1. Field of the Invention
The present disclosure relates to an accommodative intraocular lens to be inserted into a lens capsule from which contents were removed by cutting an anterior capsule of a lens capsule during cataract surgery, etc.
2. Description of the Related Art
The following description of related art sets forth the inventors' knowledge of related art and certain problems therein and should not be construed as an admission of knowledge in the prior art.
Normally, human eye focusing is performed by changing a thickness of a crystalline lens. As shown in
Concrete focusing mechanism will be explained as follows. For example, in the case of seeing a far distance, as shown in
On the other hand, in the case of trying to see a near object, as shown in
As explained above, in accordance with contraction and relaxation of the ciliary muscle, the ciliary body protrudes or retracts in the radial direction of the lens capsule by a predetermined amount (concretely about 0.3 mm), causing movements of the equator of the lens capsule in the radial direction by the same degree. This causes a change in the thickness of the crystalline lens (concretely by about 0.3 to 0.5 mm). Thus, focusing is performed by deflecting the light entered into an eye. It is known that contraction and relaxation of the ciliary muscle of the ciliary body are kept well even at an old age in the same manner as at a young age. On the other hand, it is also known that contents and a lens capsule of a crystalline lens become hardened to lose the flexibility, resulting in less changes in the thickness of the crystalline lens, which loses the force of voluntary adjusting the focal point (hereinafter referred to as “focusing ability) when seeing a near distance from the state when seeing a far distance (which will be called presbyopia).
By the way, among diseases relating to crystalline lenses, there is a disease called “cataract” in which a crystalline lens becomes cloudy mainly caused by advancing age. Many patients have cataract surgery for treating their cataracts. In the cataract surgery, normally, a method is employed in which a circular hole is formed in the anterior capsule, and the cloudy crystalline lens is removed through the circular hole by an ultrasonic crystalline lens emulsion suction method to remain only a transparent lens capsule in an opened state, and an artificial lens called “intraocular lens” is inserted into the lens capsule. The cataract surgery of this method has been currently applied to patients of more than 1 million in Japan every year and patients of more than 3 million in the United States of America every year.
An intraocular lens generally used for a cataract surgery is provided with an optical section having a refractive power capable of focusing on one of a far distance, an intermediate distance, and a near distance after the surgery depending on the request of the patient, and is called “single focus intraocular lens.” This single focal point intraocular lens is fixed to the equator of the lens capsule or therearound by the tensile forces of the lens supporting sections extending from the peripheral portion of the optical section in the radially outward direction. However, since the lens is not designed to change the thickness of the optical section (lens) or move the optical section back and forth like a human eyes crystalline lens and therefore has no focusing ability, it was necessary to compensate the focusing ability by using a pair of eyeglasses having a power corresponding to the distance to an object to be seen.
Further, there is a so-called multifocal intraocular lens in which concentric sections different in refractive power are formed in the lens optical section (this is called “multiple refraction type multifocal intraocular lens”) or a structure causing an optical diffraction phenomenon (this is called multiple diffraction type multifocal intraocular lens) is formed in the lens optical section so that light to be entered into an eye is taken in a dispersed manner for a far distance use and a near distance use (in some cases, further for an intermediate distance use). However, in such multifocal intraocular lens, there are reports that patients report a halo phenomenon (an object looks with light rings), a glare (an object looks glistening), insufficient eyesight, or insufficient contrast sensitivity. Thus, such multifocal intraocular lenses could not have sufficiently satisfied patient's requests.
Under the circumstances, there have been conventionally proposed some intraocular lens (accommodative intraocular lens) in which an optical section moves back and forth to perform focusing in accordance with the lens capsule movements accompanied by contract and relaxation of the ciliary muscle of the ciliary body like a human crystalline lens (see the below listed Patent Documents 1 to 3).
The intraocular lens disclosed by Patent Document 1 is generally called “synchrony lens IOL” which is a silicon accommodative intraocular lens in which a convex lens is arranged forward and a concave lens is arranged rearward, both the lenses being connected by spring-like connecting portions.
Further, the accommodative intraocular lens disclosed by Patent Document 2 is generally called “1CU-IOL” which is an acrylic accommodative intraocular lens including one lens and four sheets of movable plate-shaped supporting portion.
Further, the accommodative intraocular lens disclosed by Patent Document 3 is general called “crystal lens” which is an accommodative intraocular lens made of acryl and polyimide and including one lens, two sheets of plate members arranged at both peripheral portions of the lens, and a loop-shaped leg formed at the tip end of each plate member.
