Abstract:
An insertion instrument provides improved features for insertion of a lens into the eye through a small incision. A tubular member has a lumen and a split nozzle end portion for spreading after insertion. Ridges on the lumen wall prevent rotation of the lens, and stabilizer components extend from a plunger end portion to maintain the lens compressed and to prevent lens rotation in moving through the lumen.

Description:
RELATED APPLICATION  
       [0001]    The present application is related to Applicant&#39;s pending application Ser. No. 08/751,181 which shows and describes some related features. 
     
    
     
       BACKGROUND AND SUMMARY OF THE INVENTION  
         [0002]    The present invention addresses problems related to the insertion of an intraocular lens through a small incision in the human eye.  
           [0003]    Reference is made to Applicant&#39;s related application Ser. No. 08/751,181, wherein are illustrated and described certain relevant features and components, which application is incorporated herein by reference.  
           [0004]    In recent years, foldable intraocular lenses have largely replaced hard, rigid lenses, the foldable lens being insertable through an incision of approximately {fraction (1/2)} the size of an incision required for rigid lenses. A small incision enables more rapid recovery, less discomfort for a patient, and avoids many of the possible adverse complications of cataract surgery. Further, the procedure requires less time because suturing is not required.  
           [0005]    The problems addressed include undesirable rotation of a folded, compressed lens during passage through a lumen or tubular passage, the maintaining of the correct orientation of a lens relative to an insertion instrument, sudden expansion of unfolding of a compressed lens as it exits the insertion instrument into the eye, and difficulty in insertion of a tip of an insertion instrument into a small incision in the eye of a patient.  
           [0006]    Although various folding forceps have been provided for folding flexible lenses, it has generally been preferred by surgeons to utilize insertion devices whereby a lens enters the eye through a tube. Folding forcep devices generally comprise two components in addition to a lens, thus requiring two hands for their utilization.  
           [0007]    The improvements according to the invention include a plunger with stabilizing components thereon to exert forces on a folded lens to maintain the lens in folded configuration and to prevent rotation of the lens relative to a lumen wall.  
           [0008]    One or more slits in the nozzle end portion enable the spreading of the end portion by passage therethrough of the folded lens after insertion in the eye of a patient, thus to provide ease of admission of the folded lens into the eye of a patient.  
           [0009]    Ridges extend longitudinally of the lumen wall to aid in prevention of rotation of a folded lens relative to the lumen wall., these including ridges extending along opposite edges of at least one slit in the nozzle end portion of the insertion instrument to aid in the prevention of rotation of a folded lens relative to the lumen wall. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is an exploded perspective view of an insertion instrument of the present invention showing its receptacle actuator, tubular portion and nozzle;  
         [0011]    [0011]FIGS. 2 and 3 are sectional views of the instrument of FIG. 1, showing a Lens optic and haptics in folded configuration in the lumen with the nozzle tip inserted through an incision in the eye of a patient;  
         [0012]    [0012]FIG. 4 is an enlarged fragmentary view of the nozzle portion, showing the nozzle tip portion inserted via an incision in the eye of the patient, and the lens expanding within the eye;  
         [0013]    [0013]FIG. 5 is a perspective view of a plunger and stabilizer components thereon, according to the present invention;  
         [0014]    [0014]FIG. 6 is a perspective cutaway view of the plunger and stabilizers thereof in relation to a folded lens optic and haptics in the lumen of the instrument of FIGS. 2 and 3;  
         [0015]    [0015]FIG. 7 is an enlarged partial sectional view, taken at line  7 - 7  in FIG. 6;  
         [0016]    [0016]FIGS. 8, 9 and  10  are sectional views taken at lines  8 - 8 ,  9 - 9 , and  10 - 10  in FIG. 1, showing a folded lens in different configurations in the plunger at successive positions in moving through the lumen; and  
