Intracorneal lens with central hole

FIELD: medicine.

SUBSTANCE: invention relates to field of ophthalmology, namely to means of vision correction. Intracorneal lens, intended for implantation in cornea, contains optical part, which has optical axis and through hole, which is coaxial with optical axis, and dimensions and shape of hole are chosen in such a way, that hole does not change optical characteristics of lens, but remains visible for the person, who manipulates the lens.

EFFECT: creation of intracorneal lens, which do not require provision of swelling during their implantation, as well as do not require cutting recess with exact position and dimensions in cornea.

18 cl, 17 dwg

 

The level of technology

The present invention relates generally to intracorneal lenses and to methods of vision correction by introducing intracorneal lens in a patient's eye.

A known method of providing alternatives to glasses and extraocular contact lenses by applying intraocular or intracorneal contact lenses for the correction of violations of visual activity.

Intraocular lens (IOL) is usually introduced into the chamber of the eye, in the capsular bag or between the iris and lens of the eye. Intraocular lenses typically include a Central portion having optical corrective power, and the peripheral supporting portion. Peripheral portion, known as haptic, in General, is provided to help manipulate the lens, and also allows you to hold the lens in position within the eye.

Patent publication US 2004/0085511 A1 (Uno et al.) discloses an intraocular lens designed to enter the rear chamber of the eye. The lens has optical part and the supporting part. When the lens is placed in the eye, the edge supporting part contacting with the outer edges of the rear camera, between the edges of the iris and ciliary body. The supporting part has a size to properly align the optical part with the iris. The optical part is made on the size of the frames so that to the hole in the iris never exceeded the diameter of the optical part. The inner part of the eye, filled with aqueous humor, and lens includes grooves and pores to ensure the flow of aqueous humor within the eye.

PCT/US05/14439 (inventors are the authors of the present invention) discloses an intraocular lens for insertion into the posterior or anterior chamber of the eye. The lens has optical part and the supporting/haptic part. The lens, located in the anterior chamber of the eye, held in place in the eye by interaction haptic part with iridocorneal corner of the eye. Lens located in the rear chamber of the eye, held in place in the eye by interaction haptic part with the angle between the iris and the ciliary body of the eye. Lenses include grooves and pores for passage of aqueous humor within the eye. In addition, the haptic portion of the lens includes an orientation mark. Lenses can be inserted into the eye in a folded configuration and the unfolded in the eye. Orientation marks help the surgeon to determine the position of the front and rear surfaces of the lenses.

Intracorneal lenses differ in several aspects from intraocular lenses. Intracorneal lenses are inserted into the cornea, and not inside the chambers of the eye. Because intracorneal lenses are designed for insertion within the female agovice, they are less intraocular lenses. As intracorneal lenses and intraocular lenses have different position in relation to the lens of the eye, intracorneal lenses and intraocular lenses to have different optical properties for correction of the same anomalies of the eye.

Figure 1 shows the cross section of the eye with the cornea 2. Developed many devices for the preparation of the cut in the cornea of eyes with visual impairment. Then intracorneal the lens is inserted and supported in the neck of the cornea, for example, as shown in figure 2. Figure 2 shows intracorneal lens 4 in the neck 6 of the cornea 2 of the eye.

As detailed above, the intraocular lens has a supporting part that interacts with the natural edges of the chambers of the eye to align the lens inside the eye. However intracorneal lens is inserted into an artificial cut in the cornea, with no natural edges, which can interact lens for alignment in the eye.

However, in General it is necessary to precisely align intracorneal the lens from the predetermined axis of the eye to obtain the necessary correction of abnormalities of the eye.

PCT 2001 US 25376 (Feingold) describes a device for cutting the cornea pocket, accurately located and measured, and intracorneal lenses intended for insertion in such Armani. In the preferred embodiment the pocket is essentially round with a hole lateral access, smaller than the diameter of the pocket. Lenses have a smaller diameter than the diameter of the pocket out of the cornea, and swell up to a diameter of the pocket in the cornea. This helps to hold the lens in aligned position in the cornea.

However, not all intracorneal lenses can swell when injected into the cornea. In addition, the cutting of the pocket with the exact position and size can be difficult and/or time-consuming.

Accordingly, a device or a way to implant intracorneal the lens without the necessity to use lenses designed for swelling in the introduction to the cornea, or without having to cut the pocket with the exact position and size in the cornea.

Disclosure of inventions

The present invention satisfies the above needs by providing a lens with a Central hole, with a size small enough to avoid breaking the optical properties of the lens, and large enough so that the surgeon could see the hole and align it with the mark indicating the axis of the eye during implantation of the lens into the cornea.

In particular, the present invention provides a lens for implantation in the cornea, which contains an optical portion having an optical axis and Squaw is a great hole in the lens; when this hole is coaxial with the optical axis, and the size and shape of the holes is selected so that the hole had not violated the optical properties of the lens and remained visible for someone who manipulates the lens.

In accordance with a variant embodiment of the invention, the hole has a diameter of from 50 to 500 microns.

In accordance with a variant embodiment of the invention, the optical axis of the lens passes through the center of the lens.

