Corneal shaping contact lenses and related methods

Abstract

The present disclosure provides orthokeratology glasses (201) and methods of making such glasses (201). The orthokeratology glasses (201) disclosed herein comprise: an orthodontic region (206) for reducing the curvature of the central portion of the cornea; an annular treatment groove (208) for inducing myopic defocus in a peripheral portion of the cornea; and an adjustment region (210) for adjusting the myopic defocus induced by the annular treatment groove (208).

Description

Technical Field

[0001] The present disclosure relates to orthokeratology contact lenses and methods. The present disclosure relates particularly (but not exclusively) to contact lenses for reshaping the cornea of ​​the eye to provide optical correction of myopia and slow its progression. The present disclosure also relates to methods for making such lenses. Background Art

[0002] Myopia (also referred to as nearsightedness or shortsightedness) is an eye condition that occurs primarily due to elongation of the eye. An uncorrected myopic eye focuses incoming light from distant objects to a location in front of the retina. Once the light enters the eye, it converges toward a focal plane in front of the retina, after which the light then diverges and becomes out of focus after reaching the retina. The result is that a person with myopia is unable to focus on distant objects.

[0003] Many people use contact lenses to correct myopia. Conventional contact lenses used to correct myopia reduce the convergence of light passing through the contact lens to shift the image plane onto the retina. Hyperopia vision is only improved when the eye+lens power is reduced using contact lenses, glasses, or reshaping the cornea. In addition, while conventional contact lenses correct the mismatch between optical power and eye length, they do not treat the underlying eye size abnormality, which is the basis of myopia.

[0004] Decades ago it was proposed that the progression of myopia in children or young adults could be slowed by undercorrection (i.e., moving the focus toward, but not completely onto, the retina). However, such an approach necessarily results in hyperopic vision that is degraded from the vision obtained with glasses that fully correct myopia. Furthermore, it is now doubted whether undercorrection is effective in controlling myopia progression. A closer approach that can simultaneously provide a focused image at the retina and slow the progression of eye growth is to use glasses with one or more areas of full correction that provide hyperopic vision and one or more areas of undercorrection or intentionally induced myopic defocus. This approach has been shown to slow the development or progression of myopia in children or young adults while providing good hyperopic vision.

[0005] In the case of glasses having a zone that provides a myopic defocus, the zone that provides full correction for distance vision is often referred to as the base power zone and the zone that provides undercorrection is often referred to as the myopic defocus zone or the add power zone (because the refractive power is more positive or less negative than the power of the distance zone). The surface (usually the front surface) of the add power zone has a smaller radius of curvature than the distance power zone and thus provides a more positive or less negative power to the eye. The add power zone is designed to focus light in front of (in front of) the retina while the distance correction optics focus light at or near the retina.

[0006] A known type of contact lens for reducing myopia progression is a bifocal contact lens available under the name MISIGHT (CooperVision Corporation), such as Figure 1. The eyeglass 100 has a central correction zone 101 and two further annular correction zones 102 and 104. The correction zones 101, 102 and 104 are distance power zones that provide a stable correction power or base power across each zone. The eyeglass also has two annular treatment zones 106 and 108. Each treatment zone 106 and 108 is positioned between the two correction zones 101, 102 and 104. The treatment zones 106 and 108 provide added power or myopic defocus. The diameters of the correction zones 101, 102 and 104 and the treatment zones 106 and 108 are well defined and the power provided is stable across each zone. This bifocal eyeglass differs from a bifocal or multifocal contact lens configured to improve vision for a presbyopic person in that the bifocal eyeglass is configured with specific optical dimensions to enable an adaptable person to use distance correction (i.e., base power) to view both distant and near objects. Treatment zones 106 and 108 of the bifocal lens with add-on power are designed to provide myopic defocused images at both far and near viewing distances.

[0007] Although MISIGHT glasses have been shown to correct myopia and slow myopia progression in children (Chamberlain et al., 2019, Optometry and Vision Science , 96(8):556-567; Chamberlain et al. 2022, Optometry and Vision Science , 99(3):204-212), but myopia correction and treatment is only achieved when wearing glasses. An alternative to bifocal contact lenses for providing optical correction of existing myopia while also slowing future progression is orthokeratology. Studies have shown that wearing orthokeratology lenses overnight produces optical correction of myopia (Mounford et al., 2004, Orthokeratology: Principles and Practice (Orthokeratology: principles and practice) , Butterworth-Heinemann Medical) and is also effective in slowing down myopia progression (Cho et al., 2005, Current Eye Research (CurrentEyeResearch) 30(1):71-80). Orthokeratology lenses (often referred to as "ortho-K" lenses) correct myopia by reshaping the corneal surface to modify the curvature of the cornea in defined areas. Thus, orthokeratology lenses impart physical changes to the myopic eye to improve vision.

[0008] Orthokeratology glasses include a central area defined by a rear surface having a low curvature or flat profile designed to flatten the curvature of the cornea. When the glasses are worn, the central correction area applies pressure or compression to the corneal epithelium, which redistributes corneal tissue and / or fluid from the central portion of the cornea to the peripheral portion of the cornea. This redistribution reduces the curvature of the cornea by compressing the cornea at its apex. Because the curvature of the cornea of ​​a myopic person is too steep to focus light on the retina, reducing the corneal curvature shifts the focus of light to the retina and thus corrects myopia to provide improved hyperopia. Examples of orthokeratology glasses are disclosed in U.S. Pat. No. 6,543,897 and U.S. Pat. No. 6,652,095. Although it is disclosed that orthokeratology glasses can correct developed myopia, presbyopia and / or hyperopia, it is not disclosed that such glasses are suitable for treating or slowing down the progression of myopia.

[0009] Orthokeratology lenses gradually reshape the cornea and are therefore usually worn overnight. After several hours of wearing, the cornea will have been reshaped to correct myopia and the user can remove the lenses, for example, in the early morning. After removing the lenses, the cornea retains its new shape for several hours to allow the user to focus on distant objects without corrective lenses. Therefore, orthokeratology lenses offer an advantage over other contact lenses because vision remains corrected even when the lenses are not worn. During the day when the lenses have been removed, the cornea will partially recover its original shape. Therefore, the user must wear orthokeratology lenses every night to maintain the desired shape of the central cornea.

[0010] In addition to the corrective zone, orthokeratology lenses further include an annular arched area (sometimes referred to as a "reverse curve" or "recovery zone") surrounding the central corrective zone of the lens. This area is a groove in the back surface of the lens that accommodates the tissue volume increase of the area of ​​the cornea. The increase in tissue volume of the area of ​​the cornea is caused by redistributing corneal tissue and / or fluid directed from the central corrective zone of the lens to the peripheral portions of the cornea and causes the curvature of the epithelial layer of the cornea to increase. Therefore, the annular arched area allows corneal tissue and / or fluid to move away from the central area of ​​the cornea and thus helps to flatten the central portion of the cornea. The inevitable result of the annular arched area is that the peripheral portions of the cornea to which the fluid and tissue are redistributed will be a single ring of added power or myopic defocus around the central flattened area of ​​the cornea.

[0011] Although orthokeratology lenses have been shown to correct myopia more effectively than MISIGHT-type lenses, the correction zone and the added power zone of the cornea produced by orthokeratology lenses are not clearly defined. The correction provided by the correction zone of orthokeratology lenses is not constant across the central portion of the cornea. It is also challenging to provide a constant added power across the peripheral annular region of the cornea aligned with the annular arch region, and the ring of added power induced in the cornea is generally viewed as an inevitable result of central flattening and not a specific design feature of controlled optics. The limited control of myopic defocus and correction zone induced in the cornea by orthokeratology lenses currently limits their effectiveness in correcting existing myopia and slowing future progression.

[0012] Another problem with orthokeratology glasses is that the diameter of the corrective center portion of the cornea and the amount of added power provided in the peripheral portion of the cornea will vary for different correction amounts. Generally speaking, the greater the amount of myopia, the smaller the diameter of the central corrective portion of the cornea induced by the correction zone of the glasses and the greater the refractive addition provided by the surrounding annular arch area in the peripheral portion of the cornea. This effectively limits the degree of myopia that can be treated by conventional orthokeratology glasses and prevents the level of control that provides a myopia control signal. In contrast, the MISIGHT glasses have a constant central correction zone with a fixed diameter of 3.36 mm and a stable myopia control treatment power regardless of the degree of myopia being treated and well controlled.

[0013] The present disclosure seeks to provide orthokeratology lenses that provide control over the diameter of the corrective center portion of the treated cornea regardless of the level of myopia being treated. Such lenses may further provide a more constant degree of correction across the central area of ​​the cornea. Additionally or alternatively, such lenses may provide a clearly defined area of ​​myopic defocus in the treatment cornea. Summary of the invention

[0014] According to a first aspect, the present disclosure provides a corneal reshaping contact lens for correcting and slowing the progression of myopia, wherein the lens is according to technical solution 1.

[0015] According to the second aspect, the present disclosure further provides a method for manufacturing orthokeratology glasses, wherein the method is according to technical solution 10.

[0016] According to a third aspect, the present disclosure provides a method for manufacturing orthokeratology contact lenses, wherein the method is according to technical solution 11.

[0017] According to a fourth aspect, the present disclosure further provides a method for treating myopia progression, which comprises providing glasses according to the first aspect to a subject in need thereof, wherein the method is according to technical solution 15.

[0018] Optional but preferred features are set out in the dependent claims.

[0019] Of course, it should be understood that features described with respect to one aspect of the present disclosure may be incorporated into other aspects of the present disclosure. For example, a method of preparing a corneal reshaping contact lens according to the present disclosure may incorporate any features described with reference to the corneal reshaping contact lens of the present disclosure and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying schematic drawings, in which:

[0021] Figure 1 is a plan view of a bifocal eyeglass 100 of the prior art;

[0022] Figure 2A is along Figure 2B A cross-sectional view of a pair of glasses 201 according to the present disclosure taken along the axis AA'. The pair of glasses 201 is suitable for treating or slowing down the progression of myopia in a relatively high myopic person;

[0023] Figure 2B yes Figure 2A 201. The limits of each central region correspond to the boundaries of the regions of the eyeglass generally defined by the change in curvature of the rear surface 202 of the eyeglass;

[0024] Figure 3A is along Figure 3B A cross-sectional view of a spectacles 301 according to the present disclosure taken along the axis BB'. The spectacles are suitable for treating or slowing down the progression of myopia in people with relatively low myopia;

[0025] Figure 3B yes Figure 3A 301 shown in FIG. The limits of each central region correspond to the boundaries of the regions of the eyeglass generally defined by the change in curvature of the rear surface 302 of the eyeglass;

[0026] Figure 4A is a cross-sectional view of an eyeglass 401 according to the present disclosure in use. Eyeglass 401 is placed on the surface of cornea 414. For simplicity, the accommodative area of ​​the eyeglass is not shown. Arrows indicate the compressive force applied by the central corrective area 406 of eyeglass 401 on cornea 414 and the resulting flow of fluid and / or tissue from the central portion of cornea 414 to the peripheral portion of cornea 414;

[0027] Figure 4B is a cross-sectional view of the surface profile of the cornea 414 before and after treatment. The dotted line shows the Figure 4ASurface profile of cornea 414 before treatment with spectacles 401. The bold line shows an area of ​​cornea 414 having a modified surface profile after treatment with spectacles 401. The surface profile of cornea 414 after treatment has a flatter and less curved central portion and a lifted and more curved peripheral portion compared to the profile of cornea 414 before treatment;