[Patent Document] Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. JP-2005-533611
[Patent Document 2] Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. JP-2004-538086
[Patent Document 3] Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2007-512907
However, it is generally said that a focusing ability required for an accommodative intraocular lens to see from a far distance to a near distance with no problem without glasses is required to be 2.0D or more. A human eye has about 2.0D of focusing ability (pseudoaccommodation) by a focusing ability other than the deformation of a lens considered due to a multifocal property, a spherical aberration of a cornea, and a pupillary movement. Adding 2.0D of the pseudoaccommodation and 2.0D of adjustment ability due to the function of the accommodative intraocular lens results in 4.0D, which exerts sufficient adjusting ability. For example, in the case of an accommodative intraocular lens having a normal lens which is +2.0D in refractive power, a focusing ability of 2.0D or more is exerted when the lens is moved by 0.75 mm in the fore-and-aft direction. Therefore, in order to exert a focusing ability of 2.0D or more, it is required to move the lens by at least 1.5 mm or more.
Considering the above, a conventional accommodative intraocular lens is configured to move the optical section in the fore-and-aft direction utilizing deformation of the lens capsule in accordance with contraction and relaxation by the ciliary muscle of the ciliary body. However, since movement amounts of the ciliary body in the radial direction are small, movement amounts of the equator of the lens capsule are also small (about 0.3 mm). This results in very small movements of the optical section in the fore-and-aft direction. Thus, it is considered to be difficult to exert a focusing ability of 2.0D or more.
Concretely, in Patent Document 1, the equator of the lens capsule moves by about 0.3 mm centripetally, resulting in a forward movement of the equator of the lens capsule by about 0.3 mm centripetally by the focal adjustment. However, even if a lens having a very large refractive power (for example, the refractive power of the lens is +32D) is used as a forward lens and a concave lens having a level of the optical power adjusted to an eye of a patient is used as a rearward lens, only a focusing ability of 0.88D is obtained theoretically. The focusing ability has not reached 2.0D, which cannot exert sufficient focusing ability. Further, the accommodative intraocular lens is an integral member including two sheets of lens and connecting portions connecting the lenses, and therefore the entire volume is rather large. This requires a large incision to insert the accommodative intraocular lens. Thus, it is hard to say that such lens is not preferable as an accommodative intraocular lens.
Further, in Patent Document 2, when the equator of the lens capsule is centripetally moved by about 0.3 mm, it is considered that the lens moves by about 0.6 mm forward. The focusing ability also has not reached 2.0D, which cannot exert sufficient focusing ability. Further, in this accommodative intraocular lens, it is considered that after cataract surgery, etc., the growth of lens epithelial cells occurred near the equator of the lens capsule results in adhesion of the anterior capsule and the posterior capsule and the capsular fibrosis thereof, causing sclerosis of the lens capsule and that the equator of the lens capsule is pressed in the direction of the Zinn's zonule fiber by the tensile force of the lens supporting section in the radially outward direction; as a result, the continuous tonus of the Zinn's zonule fiber has been deteriorated or lost. Therefore, in actual, there is a possibility that the lens does not move forward.
Further, in Patent Document 3, it is configured to move the lens forward at the time of focusing on the assumption that adhesion and capsular fibrosis of the lens capsule occur to a certain degree. However, as to the accommodative intraocular lens, there is no report that the ciliary body protrudes rearward. Further, even if the ciliary body protrudes rearward, it is considered such that when the side of the equator of the lens capsule formed by Zinn's fibers moves rearward, the lens moves rearward. Further, since movement amounts of the ciliary body are small, it is considered that the lens hardly moves. Therefore, it is at least hard to say that sufficient focusing ability is exerted.
As explained above, most of conventional accommodative intraocular lens could not exert sufficient focusing ability. In fact, as for the aforementioned conventional accommodative intraocular lens, many clinical test results have been reported. However, no objective reports demonstrating sufficient movements of the optical section in the fore-and-aft direction, and rather many reports demonstrating no or slight movements of the lens in the fore-and-aft direction have been made. Further, it also is pointed out that focusing effects of the conventional accommodative intraocular lens largely rely on monovision (one of eyes is adjusted to slight near sight and the other of eyes is adjusted to slight stronger near sight to enable seeing from a far object to a near object with both eyes) and/or pseudoaccommodations such as multifocal properties or spherical aberrations of a cornea, or contraction of a pupil.
