Corneal corrective contact lenses and related methods

Abstract

The present disclosure provides an orthocorneal lens (201) and a method for manufacturing such a lens (201). The specification discloses an orthocorneal lens (210) having a correction region (206) that reduces the curvature of the central portion of the cornea, an annular treatment recess (208) that introduces proximal defocus into the peripheral portion of the cornea, and an accommodation region (210) that adjusts for the myopic defocus introduced by the annular treatment recess (208).

Description

Technical Field

[0001] The present invention relates to orthokeratology contact lenses and methods. The present invention particularly relates to contact lenses for optically correcting myopia and reforming the cornea of the eye to slow its progression, but is not limited thereto. The present invention also relates to a method of manufacturing such lenses.

Background Art

[0002] Myopia (also commonly known as "near-sightedness" or "short-sightedness" in English, but usually translated as "myopia" in Japanese) is a condition of the eye mainly caused by an elongation of the eye axis. Uncorrected myopia focuses incoming light from distant objects in front of the retina. Once the light enters the eye, it converges towards the focal plane located on the retina and then diverges beyond it, resulting in a defocus when reaching the retina. As a result, a person with myopia (myopic person) cannot focus on distant objects.

[0003] Many people use contact lenses to correct myopia. Conventional contact lenses for correcting myopia reduce the convergence of light passing through the contact lens and shift the image plane onto the retina. Distant visual acuity improves only when the refractive power of the eye + the refractive power of the lens (the "refractive power" is also called "diopter" or "power", and sometimes simply "degree", and in this specification, these are used interchangeably without distinction) is reduced with contact lenses or eyeglass lenses, or when the retina is reformed. Also, conventional contact lenses correct the mismatch between the optical refractive power and the eye axis length, but such contact lenses do not treat the abnormal eye size that is the root cause of myopia.

[0004] Decades ago, it was suggested that undercorrection—that is, bringing the focal point closer to the retina but not fully onto it—could slow or slow the progression of myopia in children or young people. However, an inevitable consequence of this approach is reduced distance visual acuity compared to distance visual acuity obtained using lenses that fully correct myopia. Furthermore, it is now considered doubtful that undercorrection is effective in controlling worsening myopia. A relatively recent approach that provides a focused image on the retina while slowing progressive eye growth involves using lenses that have both one or more regions that provide full correction of distance visual acuity and one or more regions that intentionally cause undercorrection or myopic defocus (defocusing or blurring of focus). This approach has been suggested to be able to slow or slow the worsening or progression of myopia in children or young people while also providing good distance visual acuity.

[0005] In lenses with a region that causes myopia defocus, the region that provides full correction of distance vision is commonly referred to as the base power region, and the region that causes undercorrection is commonly referred to as the myopia defocus region or add power region (because the power or refractive power expressed in diopters is positive (+) or negative (-) than the power of the distance correction base power region). The surface of the add power region (typically the anterior surface) has a smaller radius of curvature than the radius of curvature of the distance power region and therefore provides a large positive or small negative refractive power to the eye. The add power region is designed to focus light forward of the retina (i.e., in front of the retina) when the distance correction optical element is focusing light on or near the retina.

[0006] One known form of contact lens that reduces the progression of myopia is the dual-focus contact lens, marketed under the name MISIGHT (CooperVision, Inc.), as shown in Figure 1. Lens 100 has a central correction zone 101 and two other annular correction zones 102, 104. The correction zones 101, 102, 104 are distance power areas that provide a stable corrective refractive power or base power across each zone. The lens further has two annular treatment zones 106, 108. Each treatment zone 106, 108 is positioned between the two correction zones 101, 102 and 102, 104. The treatment zones 106, 108 provide add power or myopia defocus. The diameters of the corrective zones 101, 102, 104 and the treatment zones 106, 108 are clearly defined, and the refractive power is stable throughout each region. This dual-focus lens differs from bifocal or multifocal contact lenses configured to improve presbyopic vision in that it has certain optical dimensions that allow a person with accommodative power to use distance correction (i.e., base power) to see both distant and near objects. The treatment zones of the dual-focus lens with an add power also produce a myopically defocused image at both distance and near distances.

[0007] MISIGHT lenses have been shown to correct myopia and slow the progression of myopia in children (Chamberlain et al., "Optometry and Vision Science"). Optometry and Vision Science )」, 2019, 96(8):556~557pp., Chamberlain et al., "Optometry and Vision Science ( Optometry and Vision Science)" 2022, 99(3):204~212 pp. However, myopia correction and treatment are only achieved when the lens is worn. The alternative to dual-focus contact lenses for optically correcting current myopia and slowing further progression is corneal orthokeratology. Research shows that wearing corneal orthokeratology lenses overnight provides optical correction of myopia (Mountford et al., "Orthokeratology: Principles and Practice"). Orthokeratology: principles and practice )" (Butterworth-Heinemann Medical, 2004), this corneal corrective lens can also be said to be effective in slowing the progression of myopia (Cho et al., "Current Eye Research ( Current Eye Business )'', 2005, 30(1):71 / 80 pp.). Corneal corrective lenses (commonly known as "Ortho-K" lenses) correct myopia by reshaping the corneal surface and changing the curvature of the cornea in a defined area. Thus, corneal corrective lenses improve vision by bringing about physical changes in the myopic eye.

[0008] Corneal corrective contact lenses have a central region consisting of a posterior surface with a small curvature or flattened profile designed to flatten the curvature of the cornea (hereinafter sometimes referred to as "flattening"). When the lens is worn, the central corrective region exerts pressure or compressive force on the corneal epithelium, and such pressure or compressive force redistributes corneal tissue and / or fluid from the central to the peripheral portion of the cornea. This redistribution compresses the apex of the cornea, thus reducing the corneal curvature. In cases where the corneal curvature of a myopic eye is too steep to focus light onto the retina, the reduction in corneal curvature shifts the focal point of the light onto the retina, thereby correcting myopia and improving distance visual acuity. Examples of corneal corrective lenses are disclosed in U.S. Patent Nos. 6,543,897 and 6,652,095. While these specifications disclose that corneal corrective lenses can correct myopia, hyperopia, and advanced presbyopia, they do not disclose that such lenses are suitable for treating myopia or slowing its progression.

[0009] Corneal corrective lenses gradually reshape the cornea and are therefore typically worn overnight. After several hours of wear, the cornea reshapes to correct nearsightedness, and the user can remove the corneal corrective lens, for example, in the morning. After removal, the cornea maintains its new shape for several hours, and the user can focus on distant objects without needing corrective lenses. Corneal corrective lenses offer an advantage over other contact lenses in that vision remains corrected even when the lens is not being worn. During the day on the day the lens is removed, the cornea partially returns to its original shape. Therefore, the user must wear the corneal corrective lens every night to maintain the desired shape of the central corneal portion.

[0010] In addition to the corrective area, corneal corrective lenses also have an annular arch-shaped region (sometimes called a "reverse curve" or "return zone") surrounding the central corrective area of ​​the lens. This region is located on the posterior surface of the lens and is a recess corresponding to an increase in tissue volume in a region of the cornea. This increase in tissue volume in this region of the cornea results from the redistributed corneal tissue and / or fluid being directed to the peripheral portion of the cornea by the central corrective area of ​​the lens, and such an increase increases the curvature of the corneal epithelium. Thus, the annular arch-shaped region allows for the movement of corneal tissue and / or fluid away from the central region of the cornea, and thus helps to flatten the central portion of the cornea. As an unavoidable consequence of having an annular arch-shaped region, the peripheral portion of the cornea to which the tissue and fluid are redistributed is a single annular area of ​​added positive power or myopia defocus, which surrounds the central flattened region of the cornea.

[0011] While corneal corrective lenses have been found to be effective in correcting myopia in some cases, in contrast to MISIGHT lenses, the corrected area of ​​the cornea and the area of ​​positive add power created by corneal corrective lenses are not clearly defined. The correction provided by the corrective zone of corneal corrective lenses is not constant across the entire central portion of the cornea. Furthermore, providing a constant add power across the entire peripheral annular region of the cornea aligned with the annular arch region is challenging, and the add power ring created in the cornea has traditionally been considered an unavoidable result of central flattening, rather than a special design feature with controlled optical elements. Due to the limitations in controlling myopic defocus and the corrected area created in the cornea by corneal corrective lenses, their effectiveness in correcting existing myopia and slowing its future progression is currently limited.

[0012] Another problem with corneal corrective lenses is that the diameter of the corrected central portion of the cornea and the added power provided to the peripheral portion of the cornea vary in degree of correction. Generally, the greater the degree of myopia, the smaller the diameter of the central corrected portion of the cornea caused by the corrective area of ​​the lens, and the greater the ophthalmic optical add power provided to the peripheral portion of the cornea by the surrounding annular arch area. This significantly limits the degree of myopia that can be treated with conventional corneal corrective lenses and prevents the treatment from providing a controlled myopia control signal level. In contrast, the MISIGHT lens has a constant central corrective zone with a fixed diameter of 3.6 mm, even though the myopia level is treated and a well-controlled and stable myopia control treatment power is achieved. [Prior art documents] [Patent Documents]

[0013] [Patent Document 1] U.S. Patent No. 6,652,095 [Patent Document 2] U.S. Patent No. 6,543,897 [Non-patent literature]

[0014] [Non-Patent Document 1] Chamberlain et al., "Optometry and Vision Science," 2019, 96(8): 556-557. [Non-Patent Document 2] Chamberlain et al., "Optometry and Vision Science," 2022, 99(3): pp. 204-212. [Non-Patent Document 3] Mountford et al., "Orthokeratology: Principles and Practice," Butterworth-Heinemann Medica, 2004. [Non-Patent Document 4] Cho et al., "Current Eye Research," 2005, 30(1):71 / 80. [Overview of the project] [Problems that the invention aims to solve]

[0015] The present invention seeks to provide a corneal corrective lens that provides control over the diameter of the corrected central portion of the cornea, even though the level of myopia has been treated. Such a lens can further provide more consistent refractive power across the entire corrected central region of the cornea. Additionally or alternatively, such a lens can provide a clearly defined area of ​​myopic defocus in the treated cornea. [Means for solving the problem]

[0016] According to a first aspect, the present invention provides a corneal corrective contact lens that corrects myopia and slows its progression, such a lens as described in claim 1.

[0017] The present invention further provides, according to a second aspect, a method for manufacturing a corneal corrective contact lens, which is described in claim 10.

[0018] In a third aspect, the present invention provides a method for manufacturing a corneal corrective contact lens, such method being described in claim 11.

[0019] The present invention further provides a method for treating the progression of myopia, including the step of providing a lens according to the first aspect to a patient who needs the lens, and such a method is described in claim 15.

[0020] Optional but preferred features are described in the dependent claims.

[0021] Of course, it will be recognized that features described in connection with one aspect of the present disclosure can be incorporated into other aspects of the present disclosure. For example, the method for preparing the corneal corrective contact lens of the present disclosure can incorporate any of the features described for the corneal corrective contact lens of the present invention, and vice versa.

[0022] Next, embodiments of the present invention will be described with reference to the accompanying schematic drawings, which are merely illustrative.

