Abstract:
Apparatus and method for preloading an intraocular lens ( 30, 30 ′) in a component of an injector device ( 10 ) and for reducing the force used to eject the intraocular lens ( 30, 30 ′) therefrom are disclosed. The intraocular lens ( 30, 30 ′) is positioned in a shuttle ( 16, 16 ′) which is positioned inside a distal section ( 14, 14 ′) of the device ( 10 ). The shuttle ( 16, 16 ′), IOL ( 30, 30 ′), and distal section ( 14, 14 ′) are positioned and sealed in a vial ( 11 ) of solution that comprises a surfactant. At the time of use, a user opens the vial ( 11 ) and attaches a proximal section ( 12 ) having a plunger ( 20 ) to the distal section ( 14, 14 ′) located in the vial ( 11 ). The proximal section ( 12 ) is then lifted away from the vial ( 11 ) together with the distal section ( 14, 14 ′), and the shuttle ( 16, 16 ′) and IOL ( 30, 30 ′) located in the distal section ( 14, 14 ′). The plunger ( 20 ) is advanced to express the IOL ( 30, 30 ′) from the distal tip ( 14   c,    14   c ′) of the distal section ( 14, 14 ′).

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to ophthalmic surgical devices and methods. More particularly, the present invention relates to a device and method for inserting an intraocular lens (IOL) into an eye, wherein the IOL may be conveniently preloaded in and packaged together with the injector device.  
         [0002]     IOLs are artificial lenses used to replace the natural crystalline lens of the eye when the natural lens has cataracts or is otherwise diseased. IOLs are also sometimes implanted into an eye to correct refractive errors of the eye in which case the natural lens may remain in the eye together with the implanted IOL. The IOL may be placed in either the posterior chamber or anterior chamber of the eye. IOLs come in a variety of configurations and materials. Some common IOL styles include the so-called open-looped haptics which include the three-piece type having an optic and two haptics attached to and extending from the optic; the one-piece type wherein the optic and haptics are integrally formed (e.g., by machining the optic and haptics together from a single block of material); and also the closed looped haptic IOLs. Yet a further style of IOL is called the plate haptic type wherein the haptics are configured as a flat plate extending from opposite sides of the optic. The IOL may be made from a variety of materials or combination of materials such as PMMA, silicone, hydrogels and silicone hydrogels, etc.  
         [0003]     Various instruments and methods for implanting the IOL in the eye are known. In one method, the surgeon simply uses surgical forceps having opposing blades which are used to grasp the IOL and insert it through the incision into the eye. While this method is still practiced today, more and more surgeons are using more sophisticated IOL injector (also called “inserter”) devices which offer advantages such as affording the surgeon more control when inserting the IOL into the eye. IOL injector devices have recently been developed with reduced diameter insertion tips which allow for a much smaller incision to be made in the cornea than is possible using forceps alone. Smaller incision sizes (e.g., less than about 3 mm) are preferred over larger incisions (e.g., about 3.2 to 5+mm) since smaller incisions have been attributed to reduced post-surgical healing time and complications such as induced astigmatism.  
         [0004]     Since IOLs are very small and delicate articles of manufacture, great care must be taken in their handling. In order for the IOL to fit through the smaller incisions, they need to be folded and/or compressed prior to entering the eye wherein they will assume their original unfolded/uncompressed shape. The IOL injector device must therefore be designed in such a way as to permit the easy passage of the IOL through the device and into the eye, yet at the same time not damage the delicate IOL in any way. Should the IOL be damaged during delivery into the eye, the surgeon will most likely need to extract the damaged IOL from the eye and replace it with a new IOL, a highly undesirable surgical outcome.  
         [0005]     Thus, as explained above, the IOL injector device must be designed to permit easy passage of the IOL therethrough. It is equally important that the IOL be expelled from the tip of the IOL injector device and into the eye in a predictable orientation and manner. Should the IOL be expelled from the tip too quickly or in the wrong orientation, the surgeon must further manipulate the IOL in the eye which could result in trauma to the surrounding tissues of the eye. Therefore, it is highly desirable to have an injector device which allows for precise loading of the IOL into the injector device and which will pass and expel the IOL from the injector device tip and into the eye in a controlled, predictable and repeatable manner.  
