CN212234798U

CN212234798U - Astigmatic correcting intraocular lens

Info

Publication number: CN212234798U
Application number: CN202022091508.0U
Authority: CN
Inventors: 贾晓林; 卢奕; 王海林; 刘庆淮; 王晓宽; 曹德强; 孙洋; 谭恩鹏
Original assignee: Shanghai Kangende Medical Technology Co ltd
Current assignee: Shenyang Kangende Medical Science and Technology Co Ltd
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2020-12-29
Anticipated expiration: 2030-09-22

Abstract

The utility model discloses an astigmatism correcting artificial lens. The astigmatism-corrected intraocular lens includes an optical portion having formed on an outer surface thereof a first mark representing a principal meridian of maximum power, the first mark being for alignment with a corneal meridian in which a midline of a surgical incision is located. Because the influence of the surgical incision on the corneal meridian where the surgical incision is located is diopter reduction, the first mark on the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located in the surgery, so that the main meridian of the maximum diopter of the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located, the diopters of the main meridian and the corneal meridian can be offset positively and negatively, and the correction can be performed on the surgery-induced astigmatism. Moreover, when the artificial lens is implanted, the first mark is only required to be aligned with the midline of the incision, the positioning is easy, the operation difficulty is lower, and the applicability is wider.

Description

Astigmatic correcting intraocular lens

Technical Field

The utility model relates to the field of medical equipment, in particular to an astigmatism correcting intraocular lens.

Background

Cataract surgery has evolved from the past reconstructive surgery to the present day refractive cataract surgery age. People pay more attention to how to look better while pursuing the look. The method not only enables cataract doctors to try to improve the corrected vision of patients, but also aims to improve the naked eye vision of the patients and improve the postoperative visual quality of the patients. Astigmatism is one of the major factors that cause deterioration of naked eye vision.

Astigmatism is a refractive abnormal manifestation of the eye, related to the curvature of the cornea. After parallel rays enter the eye, the eyeball cannot focus on one point (focus) due to different refractive powers of the eyeball on different meridian lines, and a clear object image cannot be formed, and the condition is called astigmatism. Astigmatic eyes do not form sharp images either by accommodation or by moving the distance between the target and the eye. Mild astigmatism tends to cause asthenopia, and high astigmatism seriously affects vision. Astigmatism of a human eye mainly consists of corneal astigmatism and crystalline lens astigmatism, and after cataract surgery, the crystalline lens is removed, and then the total astigmatism of the eye is mainly caused by the corneal astigmatism. Thus, the ability to correct for corneal astigmatism can affect the quality of vision of the patient after cataract surgery.

An intraocular lens is a special lens made of an artificial synthetic material. The shape function of the artificial lens is similar to that of the crystalline lens of a human eye, the turbid crystalline lens is removed after cataract surgery, the artificial lens is implanted into the eye to replace the original crystalline lens, so that external objects are focused and imaged on the retina, and surrounding scenes can be seen clearly. Thus, intraocular lens implantation is an essential step in cataract surgery. Intraocular lenses can be classified into astigmatic intraocular lenses (Toric IOLs) and non-astigmatic intraocular lenses according to whether they have an astigmatic correcting function or not. In cataract surgery, the patient can form a sharp image on the retina by implanting an astigmatism correcting lens of a particular toric design.

The cornea completely free of astigmatism accounted for about 5% in the cataract population. Corneal astigmatism of 0.50D or less does not significantly affect the patient's vision and may also be referred to as physiological astigmatism. The common consensus of experts in clinical application of astigmatic correcting intraocular lenses in China (2017) provides the use indications of astigmatic crystals as follows: the regular corneal astigmatism is more than or equal to 0.75D, and cataract patients with the intention of distant vision aphakia can be considered for use. This proportion accounts for approximately 50% of the cataractous population.

