MXPA99002842A - Method and apparatus for inserting a flexible membrane into an eye - Google Patents

Abstract

This invention is an instrument (10) for inserting a flexible intraocular lens or other flexible membrane into an eye, which includes a compressor (26) for laterally compressing the lens into a small cross-sectional configuration to pass the lens through a narrow incision. The compressor includes retainers (68, 70) along the interior of the inserter to maintain the side edges of the lens in a substantially planar orientation during compression. The retainers preferably extend through the inserter to hold the lens during advancement toward the eye to prevent an uncontrolled rotation of the lens.

Description

METHOD AND APPARATUS FOR INTRODUCING A FLEXIBLE MEMBRANE IN AN EYE Field of the invention The present invention relates to a method and apparatus for introducing a flexible intraocular lens or other flexible membrane into an eye. BACKGROUND OF THE INVENTION The natural lens of the eye plays a primary role in the approach of light to the retina for correct vision. However, vision through the natural lens may deteriorate due to injury or because of the formation of a cataract caused by age or disease. To restore vision, the natural lens is typically replaced by an artificial lens. An artificial lens can also be implanted to effect a refractive correction. Many surgical procedures have been developed to extract the natural lens. Typically, a thin implement is inserted through a small incision in the eye to contact the natural lens. The implement includes a cutting tip that is vibrated ultrasonically to emulsify the lens. The emulsified fragments of the lens are aspirated from the eye through a passage provided in the cutting tip. The fine nature of the implement allows for the removal of the lens through a small incision in the eye. The use of a small incision compared to other procedures that require a large incision can reduce the trauma and complications that occur during surgery and postoperatively. Since the incision needed to remove the lens is small, the development of infra-ocular implants to replace the lens has occurred in the direction of flexible implants that do not require extending the incision. An infraocular lens usually includes a generally disk-shaped optic that focuses light on the retina and a haptic portion that extends outward for proper placement of the optic within the eye. The flexible nature of the lens allows the lens to be bent and compressed so that it occupies the smallest cross-sectional area for passage through the narrow incision and introduction into the eye. Once inserted through the incision, the lens can expand to its original size and shape. Several devices have been developed to introduce a flexible infra-ocular lens through a small incision in the eye. For example, U.S. Patent No. 4,681,102 to Bartell uses an articulated cartridge that closes around a lens to bend the lens to a narrower configuration. The cartridge is placed in an inserter mechanism that introduces the bent lens into the eye. However, the insertor requires the handling and assembly of several components during the operation. U.S. Patent No. 5,275,604 to Rheinish et al. Pushes the lens through a narrowing lumen, provided with slots which serve to bend the lens to a smaller size when it is pushed toward the eye. The manufacture of spiral grooves in a tapered lumen is difficult, if not impossible, to carry out in a practical manner. In U.S. Patent No. 5,304,182 issued to Rheinish et al., A shirring member is laterally displaced to bend the lens to a size small enough to pass through the narrow incision. However, no locking device is provided to guarantee complete closure of the shirring element. In addition, although these devices serve to reduce the cross-sectional size of the lens for insertion into the eye, they all require that the opposite lateral edges of the lens fold over on themselves to fit through the small incision. As a result, the lens must be opened inside the eye to recover its original shape and size. Such deployment causes the lens, and in particular the haptics, to tilt in an arc, and therefore runs the risk of damaging the interior of the eye. When the lens is released in the eye, the elasticity of the lens causes the lens to open and regain its natural shape. However, the folding and pressure of the lens, necessary to pass the lens through the small incision, imposes a considerable amount of inward pressure on the lens. As a result, the lens is frequently discharged from the inserter with considerable force and speed. Such forced, uncontrolled release of the lens also creates the risk of injury to the inside of the eye. In addition, many inserters do not maintain control of the orientation of the lens when the lens is inserted into the eye. Accordingly, the lens can rotate or rotate about a longitudinal axis when it is pushed through the inserter. However, most lenses are made to be placed in the eye in a specific orientation. Accordingly, such rotation of the lens can result in the lens being placed in the eye in an incorrect orientation. SUMMARY OF THE INVENTION The present invention relates to a method and apparatus for introducing a flexible intraocular lens or other flexible membrane into an eye without the aforementioned risks associated with the insertion devices of the past. More specifically, the inserter of the present invention maintains the substantially planar orientation of the opposite lateral edges of the lens when the lens is laterally compressed to a smaller cross-sectional configuration for introduction through a narrow incision in the eye. Since the lateral edges of the lens do not bend on themselves during compression, the lens does not tilt open in the eye in order to recover its original shape. As a result, the risk of a part of the lens colliding and injuring the inner portion of the eye after the release of the lens of the inserter is reduced. In the preferred construction, catches are formed in the form of channels along the interior of the inserter to receive and maintain the lateral edges of the lens in a substantially planar orientation during compression. The channels also extend through the inserter to maintain the lens during the advance toward the eye in order to prevent uncontrolled rotation of the lens. In this way, it is guaranteed that the lens is discharged in its proper orientation. In another aspect of the invention, the inserter allows the lens to expand before it is released to the eye. In this way, the elastic force that serves to expand the compressed lens dissipates before the lens is discharged from the inserter. The lens can thus be implanted in the eye in a controlled manner. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of an instrument according to the present invention. Figure 2 is a partial perspective view of the instrument with a compressor in a closed position.

