Abstract:
A preloaded injector for storing and injecting hydrophobic intra ocular lenses (IOL) comprises a plunger ( 2 ), an injector body ( 12 ), an adapter ( 16 ), a rotatable member ( 18 ), a cartridge ( 20 ) with a nozzle tube ( 22 ) and a stopper ( 26 ). The rotatable member ( 18 ) is provided around the cartridge ( 20 ) for setting the cartridge ( 20 ) from an open position to a closed position. The rotatable member ( 18 ) is furnished with a portion interfering with a portion of the stopper ( 26 ) keeping the stopper ( 26 ) irremovable in its first position but releasing the stopper ( 26 ) in its second position.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a surgical injector more particularly, the present invention relates to a preloaded injector with rotatable member for storing and injecting hydrophobic intra ocular lenses (IOL). 
       BACKGROUND 
       [0002]    An IOL is an artificial lens implanted in the eye, for example, as a replacement for the natural crystalline lens after cataract surgery or to alter the optical properties of an eye in which the natural lens remains. IOLs include an optic, and preferably at least one flexible fixation member or haptic which extends from the optic and becomes affixed in the eye to secure the lens in position. The optic normally includes an optically clear lens. Implantation of such IOLs into the eye involves making an incision in the eye. It is advantageous, to reduce trauma and speed healing, to have an incision size as small as possible. Some IOLs are foldable so that the IOL can be inserted through a smaller incision into the eye. A variety of instruments have been proposed to aid in inserting such a foldable lens in the eye. 
         [0003]    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 inserter devices which offer advantages such as affording the surgeon more control when inserting the IOL into the eye. IOL inserter devices, so called injectors, have recently been developed with reduced diameter nozzles 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]    The IOL may be made from a variety of materials or combination of materials such as PMMA, silicone, hydrogels and silicone hydrogels, etc. 
         [0005]    Two types of IDLs can be distinguished regarding the storage thereof. The hydrophilic IOLs have to be stored in fluid solvent in a container and are loaded to the injector just before inserting them into the eye. In contrast, hydrophobic IDLs can be stored in a cartridge in a dry environment. 
         [0006]    In case of hydrophilic IOLs, the IOL must first be loaded into the IOL injector. The loading of the IOL into the injector is therefore a precise and very important step in the process. An example of hydrophilic IOL and injector thereof can be seen in patent specification US2010280521 in which a retainer is provided for holding an IOL in an unstressed state. Before injection, the retainer and IOL are attached to an injector body and a compressor is moved to the closed position to compress the IOL. During injection, the compressor remains on the injector body. 
         [0007]    In the patent specification WO2007078602, an apparatus is described for loading a hydrophilic IOL into an injector. The IOL is stored in a vial and is fixed by holder mounts. In course of loading, the vial is pushed to the injector comprising a loading chamber. The loading chamber has a component that when being closed folds the lens. The goal of the apparatus is to prevent the damage of the IOL during loading. 
         [0008]    In case of hydrophobic IOLs, the IOL are stored together with the injector and there is no need of loading. Such a construction is described in patent specification EP1481652. Since the IOL is stored in the injector, special provision is needed to prevent a premature injection. Therefore a stop means shall be applied for stopping the movement of the IOL prior to the usage, during shipment and storage. The stop means is frictionally engaged on the lid of the injector, so an accidental removal can release the IOL to be injected. 
         [0009]    Unfortunately, providing the injector with additional elements for further decreasing the risk of premature injection would result in a clumsy construction which would disturb the surgeon during injection of the IOL. 
         [0010]    As it is seen from the description above, the preparation of hydrophobic IOLs for injection is a complex problem in which the preloaded IOL shall be folded as well as prevent premature injection. Constructions for hydrophilic IOL cannot be used due to the different way of loading and the different characteristic of the hydrophobic lenses. Therefore, there is a need for development of alternative solutions for a preloaded injector that would provide an injection of hydrophobic IOLs in which the folding of the IOL should be carried out in a cartridge prior to the injection but the premature injection is prevented. 
       SUMMARY 
       [0011]    We have set ourselves the objective with this invention to improve the injectors for IOLs in order to solve at least some of the aforementioned problems, by the usage of a special element that folds the IOL and can be removed before injection. Additionally the special element combines the function of folding the IOL with a double locking mechanism. 
