WO2023072031A1

WO2023072031A1 - Posterior chamber type progressive multi-focus phakic intraocular lens

Info

Publication number: WO2023072031A1
Application number: PCT/CN2022/127253
Authority: WO
Inventors: 赵紫微; 王明坤; 张明瑞; 霍胜斌
Original assignee: 天津世纪康泰生物医学工程有限公司
Priority date: 2021-10-25
Filing date: 2022-10-25
Publication date: 2023-05-04
Also published as: CN114010371A

Abstract

A posterior chamber type progressive multi-focus phakic intraocular lens (103), made of a soft transparent hydrophilic or hydrophobic acrylic material, comprising an optical zone (203), a support portion (202) at the edge of the optical zone (203), and support loops (201), and implanted behind the iris (102) and in front of the natural lens (104). The optical zone (203) of the intraocular lens (103) has both a far vision zone (401) and a near vision zone (402), and the diopter smoothly transitions from the far vision zone (401) to the near vision zone (402) in a progressive manner. One of the front surface and the rear surface of the optical zone (203) is generally a spherical surface or an aspheric surface, and the other surface is a progressive free-form surface. After the intraocular lens (103) is implanted, myopia and presbyopia of middle-aged and elderly people can be corrected at the same time, so that the middle-aged and elderly people having requirements for mobile phones, reading and entertainment can take off glasses truly.

Description

A posterior chamber phakic progressive multifocal intraocular lens

This application claims the priority of the Chinese patent application submitted to the China Patent Office on October 25, 2021, with the application number 202111238487.3, and the title of the invention is "A Posterior Chamber Type Phakic Progressive Multifocal Intraocular Lens", the entire content of which is incorporated by reference incorporated in this application.

technical field

The invention relates to the technical field of manufacturing phakic intraocular lenses, in particular to a design method for posterior chamber type phakic progressive multifocal intraocular lenses.

Background technique

People often think that people with myopia will not have presbyopia, which is wrong. Presbyopia will also occur in myopia, and the time of occurrence is no different from that of emmetropia. However, due to the refractive physiological characteristics of myopia, the symptoms will appear later. But as the degree of presbyopia continues to deepen, myopia also needs a pair of presbyopia glasses, that is to say, people with myopia need two pairs of glasses to see far and near, which is more troublesome than normal presbyopia. In order to realize that the human eye can see far and near clearly at the same time, bifocals, trifocals and progressive multifocal glasses have appeared successively. However, there are many situations in life where it is inconvenient or not recommended to wear glasses, such as entering the In the normal room, water mist will form on the surface of the glasses, and repeated removal and wearing of the glasses will deform the glasses and affect the wearing effect.

At present, phakic intraocular lens implantation can treat refractive errors and is widely used clinically. It is a relatively effective and safe operation for correcting moderate to high myopia. The present invention designs an implantable progressive multifocal intraocular lens. The diopter of the intraocular lens gradually increases from top to bottom, and the eyes can see objects at long distances, intermediate distances, and near distances from different areas. The intraocular lens implantation operation is the same as the phakic intraocular lens implantation operation. The operation is relatively simple, the postoperative vision is stable, and the operation is reversible. It does not change the biomechanics of the cornea, but also retains the accommodation. Middle-aged and elderly patients with presbyopia are a great boon.

Contents of the invention

A posterior chamber type phakic progressive multifocal intraocular lens, comprising an optical zone, a supporting part at the edge of the optical zone, and supporting haptics, the angle between the plane where the supporting haptics are located and the plane where the main body of the intraocular lens is located is between 10-20 degrees , the intraocular lens optical zone has both the far vision zone and the near vision zone, and the diopter will smoothly transition from the far vision zone to the near vision zone in a step-by-step manner. The front and rear surfaces of the intraocular lens optic zone are generally one One surface is spherical or aspheric, and the other surface is a progressive free-form surface;

The aspherical surface type characterization equation is:

Among them, c is the reciprocal of the radius of curvature of the basic spherical surface of the aspheric surface, x is the vertical distance from any point on the curve to the abscissa axis Z, A _2i is the coefficient of the high-order term of the aspheric surface, and m and n are not less than 1 Integer and n>m, k is the cone coefficient;

The diopter of the aspheric surface is obtained by the following formula:

_P1 is the diopter of the aspheric surface of the intraocular lens, n _L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, and r is the basic radius of curvature of the front surface of the intraocular lens, where

The progressive free-form surface characterization equation is:

Wherein, c _x , _cy are respectively the radius of curvature of the basic spherical surface in the x and y directions of the progressive free-form surface, and k _x and _ky are the conic coefficients in the x and y directions respectively;

The diopter of the progressive free-form surface is obtained by the following formula:

P ₂ is the diopter of the progressive free-form surface of the intraocular lens, n _L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, r ₁ and r ₂ are the maximum and minimum curvature radii of the progressive free-form surface of the intraocular lens, respectively, where,

The astigmatism of the progressive free-form surface is obtained by the following formula:

C is the astigmatism of the progressive free-form surface of the intraocular lens, n _L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, r ₁ and r ₂ are the maximum and minimum curvature radii of the progressive free-form surface of the intraocular lens, respectively, where,

Optionally, it is made of soft transparent hydrophilic or hydrophobic acrylic material, the refractive index n _L is in the range of 1.4-1.6, and the dispersion coefficient is 40-55.

Optionally, the optical zone and the support haptics are integrally formed using the same material.

Optionally, the diameter of the effective optical zone of the optical zone is 5.0 mm to 6.0 mm; the thickness of the first support haptic and the second support haptic are both 0.05 mm to 0.2 mm.

Optionally, several small circular holes are opened at 2 mm to 6 mm outside the optical zone. The diameter of the small holes is between 0.2 mm and 0.6 mm. The existence of the small holes is conducive to the circulation of aqueous humor and effectively reduces the occurrence of glaucoma. .

Optionally, the optical zone can provide a diopter of -10.0D to +10.0D, and the variation range of the progressive optical power is +0.5D to +5.0D.

Optionally, the optical zone may provide 3D cylinder power.

A method for preparing a posterior chamber type phakic progressive multifocal intraocular lens, characterized in that the method includes but is not limited to:

First, determine the patient's individual eye use needs, determine the distance point and near point position of the intraocular lens, and determine the parameters such as the distance diopter, near vision diopter, and near-use addition.

Second, according to the distance diopter and the near diopter, determine the curvature radius of the far point and the near point, and design the meridional addition curve of the progressive multifocal intraocular lens according to the curvature radius parameters.

Thirdly, the obtained meridional addition curve is converted into other curves, and the converted curve is evenly distributed on the entire progressive multifocal intraocular lens to determine the distribution of diopter and cylinder power of the progressive multifocal intraocular lens.

Fourth, calculate the surface sagittal height distribution of the asymptotic surface through the addition curve.

Fifth, program through MATLAB to obtain the sphericity and cylindricality of the asymptotic surface.

Sixth, the single-point diamond ultra-precision machining technology is used to process the progressive free-form surface structure derived by MATLAB on the front and rear surfaces of the substrate.

Seventh, preliminary inspection. First, use an aspheric profiler to detect whether the lens surface conforms to the design value. If it matches, go to the next step of inspection. If it does not match, return to the sixth step and reprocess until it meets the requirements in the seventh step.

Eighth, optical inspection, using the automatic measurement of the lens meter, measure the diopter of all points on the progressive surface, whether it is consistent with the design value, if it matches, complete the processing, if not, return to the sixth step and reprocess until the eighth step is satisfied requirements.

The beneficial technical effects of the present invention are:

The optical body of the present invention has a progressive free-form surface, and the diopter of the intraocular lens increases gradually from top to bottom, so that the eyes can see objects at long distances, medium distances, and short distances from different areas, and produce asymmetric and personalized imaging effects .

The present invention is an implantable progressive multifocal intraocular lens, which combines the design concepts of phakic intraocular lens and progressive multifocal spectacle lens, and is used for intraocular implantation of middle-aged and elderly patients with both myopia and presbyopia. Realize the clearness of far, medium and near vision, and at the same time realize the real removal of the mirror.

Instructions attached

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings that are required in the description of the embodiments or the prior art.

Fig. 1 is a schematic diagram for illustrating a simulated implantation position of a posterior chamber type phakic progressive multifocal intraocular lens;

Fig. 2 is a schematic front view of a posterior chamber type phakic progressive multifocal intraocular lens;

Figure 3 is a schematic side view of the posterior chamber type phakic progressive multifocal intraocular lens;

Figure 4 is a regional distribution map of the posterior chamber type phakic progressive multifocal intraocular lens;

Figure 5 is a diagram of the meridian addition curve for the design of the progressive multifocal intraocular lens of the posterior chamber type phakic eye;

Fig. 6 is a kind of ellipse adding light curve figure;

Figure 7 is a contour map of the sphere of the progressive multifocal intraocular lens of the posterior chamber type phakic eye;

Fig. 8 is a contour map of the cylindricality of the progressive multifocal intraocular lens of the posterior chamber type phakic eye.