Brief Description of the Drawings

[0023] [Figure 1] It is a plan view of a prior art dual focus lens 100. [Figure 2A] It is a cross-sectional view of the lens 201 of the present invention taken along the line A-A' of FIG. 2B, showing that the lens 201 is suitable for treating or slowing down the progression of myopia in relatively high myopia. [Figure 2B] It is a plan view of the lens 201 shown in FIG. 2A, showing a state where the boundary of each concentric region coincides with the boundary of the lens region determined by the change in the curvature of the rear surface 202 of the lens. [Figure 3A] It is a cross-sectional view of the lens 301 of the present invention taken along the line A-A' of FIG. 3B, showing that this lens is suitable for treating or slowing down the progression of myopia in relatively low myopia. [Figure 3B] It is a plan view of the lens 301 shown in FIG. 3A, showing a state where the boundary of each concentric region coincides with the boundary of the lens region determined by the change in the curvature of the rear surface 302 of the lens. [Figure 4A]This is a cross-sectional view of the lens 401 of the present invention in use, where the lens 401 is positioned on the surface of the cornea 414. For clarity, the accommodative region of the lens is not shown, and the arrows indicate the pressure force applied to the cornea 414 by the central corrective region 406 of the lens 401 and the resulting fluid and / or tissue flow from the central portion of the cornea 414 to the peripheral portion. [Figure 4B] This is a cross-sectional view of the surface profile of the cornea 414 before and after treatment. The dashed line shows the surface profile of the cornea 414 before treatment with lens 401 in Figure 4A, and the solid line shows the region of the cornea 414 with the modified surface profile following treatment with lens 401. The figure shows that the surface profile of the cornea 414 after treatment is flattened and has a low curvature in the central part and raised and high curvature in the peripheral part, compared to the surface profile of the cornea 414 before treatment. [Figure 5] Figure 4A is a cross-sectional view of lens 401, illustrating the regions of lens 401 (corrective region 406, annular treatment recess 408, and fitting region 412), and showing that the dimensions (width, curvature, depth, asymmetry, and symmetry) of these illustrated regions control the movement of corneal tissue and fluid, thus being adjustable to induce a specific profile in the cornea to be treated as shown. For clarity, the accommodative region of lens 401 is not shown, and arrows indicate the movement of fluid and / or tissue within the cornea 414. [Figure 6] Figure 4A is a cross-sectional view of lens 401 showing the dimensions of the adjustable annular therapeutic recess 408. For clarity, the accommodative region of lens 401 is not shown. The left side of lens 401 shows the change in the width of the annular therapeutic recess 408, and the right side of the lens shows the change in the inclination or asphericity of the annular therapeutic recess 408. Arrows indicate the movement of fluid and / or tissue within the cornea 414. [Figure 7]Figure 4A is a cross-sectional view of lens 401 showing different dimensions of the adjustable annular therapeutic recess 408, and for clarity, the adjustment area of ​​lens 401 is not shown, the left side of lens 401 shows the change in curvature and inclination of the annular therapeutic recess 408, the right side of lens 401 shows the change in position of the annular therapeutic recess 408, and arrows indicate the movement of fluid and / or tissue within the cornea 414. [Figure 8] Figure 4A is a cross-sectional view of lens 401 showing the dimensions of the adjustable adjustment region 410. The left side of lens 401 shows the change in curvature and width of the adjustment region 410, and the right side of lens 401 shows the change in inclination or asphericity and symmetry of the adjustment region 410, with arrows indicating the movement of fluid and / or tissue within the cornea. [Figure 9] This figure shows a method 500 for manufacturing a lens according to the present invention. [Figure 10] This figure shows another method 600 for manufacturing the lens of the present invention. [Modes for carrying out the invention]

[0024] According to a first aspect of this disclosure, a corneal corrective contact lens is disclosed. The corneal corrective contact lens is for treating or slowing the progression of myopia by reshaping a portion of the myopic cornea. The lens has a posterior surface that contacts the portion of the cornea to be reshaped. The posterior surface of the lens has a corrective region that reduces the curvature of the central portion of the cornea. The corrective region is comprised of a first segment of the posterior surface with a radius of curvature greater than 6 mm. The posterior surface of the lens further has an annular corrective recess that causes myopic defocus in the peripheral portion of the cornea. The annular corrective recess is comprised of a second segment of the posterior surface that extends radially outward from the periphery of the corrective region and has a radius of curvature smaller than that of the first segment, the radius of curvature of the second segment being configured such that the annular corrective recess causes myopic defocus of at least +1D in the peripheral portion of the cornea. The posterior surface of the lens has an accommodative region that adjusts the myopic defocus caused by the annular corrective recess. The adjustment region extends radially outward from the periphery of the annular treatment recess and is composed of a third section of the posterior surface having a radius of curvature ranging from 4.5 mm to 15 mm.

[0025] In a second aspect, a method is disclosed for manufacturing a corneal corrective contact lens that treats or slows the progression of myopia by reshaping a portion of the myopic cornea. The corneal corrective contact lens is preferably a lens according to the first aspect of this disclosure. The method includes the step of forming a posterior surface of the lens that contacts the portion of the cornea to be reshaped. The method includes the step of forming a first segment of the posterior surface, the first segment constituting a corrective area of ​​the contact lens and also having a radius of curvature of 6 mm or more. The method further includes the step of forming a second segment of the posterior surface extending radially outward from the periphery of the corrective area. The second segment constituting an annular treatment recess and also having a radius of curvature smaller than that of the first segment. The radius of curvature of the second segment is such that the annular treatment recess causes at least +1D of myopic defocus in the peripheral portion of the cornea. The method further includes the step of forming a third segment of the posterior surface extending radially outward from the periphery of the annular treatment recess. The third section constitutes the adjustment area and also has a radius of curvature ranging from 4.5 mm to 15 mm. The first, second, and third sections of the rear surface of the lens may be formed sequentially or simultaneously by the method disclosed herein.

[0026] In this specification, "contact lens" or simply "lens" refers to an occulmic lens that can be worn on the anterior surface of the eye. Corneal corrective contact lenses are a type of contact lens, and their properties and characteristics are described herein. As is recognized, contact lenses provide clinically acceptable inocular movement and do not become immobile or stuck to a person's eye (one or both). Contact lenses take the form of a corneal lens (a lens that rests on the cornea of ​​the eye).

[0027] According to this disclosure, the lens is a corneal corrective contact lens (also known as an "ortho-K lens"). To be understood, when the “lens” of this invention is used, it refers to a corneal corrective contact lens unless otherwise specified. Traditional contact lenses correct myopia by reducing the degree of convergence of incoming light from distant objects before it reaches the eye, thereby shifting the focal point onto the retina. Thus, traditional contact lenses must be worn on the cornea to improve vision. In contrast, the corneal corrective contact lenses of this disclosure alter the optical properties of the eye itself by gradually changing or reforming the surface profile of the patient’s cornea during continued wear. This reformation of the lens surface profile allows for temporary optical correction for myopia.

[0028] The corneal corrective contact lenses disclosed, when worn, constantly apply pressure to a selected area of ​​the cornea, reshaping the cornea to a desired surface profile. In particular, corneal corrective contact lenses are placed on the cornea and primarily reshape the corneal epithelium by altering the distribution of fluids and / or tissues within the epithelium. As can be understood, when we say fluids and / or tissues, this refers to any organic or physiological substances in the corneal epithelium that can be moved by the compressive force applied to the surface of the cornea. For example, fluids in the corneal epithelium typically include aqueous solutions of water or solutes found in the cornea, which may further include dispersions of organic substances typically found in the cornea dissolved in aqueous solutions. Tissues may refer to cells or groups of cells typically found in the cornea. The corneal corrective contact lenses of this disclosure can reshape the cornea of ​​the eye, that is, to reshape the cornea with a radius of curvature that focuses incoming light from distant objects before it reaches the eye, and to reshape the cornea with a radius of curvature that reduces the degree of convergence of incoming light so that it focuses on the retina. Mechanisms as means for redistributing corneal fluid and / or tissue are disclosed herein. The reshaped surface profile of the cornea can be retained even after the corneal corrective contact lens is removed from contact with the cornea of ​​the eye. The reshaped surface profile of the cornea can be retained for a long period of time even after the lens is removed from contact with the cornea of ​​the eye, and as a result, distance visual acuity is retained for several hours, up to 5 hours, up to 8 hours, up to 12 hours, or up to 16 hours, or all day or over several days. Thus, the optical correction obtained by the corneal corrective contact lens is maintained in the cornea even after the lens is removed.

[0029] The corneal corrective contact lenses disclosed herein are for correcting and treating myopia. As understood, myopia correction means altering the optical properties of the eye to reduce or eliminate the degree of myopia and to achieve adequate visual acuity without the need for corrective devices, such as traditional contact lenses or spectacle lenses. For example, an eye with a myopia of -0.25D to -15D can exhibit a myopia reduction of at least 0.5D, preferably at least 0.75D, after wearing the lenses of the present invention. Perhaps, wearing the corneal corrective contact lenses every night for a week will achieve a correction of myopic refractive error to the extent that traditional corrective devices, such as contact lenses or spectacle lenses, are no longer needed. Preferably, as a result of myopia correction, the eye is no longer myopic, and therefore external correction for visual acuity (e.g., wearing spectacle lenses or contact lenses) is no longer necessary for distance visual acuity. Myopia can be corrected by the lens reducing the curvature of at least the central portion of the cornea. This can be achieved by corneal corrective contact lenses according to the mechanism described herein. As is understood, myopia correction in the central portion of the cornea is necessary for correcting distance visual acuity. However, the peripheral portion of the cornea remains uncorrected, and in fact, its myopia is increased ("myopia defocus"), so it does not interfere with distance visual acuity. For example, the corneal corrective contact lenses according to this disclosure can correct myopia with respect to the central portion of the cornea, while undercorrecting myopia, or adding positive refractive power to the peripheral portion of the cornea. Such undercorrection or addition of positive power to the peripheral portion can be described as introducing myopia defocus into the eye.

[0030] As is understood, the treatment of myopia means slowing the progression of myopia. As a result of the treatment of myopia, the progression of myopia may stop or reverse. This may be particularly beneficial for children, where myopia typically worsens with age. It may also be possible to prevent the development of myopia in patients at risk of developing it by using corneal corrective contact lenses. While not bound by theory, it is thought that the myopia defocus introduced into the peripheral part of the cornea by the corneal corrective contact lenses disclosed herein plays a role in slowing the progression of myopia or preventing its development. The annular corrective recess of the corneal corrective contact lenses disclosed herein can introduce myopia defocus into the cornea by the mechanism disclosed herein.

[0031] The corneal corrective contact lenses disclosed are preferably rigid (hard) contact lenses made of a hard material. The lenses are preferably gas-permeable hard contact lenses. The corneal corrective contact lenses are preferably made of polymethyl methacrylate (PMMA), or copolymers of fluoromethacrylate or siloxanyl styrene, copolymers of fluorosilicone acrylate compounds, or copolymers of silicone methacrylate compounds or fluorine methacrylate compounds. Suitable lens materials include materials having the following US generic names (USAN): tisifocn A, tolofocon A, paflufocn A, paflufocn B, and paflufocn C. As can be understood, hard lenses are particularly effective in redistributing corneal fluids and / or tissues in the corneal epithelial layer, because the hard structure can exert sufficient compressive force on the corneal surface to push fluids and / or tissues from one area of ​​the cornea to another.