[0028] Figure 5 yes Figure 4A 401, wherein the regions of the lens 401 are shown (correction region 406, annular treatment groove 408, and fitting region 412). The dimensions (width, curvature, depth, asphericity, and symmetry) of the regions can be adjusted to control the movement of corneal tissue and / or fluid and thus induce a specific profile in the cornea to be treated, which is shown. For simplicity, the accommodation regions of the lens 401 are not shown. Arrows indicate the movement of fluid and / or tissue within the cornea 414;

[0029] Figure 6 yes Figure 4A 401, showing the size of the adjustable annular treatment groove 408. For simplicity, the adjustment area of ​​the eyeglass 401 is not shown. Changes in width of the annular treatment groove 408 are indicated on the left hand side of the eyeglass 401. Changes in tilt or asphericity of the annular treatment groove 408 are indicated on the right hand side of the eyeglass. Arrows indicate movement of fluid and / or tissue within the cornea 414;

[0030] Figure 7 yes Figure 4A 401, showing other dimensions of the adjustable annular treatment groove 408. For simplicity, the adjustment area of ​​the eyeglass 401 is not shown. Changes in curvature and tilt of the annular treatment groove 408 are indicated on the left hand side of the eyeglass 401. Changes in position of the annular treatment groove 408 are indicated on the right hand side of the eyeglass 401. Arrows indicate movement of fluid and / or tissue within the cornea 414;

[0031] Figure 8 yes Figure 4A 401, showing the size of the adjustable accommodation zone 410. Changes in curvature and changes in width of the accommodation zone 410 are indicated on the left hand side of the eyeglass 401. Changes in asphericity and symmetry of the accommodation zone 410 are indicated on the right hand side of the eyeglass 401. Arrows indicate movement of fluid and / or tissue within the cornea;

[0032] Fig. 9 A method 500 of manufacturing eyeglasses according to the present disclosure.

[0033] Fig.10 is another method 600 of manufacturing eyewear according to the present disclosure. DETAILED DESCRIPTION

[0034] According to the first aspect of the present disclosure, a corneal reshaping contact lens is provided. The corneal reshaping contact lens is used to correct and treat or slow down the progression of myopia by reshaping a portion of the cornea of ​​a myopic eye. The glasses have a rear surface for contacting the portion of the cornea to be reshaped. The rear surface of the glasses includes a correction area for reducing the curvature of the central portion of the cornea. The correction area is defined by a first section of the rear surface having a radius of curvature of 6 mm or greater. The rear surface of the glasses also includes an annular treatment groove for inducing myopic defocus in the peripheral portion of the cornea. The annular treatment groove extends radially outward from the periphery of the correction area and is defined by a second section of the rear surface having a radius of curvature less than the radius of curvature of the first section, and wherein the radius of curvature of the second section defining the annular treatment groove is such that the annular treatment groove is configured to induce at least +1D of myopic defocus in the peripheral portion of the cornea. The rear surface of the glasses also includes an adjustment area for adjusting the myopic defocus induced by the annular treatment groove. The modulation region extends radially outward from the periphery of the annular treatment groove and is defined by a third section of the rear surface having a radius of curvature in the range from 4.5 mm to 15 mm.

[0035] According to a second aspect, there is a method for manufacturing a corneal reshaping contact lens for correcting and treating myopia by reshaping a portion of the cornea of ​​a myopic eye. The corneal reshaping lens may be a lens according to the first aspect of the present disclosure. The method includes forming a rear surface of the lens for contacting a portion of the cornea to be reshaped. The method includes forming a first section of the rear surface, wherein the first section defines a correction area and has a radius of curvature of 6 mm or greater. The method further includes forming a second section of the rear surface, which extends radially outward from the periphery of the correction area. The second section defines an annular treatment groove and has a radius of curvature that is smaller than the radius of curvature of the first section. The radius of curvature of the second section is such that the annular treatment groove is configured to induce at least +1D of myopic defocus in the peripheral portion of the cornea. The method further includes forming a third section of the rear surface, which extends radially outward from the periphery of the annular treatment groove. The third section defines an accommodation area and has a radius of curvature in the range of 4.5 mm to 15 mm. The first, second and third sections of the rear surface of the lens can be formed sequentially or simultaneously using the method disclosed herein.

[0036] As used herein, the term "contact lens" or just "lens" refers to a lens that can be placed on the front surface of the eye. Orthokeratology contact lenses are a type of contact lens whose properties and features will be described herein. It should be understood that such contact lenses will provide clinically acceptable on-eye movement and will not adhere to a person's eye. The contact lens is in the form of a corneal lens (e.g., a lens that rests on the cornea of ​​the eye).

[0037] According to the present disclosure, the glasses are orthokeratology contact lenses (also referred to as "Ortho-K glasses"). It should be understood that reference to "glasses" according to the present disclosure is reference to orthokeratology glasses, unless another meaning is given. Conventional contact lenses correct myopia by reducing the convergence of light incoming from distant objects before it reaches the eye so that the position of the focal point is shifted to the retina. Therefore, conventional contact lenses must be worn on the cornea to improve vision. In contrast, orthokeratology glasses according to the present disclosure change the optical properties of the eye itself by gradually changing or reshaping the surface profile of the subject's cornea during continued wear. Reshaping the surface profile of the glasses provides temporary optical correction of myopia.

[0038] The disclosed orthokeratology lenses continuously apply pressure to selected locations of the cornea when worn to reshape the cornea into a desired surface profile. More specifically, orthokeratology contact lenses are worn on the cornea and reshape the epithelial layer of the cornea primarily by changing the distribution of fluids and / or tissues in the epithelial layer. It should be understood that reference to fluids and / or tissues refers to any organic or physiological material in the epithelial layer of the cornea that can be moved by a compressive force applied to the surface of the cornea. For example, the fluid of the epithelial layer of the cornea may include an aqueous solution of water and solutes commonly found in the cornea, which may also include a dispersion of organic materials commonly found in the cornea in an aqueous solution. Tissue may refer to cells or cell groups commonly found in the cornea. Orthokeratology lenses according to the present disclosure can reshape the cornea of ​​the eye so that a cornea having a radius of curvature that converges light before light from a distant object reaches the eye is reshaped into a cornea having a radius of curvature that reduces the convergence of light from a distant object so that the light is focused on the retina. Disclosed herein is a mechanism by which corneal fluid and / or tissue can be redistributed. After the orthokeratology contact lens is removed from contact with the cornea of ​​the eye, the reshaped surface contour of the cornea can be maintained. The reshaped surface contour of the cornea can be maintained for a long period of time after the lens is removed from contact with the cornea, so that the added visual acuity is maintained for several hours, such as up to 5 hours, up to 8 hours, up to 12 hours, or up to 16 hours, or one or more days. Thus, the optical correction imparted by the orthokeratology lens is maintained in the cornea even after the lens is removed.

[0039] The orthokeratology glasses disclosed herein are used to correct and treat myopia. It should be understood that correcting myopia refers to changing the optical properties of the eye so that the degree of myopia of the eye is reduced or eliminated and the vision is sufficient without the need for a corrective device (e.g., traditional contact lenses or frame glasses). For example, the eyes of a myopic person with a myopia between -0.25D and -15D may have a myopia reduction of at least 0.25D, at least 0.5D, or preferably at least 0.75D after wearing glasses according to the present disclosure. Orthokeratology glasses can be worn every night within a week to achieve myopic refractive error correction, sufficient to eliminate the need for traditional corrective devices, such as contact lenses or frame glasses. Preferably, correcting myopia causes the eye to no longer be myopic, so that hyperopia vision does not require external vision correction (e.g., wearing frame glasses or traditional contact lenses). Myopia can be corrected by glasses reducing the curvature of at least a central portion of the cornea. This can be achieved by orthokeratology glasses according to the mechanism described herein. It should be understood that it is necessary to correct myopia in the central portion of the cornea to correct distance vision. However, the peripheral portion of the cornea may remain uncorrected or even have increased myopia ("myopic defocus") without interfering with distance vision. For example, orthokeratology lenses according to the present disclosure may correct myopia in the central portion of the cornea while undercorrecting myopia or adding positive power in the peripheral portion of the cornea. This undercorrection or adding positive power in the peripheral portion may be described as introducing myopic defocus into the eye.

[0040] It will be understood that reference to treating myopia means slowing the progression of myopia. Treating myopia may result in a halt or reversal of the progression of myopia. This may be particularly beneficial in children, as myopia typically worsens as children age. Orthokeratology lenses may be used to prevent the onset of myopia in subjects at risk for myopia. Without wishing to be bound by theory, it is believed that the introduction of myopic defocus into the peripheral region of the cornea by lenses according to the present disclosure may be used to slow the progression of myopia or prevent its onset. The annular treatment groove of the orthokeratology lenses disclosed herein may induce myopic defocus in the cornea via the mechanisms disclosed herein.

[0041] The disclosed orthokeratology contact lenses may be rigid contact lenses composed of rigid materials. The lenses may be rigid gas permeable lenses. Orthokeratology lenses may be made of polymethyl methacrylate (PMMA) or copolymers of methyl fluoroacrylate and siloxane styrene, copolymers of fluoropolysilicone acrylate compounds, copolymers of polysilicone methyl acrylate compounds and fluoromethyl acrylate compounds. Examples of suitable lens materials include materials with the following United States Adopted Names (USAN): tisilfocon A, tolofocon A, paflufocon A, paflufocon B, paflufocon C. It should be understood that rigid lenses may be particularly effective in redistributing corneal fluid and / or tissue of the epithelial layer of the cornea, because the rigid structure may impart compressive forces to the corneal surface sufficient to displace fluid and / or tissue from one area of ​​the cornea to another area of ​​the cornea.

[0042] The term "lens body" may be used to refer to the bulk of the lens and may be used in particular to refer to a section of the lens bounded by the front and back surfaces. The lens body may be formed of a plurality of lens layers. "Lens layer" refers to an area of ​​lens material that forms at least a section of the lens body. If there are a plurality of lens layers, each lens layer will have a thickness that is less than the thickness of the lens body. The lens body optionally includes a lens layer attached to at least one other layer. For example, a plurality of layers (e.g., at least two or at least three lens layers) may be stacked to form the lens body. If there are a plurality of lens layers, the lens layers may be formed of the same or different materials. At least two of the lens layers may optionally be formed of the same material and at least one lens layer may be formed of alternative materials. If the lens body includes a plurality of lens layers, there may be a distinguishable boundary between each layer. For example, the lens body may be formed by curing a bulk material to form a first layer and laying down other materials on top of the first layer (which are then cured to form a second layer). If the first and second layers are formed of different materials, then obviously there is a boundary where the chemical composition of the materials changes between the layers. If the first and second lens layers are formed of the same material, there may be different physical properties between the layers, for example, different optical properties or crystallinity at the boundaries between the lens layers. It should be understood that when the lens is composed of more than one lens layer, the back surface of the lens refers to the back surface of the bottom layer (i.e., the layer that contacts the eye when the lens is worn). When the lens is composed of multiple layers, the front surface of the lens should be understood as the front surface of the top layer of the lens (i.e., the layer that is farthest from the surface of the eye when the lens is worn). The lens body can be formed by a single lens layer. It should be understood that if the lens body is formed by a single lens layer, the bulk material forming the lens body will be homogenous, so that there are no distinguishable boundaries between the areas of bulk material forming the lens body. When the lens body is formed by a single lens layer, the lens layer forms the entire lens body, in which case the terms "lens layer" and "lens body" can be used interchangeably. A single lens layer can form the entire lens.

[0043] When viewed in plan, the orthokeratology contact lens may be substantially circular and have a diameter in the range of from 8 mm to 25 mm. The diameter of the lens may optionally be in the range of from 8 mm to 15 mm.

