Ophthalmic lens including a peripheral zone with additional power offset and spatially modulated optical parameters

Abstract

An ophthalmic lens includes a central zone having at least a first power and a peripheral zone having an optical parameter that is spatially modulated with an additional power offset relative to the at least first power. In some embodiments, the central zone has a diameter in the range of 2.0 to 5.0 millimeters. In some embodiments, the central zone is no more than 1 millimeter smaller than the wearer's pupil. The spatially modulated optical parameter can include optical power, optical scattering, or optical transmission.

Description

Technical Field

[0001] Methods and apparatus for reducing or eliminating myopia progression, including ophthalmic lenses, and more specifically, methods and apparatus for reducing or eliminating myopia progression, including ophthalmic lenses with peripheral regions having optical parameters of additional focal power shift and spatial modulation. Background Technology

[0002] Myopia is an eye condition that causes distant objects (e.g., more than six meters away) to focus in front of the retina, resulting in blurred vision. Myopia is usually corrected by using ophthalmic lenses with sufficient negative power to focus distant objects on the central retina, while adjusting the eye's lens to focus near objects on the central area of ​​the retina.

[0003] Most commonly, myopia occurs when the eye overgrows, causing an imbalance between the eye's axial length and its focal power. Myopia is usually a progressive disease associated with the gradual elongation of the eye. Due to the elongation of the eye caused by progressive myopia, many undesirable pathologies can occur (e.g., retinal detachment and glaucoma).

[0004] It is now generally believed that the increase in the axial length of the eye in growing animals is controlled by a feedback mechanism that occurs within the eye, allowing light entering the eye to focus on the central area of ​​the retina. In emmetropia, this mechanism works well and the axial length and focal power of the eye remain in balance, allowing light to focus on the central area of ​​the retina as the eye grows; however, in myopia, excessive elongation occurs, while in hyperopia, insufficient elongation results in poorly focused light being projected onto the central area of ​​the retina.

[0005] Several theories exist regarding the eye's feedback mechanism. One theory suggests that the position of the peripheral image controls eye growth. More specifically, this theory posits that when the peripheral focal plane is located behind the retina (i.e., posterior), it generates a stimulus that increases eye length. According to this theory, multi-zone ophthalmic lenses used to control myopia progression are designed with a peripheral zone that has a refractive power offset relative to the central region of the lens, thereby shifting the focal plane to move in front of the peripheral retina (i.e., anterior) and eliminating the stimulus to growth.

[0006] In lenses manufactured according to this theory, the lens is constructed such that visual rays (i.e., rays that form a perceptible visual image) pass essentially only through the central region of this multi-region lens, and the peripheral regions are located radially outside the central region to guide light beyond the central visual portion of the retina. Therefore, if the central region is configured for single vision, under normal accommodation of the eye, only the image formed by the central region will focus on the retina, and the light passing through the peripheral regions will focus in front of the retina. At any given time, the image formed by the central region can be a distant or near object, depending on the eye's accommodation state.

[0007] Multi-zone lenses with peripheral regions having an additional focal power offset relative to the central region are understood to differ from multi-zone bifocal contact lenses, in which the central and outer regions of the lens cover the pupil such that visual rays are intercepted by both the central and outer regions. In bifocal lenses, because the outer and central regions have different focal powers, visual rays from these regions always form two images on the central retina (one focused image and one out-of-focus image). At any given time, depending on the eye's accommodation state, the focused image can be a distant object or a near object.

[0008] Although lenses with a peripheral region having an additional focal power offset relative to the central region of the lens have been shown to be effective in suppressing myopia progression in some wearers, others have not achieved the desired suppression and / or their vision has been impaired by interference (such as glare and halo) caused by stray light passing through the peripheral region of the lens. Summary of the Invention

[0009] It is believed that the lack of utility for some wearers of conventional lenses designed to suppress myopia progression by using additional focal power shift in the peripheral region is due to (1) the specified lens allows peripheral hyperopic astigmatism to occur in some accommodative states of a given wearer’s eye and / or (2) some wearers’ eyes have a low response to peripheral astigmatism.

[0010] Various aspects of the present invention relate to a multi-zone ophthalmic lens comprising a peripheral region having an additional power offset relative to a central region, and the peripheral region also having spatial modulation optical parameters. When a given wearer's eye is exposed to peripheral hyperopic astigmatism in a given accommodative state, the spatial modulation optical parameters provide suppression of myopia progression. Furthermore, for wearers with a lower response to peripheral astigmatism, the modulation optical parameters provide additional operating modes to suppress myopia progression.