In accordance with a variant embodiment of the invention, the hole has a diameter greater than 100 micrometers.

In accordance with a variant embodiment of the invention, the hole has a diameter of less than 200 micrometers.

In accordance with a variant embodiment of the invention, the lens includes at least one round non-optical part having no optical power and which is concentric with the hole.

In accordance with a variant embodiment of the invention, a non-optical portion surrounded by the optical part.

In accordance with a variant embodiment of the invention, the hole is the only hole.

In accordance with a variant embodiment of the invention, the hole diameter varies along the depth of the hole.

In accordance with a variant embodiment of the invention, the first part of the walls of the hole corresponds to the first part of the cone, the diameter of the hole decreases from the first outer diameter, at the entrance from which Erste, to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the hole corresponds to the second part of the cone, increasing from the inner diameter to the second outer diameter at the other entrance of the hole.

In accordance with a variant embodiment of the invention, the first part of the walls of the hole corresponds to the first part of the centre of the torus, while the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the hole corresponds to the second part of the Torah, increasing from the inner diameter to the second outer diameter at the other entrance of the hole.

In accordance with a variant embodiment of the invention, the first part of the walls of the hole corresponds to the part of the cone, and the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the holes corresponds to the part of the Torah, increasing from the inner diameter to the second outer diameter at the other entrance of the hole.

In accordance with a variant embodiment of the invention, the third part of the walls of the hole, mizuiro and second parts of the walls of the hole, corresponds to a cylinder having a diameter equal to the inner diameter.

In accordance with a variant embodiment of the invention, the wall of the hole correspond to the cone from one of the entrance holes to the other entrance to the hole.

In accordance with a variant embodiment of the invention, the wall of the hole correspond to the cylinder from one of the entrance holes to the other input of the hole.

In accordance with a variant embodiment of the invention, the front and back surfaces of the lenses contain at least a portion of one of the following types of surfaces: spherical surface with a single focus, spherical surface with two or more foci, a non-spherical surface with progressive focal area, a toric surface and a flat surface.

In accordance with a variant embodiment of the invention, the front and/or rear surface includes a stepped part.

Another object of the present invention relates to a method of correction of the optical properties of the cornea along a given axis of the eye. The method includes:

drawing marks on the cornea of the eye at the intersection of the surface of the cornea with a given axis;

the creation of the corneal thickness of the cut made with the possibility of receiving lenses near a given axis, the dimensions of the cutout in order to adjust the position of the lens in the neck;

the introduction of the lens, is accomplished according to any one of items 1-17, in the neck; and

the alignment holes of the lens with the mark on the cornea.

Brief description of drawings

Figure 1 - cross section of the eye.

Figure 2 - cross section of the anterior chamber having intracorneal the lens inside the eye cornea.

Figure 3 - cross section of a corneal pocket for receiving intracorneal lenses.

Figa - enlarged image lens according to a variant of embodiment of the present invention.

Figw - lens figa in cross section.

Figs depicts a closeup of the center figv.

Fig.4D depicts the area of the hole from the private choices of the incarnation.

Figa illustrates a method in accordance with the present invention.

FIGU is a top view of an eye having a cornea with intracorneal lens in accordance with the present invention.

Figs the cornea of figv in cross section.

Fig.5D - another view of the cornea of figv in cross section.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv depicted Rupnik plan.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs center with figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs - edge figv shown.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section.

Figs - edge figv shown.

Fig illustrates how l the Chi of light pass through the lens to figa-C.

Fig illustrates how light rays pass through a different lens on figa-C.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section; illustration of the passage of light rays through the lens.

Figa - magnified image of the lens in accordance with another alternative embodiment of the present invention.

Figw - lens figa in cross section; illustration of the passage of light rays through the lens in cross section.

Figs - lens figa in the second cross section; illustration of the passage of light rays through the lens in cross section.

The implementation of the invention

The present invention is a means for a permanent, albeit reversible, correction of visual defects by placing the lens in a pocket in the cornea. Different ways embodiment provides correction of myopia, hypermetropia, astigmatism, presbyopia or a combination of these defects. You should understand that the present invention is not limited to the treatment of these defects and the treatment of other conditions of the eye is also within the scope of the invention. Correction can be permanent, if there is satisfactory, and can also be reversible when removing the lens from the cornea.

Lenses in accordance with this the image is the group of intended for example, for introduction into the pocket of the cornea is performed using a device for corneal pockets Keratome, disclosed in PCT 2001 US 25376 (Feingold). As described further pocket in the cornea may be slightly longer lens, leaving space for adjusting the position of the lens inside pocket.

Figure 3 shows the cornea 2 in cross section, in which is cut a pocket or neck 6. The access hole 8 provides input into the groove 6.

Figa shows the refractive lens 40 in accordance with a variant embodiment of the present invention. As detailed hereinafter, the lens 40 is intended for insertion into the neck of the cornea as shown in figure 3. The lens 40 is a spherical lens in which both internal and external surfaces are portions of a sphere, as shown figv. The lens 40 has one optical part 42 having optical power. The optical part 42 has an optical axis 44. As detailed below, in some embodiments, embodiments of the invention, the lens may contain a non-optical portion, coaxial with axis 44 or not, inside or around the optical part. The lens may have a diameter of from 1.5 to 6 μm.