[0032] The term "lens body" refers to the bulk of the lens, and in particular, may be used to refer to the division of the lens bounded by the front and rear surfaces. The lens body is preferably formed from a number of lens layers. The term "lens layer" refers to a region of lens material that forms at least one division of the lens body. If there are multiple lens layers, each lens layer has a thickness less than the thickness of the lens body. Optionally, the lens body consists of lens layers attached to at least one other layer. For example, multiple layers, e.g., at least two or at least three layers, may be laminated to form the lens body. If there are multiple lens layers, the lens layers can be made of the same or different materials. Optionally, at least two of the lens layers may be made of the same material, and at least one lens layer may be made of a different material. If the lens body has multiple lens layers, there are probably indistinguishable boundaries between the layers. For example, the lens body can be formed by curing a bulk material to form a first layer, then layering another material on top of the first layer and curing it to form a second layer. If the first and second layers are made of different materials, it will be clear that there is a boundary where the chemical composition of the materials changes between one layer and the other. If the first and second layers are made of the same material, there may be different physical properties between these layers, for example, different optical properties or degrees of crystallinity at the boundaries between the lens layers. As is understood, when a lens is made of two or more lens layers, the rear surface of the lens refers to the rear surface of the bottommost layer, i.e., the layer that comes into contact with the eye when the lens is worn. The front surface of the lens should be understood as the front surface of the topmost layer, i.e., the layer that is furthest from the surface of the eye when the lens is worn, if the lens is made of multiple layers. The lens body may be made of a single lens layer. As is understood, when the lens body is made of a single lens layer, the bulk material forming the lens body is uniform, and therefore there will be no indistinguishable boundaries between the different regions of the bulk material forming the lens body.If the lens body is made of a single lens layer, the lens layer forms the entire lens body, and in this case, the terms lens layer and lens body can be used interchangeably. Presumably, a single lens layer forms the entire lens.

[0033] Corneal corrective contact lenses should ideally have a substantially circular shape when viewed in plan view, with a diameter ranging from 8mm to 25mm. Optionally, the lens diameter may also range from 8mm to 15mm.

[0034] The corneal reshaping contact lens according to this disclosure has an anterior surface and a posterior surface opposite to it. The anterior surface faces away from the eye when the contact lens is placed on the eye, and the anterior surface is preferably convex overall. The posterior surface faces towards the eye when the contact lens is placed on the eye. The posterior surface is preferably concave overall. The posterior surface of the lens is in contact with the cornea of ​​the eye. As understood, at least a major portion of the posterior surface, for example, at least 50%, at least 75%, or at least 90% of the posterior surface, is preferably in contact with the surface of the cornea when the lens is worn. The contact between the posterior surface of the lens and the cornea allows the lens to reshape the surface of the cornea as described herein.

[0035] The posterior surface of a corneal corrective lens has a corrective region. The corrective region is a region on the posterior surface of the lens that, when the lens is worn, reduces the curvature of the central portion of the corneal corrective lens. The lens is configured such that, when the lens is worn, the corrective region covers the pupil of the eye. Preferably, the corrective region is located in the center of the lens around the central axis when the lens is viewed in plan view. The corrective region aligns with the central portion of the cornea to be treated. Preferably, the corrective region is substantially circular when viewed in plan view.

[0036] The corrective region is comprised of a first segment of the posterior surface having a radius of curvature greater than that of the central portion of the cornea. As can be understood, the larger the radius of curvature, the flatter the corrective region becomes.

[0037] When the lens is worn, the corrective area contacts the apex of the cornea, and the central area has a flatter or less curvilinear profile than the apex of the cornea, so as a result, the central portion of the cornea is flattened by compression. Thus, the corrective area is configured to correct distance vision in myopic eyes by flattening or reducing the curvature of the central portion of the treated cornea. Although not bound by theory, it is thought that the corrective area reduces the curvature of the central portion of the cornea by pushing epithelial fluid and / or tissue from the central portion of the cornea to the peripheral portion. When a corneal corrective lens is worn, the central portion of the cornea is at least partially shaped with respect to at least a portion of the corrective area of ​​the lens, or affected by the profile of such portion. Thus, the topology of the central portion of the cornea is flatter after lens insertion than before lens insertion.

[0038] To correct refractive errors in myopia, the central portion of the cornea needs to be flattened or made to have a smaller curvature. The minimum radius of curvature required for the corrective area of ​​the lens should be close to the radius of curvature required to correct low myopia, for example, -0.25D. High myopia requires a relatively high degree of flattening, and thus the corrective area must have a larger radius of curvature than the corrective area required for low myopia. Thus, the maximum radius of curvature of the corrective area should be close to the radius of curvature required to correct high myopia, for example, -15D.

[0039] The corrective area is comprised of a first section of the posterior surface of the lens having a radius of curvature of 6 mm or more, for example, 7 mm or more, or 8 mm or more. The corrective area is preferably comprised of a first section of the posterior surface having a radius of curvature of less than 15 mm, less than 12 mm, less than 12 mm, or 10 mm or more. The radius of curvature of the corrective area is preferably in the range of 6 mm to 15 mm, 6 mm to 12 mm, 6 mm to 10 mm, 6 mm to 9.5 mm, 7 mm to 9.5 mm, 7 mm to 9 mm, 6 mm to 8.5 mm, 8.8 mm to 9.3 mm, 6 mm to 6.8 mm, or 6 mm to 9.9 mm. Optionally, the radius of curvature of the corrective area is preferably in the range of 6 mm to 9.9 mm. When treating relatively low myopia, such as -1.0D, it may be advantageous to provide a corrective area with a curvature radius in the range of 7mm to 9.5mm. When treating relatively high myopia, such as -4.0D or higher, it may be advantageous to provide a corrective area composed of a portion of the posterior surface of the lens with a curvature radius in the range of 6.8mm to 15mm.

[0040] Presumably, the corrective area provides additional correction beyond what is necessary to treat myopia. This overcorrection takes into account the gradual reversion of the corneal profile to its untreated state during the day when the lens is no longer worn. For example, an overcorrection of about -0.75D is preferable to introduce by the corrective area to allow for a partial reversion of the central portion of the cornea to its natural, more curvatured state when the lens is not worn. This overcorrection is called the Jessen factor. The overcorrection should be greater than -0.5D, greater than -1D, or greater than 2D. Presumably, it could be said that the overcorrection extends the period during which the cornea maintains a focused distance when the lens is not worn. Also, the overcorrection increases the amount of fluid and / or cells moving in the peripheral portion of the cornea, because the central portion of the cornea becomes flatter (flattened). This can help control the amount of treatment defocus by the annular treatment recess, because there is a large amount of fluid and / or cells that should be redistributed within the cornea.

[0041] The orthodontic area may have a diameter greater than 1 mm, greater than 2 mm, or greater than 3 mm. The orthodontic area may have a diameter less than 8 mm, less than 6 mm, less than 5 mm, or less than 4 mm. The orthodontic area may have a diameter in the range of 1 mm to 8 mm, 2 mm to 6 mm, more preferably 2.5 mm to 5.5 mm, and most preferably 3 mm to 4 mm. In a preferred embodiment, the orthodontic area has a diameter of about 3 mm, for example, 3.36 mm.

[0042] The corrective area may be comprised of a first segment of the posterior surface of a spherical lens. In a variation, the corrective area may be comprised of a first segment of the posterior surface of an aspherical lens. As can be understood, an aspherical profile is one in which the radius of curvature is not constant across the entire segment of the posterior surface corresponding to the diameter of the corrective area. For example, the radius of curvature at the center of the corrective area may be greater than the radius of curvature at either end or both ends of the corrective area. In a variation, the radius of curvature at the center of the corrective area may be smaller than the radius of curvature at either end or both ends of the corrective area. The radius of curvature may increase at the edge of the corrective area. In a variation, the radius of curvature may decrease towards the edge of the corrective area. An aspherical corrective area may be advantageous in achieving a more consistent base power across the entire central portion of the cornea, because the degree of flattening can be reduced by the radial distance from the apex of the cornea. Optionally, the corrective area may be comprised of a first segment of the posterior surface that has been made to treat astigmatism. For example, the profile of the posterior surface of the orthodontic area should ideally be toric.

[0043] The posterior surface of the lens further has an annular treatment recess extending radially outward from the periphery of the corrective area. The lens is configured such that, when the lens is in use, the annular treatment recess, together with the corrective area, aligns with the pupil of the eye. When the lens is viewed in plan, the central corrective area is centered on the central axis of the lens, and the annular treatment recess surrounds the central corrective area. When the lens is worn, the annular treatment recess aligns with the peripheral portion of the cornea to be treated. Preferably, the annular treatment recess is substantially circular when viewed in plan.

[0044] The annular treatment recess introduces myopic defocus into the peripheral portion of the cornea, and this annular treatment recess is composed of a second section of the posterior surface having a smaller radius of curvature than the first section of the posterior surface (i.e., the corrective region). Because the radius of curvature of the annular treatment recess is smaller than the radius of curvature of the corrective region, the annular treatment recess has a greater curvature, and this annular treatment recess provides an add to the treated cornea. As can be understood, the shorter the radius of curvature of the second section of the posterior portion of the lens, the greater the curvature of the annular treatment recess and the greater the add. The annular treatment recess is formed on the concave posterior surface of the lens.

[0045] When the lens is in use, the annular therapeutic recess allows for an increase in the thickness and curvature of the peripheral portion of the cornea. This increase in thickness / curvature results from increased pressure within the central region of the cornea (caused by the corrective region of the lens), which in turn causes a redistribution of fluid and / or tissue to the peripheral portion. As can be understood, the corneal surface exhibits a profile influenced by the profile of the posterior surface of the lens, since the corneal surface is compressed to at least partially conform to the shape of the posterior surface of the lens. Thus, the peripheral portion of the cornea aligned with the annular therapeutic recess is shaped by the annular therapeutic recess when the lens is worn, and this peripheral portion will have an added (convex) curvature. The shaped peripheral portion of the cornea will add positive refractive power or myopia defocus to the cornea. The annular therapeutic recess controls the shape of the peripheral portion of the cornea that provides myopia defocus in the treated eye. As should be understood, the shape of the peripheral portion of the cornea does not necessarily coincide with the shape of the annular treatment recess; for example, the peripheral portion of the cornea can only partially fill the annular treatment recess when a lens is worn.

[0046] The corrective region of the lens provides refractive power to the central portion of the cornea by altering the central corneal curvature and also by flattening the region. The annular treatment recess results in undercorrection of distance vision or intentionally introduces myopic defocus into the cornea. The radius of curvature of the second segment of the peripheral portion of the lens is greater than the refractive power resulting from the flattened central portion of the cornea, introducing at least +1D of myopic defocus into the peripheral portion of the treated cornea. As is understood, diopters, or "D," are a unit of measurement for the refractive power of a lens and are a common term in the art. The add power provided to the peripheral portion of the cornea by the annular treatment recess is greater than the refractive power resulting from the flattened central portion of the cornea, and is preferably 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. The add-on provided to the peripheral portion of the cornea by the annular treatment recess is preferably less than +12.0D, less than +8.0D, or less than +6.0D. For example, the add-on provided to the peripheral portion of the cornea by the annular treatment recess is preferably at least +1.0D but less than 12.0D. This is achieved by controlling the curvature of the annular treatment recess. The annular treatment recess can also help create a uniform corrected area in the central portion of the cornea by accepting at least a fraction of the fluid and / or tissue displaced from the central portion of the cornea. As disclosed herein, the width, depth, curvature, and location of the annular treatment recess may affect the amount of redistributed fluid and / or tissue accepted into the peripheral portion of the cornea.

[0047] The annular treatment recess introduces myopia defocus to the peripheral cornea by reducing the degree of flattening of the corneal curvature, allowing the corneal curvature to remain non-flattened, or increasing the curvature of the peripheral cornea located beneath the annular treatment recess when the lens is worn. The radius of curvature of the annular treatment recess is selected according to the degree of flattening or increase in curvature required for the peripheral cornea. The peripheral cornea is not fully corrected in order to achieve distance visual acuity. Thus, intentional undercorrection or myopia defocus is introduced to the peripheral cornea. Although not bound by theory, myopia defocus introduced to the peripheral cornea is thought to contribute to the delay of myopia progression. The dimensions of the annular treatment recess should be modified to control the amount of myopia defocus introduced and the location of the cornea where the defocus should be introduced.