By expression, astigmatism can be divided into regular astigmatism and irregular astigmatism, the former can be corrected by an astigmatism-correcting intraocular lens, and the latter cannot be corrected by an intraocular lens. The principal meridian of maximum refractive power and the principal meridian of minimum refractive power perpendicular to each other is the regular astigmatism, and the axial axis of the principal meridian of maximum refractive power can be classified into the normal astigmatism (90 ° ± 30 °), the reverse astigmatism (180 ° ± 30 °), and the oblique astigmatism (30 ° ± 60 ° or 120 ° -150 °). The refractive powers of the meridians are different, and irregular astigmatism is caused when the refractive powers of different parts of the same meridian are different. Corneal astigmatism is prevalent in cataractous people. In the cataractous population, the proportion of retrotactic light is about 58%, the proportion of cistronic light is about 25%, and the proportion of oblique light is about 17%. The retrodirective astigmatism has a more significant effect on vision than the paradirective astigmatism.

Surgical Induced Astigmatism (SIA) refers to astigmatism imparted to the cornea of a patient by the surgery itself, and is seen in many ophthalmic procedures. For example, cataract surgery, glaucoma surgery, ocular trauma surgery, etc., all of which may form a surgical incision in the cornea. The surgical incision can loosen the cornea at the position, so that the refractive power of the meridian where the incision is located is reduced, and the refractive power of the meridian in the vertical direction is increased. Thus, an incision over the cornea (at or near 90 °) will increase the power of the cornea in the vertical direction (at or near 180 °). Because the surgical incision for cataract surgery is made in whole or in part on the cornea, it can cause surgically-induced astigmatism to the patient's cornea. In China, most cataract surgeons are used to the superior incision. The surgically-induced astigmatism introduced by the superior incision results in a reduction in preoperative (even to retrograde) prescribed astigmatism and an increase in retrograde astigmatism. The temporal incision (horizontal) has the opposite effect.

The location, size and morphology of the surgical incision can all affect the magnitude of the surgically-induced astigmatism. Currently, in the ultrasonic emulsification technology widely used in clinic, two incisions of a main incision and a side incision are generally required to be made. The side incision is about 1mm in size generally, and surgical astigmatism caused by the side incision can be ignored in the previous research. Thus, surgically-induced astigmatism originates primarily from the main incision. The size of the main incision is typically 1.8mm to 3.2mm in phacoemulsification surgery. The results of previous studies showed that 1.8mm incisions produced a final SIA of approximately 0.29D, 2.2mm incisions produced a SIA of 0.31D to 0.40D, and 2.6 and 3.0mm incisions were 0.50 and 0.60 to 0.70D, respectively. In addition, conditions are limited in some domestic areas, a small incision surgical mode is still adopted, the incision size is generally 5.5-6mm, and the surgical astigmatism caused by the surgical mode can reach 2.00D.

Astigmatism has a vectorial nature with both magnitude and direction. The size and direction of astigmatism after cataract surgery are determined by the vector sum of the cornea astigmatism and the surgery-induced astigmatism before the surgery of the patient. The nature of surgically-induced astigmatism dictates that it increases as well as decreases the astigmatism due to the different locations of the incisions. However, if the surgeon adjusts the incision position to the different astigmatism meridians of different patients in order to reduce astigmatism, the surgeon has to adjust the surgical pose around the patient's head. However, making incisions in unaccustomed locations is not desirable because it often results in unpredictability of surgically-induced astigmatism, and can increase the difficulty of the surgery, extend the time of the surgery, and even increase the probability of surgical complications. Most doctors in China are used to adopt a cornea main incision with the upper part of 3.0-3.2mm, which brings out surgical astigmatism larger than 0.6D, and further increases astigmatism of patients with contra-normal astigmatism (accounting for about 60%), patients with preoperative cis-normal astigmatism degree smaller than or equal to 0.5D face the risk of converting the astigmatism into the contra-normal astigmatism, and the change from the cis-normal to the contra-normal brings obvious discomfort to the patients. Therefore, reducing the negative effects and uncertainty of surgically induced astigmatism in all cataract patients is a clinically significant problem.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an astigmatism correction type intraocular lens to correct the operation source type astigmatism of a patient caused by an operation.

