GB2053689A

GB2053689A - Intraocular lens

Info

Publication number: GB2053689A
Application number: GB8019962A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-07-05
Filing date: 1980-06-18
Publication date: 1981-02-11
Also published as: AU5965180A; JPS5631750A; IT1127516B; DE3025272A1; IT8049177A0; NL8003692A

Abstract

An intraocular lens, having a fixation mechanism, includes a lens portion (12) having a resilient appendage (14) attached thereto at one end (16). The other end (18) of the appendage (14) slidably engages with the lens portion (12) to form a closed loop which extends from the lens portion (12) and is adjustable in its extent by the end 18 fitting into an opening 26 through the lens portion 12. The lens may have a second similar such resilient appendage 40, fixed at one end at 42, and variably engaging the lens portion 12 at its other end 48 by locating in opening 44. <IMAGE>

Description

SPECIFICATION Intraocular lens The present invention relates to an intraocular lens or pseudophakos intended for placement in either the anterior chamber or posterior chamber of an eye after removal of the natural lens thereof to counteract a cataract condition or other like conditions which destroys the functioning of the natural lens.

Intraocular lenses have been used increasingly in recent times since the use of intraocular lenses provides the cataract patient with remarkable visual acuity. In general intraocular lenses have produced excellent results. Problems still remain in placement of the pseudophakos without inflicting damage to the eye as well as ensuring continual fixation of the intraocular lens during the years following cataract surgery. There are several examples of intraocular lenses which fix to the iris. Most notably are the proposals of United States Patent No. 3,906,551 issued to Otter and United States Patent No.

4,085,467 issued to Rainin et al. The original intraocular lens development by Strampelli and Barraquer simply wedged the intraocular lens between opposite sides of the anterior chamber of thr eye immediately above the iris. The early models occasionally achieved success but were not acceptable because of fixation problems resulting from improper sizing of the lens structure, and damage to the eye during the aRer insertion of the lens, as a result of endothelial touch. The original Barraquer lens has been recently revived and has achieved greater success by the addition of springy appendages which alleviates necessity of exactly sizing the lens and insertion of a Barraquertype lens in the posterior chamber of the eye.The modern version of the Barraquer lens is known as the Shearing lens and includes a pair of hook-shaped legs which attach to the lens at points generally opposite one another.

Surgeons have found acceptable fixation in the posterior chamber in an annular notch known as the ciliary sulcus.

A Shearing lens has several disadvantages. It may be used with extracapsular surgery only. The Shear- ing lens is inserted in the posterior chamber by first inserting one appendage through the pupil to the ciliary sulcus, coiling the second appendage, and releasing the same after the lens portion and the secondary appendage has passed through the pupil to the posterior chamber to also obtain fixation at the ciliary sulcus. It has been found that the free end of the springy appendage of the Shearing lens catches eye structures during insertion and centering which adds greatly to the difficulty of insertion.

Further, a dilated pupil, which may occur spontaneously or may be medically induced post-operatively, permits the inner edge of the iris to travel under the lens since a single appendage permits bowing. In addition, problems occur in the centering of the intraocular lens beneath the pupil, since the hooklike appendage often catches on the iris, the lens capsule, and other portions of the eye. Moreover, other problems, associated with twisting about the single appendage, e.g.: the optical defect of induced cylinder, also arise.

All in all there is a need for a wedging type lens which may be easily placed in the posterior or anterior chamber of the eye, which possesses great stability, and which minimizes damage to the eye during and after insertion.

An object of the present invention is to provide an improved construction of intraocular lens wherein the above-discussed disadvantages have been obviated.

A further object of the invention to provide an intraocular lens having a fixation mechanism which may be placed in either the anterior or posterior chamber of the lens for correction of aphakia and which minimizes damage to the eye during and after insertion.

It is another object of the invention to provide an intraocular lens having a fixation mechanism which minimizes dislocation during dilation of the pupil of the eye during and after insertion of the intraocular lens within the eye.

It is yet another object of the present invention to provide an intraocular lens having a fixation mechanism which facilitates centering of the intraocular lens during the insertion process.

it is still another object of the present invention to provide an intraocular lens having a fixation mechanism which resists twisting along the axis of fixation thus preventing optical distortions within the eye such as induced cylinder.

It is another object of the present invention to provide an intraocular lens having a fixation mechanism which exhibits adjustability and stability after placement within the eye.

It is another object of the present invention to provide an intraocular lens having a fixation mechanism which is easily manufactured.