The description herein of advantages and disadvantages of various features, embodiments, methods, and apparatus disclosed in other publications is in no way intended to limit the present invention. For example, certain features of the preferred described embodiments of the invention may be capable of overcoming certain disadvantages and/or providing certain advantages, such as, e.g., disadvantages and/or advantages discussed herein, while retaining some or all of the features, embodiments, methods, and apparatus disclosed therein.
The preferred disclosed embodiments of the present invention have been developed in view of the above-mentioned and/or other problems in the related art. The preferred disclosed embodiments of the present invention can significantly improve upon existing methods and/or apparatuses.
The embodiments of the present invention was made in view of the aforementioned problems and aims to provide an accommodative intraocular lens capable of sufficiently exerting focusing ability.
In order to attain the aforementioned objects, some embodiments of the present invention provide an accommodative intraocular lens to be inserted into a lens capsule from which contents were removed. The accommodative intraocular lens includes an optical section made of a lens, and a plurality of lens supporting sections formed on a peripheral portion of the optical section. The lens supporting section includes one end portion connected to the peripheral portion of the optical section in a movable manner, and the other end portion to be engaged with an equator of the lens capsule or a lens capsule extension device. The one end portion and the other end portion are positioned on opposite sides with respect to a center of the optical section. The one end portion extends to branch on both sides of the optical section so as to respectively extend along a periphery of the optical section and then are connected with each other to thereby be formed into a loop shape in a manner as to surround the periphery of the optical section as a whole. In accordance with movements of the lens capsule or the lens capsule extension device caused by focusing of an eye, the other end portions of the lens supporting section move in an approaching/departing direction, moving each of one end portions of the lens supporting section in the fore-and-aft direction, which causes movements of the optical section in the fore-and-aft direction in accordance with the movements of the one end portions.
With this, the distance between one end portion and the other end portion of the lens supporting section becomes long, which enables effective conversion of movements of the other end portions of the lens supporting sections in the approaching/departing direction into movements of one end portion of the lens supporting sections in the fore-and-aft direction. For this reason, when the other end portions of the lens supporting sections slightly move in the approaching/departing direction in accordance with the slight movements of the lens capsule or the lens capsule extension device, each one end portion of the lens supporting section moves at the peripheral portion of the optical section, which in turn largely moves each one end portion of the lens supporting section in the fore-and-aft direction. In accordance with the movements, the optical section can be largely moved in the optical axis direction, enabling sufficient exertion of the focusing ability of the accommodative intraocular lens.
Further, the movements of the other end portions of the lens supporting sections in the approaching/departing direction can be assuredly converted into movements of the one end portions in the fore-and-aft direction, which in turn can stably move the optical section in the optical axis direction. At the same time, no symptom such as a glare occurs since there is no obstacle blocking or diffuse light in an optical path passing through the optical section from the pupillary area to the retina.
Further, in one embodiment, it is preferable that in the accommodative intraocular lens, the one end portion of the lens supporting section is connected to the peripheral portion of the optical section via a connecting portion in a movable manner. With this, it is possible to simply and assuredly move the one end portion of the lens supporting section by the peripheral portion of the optical section. The one end portion of the lens supporting section or the connecting portion can be provided with a slit extending in a circumferential direction of the optical section. Further, the connecting portion can be provided with one or a plurality of engaging grooves extending in the circumferential direction of the optical section on a rear surface or a front surface of the connecting portion so that one end portion of the lens supporting section is engaged with the engaging groove in a movable manner. The connecting portion also can be provided with one or more engaging hole extending in a circumferential direction of the optical section on a side surface of the connecting portion so that one end portion of the lens supporting section is engaged with the engaging hole in a movable manner.
Further, in one embodiment, it is preferable that the lens supporting section includes an urging member for urging an anterior capsule and a posterior capsule of the lens capsule in a manner as to distance the anterior capsule and the posterior capsule in the fore-and-aft direction, the urging member being provided at the other end portion of the lens supporting section. With this structure, the peripheral portion of the equator Se of the lens capsule S is expanded in the fore-and-aft direction to expand the equator Se of the lens capsule S and the equator Se of the lens capsule S is moved centripetally to reduce the diameter of the equator Se of the lens capsule S. This causes continuous tonus of the Zinn's zonule fibers Z. For this reason, the contraction/relaxation of the ciliary muscle is conveyed to the lens capsule via the Zinn′ zonule fibers, sufficient focusing ability can be exerted with high dimensional accuracy. Further, the crystalline lens equator expands to cause continuous flow of the hydatoid into the crystalline lens equator. This controls the growth or fibrillization of the lens epithelial cell, which makes it possible to control occurrence of after-cataract. Further, the other end portion of the lens supporting section is stably arranged at the vicinity of the equator Se of the lens capsule, which makes it possible to assuredly convey the movements of the lens capsule near the equator to the lens supporting section.