[0048] In the annular treatment recess, the lens has a residual portion of lens material in the direction of the lens thickness that has a recess and a surface that constitutes the closed end of the recess. The surface that constitutes the closed end of the recess is a second segment of the rear surface of the lens. The second segment of the rear surface of the lens has a curvature that determines the curvature of the recess.

[0049] The depth of a recess is defined as the distance from the open end of the recess (i.e., the rear surface that would exist if the recess were not present) to the closed end of the recess (i.e., the surface of the lens material that constitutes the end of the recess). One or more recesses are preferably 3% to less than 100% of the thickness of the remaining portion of the lens material. For example, recesses may be 10% to 80%, 20% to 60%, or 30% to 50% of the thickness of the remaining portion.

[0050] The radius of curvature of the second section of the posterior surface of the lens constituting the annular treatment recess is preferably in the range of 5.5 mm to 12 mm, for example, in the range of 6.5 mm to 12.0 mm, 7.5 mm to 9.0 mm, 8.0 mm to 9.0 mm, 5.5 mm to 8.5 mm, 7.5 mm to 8.5 mm, or 8.5 mm to 9.5 mm. The curvature of the second section of the posterior surface constituting the annular treatment recess is preferably selected according to the curvature of the orthodontic area. For example, if the radius of curvature of the first section of the posterior surface of the lens constituting the orthodontic area is in the range of 8.0 mm to 8.5 mm, the radius of curvature of the second section of the posterior surface constituting the annular treatment recess is preferably in the range of 7.7 mm to 8.2 mm. If the radius of curvature of the first segment of the posterior surface of the lens constituting the corrective area is in the range of 8.8 mm to 9.3 mm, then the radius of curvature of the second segment of the posterior surface constituting the annular treatment recess is preferably in the range of 8.3 mm to 8.8 mm. Presumably, the flatter the corrective area (the smaller the curvature), the greater the amount of corneal fluid and / or tissue displaced by the lens, requiring an annular treatment recess with a higher curvature. As a variation, in relatively high myopia, the corrective area may be flatter than in low myopia, but since the curvature of the surface profile of the peripheral portion before corneal treatment is already high, the annular treatment recess may preferably have a radius of curvature equal to or smaller than the radius of curvature of the peripheral portion before corneal treatment, with the purpose of retaining or flattening the peripheral portion to obtain the desired myopia defocus. The radius of curvature of the second segment of the posterior surface of the lens constituting the annular treatment recess is smaller than the radius of curvature of the first segment of the posterior surface of the lens constituting the orthodontic area.

[0051] The annular treatment recess should have a width ranging from 0.5 mm to 5.5 mm, from 1 mm to 4 mm, for example, from 1 mm to 2 mm. As can be understood, since the treatment recess is annular, the width should be determined by the distance between the circumference of the inner edge of the recess and the circumference of the outer edge of the recess in the direction of movement from the center of the lens to the edge of the lens (viewed in a plan view of the lens).

[0052] The annular treatment recess may be symmetrical or asymmetrical; that is, the recess is composed of a second segment of the posterior surface of the lens having either a symmetrical or asymmetrical profile. The annular treatment recess is preferably composed of a second segment of the posterior surface of the lens that is spherical. As a variation, the annular treatment recess may be composed of a second segment of the posterior surface of the lens that is aspherical. The shape of the recess can impart a specific optical refractive power to the portion of the cornea aligned with the recess of the lens. The annular treatment recess is preferably asymmetrical such that a portion of the annular treatment recess closest to the corrective area has a smaller radius of curvature than a portion of the annular treatment recess further from the corrective area. As understood, such an asymmetrical profile inclines the annular treatment recess toward the corrective area. As a variation, the annular treatment recess may be asymmetrical such that a portion of the annular treatment recess closest to the corrective area has a larger radius of curvature than a portion of the annular treatment recess further from the corrective area. As understood, such an asymmetrical profile inclines the annular treatment recess toward the corrective area. The inclination of the annular treatment recess can help direct tissue and / or fluid toward or away from the central portion of the cornea that coincides with the corrective area. The radius of curvature of the annular treatment recess may depend on the radius of curvature of the corrective area.

[0053] The lens further has an accommodative region radially outward from the periphery of the annular therapeutic recess. Thus, as can be understood, the accommodative region is also annular or annular as a whole when viewed in plan, and the center of this therapeutic region is located on the central axis of the lens. The accommodative region modulates myopic defocus introduced into the peripheral portion of the cornea by the annular therapeutic recess or central corrective region. The accommodative region modulates the degree of increase in corneal curvature in the peripheral portion resulting from increased pressure within the cornea caused by the redistribution of fluid and / or tissue toward the peripheral portion, and also controls the movement of fluid and / or tissue from the distant periphery of the cornea to the peripheral portion of the cornea aligned with the annular therapeutic recess, as described herein. The accommodative region can additionally or alternatively help achieve a central portion of the cornea with uniform refractive power across the entire diameter of the cornea. For example, the accommodative region can act as an additional recess that allows for the increase in corneal curvature in the peripheral portion resulting from increased pressure within the cornea caused by the redistribution of fluid and / or tissue toward the peripheral portion. The accommodative zone should ideally be located outside the optical zone so as not to interfere with the user's vision. Presumably, the accommodative zone should not overlap with the pupil of the eye when the lens is in use.

[0054] The accommodative region has a radius of curvature determined by a third division of the rear surface of the lens, and the third division has a refractive power ranging from a value 12 diopters greater than the radius of curvature of the corrective region to a value 12 diopters less than the radius of curvature of the corrective region. For example, the third division of the rear surface of the lens constituting the accommodative region may have a curvature that provides a refractive power ranging from a value 0 diopters greater than the radius of curvature of the corrective region to a value 12 diopters greater, from a value 0 diopters greater than the radius of curvature of the corrective region to a value 8 diopters greater, or from a value 0 diopters greater than the radius of curvature of the corrective region to a value 4 diopters greater. As a variation, the third segment of the rear surface of the lens constituting the accommodative region may have a curvature that provides refractive power in the range of 0 diopters less than the radius of curvature of the corrective region to 12 diopters less, in the range of 0 diopters less than the radius of curvature of the corrective region to 8 diopters less, or in the range of 0 diopters less than the radius of curvature of the corrective region to 4 diopters less.

[0055] The radius of curvature of the third segment of the posterior surface of the lens constituting the accommodative region is preferably in the range of 4.5 mm to 15 mm, for example, in the range of 4.5 mm to 12 mm, in the range of 7 mm to 15 mm, or in the range of 7 mm to 9 mm. The accommodative region is preferably having a width in the range of 0.5 mm to 5.5 mm and in the range of 1 mm to 4 mm, for example, this width is preferably in the range of 1 mm to 2 mm. Perhaps the radius of curvature of the third segment is equal to the radius of curvature of the second segment constituting the corrective region. Perhaps the radius of curvature of the third segment is larger than the radius of curvature of the second segment constituting the corrective region, for example, by at least 0.9 mm. Perhaps the radius of curvature of the third segment is smaller than the radius of curvature of the second segment constituting the corrective region, for example, by at least 0.9 mm. As can be understood, since the adjustment region is annular, its width can be defined as the distance between the circumference of the inner edge of the adjustment region and the circumference of the outer edge of the adjustment region in the direction of movement from the center of the lens to the edge of the lens (when viewing the lens in a plan view).

[0056] The accommodative region may be asymmetrical, i.e., it may be composed of a third segment of the posterior surface of a lens having a symmetrical profile. The accommodative region may be asymmetrical, i.e., it may be composed of a third segment of the posterior surface of a lens having an asymmetrical profile. The accommodative region may be composed of a third segment of the posterior surface of a spherical lens. As a variation, the accommodative region may be composed of a third segment of the posterior surface of an aspherical lens. The shape of the accommodative region can impart a specific optical refractive power to the lens. The accommodative region may be asymmetrical such that a portion of the accommodative region closest to the annular treatment recess has a smaller radius of curvature than a portion of the accommodative region further away from the annular treatment recess. As can be understood, such an asymmetrical profile inclins the accommodative region toward the annular treatment recess and the corrective region. As a variation, the accommodative region may be asymmetrical such that a portion of the accommodative region closest to the annular treatment recess has a larger radius of curvature than a portion of the accommodative region further away from the annular treatment recess. As can be understood, such an asymmetrical profile tilts the accommodative region away from the annular treatment recess and the corrective region. This can help direct tissue and / or fluids toward or away from the portion of the cornea aligned with the annular treatment recess, as needed. The radius of curvature of the accommodative region may depend on the radius of curvature of the corrective region.

[0057] In some embodiments, the radius of curvature of the accommodative region is smaller than the radius of curvature of the corrective region. In such embodiments, the accommodative region can act to accommodate fluid and / or tissue displaced by the corrective region, which is not accepted by the annular corrective recess of the lens. This is particularly advantageous when the degree of myopia being corrected is relatively high, for example, -4.00D. In such embodiments, a relatively large degree of flattening of the central portion of the cornea is required, and thus a large amount of tissue and / or fluid is displaced by the corrective region of the lens. The volume of displaced tissue and / or fluid is preferably larger than the volume required to produce the desired myopic defocus in the peripheral portion of the cornea. It is desirable to avoid the excessively displaced tissue and / or fluid entering the peripheral portion of the cornea, as this would introduce additional refractive power to that region of the cornea in addition to the desired refractive power. To help achieve a desired amount of myopia defocus in the peripheral portion of the cornea within a clearly defined area, the accommodative region may serve as a reservoir for receiving excess displaced tissue and / or fluid. In this case, the accommodative region is a region of the lens from which the curvature of the cornea can be enlarged. Thus, the accommodative region in such embodiments can be considered a second recess, which may have any of the features disclosed in relation to the annular therapeutic recess. The accommodative region in such embodiments can introduce a second myopia defocus into the cornea.

[0058] Optionally, the corneal reshaping lens has a corrective region comprised of a first segment of the posterior surface of the lens with a radius of curvature ranging from 6.8 mm to 15.0 mm, and the radius of curvature of a third segment of the posterior surface comprising the accommodative region is in the range of 4.5 mm to 15 mm, and this curvature is smaller than the curvature of the first segment of the posterior surface comprising the corrective region. Optionally, the curvature of a second segment of the posterior surface of the lens comprising the annular treatment recess is in the range of 6.5 mm to 12.0 mm, provided that this radius of curvature is smaller than the radius of curvature of the corrective region. Optionally, the radius of curvature of a third segment of the posterior surface of the lens comprising the accommodative region is smaller than the radius of curvature of a second segment comprising the annular treatment recess. For example, if the radius of curvature of the first section of the posterior surface of the lens constituting the corrective area is in the range of 8.8 mm to 9.3 mm, then the radius of curvature of the second section of the posterior surface constituting the annular treatment recess is preferably in the range of 8.3 mm to 8.8 mm, and the radius of curvature of the third section of the posterior surface constituting the accommodative area is preferably in the range of 7.9 mm to 8.4 mm. Such lenses are said to be particularly effective in correcting and treating high myopia, for example, myopia of at least -4.0 D.