The lens 42 additionally has a hole 46, coaxial with the optical axis 44 of the lens and passing through the lens 40. In accordance with the invention, the size and shape of the holes is selected so that the hole had not violated the optical with the properties of lenses and remained visible for who manipulates the lens. The hole preferably has a diameter of from 50 to 500 μm. More preferably, the hole has a diameter of from 100 to 200 μm. More preferably, the hole has a diameter of 150 μm. The inventors have found that, surprisingly, the hole with the preferred size does not violate the optical properties of the lens (not noted by the patient), and at the same time remains visible for the surgeon manipulates the lens. This discovery was made intuitively, because we believed that the hole is large enough to be visible to the surgeon, will be so large that impairs the optical properties of the lens, for example, due to indentirovaniya regional Shine from the edge of the hole. However, this was not observed in the case of the preferred size of the hole. In the present invention it is believed that if the hole does not cause significant luster, which can be checked by the user wearing the lens in the eye, the hole does not violate the optical properties of the lens.

As shown in figs, the wall of the hole may correspond to a cylinder from one of the entrance holes to the other input of the holes. To reduce Shine, induced by the hole, the size and shape of the holes are pre chosen so as to minimize the area of surface reflection of the hole. Fig.4D shows, for example, that when the thickness of the Lin is s about 0.03 mm holes and the hole, having a diameter of 150 micrometers, the surface area of the holes is of 0.014 mm2. The thickness of the lens around the holes can be from 0.07 mm to 0.005 mm, the Inventors have found that such a surface area of the hole does not cause a sheen, which can be checked by the user wearing the lens in the eye.

As described in detail hereinafter, the wall of the hole may also vary from a simple cylinder to further reduce the surface reflection of the hole.

The lens corresponding to the present invention, allows to apply the correction method of the optical properties of the cornea along a predefined axis of the eye in accordance with a variant embodiment of the invention. This way, for example, illustrated in figa.

In step 1 put a label on the cornea of the eye at the intersection of the surface of the cornea with a pre-specified axis along which you want to adjust the optical properties of the cornea. Marking can be performed on the outer surface of the cornea with a laser, cutting and/or piercing device, by applying pigmentation or temporary prokalivaniem or adhesion of the marking device to the surface of the cornea.

At stage 2 in the thickness of the cornea to create a cutout for receiving lenses, such as cut, shown in figure 3. The neckline can be created by keratoma pocket horn is vitsy, as described in PCT 2001 US 25376; or with a laser. The laser can be guided by computer control, as is well known in the art. The hole in the cornea can be formed by methods similar to those used during procedures LASIK (laser-assisted in situ Keratomileusis). Alternatively, a pocket in the cornea can be formed using laser and pattern, giving the shape of the pocket, as described in PCT 2007 US 63568 (Feingold). Alternatively, a pocket in the cornea may be formed by the surgeon manually using portable instruments.

The valve of the cornea (not shown) may be formed alternatively the hole in the cornea.

The sizes of the slot should be such that you can position the lens to fit in the cutout. The depth is cut under the outer surface of the cornea, choose from depending on how much you need to adjust optical properties of the cornea, the type of lenses, etc. the Order of stages 1 and 2 can be changed if necessary.

Phase 3 cutout insert the lens corresponding to the invention, with an optical part having an optical axis and an aperture in the lens, and the hole is concentric with the optical axis, and the size and shape of the holes is selected so that the hole had not violated the optical properties of the lens, but Otavalo is visible for who manipulates the lens. The lens is designed to correct the optical properties of the cornea with the introduction of the neckline and the alignment axis of the lens with a predefined axis of the eye. Lens and neckline are such that the centering hole on the mark on the cornea aligns the axis of the lens along a predefined axis of the eye. The fluid may be introduced into the cutout to facilitate the introduction of the lens. To move the lens to the desired position can be used cannula or a small spatula.

Next, in step 4 align the hole of the lens on the mark on the cornea. The hole dimensions of the lens are such that the hole is still visible for those who manipulates the lens of the cornea above the neckline, where the lens. The inventors have noted that if the hole diameter is too large, it can be difficult to accurately align the hole on the mark on the cornea. For example, this may be due to the fact that the edges of the holes are too far from the mark, to know, are they removed from the mark. Also for this reason, the diameter of the hole preferably has the dimensions described above.

The cut in the cornea sealed itself, and after a few days the epithelium covers the entrance to the neckline.

On FIGU shows a top view of the eye 50, with the cornea 52 with intracorneal lens 54 in the accordance with the present invention, the neck 56 of the cornea.

Figs - view of the cornea with pigv in cross-section in the plane C-C, including a predefined axis 58 of the eye; and fig.5D - view of the cornea with pigv in cross-section in the plane D-D, also includes a predefined axis 58 of the eye and perpendicular to the plane C-C. a predefined axis of the eye can be centered or not centered with respect to the cornea, depending on the anomaly that should be corrected.