With these objects in view, the present invention provides an intraocular lens having a fixation mechanism and comprising a lens portion, a resilient appendage attached to said lens portion at one end thereof, and means for slidably engaging the other end of said resilient appendage to said lens portion.

A IE-a preferred embodiment of this intraocular lens structure includes a lens or optical zone portion which is intended for placement against the side of the iris and functions as an optical replacement for the removed natural lens of the eye. The lens includes a resilient appendage attached at one end thereof to the lens. The other end of the appendage is turned back toward the lens and slidably engages the same. Thus, a loop is formed having an end point which possesses the characteristic of having an adjustable distance in relation to the lens portion.

Such means for slidably engaging the other end of the resilient appendage may take the form of providing an opening in the lens portion for insertion of the other end of the resilient appendage. In this manner, the end of this resilient appendage slidingly engages the side portions of the opening. Thus, the opening serves as a guide for the other end of the resilient appendage.

The intraocular lens of the present invention may include a second appendage which is also attached to the lens portion. It should be noted that any of the appendages may attach to the lens or a haptic surrounding the lens portion. In this regard, the haptic may have a plurality of protuberances which are adapted for contacting the periphery ofthe iris e.g.

the angle in the anterior chamber of the eye or the ciliary sulcus in the posterior chamber of the eye.

The second appendage may also be a resilient appendage having one end attached to the lens and including means for slidably engaging the other end of the second appendage to the lens portion. Again, the means for engaging the other end ofthe second resilient appendage may also take the form of an opening in the lens portion for guiding engagement of the other end of the second appendage.

The invention of the present application may also embrace an embodiment where the opening in the lens portion extends completely through the lens to form a tunnel having first and second entrances thereto. The appendage attached to the lens portion may then extend through the tunnel such that a first portion of the appendage lies outside the lens between the attachment of one of the appendage to the lens and the first entrance to the tunnel. Also, an intermediate portion of the appendage is positioned within the tunnel and a third portion extends outside the second entrance to the tunnel. In a further variation there is a second opening in the lens slidably to engage the other end of the appendage orto guide relative movement between the other end of the appendage and the lens portion.

The invention may include another embodiment wherein the second appendage is a resilient appendage having a point of attachment to the lens portion at one end thereof and including means for slidably engaging the other end of the second appendage or guiding movement of the other end of the second appendage in relation to the lens portion. In this case, the means for slidably engaging the other end of the first and second appendages may comprise a pair of openings each sized for insertion of one ofthe first and second resilient appendages. The first and second resilient appendages in this case may also have the first ends attached within one of the pair of openings. This embodiment reduces the labour required to produce a usable lens.

In essence, the lens of the present invention includes a lens portion having an appendage attached thereto in one end thereof, and means for guiding movement of the appendage relative to the lens portion.

Differently expressed, the lens of the invention is an intraocular lens having a fixation mechanism including a lens portion or optical zone with a resilient appendage attached to the lens portion at one of its ends. Means is provided for slidably engaging the other end of the resilient appendage to the lens portion.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which:~ Fig. 1 is an enlarged elevation of an embodiment of the lens ofthe invention, adjustable appendages thereof being depicted in phantom lines; Fig. 2 is an enlarged sectional side view of a human eye, showing the lens of Fig. 1 fretted within the posterior chamber ofthe eye; Fig. 3 is an elevation of another embodiment of the lens ofthe invention; Fig. 4 is an elevation of a third embodiment of the lens ofthe invention; Fig. 5 is an elevation of a fourth embodiment of the present invention; Fig 6 is an elevation of yet another embodiment of the lens of the present invention;; Fig. 7 is a sectional side view of a human eye showing the lens of Fig. fitted in the posterior chamberofthe eye; and Fig.8 is an elevation of another embodiment of the lens of the present invention.

Referring firstly to Figs. 1 and 2,the embodiment of the lens of the invention illustrated therein is indicated as a whole by the reference numeral 10 and includes as one of its elements an optical lens portion or optical zone 12 which may be formed from methylmethacrylate, quartz, opthalmic glass or other suitable materials known in the art. Of course, the lens portion 12 must be biologically inert and transparent such that optical correction may inure. A first appendage 14 includes a first end 16 which is attached to the lens portion 12 by gluing, sonic welding or other suitable process known in the art. The first appendage 14 may be integrally moulded with the lens portion 12. The appendage 14 also includes a second end 18 and an intermediate portion 20 between the ends 16 and 18.The lens also includes, as one of its elements, means 22 for guiding movement ofthe end 18 in relation to the lens portion 12. This means 22 may take the form of means 24 for slidably engaging the end 18 with the lens portion 12. In this embodiment the means 22 and 24 is in the form of an opening 26 in the lens portion 12 sized for insertion of the end 18 ofthe appendage 14 therein. Any force on the intermediate portion 20 of the appendage 14 will cause the end 18 to slide further into the opening 26. The intermediate portion 20 would then move toward the lens portion by a distance shown by arrows 28 (Fig. 1).

