Method of preparing a multielement intraocular lens for insertion
A method of folding a multiple element IOL comprising folding the first lens element and second lens element such that the second lens element at least partially surrounds the first lens element and such that, after folding, both the first lens element and the second lens element are substantially aligned along the optical axis. A hinged apparatus such as a cartridge may be used to cause the second lens element to be folded. A method of loading a multielement IOL comprising folding the haptics such that a portion of the haptics contacts an exterior side of one of the first lens element and the second lens element.
The present invention relates to a method of preparing an intraocular lens for insertion, and more particularly to a method of preparing a multielement intraocular lens for insertion.
BACKGROUND OF THE INVENTIONIn response to the sharpness of the image received by the retina, the brain operates to contract or relax ciliary muscle 26. Ciliary muscle 26 is disposed within ciliary body 28, and upon contraction of the ciliary muscle, the ciliary body is caused to move. To achieve near-focus accommodation, the ciliary muscle is contracted thereby causing the ciliary body to relax tension on zonules 27 which permits the capsular bag and crystalline lens 17 to become more rounded. To achieve far focus (i.e., disaccommodation), the ciliary muscle is relaxed thereby increasing tension on zonules 27 which causes the capsular bag and crystalline lens 17 to become flatter.
In an eye where the natural crystalline lens has been damaged (e.g., clouded by cataracts), the natural lens is no longer able to properly focus and/or direct incoming light to the retina. As a result, images become blurred. A well known surgical technique to remedy this situation involves removal of a damaged crystalline lens. The lens is removed by first making an incision in the cornea, and then making a hole in the capsular bag known as a capsularhexis (also referred to simply as a rhexis). The crystalline lens is removed through the rhexsis and through the incision. Subsequently, an artificial lens known as an intraocular lens (IOL) can be placed into the evacuated capsular bag through incision and through the rhexis.
Conventional IOLs are typically fixed-focus lenses. Such lenses are usually selected to have a power such that the patient has a fixed focus for distance vision, and the patient requires spectacles or contact lenses to permit near vision. In recent years extensive research has been carried out to develop IOLs having variable focus capability. Such IOLs are known as accommodating IOLs (AIOLS). The term AIOLs refers to both single-element and multielement lens systems.
AIOLs permit a wearer to have accommodative vision. AIOLs are typically located in the posterior chamber (e.g., in the capsular bag) and provide variable focal power in accordance with tension or a lack of tension exerted on the capsular bag 16 as a result of contraction and relaxation of the ciliary muscle.
To date, although there have been numerous patent filings directed to multielement AIOLs, there have been few filings related to insertion techniques for delivering such AIOL into an eye. Furthermore, those techniques that have been described to date, which include an injector device, have required substantially completely newly designed for implanting AIOLs into patients' eyes.
In addition to multielement AIOLs, multielement non-accommodative IOLs have been proposed. Similar to AIOLs, there have been few filings related to insertion techniques for delivering such multielement IOLs into an eye.
SUMMARYAspects of the present invention are directed to folding techniques for use in reducing the cross-sectional shape of multielement IOLs (i.e., accommodative and non-accommodative IOLs) for insertion into an eye. Other aspects of the present invention are directed to techniques for loading an IOL inserter with a multielement IOL for subsequent insertion into an eye.
A first aspect of the invention is directed to a method of facilitating loading a multielement IOL into an injector, the IOL having a plurality of haptics coupling a first lens element and a second lens element, the haptics extending beyond a periphery of at least one of the first lens element and the second lens element, the method comprising folding at least one of the haptics radially inward while the first lens element and the second lens element are substantially aligned along the optical axis.
In some embodiments, the step of folding at least one haptic comprises folding at least one of the haptics such that it is at least partially disposed between the first lens element and the second lens element. In other embodiments, the step of folding at least one haptic may comprise folding at least one haptic such that a portion of the at least one haptic contacts an exterior side of one of the first lens element and the second lens element.
In some embodiments, the step of folding at least one haptic comprises folding at least two of the haptics radially inward. In some of such embodiments, the multielement IOL may comprise at least three haptics. In some of such embodiments, the step of folding at least two of the haptics comprises folding at least two haptics such that they are at least partially disposed between the first lens element and the second lens element. In other of such embodiments, the step of folding at least one haptic comprises folding at least two haptics such that a portion of the haptics contacts an exterior side of one of the first lens element and the second lens element.
In some embodiments, the step of folding the two haptics is achieved using a first arm and second arm of a forceps or tweezers.