[0044] The orthokeratology contact lens according to the present disclosure has a front surface and an opposing rear surface. When the contact lens is positioned on the eye, the front surface faces away from the eye, and the front surface may have a generally convex shape. When the contact lens is positioned on the eye, the rear surface is oriented toward the eye. The rear surface may have a generally concave shape. The rear surface of the lens contacts the cornea of ​​the eye. It should be understood that when the lens is worn, at least a major portion of the rear surface may contact the surface of the cornea, such as at least 50%, at least 75%, or at least 90%. The contact between the rear surface of the lens and the cornea allows the lens to reshape the surface of the cornea, as described herein.

[0045] The back surface of the orthokeratology lens comprises a correction zone. The correction zone is the area of ​​the back surface of the lens that reduces the curvature of the central portion of the cornea when the lens is worn. The lens is configured so that the correction zone is positioned over the pupil of the eye when the lens is in use. The correction zone is preferably positioned in the center of the lens around the central axis of the lens when the lens is viewed in a plane. The correction zone is aligned with the central portion of the cornea to be treated. The correction zone is preferably substantially circular when viewed in a plane.

[0046] The corrective zone is defined by a first section of the posterior surface having a radius of curvature greater than the radius of curvature of the central portion of the cornea. It will be appreciated that the larger the radius of curvature, the flatter the corrective zone.

[0047] The glasses are configured so that when they are worn, the correction area contacts the apex of the cornea and the central portion of the cornea is flattened due to compression because the central area has a flatter or more gently curved profile than the apex of the cornea. Thus, the correction area is configured to correct the hyperopic vision of a myopic person by flattening or reducing the curvature of the central portion of the treated cornea. Without wishing to be bound by theory, it is believed that the correction area reduces the curvature of the central portion of the cornea by displacing epithelial fluid and / or tissue from the central portion of the cornea to the central portion of the cornea. When orthokeratology glasses are worn, the central portion of the cornea will be at least partially molded or influenced by at least a portion of the correction area of ​​the glasses. Thus, the topology of the central portion of the cornea will be flatter after the glasses are worn than before the glasses were worn.

[0048] To address the refractive error of a myopic eye, the central portion of the cornea needs to be flattened or less curved. The minimum radius of curvature required for the correction zone of the eyeglass can be approximated to the radius of curvature required to correct a low myopic person (e.g., a -0.25D myopic person). Eyes with a higher degree of myopia will require greater flattening and therefore must have a correction zone with a radius of curvature greater than the radius of curvature of the correction zone required for a lower myopic person. Therefore, the maximum radius of curvature of the correction zone can be approximated to the radius of curvature required to correct a high myopic person (e.g., a -15D myopic person).

[0049] The corrective zone is defined by a first section of the back surface of the eyeglass having a radius of curvature of 6 mm or more, such as a radius of curvature of 7 mm or more or a radius of curvature of 8 mm or more. The corrective zone may be defined by a first section of the back surface of the eyeglass having a radius of curvature of less than 15 mm, less than 12 mm, or less than 10 mm. The radius of curvature of the corrective zone may be in the range of from 6 mm to 15 mm, from 6 mm to 12 mm, from 6 mm to 10 mm, from 6 mm to 9.5 mm, from 7 mm to 9.5 mm, from 7 mm to 9 mm, from 8 mm to 8.5 mm, from 8.8 mm to 9.3 mm, from 6 mm to 6.8 mm, or from 6.8 mm to 15 mm. When treating relatively low myopes (e.g., -1.0 D myopes), it may be advantageous to have a corrective zone with a radius of curvature in the range of from 7 mm to 9.5 mm. When treating relatively high myopes (eg, -4.0 D or greater), it may be advantageous to provide a correction zone defined by a portion of the back surface of the lens having a radius of curvature in the range from 6.8 mm to 15 mm.

[0050] The correction zone can provide additional correction above that required to correct myopia. This overcorrection takes into account the gradual reversal of the contour of the cornea to its untreated state over the course of a day when glasses are no longer worn. For example, an overcorrection of approximately -0.75D can be induced by the correction zone to allow the central portion of the cornea to partially reverse to its natural, more curved state when glasses are not worn. This overcorrection is called the Jessen factor. The overcorrection can be greater than -0.5D or greater than -1D or greater than -2D. Overcorrection can extend the period of time that the cornea will remain focused on distance vision when glasses are not worn. Overcorrection can also increase the volume of fluid and / or cells moving into the peripheral portion of the cornea because the central portion of the cornea will become flatter. This can help control the amount of myopic defocus induced by the annular treatment groove because a larger volume of fluid and / or cells are redistributed within the cornea.

[0051] The corrective region may have a diameter greater than 1 mm, greater than 2 mm, or greater than 3 mm. The corrective region may have a diameter less than 8 mm, less than 6 mm, less than 5 mm, or less than 4 mm. The corrective region may have a diameter in the range of from 1 mm to 8 mm, 2 mm to 6 mm, more preferably 2.5 mm to 5.5 mm, and most preferably in the range of from 3 mm to 4 mm. In a preferred embodiment, the corrective region has a diameter of about 3 mm, for example a diameter of about 3.36 mm.

[0052] The correction zone may be defined by a first segment of the rear surface of the eyeglass that is spherical. Alternatively, the correction zone may be defined by a first segment of the rear surface of the eyeglass that is aspherical. It should be understood that an aspherical profile is a profile in which the radius of curvature is not constant across a segment of the rear surface corresponding to the diameter of the correction zone. For example, the radius of curvature of the center of the correction zone may be greater than the radius of curvature at either or both ends of the correction zone. Alternatively, the radius of curvature of the center of the correction zone may be less than the radius of curvature at either or both ends of the correction zone. The radius of curvature may increase toward the edge of the correction zone. Alternatively, the radius of curvature may decrease toward the edge of the correction zone. An aspherical correction zone may advantageously achieve a more constant base power across the central portion of the cornea because the degree of flattening may decrease with radial distance from the vertex of the cornea. The correction zone may optionally be defined by a first segment of the rear surface configured to treat astigmatism. For example, the profile of the rear surface of the correction zone may be toric.

[0053] The rear surface of the eyeglass further comprises an annular treatment groove extending radially outward from the periphery of the corrective zone. The eyeglass is configured so that the annular treatment groove, together with the corrective zone, is aligned with the pupil of the eye when the eyeglass is in use. When the eyeglass is viewed in a plan, the central corrective zone is centered on the central axis of the eyeglass and the annular treatment groove surrounds the central corrective zone. When the eyeglass is worn, the annular treatment groove is aligned with the peripheral portion of the cornea to be treated. The annular treatment groove is preferably substantially circular when viewed in a plan.

[0054] The annular treatment groove induces myopic defocus in the peripheral portion of the cornea and is defined by a second section of the back surface having a radius of curvature that is smaller than the radius of curvature of the first section of the back surface (i.e., the correction zone). Because the radius of curvature of the annular treatment groove is smaller than the radius of curvature of the correction zone, the annular treatment groove is more curved and provides an additive power to the treated cornea. It should be understood that the shorter the radius of curvature of the second section of the back surface of the eyeglass, the more curved the annular treatment groove is and the greater the additive power. The annular treatment groove is formed in the back surface of the eyeglass, which is a concave surface.

[0055] When the glasses are in use, the annular treatment groove accommodates the increase in thickness and curvature of the peripheral portion of the cornea. The increased thickness / curvature is caused by the increase in pressure in the central area of ​​the cornea (caused by the corrective area of ​​the glasses) to cause fluid and / or tissue to be redistributed to the peripheral portion. It should be understood that the surface of the cornea presents a profile that is affected by the profile of the rear surface of the glasses because the surface of the cornea is compressed to at least partially conform to the shape of the rear surface of the glasses. Therefore, the peripheral portion of the cornea aligned with the annular treatment groove will be shaped by the annular treatment groove when the glasses are worn and will have an added (convex) curvature. The shaped peripheral portion of the cornea adds positive or myopic defocus to the cornea. The annular treatment groove controls the shape of the peripheral portion of the cornea that provides myopic defocus in the treated eye. It should be understood that the shape of the peripheral portion of the cornea does not necessarily match the shape of the annular treatment groove, for example, when the glasses are worn, the peripheral portion of the cornea may only partially fill the annular treatment groove.

[0056] The corrective zone of the eyeglass changes the central corneal curvature and provides a degree to the central portion of the cornea by flattening the zone. The annular treatment groove provides undercorrection of hyperopic vision or intentionally induces myopic defocus in the cornea. The radius of curvature of the second section of the peripheral portion of the eyeglass will cause the annular treatment groove to induce at least +1D of myopic defocus in the peripheral portion of the treated cornea, which exceeds the degree obtained by the flattened central portion of the cornea. It should be understood that diopter (D) is a unit of measurement of the refractive power of the eyeglass and is a common term in the art. The added degree provided by the annular treatment groove in the peripheral portion of the cornea may be at least +1.5D, at least +2.0D, at least +4.0D, at least +6.0D, at least +8.0D, or at least +12.0D, which exceeds the degree obtained by the flattened central portion of the cornea. The added degree provided by the annular treatment groove in the peripheral portion of the cornea may be less than +12.0D, less than +8.0D, or less than +6.0D. For example, the added power provided by the annular treatment groove in the peripheral portion of the cornea can be at least +1.0D but less than +12.0D. This is achieved by controlling the curvature of the annular treatment groove. The annular treatment groove can also help create a uniform correction area in the central portion of the cornea by accommodating at least some fluid and / or tissue displaced from the central portion of the cornea. As will be disclosed herein, the width, depth, curvature, and position of the annular treatment groove can affect the amount of redistributed fluid and / or tissue accommodated in the peripheral portion of the cornea.

[0057] The annular therapeutic groove induces myopic defocus in the peripheral portion of the cornea by allowing the curvature of the cornea to be less flattened, remain unflattened, or increase in the peripheral portion of the cornea positioned below the annular therapeutic groove when wearing glasses. The radius of curvature of the annular therapeutic groove will be selected according to the degree of flattening or increase in curvature desired in the peripheral portion of the cornea. The peripheral portion of the cornea will not be fully corrected for distance vision. Therefore, intentional undercorrection or myopic defocus will be introduced into the cornea in the peripheral portion. Without wishing to be bound by theory, it is believed that the myopic defocus induced in the peripheral portion of the cornea promotes slowing the progression of myopia. The size of the annular therapeutic groove can be modified to control the amount of myopic defocus induced and the location of the cornea where the defocus will be induced.

[0058] At the annular treatment groove, in the direction of the thickness of the lens, the lens comprises the groove and a residual portion of the lens material having a surface defining a closed end of the groove. The surface defining the closed end of the groove is a second section of the back surface of the lens. The second section of the back surface of the lens has a curvature that defines the curvature of the groove.

[0059] The depth of a groove is defined as the distance from the open end of the groove (i.e., the rear surface that would be present if the groove were not present) to the closed end of the groove (i.e., the surface of the lens material that defines the end of the groove). One or more grooves may have a depth between 3% and <100% of the thickness of the remainder of the lens material, for example, the groove may have a depth between 10% and 80%, 20% and 60%, or 30% and 50% of the thickness of the remainder.