         [0006]     To ensure controlled expression of the IOL through the tip of the IOL injector device, the IOL must first be loaded into the IOL injector device. The loading of the IOL into the injector device is therefore a precise and very important step in the process. Incorrect loading of an IOL into the injector device is oftentimes cited as the reason for a failed IOL delivery sequence. Many IOL injector devices on the market today require the IOL to be loaded into the injector at the time of surgery by the attending nurse and/or surgeon. Due to the delicate nature of the IOL, there is a risk that the nurse and/or surgeon will inadvertently damage the IOL and/or incorrectly load the IOL into the injector device resulting in a failed implantation. Direct handling and/or loading of the IOL into the injector by the nurse and/or surgeon is therefore undesirable. In addition, as explained above, as the incision size continues to decrease, it becomes very desirable that the IOL be easily expelled through a smaller injector tip.  
         [0007]     There remains a need for an IOL injector and method, which deliver the IOL substantially uninhibitedly through a small incision and which remove the need for direct handling of the IOL by the eye care provider.  
       SUMMARY OF THE INVENTION  
       [0008]     In a broad aspect of the invention, an injector device is provided having proximal and distal sections which are packaged separately and then assembled together at the time of surgery. The injector device provides an IOL preloaded in the distal section of the device, which is stored in a solution (such as a sterile saline solution or buffered solution) that comprises a surfactant. At the time of surgery, a user of the injector device, such as a nurse or a surgeon, simply opens the packages containing the distal and proximal sections and attaches the proximal and distal sections together. The injector device is then ready to deliver the IOL from the injector device and into an eye. No other injector components are required to ready the device for delivery of the IOL therethrough.  
         [0009]     In one aspect, an IOL is expelled more easily (such as with a smaller amount of force) or with a lower risk of being damaged from an injector device of the present invention than from other injector devices.  
         [0010]     At the injector device manufacturing site, an IOL is placed in the distal section of the device which is placed in a container (e.g., a vial) of hydrating solution, which comprises a surfactant, and sealed. Particularly, the distal section includes a shuttle component having an IOL loading area in which the IOL is placed, preferably in an unstressed condition, i.e., in a condition where at least the IOL optic is not compressed or folded. The shuttle and IOL are inserted into a nozzle section which includes a distal tip through which the IOL is ultimately expelled from the injector device. Each of the shuttle and nozzle includes a longitudinal passageway, which preferably lies along a common longitudinal axis when the shuttle and nozzle sections are assembled together. The assembled shuttle (with IOL placed therein) and nozzle section together comprise the distal section of the injector device which is placed in a vial of hydrating solution (e.g., buffered saline) that comprises a surfactant. The package or vial is then sealed and sterilized. The hydrating solution maintains the IOL in a hydrated state until it is ready for use in a surgical procedure, a necessary requirement for IOLs made of certain materials such as hydrogels.  
         [0011]     The proximal section of the injector device is provided in a separately sealed and sterilized package although the proximal section and package or vial containing the distal section may be provided in a single “kit” type of package if desired for the sake of convenience to the user. The proximal section of the injector device includes a tubular body having a longitudinal passageway extending between opposite, open ends thereof. A plunger component is inserted into the proximal open end of the tubular body and telescopes within the longitudinal passageway thereof. The plunger includes a finger press at the proximal end thereof for manually applying a force and advancing the plunger through the passageway, and a plunger tip at the opposite, distal end thereof for engaging and pushing the IOL through and out the distal tip of the nozzle section of the injector device.  
         [0012]     At the time of surgery, a user, such as a nurse or a surgeon, removes the outer packaging from the proximal section of the device and opens the package or vial containing the distal section of the device. The distal, open end of the proximal section is inserted into the open end of the package or vial with the proximal section being snapped onto the distal section of the injector device. With the proximal and distal sections thus attached together, the proximal section is lifted away from the package or vial and thereby also removing the distal section from the vial. The package or vial and hydrating solution may then be discarded or recycled. With the proximal and distal sections of the device attached together, the device is ready to be used to implant the IOL into a patient&#39;s eye. No further attachment or removal of injector component parts is necessary as is required in more complicated prior art devices.  
         [0013]     The injector device includes means for compressing or otherwise urging the IOL into a smaller cross-section for delivery through the injector. In one embodiment of the invention, the shuttle and nozzle passageways are configured with a narrowing taper towards the distal tip. The plunger is advanced at the proximal end of the injector device causing the distal tip of the plunger to engage the IOL optic. As the plunger is advanced further, the IOL is pushed through the narrowing passageway, thereby compressing the IOL into a smaller cross-section and finally exiting at the distal end of the injector body and expressed into the eye in the intended manner.  
