RU2575048C2 - Ophthalmic lens design for myopia control - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: in accordance with the first version, an ophthalmic lens for delay of myopia development comprises a convex surface with central optic, peripheral and rim zones and a concave surface contacting an eye. The central optic zone comprises an inner disk and a number of ring zones, and a lens strength in any point of the optic zone is determined by subtracting an eye strength consistent with pre- and post-orthokeratology corneal topography or wave front data. According to the second version, at least a part of the optic zone in the lens is described by equation: strength = 0.486x⁶-5.8447x⁵+27.568x⁴-65.028x³+81.52x²-51.447x+12.773, where x is a radial distance from the lens centre.

EFFECT: delay or arrest of myopia development with using the corneal topography data or wave front measurements.

11 cl, 6 dwg

Description

BACKGROUND OF THE INVENTION

The present invention relates to constructions and methods for preventing, stopping and slowing the development of myopia.

Myopia, also known as myopia, is a pathological condition of the light-refracting system of the eye, in which the total optical power of the eye is too high (too large), which leads to the focusing of light rays from distant sources in front of the retina. The patient perceives the condition as the blur of distant objects, while the degree of blur is directly related to the severity of myopia. The condition is often first diagnosed in childhood, usually at school age. The progression or increase in the severity of myopia is usually observed in patients before puberty.

US Pat. No. 6,045,578 proposes methods for using axial longitudinal spherical aberration (LSA) in contact lens designs as a measure to slow the development of myopia. However, the approach proposed in it does not take into account the specific characteristics of the wavefront / refractive power of an individual patient’s eye or group-averaged data, as well as changes in pupil size associated with short-range work.

In US patent No. 7025460 proposed methods of changing the curvature of the image field (off-axis variation of the focal point) as a measure of slowing the development of myopia. The mathematical apparatus used in the framework of this approach operates with the concept of “extended equation for second-order curves”, which assumes that polynomial terms of even orders are additionally introduced into equations for simple second-order curves. These equations with additional polynomial terms are processed in such a way that the surface shape of the contact lens of the described design provides the required degree of curvature of the image field.

In US patents No. 2003/0058404 and 2008/0309882 a method for measuring the wavefront of the eye and individual correction of the wavefront of the eye to slow the development of myopia is proposed. Changes in pupil size associated with working at close range were not considered when developing this design.

Patent No. EP 1853961 proposes measuring the wavefront before and after working at close range. Then, the detected changes in the wavefront aberrations are corrected using individually selected contact lenses. Data on groups or populations were not taken into account when developing designs for controlling eye growth.

Orthokeratology Alters Aberrations of The Eye; Optometry and Vision Science, May 2009. This paper discusses high-order aberrations associated with orthokeratology.

Thus, a more comprehensive approach to slowing or stopping the development of myopia is needed. It is this approach that is considered in this application.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a method and construction for the manufacture of ophthalmic lenses for controlling and slowing the development of myopia include the use of corneal topography data for a corrected eye. Such ophthalmic lenses include, for example, contact lenses, intraocular lenses, corneal implants and corneal pads.

In another aspect of the present invention, a method and structure for manufacturing ophthalmic lenses for controlling and slowing the development of myopia include the use of wavefront data for the corrected eye.

In yet another aspect of the present invention, the construction of ophthalmic lenses made in accordance with the methods of the present invention includes a convex surface with a central optical zone surrounded by a peripheral zone, which in turn is surrounded by an edge zone, and a concave surface in contact with the eye of the patient wearing the lens ; said central optical zone comprises an internal disk and a plurality of annular zones; and the optical power of the lens at any location of the optical zone is obtained by subtracting the optical power of the eye before the orthokeratology procedure and the optical power after the orthokeratology procedure; lenses made in accordance with this design are configured to control or slow the development of myopia.

In another aspect of the present invention, a method for constructing an ophthalmic lens includes the steps of obtaining data on the topography of the cornea before and after the orthokeratology procedure, converting data on the topography of the cornea into radial optical power maps, subtracting the card for the cornea after the orthokeratology procedure from the card for the cornea prior to the orthokeratology procedure and the formation of the optical power profile of the lens.

In another aspect of the present invention, a method for constructing an ophthalmic lens design includes the steps of obtaining wavefront data before and after the orthokeratology procedure, converting wavefront data to radial optical power maps, subtracting the cornea card after the orthokeratology card from the cornea card before the orthokeratology procedure and forming a lens power profile.

