Abstract:
An injector and method for injecting a dual optic AIOL into an eye wherein the AIOL is loaded into the injector in an initially loaded condition with the first and second optics in generally coaxial alignment. A lens moving element is provided and operable to move the first optic toward the proximal end of the main body whereupon the first optic becomes located proximally of the second optic. A stop may be provided to prevent the second optic from moving proximally with the first optic. Displacing the optics to a non-coaxial position reduces the cross-sectional area of the AIOL which allows the AIOL to non-destructively compress to the size of the opening of the injector tip which may be as small as about 2.8 mm or less, for example.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention generally relates to intraocular lens (“IOL”) injectors, and more particularly relates to an injector and method for facilitating injection of an accommodating intraocular lens (hereinafter “AIOL”) having two lenses into an eye. 
         [0002]    AIOLs having two optics interconnected by one or more flexible haptics are known, an example of which may be seen in  FIG. 1  hereof. While dual optic AIOLs are relatively new, single optic IOLs have been around for decades. Most of the IOL injector art has therefore been developed around the single optic IOL. A common injector design for delivering a single optic IOL into an eye includes a main body having a lumen extending between distal and proximal ends of the main body. A plunger is received at the proximal end of the body and telescopes within the lumen in the manner of a syringe. A tip is provided at the distal end of the injector body and gradually tapers to an opening wherethrough the IOL is expressed from the injector. A single optic IOL is placed inside the lumen and the plunger is advanced to engage and push the IOL through and out the tip. The IOL is made of a material allowing the IOL to compress as it is advanced through the narrowing walls of the tip. As such, the tip opening may be made very small, e.g., about 3 mm or less, which in turn allows for entry of the tip through a smaller incision in the eye. A sub 3 mm incision allows for faster recovery and has become the standard in the cataract surgery field. 
         [0003]    AIOLs having two optics generally cannot be used in injectors that have been designed for single optic IOLs described above. IOL injectors are designed to control the interface between the IOL and the plunger. Absent such control, the delicate IOL would likely be damaged during delivery through the injector and rendered useless. Thus, injectors designed for single optic IOLs would probably damage a dual optic AIOL since such an injector would not have precise control over the optic/plunger interface. Injectors specifically designed for dual optic IOLs may be seen in published patent application US 2005/0182419 A1 to George Tsai, published Aug. 18, 2005, and US 2004/0160575 A1 to Ian Ayton et al, published Aug. 19, 2004. 
         [0004]    In the Tsai application, an injector is provided having a main body with a plunger and an actuator  104  having a pair of pins  106 ,  108  which engage the bottom optic. The actuator is manually telescoped along the main body which causes the bottom optic to advance within the lumen of the main body while the upper optic trails along behind the bottom optic. Further advancement of the actuator urge a pair of compacting members  130 ,  132  forward along with the IOL and actuator. The compacting members also move toward each other to compact, crush and/or fold the IOL. The actuator may then be removed and discarded from the injector main body (see paragraph [0039] thereof) and a plunger is advanced to express the IOL from the injector tip. In another embodiment seen in  FIGS. 13-15  thereof, the actuator is in the form of a polymer strip which pulls the bottom optic forward due to the frictional engagement therebetween. In each embodiment, as the first optic is moved forward, the second optic engages an inclined portion of the housing which forces the first optic rearward and downward relative to the advancing second optic. As such, the optics become displaced relative to each other in a flatter, non-coaxial arrangement (see paragraphs [0035] and [0036] thereof). 
         [0005]    In the Ayton et al application, the injector includes a pair of opposing engagement faces  212 ,  242  which are generally flat and constructed from a material to which the outer faces of the viewing elements  122 ,  124  will self-adhere. The upper engagement surface is advanced forward and downward to pull the optic therealong and displace one optic relative to the other optic. The upper lens compactor having engagement surface  242  is then advanced laterally to “crush” the IOL into a second compacted condition shown in  FIG. 18  thereof. 