         [0014]     The relative positioning of the IOL shuttle, the IOL and the injector device is such that upon attaching the proximal and distal sections of the injector device together, the IOL becomes preferentially positioned inside the injector device. The IOL thus becomes positioned in a particular orientation inside the injector device relative to the plunger tip. This IOL loaded position results in the leading haptic being correctly aligned in the shuttle, and the trailing haptic and optic aligning with the plunger tip so that upon advancement of the plunger, the plunger tip will engage the IOL optic in the intended manner without obstruction or jamming of the trailing haptic.  
         [0015]     Other features and advantages of the present invention will become apparent from the following detailed description and claims, and the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is an exploded, side elevational view of a first embodiment of the injector device showing main components of injector device.  
         [0017]      FIG. 2  is a perspective view of the fully assembled injector device of  FIG. 1  showing the IOL expressed from the distal tip thereof.  
         [0018]      FIG. 3   a  is an enlarged perspective view of the proximal section of the injector device of  FIGS. 1 and 2 .  
         [0019]      FIG. 3   b  is a side elevational view thereof.  
         [0020]      FIG. 3   c  is an end view thereof.  
         [0021]      FIG. 4   a  is a side elevational view of the plunger component of the injector device.  
         [0022]      FIG. 4   b  is a perspective view thereof.  
         [0023]      FIG. 5   a  is a perspective, top view of a first embodiment of the shuttle component of the injector device with IOL loading area in the open position and an IOL positioned therein.  
         [0024]      FIG. 5   b  is a perspective view of the shuttle component of  FIG. 5   a  with the IOL loading area shown in the closed position and the shuttle being rotated 180° from the position shown in  FIG. 5   a.    
         [0025]      FIG. 5   c  is a top plan view of the shuttle component of  FIGS. 5   a,b  with the IOL loading area in the open position.  
         [0026]      FIG. 5   d  is an end view of  FIG. 5   c  taken from the left side thereof.  
         [0027]      FIG. 6   a  is a perspective view of the distal section of the injector device of the previous Figures.  
         [0028]      FIG. 6   b  is a top plan view thereof.  
         [0029]      FIG. 6   c  is a side elevational thereof.  
         [0030]      FIG. 6   d  is an end view thereof.  
         [0031]      FIG. 7  is a perspective view of the distal section and shuttle component positioned in a first embodiment of the vial component of the invention.  
         [0032]      FIG. 8   a  is a side elevational view of the proximal section and plunger components of the injector device in the process of coupling to the distal section located in the vial.  
         [0033]      FIG. 8   b  is a perspective view thereof.  
         [0034]      FIG. 9   a  is a perspective view of a second embodiment of the shuttle component with the IOL loading area in the open position and another style of IOL positioned therein.  
         [0035]      FIG. 9   b  is the view of  FIG. 9   a  with the shuttle IOL loading area in the closed position.  
         [0036]      FIG. 9   c  is the view of  FIG. 9   b  with a second embodiment of the distal section of the device shown coupled to the shuttle; and  
         [0037]      FIG. 10  is a perspective view of the first embodiment of the distal section shown coupled to the first embodiment of the shuttle component.  
     
    
     DETAILED DESCRIPTION  
       [0038]     In a first, broad aspect, the invention comprises a preloaded injector device for injecting an IOL into an eye. The term “preloaded” as used herein means that a packaged component of the injector device includes an IOL positioned therein. Therefore, direct handling and loading of an IOL into the injector device is not necessary.  
         [0039]     Reference being made to  FIGS. 1, 2 ,  3   a ,  5   a , and  9   a , the injector device  10  includes a proximal section  12  and a distal section  14  which are packaged separately and then attached together at the time of surgery to ready the device for delivery of an IOL  30  or  30 ′ therethrough and into a patient&#39;s eye (see  FIGS. 2, 5   a  and  9   a ). The IOL  30  or  30 ′ is preloaded into the distal section  14  of the device, which is packaged in a hydrated state in a vial  11  containing a solution that comprises a surfactant to maintain the IOL in a hydrated state until the IOL  30 ,  30 ′ is ready for use in a surgical procedure. Examples of IOL materials which may require wet storage include acrylic polymers, such as a copolymer of 2-hydroxyethyl acrylate (HEMA) and methyl methacrylate (MMA).  
