Abstract:
An intraocular insertion device capable of safely performing discharge operation of a lens by a simpler construction. The intraocular lens insertion device has a body provided with a lens placement section where the lens is placed and a tube section for inserting the lens into an eye and has a plunger for discharging the lens placed on the lens placement section. The lens placement section has an upper holding member and a lower holding member. The upper holding member has a rib projecting on advancement axis A, to the lower side of the lens placement section. The lower holding member has a U-shaped cross-section and is constituted of a left and right pair of uprising sections and a pressing section uniting the uprising sections at their lower ends.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a U.S. national phase application under 35 U.S.C. § 371 of International Patent Application No. PCT/JP2006/300217 filed Jan. 11, 2006, which claims priority to Japanese patent application No. 2005-018850, filed Jan. 26, 2005. The International Application was published in Japanese on Aug.3, 2006 as International Publication No. WO 2006/080191 A1 under PCT Article 21(2). The content of both applications is incorporated herein in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to an intraocular lens insertion device that inserts an intraocular lens into an aphakic eye after a cataract operation, or, to an intraocular lens insertion device that inserts a phakic intraocular lens during a refractive surgery. 
       DESCRIPTION OF THE RELATED ART 
       [0003]    In cataract operations, the method of removing an opacified lens by phacoemulsification (PEA) and implanting an intraocular lens after the opacified lens has been removed is widely performed. The types of implanting intraocular lens include a hard intraocular lens with an optical area made of a hard material, such as (PMMA), and a soft intraocular lens made of a soft material such as silicone elastomer or soft acrylic resin. When using a hard intraocular lens, the intraocular lens must be inserted through an incision in the cornea or sclera that is of about the same width as the diameter of the optical area but, when using a soft intraocular lens, folding of the optical area allows the intraocular lens to be inserted into the eye through an incision that is smaller than the diameter of the optical area. Further, performing the operation with a smaller incision is desirable because it reduces the risk of post-surgery corneal astigmatism and infection, so there has been a trend in recent years to favor the use of soft intraocular lens. In addition, to insert the lens into the eye, there are cases where a special injector having a long tube through which the lens passes as it is guided into the eye is used. Using such a special intraocular lens injector makes it possible to insert the lens through an incision smaller than 3 mm. 
         [0004]    In addition, preset injectors having the lens set in the injector in advance to eliminate the risk of contamination by microbes during lens handling and of possible operational mistakes during lens handling have recently been announced. Some preset injectors are provided with a lens holding mechanism that holds the lens inside the injector in a state that does not stress the optical area and with a lens movement mechanism that moves the lens to a position where it can be pushed out by an discharge device so as to transfer the lens from the lens immovable state during shipment to the lens movable state during use (For example, refer to Japanese Patent Application Laid-Open (JP-A) No. 2003-325570 (“JP &#39;570”), and JP-A No. 2003-325572 (“JP &#39;572”)). 
       SUMMARY OF THE INVENTION 
       [0005]    However, a characteristic of the invention disclosed in the above-mentioned JP &#39;570 and JP &#39;572 is that during use the lens must be moved from the holding position to a position from where it can be discharged, and there is concern that problems will occur during the moving operation. In addition, the construction is such that after moving the lens to a position where it can be discharged, the lens is folded while being discharged from a state where the optical area is nearly undeformed, so the movement distance required by the discharge mechanism is long, which creates the problems of trouble occurring during discharge and of the insertion device needing to be large. 
         [0006]    In view of the above, an object of the present invention is to provide an intraocular lens insertion device having a simple construction that safely performs the lens discharge operation and solves the afore-mentioned problems. 
         [0007]    To achieve the afore-mentioned objective, the present invention according to a first aspect of the invention is an intraocular lens insertion device that is characterized by a body having a lens placement section that holds the lens and a tubular body that guides the lens, and a lens discharge mechanism set in the lens advancement axis, wherein the afore-mentioned lens placement section is provided with a deformation mechanism to having an upper holding member that holds the lens from above along the advancement axis from back to front and a lower holding member that holds both sides of the lens from below to hold the lens on the advancement axis. 
