CN102397117B - Artificial lens, method for manufacturing the same and method for treating cataract using the same - Google Patents

Abstract

The present invention provides a method for manufacturing an intraocular lens in one aspect, comprising the steps of: measuring the curvature of the corneal anterior surface of the eye in a first analysis range, and measuring the curvature of the posterior surface of the cornea in a second analysis range, the first analysis range and the second analysis range The two analysis ranges have the same center point, the thickness of the cornea is measured at the center point, the corneal diopter is calculated by an equation, the eye axis is measured, and the effective lens position is calculated from the curvature of the posterior surface of the cornea. According to the corneal diopter, the eye Axes and effective lens positions are used to calculate the dioptric power of the intraocular lens, and the intraocular lens is manufactured at the dioptric power. Another aspect of the invention is an intraocular lens manufactured according to the method described above. Another aspect of the invention is a method of using an intraocular lens for the treatment of cataracts.

Description

Artificial intraocular lenses and manufacture method thereof and use artificial intraocular lenses treat cataractous method

Technical field

The present invention relates to a kind of artificial intraocular lenses and manufacture method thereof, relate to especially a kind of artificial intraocular lenses who manufactures according to the radian of anterior surface of cornea and posterior surface of cornea and manufacture method thereof.

Background technology

Before patient is carried out to cataract operation, doctor must first calculate artificial intraocular lenses's radian and the position of putting.Wherein, artificial intraocular lenses's radian is to be calculated by the radian of patient's eyes cornea.Traditional method is just calculated the radian of cornea by an estimative figure., rectify in the people look once accepting refractive surgery as laser, it is inaccurate that this estimative figure can become.

Summary of the invention

The technical problem to be solved in the present invention is, rectifys in the people who looks once accepting refractive surgery as laser, and the calculating of existing computational methods Corneal Curvature is inaccurate.

For solving the problems of the technologies described above, the present invention provides a kind of method of manufacture of intraocular crystal on the one hand, comprises the following steps:

In the first analyst coverage, measure the anterior surface of cornea curvature of eyes,

In the second analyst coverage, measure the pos-terior corneal surface curvature of eyes, this first analyst coverage and the second analyst coverage have same central point,

At described central point, measure the thickness of cornea,

By following equation, calculate corneal diopter:

$K=P1+P2-\frac{d}{n1}P1P2$

Wherein, K is corneal diopter, and P1 is anterior surface of cornea diopter,

p2 is posterior surface of cornea diopter,

the corneal thickness of d for using ultrasonic corneal pachymeter to measure, the dioptric coefficient that n0 is air, the dioptric coefficient that n1 is cornea, the dioptric coefficient that n2 is aqueous humor, r1 is anterior surface of cornea curvature, r2 is pos-terior corneal surface curvature,

Measure axis oculi,

From described pos-terior corneal surface curvature, calculate effective crystal positions,

According to described corneal diopter, axis oculi and effectively crystal positions calculate described artificial intraocular lenses's diopter, and

With described diopter, manufacture described artificial intraocular lenses.

In one embodiment of the invention, described the first analyst coverage is the circle of 3 millimeters of diameters.

In one embodiment of the invention, described the second analyst coverage is that overall diameter is 10 millimeters, and interior diameter is the annulus of 7 millimeters.

In one embodiment of the invention, the central point that described central point is pupil.

Another aspect of the present invention is a kind of artificial intraocular lenses who makes according to said method, and described artificial intraocular lenses's diopter is according to corneal diopter, and axis oculi and effectively crystal positions calculate, wherein:

The anterior surface of cornea curvature that corneal diopter basis is measured out in the first analyst coverage, the pos-terior corneal surface curvature of measuring out in the second analyst coverage, and the corneal thickness that uses ultrasonic corneal pachymeter to measure out, calculate by following equation:

$K=P1+P2-\frac{d}{n1}P1P2$

Wherein, K is corneal diopter, and P1 is anterior surface of cornea diopter,

p2 is posterior surface of cornea diopter,

the corneal thickness of d for using ultrasonic corneal pachymeter to measure, the dioptric coefficient that n0 is air, the dioptric coefficient that n1 is cornea, the dioptric coefficient that n2 is aqueous humor, r1 is anterior surface of cornea curvature, r2 is pos-terior corneal surface curvature, and

Effectively crystal positions calculates by described pos-terior corneal surface curvature.