It is known that cells of the cornea receives nutrients by diffusion of tear fluid on the outer surface and watery moisture on the inner surface, as well as the neurotrophins supplied by nerve fibers that Innervate it. Oxygen is delivered from the air. It is known for manufacturing intracorneal lenses from a biocompatible material that provides a sufficient diffusion of gas for adequate oxygenation of the tissues of the eye (such materials include silicone, hydrogels, urethanes or acrylics). However, the inventors noted that when intracorneal lens implanted in the cornea, the holes in the lens of the present invention, as it seems, enhances the transport of nutrients within the cornea, which is favourable for the cornea and, for example, facilitates the healing of the cornea after implantation of the lens. In addition, the image is ateli said, when software flow through the opening in the cornea is not observed turbidity or opacity after the healing period.

Preferably, the hole in the lens passes through the center of the lens. The inventors noted, in particular, that when the lens has a dome shape with a concave surface and a convex surface, the location of the hole in the center of the lens, as it seems, and also increases the transport of nutrients within the cornea, which is more favourable to the cornea.

Figa shows the lens 60, corresponding to another variant embodiment of the present invention. The lens 60 is a spherical lens in which both internal and external surfaces are portions of a sphere, as illustrated in figv. Lens 60 includes a circular optical portion 62 with an optical axis 64 and the hole 66, coaxial with the axis 64. Lens 60 also includes all non-optical portion 68 that do not have optical power inside the optical unit 62 and is concentric with the optical part 62.

In some embodiments, embodiments of the invention the position of the optical part (such as an optical part 62 on figa) and non-optical parts (such as non-optical portion 68 on figa) can be interchanged.

Some other variants of embodiments of the invention may include a number of concentric optical and non-optical parts, cerebus is camping in any way (1-1, 1-2, 2-1, etc).

In some other embodiments, embodiments of the invention non-optical part can be concentrical with the axis of the optical part.

As shown in figs, the wall of the hole may correspond to a cylinder from one of the entrance holes to the other entrance to the hole. However, as described in detail below, the wall of the hole may also have a different shape to reduce the risk of creating a Shine on the walls of the hole.

Figa shows the lens 70 in accordance with another alternative embodiment of the present invention. The lens 70 is a spherical lens in which both internal and external surfaces are portions of a sphere, as illustrated in figv. Lens 70 includes a circular optical portion 72 with an optical axis 74 and the hole 76, coaxially with the axis 74. Lens 70 also includes all non-optical portion 78 that does not have optical power inside the optical unit 72 and is concentric with the optical part 72.

As shown in figs, the diameter of the hole 76 is changed according to the depth of the hole. The first part of the walls of the hole corresponds to the first part of the Torah: the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes. The second part of the walls of the hole corresponds to the second part of the Torah, felicias from the inner diameter to the second outer diameter, at the other entrance holes. The radius of curvature of the circle of the torus can be from 0.01 mm to 0.002 mm, the Third part of the walls of the hole, between the first and second parts of the walls of the hole is cylindrical and has a diameter equal to the inner diameter. On figs first and second outer diameters shown are equal. However, they may also vary.

The lens shown in figa-C is spherical. However, as detailed below, the lens in accordance with the present invention may also be aspheric.

Figa shows the lens 80, corresponding to another variant embodiment of the present invention. Lens 80 is a spherical lens in which both the internal and external surface are portions of a sphere, as illustrated in figv. Lens 80 includes a circular optical portion 82 with an optical axis 84 and the hole 86, coaxially with the axis 84. Lens 80 also includes all non-optical portion 88 that does not have optical power inside the optical unit 82, and located concentric with the optical part 82.

As shown in figs, the hole diameter varies along the depth of the hole. The first part of the walls of the hole corresponds to the first part of the Torah: the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, an intermediate position is inside the hole. The second part of the walls of the hole corresponds to the second part of the Torah, increasing from the inner diameter to the second outer diameter at the other entrance holes. The radius of curvature of the circle of the torus may be from 0.025 mm to 0.0025 mm pigs first and second outer diameters shown are equal. However, they may also vary.

Figa shows the lens 90, corresponding to another variant embodiment of the present invention. The lens 90 is a spherical lens in which both internal and external surface are portions of a sphere, as illustrated in figv. Lens 90 includes a circular optical portion 92 with an optical axis 94 and the hole 96, coaxial with the axis 94. Lens 90 also includes all non-optical portion 98 that do not have optical power inside the optical part 92 and is concentric with the optical part 92.

As shown in figs, the hole diameter varies along the depth of the hole. The first part of the walls of the hole corresponds to the part of the cone, the diameter of the hole decreases from the first outer diameter, at the entrance hole on the front surface of the lens to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes. The second part of the walls of the hole corresponds to the part of the Torah, increasing from the inner diameter to the second outer diameter at the outer entrance of the CTE is participation on the rear surface of the lens. Part of the cone, which correspond to the wall of the hole may refer to the cone formed by rotating a triangle with an angle of 10-30 degrees around the axis of the hole.