In some embodiments, the method further comprises a step of locating the IOL in a staging area of an inserter, with at least the second lens element contacting the inserter. In some embodiments, the staging area comprises a cover, and the cover is operated to maintain the haptics in a folded state after the IOL is located in the staging area. In some embodiments, the method further comprises pushing the first lens element and the second lens element together, prior to the step of folding the haptics.
Illustrative, non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which the same reference number is used to designate the same or similar components in different figures, and in which:
Subsequently, also as illustrated in
It is to be appreciated that although folding of the first lens element is illustrated as occurring with the use of two forceps, in other embodiments, folding may be achieved by the use of human hands without forceps, or with tweezers or with any other suitably configured apparatus. In some embodiments, folding can be achieved using a combination of any of forceps, fingers or tweezers.
It will also be appreciated that, after folding the second lens element such that the second lens element at least partially surrounds the first lens element, IOL 40 is substantially reduced in profile, such that the IOL can be inserted into a much smaller corneal incision than if the IOL were not so folded. According to one technique, forceps 120 can be removed after lens element 44 is folded; the first lens element 42 and the second lens element 44 are maintained in a folded state with forceps 130. Forceps 130 may then be used to inserter the IOL into an eye.
In some embodiments, the posterior lens element can be folded first (i.e., the posterior lens element is the second lens element 44). In such embodiments, the anterior lens element is folded such that it at least partially surrounds the posterior lens element. In other embodiments, the anterior lens element can be folded first (i.e., the anterior lens element is the second lens element.) In such embodiments, the posterior lens element will be folded such that it at least partially surrounds the posterior lens element. In some embodiments, it is advantageous to fold the less massive lens element first and to fold the more massive lens element so as to at least partially surround the less massive lens element.
As illustrated in
In some instances, upon closing hinged apparatus 50 of the illustrated embodiment, a portion of the first lens element and/or the haptics may become trapped between portions 52 and 54 of the hinged apparatus. In such instances, a forceps or other suitable device may be used to press the first lens element and/or haptics into the lumen.
It will be appreciated that after folding the second lens element such that the second lens element is at least partially surrounds first lens element, the IOL 40 is substantially reduced in profile, such that the IOL can be inserted into a much smaller corneal incision and/or rhexis than if the IOL were not so folded. As discussed above, the first lens element can be the anterior lens element or the posterior lens element, and the other of the anterior lens element and posterior lens element is the second lens element.
Hinged apparatus 50 may be any suitable hinged apparatus. For example, the hinged apparatus may be a conventional IOL inserter cartridge. In some embodiments, the cartridge may be a winged cartridge. In embodiments where the hinged apparatus is a cartridge, after closing of the cartridge, the lumen may be aligned with the lumen of the injector (not shown) and the IOL inserted into a patient's eye by actuating a plunger (not shown). In some embodiments, the lumen of the inserter may be tapered such that the IOL is further compressed as the IOL is pushed along the lumen by the plunger into the eye.
In some embodiments, the hinged apparatus may be a holder/folder apparatus. In such embodiments, the IOL may be removed from the holder/folder apparatus after folding and then located in an appropriate injector device or directly into a patient's eye using forceps.
An advantage of the folding techniques discussed above is that contact between the surfaces of the first lens element and the second lens element is limited; and the folding of the lenses provides substantial potential energy, such that when the IOL is released from its folded (i.e., stressed) state, the first lens element and the second lens element readily separate from one another. That is, they overcome any cohesion between the lenses and readily attain an unstressed state.
Although a winged cartridge was discussed above, other types of cartridges may be used. For example, a cartridge may be a hingeless, rear-loaded cartridge, such as cartridge 310 shown in
According to some techniques, loading of IOL 40 into cartridge 310 is performed with forceps 120. According to one example of a loading technique, forceps 120 can be used to grasp the first lens element 42 as shown in
Before the IOL 40 is inserted into cartridge 310, the loading area is typically lubricated by depositing an amount of viscoelastic. The loading area 320 comprises a passageway which is cylindrical in cross section (or other appropriate shape) and gradually decreases in diameter in the direction of tip 352. In some embodiments, the loading area 320 is formed with a slot 336 so that once the IOL is inserted in the staging area 334, the forceps can easily be withdrawn. According to some techniques, the IOL may be inserted loading area through slot 336.