The utility model provides an astigmatism correction type intraocular lens, include:

the optical part is provided with a first mark representing a main meridian of maximum power on the outer surface, and the first mark is used for being aligned with a corneal meridian where a midline of a surgical incision is located.

In some embodiments, the first indicium is formed at the edge of the optic.

In some embodiments, the optic includes an active optical zone and a rim portion, wherein the first mark is located in the active optical zone; alternatively, the first mark extends from the active optical zone to the edge portion; alternatively, the first mark is located at the edge portion.

In some embodiments, the optic has two first markings formed thereon that are symmetrical about the center of the optic.

In some embodiments, the first marker is disposed along the principal meridian of maximum power.

In some embodiments, the first marker comprises a marker line segment disposed on the meridian of maximum power; and/or the first mark comprises a plurality of mark points which are arranged on the main meridian of the maximum power at intervals.

In some embodiments, the first mark is formed by cutting an outer surface of the optic.

In some embodiments, the optic is also formed with an incision reference mark on at least one side of the first mark, the incision reference mark being configured to be parallel or aligned with an edge line of the surgical incision.

In some embodiments, the optic is formed with two incision reference marks on either side of a first mark, the first mark being centered on the two incision reference marks, the two incision reference marks being configured to be parallel or aligned with the respective side edge lines of the surgical incision.

In some embodiments, the distance between two incision reference marks ranges from [1.5mm, 5.5mm ].

In some embodiments, two cut reference marks are disposed in parallel.

In some embodiments, the astigmatic power of the astigmatic-corrected intraocular lens corresponds to the distance between the two incision reference marks.

In some embodiments, the optic further has formed thereon a second mark representing a principal meridian of least power, the second mark for alignment with the corneal meridian on which the astigmatism vector of the pre-operative corneal astigmatism and the surgically-induced astigmatism resulting from the surgical incision lie.

In some embodiments, the outer surface of the optic is spherical or aspherical.

In some embodiments, the intraocular lens further comprises haptics attached to the edge of the optic.

In some embodiments, the intraocular lens is used in intraocular lens implantation in a phakic eye.

In some embodiments, the intraocular lens is used for cataract surgery.

Based on the technical scheme that the astigmatism correction type intraocular lens includes optical part, is formed with the first mark that shows the main meridian of maximum power on the optical part, and first mark is used for the cornea meridian alignment with the incision's of performing the operation central line place. Because the influence of the surgical incision on the meridian where the surgical incision is reduced in diopter, the first mark on the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located in the surgery, so that the main meridian of the maximum diopter of the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located, the diopters of the main meridian and the corneal meridian can be offset positively and negatively, and the correction can be performed on the surgery-induced astigmatism. To the less patient of astigmatism degree before the art, implant the utility model discloses an intraocular lens avoids patient's postoperative astigmatism degree to increase, moreover the utility model discloses an intraocular lens only need when implanting with first mark and operation incision central line aim at can, the location is easy, the operation degree of difficulty is lower, the suitability is more extensive. Even to the great patient of astigmatic power before the art, if the patient wants to keep the astigmatic power before the art, adopt so the utility model discloses an intraocular lens implants and makes the operation process simple, and need not to carry out the precision measurement to cornea astigmatism before the art, also need not to carry out vector calculation, consequently is easier in clinical popularization.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the invention, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without undue limitation to the invention. In the drawings:

fig. 1 is a schematic view of an astigmatic intraocular lens according to an embodiment of the present invention;

fig. 2 is a schematic structural view of an optical portion of an astigmatic intraocular lens according to another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Unless specifically stated otherwise, the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously positioned and the spatially relative descriptors used herein interpreted accordingly.