Explanation of reference signs

101-cornea; 102-iris; 103-posterior chamber phakic progressive multifocal intraocular lens; 104-natural lens; 105-ciliary sulcus; 201-support haptics; ; 204-loop hole; 205-positioning groove; 206-central hole; 207-round hole; 401-far vision area; 402-near vision area;

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a simulated implantation position of a posterior chamber type phakic progressive multifocal intraocular lens (hereinafter referred to as intraocular lens), wherein the intraocular lens can be implanted between the iris 102 and the natural lens 104 .

Figure 2 is the front view of the posterior chamber type phakic progressive multifocal intraocular lens, and Figure 3 is a schematic side view of the posterior chamber type phakic progressive multifocal intraocular lens; as shown in Figure 2 and Figure 3, the intraocular lens includes an optical zone 203 , the supporting portion 202 and the supporting haptics 201 at the edge of the optical zone.

Among them, the optical zone 203 has a refractive function, and can provide a diopter of -10D to +10D, and the range of progressive refractive power is +0.5D to +5.0D; the front and rear surfaces of the optical zone 203 are generally a spherical surface Or an aspherical surface, while the other surface is a progressive free-form surface; the center of the optical zone 203 has a central hole 206, and the diameter of the central hole 206 is between 0.2 mm and 0.6 mm. The existence of the central hole 206 is conducive to the circulation of aqueous humor, effectively Reduce the occurrence of glaucoma.

The support portion 202 on the edge of the optical zone is located at the periphery of the optical zone 203 and is designed in a plate shape. The support portion 202 on the edge of the optical zone has two round holes 207 on the upper and lower sides. The diameter of the round holes 207 is between 0.2 mm and 0.6 mm. Circulation of aqueous humor; there is a rectangular positioning groove 205 on the upper and lower sides of the supporting part 202 on the edge of the optical zone. The size of the positioning groove 205 is 0.2mm*0.5mm, which is used to determine the rotation position of the intraocular lens during eye implantation.

The support haptics 201 are located at the four corners of the support portion 202 at the edge of the optical zone, and two of the support haptics 201 have haptic holes 204 with a diameter of 0.2mm-0.6mm for the circulation of aqueous humor.

FIG. 4 is a regional distribution map of the posterior chamber type phakic progressive multifocal intraocular lens. As shown in FIG.

Among them, the distance vision area 401 can provide diopters of -10D to +10D. This area can provide a clear distance vision function for the human eye in a relaxed state of viewing; the near vision area 402 can provide diopters of +0.5D to +5.0D. , this area can provide clear near vision function for the human eye in the state of myopia and downsight. The distance vision zone 401 to the near vision zone 402 realizes a continuous vision range; the peripheral astigmatism zone 403 can provide 3D cylinder power to meet the requirements of astigmatism.

The artificial lens designed in the present invention is made of soft transparent hydrophilic or hydrophobic acrylic material, the refractive index n _L ranges from 1.4 to 1.6, and the dispersion coefficient is 40 to 55.

The preparation method of the progressive multifocal intraocular lens:

The artificial lens material designed by the present invention is hydrophilic polymethacrylate, the refractive index of the material is 1.46, and the Abbe number is 45; the refractive index of aqueous humor is 1.336; the design wavelength λ is 0.546um; the diameter of the optical zone is 6.0mm; The surface diopter is -5D.

First, determine the patient's personalized eye needs. Through testing, the patient needs -0.24D for distance use, +1.74D for near use, and +1.98D for near use. Since the refractive power of the posterior surface of the intraocular lens is -5D, Then the diopter of the progressive surface is 4.76D～6.74D; the distance between the far point of view and the center of the intraocular lens is 1mm, and the addition length is 3mm;

Second, according to the determined diopter range, the far point of vision is 19.5mm, and the near point of vision is 13.8mm; program through MATLAB, draw the addition curve, and select a curve for far vision and near vision through comparison It is relatively stable, and the change of the curve is relatively smooth (as shown in Figure 5).

Third, convert the obtained meridional addition curve into an elliptic curve (as shown in Figure 6), the formula of the elliptic curve is:

Among them, a is the semi-major axis of the ellipse; b is the semi-minor axis of the ellipse; c is the half focal length of the ellipse.