As shown in
A pair of ridges 340 may be formed on the inner surface of at least a portion of the length of the walls which define the loading area 320 for guiding the outer edges of second lens element 44. In some embodiments, the edges of the second lens element are inserted beneath the ridges 340. As shown, in particular in
The staging area 334 is formed with a passageway that operates as a continuation of the passageway in the loading area 320. In some embodiments, the staging area passageway also gradually diminishes in size along its length. After the IOL 40 is loaded in the cartridge as described and shown, the lumen may be aligned with the lumen of an injector (not shown) using handle 348. Subsequently, the IOL can be pushed through tip 352 and inserted into a patient's eye by actuating a plunger (not shown). It is to be appreciated that, in some embodiments, the first lens element and the second lens element are maintained on the optical axis throughout the loading and insertion process.
U.S. Pat. No. 6,214,015 issued Apr. 10, 2001 to Reich, et al. includes further details of a rear-loaded cartridge that may be used to fold a multielement IOL according to aspects of the present invention. The substance of said patent is hereby incorporated by reference.
Although the technique described above included folding the first lens element such that outer portions of the first lens element are displaced towards the second lens element prior to loading the AIOL into the cartridge in other embodiments, according to other techniques, the first lens element may be folded such that outer portions of the first lens element are displaced away from the second lens element prior to loading the AIOL into the cartridge (in the manner shown in
In a manner similar to what was described above, the IOL is then inserted directly into the proximal end 322 of the loading area 320. As the IOL is pushed toward the staging area 334, the walls which define the loading area operate to cause the edges of second lens element 44 to curl upwardly. As the IOL is pushed toward the staging area 334, the diminishing-diameter surface of the loading area 320 causes second lens element 44 to deform and compress while the first lens element 42 is held by the forceps.
In
In some embodiments, the step of pressing the first lens element 42 and second lens element 44 toward one another is performed with the second lens element being disposed on a cartridge (see hinged apparatus 50 illustrated in
It is to be appreciated that although folding is illustrated as occurring with the use of a forceps and a cartridge, in other embodiments, folding may be achieved using forceps, fingers or tweezers or a combination thereof.
In some embodiments, preparing a multielement IOL for insertion includes loading the IOL into an IOL inserter. One example of an IOL suitable for such techniques is the IOL that was discussed above with reference to
In
It should be appreciated that the haptics may be folded (i.e., folded such that a portion of the haptics contacts an exterior side of one of the first lens element and the second lens element) using any suitable technique. According to some techniques, as illustrated, the IOL may be folded while the IOL is disposed on a shelf in the staging area of an inserter. In other examples of techniques, it is advantageous if the haptics are folded while the IOL is disposed on a suitable surface and subsequently transferred to a staging area of an inserter. For example, the haptics may be folded while the IOL is disposed on a table top or on a separate folding apparatus or on portion of the packaging material in which the IOL.
Although separate steps of pushing the lens elements together and folding the haptics are illustrated, it is to be appreciated that such steps may be achieved in a single step. For example, the forceps may be manipulated to fold the IOL such that a portion of the haptics contacts an exterior side of the first lens element while pushing the first lens element toward the second lens element. Also, it is to be appreciated that by moving the haptics, the first lens element will naturally move toward the second lens element another. Further, in some embodiments, the haptics may extend toward the exterior side of the fist lens element when the IOL is in an unstressed state (i.e., the first lens element is recessed relative to the haptics) thus facilitating folding the haptics such that a portion of the haptics contacts an exterior side of a lens element, and such that the lens elements are pressed together as the haptics are folded.
In some embodiments, haptics 46a and 46b are folded to be substantially entirely within periphery P. However, the invention is not so limited and in some embodiments, the haptics are only partially within the periphery P. Furthermore, although in
In some embodiments of the above technique, the first lens element 42 is an anterior lens element of an IOL. In such embodiments, the haptics 46a and 46b contact an anterior side of the anterior lens element (when folded as shown in
In other embodiments, the first lens element 42 is a posterior lens of the IOL. In such embodiments, the haptics 46a, 46b are folded such that a portion of the haptics contacts a posterior side of the posterior lens element. For example, in such embodiments, IOL 40 is placed on shelf 129 with the anterior lens element disposed on the surface and the posterior lens element above the surface. Subsequently, the haptics are folded onto the posterior side of the posterior lens element.
In some embodiments, haptics 46a and 46b are folded to be substantially entirely within periphery P. However, the invention is not so limited and in some embodiments, the haptics are only partially within the periphery P. Furthermore, although in
It is to be understood that although the IOL in the embodiments discussed above has three haptics, the aspects of the invention (illustrated in
In the illustrated embodiment, distal portion 122 is subdivided into three graduated sections 197-199. The proximal section 197 has a generally rectangular configuration and defines an inner cavity 101 sized to matingly receive proximal member 116, including cover 121. Section 197 functions to hold cover 121 against shelf segment 129.