Further, in one embodiment, it is preferable that the urging member is formed into one or a plurality of curved shapes. With this structure, it is possible to urge the anterior capsule and the posterior capsule of the lens capsule in a manner as to distance in the fore-and-aft direction with a simple structure.
Further, in one embodiment, it is preferable that the urging member is formed into one or a plurality of loop shapes. With this structure, it is possible to more assuredly urge the anterior capsule and the posterior capsule of the lens capsule in a manner as to distance in the fore-and-aft direction.
Further, in one embodiment, it can be configured such that the urging member includes an anterior capsule supporting portion supporting the anterior capsule from an inside of the anterior capsule, a posterior capsule supporting portion supporting the posterior capsule from an inside of the posterior capsule, and a connection supporting portion connecting the anterior capsule supporting portion and the posterior capsule supporting portion, and wherein the connection supporting portion urges the anterior capsule supporting portion and the posterior capsule supporting portion in a manner as to distance in the fore-and-aft direction. With this structure, it is possible to more assuredly urge the anterior capsule and the posterior capsule of the lens capsule in a manner as to distance in the fore-and-aft direction.
Further, in one embodiment, it is preferable that the urging member is provided at tis inner side with an engaging member with which the other end portion of the lens supporting section is engaged. With this structure, the other end portion of the lens supporting section is engaged with the engaging member positioned inward of the connecting portion, and therefore the other end portion of the lens supporting section can be stably arranged near the equator Se of the lens capsule. Further, since the engaging member is not always required to have an urging force unlike the connecting portion, the degree of design freedom of materials, etc., can be enhanced.
Further, in one embodiment, it is preferable that the engaging member is formed into a plate shape extending in the fore-and-aft direction, wherein one end portion of the engaging member is connected to the one end portion of the urging member and the other end portion of the engaging member is connected to the other end portion of the urging member, and wherein the engaging member is formed in a manner as to bend toward a direction of the equator of the lens capsule. With this structure, the other end portion of the lens supporting section is engaged with the bent portion of the plate-shaped engaging member, and therefore the other end portion of the lens supporting section can be more stably arranged near the equator of the lens capsule.
Further, in one embodiment, it is preferable that a plurality of urging members are arranged along the circumferential direction of the lens capsule, and adjacent urging members are connected in the circumferential direction by two wire members, which constitutes a lens capsule extension device as a whole. With this structure, since urging members are connected in a circumferential direction, each urging member can be stably arranged along the equator of the lens capsule. This enables more stable arrangement of the other end portion of the lens supporting section near the equator of the lens capsule S.
Further, according to another aspect of the present invention, an accommodative intraocular lens includes an optical section, and a plurality of lens supporting sections, each of the plurality of lens supporting sections being formed into a loop shape as seen in an optical direction of the optical section. Each of the plurality of lens supporting sections includes one end portion connected to a peripheral portion of the optical section and the other end portion, the one end portion and the other end portion of each of the plurality of lens supporting sections being positioned on opposite sides with respect to a center of the optical section. Each of the plurality of lens supporting sections extends around a periphery of the optical section so as not to overlap the optical section as seen in the optical axis direction.
According to some embodiments of the present invention, the distance between one end portion and the other end portion of the lens supporting section becomes long, which enables effective conversion of the movements of the other end portions of the lens supporting sections in the approaching/departing direction into the movements of each one end portion of the lens supporting sections in the fore-and-aft direction. For this reason, when the other end portions of the lens supporting sections slightly move in the approaching/departing direction in accordance with slight movements of the lens capsule or the lens capsule extension device, each one end portion of the lens supporting section largely moves in accordance with the movements at the peripheral portion of the optical section, which in turn largely moves each one end portion of the lens supporting section in the fore-and-aft direction. In accordance with the movements, the optical section can be largely moved in the optical axis direction, enabling sufficient exertion of the focusing ability of the accommodative intraocular lens.