When the y coordinate value is closer to 0, the semi-major axis a of the ellipse is closer to the half focal length c, and the ellipse addition curve at this time is the line segment between the far point and the near point, that is, the distribution of this elliptic curve can be determined Diopter and cylinder power distribution of progressive multifocal intraocular lens.

Fifth, according to the calculated sagittal height distribution equation of the progressive surface of the intraocular lens, program through MATLAB, select points with an interval of 0.1 mm to calculate the sphericity and cylindrical power of the progressive surface, and draw the graph, as shown in Figure 7. High line map, Fig. 8 is the contour map of cylinder degree.

Results Analysis and Discussion:

It can be seen from Figure 7 that the diopter of the far zone of the intraocular lens is +4.82D, the diopter of the near zone is +6.75D, and the addition of light between the distance reference point and the near reference point is +1.93D. It can be seen that the diopter of the progressive surface satisfies Design requirements +4.76D ~ +6.74D. Combining with Figure 8, it can be seen that the maximum cylindricality of the progressive surface of the intraocular lens is less than 0.25D, and the cylindricality is less than 2D in the stable area of the far vision area and the near vision area, and the areas with larger cylindricality are mainly concentrated in areas where people are less The edge areas on both sides used have no significant impact on human eye imaging, which is consistent with the original design requirements.

Claims

A posterior chamber type phakic progressive multifocal intraocular lens, comprising an optical zone, a supporting part at the edge of the optical zone, and supporting haptics, the angle between the plane where the supporting haptics are located and the plane where the main body of the intraocular lens is located is between 10-20 degrees , the intraocular lens optical zone has both the far vision zone and the near vision zone, and the diopter will smoothly transition from the far vision zone to the near vision zone in a step-by-step manner. The front and rear surfaces of the intraocular lens optic zone are generally one One surface is spherical or aspheric, and the other surface is a progressive free-form surface;

The aspherical surface type characterization equation is:

Among them, c is the reciprocal of the radius of curvature of the basic spherical surface of the aspheric surface, x is the vertical distance from any point on the curve to the abscissa axis Z, A 2i is the coefficient of the high-order term of the aspheric surface, and m and n are not less than 1 Integer and n>m, k is the cone coefficient;

The diopter of the aspheric surface is obtained by the following formula:

P1 is the diopter of the aspheric surface of the intraocular lens, n L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, and r is the basic radius of curvature of the front surface of the intraocular lens, where

The progressive free-form surface characterization equation is:

Wherein, c x , cy are respectively the radius of curvature of the basic spherical surface in the x and y directions of the progressive free-form surface, and k x and ky are the conic coefficients in the x and y directions respectively;

The diopter of the progressive free-form surface is obtained by the following formula:

P 2 is the diopter of the progressive free-form surface of the intraocular lens, n L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, r 1 and r 2 are the maximum and minimum curvature radii of the progressive free-form surface of the intraocular lens, respectively, where,

The astigmatism of the progressive free-form surface is obtained by the following formula:

C is the astigmatism of the progressive free-form surface of the intraocular lens, n L is the refractive index of the intraocular lens, n is the refractive index of the aqueous humor in the human eye, r 1 and r 2 are the maximum and minimum curvature radii of the progressive free-form surface of the intraocular lens, respectively, where,
The progressive multifocal intraocular lens according to claim 1 is characterized in that it is made of soft transparent hydrophilic or hydrophobic acrylic material, the refractive index n L is in the range of 1.4-1.6, and the dispersion coefficient is 40-55.
The progressive multifocal intraocular lens according to claim 1, characterized in that, the optical zone and the haptics are made of the same material and integrally formed.
The progressive multifocal intraocular lens according to claim 1, wherein the diameter of the effective optical zone of the optical zone is 5.0 mm to 6.0 mm; the thickness of the first haptic and the second haptic are both 0.05 mm to 0.2 mm. mm.
The progressive multifocal intraocular lens according to claim 1, characterized in that several small circular holes are opened at 2 mm to 6 mm outside the optical zone, and the diameter of the small holes is between 0.2 mm and 0.6 mm. It is beneficial to the circulation of aqueous humor and effectively reduces the occurrence of glaucoma.
The progressive multifocal intraocular lens according to claim 1, wherein the optical zone can provide a diopter of -10.0D to +10.0D, and the range of progressive diopter is +0.5D to +5.0D.
The progressive addition intraocular lens according to claim 1, wherein the optical zone can provide 3D cylinder power.