         [0040]     Suitable surfactants are non-ionic and ionic surfactants. Desirably, the surfactants are compatible with the IOL materials and non-toxic. Non-limiting examples of surfactants suitable for use in the present invention are amino acids (e.g., leucine), poly(amino acids), sorbitan esters (e.g., sorbitan laurate, sorbitan stearate, sorbitan oleate) and their polyoxyethylene derivatives (e.g., polyoxyethylene sorbitan monooleate or Polysorbate 80), polysiloxanes, alginic acid, polyoxyethylene alkylphenol (e.g., polyoxyethylene octylphenol commonly known as Triton X100™), polyethylene glycol (e.g., PEG 200, 400, 600), polyethylene glycol distearate, benzalkonium chloride, propylene glycol, and their derivatives or equivalents. The surfactant concentration in the solution can range from about 0.001% (by weight) to about 5% (by weight). In one embodiment, the surfactant concentration ranges from about 0.01% (by weight) to about 1% (by weight). In another embodiment, the surfactant concentration ranges from about 0.05% (by weight) to about 0.5% (by weight). Typically, the solutions are aqueous, such as saline solution or borate buffered solution.  
         [0041]     The proximal section  12  includes a longitudinal passageway  12   a  extending between the open proximal and distal ends  12   b ,  12   c  thereof, respectively. The passageway  12   a  may assume any desired cross-sectional shape such as a rounded rectangular shape as shown.  
         [0042]     The distal section  14  includes a longitudinal passageway  14   a  extending between the open proximal end  14   b  and open distal tip  14   c  thereof. The passageway  14   a  tapers inwardly toward distal tip  14   c  so that the IOL is gradually compressed to a very small cross-section as it exits the device at tip  14   c.    
         [0043]     A first embodiment of the shuttle component  16  is provided into which an IOL  30  is loaded and held in an uncompressed condition. This will be described in more detail below. Shuttle  16 , with an IOL  30  loaded therein, is positioned in distal section passageway  14   a . Shuttle  16  also includes a longitudinal passageway  16   a  extending between the open proximal end  16   b  and open distal end  16   c  thereof. When shuttle  16  is positioned in distal section  14 , it is preferred, though not necessary, that the longitudinal passageways  16   a ,  14   a  of each are aligned along the same axis X-X. When the proximal section  12  is attached to the distal section  14 , the longitudinal passageway  12   a  is aligned along the common axis X-X of the distal and shuttle passageways  14   a ,  16   a  ( FIG. 2 ).  
         [0044]     Reference being made again to proximal section  12 , as shown in  FIGS. 3   a - 3   c , a finger flange  17  may be formed at the proximal end  12   b  thereof for ease in operating the injector device in the manner of a syringe. Finger flange is preferably configured with a straight edge  17   a  as shown ( FIG. 3   a ) for resting device  10  on a flat surface.  
         [0045]     A plunger  20  having proximal and distal lengths  20   a,    20   b , respectively, a distal plunger tip  22 , and a thumb press  24  telescopes within the proximal section  12 . When the proximal and distal sections  12 ,  14  are attached together, the plunger  20  extends sequentially through proximal section passageway  12   a  and the shuttle passageway  16   a  so as to engage and push the IOL  30  through passageway  16   a  and out distal tip  14   c . Although the applicants do not wish to be bound by any particular theory, it is believed that the surfactant in the solution adsorbs at the internal surfaces of the shuttle passageway  16   a , distal section passageway  14   a , and the surface of IOL  30 . Adsorbed surfactant reduces the friction force between the internal surface of tip  14   c  and the surface of IOL  30 , allowing IOL  30  to be compressed easily through tip  14   c , and allowing a significant reduction in the force required to express IOL  30  through tip  14   c , thus avoiding possible damage thereto. The present invention can allow the incision size to be reduced below 2 mm. The IOL delivery sequence will be explained in more detail below.  