         [0017]    [0017]FIGS. 11A and 11B are sectional views showing the interrelationship among the ram, lumen and lens in the folding of the lens into folded configuration in a pre-insertion position in the lumen-tube.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]    Referring to the drawings, there is shown an improved insertion instrument  10  for inserting an intraocular lens into a patient&#39;s eye via a small incision. The instrument generally includes a lens insertion assembly  12  and an insertion actuator  14 . The lens insertion instrument is adapted to receive a foldable intraocular Lens  16  in an unfolded configuration.  
         [0019]    As utilized herein for purposes of description, the terms “horizontal”, “vertical”, “upward” and “downward” are defined in relation to preferred orientation normally employed by a surgeon in using the instrument in the insertion of an intraocular lens into the eye of a patient. In this context, “horizontal” is a longitudinal direction of the instrument and plunger as indicated in FIGS. 1 and 5, and “vertical” is the direction perpendicular to such horizontal orientation. However, the insertion instrument may be utilized in other orientations.  
         [0020]    The lens insertion assembly  10  includes a receptacle  18  and an elongate tubular portion  20  which has an interior passage or lumen  21 , a nozzle  22 , and a tip  24  for insertion into the eye, the nozzle having a longitudinal slit  25 , as shown. The nozzle and tubular portion may typically be fabricated of polycarbonate, polyethylene, polystyrene, or other plastic with adequate flexibility.  
         [0021]    The lumen or bore  21  extends axially through tubular portion  20 , and has a longitudinal central axis. The receptacle  18  is preferably formed integrally with the tubular portion and has a lens storage chamber  26  extending laterally of bore  24  through an opening (not shown) in the wall of the bore.  
         [0022]    The foldable lens  16  is formed of appropriate flexible optical lens material, and has a central optic  28  and generally flat plate haptics  30  joined to opposite edges of the optic in a generally common plane transverse to the optic axis. Other types of foldable lenses may be utilized.  
         [0023]    The lens storage chamber  26  receives the lens in its unfolded configuration. A ram  32  serves as lens transfer and folding means, and cooperates with the chamber and receptacle  18  to define the lens storage space. The ram is operable by the user to move the unfolded lens from this storage position into the lumen or bore  21  (FIG. 11A) via the opening in the bore wall, and to fold the lens into a compact folded configuration with the lens in a pre-insertion position in the bore or lumen (FIG. 11B).  
         [0024]    The ram and receptacle have mating interfitting male and female configurations of slots  34  and ram wing portions  36 . Referring to FIGS. 11A and 11B, the inner end of the rain has an arcuate end face  38  across which extends a transverse ridge  32  which is aligned with the longitudinal axis of the bore or lumen  21 . The inner curvature  38  of the ram is curved like the inner surface of the bore or lumen (FIG. 111B). The end surface or face  38  of the ram is flush with the inner wall surface of the lumen and faces the opposing wall surface of the bore.  
         [0025]    A plunger  40  (best shown in FIG. 5) constitutes lens insertion means to move the folded lens from its pre-insertion position through the lumen and tip  24  to eject the lens through the tip into the eye of the patient. The Lens is, in effect, wrapped about the plunger end portion in moving through the lumen.  
         [0026]    Manual operation of insertion actuator  14 , which is preferably a rack and pinion arrangement, as shown, causes the end of plunger  40  to engage the lens in its pre-insertion position, and to urge the lens along the lumen toward nozzle  22  and tip  24 , and thence into the eye of the patient.  
         [0027]    A longitudinal ridge  58  is defined on the lumen wall (FIG. 8) and is aligned with ridge  32  on the inner ram surface to prevent rotation of the lens relative to the lumen wall.  
         [0028]    Ridges  60 ,  62  are defined at opposite edges of slit wall. These ridges retain the lens against rotation relative to the lumen wall during movement along the lumen.  
         [0029]    In moving through the lumen and nozzle, the folded lens has the successive configurations indicated in FIGS. 8, 9 and  10 , the lens being gradually opened to the configuration of FIG. 10.  
         [0030]    In passing through the nozzle and the outlet or tip  24 , the slitted end portions of the nozzle and tip are spread open, the spreading being limited by the sides of the incision in the eye.  
         [0031]    Thus there has been shown and described an intraocular lens insertion instrument which fulfills all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification together with the accompanying drawings and claims. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.