Currently, the main correction methods for regular corneal astigmatism are excimer laser corneal ablation, limbal relaxing incisions and implantation of astigmatism-correcting intraocular lenses. The astigmatism correction range of the excimer laser corneal ablation is limited, astigmatism degree retroversion is easy to occur after operation, the correction effect is unstable, and the patient needs to bear extra high operation cost. The limbal loosening incision has the advantage of being performed simultaneously during cataract surgery, without the need for additional surgical trauma or surgical expense. But the correction range is small, the effect is unstable, and the predictability is poor. In addition, scars formed on the cornea by the limbal loosening incision can increase the high-order aberration of the cornea, easily generate a plurality of vision interference phenomena and influence the postoperative vision quality. Implanting an astigmatic intraocular lens has many advantages over the above correction methods. The artificial lens corrects corneal astigmatism and can be simultaneously completed in cataract operation. Meanwhile, the artificial lens has a large correction range and various cylinder power selections, and meets the requirements of people with different degrees of astigmatism. The artificial lens has high correction precision and stronger predictability, and the retroversion of astigmatism is not easy to occur after operation. Many clinical experiences already exist on the artificial lens, and a plurality of clinical studies prove that the artificial lens has good rotational stability after operation and reliable correction effect. Therefore, the clinical practice generally adopts the implantation of an astigmatism-correcting intraocular lens to correct the corneal astigmatism.

The astigmatism of the astigmatism-corrected intraocular lens is actually converted from the lens plane to the power of the corneal plane, and the postoperative residual astigmatism is calculated based on the power. The two are roughly converted into the following relation: the number of crystal planes x 0.68 is the number of corneal planes, and the magnitude of the multiplied factor is determined by the distance between the two planes, i.e., the anterior chamber depth. For example, a crystal with an astigmatism of 1D will actually have a corrective effect of 0.68D at the corneal plane. The equivalent sphere power of the astigmatic crystal is the average value of the maximum refractive power meridian diopter and the minimum refractive power meridian diopter of the crystal. The commercially available crystals typically have an equivalent spherical power of between-10D and + 40D.

The astigmatism correcting artificial lens has good correcting effect and is inseparable from a plurality of factors. The method comprises the following steps: accurate measurement of corneal astigmatism before operation, accurate marking and implantation during operation, stable operation-induced astigmatism of an operator, effective position of an artificial lens and good rotational stability of the artificial lens after operation. Therefore, the requirement of measuring equipment is high, the operation process is relatively complex, the influence factors are more, the price is relatively high, and the higher expectation value of the patient on the operation result also brings difficulty to the clinical practical use and popularization of the astigmatic crystal. Thus, most cataract surgeries not only do not correct the patient's corneal astigmatism, but also introduce surgically-induced astigmatism to the patient.

The use indication of the astigmatic lens proposed by experts in clinical application of astigmatic correction intraocular lenses in China (2017) is that the regular corneal astigmatism is more than or equal to 0.75D and can be considered by cataract patients with far vision aphakia willingness. This indication has the disadvantage of ignoring those patients who have less than 0.75D of astigmatism before surgery but have an overall astigmatism of greater than 0.75D due to increased surgically induced astigmatism after surgery, or who have preoperatively prescribed astigmatism and become retrooperatively astigmatic. This group of patients was excluded from the accommodative population of astigmatic lenses, but patients with preoperative astigmatism of less than 0.75D accounted for approximately 50% of the cataractous population. Patients in this group will have to suffer from poorer visual quality after surgery than before cataract development, or have inconvenience to live relying on previously unnecessary glasses.

The utility model discloses astigmatism correction formula intraocular lens corrects operation source nature astigmatism. As shown in fig. 1, the astigmatic intraocular lens according to an embodiment of the present invention includes an optical portion 4 and haptics 5 attached to the rim of the optical portion 4. The haptics 5 have a supporting function for the optical portion 4. The haptics 5 are long plate-like structures and may be L-shaped, C-shaped, or the like. The optic 4 and haptics 5 may be made of the same material or may be made of different materials. In this embodiment, the optic 4 and haptics 5 are made of the same material, such as an acrylate. Specifically, the acrylate may be a hydrophilic acrylate or a hydrophobic acrylate. The acrylate allows the lens to better adhere to the capsular bag and helps to reduce the likelihood of rotation of the lens after implantation.