         [0008]    In addition, the present invention according to a second aspect of the invention is characterized by the afore-mentioned upper holding member that holds the lens by the edge. 
         [0009]    In addition, the present invention according to a third aspect of the invention is characterized by the afore-mentioned upper holding member having a contact surface with the lens comprising an arc with a radius of curvature smaller than the lens optical area. 
         [0010]    In addition, the present invention according to a fourth aspect of the invention is characterized by the afore-mentioned upper holding member having formed therein a insertion pass-through groove thorough which the afore-mentioned lens discharge mechanism passes parallel to the advancement axis. 
         [0011]    In addition, the present invention according to a fifth aspect of the invention is characterized by the afore-mentioned lower holding member provided with a partition placed between the lens and the afore-mentioned lens discharge mechanism and a locking section having an insertion pass-through hole through which the afore-mentioned lens discharge mechanism passes. 
         [0012]    The intraocular lens insertion device according to the first aspect of the present invention can push up the lower holding member while holding the lens in the advancement axis to fold into two the lens to eliminate the need to move the lens and allow the device to be made smaller. 
         [0013]    In addition, the intraocular lens insertion device according to the second aspect is provided with an upper holding member that holds the edge of the lens such that the lens can be held without deforming the curved lens. 
         [0014]    In addition, the intraocular lens insertion device according to the third aspect can prevent the contact surface of the upper holding member from contacting the optical area of the lens and can hold the lens without deforming the curved optical area, due to the curved shape of the contact surface viewed from the side. 
         [0015]    In addition, the intraocular lens insertion device according to the fourth aspect is provided with an upper holding member formed with an insertion pass-through groove having a width nearly the same or larger than the outside shape of the lens discharge mechanism such that the lens discharge mechanism does not contact the upper holding member so that there is no interference with the lens discharge operation and the lens can be smoothly discharged even if the lens discharge mechanism is offset in the upward direction. 
         [0016]    In addition, the intraocular lens insertion device according to the fifth aspect is provided with a lower holding member that can fold in two the lens using an upward pushing motion and that can unlock the plunger to perform the operation in a simpler manner. Further, the plunger is locked by the locking section to prevent operational mistakes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0017]      FIG. 1  is a complete oblique perspective view showing the construction of the intraocular lens insertion device according to an embodiment of the present invention. 
           [0018]      FIG. 2  is a vertical cross-section view of the construction of the lens placement section showing the holding state. 
           [0019]      FIG. 3  is a cross-sectional view of  FIG. 2  taken on a B-B line showing the holding state. 
           [0020]      FIG. 4  is a vertical cross-section of the lens placement section showing the dischargeable state. 
           [0021]      FIG. 5  is a cross-section of  FIG. 4  taken on a C-C line showing the dischargeable state. 
           [0022]      FIG. 6  is a vertical cross-section of a modified example of the lens placement section showing the holding state. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]    The following describes preferred embodiments of the present invention with reference to the drawings. 
         [0024]    The intraocular lens insertion device  1  shown in  FIG. 1  is used to safely and quickly discharge into an eye a deformable intraocular lens  2  (hereinafter referred to as “lens  2 ”), and more particularly is a preset type intraocular lens insertion device  1  having a lens  2  preset in the intraocular lens insertion device  1 . More specifically, the intraocular lens insertion device  1  is provided with a body  5  having a lens placement section  3  that holds the lens  2  and a tube section  4  that inserts the lens  2  into an eye, and a plunger  6  serving as a lens discharge mechanism that discharges the lens  2  that is placed in the afore-mentioned lens placement section  3 . 
         [0025]    The lens  2  used here may be made of a soft material, such as silicone resin, acrylic resin, or hydrogel. 
