment of the artificial cornea of the present invention, wherein FIG. 7A is a schematic sectional view, and FIG. 7B is a schematic plan view.

FIG. 8 is a schematic view showing an embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIG. 9 is a schematic view showing one embodiment of the artificial cornea of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

FIG. 10 is a schematic view of an artificial cornea obtained in Example 1 of the present invention, wherein (a) is a schematic sectional view and (b) is a schematic plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Artificial cornea 2 Optical part 3 Support part 3a Back surface 4 Flange part 5 Through-hole

Claims (3)

[Claims] 1. An optical unit comprising an optically transparent material,
A support portion having a fine gap structure for surrounding and supporting at least a part of the optical portion, and a collar portion covering the rear surface of the support portion and in contact therewith, and protruding outward from the support portion. An artificial cornea, provided with: (1), wherein a through-hole is provided in a collar portion in contact with the support portion and / or a collar portion protruding outside the support portion. 2. The artificial cornea according to claim 1, wherein the through-hole is provided in a collar portion that comes into contact with a support portion. 3. The artificial cornea according to claim 1, wherein the supporting portion has flexibility.