As shown in fig. 1, the optical portion 4 has first marks 1 formed on the outer surface thereof for indicating the principal meridian of maximum power, the first marks 1 being intended to be aligned with the corneal meridian in which the midline of the surgical incision is located.

Because the influence of the surgical incision on the meridian where the surgical incision is reduced in diopter, the first mark 1 on the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located in the surgery, so that the main meridian of the maximum diopter of the intraocular lens is aligned with the corneal meridian where the midline of the surgical incision is located, the diopters of the main meridian and the corneal meridian can be offset positively and negatively, and the correction can be performed on the surgery-induced astigmatism. To the less patient of astigmatism power before the art, implant the intraocular lens of this embodiment and avoid patient astigmatism power after the art to increase, and the intraocular lens of this embodiment only need when implanting with first mark 1 and operation incision central line align can moreover, the location is easy, the operation degree of difficulty is lower, the suitability is more extensive. Even for a patient with large preoperative astigmatism, if the patient wants to keep the preoperative astigmatism, the intraocular lens of the embodiment is adopted for implantation, so that the operation process is simple, the precise measurement of the preoperative corneal astigmatism is not needed, and the vector calculation is also not needed, so that the intraocular lens is easy to popularize in clinic.

In order to make the artificial lens of the present embodiment also be used for correcting the preoperative astigmatism, the outer surface of the optical portion 4 of the artificial lens of the present embodiment is further formed with a second mark 2 representing the principal meridian of minimal power, and the second mark 2 is used for aligning the astigmatism vectors of the preoperative corneal astigmatism and the surgically-induced astigmatism with the corneal meridian in which the astigmatism vectors lie. When the preoperative astigmatism needs to be corrected, an operator can implant the preoperative astigmatism and the surgical astigmatism according to the original implantation alignment mode under the condition of calculating the vector sum of the preoperative astigmatism and the surgical astigmatism. Therefore, the application range of the artificial lens of the embodiment is wider.

In the present embodiment, the first mark 1 is disposed along the principal meridian of maximum power. The second markers 2 are located along the principal meridian of minimal power.

Specifically, as shown in fig. 1, in the present embodiment, the first marker 1 is a marker line segment provided on the power principal meridian. The second markers 2 are a plurality of marker points disposed on the minimum power principal meridian. Of course, the first mark 1 may be in the form of a mark point, and the second mark 2 may be in the form of a mark line segment, and the form of which the mark is expressed is not limited as long as the maximum power principal meridian and the minimum power principal meridian can be expressed.

In order to improve the positioning accuracy of the intraocular lens of the present embodiment, as shown in fig. 2, in another embodiment, the optical portion 4 is further formed on its outer surface with an incision reference mark 3 on at least one side of the first mark 1, the incision reference mark 3 being used to be parallel to or aligned with an edge line of the surgical incision.

The incision reference marker 3 of this embodiment is used to aid in referencing the alignment of the first marker 1 with the midline of the surgical incision. The incision reference mark 3 is aligned with the edge line of the surgical incision, so that when the intraocular lens is positioned in the surgery, the incision reference mark 3 is aligned with the edge line of the surgical incision, and then the first mark 1 can be quickly aligned with the midline of the surgical incision by using a reference object such as a scalpel. The incision reference mark 3 may also be arranged parallel to the edge line of the surgical incision, in which case the incision reference mark 3 may be located inside the edge line of the surgical incision or outside the edge line of the surgical incision, and when positioning the intraocular lens during surgery, the incision reference mark 3 is parallel to the edge line of the surgical incision so that the first mark 1 is aligned with the center of gravity of the surgical incision.

Preferably, the optical portion 4 of the present embodiment is formed with two incision reference marks 3 respectively located at both sides of the first mark 1, the first mark 1 is located at the center of the two incision reference marks 3, and the two incision reference marks 3 are used for respectively aligning with the edge lines at both sides of the surgical incision. The alignment of the two incision reference marks 3 with the two lateral edges of the surgical incision during surgery naturally results in the alignment of the centrally located first mark 1 with the midline of the surgical incision, so that the placement of the incision reference marks 3 can be used to assist in the accurate positioning of the intraocular lens.

