Flexible stent structure

Abstract

Luminal prostheses comprise adjacent expansible segments, typically serpentine ring segments joined by sigmoidal links. By properly orienting the sigmoidal links and aligning hinge regions on adjacent serpentine rings, enhanced opening characteristics can be obtained. Additionally, by varying the mechanical characteristics of adjacent serpentine rings, program expansion of the luminal prostheses over their lengths may be obtained. The disclosed prostheses also have controllable opening characteristics and can be crimped to small diameters.

1 . A radially expansible luminal prosthesis including a scaffold comprising: 
 a plurality of serpentine ring segments including struts connected by circumferentially offset hinge regions, each hinge region having an apex and side regions disposed on either side of the of the apex; and    links between at least some of the hinge regions on adjacent serpentine rings, wherein the links are attached on the sides of the hinge regions, and all links have substantially similar sigmoidal shapes.    
   
   
       2 . A radially expansible luminal prosthesis as in  claim 1 , wherein each sigmoidal link comprises two connecting legs and wherein each connecting leg is attached to a hinge region in a circumferential direction.  
   
   
       3 . A radially expansible luminal prosthesis as in  claim 2 , wherein each sigmoidal link has a uniform width over its length.  
   
   
       4 . A radially expansible luminal prosthesis as in  claim 2 , wherein each sigmoidal link has a flared end with joins to the hinge region.  
   
   
       5 . A radially expansible luminal prosthesis as in  claim 2 , wherein the sigmoidal link is adapted to permit the connecting legs to move circumferentially past each other to accommodate radial crimping of the prosthesis.  
   
   
       6 . A radially expansible luminal prosthesis as in  claim 1 , wherein the ring segments are expansible in response to a radially outward force; 
 wherein at least one of the ring segments opens at a different rate or in a different amount than at least one other ring segment when exposed to the same radially outward force.    
   
   
       7 . A radially expansible luminal prosthesis as in  claim 6 , wherein at least some struts in at least some of the serpentine rings have different lengths to cause a different rate or amount of expansion.  
   
   
       8 . A radially expansible luminal prosthesis as in  claim 7 , wherein at least some struts which are positioned away from the sigmoidal links are longer.  
   
   
       9 . A radially expansible luminal prosthesis as in  claim 6 , wherein at least some of the struts have different widths than others of the struts to cause a different rate or amount of expansion.  
   
   
       10 . A radially expansible luminal prosthesis as in  claim 6 , wherein at least some of the hinge regions have different widths than others of the hinges regions to cause a different rate or amount of expansion.  
   
   
       11 . A radially expansible luminal prosthesis as in  claim 1 , wherein at least some of the struts are straight over the distance between the hinges.  
   
   
       12 . A radially expansible luminal prosthesis as in  claim 1 , wherein at least some of the struts are non-linear.  
   
   
       13 . A radially expansible luminal prosthesis as in  claim 1 , wherein the sigmoidal links are individually axially expansible and contractable.  
   
   
       14 . A radially expansible luminal prosthesis including a scaffold comprising: 
 a plurality of serpentine ring segments including struts connected by hinge regions being circumferentially offset with apices and side regions disposed on either side of the apices; and    links extending between and connecting at least some of the hinge regions on adjacent serpentine rings, wherein each link is attached on a side of each connected hinge region and wherein all the links have substantially similar sigmoidal shapes.    
   
   
       15 . A radially expansible luminal prosthesis as in  claim 14 , wherein the connected hinge regions on adjacent serpentine rings are axially proximate one another.  
   
   
       16 . A radially expansible luminal prosthesis as in  claim 14 , wherein less than all of the hinge regions of a serpentine ring are connected to hinge regions of an adjacent serpentine ring.  
   
   
       17 . A radially expansible luminal prosthesis as in  claim 14 , wherein all of the hinge regions of a serpentine ring are connected to hinge regions of an adjacent serpentine ring.  
   
   
       18 . A radially expansible luminal prosthesis as in  claim 14 , wherein a number of the connected hinge regions of the serpentine rings is constant along the length of the prosthesis.  
   
   
       19 . A radially expansible luminal prosthesis as in  claim 14 , wherein a number of the connected hinge regions of the serpentine rings varies along the length of the prosthesis.  
   
   
       20 . A radially expansible luminal prosthesis including a scaffold comprising: 
 a plurality of serpentine ring segments including struts connected by hinge regions having apices and side regions, wherein the side regions are disposed on either side of the of the apices; and    links between at least some of the hinge regions on adjacent serpentine rings, wherein the links are attached on the sides of the hinge regions and all links have substantially similar sigmoidal shapes.    
   
   
       21 . A radially expansible luminal prosthesis as in  claim 20 , wherein opposed hinge regions on adjacent serpentine rings are circumferentially offset.  
   
   
       22 . A radially expansible luminal prosthesis including a scaffold comprising: 
 a plurality of serpentine ring segments including struts and hinge regions disposed between the struts, each hinge region having an apex and side regions disposed on either side of the apex;    links extending from one of the side regions of at least some of the hinge regions and connecting at least some of the adjacent serpentine rings, wherein all links have substantially similar sigmoidal shapes; and    cells formed by a boundary defined by adjacently joined serpentine ring segments and a pair of radially adjacent links connecting the adjacent serpentine rings, wherein each cell has a shape which is a multiple of the smallest cell.    
   
   
       23 . A radially expansible luminal prosthesis as in  claim 22 , wherein each cell has a substantially similar shape.