1. Field
This disclosure relates generally to intraocular lenses, and, more particularly, to intraocular lens fixation.
2. Background
Intraocular lens implants (“IOLs”) are commonly used to replace the natural lens of the human eye when warranted by medical conditions, such as cataracts. These processes typically involve the removal of the natural lens from the capsular bag through the cornea of the eye, and the subsequent insertion of the IOL into the capsular bag. The IOLs are usually stabilized within the capsular bag by haptic arms that extend outward from the IOL. In some cases, the IOLs may later become dislocated due to, for example, problems with the capsular bag or the zonules that hold it in place, or due to a malpositioned haptic. As a result, a second surgery is necessary to reposition the dislocated lens and may require suturing of the IOL in place through the iris.
In one aspect of this disclosure, an intraocular lens fixation device is disclosed for affixing a portion of an intraocular lens haptic to an iris of an eye. The device comprises a clip made of a biologically inert, deformable material. The clip includes at least two spaced apart arms extending from a back portion of the clip, the spaced apart arms at their distal ends prior to deployment being slightly wider than the portion of the intraocular lens haptic. Each arm has a length that exceeds a combined thickness of the portion of the intraocular lens haptic and the iris at a location where the arm passes through the iris. The clip being positioned with the back portion on a side of the iris opposite the haptic portion and a substantial part of the length of the arms being on a haptic-side of the iris with the arms each being located on opposing sides of the portion of the intraocular lens haptic and deformed such that (i) the distal ends of the arms are spaced narrower than the portion of the intraocular lens haptic, and (ii) the back portion and arms collectively surround and constrain, within an interior surface of the clip, both a section of the iris and the portion of the haptic, thereby affixing the iris and intraocular lens haptic to each other.
In another aspect of this disclosure, an intraocular lens fixation system is disclosed. The system comprises a clip including at least two arms, the clip being made of a biologically inert, deformable material. The arms of the clip are spaced apart at their ends so as to form a gap that is slightly larger than a portion of an intraocular lens haptic that will be affixed to an iris of an eye using the clip. A microforcep tip having a pair of opposed jaws each including distal ends, the jaws being configured to hold the clip therebetween. Either (a) the ends of the arms, (b) distal ends of the jaws, or (c) both, are sharpened to facilitate piercing of the iris to either side of the portion of the haptic. In addition, the jaws and clip are aligned relative to each other to allow for piercing of the iris and insertion of the arms of the clip through the iris such that when the arms of the clip have passed through the pierced iris, the arms will flank the portion. The jaws of the microforcep tip are further configured to be able to apply a compressive force to the arms sufficient to cause the clip to deform such that the ends of the arms on a side of the haptic opposite the iris move towards each other and thereby cause the clip to affix the haptic to the iris at the portion.
In yet another aspect of this disclosure, a method of affixing an intraocular lens within an eye of a patient is disclosed. The intraocular lens includes at least two haptics located on a side of the patient's iris opposite the cornea. The method comprises piercing the iris in at least two locations that closely flank a portion of one of the haptics. An arm of a biologically inert deformable clip is inserted through each of the piercings in the iris until a distal end of each arm is located on opposing sides of the portion of one of the haptics. A force is applied to each of the arms so as to deploy the clip by causing the distal ends of the arms to approach each other and substantially surround and constrain, within an interior surface of the clip, both a section of the iris that is between the arms and the portion of one of the haptics.
The foregoing and following discussion outlines rather generally the features and technical advantages of one or more embodiments of this disclosure in order that the following detailed description may be better understood. Additional features and advantages of this disclosure will be described herein and may be the subject of claims of this application.
This disclosure is further described in the detailed description that follows, with reference to the drawings, in which:
In simplified overview, to avoid the time consuming and difficult suture-based approach to fixation of IOL haptics to the iris, the instant disclosure describes an approach whereby a clip is deployed through the iris that affixes the haptic to the iris. The clip is made deformable so that, once arms of the clip are inserted through the iris, the clip can be deformed in place and thereby affix a haptic of the IOL to the iris in a way analogous to the way a staple can hold multiple pieces of paper together.
Implementations of the device and method described herein can provide advantages over many conventional methods for correcting dislocated IOLs. For example, some implementations of the disclosed device and method enable repair of a dislocated IOL merely by repositioning of the IOL (i.e., without requiring removal of the old dislocated IOL). Similarly, some implementations will be superior to suturing the haptic arms to the iris because suturing is much more difficult to perform, less durable over time, and carries much greater risk for younger patients. In contrast, implementations of the methods described herein are relatively easy to perform and require far less skill than suturing approaches, and implementations of the device can be much more durable than suturing approaches.
The above will become evident from the following description.
In instances where an IOL 202 becomes dislodged, repositioning alone may not be sufficient to avoid another dislocation in the future. Moreover, in some cases, the internal eye structures necessary to support the haptics 206, 208 may be damaged or otherwise incapable of doing so.