The above and/or other aspects, features and/or advantages of various embodiments will be further appreciated in view of the following description in conjunction with the accompanying figures. Various embodiments can include and/or exclude different aspects, features and/or advantages where applicable. In addition, various embodiments can combine one or more aspect or feature of other embodiments where applicable. The descriptions of aspects, features and/or advantages of particular embodiments should not be construed as limiting other embodiments or the claims. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like numbers refer to like elements throughout. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items and may be abbreviated as “/”. It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. Unless indicated otherwise, these terms are only used to distinguish one element from another. For example, a first object could be termed a second object, and, similarly, a second object could be termed a first object without departing from the teachings of the disclosure. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being “connected” or “coupled” to or “on” another element, it can be directly connected or coupled to or on the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). However, the term “contact,” as used herein refers to direct contact (i.e., touching) unless the context indicates otherwise. Terms such as “same,” “planar,” or “coplanar,” as used herein when referring to orientation, layout, location, shapes, sizes, amounts, or other measures do not necessarily mean an exactly identical orientation, layout, location, shape, size, amount, or other measure, but are intended to encompass nearly identical orientation, layout, location, shapes, sizes, amounts, or other measures within acceptable variations that may occur, for example, due to manufacturing processes. The term “substantially” may be used herein to reflect this meaning. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present application, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The preferred disclosed embodiments of the present invention are shown by way of example, and not limitation, in the accompanying figures.
In the following paragraphs, some preferred embodiments of the invention will be described by way of example and not limitation. It should be understood based on this disclosure that various other modifications can be made by those in the art based on these illustrated embodiments.
Next, a first embodiment of an accommodative intraocular lens according to the present invention will be explained with reference to
[Structure of Accommodative Intraocular Lens]
The accommodative intraocular lens 100 according to this embodiment is designed to be inserted or implanted into a lens capsule S from which a crystalline lens was removed by cataract surgery, etc. As shown in
The arrow A shown in
The optical section 10, as shown in
The connecting portion 50 is a member connecting the optical section 10 and the lens supporting section 20 at the peripheral portion of the optical section 10. The connecting portions 50 are provided so as to protrude from both the right and left side peripheral portions of the optical section 10, and arranged at opposed positions with respect to the center O of the optical section 10.
The lens supporting sections 20, as shown in
Further, each lens supporting section 20 is formed into a loop shape approximately circular in plan view. One end portion 201 of the lens supporting section 20 is connected to the peripheral portion of the optical section 10 via the connecting portion 50 in a movable manner, and the other end portion 202 thereof is configured to be engaged with the equator Se of the lens capsule S or therearound.
Further, in each lens supporting section 20, one end portion 201 and the other end portion 202 are positioned at opposite sides with respect to the center O of the optical section 10. This will be explained concretely as follows. Focusing attention on the lens supporting section 20 having one end portion 201 at the right side in
Further, each lens supporting section 20 is formed in a manner as to extend at the radially outside of the optical section 10. This will be explained concretely as follows. Focusing attention on the lens supporting section 20 having one end portion 201 on the right side of
Further, each lens supporting section 20 is configured such that the lens supporting sections 20 do not come into contact with each other when the optical section 10 moves in the optical axis direction. Explaining concretely, as shown in
Further, in each lens supporting section 20, as shown in
Further, in each lens supporting section 20, at least one end portion 201 is made of an elastic member having a predetermined restoring force, so that the connection to the optical section 10 is in a movable state with the restoring force of the resilient member. This will be explained concretely as follows. As shown in
Further, as shown in
Thus, in the accommodative intraocular lens 100 structured as explained above, when an external force is applied to each of the other end portions 202 of each lens supporting section 20 in the radially inward direction, the other end portions 202 move in the approaching direction. This results in a forward movement of the optical section 10. On the other hand, when the external force applied to each of the other end portions 202 of the lens supporting section 20 in the radially inward direction of the optical section 10 is released, the other end portions 202 move in the departing direction by the action of the restoring forces of one end portions 201. This results in a rearward movement of the optical section 10 so that the optical section 10 returns to its original position.
Hereinafter, the mechanism of movements of the optical section 10 in the optical axis direction will be concretely explained with reference to
Initially, in this accommodative intraocular lens 100, as shown in
Then, in this accommodative intraocular lens 100, as shown in
Further, in this accommodative intraocular lens 100, as shown in
On the other hand, in the accommodative intraocular lens 100 in the state shown in
In the accommodative intraocular lens 100, as shown in
In the aforementioned accommodative intraocular lens 100, comparing to a conventionally known accommodative intraocular lens (for example, the accommodative intraocular lens shown in Patent Document 2, hereinafter referred to as “conventional accommodative intraocular lens”) 100′, it becomes possible to effectively convert movements of the other end portions 202 of the lens supporting section 20 in the approaching/departing direction into movements of the optical section 10 in the fore-and-aft direction.