In other embodiments, the two incision reference marks 3 are parallel to the two edge lines of the surgical incision, respectively.

The distance between the two incision reference marks 3 of this embodiment ranges from [1.5mm, 5.5mm ]. The distance between the two incision reference marks 3 may be the same as the width of the surgical incision or may be different. In a specific operation, since the width of the surgical incision is different due to the size of the scalpel and the habit of the surgeon, setting the distance between the two incision reference marks 3 to the above range in the present embodiment makes the intraocular lens of the present embodiment suitable for different applications.

Each mark of the present embodiment is located at the edge of the optic 4. And the length of each mark is not more than 1mm, so that the arrangement of the marks is prevented from influencing the function of the artificial lens.

The edge of the optical portion 4 refers to the position of the optical portion 4 near the circumferential edge line. In some embodiments, the optic 4 includes an active optic zone. Each of the marks is located at the edge of the effective optical zone. In other embodiments, the optical portion 4 includes an effective optical area and a rim portion located radially outside the effective optical area, and in this case, each mark may be provided only on the rim of the effective optical area or may extend from the effective optical area to the rim portion. Of course, in other embodiments, the above-mentioned marks may be provided only on the edge portion.

Specifically, as shown in fig. 2, the first mark 1 of the present embodiment is located at the edge of the optical portion 4. And the first mark 1 is a mark line segment extending on the meridian of maximum power.

In other embodiments not shown in the figures, the first marker may also be a plurality of marker points spaced apart on the principal meridian of maximum power. Of course, the marks may be in many forms, such as dots, circles, long lines, spaced lines, parallel lines, or combinations thereof.

The optical portion 4 of the present embodiment is formed with two first marks 1 that are symmetrical with respect to the center of the optical portion 4. The intraocular lenses of the present embodiment can be easily aligned and implanted during the intraoperative lens positioning process, and are suitable for the needs of different surgeons.

In the present embodiment, the two first markers 1 may be both in the form of marker line segments or both in the form of marker points as shown in fig. 2. Of course, one of the first marks 1 may be a mark line segment, and the other first mark 1 may be a mark point.

Likewise, the second marker 2 and the incision reference marker 3 may take the form of a marker line segment or a marker point. The mark points may be in the form of solid points as shown in fig. 2, or may be in the form of hollow points as shown in fig. 1.

The first markings 1 of the present embodiment are formed by cutting in the intraocular lens. For example by precision knife cutting or by laser etching. In other embodiments the first indicia may be printed, affixed, etc. to the intraocular lens. Other marks may be formed by cutting, printing, adhering, or the like

Since the size of the surgical astigmatism caused by the surgical incision is positively correlated with the size of the incision, the astigmatic power of the implanted intraocular lens is correlated with the size of the surgical astigmatism, and the size of the incision is correlated with the distance between the two incision reference marks 3, the astigmatic power of the astigmatism-corrected intraocular lens of the present embodiment corresponds to the distance between the two incision reference marks 3.

Specifically, the crystal plane power × coefficient is the corneal plane power, where the magnitude of the coefficient is determined by the distance between the two planes, i.e., the anterior chamber depth. For example, a crystal with an astigmatism of 1D has an actual corrective effect of 0.68D at the corneal plane. The equivalent sphere power of the astigmatic crystal is the average of the diopter of the maximum refractive power meridian and the diopter of the minimum refractive power meridian of the crystal.

The range of astigmatism of the lens of this example ranged from 0.25D to 3.5D, progressing at intervals of 0.12D to 0.5D. For example, an intraocular lens with 1.00D of astigmatism can correct about 0.7D of corneal planar astigmatism. The lens has an equivalent sphere power of 21.5D and a distance between the incision reference lines of 3.0 mm. The intraocular lens is suitable for implantation by a surgeon having a surgical incision of 3.0mm and surgically induced astigmatism of about 0.7D into an eye for a patient with an equivalent sphere power requirement of 21.5D.