[0059] In some embodiments, the radius of curvature of the accommodative region is greater than or equal to the radius of curvature of the corrective region. In such embodiments, the accommodative region can act to direct fluid and / or tissue displaced by the corrective region towards the portion of the cornea aligned with the annular therapeutic recess of the lens. This is particularly advantageous when the degree of myopia during correction is relatively low, for example, -1.0D. In such embodiments, a relatively small amount of flattening of the central portion of the cornea is required, and thus a small amount of tissue and / or fluid is displaced by the corrective region of the lens. A large radius of curvature (flat profile) of the accommodative region can help direct tissue and / or fluid towards the region of the cornea aligned with the corrective region, so that the annular therapeutic recess can introduce sufficient myopic defocus into the peripheral portion of the cornea. Perhaps, if the accommodative region is relatively flat, it does not act as a reservoir into which the cornea can expand, and therefore movement from the central portion and / or peripheral portion of the cornea towards the region aligned with the accommodative region is inhibited.

[0060] Optionally, the corneal reshaping lens has a corrective region comprising a first section of the posterior surface with a radius of curvature ranging from 7 mm to 9.5 mm, and a second section of the posterior surface constituting an annular treatment recess with a radius of curvature ranging from 5.5 mm to 8.5 mm, provided that the radius of curvature of the posterior surface is smaller than the radius of curvature of the central corrective region. Optionally, the radius of curvature of the accommodative region is in the range of 7.0 mm to 15 mm, and the radius of curvature of the third section is larger than the radius of curvature of the second section constituting the annular treatment recess. Optionally, the radius of curvature of the accommodative region is larger than or equal to the radius of curvature of the corrective region. For example, if the radius of curvature of the first section of the posterior surface constituting the corrective region is in the range of 8.0 mm to 8.5 mm, the radius of curvature of the second section of the posterior surface constituting the annular treatment recess is preferably in the range of 7.7 mm to 8.2 mm, and the radius of curvature of the third section of the posterior surface constituting the accommodative region is preferably in the range of 8.0 mm to 8.5 mm. Such lenses are particularly effective in correcting and treating low myopia, for example, myopia of about -1.0D.

[0061] The accommodative region is preferably positioned within the posterior surface of the lens such that it is tilted toward or away from the center of the corrective region. As understood, the tilt is preferably created in the accommodative region by creating an asymmetric profile within a third segment of the posterior surface of the lens. The accommodative region is preferably asymmetric such that the portion of the accommodative region closest to the annular treatment recess has a smaller radius of curvature than the portion of the accommodative region further away from the annular treatment recess. As understood, such an asymmetric profile tilts the accommodative region toward the annular treatment recess and the corrective region. As a variation, the accommodative region may be asymmetric such that the portion of the accommodative region closest to the annular treatment recess has a larger radius of curvature than the portion of the accommodative region further away from the annular treatment recess. As understood, such an asymmetric profile tilts the accommodative region away from the annular treatment recess and the corrective region. The direction of the tilt of the accommodative region is preferably selected according to the desired flow direction of tissue and / or fluid within the cornea. For example, in a lens designed to treat low myopia (e.g., -1.0D myopia), the treatment area is preferably tilted away from the annular treatment recess and corrective area. This directs corneal fluid and / or tissue towards the portion of the cornea bounded by the annular treatment recess and corrective area, and / or prevents the fluid and / or tissue from moving toward the outer region of the cornea that is preferably bounded by the fitting area. In such a configuration, perhaps more fluid and / or tissue can be used to align with the annular treatment recess and / or corrective area, which can help achieve the desired corneal profile in these areas. In a lens designed to treat high myopia (e.g., -4.0D myopia), the accommodative area is preferably tilted toward the annular treatment recess and corrective area. This allows for directing corneal fluid and / or tissue towards the lateral region of the cornea that is better bounded by the fitting region, and / or away from the portion of the cornea bounded by the annular treatment recess and corrective region.If the adjustment area is tilted toward the annular treatment recess and the corrective area, corneal fluid and / or tissue directed from the central portion of the cornea is likely directed toward the lateral region of the cornea, which can be aligned with the fitting area. Such a configuration also likely prevents the backflow of corneal tissue and / or fluid from the lateral region of the cornea toward the central region. Such a lens configuration allows excess corneal fluid and / or tissue to be directed away from the annular treatment recess, thereby enabling control of desired myopic defocus in the peripheral portion of the lens.

[0062] The lens according to this disclosure may optionally have an accommodative region that directly contacts the annular treatment recess, that is, the outer periphery of the annular treatment recess may define the boundary between the annular treatment recess and the accommodative region. Therefore, the annular treatment recess may be located adjacent to the accommodative region. At the boundary between adjacent accommodative regions and annular treatment recesses, there may be abrupt discontinuous increases or decreases in radial curvature refractive power, depending on the relative radial curvature addition of the annular treatment recess and the accommodative region, respectively.

[0063] Presumably, the radius of curvature of the accommodative region is equal to the radius of curvature of the annular treatment recess. In such embodiments, the accommodative region and the annular treatment recess are preferably spaced apart within the lens so that there is a clear demarcation between the end of one region and the beginning of the other. For example, a portion of the posterior surface of the lens having a radius of curvature equal to the radius of curvature of the corrective region may separate the annular treatment recess from the accommodative region.

[0064] Perhaps one or more additional regions are positioned between the annular treatment recess and the corrective region. Such regions are preferably oriented toward the peripheral portion of the cornea located beneath the annular treatment recess when the lens is worn. For example, such regions may have properties similar to the accommodative region described herein, except that they are located opposite the treatment recess; that is, they align with the inner circumference of the annular treatment recess. Alternatively, such regions may be deflected from the portion of the cornea located beneath the annular treatment recess when the lens is worn. For example, such regions may have properties similar to the annular treatment recess.

[0065] Optionally, the posterior surface of the lens may further have a fitting region for stabilizing the lens against the cornea, the fitting region extending radially outward from the periphery of the accommodative region. Thus, the lens according to this disclosure may have a fitting region for stabilizing the lens.

[0066] The fitting region is a part of the lens located outside the optical zone, and thus the fitting region does not align with the pupil of the eye when the lens is worn, but rather is located outside the peripheral portion of the cornea. When the lens is viewed in plan view, the fitting region surrounds the accommodative region with its center located on the central axis of the lens. Preferably, the fitting region is substantially circular when viewed in plan view. The fitting region has no optical properties but is used to fix the lens to the eye when in use. This helps to prevent the lens from moving or slipping on the eye during use. Optionally, the fitting region has a radius of curvature approximately equal to the radius of curvature of the portion of the eye to be treated. The fitting region may have multiple areas, each with a different radius of curvature. Each area may have a radius of curvature in the range of 8 mm to 12 mm, preferably in the range of 8.5 mm to 10.5 mm, for example, a radius of curvature of about 9 mm is preferable. Presumably, the fitting region is rigid so that it does not flex or change shape under the pressure of fluid being redistributed within the cornea. In this way, the fitting region helps direct fluid / cells into the region of the cornea aligned with the annular region. Optionally, the fitting region may have a larger radius of curvature than the portion of the cornea aligned with the fitting region when the lens is worn. In this way, the fitting region can apply additional pressure to the eye (for example, additional pressure is applied to one side of the cornea by the fitting region). This may be beneficial in redistributing tissue and / or fluid toward the center of the cornea, and the fitting region may be provided in lenses preferably designed to treat relatively low myopia. As a variation, the fitting region may have a smaller radius of curvature than the portion of the cornea aligned with the fitting region when the lens is worn. Such a fitting region has a greater curvature than the portion of the cornea aligned with the fitting region, and therefore, it can be said that the fitting region does not apply additional pressure to the cornea.This allows the eye to expand within an area aligned with the fitting area (i.e., one side of the cornea), which may preferably be provided in a lens designed to treat relatively high myopia. The fitting area may have a width of at least 1 mm, at least 3 mm, or at least 4 mm. The fitting area may have a width of 9 mm or less, 7 mm or less, or 5 mm or less. For example, the fitting area may have a width in the range of 1 mm to 7 mm, for example, 1.5 mm. As can be understood, since the fitting area is annular, the width may be determined as the distance between the circumference of the inner edge of the fitting area and the circumference of the outer edge of the fitting area in the direction of movement from the center of the lens to the edge of the lens (viewed in a plan view of the lens).

[0067] As an option, the lens has an edge lift. The edge lift can help the user lift the lens away from the cornea.

[0068] The method for forming a corneal corrective lens according to this disclosure may include any of the features described above.

[0069] The corneal corrective lens according to this disclosure may optionally reshape the corneal profile to mimic the core properties of a MISIGHT contact lens. Specifically, the lens may provide a corneal profile that includes a central corrective zone (the flattened central portion of the cornea) with a diameter of 3.30–3.40 mm and an add power of +2.0 D, and optionally includes a raised peripheral portion (the peripheral portion of the cornea with increased curvature or myopic defocus) with a diameter of 1.40–1.50 mm.

[0070] Lenses are preferably formed by casting, spin-casting, lathing (turning), or a combination thereof. As those skilled in the art will understand, casting means forming a lens by placing the lens-forming material between a female mold member having a concave lens-forming surface and a male mold member having a convex lens-forming surface.

[0071] The manufacturing method may include the step of forming a female mold member having a concave lens forming surface and a male mold member having a convex lens forming surface. The method may also include the step of filling the gap between the female mold member and the male mold member with bulk lens material. The method may further include the step of curing the bulk lens material to form a lens. As can be understood, the rear and front surfaces of the lens are isomorphic to the concave and convex surfaces and the mold surface, and thus the profile of the lens surface is controlled by the profile of the mold surface.

[0072] An annular therapeutic recess and an accommodative region can be formed in the lens layer by racing, etching, or laser processing the recess or region within the lens layer. It is preferable to first form a lens body having a rear surface, for example, in a mold, without at least one of the annular therapeutic recess and the accommodative region. Perhaps the rear surface of the lens body forms the rear surface of the lens once the annular therapeutic recess and accommodative region are formed. The lens body may have a substantially uniform radius of curvature across the entire rear surface. Perhaps the radius of curvature across the entire rear surface is equal to the radius of curvature of the corrective region. Next, the method includes the step of removing a portion of the lens body using a lathe, or by etching or laser processing, to form a second portion of the rear surface constituting the annular therapeutic recess and / or a third portion of the rear surface constituting the accommodative region. Thus, once the lens body is formed, a portion of the lens body is removed using a lathe, or by etching or laser processing, thereby forming the desired lens having a rear surface according to the present invention. This technique is preferably used to change the curvature of one or more sections of the posterior surface of the lens body, thereby creating an annular therapeutic recess or adjustment region on the posterior surface. The resulting lens body will have the posterior surface according to this disclosure.

[0073] Alternatively or additionally, at least one of the annular therapeutic recess and the accommodative region can be formed in the lens layer by the use of a mold. Optionally, the mold surface can form at least one of a first segment of the posterior surface constituting the corrective region of the lens, a second segment of the posterior surface constituting the annular therapeutic recess of the lens, and a third segment of the posterior surface constituting the accommodative region of the lens. Perhaps the mold forms the corrective region of the lens, and the annular therapeutic recess and accommodative region are formed by another process disclosed herein, such as a lacing method, etching method, or laser processing. The mold may have one or more projections that form at least one of the corrective region, the annular therapeutic recess, or the accommodative region. The shape and curvature of the projections determine the radius of curvature of the segment of the posterior surface of the lens constituting the annular therapeutic recess or the accommodative region.

[0074] At least one of the annular treatment recess and the accommodative region can be formed additionally or alternatively by press-fitting an imprinting arm into the posterior surface of the lens while holding the lens in place. This is preferably done multiple times using imprinting arms of different diameters to form imprints of different dimensions on the posterior surface of the lens. The shape and curvature of the imprinting arm will determine the radius of curvature of the sections of the posterior surface of the lens that constitute the annular treatment recess and the accommodative region.