         [0012]    Accordingly, the invention relates to a preloaded injector with rotatable member for storing and injecting hydrophobic intra ocular lenses (IOL). The injector comprises an injector body accommodating a plunger adapted to reciprocate within the injector body. A cartridge with a nozzle tube is attached to the injector body, and furnished with a winglet adapted to hinge between an open and a closed position. The cartridge is adapted to hold the IOL in a released state in case of the open position and to cause the IOL to fold in case of the closed position. A stopper prevents the plunger to move in the injector body prior to injecting. A rotatable member is provided around the cartridge for setting the cartridge from the open position to the closed position when the rotatable member is rotated from a first position to a second position. The rotatable member is furnished with a portion interfering with a portion of the stopper keeping the stopper irremovable in its first position but releasing the stopper in its second position. 
         [0013]    Due to the interaction of the rotatable member and the stopper, a double locking mechanism is established providing enhanced safeguard against premature injection by preventing the stopper to be removed before closing the cartridge. 
         [0014]    This construction allows the IOL to be folded for injection without any manipulation. Additionally, in the closed position of the cartridge, the rotatable member, which made the closing of the cartridge easier but is unnecessary in the further operations, can be removed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    For a more complete understanding of the invention, reference is made to the following detailed description of an embodiment taken in conjunction with the accompanying drawings wherein: 
           [0016]      FIG. 1  shows the parts of an embodiment of the injector in perspective view; 
           [0017]      FIG. 2  depicts the complete injector in perspective view; 
           [0018]      FIGS. 3A  . . .  3 D show the consecutive phases of preparation before injection; 
           [0019]      FIG. 4  illustrates the injector ready for injection in perspective view; 
           [0020]      FIG. 5  depicts a sectional view about the position of the stopper in the injector, 
           [0021]      FIGS. 6A and 6B  illustrate the cartridge with the IOL in open and close position. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    In the following, for purpose of explanation and not limitation, specific details of an injector for IOLs are set forth, in order to provide a thorough understanding of the present invention. It will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. 
         [0023]    As it is shown in  FIG. 1 , the injector may comprise a plunger  2 , an injector body  12 , an adapter  16 , a rotatable member  18 , a cartridge  20  with a nozzle tube  22  and a stopper  26 . The injector body  12  accommodates the plunger  2  adapted to reciprocate within the injector body  12 . The plunger  2  is furnished with a locker  10  and with a spring  4 . Additionally a soft tip  6  is inserted to one end of the plunger  2 . The injector body  12  may be provided with a finger hold flange  8  and a docking portion  14  at its end close to the cartridge. The adapter  16  can be a sleeve with rails providing connections between the rotatable member  18  and the injector body  12 . The rotatable member  18  can be a ring but any other form of construction is suitable that can turn around the axis  28  of the injector. The cartridge  20  and the nozzle tube  22  are molded in a single piece in this embodiment but they can be formed in two distinct pieces too. The cartridge  20  with a nozzle tube  22  can be attached to the injector body  12 . The IOL  24  is placed in the cartridge  20 . The lower portion of the stopper  26  can be plugged into a hole  30  of the injector body  12  through the adapter  16  preventing the plunger  2  to reciprocate in the injector body  12  prior to injecting. 
         [0024]    The reassembling steps of the injector are as follows.
       attaching the cartridge  20  with the IOL  24  to the injector body  12 ,   pulling the spring  4  and the soft tip  6  onto the plunger  2     inserting the plunger  2  into the injector body  12 ,   attaching the adapter  16  to the injector body  12 ,   inserting the stopper  26  through a hole  30  across the injector body  12  and the plunger  2 ,   pulling the rotatable member  18  on the adapter  16 .       
 
         [0031]    In  FIG. 2 , the injector can be seen after reassembling. In this state, the plunger  2 , the adapter  16  and the rotatable member  18  are fixed to the injector body  12  and are immobilized by the stopper  26 . The rotatable member  18  is depicted in a transparent manner in order to show the position of the IOL  24  in the cartridge  20 . The IOL  24  is kept in the cartridge  20  in a released state and together with the injector they are ready for packaging and for putting to the market. 
         [0032]      FIGS. 3A to 3D  show the preparation steps before use of the injector depicting only the end of the injector with a part of the injector body  12 , the stopper  26 , the adapter  16 , the rotatable member  18  and the nozzle tube  22 . The correct order of steps is shown by pictograms and numbers indicated on the surface of the rotatable member  18 , the stopper  26  and the adapter  16 . 
         [0033]    As it is seen in  FIG. 3A  number “1” informs the surgeon first to inject visco elastic material into a hole  40  on the rotatable member  18 . After injection of the visco elastic material, the rotatable member  18  has to be turned around the axis of the injector. Turning around can be made easier by means of a protrusion  42  mounted on the outer surface of the rotatable member  18 . 
         [0034]      FIG. 3B  illustrates the next step in which the rotatable member  18  is turned around. This step is indicated by a number “2” with an arrow above “̂”, showing the direction of turning. By turning around, the rotatable member  18  around the cartridge is rotated from a first position to a second position by which the cartridge is made from an open position to a closed position. If the cartridge is closed, it cannot be opened any more. The closing of the cartridge will be described later in  FIGS. 6A, and 6B . 