[0011] Multi-zone lenses according to some aspects of the invention (i.e., lenses comprising peripheral regions with additional power offset relative to the central region, having spatially modulated optical parameters) provide a given utility for reducing or eliminating myopia progression, which is less likely to cause perceptible visual impairments (e.g., glare and halos) compared to multi-zone lenses that provide the same utility but comprise peripheral regions with uniform (i.e., unmodulated) power offset. For example, as a result of the effect caused by modulation of the optical parameters, the additional power offset between the central and peripheral regions can be reduced, thereby leading to a reduction in glare and halos.

[0012] Since progressive myopia most commonly affects children and young adults, the diameter of the central optical zone of a lens according to various aspects of the invention can be greater than about 3 mm to reasonably ensure that the central area is larger than the wearer's pupil under illumination. However, as understood in the art, due to the so-called Stiles-Crawford effect, light rays traveling near the edge of the visual image-forming portion of the eye (also known as "peripheral rays") have less visual significance than light rays traveling closer to the center of the pupil. Therefore, the central optical zone does not need to be larger than the pupil diameter of the eye to be effective. Considering the Stiles-Crawford effect, it is generally desirable that the radius of the central optical zone of the lens be no more than 1 mm smaller than the radius of the wearer's pupil (e.g., 2 mm in diameter).

[0013] As is understood in the art, lenses are not typically custom-made for the wearer. Therefore, lenses can be designed such that the diameter of the central area of ​​the lens is no more than 1 mm smaller than the normal (i.e., average) pupil diameter of the selected population.

[0014] One aspect of the present invention relates to an ophthalmic lens comprising a central region having at least a first focal power and a peripheral region disposed radially outward of the central region. The peripheral region has additional focal power offset and spatial modulation parameters relative to the at least first focal power. In some embodiments, the diameter of the central region is in the range of 2.0 to 5.0 mm. In some embodiments, the central region is no more than 1 mm smaller than the wearer's pupil. In some embodiments, the central region has a diameter of at least 3 mm. In some embodiments, the central region has a diameter of at least 2.0 mm.

[0015] In some embodiments, the additional power offset is in the range of 0.5 diopters to 5 diopters. The lens may further include a transition region between a central region and a peripheral region, such that the power distribution changes continuously from the optical axis to the outer diameter of the peripheral region. In some embodiments, there is a power step between the central region and the peripheral region.

[0016] In some embodiments, the spatial modulation optical parameter is optical power. In some embodiments, the spatial modulation optical power has multiple maximum and minimum values ​​along a radial dimension, and the maximum and / or minimum values ​​increase as a function of radial position. In some embodiments, the spatial modulation optical power has multiple maximum and minimum values ​​along a radial dimension, and these maximum values ​​have the same diopter value as each other, and the minimum values ​​have the same diopter value as each other.

[0017] In some embodiments, the additional power offset is in the range of 0.5 diopters to 5 diopters. In some embodiments, the peripheral region has a base power, and the power difference between the base power and each maximum power is in the range of 0.05 diopters to 2 diopters.

[0018] Spatial modulation optical parameters can be light scattering or light transmission.

[0019] The lens can be a contact lens. The central area may have only a single power.

[0020] In some embodiments, the peripheral region is characterized by a smoothly varying focal length distribution. In other embodiments, the peripheral region is characterized by a focal length distribution with one or more discontinuities between a minimum focal length and a maximum focal length.

[0021] In some embodiments, the fundamental power is uniform across the peripheral region. In other embodiments, the fundamental power increases as a function of the radial position across the peripheral region. The lens may be rotationally symmetric.

[0022] These and other aspects of the invention will become apparent upon review of the following detailed description and the appended claims.

[0023] It should be understood that a multi-zone contact lens is a type of contact lens in which different parts or areas of the lens have different optical parameters or functions, such as different refractive powers. A multifocal contact lens is a subclass of multi-zone contact lenses, characterized in that the central area of ​​the lens approximately corresponds to the normal pupil diameter and has at least two areas with different refractive powers, corresponding to objects at different distances (e.g., corresponding to near vision and far vision). A multifocal lens (simultaneously) provides the wearer with two images and may provide transition areas between the areas.