Another aspect of the present invention be a kind of use artificial intraocular lenses to treat cataractous method, comprise the following steps:

In the first analyst coverage, measure the anterior surface of cornea curvature of eyes,

In the second analyst coverage, measure pos-terior corneal surface curvature, this first analyst coverage and the second analyst coverage have same central point,

At described central point, measure the thickness of cornea,

By following equation, calculate corneal diopter:

$K=P1+P2-\frac{d}{n1}P1P2$

Wherein, K is corneal diopter, and P1 is anterior surface of cornea diopter, p2 is posterior surface of cornea diopter,

the corneal thickness of d for using ultrasonic corneal pachymeter to measure, the dioptric coefficient that n0 is air, the dioptric coefficient that n1 is cornea, the dioptric coefficient that n2 is aqueous humor, r1 is anterior surface of cornea curvature, r2 is pos-terior corneal surface curvature,

Measure axis oculi,

From described pos-terior corneal surface curvature, calculate effective crystal positions,

According to described corneal diopter, axis oculi and effectively crystal positions calculate described artificial intraocular lenses's diopter,

With described diopter, manufacture described artificial intraocular lenses,

Extract the crystal of cataract patient, and

Described artificial intraocular lenses is implanted in to described effective crystal positions of patient's ophthalmic.

The invention has the beneficial effects as follows: no matter whether patient carries out refractive surgery in the past, as laser, rectified and look operation, can calculate exactly artificial intraocular lenses's radian and the position of putting, thereby lower, because of artificial intraocular lenses's diopter mistake, cause artificial intraocular lenses to implant the probability that occurs permanent hypermetropia after cataract patient.Contrast prior art, the present invention once carried out the cataract patient of cornea refractive surgery to those, more accurate in the calculating of corneal diopter and effective crystal positions.

Wherein, the curvature that utilization of the present invention is measured out by instrument and thickness, calculate respectively the diopter of anterior surface of cornea and posterior surface of cornea, and the required adjustment of making of the distance between two surfaces, thereby can calculate more accurately corneal diopter.The pos-terior corneal surface curvature that uses the cornea periphery scope of performing an analysis to measure also can estimate that refractive surgery rectifys and look preoperative corneal diopter as laser more accurately, to calculate more accurately effective crystal positions.

Accompanying drawing explanation

Remaining part and accompanying drawing with reference to this description can be done further to understand to performance of the present invention and advantage; In these accompanying drawings, the label of same assembly is identical.In some cases, sub-labelling be placed in certain label to after hyphen to represent one of them of many similar assemblies.When mentioning certain label but while not writing some existing sub-labellings exactly especially, just refer to all these similar assemblies.

Fig. 1 a is the simplification cross-sectional view of normal human subject eyes.

Fig. 1 b rectifys and to look perioperative simplification cross-sectional view carrying out laser for mankind's eyes.The variation of postoperative anterior surface of cornea is represented by dotted lines.

Fig. 2 is according to one embodiment of the invention, a kind of flow chart of method of manufacture of intraocular crystal.

Fig. 3 is according to one embodiment of the invention, a kind of flow chart that obtains the method for corneal diopter.

Fig. 4 a is the front view of anterior surface of cornea, shows the strong relation that looking the scope of operation impact of the first analyst coverage and laser.

Fig. 4 b is the front view of posterior surface of cornea, shows the strong relation that looking the scope of operation impact of the second analyst coverage and laser.

Fig. 5 a is for being used Orbscan point centered by corneal vertex to measure the view of cornea surface curvature.

Fig. 5 b is for being used Orbscan point centered by pupil center to measure the view of cornea surface curvature.

The specific embodiment

First, with reference to Fig. 1 a, this figure is the simplification cross-sectional view of mankind's eyes 20.Cornea 30 is the most external of eyes 20.In cornea 30 outsides, be air 28, and be aqueous humor 32 between cornea 30 and crystal 26.Light enters from outward, and the dioptric through cornea 30 and crystal 26, finally focuses on retina 31.

Referring now to Fig. 1 b, this figure has shown that eyes are carrying out for example strong front and back contrast of looking operation of Myopia laser of cornea refractive surgery.Cornea 30 has anterior surface of cornea 22 and posterior surface of cornea 24.Before carrying out refractive surgery, anterior surface of cornea 22 and posterior surface of cornea are approximately spherical.In the middle of anterior surface of cornea 22, part can be cut or be polished in operation, thereby becomes flat, new anterior surface of cornea 34 after formation operation.