         [0046]     It is understood that the overall configuration of the injector body  12  may vary from that shown and described herein. It is furthermore understood that the components of the injector device may be made of any suitable material (e.g., polypropylene) and may be wholly or partly opaque, transparent or translucent to better visualize the IOL within the injector device and the IOL delivery sequence. In a preferred embodiment of the injector device, the components thereof are steam sterilized, requiring that the components are made from a material which can withstand the heat applied during steam sterilization. Examples of such materials include, but are not limited to, polypropylene, polycarbonate, polysulfone, polymers or copolymers comprising fluoroethylene or fluoropropylene, and polyoxymethylene (POM). Non-limiting suitable polymers and copolymers comprising fluoroethylene and/or fluoropropylene are polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-perfluorovinylether copolymer (PFA), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), and tetrafluoroethylene-perfluoro alkylvinyl ether copolymer (PFE). These polymers are commercially available.  
         [0047]     A first embodiment of shuttle  16  is used for holding an IOL  30  in the preloaded position. The shuttle  16 , with IOL  30  held thereby, is positioned in the distal section  14  through opening  14   a  thereof. As seen best in  FIGS. 5   a - d , shuttle  16  includes an IOL loading area  16   d  wherein the IOL  30  is positioned in an unstressed state. Loading area  16   d  is in open communication with longitudinal passageway  16   a  and is configured to position the IOL  30  along axis X-X in an unstressed state and may include one or more optic support elements  16   e,f  each having a radius or other feature for aligning the IOL optic  31  along passageway  16   a  (and hence also axis X-X) about the periphery  31   a  thereof. Alternatively or in addition to the optic support elements, one or more haptic support elements  16   g - j  are provided on shuttle  16 , each of which include a radius or other feature for aligning one or more haptics  30   b - e  which attach to and extend from the optic  31 . In this regard, it is understood that the two IOL configurations  30 ,  30 ′ shown and described herein is for discussion purposes only, and that the present invention is not to be limited thereby. The invention may be easily adapted to IOLs of any configuration and type (e.g., IOLs with plate, open or closed loop haptics, anterior chamber IOLs, posterior chamber IOLs, accommodating IOLs (including single and double lens types), etc.). The overall configuration of the IOL shuttle  16  and IOL loading area  16   a  may thus likewise vary so as to be cooperatively configured with and align the particular IOL style being used with the device. For ease of description, the first invention embodiment will be described with reference to IOL  30 . In all embodiments, the shuttle  16  holds at least the IOL optic  31  in the unstressed state. It is furthermore preferable that shuttle  16  hold the IOL haptics at the correct vault angle (i.e., the angle from which they normally extend from the IOL optic periphery). It is even furthermore preferable that, in the case of an IOL having open looped haptics, such as IOL  30 ′ seen in  FIG. 9   a , the haptic support elements maintain the looped haptics  30   b ′,  30   c ′ at the correct angle of curvature. In  FIGS. 5   a  and  9   a , it is seen that the haptic support elements constrain the haptics along the outer curved edges thereof. This ensures that the haptic curvature, which is designed and set at manufacture of the haptics, does not increase or bend out of specification during storage of the IOL and shuttle. The embodiment of  FIGS. 9   a - c  will be described more fully below.  
         [0048]     At manufacture, the IOL  30  is placed in the shuttle  16 . Positioning the IOL  30  in the shuttle  16  may be done by a worker using a pair of tweezers, for example, although other methods may be used as desired, including automated or semi-automated means in an assembly line. To facilitate loading of the IOL in the shuttle, the IOL loading area  16   a  may be formed with two wall sections  16   k  and  16   l  which are pivotally connected (e.g., via a living hinge  16   m ) to enable opening and closing of the IOL loading area  16   d . Wall sections  16   k  and  16   l  are spread open in a coplanar relationship in the open position of the shuttle loading area  16   d . In this open position, IOL loading area  16   d  is easily accessible and an IOL  30  may be simply placed upon one of the two sections, preferably upon section  16   k . This may be done by aligning the IOL optic  31  with the IOL supporting elements  16   g,j  and aligning the haptics  30   b - e  with the haptic support elements  16   e,    16   f,  respectively.  
         [0049]     Once the IOL  30  is properly positioned in the shuttle IOL loading area  16   a , the two sections  16   k ,  16   l  are pivoted together (in the direction of arrow “a” in  FIG. 5   a ) to the closed position which encases IOL  30  between the now facing wall sections  16   k ,  16   l  ( FIG. 5   b ). With the IOL  30  thus positioned in the shuttle  16 , the shuttle  16  is closed and is then inserted into the distal section passageway  14   a  as seen in  FIG. 1  while  FIG. 10  shows the distal section  14  and shuttle  16  attached together. When fully coupled together, the proximal end  16   b  of the shuttle extends outwardly of the proximal end  14   b  of the distal section.  