[0060] The radius of curvature of the second section of the rear surface of the eyeglass defining the annular treatment groove may be in the range from 5.5 mm to 12 mm, for example, in the range from 6.5 mm to 12.0 mm, from 7.5 mm to 9.0 mm, from 8.0 mm to 9.0 mm, from 5.5 mm to 8.5 mm, from 7.5 mm to 8.5 mm or from 8.5 mm to 9.5 mm. The curvature of the second section of the rear surface of the eyeglass defining the annular treatment groove may be selected depending on the curvature of the correction zone. For example, when the radius of curvature of the first section of the rear surface of the eyeglass defining the correction zone is in the range from 8.0 mm to 8.5 mm, the radius of curvature of the second section of the rear surface of the eyeglass defining the correction zone may be in the range from 7.7 mm to 8.2 mm. When the radius of curvature of the first section of the rear surface of the eyeglass defining the correction zone is in the range from 8.8 mm to 9.3 mm, the radius of curvature of the second section of the rear surface of the eyeglass defining the correction zone may be in the range from 8.3 mm to 8.8 mm. The flatter (less curved) the corrective zone, the greater the amount of corneal fluid and / or tissue that will be displaced by the lens and a more curved annular treatment groove may be required. Alternatively, in relatively high myopes, the corrective zone may be flatter than for low myopes, but because the surface profile of the peripheral portion of the pre-treated cornea is already highly curved, the annular treatment groove may have a radius of curvature equal to or even less than the radius of curvature of the peripheral portion of the pre-treated cornea to protect or flatten the peripheral portion to obtain the desired myopic defocus. The radius of curvature of the second portion of the rear surface of the lens defining the annular treatment groove will be less than the radius of curvature of the first portion of the rear surface of the lens defining the corrective zone.

[0061] The annular treatment groove may have a width in the range of from 0.5 mm to 5.5 mm, from 1 mm to 4 mm, for example, in the range of from 1 mm to 2 mm. It will be appreciated that because the treatment groove is annular, the width may be defined as the distance between the periphery of the inner edge of the groove and the outer edge of the groove in the direction of travel from the center of the eyeglass to the edge of the eyeglass (when the eyeglass is viewed in a plane).

[0062] The annular therapeutic groove may be symmetrical or asymmetrical, i.e., the groove is defined by a second segment of the back surface of the eyeglass having a symmetrical or asymmetrical profile. The annular therapeutic groove may be defined by a second segment of the back surface of the eyeglass that is spherical. Alternatively, the annular therapeutic groove may be defined by a second segment of the back surface of the eyeglass that is aspherical. The shape of the groove may impart a specific optical power in the portion of the cornea that is aligned with the groove of the eyeglass. The annular therapeutic groove may be asymmetrical, such that the portion of the annular therapeutic groove positioned closest to the correction zone has a smaller radius of curvature than the portion of the annular therapeutic groove positioned farther from the correction zone. It should be understood that this asymmetrical profile tilts the annular therapeutic groove toward the correction zone. Alternatively, the annular therapeutic groove may be asymmetrical, such that the portion of the annular therapeutic groove positioned closest to the correction zone has a larger radius of curvature than the portion of the annular therapeutic groove positioned farther from the correction zone. It should be understood that this asymmetrical profile tilts the annular therapeutic groove away from the correction zone. The tilting of the annular therapeutic groove may help to direct tissue and / or fluid toward or away from the central portion of the cornea aligned with the correction zone. The radius of curvature of the annular treatment groove may depend on the radius of curvature of the correction zone.

[0063] The eyeglasses further include an adjustment zone extending radially outward from the periphery of the annular treatment groove. Thus, it should be understood that the adjustment zone is also annular or substantially annular and centered on the central axis of the eyeglasses when viewed in a plane. The adjustment zone adjusts the myopic defocus induced by the annular treatment groove and the central correction zone in the peripheral portion of the cornea. The adjustment zone adjusts the increase in curvature of the cornea in the peripheral portion caused by the increase in pressure within the cornea caused by the redistribution of fluid and / or tissue toward the peripheral portion and controls the movement of fluid and / or tissue from the far periphery of the cornea to the peripheral portion of the cornea aligned with the annular treatment groove, as will be explained herein. The adjustment zone may additionally or alternatively help achieve a central portion of the cornea with a uniform degree across its diameter. For example, the adjustment zone may serve as an additional groove for accommodating the increase in curvature of the cornea in the peripheral portion caused by the increase in pressure within the cornea caused by the redistribution of fluid and / or tissue toward the peripheral portion. The adjustment zone may be positioned outside the visual zone so as not to interfere with the user's vision. When the eyeglasses are in use, the adjustment zone may not overlap with the pupil of the eye.

[0064] The accommodation zone has a radius of curvature defined by a third section of the back surface of the eyeglass having a curvature that provides a degree in the range from 12 diopters greater than the radius of curvature of the correction zone to 12 diopters less than the radius of curvature of the correction zone. For example, the third section of the back surface of the eyeglass defining the accommodation zone may have a curvature that provides a degree in the range from 0 diopters to 12 diopters greater than the radius of curvature of the correction zone, from 0 diopters to 8 diopters greater than the radius of curvature of the correction zone, or from 0 diopters to 4 diopters greater than the radius of curvature of the correction zone. Alternatively, the third section of the back surface of the eyeglass defining the accommodation zone may have a curvature that provides a degree in the range from 0 diopters to 12 diopters less than the radius of curvature of the correction zone, from 0 diopters to 8 diopters less than the radius of curvature of the correction zone, or from 0 diopters to 4 diopters less than the radius of curvature of the correction zone.

[0065] The radius of curvature of the third section of the rear surface of the eyeglass defining the accommodation zone may be in the range of from 4.5 mm to 15 mm, for example, from 4.5 mm to 12 mm, from 7 mm to 15 mm, or from 7 mm to 9 mm. The accommodation zone may have a width in the range of from 0.5 mm to 5.5 mm, from 1 mm to 4 mm, for example, the width may be in the range of from 1 mm to 2 mm. The radius of curvature of the third section may be equal to the radius of curvature of the second section defining the correction zone.

[0066] The radius of curvature of the third section may be greater than the radius of curvature of the second section defining the corrective region, for example, at least 0.9 mm greater.

[0067] The radius of curvature of the third segment may be smaller than the radius of curvature of the second segment defining the correction zone, for example, at least 0.9 mm larger. It will be appreciated that because the adjustment zone is annular, the width may be defined as the distance between the periphery of the inner edge of the adjustment zone and the outer edge of the zone in a direction of travel from the center of the eyeglass to the edge of the eyeglass (when the eyeglass is viewed in a plane) .

[0068] The accommodation zone may be symmetrical, i.e., the accommodation zone may be defined by a third segment of the rear surface of the eyeglass having a symmetrical profile. The accommodation zone may be asymmetrical, i.e., the accommodation zone may be defined by a third segment of the rear surface of the eyeglass having an asymmetrical profile. The accommodation zone may be defined by a third segment of the rear surface of the eyeglass having a spherical surface. Alternatively, the accommodation zone may be defined by a third segment of the rear surface of the eyeglass having an aspherical surface. The shape of the accommodation zone may impart a specific optical power in the eyeglass. The accommodation zone may be asymmetrical, such that the portion of the accommodation zone positioned closest to the annular treatment groove has a smaller radius of curvature than the portion of the accommodation zone positioned further away from the annular treatment groove. It should be understood that this asymmetrical profile tilts the accommodation zone toward the annular treatment groove and the correction zone. Alternatively, the accommodation zone may be asymmetrical, such that the portion of the accommodation zone positioned closest to the annular treatment groove has a larger radius of curvature than the portion of the accommodation zone positioned further away from the annular treatment groove. It should be understood that this asymmetrical profile tilts the accommodation zone away from the annular treatment groove and the correction zone. This may help direct tissue and / or fluid towards or away from the portion of the cornea aligned with the annular treatment groove, as desired.The radius of curvature of the accommodation zone may be dependent on the radius of curvature of the corrective zone.

[0069] In some embodiments, the radius of curvature of the accommodation zone is less than the radius of curvature of the correction zone. In such embodiments, the accommodation zone can be used to accommodate fluid and / or tissue displaced by the correction zone that is not accommodated by the annular treatment groove of the eyeglasses. This can be particularly advantageous when the corrected degree of myopia is relatively high (e.g., -4.00D myopic). In this example, a relatively large amount of flattening of the central portion of the cornea is required and therefore a large volume of tissue and / or fluid is displaced through the correction zone of the eyeglasses. The volume of displaced tissue and / or fluid may be greater than that required to cause the desired myopic defocus in the peripheral portion of the cornea. It is desirable to avoid the accumulation of excessive displaced tissue and / or fluid in the peripheral portion of the cornea, as this will induce an additional degree that exceeds the desired area of ​​the cornea. To help achieve the desired amount of myopic defocus in the peripheral portion of the cornea in a clearly defined area, the accommodation zone can act as a reservoir for accommodating excess displaced tissue and / or fluid. In this case, the accommodation zone is the area of ​​the eyeglasses into which the curvature of the cornea can extend. Thus, the accommodation zone in this embodiment may be considered a second groove and may have any of the features disclosed with respect to the annular treatment groove.The accommodation zone in this embodiment may induce a second myopic defocus into the cornea.

[0070] The orthokeratology lens optionally includes a correction zone defined by a first segment of the back surface of the lens having a radius of curvature in the range from 6.8 mm to 15.0 mm, and the radius of curvature of the third segment of the back surface defining the accommodation zone is in the range from 4.5 mm to 15 mm and is smaller than the radius of curvature of the first segment of the back surface defining the correction zone. The radius of curvature of the second segment of the back surface of the lens defining the annular treatment groove is optionally in the range from 6.5 mm to 12.0 mm, as long as the radius of curvature is smaller than the radius of curvature of the correction zone. The radius of curvature of the third segment of the back surface of the lens defining the accommodation zone is optionally smaller than the radius of curvature of the second segment defining the annular treatment groove. For example, when the radius of curvature of the first section of the back surface of the eyeglass defining the correction zone is in the range of 8.8 mm to 9.3 mm, the radius of curvature of the second section of the back surface defining the annular treatment groove may be in the range of 8.3 mm to 8.8 mm, and the radius of curvature of the third section of the back surface defining the adjustment zone may be in the range of 7.9 mm to 8.4 mm. Such eyeglasses may be particularly effective in correcting and treating high myopia, such as myopia of at least -4.0D.

[0071] In some embodiments, the radius of curvature of the accommodation zone is greater than or equal to the radius of curvature of the correction zone. In such embodiments, the accommodation zone can be used to guide fluid and / or tissue displaced by the correction zone toward the portion of the cornea aligned with the annular treatment groove of the eyeglass. This may be particularly advantageous when the corrected degree of myopia is relatively low (e.g., -1.0D myopic). In this example, a relatively small amount of flattening of the central portion of the cornea and therefore a small volume of tissue and / or fluid is displaced through the correction zone of the eyeglass. To ensure that the annular treatment groove is able to induce sufficient myopic defocus in the peripheral portion of the cornea, the larger (flatter) radius of curvature of the accommodation zone may help guide tissue and / or fluid toward the region of the cornea aligned with the correction zone. When the accommodation zone is relatively flat, it may not act as a reservoir in which the cornea can expand, and thus inhibit fluid and / or tissue from moving from the central portion of the cornea and / or the peripheral portion of the cornea toward the region aligned with the accommodation zone.