Figure 3 is a partial perspective view of the instrument with the compressor removed. Figure 4 is a perspective view of the compressor.

Figure 5 is a partial perspective view of the instrument with an intraocular lens at the free end of the instrument. Figures 6A-6C are cross-sectional views of the instrument taken along line 6-6 of Figure 1 with the compressor in different stages of copying a lens. Figure 6D is a partial cross-sectional view of the instrument taken along line 6-6 of Figure 1 with the compressor in a closed position and the lens omitted. Figure 7 is a cross-sectional view taken along line 7-7 of Figure 1. Figure 8 is a partial cross-sectional view of a second embodiment of an instrument according to the present invention illustrating the compression of a lens Figure 9 is a partial perspective view of a third embodiment of an instrument according to the present invention.

Figure 10 is a partial top plan view of the third embodiment of the instrument. Figure 11 is a partial perspective view of a fourth embodiment of an instrument according to the present invention. Figure 12 is a partial perspective view of a fifth embodiment of an instrument according to the present invention. Figure 13 is a partial cross-sectional view of the fifth embodiment of the instrument.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to an inserter 10 (fi gures 1-7) for implanting a flexible intraocular lens or other flexible membrane in an eye. An intraocular lens typically includes an optic and a haptic portion, although the haptic portion is omitted occasionally. The haptic portion can assume many forms, but generally it is composed of plate or loop haptics. For purposes of illustration only, this application will describe the use of the inserter 10 with a lens 12 having a pair of loop haptics 16a, 16b (Figures 1, 5, 6, 8 and 10). However, the inserter 10 can be used with a wide variety of lenses or other flexible membranes. The lens 12 includes an optic 14 and a pair of loop haptics 16a, 16b (figures 1, 5, 6, 8 and 10). The haptics are thin, wire-shaped elastic elements that extend from diametrically opposite sides 18a, 18b of the optic 14 in opposite directions. The haptics 16a, 16b are arcuate in shape so that their free ends 20 point generally back towards the optic 14. In the preferred construction, the inserter 10 includes a tubular element 22 for receiving and directing the lens to the eye (FIGS. 3 and 5-7). The tubular element 22 generally includes a body 24, a compression station 26, and a cannula 28 (figures 1-3 and 5). The body 24, the cannula 28 and a support portion 29 of the compression station 26 are preferably formed as a unitary molded element, although an integral multi-part assembly may also be used. At the proximal end of the element 22, the body 24 forms a backward opening passage, which is adapted to receive a plunger 32 (Figure 1). The plunger includes a base 34 received with coupling in the body 24 and a shaft 36 (Figure 10) extending forward to engage and push the lens 12 to the eye. As is known in the industry, the base of the plunger 32 is configured to prevent rotation of the plunger relative to the tubular element 22. For example, the base 34 and the passage may have complementary non-circular shapes or a key construction and keyway. Further, although the plunger 32 is preferably advanced manually through the body 24, a motor or other drive assembly could be used to move the plunger. The compression station 26 includes a hole 38 in axial alignment with the passage of the body 24 for receiving, compressing and directing the lens 12 to the cannula 28 (Figures 1-6D). The compression station 26 includes a support 29 molded with the body 24 and a cannula 28, and a compressor 40 which is mounted to move in the holder. The support 29 includes a generally U-shaped wing 42 provided with an elongated ledge 44 and a pair of arms 46. The arms and the shelf together define a lateral channel or guide 48 in which the compressor 40 is received in a mobile manner. . A lip 50 formed along the free end of each arm 46 retains the compressor 40 against the shelf 44 and thereby restricts the compressor to a lateral movement in the channel 48. The inner end of each lip 50 defines a projection 55 on which is received a detent 56 of the compressor 40 to lock the compressor