         [0006]    In both the Tsai and Ayton et al publications, one of the optics is engaged and moved in a distal direction toward the tip of the injector to relatively displace the optics. The injectors have many parts to execute the movement necessary to first displace the optics to a non-coaxial position, and then compact the optics for subsequent delivery through the injector tip. The number of parts required for the Tsai and Ayton et al injectors greatly increases the complexity of manufacture and assembly of the injector which adds to the cost thereof. Furthermore, each injector requires at least two separate manipulations to first displace and then compact the optics prior to advancement by the plunger. The more injector manipulations required, the more time needed for the IOL implantation procedure which decreases the efficiency of the procedure. 
         [0007]    There thus still exists a need for an dual optic AIOL injector that is relatively easy to manufacture, assemble and use. One or more embodiments of the present invention addresses these and other needs. 
       SUMMARY OF THE INVENTION 
       [0008]    In one embodiment, the present invention provides an injector for delivering a dual optic AIOL into an eye. The injector includes a main body having a lumen extending between proximal and distal ends. A tip is provided at the distal end and includes a lumen terminating at an opening wherethrough the AIOL is expressed from the injector and into an eye. A plunger is inserted into the proximal end of the main body and telescopes within the lumen in the manner of a syringe. The AIOL is loaded into the lumen in an initially loaded condition wherein the first and second optics are generally in coaxial alignment. An optic displacing element is provided and operable to move the first optic toward the proximal end of the main body whereupon the first optic becomes located proximally of the second optic. A stop may be provided to prevent the second optic from moving proximally with the first optic. Displacing the optics to a non-coaxial condition reduces the cross-sectional area of the AIOL which allows the AIOL to non-destructively compress to the size of the opening of the injector tip which may be as small as about 2.8 mm or less, for example. 
         [0009]    The tip may be a separate component which is attachable to the distal end of the main body. The distal end of the injector main body lumen may include a lens mounting surface adapted for placement of the AIOL thereon in the initially loaded condition. A cover may be provided movable between open and closed positions relative to the lens mounting surface. In the open position of the cover, the lens mounting surface is accessible for placing the AIOL thereon. The cover may then be closed and the tip may be attached to the distal end of the injector main body. The lens moving element may be formed as a projection within the tip lumen and positioned to move the first optic in a proximal direction as the tip is attached to the distal end of the injector main body portion. 
         [0010]    A ramp may be provided proximally of the lens mounting surface. As the first optic is moved proximally by the lens moving element, the first optic moves along the ramp, coming to rest proximally of the second optic which is considered the delivery condition of the AIOL. 
         [0011]    Once the AIOL has been moved from the initially loaded condition to the delivery condition, the plunger may be advanced toward the distal end of the main body portion whereupon it moves the first optic which in turn moves the second optic toward the tip. The distal end of the main body lumen and/or the tip lumen taper inwardly causing the first and second optics to compress as the AIOL is advanced and expressed from the tip. 
         [0012]    In another embodiment, the invention provides a method of preparing an intraocular lens having first and second optics for injection into an eye, the method comprising the steps of providing an injector main body portion having proximal and distal ends and a lens mounting surface, loading said intraocular lens onto said lens mounting surface; and moving the first optic toward the injector main body potion proximal end whereby said first optic becomes positioned proximally of said second optic. 
         [0013]    The method may further include the step of providing an injector tip having a lumen wherethrough said intraocular lens may travel and be expressed from said injector tip; providing a lens moving element on said injector tip, and attaching said injector tip to said lens mounting surface and thereby causing said lens moving element to move said first optic toward said injector body proximal end. 
         [0014]    The method may alternately include the step of providing the lens moving element on said lens mounting surface, and attaching said injector tip to said lens mounting surface and thereby causing said lens moving element to move said first optic toward said injector body proximal end. 
         [0015]    The method may further comprise the steps of providing a plunger within said injector body, and advancing said plunger toward said injector body distal end, said plunger operable to push and express said intraocular lens out of said injector tip. 
         [0016]    The method may further comprise the steps of providing a ramp proximally of said lens mounting surface, said lens moving element operable to move said first optic up said ramp. 