The medial section 198 of distal portion 122 is significantly smaller than proximal section 197 so that a rim 162 is defined therebetween. Rim 162 acts as a shoulder in abutment with the aligned distal ends 128, 111 of proximal member 116 and cover 121. The inner wall of medial section 198 converges to define a funnel shaped passage 112. In some embodiments, the funnel portion 112 has an oval cross section, although other shapes could be used. This funnel section causes the lens to become further folded and/or compressed for entry into the eye.
The distal section 199 of distal portion 122 is a long, narrow tube which defines an inner lumen 114. Distal section 199 is to be inserted through the narrow incision made in the eye. As with medial section 198, distal section 199 and lumen 114 may have an oval cross sectional shape. Of course, other shapes could be utilized. To facilitate manufacturing and further compression of an IOL, lumen 114 is formed to taper slightly as it extends forward. Tip 195 of distal portion 122 may be beveled (e.g., at 45 degrees to the longitudinal axis of the inserter lumen) to ease the insertion of the distal portion into the incision and to assist in facilitating a gradual expansion of the lens as it exits from lumen 114. For example, the PS30-II is suitable for inserting an IOL through an incision having a size of 3.0 mm.
Although
Referring to
As discussed above, an advantage of this folding technique is that contact between the surfaces of the first lens element and the second lens element is limited; and the folding of the lenses provides substantial potential energy, such that when the IOL is released from its folded (i.e., stressed) state, the first lens element and the second lens element readily separate from one another. That is, they overcome and cohesion between the lenses and readily attain an unstressed state. Viscoelastic assists in separation of the lens elements.
Having thus described the inventive concepts and a number of exemplary embodiments, it will be apparent to those skilled in the art that the invention may be implemented in various ways, and that modifications and improvements will readily occur to such persons. Thus, the embodiments are not intended to be limiting and presented by way of example only. The invention is limited only as required by the following claims and equivalents thereto.
Claims
1. A method of facilitating loading a multielement IOL into an injector, the IOL having a plurality of haptics coupling a first lens element and a second lens element, the haptics extending beyond a periphery of at least one of the first lens element and the second lens element, the method comprising:
- folding at least one of the haptics radially inward while the first lens element and the second lens element are substantially aligned along the optical axis.
2. The method of claim 1, wherein the step of folding at least one haptic comprises folding at least two of the haptics radially inward.
3. The method of claim 2, wherein the multielement IOL comprises at least three haptics.
4. The method of claim 1, wherein the step of folding at least one haptic comprises folding at least one of the haptics such that it is at least partially disposed between the first lens element and the second lens element.
5. The method of claim 2, wherein the step of folding at least two of the haptics comprises folding at least two haptics such that they are at least partially disposed between the first lens element and the second lens element.
6. The method of claim 1, wherein the step of folding at least one haptic comprises folding at least one haptic such that a portion of the at least one haptic contacts an exterior side of one of the first lens element and the second lens element.
7. The method of claim 2, wherein the step of folding at least one haptic comprises folding at least two haptics such that a portion of the haptics contacts an exterior side of one of the first lens element and the second lens element.
8. The method of claim 2, wherein the step of folding the two haptics is achieved using a first arm and second arm of a forceps or tweezers.
9. The method of claim 2, further comprising a step of locating the IOL in a staging area of an inserter, with at least the second lens element contacting the inserter.
10. The method of claim 9, wherein the staging area comprises a cover, and the cover is operated to maintain the haptics in a folded state after the IOL is located in the staging area.
11. The method of claim 9, further comprising pushing the first lens element and the second lens element together, prior to the step of folding the haptics.
12. The method of claim 9, wherein the first lens element is an anterior lens element and the second lens element is a posterior lens element.
13. The method of claim 9, wherein the first lens element is a posterior lens element and the second lens element is an anterior lens element.
14. The method of claim 9, wherein the second lens element is more massive than the first lens element.
15. The method of claim 1, further comprising actuating the IOL inserter to insert the IOL into an eye.
16. The method of claim 15, the step of actuating the IOL inserter results in compression of the IOL prior to insertion in the eye
17. The method of claim 15, the step of actuating the IOL inserter comprises advancing the IOL over at least two ramps.
Type: Application
Filed: Oct 20, 2006
Publication Date: Apr 24, 2008
Inventors: Emin Engin (Rochester, NY), Gary A. Richardson (Rochester, NY), Chris E. Wagner (Rochester, NY)
Application Number: 11/584,026
International Classification: A61F 2/16 (20060101);