Corneal implants and methods and systems for placement

Abstract

A system comprising a hollow member is used to deliver a constrained corneal implant into a corneal pocket. The hollow member may be tapered and the system may further include an implant deformation chamber and an axial pusher to advance the implant through the hollow member.

1 . A method for delivering a corneal implant to a cornea, said method comprising:
 constraining the implant at an initial width;   advancing the implant through a tapered chamber to reduce the width of the width wherein opposed edges of the implant are curved radially inwardly as the implant is advanced; and   releasing the constrained implant into the cornea at the reduced width.   
     
     
         2 . A method as in  claim 1 , wherein the implant comprises a polymer having a tensile strength in the range from 0.1 MPa to 4 MPa and a modulus in the range from 0.1 MPa to 5 MPa. 
     
     
         3 . A method as in  claim 1 , further comprising placing the implant on a thin, flexible carrier prior to constraining the implant and the carrier. 
     
     
         4 . A method as in  claim 1 , wherein constraining comprises closing semi-circular halves of a deformation chamber on the implant. 
     
     
         5 . A method as in  claim 1 , wherein advancing comprises pushing a pusher member against the corneal implant. 
     
     
         6 . A method as in  claim 5 , wherein a forward portion of the pusher member conforms to the interior of the tapered chamber as the pusher member is pushed. 
     
     
         7 . A method as in  claim 1 , wherein the corneal implant is a biological implant. 
     
     
         8 . A method as in  claim 7 , wherein the biological implant comprises a lamellar corneal stromal endothelial transplant or DMEK graft. 
     
     
         9 . A method as in  claim 1 , wherein the implant is a synthetic implant. 
     
     
         10 . A system for delivering corneal implants, said system comprising:
 a hollow member having a proximal end and a distal end configured for insertion into a pocket within a cornea and having an axial hollow passage which tapers in the distal direction; and   an axial pusher disposed in the hollow axial passage of the hollow member to engage and axially advance a constrained corneal implant through the hollow passage,   wherein the axial hollow passage includes inwardly oriented arcuate surface which evert the edges of the corneal implant radially inwardly as the insert is axially advanced through the passage.   
     
     
         11 . A system as in  claim 10 , wherein the axial pusher includes a thin, flexible carrier for the implant and wherein the carrier has edges which are everted together with the edges of the corneal implant. 
     
     
         12 . A system as in  claim 11 , further comprising a corneal implant constrained within the hollow passage on a distal side of the axial pusher. 
     
     
         13 . A system as in  claim 11 , wherein the axial pusher is tapered in a distal direction. 
     
     
         14 . A system as in  claim 13 , wherein the axial pusher is deformable so that it will reduce in diameter as it is distally advanced through the tapered hollow passage. 
     
     
         15 . A system as in  claim 14 , wherein the axial pusher has a cross-sectional profile which is similar in shape to the cross-sectional profile of the hollow passage. 
     
     
         16 . A system as in  claim 15 , further comprising an implant deformation chamber coupled to the hollow member. 
     
     
         17 . A method for delivering a corneal implant to a cornea, said method comprising:
 forming a central anterior opening in the cornea;   introducing the implant to the opening, wherein the implant includes a center optic and a peripheral rim and wherein said peripheral rim is constrained while being introduced; and   releasing the peripheral rim from constraint so that the peripheral rim radially expands to engage corneal tissue circumscribing the central anterior opening.   
     
     
         18 . A method as in  claim 17 , wherein forming comprises creating an opening extending from an anterior corneal surface through the full thickness of the cornea. 
     
     
         19 . A method as in  claim 17 , wherein forming comprises creating a partial opening which does not extend through the full thickness of the cornea. 
     
     
         20 . A method as in any one of  claim 17 , wherein the implant is introduced in a posterior direction into the central anterior opening. 
     
     
         21 . A method as in any one of  claim 17 , further comprising forming a pocket through a lateral opening in the cornea, wherein the implant is introduced through the lateral opening into the pocket and the central anterior opening. 
     
     
         22 . A method as in  claim 17 , wherein the corneal implant has a single rim about a mid-sectional region, wherein the rim extends into corneal tissue circumscribing the central anterior opening. 
     
     
         23 . A method as in  claim 17 , wherein the corneal implant has an anterior rim and a posterior rim, wherein the anterior rim radially expands over an anterior corneal surface circumscribing the central anterior opening and the posterior rim radially expands over a posterior corneal surface circumscribing the central anterior opening. 
     
     
         24 . A method as in  claim 17 , wherein the center optic is less compressible than the rim so that the center optic is not substantially compressed as the implant is being introduced. 
     
     
         25 . A method as in  claim 17 , wherein both the rim and the center optic are compressed while the implant is being introduced. 
     
     
         26 . A method as in  claim 17 , wherein introducing comprises advancing the implant through a tube having a width which compresses at least the rim and releasing comprises advancing the implant out of the tube. 
     
     
         27 . A method as in  claim 17 , wherein the implant is introduced through a passage in the tube, wherein the passage is tapered in a distal direction to progressively compress the rim before the implant is released.