         [0017]    The method may further include the step of providing a stop to prevent the second optic from moving proximally with the first optic. 
         [0018]    The present invention, including its one or more embodiments, can be better understood with reference to the following drawings, detailed description and examples, which are included to teach the invention without limiting the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a perspective view of a prior art AIOL; 
           [0020]      FIG. 2  is a perspective view of an intraocular lens injector according to an embodiment of the invention; 
           [0021]      FIG. 3  is an enlarged, fragmented, perspective view of the tip and distal end of the injector main body portion of one embodiment of the invention; 
           [0022]      FIG. 4A-C  are fragmented, cross-sectional views of the distal end of the injector main body and tip showing the sequential steps of attaching the tip to the distal end of the injector main body portion of the injector of  FIG. 2 ; and 
           [0023]      FIG. 5  is an enlarged, fragmented, perspective view of the tip and distal end of the injector main body portion of another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    A prior art AIOL  10  is shown in  FIG. 1  and includes first and second optics  12 ,  14 , respectively, interconnected by three flexible haptics  16   a, b  and  c . As is well known in the intraocular lens art, AIOL  10  may be made of a hydrophilic or hydrophobic material which may be folded and compressed to deliver the AIOL through the small tip opening of the injector as explained below. 
         [0025]    An injector  18  according to an embodiment of the invention is seen in  FIG. 2  to include main body portion  20  having a lumen  22  (see  FIGS. 4A-C ) extending between proximal and distal ends  24 ,  26  thereof, respectively. A plunger  28  is received in lumen  22  at proximal end  24  of main body portion  20  and operates in the manner of a syringe to express the AIOL  10  from injector tip  30  and into an eye. 
         [0026]    Referring to  FIG. 3 , an embodiment of the invention is seen to include a lens platform  32  extending from main body portion distal end  26 . Lens platform  32  includes a lens mounting surface  34  adapted for placing the AIOL  10  thereon in an initially loaded condition seen in  FIG. 4A , i.e., lens mounting surface  34  is sized to allow placement of AIOL  10  thereon with first optic  12  and second optic  14  in spaced, generally coaxial alignment along an optical axis OA-OA which extends substantially perpendicular to the longitudinal axis X-X of injector  18  (see  FIG. 4A ). A cover  36  may be provided which is configured to close over lens platform  32  capturing AIOL  10  therebetween as seen in  FIG. 4A . Cover  36  may be pivotally connected to platform  32  via hinge connections  38 ,  40  (see  FIG. 3 ). 
         [0027]    A ramp  42  is provided on lens platform  32  proximally of lens mounting surface  34 . Ramp  42  includes an inclined surface which extends proximally and toward longitudinal axis X-X. 
         [0028]    In the embodiment of FIGS.  3  and  4 A-C, tip  30  is a separate component which is adapted to be connected to injector main body portion  20 . Tip  30  includes a lumen  44  extending between proximal and distal ends  46 ,  48 , respectively, with distal end  46  terminating in a small open tip  48   a  wherethrough the AIOL  10  is expressed from the injector  18  and into an eye. Proximal end  46  is shaped and sized to receive and encase lens platform  32  and cover  36  when in the closed position. 
         [0029]    A lens moving element  50  is provided within tip lumen  44  in the form of a finger-like projection extending toward proximal end  46 , terminating in a free end  52  which may be tapered. As seen in  FIG. 4A , lens moving element  50  is positioned to align with first optic  12  as platform  32  and cover  36  are located to be received in tip proximal end  46 . As seen in  FIG. 4B , as tip  30  is advanced further toward injector body distal end  26 , lens moving element free end  52  abuts first optic  12  and begins moving first optic  12  proximally up ramp  42 . Upon full advancement and attachment of tip  30  on lens platform  32  and cover  36 , first optic  12  becomes positioned at the top of ramp  42 . It will be noticed that as first optic  12  is moved proximally by lens moving element  50 , second optic  14  remains substantially stationary such that first optic  12  becomes positioned proximally of second optic  14  and thus no longer in coaxial alignment with first optic  12 , i.e., the optical axis OA of first optic  12  becomes off-set from the optical axis OA of second optic  14 . This is considered the delivery position in which the overall height and cross-section of AIOL is reduced to allow an optimum compression profile for expression from tip opening  48   a . It is noted that although first and second optics  12 ,  14  are shown in  FIG. 4C  as slightly overlapping, they may instead become positioned edge to edge or even slightly longitudinally spaced from each other. 