In such cases, an approach and device described herein permits the IOL 202 to be repositioned and used without the need for removal of the IOL or the difficulty associated with the current iris suture technique.
As noted above, deployment of a clip requires that the clip be deformed to a new position, which, as noted above, will serve to affix a haptic of an IOL to the iris. As a result, depending upon the particular implementation, as well as the material used for the clip, it may be desirable to specifically control the location(s) where the deformation takes place. This can be accomplished by, for example, weakening or otherwise pre-deforming a part of the clip in such a manner as will result in the clip deforming uniformly and/or in those areas first.
For example,
Depending upon the particular implementation used for the clip, the recess(es) or discontinuity/(ies) that act as a deformation control crease can be created by cutting, molding, forging, deforming, etc. Alternatively, any other known way of controlling or confining bending of a solid within a prescribed area, which will still allow the clip to perform its intended purpose, can be used. Similarly, different shaped clips can be used, the clips of
Having described various aspects and illustrative clips suitable for use with the approach described herein, a device for the deployment of a clip will now be described.
As noted above, deployment of a clip requires essentially two capabilities: (1) an ability to pierce the iris, and (2) an ability to deform the clip when appropriately positioned.
In general, the maximum width of the microforcep tip with the clip contained therein, measured along the portion that will be introduced into the eye, should be less than the width of a sutureless corneal incision, which is generally about 2.75 mm wide, to ensure that it can be used in connection with such incisions. Of course, larger incisions will allow for larger microforcep tip widths, even if such a corneal incision would require suture closure.
It is worthwhile noting that, although less desirable, the distal ends of both the clip and microforcep tip can be blunt. However, with such blunt embodiments, some other means of piercing the iris as described herein (for example a needle) will be necessary and the complexity and risk associated with the procedure will be greater. Nevertheless, such variants are contemplated as being within the scope of the subject matter described herein.
In general, a microforcep tip is essentially a modified version of a conventional microforcep or microscissor, specifically one where, in the case of a microforcep, the jaws are modified or grooved to hold the clip and allow for sufficient but not excessive force to be transferred to the arms of a clip as described herein to meet the above requirements for deploying the clip. In the case of a microscissor, the blades may be made thicker and the cutting surfaces dulled to preclude slicing of the iris tissue and an appropriate recess or other form of constraining the clip prior to and during deployment would be included therein.
Microforcep or microscissors suitable for modification to accomplish deployment of a clip as described herein are commercially available from numerous sources including, for example: Accutome Inc., 3222 Phoenixville Pike, Malverne, Pa. 19355; Alcon Laboratories Inc., 6201 South Freeway, Fort Worth Tex. 76134; ASICO LLC, 26 Plaza Drive, Westmont, Ill. 60559; Bausch & Lomb Surgical, 30 Enterprise, Suite 450, Aliso Viejo, Calif. 92656; Dutch Opthalmic USA, 10 Continental Drive, Exeter, N.H. 03833; Geuder AG, Hertzstrasse 4, 69216 Heidelberg, Germany; and Pelion Surgical, 1525 Sunshine Court, Aiken, S.C. 29803.
In addition, in some implementations, the microforcep tip is a permanent part of a deployment device, whereas with other implementations, the microforcep tip is attachable/detachable.
Advantageously, where the microforcep tip 1006 is removable, the microforcep tip 1006 can be separately provided in sterile packaging with the clip pre-loaded in a single-use configuration. Alternatively, the components can be provided such that the clip must be loaded into the microforcep tip 1006 and properly oriented within the jaws prior to use. In such a case, given the sizing involved, the groove or recess can be specifically shaped such that when the clip is inserted it snaps into place with the proper alignment.
Having generally described the various components, a preferred iris fixation process will now be described with reference to
To perform the affixation, the surgeon first locates a haptic arm 206 of the IOL and makes sure that it is positioned appropriately underneath the iris 106 in, for example, the conventional manner as would be used for a suturing affixation technique. Then, the clip 800 is positioned above the iris 106 and the portion of the haptic arm 206 to be used to secure the IOL such as shown in
The process can then be repeated with a new clip for each additional IOL haptic that has not yet been secured to the iris 106 as described above.
It should be understood that this description (including the figures) is only representative of some illustrative embodiments. For the convenience of the reader, the above description has focused on a representative sample of all possible embodiments, a sample that teaches the principles of the invention. The description has not attempted to exhaustively enumerate all possible variations. That alternate embodiments may not have been presented for a specific portion of the invention, or that further undescribed alternate embodiments may be available for a portion, is not to be considered a disclaimer of those alternate embodiments. One of ordinary skill will appreciate that many of those undescribed embodiments incorporate the same principles of the invention as claimed and others are equivalent.