         [0050]     To assist in attaching the shuttle to the distal section in the correct manner, a longitudinal groove  14   h  ( FIG. 6   d ) may be formed on an inner wall surface of distal section  14  which aligns with a longitudinal flange  16   h  formed on an outer wall surface of shuttle  16  ( FIG. 5   b ). As such, the shuttle  16  may be slidingly received within distal section  14  with groove  14   h  and flange  16   h  providing a “key” to prevent incorrect coupling between the shuttle and distal section. Furthermore, the shuttle  16  and distal section  14  may be fixed in the assembled condition through suitable mechanical locking features. For example, the shuttle  16  may be provided with a detent  16   n  and the distal section provided with a slot  14   n  which engage upon full advancement of the shuttle within the distal section. It will thus be realized that the shuttle  16  is fixed to the distal section  14 .  
         [0051]     As stated above, the shuttle  16  and IOL  30  are positioned in the distal section  14  at manufacturing and then placed in a dry package or a vial of storage solution for storage and delivery to the surgeon. For wet packaging, to ensure storage solution reaches the IOL  30 , the shuttle and distal section may each include one or more through-holes  14   p ,  16   p  which are in open communication with the IOL  30 . One of many possible embodiments of a vial is seen in  FIGS. 7 and 8   a,b , wherein a vial  11  having an open end  11   a  and an internal cavity  11   b  is provided to accept the distal section  14  and shuttle  16  with the shuttle proximal end  16   b  thereof lying adjacent the open end  11   a  of the vial. One or more longitudinally extending fins or other similar features (not shown) may be formed on the inside surface of vial  11  to align and maintain the distal section  14  at the desired orientation within vial  11 . A rigid cover or a flexible cover sheet such as a foil seal  11   c  is attached to open end  11   a  to seal the vial. Seal  11   c  may be tethered to vial  11  by a flexible hinge (not shown) if desired. This feature keeps the seal with the vial after vial opening and thereby prevents having a “loose” part in the operating suite. At the time of surgery, the package or vial  11  and distal section  14  are removed from any outer packaging in a sterile field and the vial cover seal  11   c  is removed to open vial  11  and access distal section  14  and shuttle  16 . The proximal section  12  is likewise removed from its packaging in a sterile field. The nurse or surgeon proceeds to assemble the proximal and distal sections together by inserting the distal end  12   c  of the proximal section  12  into the open end  11   a  of the vial  11  (see  FIGS. 8   a,b ). With the distal section  14  and shuttle  16  still in the vial, the proximal section open end  12   c  telescopes first over the shuttle proximal end  16   b  and then also over the distal section proximal end  14   b . It is noted that the shuttle  16  may be provided with a proximal flange  16   q  at proximal end  16   b  to assist in maintaining proper alignment between the proximal section passageway  12   a  and the shuttle  16 . Flange  16   q  may or may not touch the inner wall surface defining proximal section passageway  12   a.    
         [0052]     Further pressing of proximal section  12  against distal section end  14   b  results in the two sections attaching together. Various mechanical connection features may be employed to permit the quick and easy attachment of the proximal section  12  to the distal section  14  by simply pressing the two sections together as described above. Such features may include cooperating detents and recesses or a friction fit between the two sections, for example. In the embodiment shown in the Figures, a pair of detents  14   d,e  ( FIGS. 6   a - d ) are provided on the outer wall surface of distal section  14  which align with and engage a pair of through-holes  12   d,e  formed on proximal section  12  adjacent open distal end  12   c  thereof ( FIGS. 3   a,b ). When the proximal section  12  is pressed against the distal section  14 , the detents  14   d,e  engage the through-holes  12   d,e , respectively, and the sections become attached together. A radial flange  14   f  may be provided on distal section  14  to act as a stop against further advancement of the proximal section  12  on the distal section  14 , i.e., to prevent advancement beyond the point of detent engagement. Once the proximal and distal sections have attached together, the proximal section  12  is lifted away from the vial  11  to remove the distal section (together with shuttle  16  and IOL  30  still coupled thereto) from the vial  11 . The vial  11  and storage solution (or dry package) may then be discarded or recycled. The assembly of the injector device is now complete and the surgeon may proceed to inject the IOL  30  into a patient&#39;s eye by inserting tip  14   c  into an incision formed in the eye and pressing plunger  20  to advance the IOL  30  through and out the nozzle tip  14   c  (see  FIG. 2 ; the eye not shown for sake of clarity).  