         [0030]    To ensure second optic  14  does not move proximally as first optic  12  is moved up ramp  42  by element  50 , a stop  54  may be provided in the form of a shoulder provided on the inner surface of cover  36  opposite lens mounting surface  34 . In the initially loaded condition of AIOL  10  and closing of cover  36 , stop  54  is positioned proximally of second optic  14 . As such, stop  54  forms a physical barrier against proximal advancement of second optic  14 . Other configurations and locations for stop  54  are of course possible to inhibit proximal advancement of second optic  14 . 
         [0031]    Once tip  30  has been fully attached to main body portion  20  as seen in  FIG. 4C , plunger  28  may be advanced within lumen  22  whereupon the plunger tip  28   a  engages and pushes against first optic  12 . Since second optic  14  is positioned distally of first optic  12 , both optics are advanced together toward and then expressed from open tip  48   a . Tip lumen  44  may taper toward open tip  48   a  to compress AIOL  10  to the size of open tip  48   a.    
         [0032]    As seen best in  FIG. 3 , ramp  42  may be provided in a bifurcated configuration with spaced ramp segments  42   a ,  42   b . The spacing between ramp segments  42   a ,  42  is such that first optic  12  will span and be supported by both ramp segments  42   a ,  42   b  as first optic  12  is moved up ramp  42  by lens moving element  50 . Lens moving element free end  52  may be positioned and configured to slide and fit between ramp segments  42   a ,  42   b  as tip  30  is attached to lens platform  32  and cover  36 . In this way, lens moving element  50  and ramp segments  42   a ,  42   b  form a support surface for first optic  12  when AIOL  10  is in the delivery position seen in  FIG. 4C . Upon advancing plunger  28 , AIOL is moved along the surface of lens moving element  50  which in part defines tip lumen  44 . 
         [0033]    In another embodiment of the invention shown in  FIG. 5 , the lens moving element is provided on the lens platform  32  in the form of a clip  150  which may slide therealong in the proximal direction as indicated by arrow “A”. A projection  152  connects to and moves together with clip  150  as indicated by arrow “B”. The proximal end  146  of tip  130  is shaped and sized to align with clip  150  such that as tip  130  is attached to lens platform  32 , proximal end  146  moves clip  150  (and hence also projection  152 ) toward main body portion  120 . Projection  152  is operable to move first optic  12  up ramp  142  in the same manner as lens moving element  50  in the embodiment of FIGS.  3  and  4 A-C. It is noted no cover similar to cover  36  is shown in  FIG. 5  for the sake of clarity. 
         [0034]    It will be appreciated that while the invention has been shown and described in relation to two possible embodiments thereof, many changes may be made without departing from the fill spirit and scope of the invention as defined by the claims which follow. For example, the injector tip  30  may be integrally formed with the main body portion of the injector rather than a separately attached component. In this instance, the lens moving element could comprise an element which extends radially through the injector body wall into the lumen. The element may be slidable within a groove provided in the injector body wall toward the proximal end of the injector body whereupon the element engages and moves the first optic proximally of the second optic. The ramp may be provided within the main body lumen proximally of the lens loading area. 
         [0035]    As a further example, the lens may be preloaded into the lumen at manufacture so that the doctor does not need to perform this step. 
         [0036]    As yet a further example, the lens may be preloaded into a cartridge which is adapted to be received in the injector body. The cartridge may include the lens moving feature such that the lens is moved to its delivery position prior to the cartridge being attached to the injector body. 
         [0037]    These and other modifications will be apparent to those skilled in the art.