For another example, an intraocular lens with a 0.75D lens astigmatism can correct about 0.5D corneal plane astigmatism. The lens has an equivalent sphere power of-6.00D and a distance between the incision reference lines of 3.0 mm. The intraocular lens is suitable for implantation by a surgeon having a surgical incision of 3.0mm and surgically induced astigmatism of about 0.5D into an eye for a patient having an equivalent sphere power requirement of-6.00D.

For another example, an intraocular lens with 2.5D astigmatism has about 1.75D corneal plane astigmatism to correct. The lens has an equivalent sphere power of +15.00D and a distance between the incision reference lines of 5.5 mm. The intraocular lens is then suitable for implantation by a surgeon having a surgical incision of 5.5mm and surgically induced astigmatism of about 1.75D into an eye for a patient with an equivalent sphere power requirement of + 15.00D.

The outer surface of the intraocular lens of this embodiment is spherical or aspherical.

The intraocular lens of this embodiment may be a multifocal lens or an EDOF lens.

The intraocular lens of the present embodiment may be used in intraocular lens implantation in a phakic eye.

In particular, the intraocular lens is used in cataract surgery. It can also be used in other ophthalmic surgery where an incision is made in the cornea. The structure of an intraocular lens according to an embodiment of the present invention will be described in detail with reference to fig. 1 and 2.

As shown in fig. 1, the astigmatism-corrected intraocular lens includes an optical portion 4 and haptics 5 attached to the periphery of the optical portion 4. Wherein the optic 4 is circular and the haptics 5 are C-shaped. In the present embodiment, two first marks 1 symmetrical about the centers thereof and two second marks 2 symmetrical about the centers thereof are formed on the edge of the outer surface of the optical portion 4.

As shown in fig. 2, the optical portion 4 includes a first mark 1, a second mark 2, and a cut reference mark 3 formed on the edge of the outer surface thereof.

Wherein the first mark 1 is disposed along a principal meridian of maximum power, the second mark 2 is disposed along a principal meridian of minimum power, and the first mark 1 and the second mark 2 are perpendicular to each other. Two cutout reference marks 3 are symmetrically disposed on both sides of the first mark 1, respectively.

The intraocular lens of the present embodiment includes two first marks 1 (up-down direction in fig. 1), two second marks 2 (left-right direction in fig. 1), and two pairs of incision reference marks 3 (up-down direction in fig. 1) symmetrically disposed with respect to the center thereof. The intraocular lens of this embodiment can therefore be accurately positioned regardless of the lens positioning.

When only correcting the operation-induced astigmatism, selecting the artificial lens with the equivalent sphere power and the astigmatism power which are correspondingly required according to the equivalent sphere power requirement of the patient and the size of the operation incision of the operator, and aligning the incision reference mark of the artificial lens with the edge lines on two sides of the operation incision respectively in the operation to accurately position the artificial lens and implant the artificial lens. Therefore, when only correcting the astigmatism caused by the incision, the astigmatism degree of the implanted crystal can be selected just by determining the operation-induced astigmatism of a doctor before the crystal is implanted, and the vector calculation is not required to be carried out in combination with the cornea astigmatism before operation. When the artificial lens is implanted, the first mark representing the main meridian of maximum power is directly aligned with the midline of the surgical incision, and the incision reference line on the lens and a scalpel making the main incision can assist in aligning the midline of the surgical incision, so that the cornea marking is not needed before or during surgery, and the surgical process is further simplified.

When correcting the preoperative astigmatism and the surgery-induced astigmatism together, a doctor firstly uses an astigmatism crystal calculator to calculate the magnitude and the direction of the vector sum of the preoperative astigmatism and the surgery-induced astigmatism before a surgery, marks the direction of the vector sum on a cornea by using a marking pen, and then aligns a second mark representing a main meridian of minimum power on the crystal with the mark of the vector sum when implanting the crystal. Meanwhile, the making position of the incision is marked, and the incision is made according to the position in the operation. The intraocular lens of the present embodiment is therefore also suitable for use in existing implantation alignments.