         [0053]     Reference being made to  FIGS. 4   a,b , the plunger  20  includes distal and proximal plunger shaft lengths  20   a ,  20   b , respectively, having a plunger tip  22  at the distal end thereof and a thumb press  24  at the proximal end thereof for manually operating the injector device. The plunger tip  22  is configured for engaging the IOL optic  31  at the periphery  31   a  thereof as the plunger  20  is advanced toward the distal tip  14   c  of distal section  14 . It is very important that the plunger tip  22  not damage the IOL optic  31 . The plunger tip  22  is thus designed to prevent damage to the IOL optic  31 . In the preferred embodiment, the tip is bifurcated into first and second tip portions  22   a  and  22   b , whereby the IOL optic periphery  31   a  becomes engaged between tip portions  22   a ,  22   b  as seen in  FIG. 2B . It is understood that other plunger tip designs may be used with the present invention as desired. In one embodiment, the plunger shaft may be rotationally fixed by forming the proximal shaft length  20   a  and passageway  12   a  non-circular in cross-section. The non-circular cross-section of proximal shaft length  20   a  and passageway  12   a  prevents unwanted rotation of shaft  20  and ensure the correct orientation of tip portions  22   a  and  22   b  for grasping lens  30  every time.  
         [0054]     Furthermore, it is also advantageous to reduce the friction force between proximal shaft length  20   a  and the inner surface of proximal section  12  by reducing the contact area therebetween. This can be achieved by many plunger designs.  
         [0055]     In a particularly advantageous embodiment, the proximal length  20   a  of the plunger shaft is provided with one or more elongated flanges  20   a ′ which align with a like number of slots  12   a ′ formed between radially extending fins  21   a - d  formed on the inner wall surfaces of proximal section  12  adjacent proximal end  12   b  thereof ( FIG. 3   c ). The purpose of flanges  20   a ′ and slots  12   a ′ is to provide tactile resistance therebetween and thereby allowing the surgeon more precise control and feel when advancing the plunger. The fins  21   a - d  may be made flexible yet resilient to provide the amount of tactile resistance desired. It is understood that other ways of providing tactile resistance between the plunger and injector body are within the scope of this invention. This provides the surgeon with continuous tactile feedback allowing the surgeon to advance the plunger (and thus the IOL) through the injector device in a very concise and controlled manner. Additionally, the flanges  20   a ′ and slots  12   a ′ help provide proper centering of the plunger shaft  20  and tip  22  relative to axis X-X along which the passageways of the components lie as explained above. Upon full advancement of the plunger, it is desirable to have the plunger automatically retract to some degree upon release of finger pressure against plunger finger press  24 . In this regard, a spring  20   c  may be provided on a finger  20   d  on shaft length  20   a . As the plunger is advanced, the spring  20   c  will interact with the one or more of the fins  21   a - d  as the plunger  20  is advanced therethrough.  
         [0056]     When it is time to use the injector device, the surgeon selects a package or vial  11  having the appropriate IOL style and power preloaded in the shuttle and distal section stored in the vial as described above. The outer packaging is removed in a sterile field of the surgical suite. The proximal section having the plunger coupled thereto is also removed from its associated packaging in the sterile filed. The nurse or surgeon then attaches the proximal section  12  to the distal section  14  located in the vial in the manner described above. Once the proximal and distal sections  12 ,  14  are attached together as shown in  FIG. 2 , the surgeon inserts the distal tip  14   c  into an incision cut into the eye and begins advancing the plunger  20 . As the plunger  20  is advanced, the plunger tip  22  engages the optic periphery  31   a  and pushes IOL  30  forwardly. Upon continued advancement of the plunger  20 , the IOL  30  is pushed through the shuttle passageway  16   a  and is expressed from distal tip  14   c  and into the eye ( FIG. 2 ). As stated above, the spring  20   c  provides increasing bias in the reverse direction as the plunger reaches the fully advanced position. This occurs as spring  20   c  is compressed against one or more of the fins  21   a - d . This assists the surgeon in maintaining precise control over plunger (and hence IOL) advancement and allows automatic retraction of the plunger upon relieving the pushing pressure being exerted against the plunger thumb press  24 . This is useful for easily executing a second stroke of the plunger in order to engage and manipulate the trailing haptic into place in the eye. This feature, together with the bifurcated plunger tip  22 , allows a more precise control and manipulation of the IOL with the plunger tip in-situ than would be possible with an injector device not having these features.  