in position for operation. An additional stop tab (not shown) or other known construction may also be included to prevent the compressor 40 from leaving the channel 48. The compressor 40 includes a pair of side faces 61 that are adapted to be received with coupling within the channel 48. , and an inner side wall 62 which is adapted to engage and compress the lens 12. A cover flange 64 protrudes beyond the side wall 62 to cover the opposite side 58 of the support 29 and close the hole 38 when the compressor is displaced inwards (figures 2 and 5-6D). The detents 56 are positioned along each side of the compressor 40 above the cover flange 64. The detents 56 have ramps 65 that facilitate movement inward of the compressor, and abutment faces 68 that jump to engage the projections 55. and locking the compressor 40 in its closed position with the support 29. The compressor is preferably irreversibly locked in position for a single use, but could be constructed to allow release if desired. The flanges 70 are below the lips 50 to guide the lateral movement of the compressor 40 within the channel 48 (Figures 1 and 4). The compressor 40 can be moved to the sides between an open position where the cover flange 64 is spaced from the side 58 of the support 29 (figure 1), and a closed position where the cover flange 60 covers the side 58 and the retainers 56 the projections 55 engage (figures 2, 5, 6C and 6D). In the open position, an interval 66 is defined between the cover tab 64 and the side 58 for placing a lens 22 in the hole 38 (figure 1). The lens can be placed inside the tubular element 22 before shipment or by medical personnel at the time of performing the surgery. In the closed position, the side wall 62 of the compressor 40 is positioned in opposite relation to a side wall 60 on the side 58, and in axial alignment with the inner ends 52 of the arms 46 (Figures 2, 5, 6C and 6D). Each side wall 60, 62 is provided with a detent that receives and retains the opposite lateral edges 18a, 18b of the optic 14 to prevent the side edges from folding or turning when the compressor 40 moves to its closed position (FIGS. 4 and 6A-6D). More specifically, the lateral edges 18a, 18b of the lens are oriented generally along a central plane. The detents serve to retain and support the lateral edges of the lens in said generally flat relationship during compression of the lens. Since the lateral edges of the lens are not folded on themselves, the lens expands laterally within the eye without oscillating movement. Said lateral displacement of the lateral edges for the expansion of the lens is safer and less likely to contact and deteriorate the interior of the eye than an oscillating movement to deploy the lens. In the preferred construction, the detents are formed as channels 68, 70. However, the detents could have other constructions provided they keep the sides of the lens in substantially flat orientation and allow the lens to advance to the eye. The channels 68, 70 are preferably flanked by inclined segments 72-75 which support and compress the optic during inward movement of the compressor 40., and which contribute to maintaining the sides of the lens 12 in the channels 68, 70 (FIGS. 6A-6D). The side walls 60, 62 are spaced apart by upper and lower parallel surfaces defined by the cover flange 64 and the shelf 44 to form an axial passage 76 through which the lens is advanced with the plunger 32. When the compressor 40 is Inwardly displaced, the lateral edges 18a, 18b of the optic 14 are received within the channels 68, 70 (Figure 6A). The continued movement inward of the compressor causes the sides 18a, 18b to be pushed tightly into the channels 68, 70 in order to prevent their release (Figure 6B). This movement of the compressor 40 also begins to laterally compress the lens. Although the lens will tend to contract slightly during compression, the side edges 18a, 18b of the lens are retained in channels 68, 70 to maintain the edges 18a, 18b in generally planar relationship. Finally, when the detents 56 are locked in the projections 55, the lens 12 is in a compressed configuration between the side walls 60, 62 (FIG. 6C). The inner ends 52 of the arms 46 (FIG. 3) are also provided with surfaces that are identical to the side wall 62 to form continuous walls for the passage 76 (FIG. 6D).