In yet another aspect of the present invention, data for an entire population is taken into account.

In yet another aspect of the present invention, data for a subgroup of the entire population are taken into account.

In yet another aspect of the present invention, data for an individual patient is considered.

In yet another aspect of the present invention, the data used is the result of averaging multiple files.

In another aspect of the present invention, the optical power profile for the design of the lens under development is calculated by averaging over all meridians to obtain an axisymmetric shape.

In another aspect of the present invention, the optical power profile for the design of the lens under development is calculated by averaging over individual meridians to obtain an axisymmetric shape.

In yet another aspect of the present invention, methods for constructing lenses to slow the development of myopia are encoded in the form of instructions, such as machine instructions, and entered as a program into a computer.

In another aspect of the present invention, the subject invention includes executable instructions for constructing lenses to slow the progression of myopia; The method of the invention includes converting eye characteristics on the topography of the cornea into a radial optical power map, forming a lens optical power profile and using the obtained optical power profile to construct a lens for a lens having a convex surface with a central optical zone surrounded by a peripheral zone, which in turn surrounded by a marginal zone, and a concave surface in contact with the eye of the patient wearing a lens; wherein the central optical zone comprises an internal disk and a plurality of annular zones; the optical power of the lens at any location in the optical zone is obtained by subtracting the optical power of the eye before the orthokeratology procedure and the optical power after the orthokeratology procedure.

In another aspect of the present invention, the subject invention includes executable instructions for constructing lenses to slow the progression of myopia; the method of the invention includes converting eye-characteristic wavefront data into a radial optical power map, forming a lens optical power profile and using the obtained optical power profile to construct a lens for a lens having a convex surface with a central optical zone surrounded by a peripheral zone, which in turn is surrounded a marginal zone, and a concave surface in contact with the eye of the patient wearing a lens; wherein the central optical zone comprises an internal disk and a plurality of annular zones; the optical power of the lens at any location in the optical zone is obtained by subtracting the optical power of the eye before the orthokeratology procedure and the optical power after the orthokeratology procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1 shows averaged maps of corneal topography for a group of 26 patients prior to the orthokeratology procedure.

In FIG. Figure 2 shows averaged maps of the topography of the cornea for a group of 26 patients after the orthokeratology procedure.

In FIG. Figure 3 shows the difference between the averaged maps of the topography of the cornea after and before the orthokeratology procedure for a group of 26 patients who underwent the orthokeratology procedure.

In FIG. Figure 4 shows the difference between the average maps of the topography of the cornea after and before the orthokeratology procedure for a group of 26 patients who underwent the orthokeratology procedure, cut to a diameter of 6 mm.

In FIG. 5 shows the optical power profile of a lens structure in accordance with the present invention.

In FIG. 6 shows the envelope of the optical power profiles of the lens structure, constructed on the basis of scaling averages over all meridians in the above example in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Orthokeratology (sometimes also called refractive therapy of the cornea) is a procedure for selecting hard contact lenses for purposefully changing the shape of the central part of the cornea of the eye. Reducing the curvature of the central part of the cornea of the eye leads to a decrease in the optical power of the cornea and thereby the entire eye. This has the effect of reducing the severity of myopia of the eye. As a rule, specially designed hard contact lenses are worn at night, during sleep, and removed in the morning. The pressure created by such a rigid lens on the cornea during sleep, helps to temporarily flatten the central part of the cornea. This flattening leads to a decrease in myopia, which gradually regresses (that is, the cornea returns to its normal form) over the next 1-3 days. Using an orthokeratology procedure, the patient puts on hard contact lenses for sleep every 1-3 nights, depending on the speed of restoration of the shape of the cornea, and thereby maintains a reduced degree of myopia during wakefulness without the need to wear any contact lenses or glasses.

An unexpected consequence of orthokeratology was a decrease in the rate of myopia in patients using this form of correction of myopia. Research Cho et al. (LORIC study) and Walline et al. (CRAYON study) demonstrated that in patients wearing orthokeratological lenses, not only the severity of myopia decreases, but also the rate of its development (i.e. eye growth). A possible explanation for this decrease in the rate of myopia is optical changes caused by the procedure of orthokeratology in the cornea. Orthokeratology effectively changes the optical properties of the cornea in such a way that the optical power of its central part becomes more negative (less positive), and the optical power of its peripheral part becomes more positive (less negative).