[0072] The orthokeratology lens optionally includes a correction zone defined by a first segment of the back surface having a radius of curvature in the range from 7 mm to 9.5 mm, and a second segment of the back surface defining an annular treatment groove has a radius of curvature in the range from 5.5 mm to 8.5 mm, as long as the radius of curvature is less than the radius of curvature of the central correction zone. The radius of curvature of the accommodation zone is optionally in the range from 7.0 mm to 15 mm and the radius of curvature of the third segment is greater than the radius of curvature of the second segment defining the annular treatment groove. The case where the radius of curvature of the accommodation zone is greater than or equal to the radius of curvature of the correction zone. For example, when the radius of curvature of the first segment of the back surface of the lens defining the correction zone is in the range from 8.0 mm to 8.5 mm, the radius of curvature of the second segment of the back surface defining the annular treatment groove may be in the range from 7.7 mm to 8.2 mm, and the radius of curvature of the third segment of the back surface defining the accommodation zone may be in the range from 8.0 mm to 8.5 mm. The glasses are particularly effective in correcting and treating low myopia, such as myopia of about -1.0D.

[0073] The accommodation zone may be positioned in the rear surface of the eyeglass so that it is tilted toward or away from the center of the correction zone. It should be understood that the tilt in the accommodation zone may be created by creating an asymmetric profile in the third section of the rear surface of the eyeglass. The accommodation zone may be asymmetric so that the portion of the accommodation zone positioned closest to the annular treatment groove has a smaller radius of curvature than the portion of the accommodation zone positioned farther away from the annular treatment groove. It should be understood that this asymmetric profile tilts the accommodation zone toward the annular treatment groove and the correction zone. Alternatively, the accommodation zone may be asymmetric so that the portion of the accommodation zone positioned closest to the annular treatment groove has a larger radius of curvature than the portion of the accommodation zone positioned farther away from the annular treatment groove. It should be understood that this asymmetric profile tilts the accommodation zone away from the annular treatment groove and the correction zone. The tilt direction of the accommodation zone may be selected based on the desired flow direction of tissue and / or fluid in the cornea. For example, in an eyeglass designed to treat low myopia (e.g., -1.0D myopia), the accommodation zone may be tilted away from the annular treatment groove and the correction zone. This can direct corneal fluid and / or tissue toward the portion of the cornea bounded by the annular treatment groove and the correction zone and / or prevent fluid and / or tissue from moving toward the outer region of the cornea that can be bounded by the mating zone. In this arrangement, more fluid and / or tissue can be used to align with the annular treatment groove and / or the correction zone, which can help achieve the desired corneal profile in these areas. In glasses designed to treat high myopia (e.g., -4.0D myopia), the adjustment zone can be tilted toward the annular treatment groove and the correction zone. This can direct corneal fluid and / or tissue toward the outer region of the cornea that can be bounded by the mating zone and / or away from the portion of the cornea bounded by the annular treatment groove and the correction zone. If the adjustment zone is tilted toward the annular treatment groove and the correction zone, then the corneal fluid and / or tissue directed from the central portion of the cornea can be directed toward the outer region of the cornea that can be aligned with the mating zone. This arrangement can also prevent corneal tissue and / or fluid from flowing back from the outer region of the cornea toward the central region. Such a configuration in the lens can allow excess corneal fluid and / or tissue to be directed away from the annular treatment groove so that the desired myopic defocus in the peripheral portion of the lens can be controlled.

[0074] Eyeglasses according to the present disclosure may optionally include an accommodation region directly adjacent to the annular treatment groove, i.e., the outer periphery of the annular treatment groove may define a boundary between the annular treatment groove and the accommodation region. Thus, the treatment groove may be adjacent to the accommodation region. At the boundary between the adjacent accommodation region and the annular treatment groove, there may be an abrupt discontinuous increase or decrease in degree of radius of curvature, depending on the relative degrees of radius of curvature additive of the annular treatment groove and the accommodation region, respectively.

[0075] The radius of curvature of the accommodation zone can be equal to the radius of curvature of the annular treatment groove. In this embodiment, the accommodation zone and the annular treatment groove can be separated in the eyeglass so that there is a clear demarcation between the end of one zone and the beginning of the other zone. For example, a portion of the back eyeglass having a radius of curvature equal to the radius of curvature of the accommodation zone can separate the annular treatment groove from the accommodation zone.

[0076] Other one or more zones may be positioned between the annular treatment groove and the corrective zone. Such zones may direct tissue and / or fluid toward the peripheral portion of the cornea that is positioned below the annular treatment groove when the lens is in use. For example, the zones may have properties similar to the accommodation zones described herein, except that they are positioned on opposite sides of the treatment groove, i.e., they are aligned with the inner and outer peripheries of the annular treatment groove. Alternatively, such zones may divert tissue and / or fluid away from the portion of the cornea that is positioned below the annular treatment groove when the lens is in use. For example, the zones may have properties similar to the annular treatment groove.

[0077] The rear surface of the eyeglass may optionally further include a fitting area for securing the eyeglass to the cornea, wherein the fitting area extends radially outward from the periphery of the accommodation area. Thus, an eyeglass according to the present disclosure may include a fitting area for stabilizing the eyeglass.

[0078] The fitting area is the portion of the eyeglass outside the visual zone, so when the eyeglass is in use, the fitting area is not aligned with the pupil of the eye, but is outside the peripheral portion of the cornea. When the eyeglass is viewed in a plane, the fitting area is centered on the central axis of the eyeglass and surrounds the accommodation area. When viewed in a plane, the fitting area is preferably substantially circular. The fitting area has no optical properties, but is instead used to anchor the eyeglass to the eye when in use. This can help to avoid the eyeglass moving or sliding on the eye when in use. The fitting area optionally has a radius of curvature that is similar to the radius of curvature of the portion of the eye to be treated. The fitting area may have multiple areas, each area having a different radius of curvature. Each area may have a radius of curvature in the range of from 8mm to 12mm (preferably from 8.5mm to 10.5m), for example, the radius of curvature may be about 9mm. The fitting area may be rigid so that it does not flex or deform under the pressure of the fluid redistributed in the cornea. In this way, the fitting area helps to guide the fluid / cells into the area of ​​the cornea aligned with the annular area. The fitting area may optionally have a radius of curvature greater than the portion of the cornea that is aligned with the fitting area when the glasses are in use. In this way, the fitting area may apply additional pressure to the eye (e.g., additional pressure is applied to the side of the cornea by the fitting area). This may beneficially redistribute corneal tissue and / or fluid toward the center of the cornea, which may be preferred in glasses designed to treat relatively low myopia. Alternatively, the fitting area may have a radius of curvature greater than the portion of the cornea that is aligned with the fitting area when the glasses are in use. This fitting area will be more curved than the portion of the cornea that the fitting area is aligned with and thus the fitting area may not apply additional pressure to the cornea. This may allow the eye to expand in the area aligned with the fitting area (i.e., the side of the cornea), which may be preferred in glasses designed to treat relatively high myopia. The fitting area may have a width of at least 1 mm, or at least 2 mm, or at least 4 mm. The fitting area may have a width of no more than 9 mm, no more than 7 mm, or no more than 5 mm. For example, the fitting area may have a width in the range of from 1 mm to 7 mm (e.g., 1.5 mm). It will be appreciated that because the engagement zone is annular, the width may be defined as the distance between the periphery of the inner edge of the engagement zone and the outer edge of the engagement zone running from the center to the edge of the eyeglass (when the eyeglass is viewed in a plane).

[0079] The glasses optionally include an edge lift. The edge lift can help the user lift the glasses from the cornea.

[0080] A method of forming an orthokeratology lens according to the present disclosure may include any of the features set forth above.

[0081] The orthokeratology lens according to the present disclosure may optionally reshape the profile of the cornea to simulate the core properties of the MISIGHT contact lens. That is, the lens may provide a corneal profile that includes a central correction zone (the central portion of the cornea that has been flattened) having a diameter of 3.30 mm to 3.40 mm and an elevated peripheral portion (the peripheral portion of the cornea that already has increased curvature or myopic defocus) that provides an additive power of +2.0D and optionally has a diameter of 1.40 mm to 1.50 mm.

[0082] The eyeglasses can be formed by a cast molding process, a spin casting molding process, or a milling process, or a combination thereof. Those skilled in the art will appreciate that cast molding refers to molding the eyeglasses by placing an eyeglass forming material between a female mold piece having a concave eyeglass component forming surface and a male mold piece having a convex eyeglass component forming surface.

[0083] The manufacturing method may include forming a female mold piece having a concave lens forming surface and a male mold piece having a convex lens forming surface. The method may include filling a gap between the female and male mold pieces with a bulk lens material. The method may further include curing the bulk lens material to form the lens. It should be understood that the back and front surfaces of the lens will conform to the concave and convex surfaces and the mold and therefore the contours of the lens surfaces are controlled by the contours of the mold surfaces.

[0084] At least one of the annular treatment groove and the accommodation zone can be formed in the lens layer by milling, etching or lasering the groove or zone into the lens layer. A lens body having a rear surface can be first formed without at least one of the annular treatment groove and the accommodation zone (for example) in a mold. After the annular treatment groove and the accommodation zone are formed, the rear surface of the lens body can form the rear surface of the lens. The lens body can have a substantially uniform radius of curvature across the rear surface. The radius of curvature across the entire rear surface can be equal to the radius of curvature of the correction zone. The method then includes forming a second section of the rear surface defining the annular treatment groove and / or a third section of the rear surface defining the accommodation zone, removing portions of the lens body using milling, etching or lasering. In this way, after the lens body is formed, portions of the lens body can be removed using milling, etching or lasering to form a desired lens having a rear surface according to the present disclosure. This technique can be used to change the curvature of a section or sections of the rear surface of the lens body and thus create an annular treatment groove or accommodation zone on the rear surface. The resulting lens will have a rear surface according to the present disclosure.

[0085] Alternatively or in addition, at least one of the annular treatment groove and the accommodation zone may be formed in the lens layer by using a mold. The surface of the mold may optionally define at least one of: a first segment of the rear surface defining the correction zone, a second segment of the rear surface defining the annular treatment groove, and a third segment of the rear surface defining the accommodation zone of the lens. The mold may define the correction zone of the lens, and the annular treatment groove and the accommodation zone are formed by another process disclosed herein, such as milling, etching, or laser. The mold may include one or more protrusions for defining at least one of the correction zone, the annular treatment groove, or the accommodation zone. The shape and curvature of the protrusion will define the radius of curvature of the segment of the rear surface of the lens defining the annular treatment groove or the accommodation zone.

[0086] At least one of the annular treatment groove and the accommodation zone may additionally or alternatively be formed by holding the eyeglass in place while pressing the impression-forming arm into the rear surface of the eyeglass. This may be done multiple times, with impression arms of different diameters used to form impressions of different sizes in the rear surface of the eyeglass. The shape and curvature of the impression-forming arm will define the radius of curvature of the section of the rear surface of the eyeglass that defines the annular treatment groove of the accommodation zone.

[0087] Those skilled in the art will appreciate that the order of steps recited in the method of the first aspect or any other aspect of the present disclosure is not limited to the order presented.

[0088] According to a third aspect of the present disclosure is a method for manufacturing a corneal reshaping contact lens,

[0089] wherein the eyeglass comprises a rear surface having a plurality of segments, each segment having a radius of curvature, wherein a first segment defines a corrective region of the eyeglass, a second segment defines an annular therapeutic groove of the eyeglass, and a third radius segment defines an accommodation region of the eyeglass;

[0090] The method includes selecting the radius of curvature of each segment by:

[0091] i) selecting a radius of curvature of the first section, wherein the radius of curvature of the first section is at least 6 mm,

[0092] ii) selecting a radius of curvature of the second section, wherein the radius of curvature of the second section is smaller than the radius of curvature of the first section; and

[0093] iii) selecting a radius of curvature of the third section, wherein the radius of curvature of the third section is in the range from 4.5 mm to 15 mm; and,

[0094] iv) manufacturing the spectacles so that the back surface has a plurality of sections having the radii of curvature selected in steps i), ii) and iii) respectively.