Hereinafter, this will be explained by comparing the accommodative intraocular lens 100 and the conventional accommodative intraocular lens 100′. Both the accommodative intraocular lens 100 and the conventional accommodative intraocular lens 100′ are provided with the same optical section 10 and allotted by the same number to the corresponding structure, and both the intraocular lens are distinguished by allotting a dash (′) to the numerals of the conventional accommodative intraocular lens. Further, the comparison is made under the condition that the movement of the other end portion is the same movement amount d.
In the lens supporting section 20 of the accommodative intraocular lens 100, as shown in
Considering the above, in the conventional accommodative intraocular lens 100′, as shown in
In the conventional accommodative intraocular lens 100′, as shown in
In the conventional accommodative intraocular lens 100′, as shown in
As explained above, in the present accommodative intraocular lens 100, the distance from one end portion 201 to the other end portion 202 is longer than in the conventional accommodative intraocular lens 100′. Therefore, even in cases where the other end portion 202 moves by the same movement amount in the same manner as in the conventional accommodative intraocular lens 100′, the movements of the other end portions 202 of the lens supporting sections 20 in the approaching/departing direction can be effectively converted into movements of one end portions 201 of the lens supporting sections 20 in the fore-and-aft direction. As a result, the movements can be effectively converted into movements of the optical section 10 in the fore-and-aft direction.
For this reason, when the other end portions 202 of the lens supporting sections 20 slightly move in the approaching/departing direction in accordance with the slight centripetal and centrifugal (i.e., radially inward and radially outward) movements of the lens capsule S in the vicinity of the equator Se thereof, each one end portion 201 and/or connecting portion 50 of the lens supporting section elastically deforms. This moves one end portion 201 of the lens supporting section 20 at the peripheral portion of the optical section 10. As a result, each end portion 201 of the lens supporting section 20 largely moves in the fore-and-aft direction, resulting in large movements of the optical section 10, which makes it possible to sufficiently exert the focusing ability.
In the aforementioned accommodative intraocular lens 100, as shown in
As shown in
Further, the equator Se of the lens capsule S expands to allow the continuous flow of the hydatoid into the equator Se of the lens capsule S to wash away mediators, such as, e.g., cytokine created by the lens epithelial cell, by itself advancing the growth of the lens epithelial cell. This controls growth and/or fibrillization of the lens epithelial cell, which makes it possible to control occurrence of after-cataract. Further, the other end portion 202 of the lens supporting section 20 is stably arranged at the vicinity of the equator Se of the lens capsule S, which makes it possible to assuredly convey the movements of the lens capsule S near the equator Se to the lens supporting section 20.
[Arrangement and Function of Present Accommodative Intraocular Lens]
Next, the arrangement and function of the present accommodative intraocular lens 100 will be explained with reference to
In arranging the present accommodative intraocular lens 100, as shown in
Next, the function of the present accommodative intraocular lens 100 inserted or implanted in an eye will be explained. As shown in
On the other hand, as shown in
In this embodiment, the lens supporting section 20 having the structure as shown in
Further, as shown in
Further, although the lens supporting section 20 is formed into an approximately-circular loop shape, the lens supporting section 20 can be formed into other shapes. For example, as shown in
Further, although two lens supporting sections 22 are provided, as shown in
Further, although at least one end portion 201 of the lens supporting section 20 is made of an elastic member having a restoring force, the lens supporting section 20 is not required to have a restoring force as long as the one end portion 201 is connected to the peripheral portion of the optical section 10 in a movable manner, and the material is not limited to an elastic member.
Further, although one end portion 201 of the lens supporting section 20 is connected to the peripheral portion of the optical section 10 via the connecting portion 50, the one end portion 201 can be directly connected to the peripheral portion of the optical section 10.
Next, second to eight embodiments according to the accommodative intraocular lens of the present invention will be explained with reference to
In an accommodative intraocular lens 500 of this embodiment, as shown in
According to this urging member 31, it is possible to more assuredly urge the anterior capsule Sf and the posterior capsule Sb of the lens capsule S in a manner as to distance in the fore-and-aft direction. Further, it is possible to consecutively apply a stress to the Zinn's zonule fibers Z and make the hydatoid flow into the equator Se of the lens capsule S, and therefore occurrence of after-cataract can be prevented. Further, since the urging member 31 functions as a cushion member between the equator Se of the lens capsule S and the other end portion 202 of the lens supporting section 20, it is possible to reduce the force for reducing the stress of the Zinn's zonule fibers Z by radially outwardly expanding the equator Se of the lens capsule S.
