Method and system for packaging of medical devices including shape memory materials

Abstract

Methods and systems are described for packaging medical devices. Packages are described for constraining expansion of medical devices along at least one axis. Removal devices for removing the medical devices from the packages are described. Medical devices stored in and removed from packages can include shape memory materials (e.g., polymers, alloys) which can cause the medical device to expand due to activation of the shape memory material. Medical devices can also expand due to other reasons, such as elastic recoil and/or thermal expansion. The methods and systems described herein may be used to limit the expansion of a medical device along at least one axis while inside a package. The methods and systems described herein may be used to relieve some of the stored strain in the medical device upon the opening of the package. Methods and systems are also described for opening a package which is subject to expansive forces from the medical device.

1 . A package for a medical device containing a shape memory polymer, the package comprising:
 at least one intermediate member which has an interior surface capable of mating with a portion of the medical device;   a constraining member disposed around the at least one intermediate member; and   a compressing member disposed between the at least one intermediate member and the constraining member.   
   
   
       2 . The package of  claim 1 , wherein a first contact area between the constraining member and the compressing member comprises between about  10  percent and about  40  percent of a second contact area between the constraining member the at least one intermediate member. 
   
   
       3 . The package of  claim 1 , wherein the compressing member comprises an annular element with a grove. 
   
   
       4 . The package of  claim 3 , wherein at least one of the intermediate members comprises a ridge, and wherein the ridge is at least partially disposed within the grove of the annular element. 
   
   
       5 . The package of  claim 3 , further comprising:
 a keystone element disposed within the grove of the annular element.   
   
   
       6 . The package of  claim 5 , wherein the grove of the annular element is displaced by the keystone element. 
   
   
       7 . The package of  claim 1 , wherein the at least one intermediate member is a sabot. 
   
   
       8 . The package of  claim 1 , wherein the at least one intermediate member is held in a desired configuration by the constraining member. 
   
   
       9 . The package of  claim 8 , wherein the at least one intermediate member further comprises:
 a plurality of intermediate members, with a plurality of interior surfaces which define a cavity forming an impression of the medical device when the intermediate members are in the desired configuration.   
   
   
       10 . The package of  claim 9 , wherein the cavity completely encompasses the medical device. 
   
   
       11 . The package of  claim 9 , wherein the cavity encloses a circumference of the medical device. 
   
   
       12 . The package of  claim 11 , wherein the cavity has an opening. 
   
   
       13 . The package of  claim 12 , wherein the opening has an axis which is at an angle to an expected axis of expansion of the medical device. 
   
   
       14 . The package of  claim 13 , wherein the angle is about 45 degrees or greater. 
   
   
       15 . The package of  claim 9 , wherein the each of the plurality of intermediate members comprises a key section which allows the intermediate members to align in the desired configuration and which inhibits the intermediate members from aligning in a configuration different from the desired configuration. 
   
   
       16 . The package of  claim 15 , wherein the each of the key sections is enclosed by the constraining member. 
   
   
       17 . The package of  claim 16 , wherein each of the plurality of intermediate members comprises a mating surface adapted to mate with a neighboring intermediate member of the plurality of intermediate members. 
   
   
       18 . The package of  claim 17 , wherein a guide pin is disposed on at least one mating surface of at least one of the plurality of intermediate members, and wherein the guide pin is disposed to mate with a guide hole of a neighboring intermediate member of the plurality of intermediate members when the plurality of intermediate members is in the desired configuration. 
   
   
       19 . A method of packaging a shape memory medical device, the method comprising:
 packaging a shape memory medical device in a chamber created by interior surfaces of a plurality of sabots;   encompassing a circumference of the plurality of sabots with a constraining member;   initiating an expansion of the medical device; and   limiting the expansion of the medical device via limiting movement of the sabots.   
   
   
       20 . The method of  claim 19 , wherein the expansion is due to an elastic recoil of the shape memory medical device. 
   
   
       21 . The method of  claim 19 , wherein the expansion is due to a recovery of the shape memory medical device. 
   
   
       22 . A removal device for removing a medical device from a package, the removal device comprising:
 a housing for containing the package in an unopened state, wherein the housing comprises a handle body and a hinged lid body attached to the handle body;   a chamber defined by an interior surface of the handle body and the hinged lid body, the chamber adapted to contain the package in the unopened state;   a cylinder adapted to engage a constraining member of the package, wherein turning about the axis of the cylinder winds a removed portion of the constraining member of around the cylinder; and   an opening shaped to allow the medical device to pass out of the chamber.   
   
   
       23 . The removal device of  claim 22 , further comprising:
 a handle attached to the cylinder for rotating the cylinder about the axis of the cylinder.   
   
   
       24 . The removal device of  claim 22 , wherein the housing is adapted to hold the constraining member in a fixed position relative to the housing while the cylinder is rotated. 
   
   
       25 . The removal device of  claim 24 , wherein the cylinder is adapted to translate relative to the housing while the cylinder is rotated. 
   
   
       26 . The removal device of  claim 22 , wherein the housing is adapted to hold the axis of the cylinder in a fixed position relative to the housing while the cylinder is rotated. 
   
   
       27 . The removal device of  claim 26 , wherein the constraining member is adapted to translate relative to the housing while the cylinder is rotated. 
   
   
       28 . The removal device of  claim 22 , further comprising:
 an extraction element for removing the medical device from the chamber.   
   
   
       29 . The removal device of  claim 28 , wherein the extraction element comprises:
 a plunger for pushing the medical device out of the chamber.   
   
   
       30 . A package for a medical device containing a shape memory polymer, the package comprising:
 at least one intermediate member which has an interior surface capable of mating with a portion of the medical device; and   a means for constraining the at least one intermediate member, the means for constraining disposed around the at least one intermediate member.   
   
   
       31 . The package of  claim 30 , further comprising:
 a means for compressing the medical device disposed between the at least one intermediate member and the means for constraining the medical device.   
   
   
       32 . The package of  claim 31 , wherein the means for compressing the medical device includes a means of varying a compression of the medical device continuously through a range of compressions. 
   
   
       33 . The package of  claim 31 , wherein the means for compressing the medical device may be removed from the package to relieve at least a portion of the compression of the medical device. 
   
   
       34 . The package of  claim 31 , wherein the means for constraining the medical device is a metallic tube, and wherein the means for compressing comprises a plurality of polymer sabots.