[0095] It should be understood that any feature of the first or second aspect of the present disclosure may be combined with the third aspect of the present disclosure. For example, the method according to the third aspect may be used to manufacture glasses according to the first aspect. The correction area, annular treatment groove and adjustment area of ​​the third aspect may have any features described relative to the first or second aspect of the present disclosure. In addition, the method of the third aspect of the present disclosure may include any features of the second aspect of the present disclosure. For example, the glasses may be formed in a mold. At least one of the annular treatment groove and the adjustment area may optionally be formed by milling.

[0096] According to a fourth aspect of the present disclosure is a method for treating myopia progression, which includes providing glasses according to the present disclosure to a subject in need thereof. It should be understood that the subject is a person with myopia and the method includes treating the myopia of the person. The subject may be under 25 years old. The subject may be under 20 years old or under 15 years old. The subject may be under 12 years old. The orthokeratology glasses according to the present disclosure can be particularly advantageous for treating myopia in children under 12 years old. In children under 12 years old, myopia has not developed and is only mild and is therefore easy to slow or prevent its progression or deterioration. The use of orthokeratology glasses according to the present disclosure can be particularly effective in preventing the development of myopia or at least slowing the progression of myopia in subjects with a family history of developing myopia (i.e., a genetic predisposition).

[0097] A method for treating myopia progression may include reshaping a subject's cornea by fitting glasses according to the present disclosure to the subject's cornea. The method may correct myopia so that when the glasses are removed from the eye, the subject has clear distance vision. The method may induce myopic defocus in a peripheral region of the cornea, as described herein. For example, the method may induce myopic defocus of at least +1D, at least +1.5D, at least +2D, at least +4D, at least +6D, or at least +8D in the cornea. The correction area of ​​the cornea and the radius of the myopic defocus area of ​​the cornea may be defined by the correction area of ​​the glasses and the treatment groove, respectively. For example, a correction area in a pair of glasses having a diameter of about 3 mm may induce a correction of about 3 mm in diameter in the central portion of the cornea.

[0098] After fitting to the subject's eye, the glasses can be worn for a time sufficient to reshape the cornea to conform to the shape of the glasses or at least substantially conform to the shape of the glasses. For example, the glasses can be worn for at least 5 hours or at least 8 hours. The glasses are preferably worn all night while the subject is sleeping so that the cornea of ​​the eye can be reshaped when the subject does not need his vision. After reshaping the cornea so that the cornea has a profile substantially the same as the back surface of the glasses, the glasses can be removed. The reshaped profile of the cornea can last for several hours, for example, at least 5 hours, at least 8 hours, or at least 12 hours. Therefore, the subject's distance vision is enhanced compared to the natural state of the eye (i.e., the subject's vision before treatment with the glasses). After removing the glasses from the eye, the cornea is no longer subjected to compressive forces and the cornea will therefore return to its natural state. The glasses can be worn again to reshape the cornea again. Therefore, the subject can wear the glasses every night and remove the glasses during the day.

[0099] The present disclosure seeks to control the location and degree characteristics of myopic defocus produced in the peripheral portion of the cornea by corrective flattening of the central portion of the cornea. Additionally or alternatively, the present disclosure seeks to control the size and curvature of the corrective central portion of the cornea. This can be achieved by using the annular treatment grooves and accommodation zones in the orthokeratology lenses described herein.

[0100] According to the present disclosure, the orthokeratology contact lens 201 ( Figure 2A ) may be suitable for correcting and treating relatively high myopia (e.g., -4D myopia). Glasses 201 are configured to be worn on the cornea of ​​an eye (not shown). Glasses 201 include a rear surface 202 and a front surface 204. A first section of the rear surface 202 defines a central correction region 206. The first section of the rear surface 202 that defines the central correction region 206 has a radius of curvature that is smaller than the radius of curvature of the cornea. A second section of the rear surface 202 defines an annular treatment groove 208. The annular treatment groove 208 is defined by a second section of the rear surface having a radius of curvature that is smaller than the radius of curvature of the correction region 206. A third section of the rear surface 202 defines an accommodation region 210. The accommodation region 210 is defined by a third section of the rear surface having a radius of curvature that is smaller than both the radius of curvature of the correction region 206 and the radius of curvature of the annular treatment groove 208. A fitting region 212 is at the periphery of the glasses. The fit region 212 helps to stabilize the eyeglass 201 to the eye when in use. The fit region 212 may have a continuous radius of curvature across its width, or it may have multiple radii of curvature across its width.

[0101] Glasses 201 include four concentric areas ( Figure 2B). Each zone is centered on the axis of the eyeglass 201. The central portion of the eyeglass 201 is the correction zone 206. An annular treatment groove 208 extends radially outward from the periphery of the correction zone 206. The adjustment zone 210 is adjacent to the annular treatment groove 208. The outermost zone of the eyeglass 201 is the fitting zone 212.

[0102] Orthokeratology contact lenses 301( Figure 3A ) may be suitable for correcting and treating relatively low myopia (e.g., -1D myopia). Glasses 301 are configured to be worn on the cornea of ​​an eye (not shown). Glasses 301 include a rear surface 302 and a front surface 304. A first section of the rear surface 302 defines a central correction region 306. The first section of the rear surface 302 defining the correction region 306 has a radius of curvature that is smaller than the radius of curvature of the cornea (not shown) to be treated. Because the glasses are suitable for treating relatively low myopia, the correction region 306 may be relatively Figure 2A 306 is more curved or less flat. A second section of the back surface 302 defines an annular treatment groove 308. The annular treatment groove 308 is defined by a second section of the back surface 302 having a radius of curvature that is less than the radius of curvature of the correction zone 306. A third section of the back surface 302 defines an accommodation zone 310. The accommodation zone 310 is defined by a third section of the back surface 302 of the eyeglass 301 having a radius of curvature that is equal to the radius of curvature of the correction zone 306 and a radius of curvature that is greater than the radius of curvature of the annular treatment groove 308. Figure 2A Compared with the glasses 201 shown in Figure 3A 301 has a relatively flat adjustment zone 310. A fit zone 312 is at the periphery of the eyeglasses. The fit zone 312 helps stabilize the eyeglasses 301 to the eye when in use. The fit zone 312 may have a continuous radius of curvature across its width, or it may have multiple radii of curvature across its width.

[0103] Glasses 301 include four concentric areas ( Figure 3B ). Each zone is centered on the axis of the eyeglass 301. The central portion of the eyeglass 301 is the correction zone 306. An annular treatment groove 308 extends radially outward from the periphery of the correction zone 306. The adjustment zone 310 is adjacent to the annular treatment groove 308. The outermost area of ​​the eyeglass 301 is the fitting zone 312.

[0104] In use, the orthokeratology contact lens 401 is placed on the cornea 414 ( Figure 4A414) (only the uppermost surface of the cornea 414 is shown, it should be understood that the uppermost surface of the cornea includes the epithelial layer 416). The correction area 406 is aligned with the central portion of the cornea 414 including the apex of the surface of the cornea 414. The annular treatment groove 408 is aligned with the peripheral portion of the surface of the cornea 414. For simplicity, the adjustment area is not shown. Figure 4A 408 and the mating area 412. Figure 4A Different shading is used in the image to indicate different areas of the glasses.

[0105] The structure of the corneal epithelial layer 416 of the cornea 414 means that the epithelial layer 416 of the cornea 414 is flexible and moldable. The structure and physiology of the corneal epithelium allow its thickness to be altered by the application of sustained pressure. Fluid and / or tissue of the corneal epithelial layer 416 (and other organic materials typically found in the eye) can be redistributed from one area of ​​the cornea 414 to another by applying pressure to the surface of the cornea 414. Because the radius of curvature of the correction area 406 of the eyeglass 401 is smaller than the radius of curvature of the cornea 414 to be treated, the correction area 406 contacts at least a central portion of the cornea 414 and applies pressure or compression (such as by Figure 4A This causes fluid and / or tissue of the corneal epithelium 416 to be forced into the peripheral portion of the cornea 414, as shown in FIG. Figure 4A 414 by arrows radiating from the center of the cornea 414. The annular treatment groove 408 is aligned with the peripheral portion of the cornea 414 and provides space for the cornea 414 to expand into due to the redistribution of cells / fluid from the central area of ​​the cornea 414 to the peripheral portion.

[0106] The surface profile of the cornea 414 before treatment (dashed line) is different from the surface profile of the cornea 414 after treatment (bold line). Figure 4B ). Thus, the redistribution of fluid and / or cells in the epithelial layer 416 of the cornea 414 can be used to reduce or increase the corneal curvature and therefore the optical power. The central portion of the cornea 414 aligned with the correction area 406 has been flattened, or is less curved in the treated cornea 414 than the cornea 414 before treatment. Because the central portion of the treated cornea 414 is less curved, the focus of light reflected from distant objects will be centered on the retina rather than in front of the retina, thereby correcting vision. In contrast, the peripheral portion of the cornea 414 adjacent to the annular treatment groove 408 is a lifted portion or a portion of the treated cornea 414 that is more curved than before treatment. Because the peripheral portion of the cornea 414 is more curved after treatment than the central portion, a positive power is induced compared to the base power of the central portion. This added power or myopic defocus area in the peripheral portion of the eyeglass is considered to slow or limit the progression of myopia.

[0107] Even when the eyeglass 401 is removed from the eye, the shape of the corrected cornea 414 is maintained. The shape of the cornea 414 will relax toward its uncorrected or pre-treatment state over time. When the shape of the cornea 414 has returned to its uncorrected state to the extent that distance vision is impaired, the eyeglass 410 can be placed back on the cornea 414 to reshape the contour of the cornea 414 once again.