Next, a third embodiment of an accommodative intraocular lens according to the present invention will be explained with reference to
In the intraocular lens 600 of this embodiment, the urging member 32 is provided with an anterior capsule supporting portion 321 configured to support the anterior capsule Sf from the inside thereof, a posterior capsule supporting portion 322 configured to support the posterior capsule Sb from the inside thereof, and a connection supporting portion 323 connecting the anterior capsule supporting portion 321 and the posterior capsule supporting portion 322 and having a bent portion 323a capable of being bent radially outward. The connection supporting portion 323 urges the anterior capsule supporting portion 321 and the posterior capsule supporting portion 322 in a manner as to distance in the fore-and-aft direction. Further, the other end portion 202 of the lens supporting section 20 is engaged with the bent portion 323a of the urging member 32.
According to this urging member 32, accompanying the opening movement of the anterior capsule Sf and the posterior capsule Sb in the fore-and-aft direction by the near adjustment, when the anterior capsule supporting portion 321 and the posterior capsule supporting portion 322 move in the departing direction and therefore the bending degree of the bent portion 323a of the connection supporting portion 323 in the direction of the equator Se (radially outward) decreases, the other end portions 202 of the lens supporting sections 20 move in the approaching direction. In accordance with the movement, the optical section 10 can be moved forward in the optical axis direction.
Next, a fourth embodiment according to the accommodative intraocular lens of the present invention will be explained with reference to
In the accommodative intraocular lens 700 of this embodiment, the urging member 33 is formed by a curved plate formed into a curved shape in a manner as to expand radially outward from the upper end to the lower end. Further, this urging member 33 is provided at tis inner side with an engaging member 331 with which the other end portion 202 of the lens supporting section 20 is engaged.
This engaging member 331 is formed into a plate shape extending in the fore-and-aft direction. One end portion of the engaging member 331 positioned at the forward side is connected to the forward side one end portion of the urging member 33, and the other end portion of the engaging member 331 positioned at the rearward side is connected to the other end portion of the urging member 33. The engaging member 331 includes a bent portion 331a bent in the direction of the equator S2 of the lens capsule S (radially outward).
According to this urging member 33, the other end portion 202 of the lens supporting section 20 is engaged with the engaging member 331 positioned inward of the urging member 33, and therefore the other end portion 202 of the lens supporting section 20 can be stably arranged near the equator Se of the lens capsule S. Further, the other end portion 202 of the lens supporting section 20 is engaged with the bent portion 331a of the plate-shaped engaging member 331, and therefore the other end portion 202 of the lens supporting section 20 can be more stably arranged near the equator Se of the lens capsule S.
Next, a fifth embodiment according to the accommodative intraocular lens of the present invention will be explained with reference to
In the accommodative intraocular lens 800 of this embodiment, a plurality of urging members 33 are arranged along the circumferential direction of the lens capsule S, and adjacent urging members 33 are connected in the circumferential direction by two wire members 40, which constitutes a lens capsule extension device as a whole.
According to this structure, since urging members 33 are connected in the circumferential direction by each wire member 40, each urging member 33 can be stably arranged along the equator Se of the lens capsule S. This enables more stable arrangement of the other end portion 202 of the lens supporting section 20 near the equator Se of the lens capsule S.
Next, a sixth embodiment according to the accommodative intraocular lens of the present invention will be explained with reference to
In the accommodative intraocular lens 900 of this embodiment, as shown in
The slit 52a is formed on the rear surface of the connecting portion 52. However, the slit can be formed on the front surface of the connecting portion 52 so that the one end portion 201 of the lens supporting section 20 can be bent rearward via the slit 52a when the optical section 10 moves forward. Further, such a slit can be formed in one end portion 201 of the lens supporting section 20 so that the one end portion 201 of the lens supporting section 20 can be bent via the slit when the optical section 10 moves forward.
Next, a seventh embodiment according to the accommodative intraocular lens of the present invention will be explained with reference to
In this accommodative intraocular lens 1000 according to this embodiment, the connecting portion 53 has, as shown in
Although the one end portion 201 of the lens supporting section 20 is engaged with the outer engaging groove 53a, it can be configured such that the one end portion is engaged with the inner engaging groove 53a.