Turning to Figs. 3 and 4, these show two further embodiments of the lens of the invention In Fig. 3, appendage 14A is attached to lens portion 12 at end l6Abythe same methods described in relation to appendage 14 above. Means 22 may take the form of an opening 30 which extends ortunnelsthroughthe lens portion 12. End 32 of the appendage 14A fits within another opening 34 which may or may not extend through the lens portion 12. As shown in Fig.

3, the opening 34 does extend through the lens portion 12 for convenience of manufacture. Turning to Fig. 4, it may be seen that appendage 14B attaches to lens portion 12 at end 16B. Opening 30 guides the remaining portion ofthe appendage 14B in relation to the lens portion 12. However, the end 36 of the appendage 14B is free, having a cap 38 for the pur pose of preventing puncturing the eye structure.

Returning to Fig. 1, it may be seen that the embodiment depicted therein includes a second appendage 40 which is fixed to the lens portion 12 at its end 42.

This second appendage 40 has means 44 for guiding movement of the remaining portion 46 of the appendage 40, including its end 48. As will be under- stood, the appendages 14, 14A, 14B and 40 may be resilient. This permits flexure thereof upon the application of pressure between their ends.

In this connection, attention is drawn to Fig. 2 which depicts the intraocular lens 10 fitted within posterior chamber 50 of a human eye 52. As can be seen, the first appendage 14 and the second appendage 40 located in the annular notch 54 known as the ciliary sulcus. The means 22 and 44 for guiding the remaining portions of the appendages 14 and 40 (apart from the fixed ends 16 and 42 respectively) permit the appendages 14 and 40 to shorten the distance indicated by the arrows 28 and 56, (Fig.1). In the case where the appendages 14 and 40 are resilient, such shortening will result in the application of pressure by the appendages on the ciliary sulcus 54 which tends to hold the intraocular lens 10 in place.

Fig. 2 depicts an extra capsular cataract removal where the shell of natural lens 58 remains attached to zonules 60. Since the appendages 14 and 40 form a closed loop, many of the disadvantages of the open loop appendage system have been eliminated, yet the adjustablilty afforded by the former open loop system has been retained.

Turning now to Fig. 5, another embodiment of the intraocular lens of the present invention is shown wherein an appendage 14C forms an end 16C attached to the lens portion 12. Means 22 takes the form of an opening 62 which may extend through the lens portion 12, through haptic 64, or both. As shown in Fig. 5, the opening 62 extends through the lens portion 12. This opening 62 may be constructed to extend only partially through the lens portion 12.

The haptic 64 includes a pair of protuberances 66 and 68 which are intended for contact with ciliary sulcus 54 or angle 70 (anterior chamber placement) (Fig. 1). This embodiment provides three point fixation within the posterior or anterior chamber of eye 52, contact being made by protuberances 66 and 68 and by a rounded portion 72 of the looped appendage 14C. Of course, the appendage 14C is extensible and retractable in the same manner as the loop 14 of the embodiment of Fig. 1.

In the embodiment of Figs. 6 and 7, appendage 14 is substantially identical to that depicted in Fig. 1.

Opening 26 includes a first entrance 72 and a second entrance 74. Appendage 76 is attached to lens 12 at end 78. This appendage 76 includes a first portion 80 which extends through pupil 84 of eye 52 (Fig. 7).

Second portion 86 of the appendage 76 is adapted for passing through an iris opening 88 which may be provided during cataract surgery. Enlarged end portion 89 extends to the periphery of iris 82 for engagement with, e.g. the ciliary sulcus 54. A cap 38 blunts the end of appendage 76 to prevent damage to the internal structure of the eye during and after insertion of the second appendage 76. Surgical tweezers 90 may be used to stabilize the intraocular lens 10 during insertion (Fig. 7).

With reference to Fig. 8 another embodiment of the lens of the invention is illustrated in which a first appendage 92 and a second-appendage 94 both include means 22 for guiding the appendages in any movement relative to the lens portion 12. The means 22 takes the form of a pair of openings 96 and 98 which extend through the lens portion 12. First ends 100 and 102 of the appendages 92 and 94 respectively are fixed within openings 96 and 98 by known methods such as sonic welding, fusion, or the like.

