Intraocular lens delivery device with a multi-part plunger tip

Abstract

The present invention is directed to the provision of an intraocular lens delivery device having a plunger with a multi-part plunger tip. The plunger tip includes a first part and a second part wherein the first part releases from the second part during travel of the plunger through the body of a delivery cartridge.

1 . An IOL delivery device, the device comprising:
 a delivery cartridge having an internal surface defining a lumen extending along the cartridge wherein at least a portion of the lumen has a cross-sectional area that becomes progressively smaller as the cross-sectional area is taken at locations progressively closer to a nozzle of the cartridge; and   a plunger having a plunger tip, the plunger tip being defined by an internal member, an external member and a intermediate member, the external member being formed of a relatively compressible material and the intermediate member being formed of a relatively non-compressible material;   wherein, during delivery of an IOL, the plunger tip travels along the at least a portion of the lumen causing the external member to compress a substantial amount while the intermediate member remains substantially non-compressed and wherein, upon achieving the substantial amount of compression, the internal member releases from the intermediate member and continues the delivery of the IOL.   
   
   
       2 . An IOL delivery device as in  claim 1  wherein the external member is formed of a material having an elongation at break that is at least 350%. 
   
   
       3 . An IOL delivery device as in  claim 1  wherein the external member is formed of a material having an elongation at break that is at least 800%. 
   
   
       4 . An IOL delivery device as in  claim 1  wherein the intermediate member is formed of a material having an elongation at break that is no greater than 300%. 
   
   
       5 . An IOL delivery device as in  claim 1  wherein the intermediate member is formed of a material having an elongation at break that is no greater than 100%. 
   
   
       6 . An IOL delivery device as in  claim 1  wherein the external member is formed of a first material, the intermediate member is formed of second material and the first material has an elongation at break that is at least 2× an elongation at break of the second material. 
   
   
       7 . An IOL delivery device as in  claim 1  wherein the external member is formed of a first material, the intermediate member is formed of second material and the first material has an elongation at break that is at least 4× an elongation at break of the second material. 
   
   
       8 . An IOL delivery device as in  claim 1  wherein the internal member is an end portion of a shaft of the plunger. 
   
   
       9 . An IOL delivery device as in  claim 1  wherein the delivery cartridge include a stop feature that stops the travel of the external member after the substantial amount of compression of the external member. 
   
   
       10 . An IOL delivery device as in  claim 1  wherein the material that forms the external member includes a substantial portion of elastomer. 
   
   
       11 . An IOL delivery device as in  claim 10  wherein the external member includes at least 30% by weight elastomer. 
   
   
       12 . An IOL delivery device as in  claim 10  wherein the external member includes at least 50% by weight elastomer. 
   
   
       13 . An IOL delivery device, the device comprising:
 a delivery cartridge having an internal surface defining a lumen extending along the cartridge wherein at least a portion of the lumen has a cross-sectional area that becomes progressively smaller as the cross-sectional area is taken at locations progressively closer to a nozzle of the cartridge; and   a plunger having a plunger tip, the plunger tip being defined by an internal member, an external member and a intermediate member, the external member being formed of a relatively compressible material and the intermediate member being formed of a relatively non-compressible material;   wherein, during delivery of an IOL, the plunger tip travels along the at least a portion of the lumen causing the external member to compress a substantial amount while the intermediate member remains substantially non-compressed and wherein, upon achieving the substantial amount of compression, the internal member releases from the intermediate member and continues the delivery of the IOL; and   wherein the internal member, the external member, the intermediate member or a combination thereof includes one or more retention features for releasably maintaining the intermediate member the external member or both in the same position relative to the internal member until the internal member releases from the intermediate member.   
   
   
       14 . An IOL delivery device as in  claim 13  wherein the external member is formed of a material having an elongation at break that is at least 800%. 
   
   
       15 . An IOL delivery device as in  claim 13  wherein the intermediate member is formed of a material having an elongation at break that is no greater than 100%. 
   
   
       16 . An IOL delivery device as in  claim 13  wherein the external member is formed of a first material, the intermediate member is formed of second material and the first material has an elongation at break that is at least 4× an elongation at break of the second material. 
   
   
       17 . An IOL delivery device as in  claim 13  wherein the delivery cartridge include a stop feature that stops the travel of the external member after the substantial amount of compression of the external member. 
   
   
       18 . An IOL delivery device as in  claim 13  wherein the external member includes at least 30% by weight elastomer.