Fig. 2 has shown the flow chart of a manufacture of intraocular crystal method.The method comprises acquisition corneal diopter (step 36), measure axis oculi (step 38) and calculate effective crystal positions (step 40), and according to above-mentioned diopter, axis oculi and effectively crystal positions calculate described artificial intraocular lenses's diopter (step 42), then manufacture described artificial intraocular lenses (step 44) with this diopter.

From the flow chart of Fig. 2, can learn, manufacture of intraocular crystal first will know corneal diopter, and in traditional cornea curvimeter, the diopter of the cornea calculating be

wherein r is the curvature of the anterior surface of cornea measuring out, and n is a single dioptric coefficient 1.3375 of fabricating according to the eye model of Gullstrand.The curvature that behind one of them of this numeral is assumed to be anterior surface of cornea 22 and posterior surface of cornea 24 becomes a fixing ratio (6.8: 7.7), so anterior surface of cornea and posterior surface of cornea are taken as single surface and calculate in this model.Rectify while looking operation carrying out Myopia laser because the curvature of anterior surface of cornea 34 reduces and cornea in the thickness attenuation of centre part, above-mentioned hypothesis is no longer set up, so uses above-mentioned imaginary numerical calculation corneal diopter out to there will be error.

Fig. 3 is for removing to obtain the flow chart of the method for corneal diopter (step 36) according to one embodiment of the invention.First the method is measured the anterior surface of cornea curvature of eyes and measures pos-terior corneal surface curvature (step 46) in the second analyst coverage in the first analyst coverage, and this first analyst coverage and the second analyst coverage have same central point.Then at described central point, measure the thickness (step 48) of cornea, i.e. distance between anterior surface of cornea and posterior surface of cornea.After obtaining these parameters, the method is calculated corneal diopter (step 50) by following equation:

$K=P1+P2-\frac{d}{n1}P1P2$ [equation (1)]

Wherein, K is corneal diopter, and P1 is anterior surface of cornea diopter, p2 is posterior surface of cornea diopter,

the corneal thickness of d for using ultrasonic corneal pachymeter to measure, n0 is the dioptric coefficient (1.0) of air, n1 is the dioptric coefficient (1.376) of cornea, n2 is the dioptric coefficient (1.336) of aqueous humor, r1 is anterior surface of cornea curvature (millimeter), and r2 is pos-terior corneal surface curvature (millimeter).

With said method, calculating corneal diopter compared with only coming more accurately by imaginary numerical calculation, is a fixing ratio because this method is not supposed anterior surface of cornea curvature and pos-terior corneal surface curvature mistakenly.Said method is used the curvature r1 that measures out, r2 and thickness d, first calculate respectively the diopter P1 of anterior surface of cornea and posterior surface of cornea, P2, and the required adjustment of making of the distance between two surfaces, corneal diopter just can calculate exactly from equation (1).

The selection of analyst coverage can produce great impact to the accuracy of said method.Because the curvature of measuring out in different analyst coverages has difference.In one embodiment of the invention, the first analyst coverage is the circle 52 of 3 millimeters of diameters as shown in Fig. 4 a.The reason of selecting 3 millimeters is that all anterior surface of cornea that carry out the strong patient depending on operation of laser all can become flat in this scope.If 3 millimeters of diameter serious offenses, while being particularly bigger than 5 millimeters, the edge of scope may depart from laser and rectify the scope (representing with broken circle 54) of looking operation impact.This can cause the curvature of scope center and peripheral different, and causes that error appears in the result finally drawing.In another embodiment, the diameter of the first analyst coverage is 5 millimeters or following.

Compared with anterior surface of cornea, measuring of pos-terior corneal surface curvature is more prone to error, and reason is that cornea curvimeter must be first just can measure the data of posterior surface of cornea through the refraction of anterior surface of cornea as Orbscan II.There is document to be recorded Orbscan II and once carry out the inaccuracy that laser is rectified the pos-terior corneal surface curvature look surgical patient measuring.Laser is rectified curvature and the thickness that can change the middle part of anterior surface of cornea depending on operation, thereby the pos-terior corneal surface curvature that order is measured is out higher than practical situation.