Figa shows the lens 100 in accordance with another alternative embodiment of the present invention. The lens 100 is a spherical lens in which both internal and external surfaces are portions of a sphere, as illustrated in figv. The lens 100 includes a circular optical portion 102 with the optical axis 104 and the hole 106, coaxially with the axis 104. Lens 100 also includes all non-optical portion 108 that do not have optical power inside the optical unit 102 and located concentric with the optical part 102.

As shown in figs, the hole diameter varies along the depth of the hole. The first part of the walls of the hole corresponds to the part of the cone, and the diameter of the hole decreases from the first outer diameter of the inlet holes on the rear of the lens surface to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes. The second part of the walls corresponds to the part of the Torah, increasing from the inner diameter to the second outer diameter at the outer entrance hole on the front surface of the lens.

Figa shows the lens 110 in accordance with another variant embodiment of the invention. The lens 110 is the fast spherical lens, in which the inner and outer surface are portions of a sphere, as illustrated in figv. The lens 110 includes a circular optical portion 112 with an optical axis 114 and the hole 116, coaxially with the axis 114. The lens 110 also includes all non-optical portion 118 that do not have optical power inside the optical part 112, and is concentric with the optical part 112.

As shown in figs, the hole diameter varies along the depth of the hole. The first part of the walls of the hole corresponds to the first part of the cone, the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter in an intermediate position within the holes. The second part of the walls of the hole corresponds to the second part of the cone, increasing from the inner diameter to the second outer diameter at the other entrance holes. On figs first and second outer diameters shown are equal. However, they may also vary.

In accordance with a variant embodiment (not shown), the wall of the hole may correspond to a cone from one of the entrance holes to the other entrance to the hole.

Lens shown in figa-C and 6A-C, 11A-C, are all refractive spherical lenses, which have both internal and external surfaces are parts of spheres. However, the present invention is not limited the tsya such lenses. For example, the lenses in accordance with the present invention can be diffractive lenses, such as multi-lenses, and include an annular series of sections of the lens between the outer edge of the lens and the Central part of the lens. A wider range and regulation of refraction provided by the multi-stage lens, particularly useful for the correction of presbyopia by means of the method and device according to the present invention.

Annular ridges multistage lenses resistant to lateral displacement, but a multi-stage lens may also have properties hold. Multi lenses may have an outer surface (front or back), which is part of the sphere, while the other outer surface includes a series of annular sections of the lenses smaller and smaller.

Figa shows a multistage lens 120 with a reduced thickness in accordance with a variant embodiment of the present invention. The outer surface of the lens 120 is part of the sphere, as illustrated in figv. The lens 120 includes a circular optical portion 122 with an optical axis 124 and the hole 126, coaxially with the axis 124. Lens 120 also includes all non-optical portion 128 that do not have optical power inside the optical unit 122, and is concentric with the optical part 122. As shown in detail figs, the optical portion 122 which incorporates both a series of concentric circular rings 1220, 1222, 1224, 1226, etc. formed on the inner surface of the lens in a stepwise manner. In the variant embodiment shown in figs, each of the concentric rings 1220, 1222, 1224, 1226, etc. corresponds to a plane perpendicular to the axis 124. Further, concentric rings 1220, 1222, 1224, 1226, etc. are connected with one another by walls 1221, 1223, 1225, 1227, and so on, with each ring corresponds to a cylinder having the same axis as the lens. The connection between the rings 1220, 1222, 1224, 1226, etc. and cylindrical walls 1221, 1223, 1225, 1227, etc. can be rounded. The outer edges of the lenses 120 can, for example, be beveled to correspond to the part of the cone 1201 coaxially with the axis 124.

The shape of the opening 126 is not shown in figa-C. However, the hole in the lens in accordance with the present invention may have any shape, as shown in the previous figures, or any other suitable shape.

The number and size of rings 1220, 1222, 1224, 1226, etc. shown in figa-C, is only an example. Can be used any number and size of rings. Further, each ring shows the corresponding parallel plane, but if necessary, each ring or some of the rings may correspond to a plane that is not parallel to other planes, or part of a cone, sphere, torus, elliptic, parabolic or hyperbolic surface or of a polyhedron (with flat the e or not a flat surface).

In addition, the rings 1220, 1222, 1224, 1226, etc. shown round and concentric, but if necessary, they can have different shapes, for example elliptical, or have different centers.

Figa shows a multistage lens 130 with a reduced thickness in accordance with another alternative embodiment of the present invention. The outer surface of the lens 130 is part of the sphere, as illustrated in figv. The lens 130 includes a circular optical portion 132 with an optical axis 134 and hole 136, coaxially with the axis 134. The lens 130 also includes all non-optical portion 138 that do not have optical power inside the optical unit 132, and is concentric with the optical part 132. As shown in detail figs, the optical unit 132 includes a series of concentric conical parts, decreasing the size 1322, 1324, 1326, etc. formed on the inner surface of the lens in a stepwise manner and having the same axis - the axis 14 of the lens. In the embodiments shown in figs, part of the cones 1322, 1324, 1326, etc. are connected to one another by walls 1323, 1325, 1327, etc. with each corresponds to a cylinder having the same axis as the lens. Connections between parts of the cones 1322, 1324, 1326, etc. and cylindrical walls 1323, 1325, 1327, etc. can be rounded. On figs flat ring 1320 connects the edge of the lens and the outer edge of the cone of 1322. Outside the edge of the lens 130 may, for example, to be beveled to match the part of the cone 1301, coaxially with the axis 134.