In one preferred embodiment, the methods of the present invention include the use of corneal topography data for the design and manufacture of contact lenses, which can be used to treat, slow and sometimes stop the development of myopia. Corneal topography data is obtained from a patient using a video keratoscope such as a Keratron or Keratron Scout (Optikon 2000; Rome, Italy). The obtained topographic data can be presented in several formats. A preferred format for the purposes of the present invention is to present the cornea as a data set on optical power.

In FIG. 1 shows the averaged data of the optical power of 26 eyes obtained using a video keratoscope prior to the orthokeratology procedure, and FIG. 2 shows the results of video keratoscopy of the same 26 eyes after the orthokeratology procedure. The change in the optical power of the cornea can be obtained by subtracting the optical power of the cornea before and after the orthokeratology procedure. On such a map of the optical power change, a shift in the optical power of the central part in the negative direction (i.e., blue colors) and a shift in the optical power of the peripheral part in the positive direction (i.e., red color), as shown in FIG. 3. Such a difference map is the basis for the methods for developing optical power profiles described in this application, which allow controlling the rate of myopia development.

In one embodiment, such cards are centered around the axis of the video keratoscope (the axis on which the video keratoscope measures the shape of the cornea), however, in the preferred embodiment, they can also be counted and centered around the pupil of the eye (i.e., the entrance of the eye in the plane of the cornea) . The pupil axis and the axis of the video keratoscope rarely coincide. Under the conditions of the optical structure, it is preferable to center the optical structure along the center axis of the pupil inlet.

The next step in the process of designing a soft lens is to reduce the two-dimensional difference map of optical power to the average change in optical power over all meridians, which gives a symmetric map of average optical power. In FIG. 4, this procedure is illustrated for a two-dimensional difference map of optical power limited by a diameter of 6 mm.

In an alternative embodiment, the obtained difference map of optical power is reduced to a two-dimensional difference map of optical power by averaging the change in optical power along each meridian, while individual meridians are averaged separately to obtain a non-axisymmetric map of average optical power.

In a preferred embodiment, it is desirable to expand the optical power profile of the lens structure beyond the limits of 6 mm to 8 mm and create an optical power profile that provides the best clinical result and avoids the introduction of excessive additional positive optical power to the patient. In a preferred embodiment, the positive optical power is first reduced and then brought to a constant level.

In a preferred embodiment, the construction of ophthalmic lenses made in accordance with the methods of the present invention includes a convex surface with a central optical zone surrounded by a peripheral zone, which in turn is surrounded by an edge zone, and a concave surface in contact with the eye of the patient wearing the lens; wherein the central optical zone comprises an internal disk and a plurality of annular zones; and the optical power of the lens at any location of the optical zone is obtained by subtracting the optical power of the eye before the orthokeratology procedure and the optical power after the orthokeratology procedure; lenses made in accordance with this design are configured to control or slow the development of myopia.

In FIG. 5 shows an optical power profile for a preferred embodiment of the present invention. In this preferred embodiment, said central optical zone comprises an inner disk with a range of possible diameters from 0 to 2 mm and a preferred diameter of about 1.5 mm; a first annular zone with an outer diameter of from 6.0 to 7.0 mm and a preferred diameter of approximately 6.5 mm; surrounding the first annular zone, a second annular zone with an outer diameter of from 7.25 to 7.75 mm and a preferred diameter of approximately 7.5 mm; and a third annular zone surrounding the second annular zone with an outer diameter of from 7.5 to 8.5 mm and a preferred diameter of about 8 mm.

Shown in FIG. 5 optical power is based on data processing for the average cumulative. The given strengths should be added to those recommended by the patient for the correction of distant vision. The optical power in the central disk of the optical zone is substantially constant; the optical power in the first annular zone, with a diameter of 4 mm, increases in the direction of positive power to a range from +0.5 to +1.5 diopters, with a preferred value of approximately +1.0 diopters, and with a diameter of 6.5 mm increases direction of positive force up to a range of +1.5 to +5.5 D, with a preferred value of approximately +3.4 D; the optical power in the second annular zone smoothly decreases from the optical power at the boundary of the first annular zone to the optical power in the range from about +1.5 to +4.5 D, with a preferred value of about +3.0 D; the optical power in the third annular zone remains substantially constant and approximately equal to the optical power at the boundary of the second annular zone.