Although flank segments 72-75 can be identical mirror images of each other (see channels 68a, 70a and segments 72a-75a of Figure 8), they are preferably asymmetric to better target the haptic for introduction (Figure 6D). More specifically, each of the channels 68, 70 is partially defined by upper and lower faces 80-83. A face 80, 83 of each channel 68, 70 extends inward a greater distance than the opposite face 81, 82. The longer faces 80, 83 join with arcuate flank segments 72, 75. The shorter faces 81, 82 terminate and intersect the flank segments 73, 74 at points closest to the outer faces 92, 94 of the channels 68, 70. Although the intersections of the faces 81, 82 with the flank segments 73, 74 are preferably angular, they can also be rounded. In this particular construction, the side edge 18a with the front haptic 16a is positioned adjacent the side wall 60. When the compressor 40 moves inward, the side edges 18a, 18b will be received in the channels 68, 70 (FIGS. 6A- 6D). When the lens 12 is compressed, the asymmetric faces 80-83 will cause the lens to sink slightly around the shorter faces 81, 82, and create a slight twist in the optic 14 so that the front haptic 16a tends to point at direction down. Said downward orientation of the front haptic 16a will allow the surgeon to more easily place the haptic within the capsular bag of the eye. Likewise, the rear haptic 16b moves to tilt slightly upwards to avoid contact with the plunger 32, that is, so that the free end 77 of the shaft 36 directly engages the optic 14 (FIG. 10). Alternatively, the compression station 26b includes a support 29b molded with the body 24b and a cannula 28b, and a pair of opposed compressors 40b, 41b (figures 9 and 10). The compressors are supported in a pair of opposed slits 96b formed on the sides of the support 29b to approach and move away from each other. The compressors 40b, 41b have inner side walls 60b, 62b which are preferably configured as described above with respect to the side walls 60, 62; however, the side walls could be formed symmetrically as with side walls 60a, 62a. A hole 66b is formed in the upper part of the support 29b to allow the placement of a lens 12. To prevent the loss or bending-out of the lens, a cover 101b is hinged in the support 29b to cover the hole 66b before closing the compressors 40b, 41b. Checks (not shown) are planned to block the compressors in their closed positions. The cannula 28 protrudes forward from the distal end of the compression station 26 to direct the lens 12 to the eye (Figures 1-3 and 5). The cannula 28 preferably includes a funnel-shaped proximal portion 103 that tapers to further compress the lens, and an elongated distal portion 105 that directs the lens compressed to an eye. However, the cannula could be formed so as to have a uniform taper across its length or not be provided with taper if, for example, the compressor (s) has a longer stroke for complete the desired compression of the lens. An outer lumen 107, extending through the cannula 28, is axially aligned with the passage 76 of the compression station 26 to form a continuous passage through which the lens 12 moves (Figure 7). The lumen 107 is preferably defined by side walls 109 provided with channels 111 and upper and lower flank segments 113, 115 so as to coincide with the side walls 60, 62 of the compression station 26. At the rear end 117 of the portion next 103, the channels 111 are aligned with the channels 68, 70 (when the compressor 40 is in the closed position) to form a continuous retention of lateral edges 18a, 18b when the lens is inserted in the eye. The side walls 109 of the proximal portion 103 converge preferably forward at an angle of approximately 7o to further compress the lens as it passes through the cannula 28. As indicated above, the channels 111 continue to hold the side edges 18a, 18b of the optic 14 when the lens passes through the cannula 28 to maintain the generally flat orientation of the lateral edge of the lens and prevent rotation of the lens during its advance through the lumen 107. The distal portion 105 of the cannula 28 is a elongated thin tube to allow entry of the inserter 10 through a narrow incision (not shown). Although the side walls 109 in the distal portion 105 are angularly oriented to the side walls 109 in the proximal portion 103, they are identical with respect to the formation of the channels 111 and the flank segments 113, 115. Accordingly, the channels and the flank segments continue through the distal portion 105 to suitably support and hold the lens 12 during its passage through the cannula 28. Although the side walls 109 at the distal portion 105 preferably converge slightly for molding purposes, they could be formed with parallel walls. The free end 119 of the cannula 28 is preferably provided with a pair of opposed longitudinal slots 121 in the channels 111 (Figures 1-3, 5 and 