In one embodiment of the invention, the second analyst coverage is the circle of 10 millimeters of diameters.These the 10 millimeters sizes that are about whole cornea, and because the relation that the deviation of measuring mainly partly occurs in centre, therefore measuring whole cornea gained error is out low compared with the data of only using mid portion to draw.In another embodiment of the present invention, as Fig. 4 b shows, the periphery that the second analyst coverage is cornea.Surround circularly outward, the diameter of the cylindrical 58 of annulus 56 is the same 10 millimeters of the face of catching up with, and the diameter of inner circle 60 is 7 millimeters.At Myopia laser, rectify and to look in operation, because anterior surface of cornea is rectified in this scope Stimulated Light, to look the impact of operation less, thus the hypothesis of cornea front and rear surfaces curvature ratio still come into force, thereby improve the accuracy of calculating.Laser is rectified scope depending on the operation impact about 5-6 millimeter in the middle of being substantially, and the circle of 5 millimeters of diameters represents with broken circle 54.Substantially only using the peripheral data that draw is accurately compared with using whole cornea.Some cornea curvimeters can free selection analysis scope as Orbscan II, therefore can only use peripheral measuring.If other cornea curvimeters can not be accomplished this point, need to use whole cornea scope to error is reduced to minimum.

The calculating of tradition corneal curvature is all with optical center, or point centered by the summit 62 of cornea.Fig. 5 a is for being used Orbscan point centered by corneal vertex to remove to measure the view of one of them surface power of cornea., light must first could arrive retina through pupil, and the center of pupil might not be overlapping with the summit of cornea.If use the central point that the summit of cornea is analyst coverage, the curvature of measuring out may not be best suited for patient's.As shown at Fig. 5 a, white point represents the circle that ，Er Bai Quanweiyi pupil center of pupil center is the center of circle.White circle has departed from concentric black circle, the circle that the corneal vertex of take is the center of circle as seen from the figure.Therefore the curvature of, measuring out from Hei Quan is not optimal to patient.

In one embodiment of the invention, as shown in Figure 5 b, the central point of first and the second analyst coverage is made as the central point of pupil.Because all, measure all centered by pupil, so do not need to comprehend, that pupil do not depart from that corneal vertex causes is wrong and revise again, and the result drawing is best suited for patient's.It is the function of analyst coverage central point that some cornea curvimeters are selected pupil as Orbscan II has.

As mentioned above, calculate artificial intraocular lenses's diopter, except obtaining corneal diopter, also to measure axis oculi and calculate effective crystal positions.Axis oculi can be measured such as A-mode ultrasonic ripple scanning etc. by known method.Effectively the calculating of crystal positions can be calculated by double-K method.Two K are here respectively and do refractive surgery and rectify and to look preoperative corneal diopter and postoperative corneal diopter as laser.If without any the data of corneal diopter, just need to estimate that this diopter is to make to calculate purposes before operation.

In one embodiment of the invention, preoperative corneal diopter is estimated from postoperative posterior surface of cornea diopter.The method is first used above-mentioned method to take periphery and is removed to measure the diopter of posterior surface of cornea as analyst coverage.Because known posterior surface of cornea the place ahead is that cornea tissue rear is aqueous humor, and know their dioptric coefficient, the diopter of posterior surface of cornea just can be used

calculate, n1 wherein, the definition of n2 and r2 is with above the same.Value is multiplied by a constant again and just can learns the diopter of anterior surface of cornea thus, then substitution equation (1) just can draw preoperative corneal diopter.Because the peripheral Stimulated Light of posterior surface of cornea is rectified, to look the impact of operation minimum, the corneal diopter more than the calculating cornea diopter of can estimating more accurately to perform the operation.

Postoperative corneal diopter can obtain according to the method described in Fig. 3 or other method.After learning these two numerical value, effectively crystal positions can calculate by double-K method.

Obtaining corneal diopter, after axis oculi and effectively crystal positions, artificial intraocular lenses's diopter can be used known method to calculate, and for example Holladay 1, and Holladay 2, Haigis, SRK/T, Hoffer Q method etc.

Another aspect of the present invention is a kind of artificial intraocular lenses, and artificial intraocular lenses's diopter is according to corneal diopter, and axis oculi and effectively crystal positions calculate.The anterior surface of cornea curvature of corneal diopter from measuring out in the first analyst coverage, the pos-terior corneal surface curvature of measuring out in the second analyst coverage, with the corneal thickness that uses ultrasonic corneal pachymeter to measure out, by above-mentioned equation (1), calculate corneal diopter.Effectively crystal positions calculates by described pos-terior corneal surface curvature.

In a preferred embodiment, described corneal diopter obtains by the method shown in Fig. 2 and Fig. 3.