Recommended patient optical power profiles for correcting far vision, substantially other than -3.00 D, may require scaling of the optical power profile. In FIG. 6 shows a preferred embodiment of a scaled envelope of the obtained optical power curves, which can be calculated and used to construct the lens based on the averaged data given above. Thus, for the lens construction constituting the subject of the present invention, it is possible to create a family of optical power profiles embedded in the structure. The latter are created by proportionally multiplying by a scaling factor for each point of the aperture; wherein said scaling factor is in the range of 0.25 to 4, and is preferably in the range of 0.5 to 1.5.

Preferred steps in the process of forming an optical power profile for lens construction in accordance with this method include:

1) obtaining and averaging topographic maps of the optical power of the cornea for the eyes before the orthokeratology procedure,

2) obtaining and averaging maps of the optical power of the cornea for the eyes after the orthokeratology procedure,

3) subtraction of the card for the cornea before the orthokeratology procedure from the card for the cornea after the orthokeratology procedure,

4) averaging over all meridians to obtain an axisymmetric map of optical power,

5) alternatively, averaging over individual meridians to obtain a non-axisymmetric map of optical power,

6) trimming the received cards to a convenient uniform diameter,

7) it is not necessary to expand the obtained profile to a larger diameter by reducing the positive optical power and then bringing it to a constant level,

8) it is not necessary to form the envelope of the optical power profiles by proportional scaling.

In an alternative embodiment, the methods of the present invention include using wavefront data to create and produce contact lenses that can be used to treat, slow, and sometimes completely stop the development of myopia. The wavefront data of a patient’s eyes is collected using a wavefront sensor, for example, a COAS complete ophthalmic analysis system (Wavefront Sciences Inc, Albuquerque, New Mexico, USA). The obtained wavefront data are usually presented as coefficients in the expansion in Zernike polynomials, but can also be represented as a set of wavefront heights at points with specified Cartesian or polar coordinates. The preferred Zernike coefficient designation system is set forth as the American Optical Society (OSA) method and is fixed in the ANSI Z80.28 standard.

Preferred steps in the process of forming an optical power profile for lens construction in accordance with this method include:

1) obtaining and averaging wavefront maps for the eyes prior to the orthokeratology procedure. Each wavefront is converted into an optical power map by evaluating the radial angular coefficients in the direction of the z axis, defined as the axis located in the front to back direction, for example, along the visual axis through the center of the pupil,

2) obtaining and averaging wavefront maps for the eyes after the orthokeratology procedure. Each wavefront is converted into an optical power map by evaluating the radial angular coefficients in the direction of the z axis, defined as the axis located in the front to back direction, for example, along the visual axis through the center of the pupil,

3) subtraction of the card before the orthokeratology procedure from the card after the orthokeratology procedure,

4) averaging over all meridians to obtain an axisymmetric map of optical power,

5) alternatively, averaging over individual meridians to obtain a non-axisymmetric map of optical power,

6) trimming the received cards to a convenient diameter,

7) it is not necessary to expand the obtained profile to a larger diameter by reducing the positive optical power and then bringing it to a constant level,

8) it is not necessary to form the envelope of the optical power profiles by proportional scaling.

, следующим образом (см. Iskander et al., 2007, прилагается к настоящему документу)In this method, an optical power map is compiled based on a set of estimated Zernike coefficients for the wavefront using Zernike polynomials for optical power, $${\Psi }_j(\rho ,\theta )$$

, as follows (see Iskander et al., 2007, attached to this document)

$$\begin{array}{ccc}& & \end{array}$$

(1)

$$\begin{array}{ccc}& & \end{array}$$

(one)

- коэффициенты в разложении волнового фронта по полиномам Цернике,Where $$c_j$$

- coefficients in the expansion of the wave front in Zernike polynomials,

- радиус зрачка; $$r_{\max }$$

- pupil radius;

$$\begin{array}{ccc}& & \end{array}$$

(2)

$$\begin{array}{ccc}& & \end{array}$$

(2)

as well as

$$\begin{array}{ccc}& & \end{array}$$

(3)

$$\begin{array}{ccc}& & \end{array}$$

(3)

and

Other methods are known to those skilled in the art for generating or calculating optical power values from wavefront data. The size of the pupil is also evaluated either directly from the results of the wavefront measurement, or by independent measurement of the pupil (for example, using a pupillometer). If the pupil size is determined independently of the wavefront measurement, the measurement should be carried out under similar lighting conditions.