[0108] According to the present disclosure, the dimensions including the diameter, width, curvature and shape of each of the correction area of ​​the glasses, the annular treatment groove and the adjustment area can be adjusted to affect the surface profile induced in the treated cornea. For example, the diameter of the correction area of ​​the glasses will affect the diameter of the central portion of the flattened cornea. It is desirable to provide a standard diameter of the central portion of the flattened cornea between all myopes treated with glasses according to the present disclosure. This can be achieved by selecting the diameter of the correction area of ​​the glasses, which will induce correction of the diameter of the central portion of the cornea that is the same across all myopes treated, for example, the diameter of the central portion of the cornea corrected by the correction area of ​​the glasses can be about 3 mm. The diameter of the correction area can be selected depending on the degree of myopia to be treated. For example, glasses for treating low myopia may have a correction area with a diameter that is smaller than the correction area of ​​glasses for treating higher myopia. However, the radius of curvature of the correction area of ​​the glasses will vary between glasses depending on the degree of myopia being treated, because higher myopia requires greater flattening. In general, the greater the amount of myopic refractive error to be corrected, the flatter the correction zone (i.e., the larger the radius of curvature of the correction zone). The annular treatment groove of the eyeglass always has a curvature greater than the central correction zone of the eyeglass to provide added power to the cornea. The radius of curvature width and shape of the annular treatment groove can be adjusted for each eyeglass depending on the radius of curvature of the correction zone. Similarly, the function of the adjustment zone of the eyeglass also depends on the size of the correction zone and therefore, the size of this zone will vary with the correction zone curvature or the amount of myopia to be corrected. As explained herein, the adjustment zone can be a groove for accommodating corneal volume during treatment, or alternatively, the adjustment zone can be a flatter, inclined zone for reducing or promoting volume accommodation in the peripheral portion of the cornea aligned with the annular treatment groove of the eyeglass. The greater the difference in power between the correction zone and the annular treatment groove, the flatter the adjustment zone can be (i.e., the larger the radius of curvature of the adjustment zone). For example, the power difference between the correction zone and the annular treatment groove may be +1D, +1.5D, +2D, +2.5D, +3D, +3.5D, +4D, +4.5D, +5D, +5.5D, +6D, +6.5D, or +7D. It should be understood that the power difference refers to the difference in power induced in the central portion of the cornea aligned with the correction zone and the peripheral portion of the cornea aligned with the annular treatment groove. The accommodation zone has a radius of curvature so that sufficient epithelial fluid and / or tissue is distributed to the peripheral portion of the cornea to induce the desired myopic defocus. When the power difference between the correction zone and the annular treatment groove of the eyeglass is large, the amount of epithelial tissue and / or fluid displaced by the correction zone may be insufficient, and therefore the amount of tissue and / or fluid directed toward the peripheral portion of the cornea is insufficient to induce the desired myopic defocus. Additionally or alternatively, it may be desirable to direct substantially all of the displaced fluid and / or tissue to a peripheral portion of the cornea aligned with the treatment groove and thus to avoid movement of displaced tissue and / or fluid toward the periphery of the cornea.Thus, when the difference in power between the corrective zone of the eyeglass and the annular treatment groove is large, a flatter accommodation zone may be desired to direct tissue and / or fluid toward the peripheral portion of the cornea aligned with the annular treatment groove. In contrast, when the difference in power between the corrective zone and the annular treatment groove is small, sufficient fluid and / or tissue may be directed to the peripheral portion of the cornea aligned with the annular treatment groove. In this case, the accommodation zone may be desired to be a groove for accommodating excess displaced fluid and / or tissue. Thus, when the difference in power between the corrective zone of the eyeglass and the annular treatment groove is small, a more curved accommodation zone (i.e., groove) may be desired to direct tissue and / or fluid toward the peripheral portion of the cornea aligned with the annular treatment groove. It should be understood that "adjustment," "variation," or the like of the size of a region of a reference eyeglass does not refer to changing the size of the eyeglass after it is formed, but rather to being able to design the eyeglass by selecting from a variety of sizes and then manufacturing the eyeglass according to the selected size. Reference will now be made to. Figures 5 to 8 to describe the various sizes that can be adjusted. The arrows in the figure indicate that fluid and / or tissue move within the cornea according to the contours of the correction zone, annular treatment groove, and accommodation zone. The following embodiments relate to glasses suitable for inducing +2D myopic defocus in the peripheral portion of the cornea. It should be understood that glasses according to the present disclosure can be designed to induce less than +2D or more than +2D myopic defocus in the peripheral portion of the glasses. The dimensions of the correction zone, annular treatment groove, and accommodation zone will be selected depending on the desired myopic defocus to be induced in the peripheral portion of the glasses, as described herein.

[0109] Certain areas and contours of the eyeglasses 401 may be modified to induce specific optical contours in the cornea ( Figure 5 ).for Figure 5 , the left and right hand sides of the eyeglass 401 show different profiles of the areas of the eyeglass, but it should be understood that this is merely illustrative of the various sizes of the areas that can be modified. It should be understood that the eyeglasses according to the present disclosure may include areas whose sizes are uniform across all meridians of the eyeglass. The diameter of the central correction area 406 of the eyeglass 401 can be made smaller or larger depending on the desired diameter of the central portion of the cornea 414 to be flattened. The curvature of the correction area 406 can also be modified depending on the amount of myopia to be corrected. For example, a flatter or less curved central correction area 406 can effectively treat high myopia (e.g., a myopic person of -4.0D) and a more curved central correction area 406 can effectively treat low myopia (e.g., a myopic person of -1.0D). The shape of the central correction area 406 can also be modified. For example, the central correction area 406 can be symmetrical, or it can be asymmetrical. The shape of the correction area 406 can be aspherical. An aspherical profile can be particularly advantageous in providing a more uniform profile across the central portion of the corrected cornea. In a similar manner, the annular treatment groove 408 and the adjustment area ( Figure 5The shape, diameter, and width of the mating region 412 (not shown) may also be modified. In addition, the dimensions of the mating region 412 may be modified to control the redistribution of fluid and / or tissue of the corneal epithelial layer 416. For example, the curvature of the mating region 412 may be made steeper or flatter. It should be understood that in Figure 5 4, the left hand side of the eyeglass 401 has a steeper fit area 412 that is steeper than the corneal surface profile 414. The steeper fit area 412 will push the sides of the cornea 414 to move fluid toward the center of the cornea 414. The right hand side of the eyeglass 401 shows a fit area 412 that is less steep than the cornea 414. The less steep fit area 412 allows the sides of the cornea 414 to expand and thus fluid and / or tissue of the corneal epithelium 416 to be redistributed away from the center of the cornea 414 toward the sides of the cornea 414. The fit area 412 may include multiple areas, each area having a different radius of curvature. Thus, the pressure applied by this area of ​​the eyeglass may be more accurately controlled.

[0110] The dimensions of the annular treatment groove of the eyeglasses can be modified. Figure 6 , on the left hand side of the eyeglass 401, the width change of the annular treatment groove 408 is indicated (numbers are marked only on the left hand side). On the right hand side of the eyeglass 401, the inclination or asphericity change of the annular treatment groove 408 is indicated. The annular treatment groove 408 may be inclined toward the central correction zone 406, or the annular treatment groove 408 may be inclined away from the central correction zone 406. The inclination of the annular treatment groove 408 may be used to control the flow direction of tissue and / or fluid of the epithelial layer 416 of the cornea 414. For example, when the annular treatment groove 408 is inclined away from the central correction zone 406, the tissue and / or fluid of the epithelial layer 416 may be prevented from moving toward the periphery of the cornea 414. This may be advantageous for treating low myopia. In contrast, when the annular treatment groove 408 is inclined toward the central correction zone 406, the tissue and / or fluid of the epithelial layer 416 may be promoted to move toward the periphery of the cornea 414. This may be advantageous for treating high myopia.

[0111] Other dimensions of the annular treatment groove can also be adjusted ( Figure 7 ). For simplicity, the accommodation area of ​​the eyeglass 401 is not shown. The change in curvature of the annular therapeutic groove 408 (numbers are marked only on the right-hand side) is indicated on the left-hand side of the eyeglass 401. The curvature of the annular therapeutic groove 408 affects the myopic defocus induced in the cornea 414. The smaller the radius of curvature of the annular therapeutic groove 408 (the annular therapeutic groove 408 is curved about ), the greater the increase in curvature of the cornea 414 caused by the redistribution of fluid and / or tissue in the epithelial layer 416 that can be accommodated in the annular therapeutic groove 408. The change in position of the annular therapeutic groove 408 is indicated on the right-hand side of the eyeglass 401. The position of the annular therapeutic groove 408 determines the position of the myopic defocus induced in the cornea 414.

[0112] The size of the adjustment area 410 can also be adjusted. Figure 8 , the change in curvature and width of the accommodation zone 410 (numbered only on the right hand side) is indicated on the left hand side of the eyeglass 401. The curvature of the accommodation zone 410 affects the curvature of the cornea 414 in the area aligned with the accommodation zone 410. The asphericity and tilt changes of the accommodation zone 410 are indicated on the right hand side of the eyeglass 401. The arrows indicate the movement of fluid and / or tissue within the epithelial layer 416 of the cornea 414. When the accommodation zone 410 is a groove, the movement of fluid and / or tissue within the cornea 414 is toward the accommodation zone 410. When the accommodation zone 410 is flatter, the movement of fluid and / or tissue within the cornea 414 is toward the annular treatment groove 408 ( Figure 8 The tilt of the adjustment region 410 may also affect the direction of movement of fluid and / or tissue in the epithelial layer 416 of the cornea 414.

[0113] Method 500 for manufacturing glasses according to the present disclosure Fig. 9 ) includes forming a lens having a rear surface in a first step 501. This step may include forming a lens body having a rear surface. The rear surface of the lens body is then modified in a subsequent step to form the rear surface of the lens according to the present disclosure. The method includes step 502: forming a correction area defined by a first segment of the rear surface. The method includes step 503: forming an annular treatment groove defined by a second segment of the rear surface. The method includes step 504: forming an accommodation area defined by a third segment of the rear surface. Step 502 of forming the correction area, step 503 of forming the annular treatment groove, and step 504 of forming the accommodation area may be performed simultaneously while forming the lens or lens body in step 501. For example, the lens may be formed in a mold that is shaped to form a rear surface of the lens having multiple curvatures, wherein the first segment of the rear surface has a curvature that defines the correction area, the second segment of the rear surface has a curvature that defines the annular treatment groove, and the third segment of the surface has a curvature that defines the accommodation area. Alternatively, step 502 of forming a corrective zone, step 503 of forming an annular treatment groove, and step 504 of forming an accommodation zone may be performed sequentially (and in any order). For example, the method may include forming the eyeglass or eyeglass body in step 501 without at least one of the annular treatment groove or the accommodation zone. In this scenario, the rear surface of the eyeglass or eyeglass body may have a radius of curvature across substantially all of its surface that is equal to the radius of curvature of the corrective zone. Step 503 of forming annular treatment groove or step 504 of forming accommodation zone may then be performed by milling to correct a segment or segments of the rear surface of the eyeglass or eyeglass body such that the segments have a radius of curvature that defines at least one of the annular treatment groove and the accommodation zone according to the present disclosure.

[0114] Method 600 of manufacturing glasses according to the present disclosure ( Fig.10) and having a back surface including a plurality of segments, each segment having a radius of curvature. A first segment of the back surface of the eyeglass defines a correction area of ​​the eyeglass, a second segment defines an annular therapeutic groove of the eyeglass, and a third segment defines an accommodation area of ​​the eyeglass. The method comprises step 601: selecting a radius of curvature of a first segment of the back surface of the eyeglass. The radius of curvature of the first segment is at least 6 mm. The method comprises step 603: selecting a radius of curvature of a second segment of the back surface of the eyeglass. The radius of curvature of the second segment is smaller than the radius of curvature of the first segment. The method comprises step 605: selecting a radius of curvature of a third segment of the back surface of the eyeglass. The radius of curvature of the third segment is in a range from 4.5 mm to 15 mm. The method 600 finally comprises step 607: manufacturing the eyeglasses so that the back surface comprises a plurality of segments having the radii of curvature selected in steps 601, 603 and 605.

[0115] While the present disclosure has been described and illustrated with reference to particular embodiments, it will be appreciated by those skilled in the art that the present disclosure lends itself to many different variations not specifically described herein.

[0116] Examples

[0117] Exemplary orthokeratology glasses according to the present disclosure will now be presented. The following examples relate to glasses adapted to induce +2D myopic defocus in the peripheral portion of the cornea. It should be understood that glasses according to the present disclosure may be designed to induce less than +2D or greater than +2D myopic defocus in the peripheral portion of the glasses. The sizes of the correction zone, annular treatment groove, and accommodation zone will be selected depending on the desired myopic defocus to be induced in the peripheral portion of the glasses, as described herein.

[0118] Example 1-Correction and treatment of low myopia

[0119] In the first example, orthokeratology lenses are designed to correct low myopia of -1.00D.

[0120] Assuming a nominal corneal power of 42D (8.03 mm) and a -1.00 DS refraction, the following parameters are calculated for each zone of the eyeglasses according to Example 1.

[0121] Zone 1 (correction zone): The required basic optical zone radius (BOZR) of the central correction zone = 42D (nominal corneal power) +-1.00 (myopia correction) +-0.75 (Jason factor) = 40.25D. This is related to the radius of curvature of 8.39mm. The diameter of the central zone is selected to be 3.36mm.