Another aspect of the present invention is that a kind of use artificial intraocular lenses is to treat cataractous method.The method first obtains corneal diopter, measure axis oculi and calculate effective crystal positions, and according to above-mentioned diopter, axis oculi and effectively crystal positions calculates described artificial intraocular lenses's diopter, then manufacture described artificial intraocular lenses with this diopter.The method that obtains described corneal diopter is first in the first analyst coverage, measure the anterior surface of cornea curvature of eyes and measure pos-terior corneal surface curvature in the second analyst coverage, and this first analyst coverage and the second analyst coverage have same center.Then at described center, measure the thickness of cornea, i.e. distance between anterior surface of cornea and posterior surface of cornea.After obtaining these parameters, the method is calculated corneal diopter by above-mentioned equation (1).Effectively crystal positions calculates by described pos-terior corneal surface curvature.

After having manufactured artificial intraocular lenses, the method also comprises the crystal of extracing cataract patient, then described artificial intraocular lenses is implanted in to described effective crystal positions.

Above content is in conjunction with concrete embodiment further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.

Claims (7)

1. A method for manufacturing artificial lens, is characterized in that, comprises the following steps: The curvature of the anterior surface of the cornea of the eye is measured in the first analytical range, measuring the curvature of the posterior surface of the cornea of the eye in a second analysis range, the first analysis range and the second analysis range having the same center point, Measure the thickness of the cornea at the central point, Corneal diopters are calculated by the following equation: $\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}$ Among them, K is the diopter of the cornea, and P1 is the diopter of the anterior surface of the cornea, namely

P2 is the refractive power of the posterior surface of the cornea, that is d is corneal thickness measured by ultrasonic pachymeter, n0 is the refractive index of air, n1 is the refractive index of cornea, n2 is the refractive index of aqueous humor, r1 is the curvature of corneal anterior surface, and r2 is the posterior surface of cornea curvature, measure eye axis, Calculate the effective lens position from the corneal posterior surface curvature, calculating the diopter of said intraocular lens based on said corneal diopter, eye axis and effective lens position, and The intraocular lens is manufactured in the diopter of the intraocular lens. 2. The method of claim 1, wherein the first analysis range is a circle with a diameter of 3 mm. 3. The method of claim 1, wherein the second analysis range is a circle with a diameter of 10 mm. 4. The method of claim 1, wherein the second analysis range is a circular ring with an outer diameter of 10 mm and an inner diameter of 7 mm. 5. The method of claim 1, wherein the center point is the center point of the pupil. 6. An intraocular lens manufactured by the method according to any one of claims 1-5, the diopter of the intraocular lens is calculated according to the corneal diopter, eye axis and effective lens position, wherein: Corneal refraction is calculated from the curvature of the anterior surface of the cornea measured in the first analysis range, the curvature of the posterior surface of the cornea measured in the second analysis range, and the corneal thickness measured using an ultrasonic pachymeter, by the following equation: $\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}$ Among them, K is the diopter of the cornea, and P1 is the diopter of the anterior surface of the cornea, namely

P2 is the refractive power of the posterior surface of the cornea, that is

d is corneal thickness measured by ultrasonic pachymeter, n0 is the refractive index of air, n1 is the refractive index of cornea, n2 is the refractive index of aqueous humor, r1 is the curvature of corneal anterior surface, and r2 is the posterior surface of cornea curvature, and Effective lens positions were calculated from the curvature of the posterior corneal surface. 7. A method for calculating the diopter of an intraocular lens, comprising the following steps: The curvature of the anterior surface of the cornea of the eye is measured in the first analytical range, measuring the curvature of the posterior surface of the cornea of the eye in a second analysis range, the first analysis range and the second analysis range having the same center point, Measure the thickness of the cornea at the central point, Corneal diopters are calculated by the following equation: $\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; 2</span>}$ Among them, K is the diopter of the cornea, and P1 is the diopter of the anterior surface of the cornea, namely

P2 is the refractive power of the posterior surface of the cornea, that is d is corneal thickness measured by ultrasonic pachymeter, n0 is the refractive index of air, n1 is the refractive index of cornea, n2 is the refractive index of aqueous humor, r1 is the curvature of corneal anterior surface, and r2 is the posterior surface of cornea curvature, measure eye axis, calculating the effective lens position from the corneal posterior surface curvature, and The diopter of the intraocular lens is calculated based on the corneal diopter, eye axis and effective lens position.

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