[0075] As will be recognized by those skilled in the art, the order of steps described with respect to the first aspect of the method, or any other aspect of this disclosure, is not limited to the order provided.

[0076] According to a third aspect of the present invention, a method for manufacturing a corneal corrective contact lens is provided. The contact lens has a posterior surface comprising a number of divisions, each having a radius of curvature, the first division constituting the corrective region of the contact lens, the second division constituting the annular corrective recess of the contact lens, and the third division constituting the accommodative region of the contact lens. This method includes the step of selecting the radius of curvature for each section, and in the step of selecting the radius of curvature, i) Select the radius of curvature of the first section, the radius of curvature of the first section being at least 6 mm, ii) Select the radius of curvature of the second section, and the radius of curvature of the second section is smaller than the radius of curvature of the first section. iii) Select the radius of curvature for the third category, where the radius of curvature for the third category is in the range of 4.5 mm to 15 mm. iv) The step of manufacturing a contact lens such that the posterior surface comprises a number of sections having radii of curvature selected in step i), step ii), and step iii).

[0077] As can be understood, any feature of the first or second aspect of the present invention can be combined with the third aspect of the present invention. For example, the method according to the third aspect can be used to manufacture a lens according to the first aspect. The corrective region, annular treatment recess, and accommodative region of the third aspect of the present invention may include any feature described in relation to the first or second aspect of the present invention. Furthermore, the method according to the third aspect of the present invention may include any feature of the second aspect of the present invention. For example, the lens may be formed in a mold. Optionally, at least one of the annular treatment recess and the accommodative region may be formed by lacing.

[0078] A fourth aspect of the present invention is provided, a method for treating the progression of myopia, comprising the step of providing a lens of the present invention to a patient in need of the lens. As understood, the patient is myopic, and the method comprises the step of treating myopia in one or both eyes of the myopic person. The patient's age is preferably 25 years or younger. The patient's age may be 20 years or younger, or 15 years or younger. The patient's age may be 12 years or younger. The corneal corrective lens of the present disclosure is particularly advantageous for treating myopia in children aged 12 years or younger. Perhaps, in children aged 12 years or younger, myopia has not yet developed or is only mild, and therefore it is easier to slow or prevent its progression or exacerbation. Perhaps, the use of the corneal corrective lens of the present disclosure is particularly effective in preventing the development of myopia, or at least slowing its progression, in patients with a family history of myopia (i.e., genetic predisposition).

[0079] A method for treating the progression of myopia may include the step of reshaping the patient's cornea by fitting the lens of the present invention to the patient's cornea. This method can correct myopia so that the patient has clear long-distance distance vision when the lens is removed from the eye. This method can introduce myopia defocus into the peripheral portion of the cornea, as described herein. For example, this method can introduce myopia defocus of at least +1D, at least +1.5D, at least +2D, at least +4D, at least +6D, or at least +8D into the cornea. The radius of curvature of the corrected area of ​​the cornea and the myopia defocus area of ​​the cornea are determined by the corrected area and the treatment recess of the lens, respectively. For example, the corrected area of ​​a lens with a diameter of approximately 3 mm can correct the central portion of the cornea with a diameter of approximately 3 mm.

[0080] Once fitted to the patient's eye, the lens should be worn for a sufficient amount of time for the corneal shape to conform to, or at least substantially conform to, the shape of the lens. For example, the lens should be worn for at least 5 hours, or at least 8 hours. Preferably, the lens is worn overnight while the patient is sleeping, allowing the cornea of ​​the eye to reshape while the patient is not concerned with their vision. Once the cornea has reshaped and has a profile substantially identical to the posterior surface of the lens, the lens should be removed. The reshaped corneal profile will last for several hours, for example, at least 5 hours, at least 8 hours, or at least 12 hours. Thus, the patient's distance vision improves compared to the eye's natural state (i.e., the patient's vision before treatment with the lens). Once the lens is removed from the eye, the compressive force is no longer exerted on the cornea, and therefore the cornea returns to its natural state. The cornea can be reshaped again by reinserting the lens. Thus, the patient can wear the lenses every day, but can also remove them during the day.

[0081] The present invention aims to control the location and refractive power characteristics of myopic defocus introduced into the peripheral portion of the cornea by forcibly flattening the central portion of myopia. Additionally or alternatively, the present invention aims to control the dimensions and curvature of the corrected central portion of the cornea. This can be achieved by using annular treatment recesses and accommodative regions in the corneal corrective lenses described herein.

[0082] The corneal corrective contact lens 201 (Figure 2A) of the present invention may be suitable for correcting and treating relatively high myopia (for example, myopia of -4D). The lens 201 is configured to be worn on the cornea of ​​an eye (not shown). The lens 201 has a posterior surface 202 and an anterior surface 204. A first division of the posterior surface 202 constitutes a central corrective region 206. The first division of the posterior surface 202 that constitutes the central corrective region 206 is greater than the radius of curvature of the cornea. LargeThe lens has a radius of curvature. A second division of the posterior surface 202 constitutes an annular treatment recess 208. The annular treatment recess 208 is formed by a second division of the posterior surface having a radius of curvature smaller than that of the corrective area 206. A third division of the posterior surface 202 constitutes an accommodative area 210. The accommodative area 210 is formed by a third division of the posterior surface of the lens having a radius of curvature smaller than both that of the corrective area 206 and the annular treatment recess 208. A fitting area 212 is located around the periphery of the lens. The fitting area 212 helps to stabilize the lens 201 against the eye when in use. The fitting area 212 may have a continuous radius of curvature over its entire width, or it may have multiple radii of curvature over its entire width.

[0083] Lens 208 has four concentric regions (Figure 2B). The center of each region is located on the axis of lens 201. The central portion of lens 201 is the corrective region 206. The annular treatment recess 208 extends radially outward from the periphery of the corresponding region 206. Adjacent to the annular treatment recess 208 is the accommodative region 210. The outermost region of lens 208 is the fitting region 212.

[0084] The corneal corrective contact lens 301 (Figure 3A) may be suitable for correcting and treating relatively low myopia (for example, -1D myopia). The lens 301 is configured to be worn on the cornea of ​​the eye (not shown). The lens 301 has a posterior surface 302 and an anterior surface 304. A first segment of the posterior surface 302 constitutes a central corrective area 306. The first segment of the posterior surface 302 constituting the central corrective area 306 is greater than the radius of curvature of the cornea (not shown) to be treated. LargeThe lens has a radius of curvature. Since the lens is provided to treat relatively low myopia, the corrective area 306 is preferably more curvature or flatter than the corrective area 206 shown in Figure 2A. A second division of the posterior surface 302 constitutes an annular treatment recess 308. The annular treatment recess 308 is composed of a second division of the posterior surface having a radius of curvature smaller than that of the corrective area 306. A third division of the posterior surface 302 constitutes an accommodative area 310. The accommodative area 310 is composed of a third division of the posterior surface of the lens having a radius of curvature equal to that of the corrective area 306 and larger than that of the annular treatment recess 308. Thus, in contrast to the lens 201 shown in Figure 2A, the lens 301 shown in Figure 3A has a relatively flat accommodative area. A fitting area 312 is located at the periphery of the lens. The fitting area 312 helps to stabilize the lens 301 against the eye when in use. The fitting region 312 may have a continuous radius of curvature over its entire width, or it may have multiple radii of curvature over its entire width.

[0085] Lens 308 has four concentric regions (Figure 3B). The center of each region is located on the axis of lens 301. The central portion of lens 301 is the corrective region 306. The annular treatment recess 308 extends radially outward from the periphery of the corrective region 306. Adjacent to the annular treatment recess 308 is the accommodative region 310. The outermost region of lens 301 is the fitting region 312.

[0086] For use, the corneal corrective contact lens 401 is placed on the surface of the cornea 414 to be treated (Figure 4A) (only the uppermost surface of the cornea 414 is shown, and as can be understood, the uppermost surface of the cornea includes the epithelial layer 416). The corrective area 406 is aligned with the central portion of the cornea 414, which includes the apex of the surface of the cornea 414. The annular corrective recess 408 is aligned with the peripheral portion of the surface of the cornea 414. For clarity, the accommodative area is not shown in Figure 4A, but is located between the annular corrective recess 408 and the fitting area 412. Figure 4A is shaded differently to show different regions of the lens.

[0087] 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. Due to the structure and physiological characteristics of the corneal epithelium, its thickness can be changed by applying sustained pressure. The fluid and / or tissue (and other organic matter normally found in the eye) of the corneal epithelial layer 416 can be redistributed from one area of ​​the cornea 414 to another by applying pressure to the surface of the cornea 414. The radius of curvature of the corrective area 406 of the lens 401 is greater than the radius of curvature of the cornea 414 to be treated. Large Therefore, the corrective area 406 contacts at least the central portion of the cornea 414 and applies pressure or compressive force to the apex of the cornea 414 (indicated by the central vertical arrow in Figure 4A). As a result, the fluid and / or tissue of the corneal epithelium 416 is pushed to the peripheral portion of the cornea 414, as shown by the arrows radiating from the center of the cornea 414 in Figure 4A. The annular corrective recess 408 aligns with the peripheral portion of the cornea 414 and provides space for expansion of the cornea 414 as a result of the redistribution of cells / fluids from the central to the peripheral region of the cornea 414.

[0088] The surface profile of the cornea 414 before treatment (dashed line) differs from the surface profile of the cornea 414 after treatment (thick line) (Figure 4B). Thus, by utilizing the redistribution of fluids and / or cells within the epithelial layer 416 of the cornea 414, the corneal curvature and thus the optical refractive power can be increased or decreased. The central portion of the cornea 414 aligned with the corrective area 406 is flattened or has less curvature in the treated cornea 414 compared to the cornea 414 before treatment. Because the curvature of the central portion of the treated cornea 414 is small, the focal point of light reflected from distant objects is centered on the retina rather than in front of it, thus correcting visual acuity. In contrast, the peripheral portion of the cornea 414 that was located adjacent to the annular treatment recess 408 is a raised portion or a highly curvilinear portion of the treated cornea 414 compared to the pre-treatment portion. After treatment, the curvature of the peripheral portion of cornea 414 is greater than that of the central portion, resulting in a positive refractive power exceeding the base power of the central portion. The area of ​​add power or myopia defocus in the peripheral portion of the lens is thought to slow or limit the progression of myopia.

[0089] The corrected corneal shape 414 is maintained even after the lens 401 is removed from the eye. Over time, the shape of the cornea 414 will relax towards its uncorrected or pre-treatment state. When the shape of the cornea 414 reverts to its uncorrected state to the extent that long-distance distance vision is impaired, it is advisable to reposition the lens 401 onto the cornea 414 to reshape its profile.