The disclosed method for developing lenses for a particular patient is based on individual data for the patient, on average data for a certain subgroup of the population, or on average data for the entire population. The described method can be used to obtain an axisymmetric lens design in which all the meridians of the optical zone are identical, or an axisymmetric lens design in which each meridian is individually selected based on an analysis of the cornea topography or wavefront data before and after the orthokeratology procedure.

Ophthalmic lenses made in accordance with the principles of the present invention have the following structural elements and characteristics:

a) a convex surface with a Central optical zone surrounded by a peripheral zone, which in turn is surrounded by an edge zone, and a concave surface in contact with the user's eye;

b) the optical power of the lens at any location in the optical zone is obtained by subtracting the optical power of the eye before the orthokeratology procedure and the optical power after the orthokeratology procedure.

In another preferred embodiment, ophthalmic lenses made in accordance with the principles of the present invention have the following structural elements and characteristics:

a) the Central optical zone, and the Central optical zone contains an internal disk with a range of possible diameters from 0 to 2 mm and a preferred diameter of approximately 1.5 mm;

b) a first annular zone with an outer diameter of from 6.0 to 7.0 mm and a preferred diameter of approximately 6.5 mm;

c) a second annular zone surrounding the first annular zone with an outer diameter of from 7.25 to 7.75 mm and a preferred diameter of about 7.5 mm;

d) a third annular zone surrounding the second annular zone with an outer diameter of from 7.5 to 8.5 mm and a preferred diameter of about 8 mm.

In another preferred aspect of the present invention, ophthalmic lenses made in accordance with the principles of the present invention have the following structural elements and characteristics:

a) the optical power in the Central disk of the optical zone is essentially constant;

b) the optical power in the first annular zone, with a diameter of approximately 4 mm, increases in the direction of positive force to a range from +0.5 to +1.5 D, with a preferred value of approximately +1.0 D, with a diameter of 6.5 mm increases in the direction of positive force to a range from +1.5 to +5.5 D, with a preferred value of approximately +3.4 D;

c) the optical power in the second annular zone smoothly decreases from the optical power at the boundary of the first annular zone to the optical power in the range from about +1.5 to +4.5 D, with a preferred value of about +3.0 D;

d) the optical power in the third annular zone remains substantially constant and approximately equal to the optical power at the boundary of the second annular zone.

In another preferred aspect of the present invention, ophthalmic lenses made in accordance with the principles of the present invention have the following structural elements and characteristics:

a) the optical power in the Central disk of the optical zone is essentially constant;

b) the optical power in the first annular zone increases in the direction of the positive force, following the corresponding polynomial expression of the 4th or higher order.

In a preferred aspect, the change in optical power in the first annular zone is described by the expression: optical power = 0.486x ⁶ -5.8447x ⁵ + 27.568x ⁴ -65.028x ³ + 81.52x ² -51.447x + 12.773,

where x is the radial distance from the center of the lens.

c) the optical power in the second annular zone decreases from the optical power at the boundary of the first annular zone to the optical power in the range from about +1.5 to +4.5 D, with a preferred value of about +3.0 D;

d) the optical power in the third annular zone remains substantially constant and approximately equal to the optical power at the boundary of the second annular zone.

One skilled in the art will recognize that the optical power in the central optical zone of the lens is the result of the optical forces of the rear surface and the front surface working together. Variations in the optical power described in the method and construction constituting the subject of the present invention can be created due to the front surface of the lens, the rear surface of the lens, or a combination thereof. In a preferred embodiment, the variations in optical power described in the method and construction constituting the subject of the present invention are created due to the front surface of the lens.

Methods for developing ophthalmic lenses based on optical power profile

For the construction of an optical lens for the control of myopia, various data sources can be used, for example, the following:

individual design based on the individual data of an individual patient, or

group-average design based on data for a subgroup of a population (e.g., Asian teens aged 10 to 16), or

population-averaged design based on available data (e.g., all myopia patients).

In addition, the methods that are the subject of the present invention make it possible to obtain both axisymmetric and non-axisymmetric lens designs. When averaging data for all half-meridians taken into account, the obtained average profile can be used to create axisymmetric structures or the retention of available data for each half-meridian allows you to create non-axisymmetric structures. Forms of non-axisymmetric corrections, among other things, include the correction of toric and spherical cylindrical aberrations, as well as spherical cylindrical aberrations taking into account high-order aberrations. Toric aberrations include regular and irregular astigmatism.