In summary, the astigmatism correction intraocular lens of the present embodiment provides a better option for preoperative patients with low astigmatism, i.e. the astigmatism state before operation that does not need correction can be maintained, and only the influence of the operation-induced astigmatism on postoperative vision is corrected.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, it should be understood by those skilled in the art that: the invention can be modified or equivalent substituted for some technical features; without departing from the spirit of the present invention, it should be understood that the scope of the claims is intended to cover all such modifications and variations.

Claims

1. An astigmatic correcting intraocular lens comprising:

the optical system comprises an optical part (4), wherein a first mark (1) representing a main meridian of maximum power is formed on the outer surface of the optical part (4), and the first mark (1) is used for being aligned with a corneal meridian where a midline of a surgical incision is located.

2. Astigmatic intraocular lens according to claim 1, characterized in that the first mark (1) is formed at the edge of the optical portion (4).

3. The astigmatic intraocular lens according to claim 2, wherein the optical portion (4) comprises an effective optical zone and a rim portion, wherein the first mark (1) is located in the effective optical zone; alternatively, the first mark (1) extends from the effective optical zone to the edge portion; alternatively, the first mark (1) is located at the edge portion.

4. The astigmatic intraocular lens according to claim 1, characterized in that the optical portion (4) is formed with two of the first marks (1) that are symmetrical with respect to the center of the optical portion (4).

5. Astigmatic intraocular lens according to claim 1, characterized in that the first mark (1) is arranged along the principal meridian of maximum power.

6. The astigmatic intraocular lens according to claim 5, wherein the first mark (1) comprises a mark line segment provided on the meridian of maximum power; and/or the first mark comprises a plurality of mark points which are arranged on the main meridian with maximum power at intervals.

7. Astigmatic intraocular lens according to claim 1, characterized in that the first mark (1) is formed by cutting the outer surface of the optical portion (4).

8. Astigmatic corrected intraocular lens according to any one of claims 1 to 7, characterized in that the optical portion (4) is further formed with an incision reference mark (3) on at least one side of the first mark (1), the incision reference mark (3) being intended to be parallel or aligned with an edge line of a surgical incision.

9. Astigmatic corrected intraocular lens according to claim 8, characterized in that the optical portion (4) is formed with two incision reference marks (3) respectively located on both sides of the first mark (1), the first mark (1) being located in the center of the two incision reference marks (3), the two incision reference marks (3) being intended to be parallel or aligned with the edge lines on both sides of the surgical incision, respectively.

10. Astigmatic intraocular lens according to claim 9, characterized in that the distance between the two incision reference marks (3) ranges from [1.5mm, 5.5mm ].

11. Astigmatic intraocular lens according to claim 9, characterized in that the two incision reference marks (3) are arranged in parallel.

12. The astigmatic intraocular lens according to claim 9, characterized in that the astigmatic power of the astigmatic intraocular lens corresponds to the distance between the two incision reference marks (3).

13. Astigmatic corrected intraocular lens according to any one of claims 1 to 7, characterized in that the optical portion (4) is further formed with a second mark (2) representing the principal meridian of least power, the second mark (2) being intended to be aligned with the corneal meridian where the astigmatism vector of the preoperative corneal astigmatism and the surgically-induced astigmatism brought about by the surgical incision lie.

14. The astigmatic intraocular lens according to any one of claims 1 to 7, characterized in that the outer surface of the optical portion (4) is spherical or aspherical.

15. The astigmatic intraocular lens according to claim 1, characterized in that the intraocular lens further comprises haptics (5) attached to the edge of the optic (4).

16. An astigmatic intraocular lens according to claim 1, wherein the intraocular lens is used for intraocular lens implantation in a phakic eye.

17. The astigmatic intraocular lens of claim 16, wherein the intraocular lens is used for cataract surgery.