In accordance with some variations of the embodiment of the invention, parts of the cones can alternatively be parts of spheres or parts of the torus, elliptical, parabolic, or hyperbolic surfaces. Alternatively, each part of the cone may be replaced by a series of parts of a cone having different angles. The number and size of cones, shown in the figures, given only as an example. Can be any suitable number and size.

Figa-C and 13A-C show a lens having an outer surface forming part of a sphere, and a stepped rear surface. However, the lens in accordance with the present invention can alternatively be back surface, which is the part of the sphere, and a stepped front surface. Lens in accordance with the present invention can be also an alternative to have a stepped front and rear surfaces.

Lens in accordance with the present invention may have a single focal length. Such lenses are generally sufficient for the correction of simple myopia or hypermetropia.

Fig illustrates how light rays 140 pass through the upper part of the cross-section of the lens 120 as shown in figa-C in variants of the embodiment, where the lens is a lens with a single the single focal point 142.

However, lenses with variations of the refractive index or shape of the lens, or both, can preferably be used as part of the present invention to install a multi-focus lenses. Focal length of such lenses is not constant, but varies over the lens. This mnogopotochnost lenses can be used to compensate for presbyopia, helping to focus one part of the world, part of the eye, if the light source is removed, while another part of the light is focused when the source is close (as in reading). The effectiveness of such lenses with variable focal length depends on reliable positioning to avoid disrupting the alignment of the lens and to facilitate adaptation to multiple focal distances of visual processing. For example, presbyopia can be compensated by the location of the lens reduces the focal length, with a small area, for example with a diameter of less than 3 mm, in the center of the cornea. This location will have a greater effect in conditions of high illumination (typical read), when the pupil is narrow, and the proportion will have less effect in low light conditions such as night driving, when the pupil is wide. Thus, the location of the lens relative to the pupil will retain the Xia; and the brain adapts more quickly to non-uniform focus of the eye, which is at least constant.

Fig illustrates how light rays 150 pass through the upper part of the cross-section of the lens 120, such as shown in figa-C in variants of the embodiment, where the lens is a lens that has three focal points 152, 154 and 156.

In accordance with a variant embodiment of the invention, mnogopotochnost can also be carried out using a multi-stage lens having non-spherical surfaces.

Figa shows an enlarged image nemegosenda lens having non-spherical surfaces. The cross-section of the upper part of such a lens is shown in figv. The lens 160 of figa-B includes a Central non-spherical dome portion 162 that defines a first focal zone 164 wills axis 165 of the lens. The Central portion 162 is surrounded by a peripheral non-spherical annular part 166 defining a second focal zone 167 along the axis 166 of the lens. The hole 168 in accordance with the present invention passes through the center of the lens. Non-spherical surface may be such that the cross-section surface along the axis of the lens corresponds to a part of an ellipse, parabola or hyperbola.

In accordance with a variant embodiment of the invention, changing the focal length of toric surfaces can be applied to DL the correction of astigmatism. Lenses in accordance with the present invention may be multi-focal lenses, which are simultaneously correct or compensate for various combinations of defects, including myopia, hyperopia, astigmatism and presbyopia.

Figa shows such a lens 170 in accordance with the present invention. Front outer surface of lens 170 corresponds to the complex toric surfaces. The lens 170 includes a circular optical portion 172 with the optical axis of the hole 174 and 176, coaxially with the axis 174. The lens 170 also includes all non-optical portion 178 that do not have optical power inside the optical unit 172, and is concentric with the optical part 172.

Figv shows a half cross-section of the lens 170 along the plane A-A parallel to the axis 174, shown in figa. Figv shows a half cross-section of the lens 170 along the plane C-C parallel to the axis 174, shown in figa.

The outer surface of lens 170 corresponds to the first toric surface along the plane a-a and a second toric surface along the plane C-C.

As shown in detail figv, the optical part 172 includes a series of concentric circular rings formed on the inner surface of the lens in a stepwise manner, for example, therefore, as in the variant embodiment shown in figa-C.

As shown in figv, which is also illustrated, as light rays pass through the lens, the first toric surface works in conjunction with stepped inner surface of the lens so that the lens 170 has a first focal point 1701 on the plane A-A. on the other hand, as illustrated in figs, the second toric surface works in conjunction with stepped inner surface of the lens so that the lens 170 has a second focal point 1702 on the plane C-C.

In accordance with the present invention, the lenses may be formed from a biocompatible material that provides a sufficient diffusion of gas for sufficient oxygenation of the tissues of the eye (such materials may include silicone, hydrogels, urethanes or acrylics). Materials that can be used in the formation of intraocular lenses generally known in the art, as disclosed, for example, in the patent document US 5217491. Preferably the lens in accordance with the present invention are deformable.

It should be understood that the foregoing relates to exemplary variation of the embodiment of the invention, and can be made of modification without departure from the scope of the following claims.