         [0026]    The afore-mentioned body  5  is constructed of a tubular material and comprises the afore-mentioned tube section  4  whose end is cut off at an angle, a cylindrical section  7  formed with an outside shape that is wider than that of the afore-mentioned tube  4 , and a tapered section  8  that joins the afore-mentioned tube section  4  and afore-mentioned cylindrical section  7 . The afore-mentioned cylindrical section  7  comprises the lens placement section  3  that is placed on the end provided with the tube section  4 . The proximal end of the afore-mentioned body  5  is provided with a flange  9  that protrudes in the radial direction of the body  5 . Note that since the tube section  4  is inserted into the incision made in the eye ball, it must be made of a material that does not have a negative impact on the human body, such as polypropylene or other thermoplastic resin, for example. 
         [0027]    The afore-mentioned body  5  is provided with a support member not shown in the figure that holds the plunger  6  in the position where the lens  2  can be discharged thereby and that supports the same in a manner capable of moving in the anteroposterior direction inside the body  5 . 
         [0028]    The afore-mentioned lens placement section  3  is provided with a deforming mechanism  11 , and this deforming mechanism  11  is formed so as to be integrated with the body cylindrical section  7  and comprises an upper holding member  12  composed of a top plate  7   a  and side plates  7   b  of the body  5 , and a lower holding material  14  that is mounted so as to cover an opening  13  that is formed in the bottom of the upper holding material  12  as shown in  FIG. 2 . 
         [0029]    The afore-mentioned top plate  7   a  is provided with a rib  15  that protrudes downward in the direction of the afore-mentioned advancement axis A, and the afore-mentioned side plates  7   b  are provided with a concave engagement area  16  that engages with a hereafter-mentioned convex engagement area. The afore-mentioned rib  15  has a curved section  17  on a contact surface  15   a  that is curved upward as seen from the side, and this curved section  17  is formed by an arc having a radius of curvature that is smaller than that of the optical area of the lens  2  as shown in  FIG. 3 . Providing this curved section  17  makes it possible for the upper holding member  12  to hold the lens  2  by the edge of the lens  2 . 
         [0030]    As shown in  FIG. 2 , the afore-mentioned lower holding member  14  is formed by uprising sections  18  that protrude upward, and engagement sections  19  that engage from the outside of the afore-mentioned side plates  7   b  formed on the outside of the uprising sections  18 , positioned on the right and left sides facing each other, and the afore-mentioned uprising sections  18  and the afore-mentioned engagement sections  19  are united into a single piece by a pressing section  20  at the bottom. The uprising sections  18 , which are formed facing each other on the opposite sides left and right having the advancement axis A in the center consist of a placement surfaces  21 , an inclined surfaces  22  that inclines downward towards the center, and an arc surface  23  that unites the inclined surfaces  22  at the center. 
         [0031]    Between the afore-mentioned uprising sections  18  and engagement sections  19  is formed a groove section  24  into which is inserted the afore-mentioned side plate  7   b . The afore-mentioned engagement sections  19  are provided with a protruding engagement section  25  that protrudes facing the body&#39;s side plate  7   a , and the protruding engagement section  25  is provided on a movable member  27  cut with slits  26  ( FIG. 1 ). The afore-mentioned protruding engagement section  25  and the concave engagement area  16  have a multiplicity of steps in the perpendicular direction to allow incremental positioning in the vertical direction of the lower holding member  14  in relation to the upper holding member  12  ( FIG. 2 ). 
         [0032]    Further, an uprising locking member  30  is formed as an up rise, constructed by a reverse U-shaped plate member on the base end side of the lower holding member  14 . The locking member  30  comprises a partition  31  formed as an up rise on the rear end of the afore-mentioned pressing section  20  such that it intersects perpendicularly with the advancement axis A, and an insertion pass-through hole  32  that is formed in the approximate center of the bottom of the partition  31 . 