7). The slits 121 are wide enough so that the sides 18a, 18b of the optic 14 extend outwardly beyond the outer sides 123 of the cannula 28. Therefore, the slits allow the lateral expansion of the lens prior to its discharge into the lens. the eye. As a result, the natural elastic force that pushes the lens to assume its original uncompressed shape dissipates in the controlled environment of the cannula. Thus, the lens is not released with speed as in many inserts of the prior art. Furthermore, since the lens is compressed without folding the side edges on themselves, the expansion of the lens requires only a lateral movement outwardly of the lens. The lens does not experience tilting of the optician or the haptics inside the eye, which runs the risk of damaging the interior of the eye. The slits 121 also continue to hold the optic 14 and prevent rotation of the lens so as to ensure lens implantation in the proper orientation. Accordingly, the insertion of the lens with the inserter 10 provides a safer implantation procedure than previously performed. A haptic guide 125 is optionally provided in the front of the inserter 10b (or 10) to ensure proper positioning of the front loop haptics 16a (see Figures 9 and 10). The haptic guide 125 includes a generally planar pull tab 127 and a thin rod 129 projecting from the pull tab. The rod 129 is dimensioned such that it is received rearwardly within the lumen 107 from the free end 119. A hook 131 or other protruding element is formed on the free end 133 of the rod 129. In practice, the rod 129 is fully inserted. in the lumen 107 so that the hook 131 is visible through the interval 66b in the compression station 26b. When the lens is loaded into the hole, the front haptic 16a forms a loop on the hook 131. Manually pulls forward the pull tab 127 to pull the rod 129 out of the inserter 10. The removal of the haptic guide 125 is it can be performed before or after closing the compressors 40b, 41b or the cover 101b. When the rod is moved forward, the hook 131 engages and pulls the haptic 16a forward so that its free end is placed in the lumen 107. This traction of the haptic tends to partially straighten the haptic 16a so that it points generally at the direction of movement of the lens. This placement of the haptic reduces the risk of the front haptics 16a being pulled back and being housed around the optic during insertion. Preferably, ribs 135 or other grip surface are formed on the pull tab 127 to improve manual grip. of the component. As is common with lens insertion procedures, a viscoelastic or other lubricant material is injected into the inserter to facilitate the introduction of the lens into the eye. The lubricant can be injected before the closure of the compressor 40 (or the cover 101b). Alternatively, the cover flange 64c (or a wall of the tubular element) may be provided with a hole 137 through which the lubricant may be injected after closing the compressor 40c (Figure 11). In addition, a lubricant bag 139 filled with lubricant 141 can be attached to the exterior of the cover flange 64d (Figures 12 and 13). A burr may be provided adjacent the hole to pierce the plastic bag in order to allow the lubricant to be released to the passage after applying pressure to the bag. Alternatively, the bag 139 includes a frangible portion (eg, by streak) which is aligned with a small hole 143 in the cover flange 64. Once the compressor is moved to its closed position, the user can apply pressure to the lubricant bag 139 to open the bag and dispense the lubricant into the hole 38 through the hole 143. In addition, the cover flange 64c can cooperate with a fixed blade (not shown) to open the bag 139 when closing the compressor 40c to allow the discharge of the lubricant through the hole 143 and the passage. The above explanation refers to the preferred embodiments of the present invention. Various other embodiments as well as many changes and alterations can be made without departing from the spirit and broader aspects of the invention defined in the claims. For example, the compression station, with or without the cannula, can be formed as a removable cartridge to compress the lens. The cartridge can then be placed inside an injector device to introduce the lens into the eye after the lens has been compressed. As is common with the cartridges, one could include tabs or other structures to facilitate the handling of the cartridge and avoid the rotation of the cartridge in the injector device. In addition, the central portion of the optic 14 could be manipulated to a U-shape, shape or other folded configuration as opposed to direct compression of the preferred embodiment. Provided that the lateral edges of the lens are maintained in a generally flat orientation, the lens will still expand with a lateral displacement movement that prevents large tilting of the outer edges and haptics within the eye.