Second ends 104 and 106 slidingly engage the side portions of the openings 96 and 98. Thus, bent portions 108 and 110 of the appendages 92 and 94 lie at an adjustable distance from the lens portion 12.

Where the appendages 92 and 94 are resilient, any pressure on the same will result in a spring action which tends to force the appendages 92 and 94 into their original position as depicted in Fig. 8.

It will be apparent that each of the embodiments described hereinabove includes an appendage 14, extending from its lens portion 12, which forms a closed loop in relation to the lens portion, means 22 for guiding the movement of the appendage 14 in relation to the lens portion 12, and means 112 (Fig. 1) for urging the appendage 14 away from the lens portion 12. The means 112 may simply be realised by the appendage 14 having resilience of springiness such that any pressure on the appendage 14 towards the lens portion 12 will result in the means 112 coming into play.

In operation, the user inserts the intraocular lens 10 into the anterior or posterior chamber of the eye 52, employing the angle 70 orciliary sulcus 54 atthe periphery of the iris 82to obtain a confing surface for the first appendage 14A or 14B or the first appendages 14, 140 or 92 in combination with the second appendages 40,76,96 or the haptic 64.

While in the foregoing specification various embodiments of the invention have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, it will be apparent to those of ordinary skill in the art that changes may be made in such detail without departing from the scope of the invention as defined in the following claims.

Claims

1. An intraocular lens having a fixation mechanism and comprising a lens portion, a resilient appendage attached to said lens portion at one end thereof, and means for slidably engaging the other end of said resilient appendage to said lens portion.

2. An intraocular lens as claimed in claim 1 in which said means for slidably engaging the other end of said appendage comprises an opening in said lens portion for insertion of said other end of said resilient appendage.

3. An intraocular lens as claimed in claim 1 or 2 in which said resilient appendage is a first appendage and which additionally comprises a second appendage attached to said lens portion.

4. An intraocular lens as claimed in claim 1,2 or 3 in which said lens portion includes a haptic having a plurality of protuberances adapted for contacting the periphery ofthe iris.

5. An intraocular lens as claimed in claim 2, in claims 2 and 3, or in claims 2 and 4, in which said opening in said lens portion extends therethrough to form first and second entrances to said opening through said lens portion, said resilient appendage extending through said opening through said lens portion such that a first portion of said resilient appendage lies between said one end of said resi lient appendage attached to said lens portion and said first entrance to said opening through said lens portion, an intermediate portion of said appendage lies within said opening through said lens portion, and a third portion of said appendage extends outside said second entrance to said opening through said lens portion.

6. An intraocular lens as claimed in claim 5 in which said opening through said lens portion is a first opening, and which additionally comprises a second opening which slidably engages said other end of said resilient appendage.

7. An intraocular lens as claimed in claim 3, or in claims 4, 5 or 6 when appendantto claim 3, in which said second appendage is a resilient appendage.

8. An intraocular lens as claimed in claim 7 in which said second appendage is attached to said lens portion at one end thereof, and which additionally comprises means for slidably engaging the other end of said second appendage to said lens portion.

9. An intraocular lens as claimed in claim Bin which said means for slidably engaging the other end of said first resilient appendage and said means for slidably engaging the other end of said second appendage comprise a pair of openings, each opening for insertion of one of said first and second resilient appendages.

10. An intraocular lens as claimed in claim 9 in which said first ends of said first and second resilient appendages each attach to said lens portion within one of said pair of openings.

11. An intraocular lens as claimed in claim 3 in which said second appendage has a first portion extending from said lens portion, a second portion intended for passing through the iris opening and an enlarged end portion intended for extending to the periphery of the iris for engagement therewith.

12. An intraocular lens having a fixation mechanism and comprising a lens portion, an appendage attached to said lens at one end thereof, and means for guiding movement of a remaining portion of said appendage relative to said lens portion.

13. An intraocular lens as claimed in claim 12 in which said appendage is a first appendage and which further comprises a second appendage having a first portion extending from said lens portion, a second portion intended for passing through an iris opening and an enlarged end portion intended for extending to the periphery of the iris for engagement therewith.

14. A fixation mechanism, for an intraocular lens having a lens portion, said mechanism comprising an appendage extending from said lens portion, and forming a closed loop in relation to said lens portion, means for guiding movement of a portion of said appendage in relation to said lens portion, and means for urging said appendage away from said lens portion.

15. An intraocular lens having a fixation mechanism substantially as hereinbefore described with reference to and illustrated in Figs. 1 and 2, in Fig. 3, in Fig. 4, in Fig. 5, in Figs. 6 and 7 or in Fig.8 ofthe accompanying drawings.