[0090] According to the present invention, the dimensions, including the diameter, width, curvature, and shape of the corrective region, annular treatment recess, and accommodative region of the lens, can be adjusted to influence the surface profile brought into the cornea being treated. For example, the diameter of the corrective region of the lens affects the diameter of the central portion of the cornea that is flattened. It is desirable to provide a standard diameter of the central portion of the cornea that is flattened for any myopic eye treated with the lens of the present invention. This can be achieved by selecting the diameter of the central region of the lens that corrects the diameter of the central portion of the cornea, which is the same for all myopic eyes being treated. For example, the central portion of the cornea corrected by the corrective region of the lens may have a diameter of approximately 3 mm. Perhaps the diameter of the corrective region is selected according to the degree of myopia to be treated. For example, a lens for treating low myopia may have a corrective region with a smaller diameter than a corrective region for treating high myopia. However, the radius of curvature of the lens corrective region varies from lens to lens depending on the myopic eye being treated, because high myopia requires further flattening. Generally, the greater the amount of myopic refractive error to be corrected, the flatter the central region becomes (i.e., the larger the radius of curvature of the corrective region). The annular treatment recess of the lens always has a larger radius of curvature than the central corrective zone of the lens for providing the add power to the cornea. The radius of curvature, width, and shape of the annular treatment recess can be adjusted for each lens according to the radius of curvature of the corrective region. Similarly, the function of the accommodative region of the lens also depends on the dimensions of the corrective region, and thus the dimensions of this region will change with the curvature of the corrective region or the degree of myopia being corrected. As described herein, the accommodative region may be a recess for accumulating corneal volume during treatment, or, as a variation, a relatively flattened and inclined region to reduce or facilitate volume accumulation in the peripheral portion of the cornea aligned with the annular treatment recess of the lens. Presumably, the greater the difference in refractive power between the orthodontic area and the ring-shaped treatment recess, the more the accommodative area becomes flatter (i.e., the radius of curvature of the accommodative area becomes larger).For example, the difference in refractive power between the corrective region and the annular therapeutic recess is preferably +1D, +1.5D, +2D, +2.5D, +3D, +3.5D, +4D, +4.5D, +5D, +5.5D, +6D, +6.5D, or +7D. As can be understood, the difference in refractive power refers to the difference in refractive power brought about by the central portion of the cornea aligned with the corrective region and the peripheral portion of the cornea aligned with the annular therapeutic recess. The accommodative region has a radius of curvature such that sufficient epithelial fluid and / or tissue is distributed to the peripheral portion of the cornea to cause the desired myopia defocus. If the difference in refractive power between the corrective region and the annular therapeutic recess of the lens is large, then perhaps an insufficient amount of epithelial tissue and / or fluid is pushed aside by the corrective region, and thus an insufficient amount of tissue and / or fluid is directed toward the peripheral portion of the cornea to cause the desired myopia defocus. Additionally or alternatively, it is necessary that substantially all of the displaced fluid and / or tissue be directed towards the peripheral portion of the cornea aligned with the treatment recess, thus avoiding the movement of displaced tissue and / or fluid toward the periphery of the cornea. Therefore, when the refractive power difference between the corrective area of ​​the lens and the annular treatment recess is large, a relatively flat accommodative area may be desirable for directing tissue and / or fluid toward the peripheral portion aligned with the annular treatment recess. In contrast, when the refractive power difference between the corrective area and the annular treatment recess is small, it is desirable that sufficient fluid and / or tissue be directed towards the peripheral portion of the cornea aligned with the annular treatment recess. In this case, it can be said that the accommodative area should be a recess that accommodates the excess displaced fluid and / or tissue. Therefore, when the refractive power difference between the corrective area of ​​the lens and the annular treatment recess is small, a relatively curvatured accommodative area (i.e., a recess) may be desirable for directing tissue and / or fluid toward the peripheral portion of the cornea aligned with the annular treatment recess. To ensure understanding, when we speak of "adjusting" or "changing" the dimensions of a lens area, this does not refer to a change in the lens's dimensions once it has been formed. Rather, it means that a lens can be designed by selecting from a range of dimensions and then manufacturing a lens of the selected dimensions. The various adjustable dimensions will now be explained with reference to Figures 5 to 8.The arrows in the figure indicate the movement of fluid and / or tissue within the cornea according to the profiles of the corrective region, annular therapeutic recess, and accommodative region. The following embodiments relate to lenses suitable for producing a +2D myopia defocus in the peripheral portion of the cornea. As understood, the lenses of the present invention are preferably designed to produce a myopia defocus of less than +2D or greater than +2D in the peripheral portion of the lens. The dimensions of the corrective region, annular therapeutic recess, and accommodative region will be selected according to the desired myopia defocus to be produced in the peripheral portion of the lens, as described herein.

[0091] By modifying or altering certain regions and profiles of lens 401, a specific optical profile can be produced in the cornea (Figure 5). Referring to Figure 5, the left and right sides of lens 401 show different profiles of lens regions, but it should be understood that this merely illustrates the various dimensions of the regions that can be modified. As can be understood, the lens of the present invention may have regions that are uniform in dimension with respect to any meristean of the lens. The central corrective region 406 of lens 401 can be made smaller or larger in diameter depending on the desired diameter of the central portion of the cornea 414 to be flattened. The curvature of the corrective region 406 can also be altered depending on the amount of myopia to be corrected. For example, a flattened or less curvatured central corrective region 406 may be effective in treating high myopia (e.g., -4.0D myopia), while a more curvatured central corrective region 406 may be effective for low myopia (e.g., -1.0D myopia). The shape of the central corrective region 406 can also be altered. For example, the central corrective region 406 may be symmetrical or asymmetrical. The shape of the corrective region 406 is preferably aspherical. An aspherical profile is particularly advantageous in providing a more uniform profile across the entire central portion of the corrected cornea. Similarly, the shape, diameter, and width of the annular corrective recess 408 and the accommodative region (not shown in Figure 5) can also be modified. In addition, the dimensions of the fitting region 412 can be modified to control the fluid and / or tissue redistribution state of the corneal epithelial layer 416. For example, the curvature of the fitting region 416 can be steep or flat. As can be seen, in Figure 5, the left side of the lens 401 has a steep fitting region 412, which is steeper than the corneal surface profile 414. The steep fitting region 412 presses against one side of the cornea 414 to move the fluid towards the center of the cornea 414. The right side of lens 401 shows a fitting region 412 that is less steep than the cornea 414. The less steep fitting region 412 can extend one side of the cornea 414, and thus the fluids and tissues of the corneal epithelium 416 are redistributed away from the center of the cornea 414 and toward one side of the cornea 414.Presumably, the fitting region 412 has numerous areas, each with a different radius of curvature. Thus, the pressure applied according to this region of the lens can be controlled more precisely.

[0092] The dimensions of the annular recess of the lens can be modified. Referring to Figure 6, the left side of lens 401 shows a change in the width of the annular treatment recess 408 (only the right side is labeled). The right side of lens 401 shows a change in the inclination or asphericity of the annular treatment recess 408. The annular treatment recess 408 can be tilted toward the central correction area 406, or tilted toward the central correction area 406. By using the inclination of the annular treatment recess 408, the direction of tissue and / or fluid flow in the epithelial layer 416 of the cornea 414 can be controlled. For example, if the annular treatment recess 408 is tilted toward the central correction area 406, the tissue and / or fluid of the epithelial layer 416 can be prevented from moving toward the periphery of the cornea 414. This is advantageous when treating low myopia. In contrast, if the annular treatment recess 408 is inclined toward the central orthodontic area 406, the movement of tissue and / or fluid of the epithelial layer 416 toward the periphery of the cornea 416 can be facilitated. This is advantageous when treating high myopia.

[0093] Furthermore, the dimensions of the annular treatment recess can also be adjusted (Figure 7). For clarity, the accommodative region of lens 401 is not shown. On the left side of lens 401, the change in curvature of the annular treatment recess 408 (only the right side is labeled) is shown. The curvature of the annular treatment recess 408 affects the myopic defocus brought about in the cornea 414. The smaller the radius of curvature of the annular treatment recess 408 (the larger the curvature of the annular treatment recess 408), the greater the curvature of the cornea 414 resulting from the redistribution of fluid and / or tissue in the epithelial layer 416 that can be accepted by the annular treatment 408. On the right side of lens 401, the change in the position of the annular treatment recess 408 is shown. The position of the annular treatment recess 408 determines the position of the myopic defocus brought about in the cornea 414.

[0094] The dimensions of the accommodative region 410 can also be adjusted. Referring to Figure 8, the left side of the lens 401 shows the changes in curvature and width of the accommodative region 410 (only the right side is labeled). The curvature of the accommodative region 410 affects the curvature of the cornea 414 in the region aligned with the accommodative region 410. The right side of the lens 401 shows the changes in asphericity and inclination of the accommodative region 410. The arrows indicate the movement of fluid and / or tissue within the epithelial layer 416 of the cornea 414. If the accommodative region 410 is concave, the movement of fluid and / or tissue within the cornea 414 is directed toward the accommodative region 410. If the accommodative region 410 is flat, the movement of fluid and / or tissue within the cornea 414 is directed toward the annular therapeutic recess 408 (dashed arrow in Figure 8). The inclination of the accommodative region 410 can also affect the direction of movement of fluid and / or tissue within the epithelial layer 416 of the cornea 414.

[0095] A method 500 for manufacturing a lens of the present invention (Figure 9) includes a first step 501 of forming a lens having a posterior surface. This step may include a step of forming a lens body having a posterior surface. Next, the posterior surface of the lens body is modified in the following steps to form the posterior surface of the lens of the present invention. The method includes a step 502 of forming a corrective region consisting of a first segment of the posterior surface. The method includes a step 503 of forming an annular treatment recess consisting of a second segment of the posterior surface. The method includes a step 504 of forming an adjustment region consisting of a third segment of the posterior surface. Perhaps the steps of forming the corrective region 502, forming the annular treatment recess 503, and forming the adjustment region 504 are performed simultaneously while the lens or lens body is formed in step 501. For example, the lens is often formed by placing it in a mold, which is shaped to form a posterior surface of the lens having multiple curvatures, the first section of the posterior surface having a curvature that defines the corrective region, the second section of the posterior surface having a curvature that defines the annular treatment recess, and the third section of this surface having a curvature that defines the accommodative region. In a modified example, the steps of forming the corrective region 502, forming the annular treatment recess 503, and forming the accommodative region 504 may be performed sequentially (and in any order). For example, the method may include a step 501 of forming the lens or lens body in the absence of at least one of the annular treatment recess or the accommodative region. In this situation, the posterior surface of the lens or lens body may have a radius of curvature equal to the radius of curvature of the corrective region over substantially the entire surface of the constituent region. Next, the step of forming the annular treatment recess 503 or the step of forming the adjustment region 504 is often carried out by racing to modify one or more sections on the rear surface of the lens or lens body, so that these sections have a radius of curvature that defines at least one of the annular treatment recess and the adjustment region according to the present invention.

[0096] A method 600 for manufacturing a lens of the present invention (Figure 10) is shown, the lens having a posterior surface comprising a number of divisions, each having a radius of curvature. A first division of the posterior surface of the lens constitutes the corrective region of the lens, a second division constitutes the annular corrective recess of the lens, and a third division constitutes the accommodative region of the lens. The method includes a step 601 of selecting the radius of curvature of the first division of the posterior surface of the lens. The radius of curvature of the first division is at least 6 mm. The method includes a step 603 of selecting the radius of curvature of the second division of the posterior surface of the lens. The radius of curvature of the second division is smaller than the radius of curvature of the first division. The method includes a step 605 of selecting the radius of curvature of the third division of the posterior surface of the lens. The radius of curvature of the third division is in the range of 4.5 mm to 15 mm. The method 600 finally includes step 607 of manufacturing a lens such that the rear surface has a number of sections with radii of curvature selected in steps 601, 603, and 605.

[0097] While the present invention has been described and illustrated with reference to specific embodiments, as will be apparent to those skilled in the art, this disclosure leads to a number of variations not specifically shown herein.

[0098] Examples Now, an exemplary corneal corrective lens of the present invention will be described. The following embodiments relate to a lens suitable for producing a +2D myopia defocus in the peripheral portion of the cornea. As will be understood, the lens of the present invention is preferably designed to produce a myopia defocus of less than +2D or greater than +2D in the peripheral region of the lens. The dimensions of the corrective region, the annular corrective recess and the accommodative region are selected based on the desired myopia defocus to be produced in the peripheral region of the lens, as described herein.