Claims (45)

1. An instrument for introducing a flexible membrane into an eye, said instrument including a tubular element defining a passage through which a flexible membrane is directed to an eye, a compressor for laterally compressing the flexible membrane, and seals to maintain the opposite lateral edges of the flexible membrane in a generally flat relationship during compression.

An instrument according to claim 1, further including a plunger for advancing the flexible membrane through said passage and inserting it into the eye.

3. An instrument according to claim 1, wherein said step includes a pair of sides, and wherein said compressor defines a side.

4. An instrument according to claim 1, wherein each said retainer includes a channel adapted to receive a lateral edge of the flexible membrane.

5. An instrument according to claim 4, wherein said channel is flanked by inclined segments.

An instrument according to claim 4, wherein each said channel includes a pair of substantially parallel, opposite wall segments, where one of said opposite wall segments of each channel enters said hole a greater distance than said other segment of wall. opposite wall.

An instrument according to claim 6, wherein said opposite wall segments are on first and second sides of a transverse axis of said passage, the longest of the wall segments for a channel is on the first side of the transverse axis and the longest of the wall segments of the other channel is on the second side of the transverse axis.

An instrument according to claim 1, wherein each said retainer extends longitudinally substantially along the entire passage to prevent uncontrolled rotation of the flexible membrane during the advance through said passage.

9. An instrument according to claim 8, wherein each said retainer includes a channel adapted to receive a side edge of the flexible membrane.

An instrument according to claim 1, wherein the distal ends of said detents are each provided with a slit through which the flexible membrane can be expanded prior to discharge of the flexible membrane from said passage.

An instrument according to claim 1, wherein said tubular element includes a guide for directing the movement of said compressor in a lateral direction.

An instrument according to claim 1, wherein said tubular element includes a hole for introducing a flexible membrane in said passage, and said compressor includes a flange that closes said hole when the flexible membrane is compressed.

An instrument according to claim 1, further including a bag filled with lubricant and a hole through which the lubricant can be dispensed from the bag and at said passage.

14. An instrument according to claim 1, further including a second compressor diametrically opposite said first compressor.

15. An instrument according to claim 14, wherein each said compressor includes a retainer.

16. An instrument according to claim 15, wherein said detents include channels adapted to receive the lateral edges of the flexible membrane.

17. An instrument according to claim 16, wherein each of said channels is flanked by inclined segments.

18. An instrument according to claim 1, wherein the flexible membrane is a lens with an optical, a front loop haptic and a back loop haptic, and the instrument further includes a haptic guide that can be moved in said step to straighten partially the front haptic in the forward direction of the lens.

19. An instrument according to claim 18, wherein said haptic guide includes a rod with a free end and a projection on said free end for engaging and pulling the front haptic in said step.

20. An instrument according to claim 19, wherein said haptic guide further includes a pull tab for manually grasping and pulling said haptic guide from said step.

21. An instrument for introducing a flexible membrane into an eye, said instrument including a tubular element defining a passage for receiving a flexible membrane, said flexible element having opposite side edges aligned along a transverse axis of said eye. step, said step defining a path through which the flexible membrane is directed to an eye, a compressor movably mounted on said tubular element to laterally compress the flexible membrane in said passage, and seals in said passage to retain the lateral edges of the flexible membrane in general along said transverse axis during compression.

22. An instrument according to claim 21, further including a plunger for advancing the flexible membrane through said passage and inserting it into the eye.

23. An instrument according to claim 21, wherein said detents extend longitudinally along said passage to prevent uncontrolled rotation of said flexible membrane during advancement by said plunger.