[0024] The term "optical parameters" is defined herein as properties of a lens that affect the image quality formed by the lens. Optical parameters include, for example, optical power, transparency, aberrations (e.g., including higher-order aberrations), or scattering. Modulation can be achieved, for example, by altering surface curvature, refractive index, surface texture, and material properties.

[0025] The term "spatial modulation" is defined herein as a variation over a given distance (i.e., radial and / or circumferential), such as along the surface of a lens or within the lens itself. Spatial modulation optical parameters have multiple maximum and minimum values ​​over a given distance. The maximum (or minimum) values ​​can be equal or different. Spatial modulation optical parameters reduce the lens's ability to form a high-quality image due to local variations in lens characteristics. For example, spatial modulation of optical parameters can include variations in the lens's optical power, aberration content, light transmission (e.g., the introduction of local translucent inclusions, surface textures, films, or coatings), or light scattering (e.g., the introduction of local scattering inclusions, surface textures, films, or coatings). Scattering may occur due to light absorption and re-emission or due to specular or diffuse reflection. For example, the spatial modulation of optical power can be described using a power distribution.

[0026] As used herein, the terms "greater" and "additional focal length offset" refer to an identified value (e.g., optical power) that is much more positive or less negative than a specified reference value. For example, peripheral focal length may be greater than central focal length. Alternatively, it may be stated that peripheral focal length has an additional focal length offset relative to central focal length. Attached Figure Description

[0027] Figure 1A This is a schematic plan view of an example of an ophthalmic lens according to various aspects of the present invention;

[0028] Figure 1B It is along Figure 1A The line 1B-1B cut Figure 1A A schematic cross-sectional view of the lens;

[0029] Figure 2A An example of the power distribution of an ophthalmic lens is shown, in which changes in optical power are used to achieve spatial modulation of optical parameters in the peripheral region;

[0030] Figure 2B An example of the characteristics of the power distribution is shown, which can be varied to balance the effectiveness of myopia progression inhibition and the likelihood of the wearer experiencing visual impairment.

[0031] Figure 2C Another example of the power distribution of an ophthalmic lens is shown, where spatial modulation of optical parameters in the peripheral region is achieved using radial variations in optical power; and

[0032] Figure 3 An example of a lens is shown, in which spatial modulation of the optical parameters in the peripheral region is achieved by using variations in optical parameters other than optical power. Detailed Implementation

[0033] Various aspects of the invention will be further described with reference to specific embodiments. It should be understood that these examples are given by way of illustration and are not intended to limit the scope of the claims to the specific examples.

[0034] Figure 1A IB is a schematic diagram illustrating examples of ophthalmic lenses according to various aspects of the present invention.

[0035] Ophthalmic lens 100 includes an optical axis OA, a central region 110, and a peripheral region 120. Although the lens shown is circularly symmetrical and has an optical axis OA aligned with the lens's mechanical axis, deviations from this arrangement are possible. Ophthalmic lens 100 is shown as a contact lens; however, lenses according to various aspects of the invention can be implemented as other ophthalmic lenses that remain stationary relative to the eye. For example, the lens can be a corneal inlay, a corneal-only lens, an intraocular lens, or other such ophthalmic lenses.

[0036] The central region 110 has at least a first focal power. The central region can have any suitable focal power distribution and includes at least one area that provides correction for hyperopia. For example, the central region can have only a single focal power, a progressive focal power design, or a multifocal design.

[0037] As described above, since progressive myopia most commonly affects children and young adults, the diameter of the central optical region 110 of the lens according to various aspects of the invention is generally greater than about 3 mm to reasonably ensure that the central region is larger than the wearer's pupil under illumination conditions. However, when light travels toward the retina, light passing near the edge of the visual image-forming part of the eye has less visual significance than light traveling closer to the center of the pupil. Therefore, the central optical region does not need to be equal to or larger than the pupil diameter to be effective. Considering the Styles-Crawford effect, it is generally desirable that the central optical region be no more than 1 mm smaller than the wearer's pupil diameter. For example, the diameter of the central region may be at least 2.0 mm, or at least 3.0 mm, or at least 4.0 mm. The diameter of the central region is generally in the range of 2.5 to 5.0 mm and is chosen (in part) to avoid visual disturbance to a given population under selected illumination conditions.