The following is an example of a method for developing a lens design in accordance with the principles of the present invention based on averaged data for all half meridians taken into account. This approach gives an axisymmetric lens design.

Method 1

In the first method, maps obtained before and after the orthokeratology procedure are used as a starting point for constructing the lens. The map obtained before the orthokeratology procedure is subtracted from the map obtained after the orthokeratology procedure, and averaging over all meridians is performed. This gives the optical power profile shown in FIG. 5. The obtained optical power profile is then used to construct the lens for a myopia patient who needs a lens power of -3.00 DS to slow the development of myopia. In method 1, the optical power embedded in the lens design in the first annular zone of the central optical zone is mathematically calculated as follows:

optical power = 0.486x ⁶ -5.8447x ⁵ + 27.568x ⁴ -65.028x ³ + 81.52x ² -51.447x + 12.773,

where x is the radial distance to the center of the lens.

The methods that are the subject of the present invention can be implemented as computer-readable codes on a computer-readable medium. The specified computer-readable medium is any data storage device that allows you to store data with their subsequent reading into a computer system. Examples of computer-readable media include read-only memory, random access memory, CD-ROM and DVD, magnetic tape, and optical storage devices. Said computer-readable medium may also be distributed among a group of networked computers so that said computer-readable codes are stored and executed in a distributed environment.

The present invention can be practically implemented using computer programming and development technologies, including computer software, firmware, hardware, as well as any combination or kit thereof. Any such ready-made program, represented as a set of computer-readable codes, can be physically implemented or recorded on one or more computer-readable media, thereby representing a computer program product, i.e. an article made in accordance with the principles of the present invention. Said computer-readable media can be, for example, a hard disk, a floppy disk, an optical disk, a magnetic tape, a semiconductor memory device, such as read-only memory (ROM), etc., or can be any transceiver medium, such like the Internet or any other network or communication system. A product containing computer programs can be obtained and (or) used by running the program directly from one medium, by copying the program from one medium to another medium, or by transferring the program over a network.

Devices in accordance with the principles of the present invention may also be one or more data processing systems, including but not limited to a central processing unit (CPU), memory, storage devices, communication / network connection devices, servers, input / output devices, or any part of one or more data processing systems, including software, firmware, hardware, or any combination or kit that are used in the implementation of the present invention, the formulation as set forth in the claims below.

Information from the user can be entered using a keyboard, mouse, pen, voice, touch screen or other means by which a person can enter data into a computer, including including other programs, such as application programs.

An IT specialist will be able to combine the software described in this application with appropriate general or special purpose computer hardware to create a computer system or subsystem that implements the method that is the subject of the present invention.

These methods, implemented, for example, in machine instructions on a computer-readable medium, are used to obtain the lens designs described above. Designed in accordance with one of the methods described above, lens designs are used to make lenses. Preferably, said lenses are contact lenses. Typical materials that can be used to make soft contact lenses include, but are not limited to, silicone elastomers, silicone-containing macromers, which include, but are not limited to, the macromers described in US Pat. Nos. 5,371,147, 5,314,960 and 5,057,578, which are incorporated herein by reference in their entirety. , hydrogels, silicone-containing hydrogels, and the like, as well as combinations thereof. A more preferred material is siloxane or a material containing siloxane groups, including but not limited to macromers of polydimethylsiloxane, methacryloxypropylsiloxanes and mixtures thereof, silicone hydrogel or hydrogel. Examples of such materials include, but are not limited to, aquafilcon, ethafilcon, genfilcon, lenefilcon, senofilcon, balafilcon, lotrafilcon, halifilcon and narafilcon.

Any suitable methods may be used to polymerize the lens material. For example, lens material can be placed in a mold and polymerized using thermal, radiation, chemical, electromagnetic polymerization, etc., or a combination thereof. Preferably, the manufacture is carried out using ultraviolet radiation or the full spectrum of visible radiation. More specifically, the exact parameters of the polymerization of the lens material depend on the selected material and the manufactured lens. The corresponding processes are described in US patent No. 4495313, 4680336, 4889664, 5039459 and 5540410, which are fully incorporated into this application by reference.

The formation of contact lenses in the framework of the present invention can be carried out in an appropriate manner. One such method is the manufacture of a mold insert on a lathe. Mold inserts are in turn used to create molds for casting. Then, the corresponding lens manufacturing material is placed in the casting mold, and the material is pressed and polymerized to produce the lenses of the present invention. One skilled in the art will appreciate that the lenses of the present invention can be made using other known methods.