         [0033]    Next, the action of the afore-mentioned construction is explained. First, the lens  2  is placed in the lens placement section  3 . More specifically, as shown in  FIG. 2 , the lens  2  is placed on the placement surface  21  in the lower holding member  14 . The lower holding member  14  in which is placed the lens  2  allows the side plate  7   b  to be inserted into the groove section  24 . When the side plate  7   b  is inserted into the groove section  24 , the lower holding member  14  is further pushed up. When the lower holding member  14  is pushed up, the protruding engagement section  25  engages with the concave engagement section  16  and is mounted on the upper holding member  12 . At this time, the lower holding member  14  is positioned by the protruding engagement section  25  such that the top of the lens  2  makes contact with the contact surface  15   a  of the rib  15 . 
         [0034]    In addition, as shown in  FIG. 3 , the contact surface  15   a  of the upper holding member  12  has the curved section  17  that prevents the contact surface  15   a  from making contact with the optical area of the lens  2  to hold the lens  2  without deforming the curved optical area. Further, the front and back edges of the contact surface  15   a  are formed to make contact with the lens  2  to hold the lens  2  while preventing the lens  2  from being displaced in the anteroposterior direction. In this manner, the lens  2  is held in place in the advancement axis A. More specifically, a part of the lens  2  is placed in the advancement axis A and held in a position where it can be discharged by the plunger  6 . In this way, the positional relationship in the advancement axis A between the lens  2  and the plunger  6  is such that there is no change before and after deformation of the lens  2  in the lens placement section  3 , which allows the plunger  6  to securely press against the specified area of the lens  2 . Further, the plunger  6  is positioned to the rear of the lens  2  in the advancement axis A, but the placement of the locking member  30  between the lens  2  and the end of the plunger  6  impedes the forward movement of the plunger  6  to prevent the lens  2  from being mistakenly discharged. In addition, the protruding engagement section  25  formed in the uprising sections  18  engages with the concave engagement area  16  formed in the inside surface of the hole  24 , mounted on the lens placement section, so that the lower holding member  14  prevents the lens  2  from being mistakenly folded into two during transport, etc., and, further, the locking member  30  locks the plunger  6  to prevent mistaken operation. 
         [0035]    Next, the deforming of the lens  2  set in the lens placement section  3  is explained. As shown in  FIG. 4 , the afore-mentioned lower holding member  14  is pushed upwards. More specifically, when the pressing section  20  is pushed upwards, the engagement areas between the protruding engagement section  25  formed in the engagement sections  19  and the concave engagement areas  16  formed in the side plates  7   b  move upward. When the engagement areas between the protruding engagement section  25  and the concave engagement areas  16  move upward, the uprising sections  18  move upward. When the uprising sections  18  move upward, the inclined surfaces  22  make contact with the lens  2  and push up the lens  2 . When the lens  2  is pushed up by the inclined surfaces  22 , the center of the lens  2  is held from above by the rib  15  formed along the advancement axis A to fold into two the lens  2  in a U-shape. At this time, the afore-mentioned protruding engagement area is provided in the afore-mentioned movable member  27 , so pushing up the lower holding member  14  elastically deforms the moveable member  27  in the outward direction to release the engagement and allow the engagement areas to easily move upward. 
         [0036]    In addition, the upward movement of the engagement between the protruding engagement sections  25  and the concave engagement areas  16  moves the locking member  30  upwards as shown in  FIG. 5 . When the locking member  30  moves upward, the partition  31  that covers the end of the plunger  6  moves upward. When the partition  31  moves upward, the insertion pass-through hole  32  moves along the advancement axis A to release the lock of the plunger  6 . In this way, the lens  2  is moved along the advancement axis A without being moved in the upward direction. More specifically, the lens  2  is folded into two by the plunger  6  while being held in a position where the lens  2  can be discharged, which allows the intraocular lens insertion device  1  to be made smaller and to eliminate problems that accompany the moving of the lens  2 . Further, the lens  2  can be folded into two before it is discharged, so a shorter distance is required for the lens  2  to be discharged than when the lens  2  is incrementally deformed by passing it through the tapered section, which allows the body  5  to be made smaller. In addition, the upward pushing motion of the pressing section  20  can fold the lens  2  into two while also releasing the lock of the plunger  6  to allow the operation to be performed more simply. 