For example, the front and back surfaces of the lens in accordance with the present invention can have at least part of any of the following types of surfaces: spherical is the only focus. spherical with two or more foci; non-spherical with progressive focal area; toric, aspheric and flat. Further, each of the front and back surfaces of the lens in accordance with the present invention may be smooth or stepped.

The radius of curvature of the anterior and posterior surfaces of the lens part according to the variant embodiment of the invention may be the same or may differ. In addition, the surface of the lens part may have multiple radii of curvature along the perimeter section that will allow you to compensate for the spherical aberration of the cornea.

In addition, a variant of the embodiment of the present invention may include intracorneal lens having an optical portion, as described above; and a haptic portion, surrounding the specified optical part, where the haptic portion is corrugated. Intraocular lens may include internal dome part and the outer part, with many petals located on the periphery of the outer part, where the dome part passes axially from many petals. The embodiment of the present invention may also include intracorneal lens having a Central optical portion and the outer haptic portion, where the haptic part comprises an annular part located adjacent and directed radially outward from the optical the Asti; a pair of inner arcuate furrows adjacent to the annular part and directed radially outward from it, a pair of inner arcuate grooves located on opposite sides of the optical part; and a pair of outer arcuate furrows adjacent pair of inner arcuate furrows and directed radially outward from them. Haptic element may include at least one irrigation channel, radially located within the specified haptic element. Arcuate grooves of a pair of furrows can be concentric.

Lenses described above, contain a hole. However, variants of the embodiment of the present invention may include additional holes in other parts of the lens. Additional holes can be provided for transport of nutrients, but not for alignment of the lens, and can have a diameter less than the diameter of the center hole. This makes the peripheral holes too small to be visible to the one who manipulates the lens, but allows you not to disturb the optical properties of the lens.

The invention is not limited to the embodiments described above but is defined by the following claims.

1. Lens for implantation in the cornea, which contains an optical portion having an optical axis and through which twistie in the lens, and the hole is coaxial with the optical axis, and the size and shape of the holes is selected so that the hole had not violated the optical properties of the lens, but remained visible for someone who manipulates the lens.

2. The lens according to claim 1, in which the hole has a diameter of from 50 to 500 microns.

3. The lens according to claim 1 or 2, in which the optical axis of the lens passes through the center of the lens.

4. The lens according to claim 1, in which the hole has a diameter greater than 100 microns.

5. The lens according to claim 1, in which the hole has a diameter less than 200 microns.

6. The lens according to claim 1, in which the lens has at least one round non-optical part, do not have optical power and is concentric with the hole.

7. The lens according to claim 6, in which the non-optical portion surrounded by the optical part.

8. The lens according to claim 1, in which the opening is a single opening.

9. The lens according to claim 1, in which the hole diameter varies along the depth of the hole.

10. The lens according to claim 9, in which the first part of the walls of the hole corresponds to the first part of the cone, and the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the hole corresponds to the second part of the cone, increasing from the specified internal diameter to the second outer diameter D. the ugogo the entrance hole.

11. The lens according to claim 9, in which the first part of the walls of the hole corresponds to the first part of the Torah, and the hole diameter decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the hole corresponds to the second part of the Torah, increasing from the specified inner diameter to a second outer diameter at the other entrance of the hole.

12. The lens according to claim 9, in which the first part of the walls of the hole corresponds to the part of the cone, and the diameter of the hole decreases from the first outer diameter at the entrance of the hole to an inside diameter smaller than the first outer diameter, at an intermediate position within the holes, and the second part of the walls of the hole corresponds to the part of the Torah, increasing from the specified inner diameter to a second outer diameter at the other entrance of the hole.

13. Lens according to any one of p-12, in which the third part of the walls of the hole, between the first and second parts of the walls of the hole corresponds to a cylinder having a diameter equal to the inner diameter.

14. The lens according to claim 9, in which the wall of the hole correspond to the cone from one of the entrance holes to the other entrance to the hole.

15. The lens of claim 8, in which the wall of the hole correspond to cilin the Roux from one of the entrance holes to the other entrance to the hole.

16. The lens according to claim 1, in which the front and back surfaces of the lenses contain at least a portion of one of the following types of surfaces: spherical surface with a single focus, spherical surface with two or more foci, a non-spherical surface with progressive focal area, a toric surface and a flat surface.

17. The lens according to claim 1, in which the front and/or rear surface includes a stepped part.

18. The correction method of the optical properties of the cornea along a given axis of the eye, characterized by the fact that put a mark on the cornea of the eye at the intersection of the surface of the cornea with a given axis; perform in the thickness of the cornea is cut to receive the lens close to a given axis, the dimensions of the cutout in order to adjust the position of the lens in the neck; insert the lens according to any one of claims 1 to 17 in the neck and align the hole of the lens with the mark on the cornea.



 

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25 cl, 7 dwg

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5 cl, 4 tbl

FIELD: ophthalmology.

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12 cl, 1 dwg.

FIELD: ophthalmology.

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9 cl, 2 dwg.

FIELD: physics.

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7 cl, 9 dwg

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12 cl, 4 dwg

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11 cl, 7 dwg

FIELD: physics.