         [0057]     As discussed above, the device may be used for IOLs of any type and style. The configuration of the various component parts may likewise vary to accommodate the particular IOL style being employed with the device. Another embodiment of distal section  14 ′ and shuttle  16 ′ is seen in  FIGS. 9   a - c  for holding an IOL  30 ′ having open loop haptics  30   a ′ and  30   b ′ extending from optic  31 ′. This configuration of shuttle  16 ′ includes a longitudinal passageway  16   a ′ extending between proximal ends  16   b ′ and  16   c ′, respectively. The shuttle is divided into two longitudinal sections  16   d′,e ′ which are hinged together about living hinge  16   f′ . In the open condition of shuttle  16 ′ seen in  FIG. 9   a , IOL loading area  16   g ′ is accessible to position IOL  30 ′ thereon, on section  16   d ′, for example. IOL loading area  16   g ′ opens into and communicates with longitudinal passageway  16   a ′ which is formed when shuttle  16 ′ is in the closed condition seen in  FIGS. 9   b,c.  In this regard, registration pins  16   h ′ may be provided to engage holes  16   i ′ on sections  16   d ′,  16   e ′ to assist in aligning and correctly closing shuttle  16 ′. Various IOL placement features such as curved radius  16   j ′ and alignment pin  16   k ′, for example, may be formed on one or both sections  16   d ′,  16   e ′ to assist in proper placement of IOL  30 ′ in IOL loading  16   g′.    
         [0058]     Reference being made to  FIG. 9   c , the distal section  14 ′ may likewise vary in configuration to accommodate the configuration of shuttle being used. In this embodiment, distal section  14 ′ includes a longitudinal passageway  14   a ′ extending between proximal and distal ends  14   b ′,  14   c ′, respectively. Furthermore, one or more fingers  14   d ′,  14   e ′ extend from proximal end  14   b ′ and include a catch or other feature  14   e ″,  14   f ″ at the terminal end thereof to engage with the proximal end  16   b ′ of shuttle  16 ′. Mechanical locking features such as one or more detents  14   f ′,  14   g ′ may be formed on the outer surface of fingers  14   d ′,  14   e ′ to engage an associated recess or slot  12   d,    12   e  formed on the proximal section  12 .  
       EXAMPLES  
     Testing of Injector Devices with Surfactants  
       [0059]     In this testing, Bausch and Lomb Incorporated&#39;s Akreos Adapt™ lenses were used with injectors of the type shown in  FIGS. 1 and 2 . The injector components were made of PFA. The procedure was as follows. A lens  30  (having various optical power in the range from +10.0 d to +23.5 d) was immersed in a surfactant solution for a few seconds and then loaded in shuttle  16 , which was then positioned in distal section  14 . Distal section  14  with shuttle  16  and lens  30  positioned therein was placed in the surfactant solution for a few minutes. A proximal section  12  having a plunger  20  inserted therein was attached to distal section  14 , and ejection of lens  30  was tested. The ease of ejection, as judged qualitatively by a required amount of force, was noted. All reported surfactant concentrations are in percent by weight.  
         [0060]     Ejection was easy with a +11.0 d-power lens using 1% Polysorbate 80 solution; a +10 d-power lens and a +21.0 d-power lens using 2% Ophtasiloxane® solution (Alcon Laboratories); a +10.0 d-power lens using 1% Dimeticone (polydimethylsiloxane) solution; a +11.0 d-power lens and a +22.0 d-power lens using 2% Triton X100 (polyoxyethylene octylphenol) solution; a +10.0 d-power lens and a +17.0 d-power lens using 1% polyethylene glycol distearate solution; +18.5 d-, +19.0 d-, +20.5 d-, and +23.0 d-power lenses using 1% benzalkonium chloride solution; and +18.5 d-, +20.0 d-, +22.5 d-, +23.0 d-, and +23.5 d-power lenses using 1% Brij 30™ solution (polyoxyethylene lauryl ether).  
         [0061]     While specific embodiments of the present invention have been described in the foregoing, it will be appreciated by those skilled in the art that many equivalents, modifications, substitutions, and variations may be made thereto without departing from the scope of the invention as defined in the appended claims.