[0038] The peripheral region 120 is radially outward from the central region. The peripheral region has an additional focal length offset 115 relative to at least a first focal length. For example... Figure 2AAs illustrated in the embodiments, the offset can be achieved by a step in focal power at the edge of the central region; however, in some embodiments, a transition region can exist between the central and peripheral regions, such that the focal power distribution changes continuously from the optical axis to the outer diameter of the peripheral region, allowing the offset to be achieved by a more gradual increase in focal power. The transition region can be a non-optically smooth surface feature. Regardless of whether the offset is achieved by a step or a more gradual increase, discontinuities in the focal power distribution typically exist at the edge of the central region. The additional focal power offset typically provides hyperopic vision correction relative to the focal power in the central region. The focal power in the peripheral region is typically greater than any focal power present in the central region.

[0039] In addition to the additional power shift, the peripheral region is suitable for having spatially modulated optical parameters. As mentioned above, spatially modulated optical parameters reduce the lens's ability to form a high-quality image due to local variations in lens characteristics. For example, embodiments of lenses according to various aspects of the invention may include spatial modulation of one or more of the following optical parameters: optical power, optical aberration, light transmission (e.g., using a translucent inclusion), or light scattering (e.g., using a scattering inclusion).

[0040] Under nominal accommodation conditions, the peripheral region provides myopic defocus due to the additional focal power shift described above for suppressing myopia progression; however, if the wearer's eye deviates from the nominal value, resulting in peripheral hyperopic focus, the spatial modulation of the optical parameters in the peripheral region will continue to provide suppression of myopia progression.

[0041] Furthermore, for wearers with a lower response to suppressing myopia progression caused by peripheral defocus, spatial modulation of optical parameters provides an alternative mode of action for suppressing progression.

[0042] The central area is designed to achieve optimal vision correction using conventional techniques. Typically, achieving optimal vision correction means that the central area corrects for farsighted vision and is free from spatial modulation of optical parameters.

[0043] Figure 2A An example of the lens power distribution is shown, where spatial modulation of optical parameters in the peripheral region is achieved using variations in optical power. The radial power distribution of the peripheral region 220 includes multiple maximum values ​​122a and minimum values ​​122b. That is, the power is modulated in the radial direction to achieve a variation in power along the peripheral region. The radial power can be altered using local variations in surface curvature or refractive index.

[0044] The radial focal length distribution in the peripheral region can have any shape, including both maximum and minimum values. For example, the focal length distribution can be, for instance... Figure 2AThe smooth transition or shape shown may include a discontinuous transition between regions of higher and lower focal length. The shape may include sinusoidal portions, linear portions, or other configurations.

[0045] The fundamental focal length in the peripheral region can be uniform in the radial direction, where spatial modulation causes a shift from the fundamental focal length. Alternatively, the fundamental focal length can vary (increase or decrease) in the radial direction, where spatial modulation causes a shift from the fundamental focal length at a given location.

[0046] like Figure 2B As shown, various features of the power distribution of lenses with spatially modulated power distribution in the peripheral region are selected to achieve myopia progression suppression. Typically, the power distribution is chosen to balance the effectiveness of myopia progression suppression with visual impairment. The suppression of myopia progression and the presence of visual impairment can be modeled using optical design software and / or through clinical testing.

[0047] The additional power offset between the primary power and the fundamental power in the peripheral region is typically in the range of 0.5 diopters to 5 diopters. For example, the offset could be 3.0 diopters.

[0048] The difference in refractive power between the basic and maximum values ​​in the peripheral region is typically in the range of 0.05 diopters to 2 diopters, and in some cases, in the range of 0.25 diopters to 1.5 diopters. In some cases, in a given radial distribution, all maximum values ​​have the same refractive power, and all minimum values ​​have the same refractive power; however, in some embodiments (see...) Figure 2C The maximum and / or minimum values ​​in a given radial distribution can have different diopter powers.

[0049] Figure 2C Another example of the power distribution of an ophthalmic lens is shown, in which spatial modulation of the optical parameters of the peripheral region 230 is achieved using radial optical power; however, the maximum and minimum refractive power values ​​vary as a function of radial position. Specifically, in the illustrated embodiment, the maximum and minimum refractive power values ​​increase as a function of radial position. In such a lens, the decreasing variation in radially inward position results in less visual disturbance (i.e., directing light artifacts to the visual portion of the retina), while the increasing variation in radially outward position increases utility (i.e., inhibiting myopia progression).