Since the engaging groove 53a is formed so as to be detached from and engaged with one end portion 201 of the lens supporting section 20, when the position of the accommodative intraocular lens 1000 in the fore-and-aft direction is not appropriate during the surgery or when there is a slight error in the power of the optical section 10 predicted before the surgery, the position of the accommodative intraocular lens 1000 can be corrected by detaching the lens supporting section 20 from the optical section 10 and engaging the lens supporting section 20 again while shifting the position, or the optical section 10 can be detached from the lens supporting section 20 to replace the optical section 10 with a new optical section 10 having a correct power.
Although two engaging grooves 53a are formed, one or three or more engaging grooves can be formed.
Although the engaging groove 53a is formed on the rear surface of the connecting portion 53, the engaging groove can be formed on the front surface of the connecting portion 53.
Next, an eighth embodiment according to the accommodative intraocular lens of the present invention will be explained with reference to
In this accommodative intraocular lens 1100 according to this embodiment, the connecting portion 54 has, as shown in
Although the one end portion 201 of the lens supporting section 20 is engaged with the outer engaging hole 54a, it can be configured such that the one end portion is engaged with the inner engaging hole 54a.
Since the engaging hole 54a is formed so as to be detached from and engaged with one end portion 201 of the lens supporting section 20, when the position of the accommodative intraocular lens 1100 in the fore-and-aft direction is not appropriate during the surgery or when there is a slight error in the power of the optical section 10 predicted before the surgery, the position of the accommodative intraocular lens 1100 can be corrected by detaching the lens supporting section 20 from the optical section 10 and engaging the lens supporting section 20 again while shifting the position, or the optical section 10 can be detached from the lens supporting section 20 to replace the optical section 10 with a new optical section 10 having a correct power.
Although two engaging holes 54a are formed, one or three or more engaging holes can be formed.
In each of the aforementioned embodiments, the explanation was directed to the case in which the urging member is formed into a curved shape or a loop shape or the case in which the anterior capsule supporting portion, the posterior capsule supporting portion and the connection supporting portion are provided. However, as long as the urging member can expand the anterior capsule Sf and the posterior capsule Sb near the equator Se of the lens capsule S in the fore-and-aft direction by an urging force, any other shape or structure can be employed.
Further, although both of one end portion 201 and the other end portion 202 of the lens supporting section 20 are positioned on a linear line m1 passing the center O of the optical section 10, both of one end portion 201 and the other end portion 202 can be positioned on any other portions as long as they are positioned on opposite sides with respect to the center O of the optical section 10.
Further, although the aforementioned accommodative intraocular lens is provided with the urging member, as shown in
Further, in this embodiment, although the one end portion or the connecting portion 52, 53 or 54 of the lens supporting section 20 is provided with engaging grooves 53a or engaging holes 54a, such structure can be realized on the other end portion of the lens supporting section 20.
The terms and descriptions used herein are used only for explanatory purposes and the present invention is not limited to them. The Accordingly, the present invention allows various design-changes falling within the claimed scope of the present invention unless it deviates from the spirits of the invention.
While the present invention may be embodied in many different forms, a number of illustrative embodiments are described herein with the understanding that the present disclosure is to be considered as providing examples of the principles of the invention and such examples are not intended to limit the invention to preferred embodiments described herein and/or illustrated herein.
While illustrative embodiments of the invention have been described herein, the present invention is not limited to the various preferred embodiments described herein, but includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g., of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. For example, in the present disclosure, the term “preferably” is non-exclusive and means “preferably, but not limited to.” In this disclosure and during the prosecution of this application, the terminology “present invention” or “invention” is meant as a non-specific, general reference and may be used as a reference to one or more aspects within the present disclosure. The language present invention or invention should not be improperly interpreted as an identification of criticality, should not be improperly interpreted as applying across all aspects or embodiments (i.e., it should be understood that the present invention has a number of aspects and embodiments), and should not be improperly interpreted as limiting the scope of the application or claims. In this disclosure and during the prosecution of this application, the terminology “embodiment” can be used to describe any aspect, feature, process or step, any combination thereof, and/or any portion thereof, etc. In some examples, various embodiments may include overlapping features.
Number | Date | Country | Kind |
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2013-100932 | May 2013 | JP | national |
This is a continuation of International Application PCT/JP2014/56174, with an international filing date of Mar. 10, 2014, claiming a priority to Japanese Patent Application No. 2013-100932, filed on May 13, 2013, the contents of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
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Parent | PCT/JP2014/056174 | Mar 2014 | US |
Child | 14561891 | US |