         [0037]    Then, the lens  2 , which has been folded into two, is discharged by the plunger  6 , the lock of which has been released, and is inserted into the eye from the tube section  4 . Since the fingers can hang onto the flange  9 , the plunger  6  discharge operation can be done smoothly. 
         [0038]    Next, a modified example of the afore-mentioned embodiment is explained making reference to  FIG. 6 . Note that when the configuration is the same as the afore-mentioned configuration, the same numbers are used and the explanation is omitted for simplification. 
         [0039]    As shown in  FIG. 5 , the upper holding member  12  is formed with an insertion pass-through groove  35  that extends parallel to the advancement axis A in the center of the rib  15 . This insertion pass-through groove  35  has the same or a slightly larger width than outside shape of the afore-mentioned plunger  6 . In this manner, by forming the insertion pass-through groove  35  in the rib  15 , the advancement of the plunger  6  when the plunger  6  discharges the lens  2  is not hindered by the rib  15 . More specifically, even if the plunger  6  is off set in the upward direction, the rib  15  is formed with the insertion pass-through groove  35  having a width the same or slightly larger than the plunger  6 , so the plunger  6  does not make contact with the rib  15 . Therefore, the lens  2  can be smoothly discharged without the hindering of the operation that discharges the lens  2 . Further, the rib  15  holds the center of the lens  2  along the advancement axis A, which makes it possible for the upward movement of the uprising sections  18  to fold the lens  2  into two. 
         [0040]    As described above, this embodiment according to the first aspect is the intraocular lens insertion device  1  that is provided with the body  5  having the lens placement section  3  that holds the lens  2  and the tube section  4  that guides the lens  2  and the plunger  6  that is installed in the advancement axis A, wherein the afore-mentioned lens placement section  3  is provided with the deformation mechanism  11  comprising the upper holding member  12  that holds the lens  2  from above along the advancement axis A from back to front and the lower holding member  14  that holds the lens  2  from both sides to allow it to be pushed up from below, and by holding the lens  2  in the advancement axis A, it is possible to maintain the lens  2  in the advancement axis A while pushing up the lower holding member  14  to fold the lens  2  into two, so it is not necessary to move the lens  2 , which allows the intraocular lens insertion device  1  to be made smaller. 
         [0041]    In addition, according to the second aspect, the afore-mentioned upper holding member  12  holds the lens  2  by the edges of the lens to allow the lens  2  to be held without deforming the optical area  2   a  of the curved lens  2 . 
         [0042]    In addition, according to the third aspect, the afore-mentioned upper holding member  12  having the contact surface  15   a  with the lens  2  having the curved section  17  formed by an arc having a radius of curvature that is smaller than that of the optical area of the lens  2  whereby the contact area  15   a  is prevented from contacting the optical area of the lens  2 , which allows the lens  2  to be held without deforming the curved optical area. 
         [0043]    In addition, according to the fourth aspect, the afore-mentioned upper holding member  12  is formed with the insertion pass-through groove  35  through which passes the afore-mentioned plunger  6  in parallel to the advancement axis A, and the upper holding member  12  is formed with the insertion pass-through groove  35  having a width approximately the same or larger than that of the outside diameter of the plunger  6 , which makes it so that the plunger  6  does not contact the upper holding member  12  even if the plunger  6  is off set in the upward direction. This allows the lens  2  to be smoothly discharged. 
         [0044]    In addition, according to the fifth aspect, the afore-mentioned lower holding member  14  is provided with the locking member  30  comprising the partition  31  placed between the lens  2  and the afore-mentioned plunger  6  and the insertion pass-through hole  32  through which passes the afore-mentioned plunger  6  to make possible the performance of a simple operation that folds into two the lens  2  by the operation of pushing upward the lower holding member  14  while also unlocking the lock of the plunger  6 . Further, the plunger  6  is locked by the locking member  30  to prevent mistaken operation. 
         [0045]    The present invention is not limited by the foregoing embodiments and a variety of deformation embodiments within the intended scope of the present invention are possible.