[0122] Zone 2 (annular treatment groove): To provide an add power of +2.00D, Zone 2 must have a curvature of 40.25D + 2D = 42.25D. This correlates to a radius of curvature of 7.99mm. The width of Zone 2 was selected to be 1.4mm.

[0123] Region 3 (Adjustment Region): The radius of curvature of Region 3 was selected to be 8.39 mm. The width of Region 3 was selected to be 1 mm.

[0124] Region 4 (matching region): 0.0 mm to 0.9 mm flatter than the BOZR of region 1, i.e., 9.29 mm. The width is 1.5 mm.

[0125] Region 5 (matching region): 0.0 mm to 0.9 mm flatter than the BOZR of region 1, i.e., 9.29 mm. The width is 1.5 mm.

[0126] The diameter and curvature of zones 4 and 5 (fitting zones) can vary with the decentration of the cornea. These zones serve to stabilize the lens on the cornea.

[0127] Zone 6 (edge ​​lift) has a radius of 0.1 mm. The edge lift is the outermost part of the lens that does not contact the cornea when the lens is worn.

[0128] To correct low myopia, less fluid and / or cellular tissue needs to be displaced from the central correction zone of the cornea than for higher myopia because the cornea needs less flattening. In the glasses according to Example 1, Zone 3 (the accommodation zone) has a radius of curvature that is greater than the radius of curvature of Zone 2 (the annular treatment groove). Without wishing to be bound by theory, it is believed that Zone 3 can direct displaced fluid and / or cells into the area of ​​the cornea bounded by Zone 2. This can produce a greater positive curvature and greater added power in the area of ​​the cornea bounded by Zone 2. The power in the area of ​​the cornea bounded by Zone 2 will hopefully have an added power that is at least +2D greater than the area of ​​the cornea bounded by the correction zone (Zone 1).

[0129] Example 2 - High Myopia

[0130] In the second example, orthokeratology lenses suitable for correcting and treating high myopia of -4.00D are designed.

[0131] Assuming a nominal corneal power of 42D (8.03 mm) and a -4.00 DS refraction, the following parameters are calculated for each zone of the eyeglasses according to Example 2.

[0132] Zone 1 (correction zone): Base Optic Zone Radius (BOZR) required for the central correction zone = 42D (nominal corneal power) +-4.00 (myopia correction) +-0.75 (Jerson Factor) = 37.25D. This is associated with a radius of curvature of 9.06 mm (i.e., a larger radius of curvature than that required for the low myopic zone 1 of Example 1). The diameter of the central correction zone was selected to be 3.36 mm.

[0133] Zone 2 (annular treatment groove): To provide an add power of +2.00D, Zone 2 must have a curvature of 37.25D + 2D = 39.25D. This correlates to a radius of curvature of 8.6mm. The width of Zone 2 was selected to be 1.4mm.

[0134] Region 3 (adjustment region): The radius of curvature of region 3 is selected to be 8.18 mm. The width of region 3 is selected to be 1 mm.

[0135] Region 4 (matching region): 0.0 mm to 0.9 mm flatter than the BOZR of region 1, i.e., 9.96 mm. The width is 1.5 mm.

[0136] Region 5 (matching region): 0.0 mm to 0.9 mm flatter than the BOZR of region 1, i.e., 9.96 mm. The width is 1.5 mm.

[0137] The diameter and curvature of zones 4 and 5 (fitting zones) can vary with the decentration of the cornea. These zones serve to stabilize the lens on the cornea.

[0138] Zone 6 (edge ​​lift) has a radius of 0.1 mm. The edge lift is the outermost part of the lens that does not contact the cornea when the lens is worn.

[0139] To correct high myopia, more central flattening of the cornea must occur than for low myopia. This results in a higher volume of cells and / or tissue being displaced from the central correction zone. Cells and / or tissue displacement to the peripheral regions of the cornea will typically result in a myopia treatment zone with greater than +2D due to the large volume of tissue and / or fluid that needs to be accommodated in the reverse curve. However, to control the diameter of the myopic treatment zone and limit the degree shift to the desired range of +2D, region 3 (accommodation zone) has a steeper curvature than region 2 (annular treatment groove). Without wishing to be bound by theory, it can be considered that region 3 acts as a well or reservoir for excess tissue and / or fluid that is displaced by the correction zone (region 1) and cannot be accommodated by the annular treatment groove (region 2).

[0140] Although in the present example, the curvature of the annular treatment groove and accommodation zone are modified to achieve the desired added power in the peripheral portion of the cornea, the diameter of the annular treatment groove and accommodation zone may additionally or alternatively be modified to control the amount of fluid and / or tissue contained in the peripheral portion of the cornea.

[0141] When the whole or element with known, obvious or foreseeable equivalents is mentioned in the above description, such equivalents are incorporated herein as if individually set forth. The true scope of the present disclosure should be determined with reference to the claims, which should be considered to be interpreted as covering any such equivalents. The reader should also understand that the integers or features of the present disclosure described as preferred, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. In addition, it should be understood that although such optional wholes or features may be beneficial in some embodiments of the present disclosure, they may not be expected and therefore may not exist in other embodiments.

Claims

1. A corneal reshaping contact lens for correcting and slowing the progression of myopia by reshaping portions of the cornea of ​​a myopic eye; The lens has a rear surface for contacting the portion of the cornea to be reshaped, wherein the rear surface include: a corrective zone for reducing the curvature of a central portion of the cornea, the corrective zone being defined by a first segment of the posterior surface having a radius of curvature of 6 mm or greater; an annular therapeutic groove for inducing myopic defocus in a peripheral portion of the cornea, wherein the annular therapeutic groove extends radially outward from a periphery of the correction zone and is defined by a second segment of the posterior surface having a radius of curvature that is less than the radius of curvature of the first segment, and wherein the radius of curvature of the second segment is such that the annular therapeutic groove is configured to induce at least +1D of myopic defocus in the peripheral portion of the cornea; and, An accommodation zone for adjusting the myopic defocus induced by the annular treatment groove, wherein the accommodation zone extends radially outward from the periphery of the annular treatment groove and is defined by a third section of the posterior surface having a radius of curvature in the range from 4.5 mm to 15 mm.

2. A corneal reshaping lens according to claim 1, wherein the second segment of the rear surface of the lens has a radius of curvature so that the annular treatment groove is configured to induce a myopic defocus of at least +1D but less than +12D in the peripheral portion of the cornea.

3. A corneal reshaping lens according to claim 1 or claim 2, wherein the correction area has a diameter in the range from 1 mm to 8 mm, preferably in the range from 2.5 mm to 5.5 mm.

4. A corneal reshaping lens according to any of the preceding claims, wherein at least one of the annular treatment groove and the adjustment area has a width in the range from 0.5 mm to 5.5 mm, preferably in the range from 1 mm to 2 mm.

5. Orthokeratology lens according to any one of the preceding claims, wherein the radius of curvature of the first section of the back surface of the eyeglass defining the corrective area is in the range from 6.8 mm to 15 mm; and, wherein the radius of curvature of the second section of the back surface of the eyeglass defining the annular treatment groove is in the range from 6.5 mm to 12.0 mm, as long as the radius of curvature of the second section is smaller than the radius of curvature of the first section of the back surface; and, wherein the radius of curvature of the third section of the back surface of the eyeglasses defining the accommodation zone is within the range from 4.5 mm to 15.0 mm, as long as the radius of curvature of the third section is smaller than the radius of curvature of the first section of the back surface; Optionally, the radius of curvature of the third section of the rear surface is smaller than the radius of curvature of the second section of the rear surface.

6. The orthokeratology lens according to any one of claims 1 to 4, wherein the radius of curvature of the first section of the back surface of the eyeglass defining the corrective area is in the range from 7 mm to 9.5 mm; and, wherein the radius of curvature of the second section of the rear surface of the eyeglass defining the annular therapeutic groove is in the range from 5.5 mm to 8.5 mm, as long as the radius of curvature of the second section is smaller than the radius of curvature of the first section; and, wherein the radius of curvature of the third section of the back surface of the eyeglass defining the accommodation zone is in the range of from 7.0 mm to 15.0 mm, wherein the radius of curvature of the third section is greater than the radius of curvature of the second section defining the annular treatment groove; Optionally, the radius of curvature of the adjustment region is greater than or equal to the radius of curvature of the correction region.

7. The orthokeratology lens of any of the preceding claims, wherein the correction zone is defined by a first section of the back surface of the lens that is aspherical.

8. A corneal reshaping lens according to any of the preceding claims, wherein at least one of the second section of the back surface of the lens defining the annular treatment groove or the third section of the back surface of the lens defining the adjustment area has an asymmetric profile.

9. A corneal reshaping lens according to any of the preceding claims, wherein the rear surface of the lens further includes a fitting area for stabilizing the lens to the cornea, wherein the fitting area extends radially outward from the periphery of the accommodation zone.

10. A method of manufacturing an orthokeratology contact lens according to any one of claims 1 to 9, wherein the lens is used to correct and treat myopia by reshaping a portion of the cornea of ​​a myopic eye, wherein the method comprises forming the back surface of the lens by: forming the first section of the rear surface, wherein the first section defines the corrective region of the eyeglass and has a radius of curvature of 6 mm or greater; forming a second segment of the posterior surface extending radially outward from a periphery of the corrective zone, wherein the second segment defines the annular treatment groove and has a radius of curvature that is less than the radius of curvature of the first segment, and wherein the radius of curvature of the second segment is such that the annular treatment groove is configured to induce at least +1D of myopic defocus in the peripheral portion of the cornea; and, The third section of the rear surface is formed to extend radially outward from the periphery of the annular treatment groove, wherein the third section defines the adjustment area and has a radius of curvature from 4.5 mm to 15 mm.

11. A method for manufacturing a corneal reshaping contact lens, wherein the eyeglass comprises a back surface having a plurality of segments, each segment having a radius of curvature, wherein a first segment defines a corrective region of the eyeglass, a second segment defines an annular therapeutic groove of the eyeglass, and a third segment defines an accommodation region of the eyeglass; The method includes selecting the radius of curvature of each segment by: i) selecting a radius of curvature of the first section, wherein the radius of curvature of the first section is at least 6 mm; ii) selecting a radius of curvature of the second section, wherein the radius of curvature of the second section is smaller than the radius of curvature of the first section; and, iii) selecting a radius of curvature of said third section, wherein said radius of curvature of said third section is in the range from 4.5 mm to 15 mm; and, iv) manufacturing the spectacles so that the back surface has a plurality of sections having the radii of curvature selected in steps i), ii) and iii) respectively.

12. The method of claim 11, wherein the spectacles are according to any one of claims 1 to 9.

13. A method according to any one of claims 10 to 12, wherein the method comprises first forming the glasses without at least one of the annular treatment groove or the accommodation zone and then forming the second section of the rear surface defining the annular treatment groove or the third section of the rear surface defining the accommodation zone by changing the curvature of a portion of the rear surface of the glasses using milling.

14. A method according to any one of claims 10 to 13, wherein the method comprises forming the eyeglass in a mold, wherein a surface of the mold defines at least one of: the first section of the posterior surface defining the corrective region; the second section of the posterior surface defining the annular treatment groove; and the third section of the rear surface defining the adjustment area of ​​the eyeglasses.

15. A method of treating myopia progression comprising providing a lens according to any one of claims 1 to 9 to a subject in need thereof.

16. The method of claim 15, wherein the method comprises reshaping the cornea of ​​the subject by fitting the eyeglass onto the cornea of ​​the subject.

17. The method of claim 15 or claim 16, wherein the subject is a human under 25 years of age.

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