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34 cl, 44 dwg

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7 cl, 2 tbl

FIELD: medicine.

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18 cl, 22 dwg

FIELD: medicine.

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19 cl, 4 tbl, 2 dwg, 2 ex

FIELD: medicine.

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19 cl, 4 tbl, 10 ex

FIELD: physics.

SUBSTANCE: one version of the invention provides a diffraction ophthalmic lens which can be, for example, an intraocular lens which includes an optical element having a front surface and a rear surface, where the optical element provides a long focus. The broken diffraction structure containing a collection of diffraction zones lies on at least one of said surfaces to provide near focus. Each zone is separated from the neighbouring zone by the boundary of a zone which causes optical delay in the incident light. Also, at least two successive boundaries of the zone have such a configuration where the difference between their corresponding phase delays for at least one wavelength of incident light is greater than approximately ¼ of the wavelength for directing part of the incident light to the position between the near and far foci.

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36 cl, 8 dwg

FIELD: physics.

SUBSTANCE: according to one version of the invention, the intraocular lens includes a rear optical element and a front optical element. One optical element provides compensation for radial-symmetrical aberration and the other provides compensation for radial-asymmetrical aberration.

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27 cl, 4 dwg

FIELD: physics.

SUBSTANCE: multi-focus lens has an optical element, having a surface which has at least one bifocal diffraction structure and one trifocal diffraction structure. The bifocal diffraction structure is configured to provide near and far sight and the trifocal diffraction structure is configured to provide near, far and intermediate sight.

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24 cl, 8 dwg

FIELD: medicine.

SUBSTANCE: multifocus ophthalmologic lens contains an optic element having at least one optic surface and a set of diffraction regions surrounding an optical axis of the optic element, at least two variable diffraction regions. According to the invention, external and internal diffraction regions direct the incident light energy to near and far focuses respectively to enable in common resulting near, intermediate and far focuses; the incident light energy directed to each resulting near and far focuses exceeds a fraction of the incident light energy directed to the intermediate focus.

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21 cl, 8 dwg

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to ophthalmology, and can be used in intraocular correction of planar-haptic intraocular lens (IOL) aphakia in phacoemulsification of cataract complicated by rupture of the posterior capsule of crystalline lens. The method provides partially endo- and partially supracapular lens fixation at the diametrical edges of circular capsulorhexis by clippling them in graduated slots formed in haptic elements of the IOL and created at surgery from each lateral edge of each haptic element in its proximal portion. The slots are represented by four rays symmetrical with respect to a central longitudinal axis of the IOL and directed to the centre of an optical portion of the lens. The slot length is graduated considering the anterior continuous circular (ACC) diametre, while the IOL is fixed in such a manner that a part of the proximal ends of the haptic and optical portion of the lens are arranged on the anterior capsule of the crystalline lens.

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2 dwg

FIELD: medicine.

SUBSTANCE: invention refers to ophthalmosurgery. An intraocular lens of gradually varied lens power comprises an optical portion of varied geometry and a bearing portion. The optical portion is composed of at least layer-by-layer separate curved optical elements with their optical axes being matched and passing through the centre of the optical part with various radiuses of curvature, various thicknesses, circumferentially coupled together. Two uniform diametral bow-shaped crescent notches spaced 0.1-0.15 mm from an attachment point are provided at the periphery of each optical element. One of the arches forming a notch is matched with a circle concentric to the optical part, along the arches of the same circle, between the notches, from both sides from the notches, through perforations are formed with the optical elements consecutively layer-by-layer moving off thereon starting with a front surface, the notches in each following of the layer-by-layer optical elements are made with angular displacement relatively to the previous one.

EFFECT: extended range of lens power variation and higher accuracy of its graduation.

4 dwg

FIELD: medicine.

SUBSTANCE: invention relates to ophthalmosurgery. Artificial crystalline lens of eye contains optic and support elements. Anterior surface of optic element is made in form of flat surface. On flat plane periphery segments of toric surface convex in the direction of cornea are located. Posterior surface of optic element is made in form of concave with respect to anterior surface curved surfaces with continuous curvature, having one central axis. Central surface is made in form of segment of concave elliptic surface. Ratio of large axis of elliptic surface to optic element diametre lies in the interval from 0.25 to 0.5. Second part of posterior surface is made in form of segment of concave hyperbolic surface. Ratio of segment of hyperbolic surface to diametre of optic element lies in interval from 0.35 to 0.45. Peripheral part of posterior surface is made in form of segment of parabolic surface with ratio of said surface diametre to diametre of optic element lying in the interval from 0.35 to 0.45.

EFFECT: increase of acuity of photopic and scotopic vision to the level of intact eye and reduction of astigmatism.

2 dwg

FIELD: medicine.

SUBSTANCE: method involves carrying out contact correction using lens of +5.0 D during 1 h. Residual eye refraction is determined and focal intraocular lens power from formula Diol=Dcl+Dres+1.0D, where Diol is intraocular lens focal power in diopter; Dcl is the focal power of contact lens in diopters; Dres is the residual eye refraction in diopters; 1.0D is the constant value for minimizing refraction error.

EFFECT: high accuracy in determining focal power of intraocular lens.

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