[0050] Figure 2A-2C The embodiments can be rotationally symmetric or can have spatial modulation of focal power in the circumferential direction. According to various aspects of the invention, the lens can have spatial modulation in the radial and / or circumferential directions.

[0051] Figure 3This is a schematic diagram of an example of lens 300, in which spatial modulation of the optical parameters of the peripheral region is achieved using changes in optical parameters rather than optical power. For example, changes can be achieved using variations in optical aberrations, variations in light transmission (e.g., using translucent inclusions), or light scattering (e.g., using scattering inclusions). Except for the type of optical parameters being varied, lens 300 is the same as lens 100 described above.

[0052] Similar to the focal length of spatial modulation as described above, reference Figure 3 The spatial modulation of the other optical parameters reduces the lens's ability to form a high-quality image, thereby inhibiting myopia progression. However, the advantage of using spatially modulated power is that, although power modulation reduces image quality at any given focal plane, the resulting lens provides a depth of field that can offer visual advantages.

[0053] exist Figure 3 In this context, local changes are represented by x. It should be understood that although local changes occur in... Figure 3 The optical parameters are shown as non-rotationally symmetric, but in other embodiments, this spatial modulation of the optical parameters can be rotationally symmetric.

[0054] Hydrogel contact lenses are typically packaged in a buffered saline solution. If desired, the packaging solution may include pharmaceutical agents that reduce myopia progression. Representative pharmaceutical formulations include muscarinic preparations such as atropine, pilocarpine, pirenzepine and their derivatives and salts.

[0055] If needed, contact lenses can be used to deliver other therapeutic agents, such as various pharmaceutical preparations, drugs, or active agents for the treatment, inhibition, and / or prevention of a variety of diseases and conditions. Examples include: glaucoma treatment agents, such as brimonidine and its salts; antihistamines such as ketotifen, phenylephrine, and their salts; and vitamins, antioxidants, and nutritional supplements, including vitamins A, D, and E, lutein, zeaxanthin, taurine, fatty acids, etc.

[0056] Although various embodiments have been described in detail herein, it will be apparent to those skilled in the art that various modifications, additions, substitutions, etc., can be made without departing from the spirit of the invention, and therefore these are considered to be within the scope of the invention as defined in the following claims.

Claims

1. An ophthalmic lens, comprising: The central region has at least a first focal length that forms a step; as well as A peripheral region is disposed radially outside the central region, the peripheral region having an additional focal length offset relative to the at least first focal length that forms a focal length step between the central region and the peripheral region, and the peripheral region having a smoothly varying spatially modulated optical focal length distribution having a plurality of maximum values ​​and a plurality of minimum values, the magnitudes of the maximum values ​​and the minimum values ​​increasing relative to the additional focal length offset as a function of radial position.

2. The lens according to claim 1, wherein, The diameter of the central region is at least 3 mm.

3. The lens according to claim 1, wherein, The central area is no more than 1 mm smaller than the wearer's pupil.

4. The lens according to claim 1, wherein, The diameter of the central region is at least 2.0 mm.

5. The lens according to claim 1, wherein, The diameter of the central region is in the range of 2.0 to 5.0 mm.

6. The lens according to claim 1 or 5, wherein, The additional focal length offset is in the range of 0.5 diopters to 5 diopters.

7. The lens according to claim 1 further includes a transition region located between the central region and the peripheral region, such that the power distribution of the outer diameter from the optical axis to the peripheral region changes continuously.

8. The lens according to claim 6, wherein, The peripheral region has a basic focal power, and the focal power difference between the basic focal power and each maximum value is in the range of 0.05 diopters to 2 diopters.

9. The lens according to claim 1, wherein, The lens is a contact lens.

10. The lens according to claim 1, wherein, The central region has a single focal length.

11. The lens according to claim 8, wherein, The basic focal length is uniform across the peripheral region.

12. The lens according to claim 8, wherein, The basic focal length increases as a function of radial position across the peripheral region.

13. The lens according to claim 1, wherein, The lens is rotationally symmetrical.

14. The lens according to claim 1, wherein, The lens is a hydrogel contact lens packaged in combination with a buffered saline solution containing an agent that reduces the progression of myopia.

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