[0099] Example 1 - Correction and treatment of low myopia In the first embodiment, a corneal corrective lens suitable for correcting a low myopia of -1.00D was designed.

[0100] Assuming a nominal corneal refractive power of 42D (8.03mm) and a refractive index of -1.00DS, the following parameters were calculated for each region of the lens in Example 1.

[0101] Region 1 (Corrected Region): The required base optical zone radius (BOZR) for the central corrected region = 42D (nominal corneal refractive power) + (sum) - 1.00 (myopia correction) + (sum) - 0.75 (Jessen coefficient) = 40.25D. This correlates with a radius of curvature of 8.39 mm. The diameter of the central zone is selected to be 3.36 mm.

[0102] Region 2 (annular treatment recess): To achieve an add degree of +2.00D, Region 2 must have a curvature of 40.25D + 2D = 42.25D. This correlates with a radius of curvature of 7.99mm. The width of Region 2 was selected to be 1.4mm.

[0103] Region 3 (Adjustment Region): The radius of curvature of Region 3 was selected to 8.39 mm. The width of Region 3 was selected to 1 mm.

[0104] Region 4 (Fitting Region): 0.0 to 0.9 mm flatter than the BOZR in Region 1, i.e., 9.29 mm. The width is 1.5 mm.

[0105] Region 5 (Fitting Region): 0.0 to 0.9 mm flatter than the BOZR in Region 1, i.e., 9.29 mm. The width is 1.5 mm.

[0106] The diameter and curvature of regions 4 and 5 (fitting regions) can be varied according to the eccentricity value of the cornea. These zones are used to stabilize the lens on the cornea.

[0107] Area 6 (edge ​​lift) has a radius of 0.1 mm. The edge lift is the outermost part of the lens that does not come into contact with the cornea when the lens is worn.

[0108] Regarding the correction of low myopia, the amount of fluid and / or cellular tissue that needs to be displaced from the central corrective region of the cornea is small compared to high myopia, because the cornea requires a small degree of flattening. In the lens of Example 1, region 3 (accommodative region) has a larger radius of curvature than region 2 (annular corrective recess). Although not bound by theory, it is thought that region 3 can direct the displaced fluid and / or cells into the corneal region bounded by region 2. This can result in a large positive curvature and a large add in the corneal region bounded by region 2. The refractive power in the corneal region bounded by region 2 is intended to have an add at least +2D greater than that in the corneal region bounded by the corrective region (region 1).

[0109] Example 2 - High Myopia In the second embodiment, a corneal corrective lens suitable for correcting a high degree of myopia of -4.00D was designed.

[0110] Assuming a nominal corneal refractive power of 42D (8.03mm) and a refractive index of -4.00DS, the following parameters were calculated for each region of the lens in Example 2.

[0111] Region 1 (Corrective Region): The required base optical zone radius (BOZR) for the central corrective region = 42D (nominal corneal refractive power) + (sum) - 4.00 (myopia correction) + (sum) - 0.75 (Jessen coefficient) = 37.25D. This correlates with a radius of curvature of 9.06 mm (i.e., larger than the radius of curvature of Region 1 required for the low myopia in Example 1). The diameter of the central corrective zone is selected to be 3.36 mm.

[0112] Region 2 (annular treatment recess): To achieve an add degree of +2.00D, Region 2 must have a curvature of 37.25D + 2D = 39.25D. This correlates with a radius of curvature of 8.6mm. The width of Region 2 was selected to be 1.4mm.

[0113] Region 3 (Adjustment Region): The radius of curvature of Region 3 was selected to 8.18 mm. The width of Region 3 was selected to 1 mm.

[0114] Region 4 (Fitting Region): 0.0 to 0.9 mm flatter than the BOZR in Region 1, i.e., 9.96 mm. The width is 1.5 mm.

[0115] Region 5 (Fitting Region): 0.0 to 0.9 mm flatter than the BOZR in Region 1, i.e., 9.96 mm. The width is 1.5 mm.

[0116] The diameter and curvature of regions 4 and 5 (fitting regions) can be varied according to the eccentricity value of the cornea. These zones are used to stabilize the lens on the cornea.

[0117] Area 6 (edge ​​lift) has a radius of 0.1 mm. The edge lift is the outermost part of the lens that does not come into contact with the cornea when the lens is worn.

[0118] Regarding the correction of high myopia, greater central flattening of the cornea must occur than in the case of low myopia. As a result, a large amount of cells and / or cellular tissue are pushed out from the central corrective area. Typically, the displacement of cells and / or fluids into the peripheral part of the cornea results in a myopia correction zone greater than +2D, because a large amount of tissue and / or fluid needs to be accommodated in the reverse curve. However, in order to control the diameter of the myopia correction zone and limit the refractive power shift to stay within the desired range of +2D, area 3 (accommodative area) has a steeper curvature than area 2 (annular corrective recess). Although not bound by theory, area 3 can be thought to act as a well or reservoir for excess tissue and / or fluid that is displaced by the corrective zone (area 1) and cannot be accommodated by the annular corrective recess (area 2).

[0119] In this embodiment, the curvature of the annular treatment recess and accommodative region was modified to achieve the desired add degree to the peripheral cornea. However, it is possible that the amount of fluid and / or tissue accepted by the peripheral cornea can be controlled by additionally or alternatively modifying the diameter of the annular treatment recess and accommodative region.

[0120] In the above description, integers or elements having known, obvious, or predictable equivalents are referred to herein as if they were described individually. Refer to the claims that define the true scope of the invention, which should be considered to include any such equivalent. Furthermore, as the reader will understand, integers or features described in this disclosure as advantageous, favorable, etc., are optional and do not limit the scope of the independent claims. Moreover, it should be understood that while some embodiments of the invention may be beneficial, such optional integers or features may not be desirable and therefore may not be described in other embodiments.

Claims

1. A corneal corrective contact lens that corrects myopia by reshaping a portion of the cornea in myopic individuals, and also slows its progression. The corneal reshaping contact lens has a posterior surface that contacts the portion of the cornea to be reshaped, and the posterior surface is The cornea has a corrective region that reduces the curvature of the posterior surface, and the corrective region is composed of a first division of the posterior surface having a radius of curvature. The cornea has an annular treatment recess that causes myopia defocus in the peripheral portion, the annular treatment recess is formed by a second portion of the posterior surface that extends radially outward from the periphery of the corrective area and has a radius of curvature smaller than that of the first portion, and the radius of curvature of the second portion is configured such that the annular treatment recess causes myopia defocus of at least +1D and less than +12D in the peripheral portion of the cornea. The device has an accommodative region that adjusts the myopia defocus caused by the annular treatment recess, and the accommodative region is formed by a third division of the rear surface that extends radially outward from the periphery of the annular treatment recess and has a radius of curvature. The corneal correcting contact lens is configured according to the following cases: (i) correcting high myopia or (ii) correcting low myopia, that is, (i) The radius of curvature of the first section of the posterior surface of the corneal contact lens constituting the corrective region is in the range of 8.8 mm to 9.3 mm. The radius of curvature of the second section of the posterior surface of the corneal reshaping contact lens constituting the annular treatment recess is in the range of 8.3 mm to 8.8 mm, provided that the radius of curvature of the second section is smaller than the radius of curvature of the first section of the posterior surface. The radius of curvature of the third section of the posterior surface of the corneal corrective contact lens constituting the adjustment region is in the range of 7.9 mm to 8.4 mm, provided that the radius of curvature of the third section is smaller than the radius of curvature of the first section of the posterior surface. 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. (ii) The radius of curvature of the first section of the posterior surface of the corneal corrective contact lens constituting the corrective area is in the range of 7 mm to 9.5 mm. The radius of curvature of the second section of the posterior surface of the corneal reshaping contact lens constituting the annular treatment recess is in the range of 5.5 mm to 8.5 mm, provided that the radius of curvature of the second section is smaller than the radius of curvature of the first section of the posterior surface. The radius of curvature of the third section on the posterior surface of the corneal corrective contact lens constituting the adjustment region is in the range of 7.0 mm to 15.0 mm, and the radius of curvature of the third section is greater than the radius of curvature of the second section constituting the annular treatment recess. The radius of curvature of the adjustment region is greater than the radius of curvature of the correction region. The corneal corrective contact lens is configured according to (ii) above, and the radius of curvature of the first section of the posterior surface of the corneal corrective contact lens constituting the corrective area is in the range of 8.0 mm to 8.5 mm. The radius of curvature of the second section of the posterior surface of the corneal reshaping contact lens constituting the annular treatment recess is in the range of 7.7 mm to 8.2 mm, provided that the radius of curvature of the second section is smaller than the radius of curvature of the first section. The radius of curvature of the third section on the posterior surface of the corneal corrective contact lens constituting the adjustment region is in the range of 8.0 mm to 8.5 mm, and the radius of curvature of the third section is greater than the radius of curvature of the second section constituting the annular treatment recess. A corneal corrective contact lens in which the radius of curvature of the adjustment region is greater than the radius of curvature of the correction region.

2. The corneal corrective contact lens according to claim 1, wherein the corrective area has a diameter in the range of 1 mm to 8 mm.

3. The corneal corrective contact lens according to claim 1, wherein at least one of the annular treatment recess and the adjustment region has a width in the range of 0.5 mm to 5.5 mm.

4. The contact lens according to claim 1, wherein the corrective region is formed by a first division of the posterior surface of the aspherical corneal corrective contact lens.

5. The contact lens according to claim 1, wherein at least one of the second portion of the posterior surface of the corneal reshaping contact lens constituting the annular treatment recess or the third portion of the posterior surface of the corneal reshaping contact lens constituting the adjustment region has an asymmetrical profile.

6. The contact lens according to claim 1, wherein the posterior surface of the corneal correcting contact lens further has a fitting region for stabilizing the corneal correcting contact lens with respect to the cornea, and the fitting region extends radially outward from the periphery of the accommodative region.

7. A method for manufacturing a corneal reshaping contact lens according to claim 1, wherein the corneal reshaping contact lens is for correcting and treating myopia by reshaping a portion of the myopic cornea, and the method includes the step of forming the posterior surface of the corneal reshaping contact lens, in which the step of forming the posterior surface The first portion of the posterior surface is formed, the first portion constitutes the corrective area of ​​the corneal corrective contact lens, and also has the radius of curvature described in claim 1, The second portion of the posterior surface extends radially outward from the periphery of the corrective region, the second portion constitutes the annular treatment recess, and also has a radius of curvature smaller than the radius of curvature of the first portion, the radius of curvature of the second portion being as described in claim 1, and the annular treatment recess causes myopia defocus of at least +1D and less than +12D in the peripheral portion of the cornea. A method comprising forming the third portion of the rear surface extending radially outward from the periphery of the annular treatment recess, wherein the third portion constitutes the adjustment region and also has the radius of curvature described in claim 1.

8. The method according to claim 7, comprising the steps of first forming the corneal reshaping contact lens without at least one of the annular treatment recess or the adjustment region, and second forming the second portion of the posterior surface constituting the annular treatment recess or the third portion of the posterior surface constituting the adjustment region by changing the curvature of the portion of the posterior surface of the corneal reshaping contact lens using a lathe.

9. The method according to claim 7, comprising the step of forming the corneal corrective contact lens in a mold, wherein one surface of the mold constitutes at least one of the following: a first portion of the posterior surface constituting the corrective region of the corneal corrective contact lens; a second portion of the posterior surface constituting the annular treatment recess of the corneal corrective contact lens; and a third portion of the posterior surface constituting the adjustment region of the corneal corrective contact lens.

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