EXAMPLES

Example 1 (alleged)

In a long-term study, comparing the axial length (eye growth) and autorefraction of an age-matched group of children with patients aged 6 to 14 years, patients of one group wore contact lenses made in accordance with the method and design that are the subject of the present invention, and patients control groups wore standard contact lenses or glasses. Patients of the first group wore lenses with the design and optical power profile disclosed in this application.

a) the optical power in the Central disk of the optical zone is essentially constant;

b) the optical power in the first annular zone, with a diameter of approximately 4 mm, increases in the direction of positive force to a range from +0.5 to +1.5 D, with a preferred value of approximately +1.0 D, with a diameter of 6.5 mm increases in the direction of positive force to a range from +1.5 to +4.5 D, with a preferred value of approximately +3.4 D;

c) the optical power in the second annular zone decreases from the optical power at the boundary of the first annular zone to the optical power in the range from about +1.5 to +4.5 D, with a preferred value of about +3.0 D;

d) the optical power in the third annular zone remains substantially constant and approximately equal to the optical power at the boundary of the second annular zone.

The optical power of the lens in this example is described as follows:

a) the optical power in the Central disk of the optical zone is essentially constant;

b) the optical power in the first annular zone increases in the direction of the positive force, following the corresponding polynomial expression of the 4th or higher order;

c) in a preferred aspect, the change in optical power in the first annular zone is described by the expression: optical power = 0.486x ⁶ -5.8447x ⁵ + 27.568x ⁴ -65.028x ³ + 81.52x ² -51.447x + 12.773,

where x is the radial distance from the center of the lens.

d) the optical power in the second annular zone decreases from the optical power at the boundary of the first annular zone to the optical power in the range from about +1.5 to +4.5 D, with a preferred value of about +3.0 D;

e) the optical power in the third annular zone remains substantially constant and approximately equal to the optical power at the boundary of the second annular zone.

After observing for six months to one (1) year, the study participants from the group wearing contact lenses made in accordance with the method and design that are the subject of the present invention had 60-80% lower or lower average group growth rate of the eye compared with patients in the control group according to the results of measuring changes (increase) in axial length or changes (myopic shift) autorefraction for the same period of time.

Claims (11)

1. Ophthalmic lens to slow the development of myopia, containing:
a) a convex surface with a Central optical zone surrounded by a peripheral zone, which is additionally surrounded by an edge zone, and a concave surface in contact with the eye of the patient wearing a lens;
b) a central optical zone comprising an internal disk and a plurality of annular zones; and the optical power of the lens at any location in the optical zone is represented by subtracting the optical power of the eye based on the topography of the cornea or wavefront data obtained before the orthokeratology procedure and after the orthokeratology procedure; made in accordance with this design, the lens is made with the ability to control and slow the development of myopia. 2. The lens of claim 1, wherein the inner disk has a diameter of less than 2 mm. 3. The lens of claim 1, wherein the optical power of the inner disk is substantially constant. 4. The lens of claim 1, wherein the first annular zone has an outer diameter in the range of 6.0 to 7.0 mm. 5. The lens according to claim 1, in which the optical power in the first annular zone with a diameter of 4 mm is in the range from +0.5 to +1.5 D. 6. The lens according to claim 1, in which the optical power in the first annular zone with a diameter of 6.5 mm is in the range from +1.5 to +5.5 D. 7. The lens of claim 1, wherein the second annular zone surrounding the first annular zone has an outer diameter in the range of 7.25 to 7.75 mm. 8. The lens according to claim 1, in which the optical power in the second annular zone smoothly decreases from the optical power at the boundary of the first annular zone to the optical power in the range from +1.5 to +4.5 D. 9. The lens of claim 1, wherein the third annular zone surrounding the second annular zone has an outer diameter in the range of 7.5 to 8.5 mm. 10. The lens of claim 1, wherein the optical power in the fourth annular zone is substantially constant and approximately equal to the optical power at the boundary of the second annular zone. 11. An ophthalmic lens to slow the development of myopia, in which at least part of the optical zone is described by the following equation: Optical power = 0.486x ⁶ -5.8447x ⁵ + 27.568x ⁴ -65.028x ³ + 81.52x ² -51.447x + 12.773 where x is the radial distance from the center of the lens.

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