24. An instrument according to claim 21, wherein each said retainer includes a channel for receiving a side edge of the flexible membrane.

25. An instrument according to claim 21, including a second compressor movably mounted on said tubular element for laterally compressing the flexible membrane in said passage, wherein said compressors are diametrically opposed to each other.

26. An instrument according to claim 25, wherein each compressor includes a retainer.

27. An instrument according to claim 26, wherein each retainer includes a channel for receiving a lateral edge of the flexible membrane.

28. An instrument for introducing a flexible membrane for introduction into an eye, said instrument including a pair of sides that can be moved relative to one another between an open position and a closed position, said sides being placed one relative to another in the open position to allow the placement of a flexible membrane in the instrument, said sides being placed one in relation to another in said closed position to laterally compress the flexible membrane between the sides and define a passage for directing the flexible membrane towards an eye, each side including a retainer for contacting opposite side edges of the flexible membrane and maintaining the side edges in a generally flat relation to each other.

29. An instrument according to claim 28, wherein each said retainer includes a channel adapted to receive a lateral edge of the lens.

30. An instrument according to claim 29, wherein each mentioned channel is flanked by inclined wall segments.

31. An instrument according to claim 29, wherein each said channel includes a pair of substantially parallel, opposite wall segments, wherein one of said opposite wall segments of each channel enters said passage a greater distance than said other segment of wall. opposite wall.

32. An instrument according to claim 28, wherein at least one of said sides is defined by a compressor that can move laterally between the open position and the closed position.

33. An instrument according to claim 28, wherein each said side is defined by a compressor that can move laterally between the open position and the closed position, where said compressors are diametrically opposed to each other.

34. An instrument for introducing a flexible membrane into an eye, said instrument including a tubular unit including a passage through which a flexible membrane is directed to an eye, a hole extending through a wall of said eye. tubular unit, and a bag filled with lubricant, the lubricant being selectively dispensable from said bag through said hole and said passage.

35. An instrument according to claim 34, further comprising a plunger for advancing the flexible membrane through said passage and to the eye.

36. An instrument according to claim 34, wherein said bag includes a portion in alignment with said hole, wherein said portion breaks open by applying pressure on said bag.

37. An instrument for introducing a lens into an eye, including an optical lens, a front loop haptic and a back loop haptic, said instrument including a tubular unit including a passage through which the lens is directed to the eye , and a haptic guide that can be moved in said step to partially straighten the front haptic in the forward direction of the lens.

38. An instrument according to claim 37, wherein said haptic guide includes a rod with a free end and a projection on said free end for engaging and pulling the front haptic in said step.

39. An instrument according to claim 38, wherein said haptic guide further includes a pull tab for manually grasping and pulling said haptic guide from said passage.

40. An instrument for introducing a flexible membrane into an eye, said instrument including a tubular unit including a passage through which a flexible membrane is directed to an eye, a compressor for compressing the flexible element to introduce it through a small incision in the eye, a plunger for moving the flexible membrane through said passage, and means for the flexible membrane to expand to a substantially uncompressed condition prior to discharge of the flexible membrane from said passage.

41. An instrument according to claim 40, wherein said means for allowing expansion includes a plurality of slits in the distal end of the tubular unit.

42. A method of implanting a flexible membrane in an eye through an incision, said method including: placing a flexible membrane in an inserter; laterally compressing the flexible membrane in such a way that the opposite lateral edges of the flexible membrane approximate one another generally along a plane; and moving the lens from said inserter to an eye such that the flexible membrane is compressed as it passes through the incision in the eye.

43. A method according to claim 42, wherein the inserter includes a pair of opposing sides that can be moved relative to each other between an open position for said positioning of the flexible membrane in the inserter and a closed position to compress the flexible membrane .

44. A method according to claim 42, wherein the flexible membrane is inserted into the eye without rotating with respect to the inserter.

45. A method according to claim 42, further including expanding the lens after it has passed through the incision, and retaining the flexible membrane partially within the inserter when the flexible membrane is expanded to prevent uncontrolled release of the flexible membrane of the flexible membrane. insertor