         [0035]    In  FIG. 3C , the next step can be seen when the stopper  26  is removed. Since the rotatable member  18  is furnished with a portion interfering with a portion of the stopper  26  keeping the stopper  26  irremovable in the first position of the rotatable member  18  but releasing the stopper  26  in its second position. This step is indicated by a number “3” with an arrow above “̂”, showing the direction of removing. Removing can be carried out just because interfering portions such as a recess  34  on the edge of the rotatable member  18  fits to a protrusion  32  mounted on the leg of the stopper  26 . It can be highlighted that rotation of the rotatable member  18  has double functions, i.e. it closes the cartridge and releases the stopper  26 . 
         [0036]    The final step is shown in  FIG. 3D  in which the adapter  16  and the rotatable member  18  are removed from the cartridge  20  and the injector body  12 . The step is indicated by a number of “4” with an arrow above “̂” on the surface of the adapter  16 . Another arrow depicted on a protrusion  44  on the outer surface of the adapter  16  shows the direction of removing. After removing it can be seen that the adapter  16  staying between the cartridge  20  and the rotatable member  18  is provided with rails both for connection to the injector body  12  and to the rotatable member  18 . The rail to the injector body  12  can be a groove  38  fitting to a feather  36  on the injector body  12  longitudinal to the axis  28  of the injector. The rail to the rotatable member  18  can be a ring shaped stop-shoulder  46  around the outer surface of the adapter  16 . If the rotatable member  18  is shaped as a conical ring, and the inner diameter of the ring at the end close to the stop-shoulder  46  is smaller than the outer diameter of the stop-shoulder  46 , the adapter  16  and the rotatable member  18  are fixed to each other and they can be removed from the injector body  12  together only. 
         [0037]    In  FIG. 4 , the injector can be seen ready for injection. After removing the rotatable member  18  with the adapter  16 , the injector may comprise the plunger  2 , the injector body  12  and the closed cartridge  20  with the nozzle tube  22  only. In this state the injector possesses the necessary elements only for the injection without any elements that are not needed any more. 
         [0038]      FIG. 5  illustrates an axial sectional view of the relation among the stopper  26 , the rotatable member  18 , the cartridge  20  and the injector body  12  in that phase in which the rotatable member  18  is turned to its second position in course of closing the cartridge  20 . The soft tip  6  attached to the end of the plunger  2  is stopped by the stopper  26  preventing any premature injection. The injection is allowed when the stopper  26  is removed. The removal of the stopper  26  is possible since by turning the rotatable member  18  to its second position, the recess  34  on its edge is positioned just above the protrusion  32  of the stopper  26 . In the first position of the rotatable member  18 , the recess  34  does not lay above the protrusion  32  so it is not possible to remove the stopper  26 . In this way a double locking mechanism is established providing enhanced safeguard against premature injection. I.e. 
         [0039]    1) the plunger  2  cannot be reciprocated in the injection body  12  before removal of the stopper  26 ; 
         [0040]    2) the stopper  26  cannot be removed before rotating the rotatable member  18  to its second position and thereby closing the cartridge  20 . 
         [0041]    During injection the plunger  2  is pushed in the injector body  12  whereby the soft tip  6  reaches the IOL  24  and makes it move from the cartridge  20  through the nozzle tube  22  to the outer space. The soft tip  6  is made of an elastic material dynamically fitting to the interior of the cartridge  20  and the nozzle tube  22  during the injection. The locker  10  on the plunger  2  is adapted to bump at the end of the injector body  12  just before the soft tip  6  arrives at the distal end of the nozzle tube  22 , preventing the soft tip  6  leaving the nozzle tube  22  during the injection. 
         [0042]      FIG. 6A , shows the cartridge  20  with the nozzle tube  22  holding the IOL  24 . The cartridge  20  has a winglet  50  that can hinge on the cartridge  20 . The winglet  50  is open i.e. the cartridge is in open position so the IOL  24  is in a released state. 
         [0043]      FIG. 6B  shows the closed position of the cartridge  20  in which the winglet  50  is closed to the cartridge  20  causing the IOL  24  to fold. In the closed position the interior of the cartridge  20  together with the interior of the winglet  50  form a tubular inner space co-axial to the nozzle tube  22 . 
         [0044]    Although one preferred embodiment of the present invention has been illustrated in the accompanying drawings and described in the foregoing detailed description, it is understood that the invention is not limited to the disclosed embodiment but is capable of numerous rearrangements, modifications, and substitutions for IOL injectors without departing from the invention.