Stent with flexible hinges
A helical stent includes at least one helical winding. Each helical winding includes a plurality of alternating long struts and short struts, ends of at least some of the long struts being joined to an end of an adjacent short strut by a flexible hinge arrangement, the struts being substantially rigid. The stent also includes at least one interconnection member connecting a hinge arrangement on one turn of the at least one winding with a hinge arrangement on an adjacent turn of the at least one winding. Fewer than all hinge arrangements on the at least one helical winding are connected to other hinge arrangements by an interconnection member.
1 . An expandable stent comprising:
a plurality of expandable cells having at least eight sides and formed by a plurality of alternating long and short, substantially non-deforming struts interconnected by deformable hinges.
2 . The expandable stent as set forth in claim 1 , wherein the cells are interconnected to form a cylindrical shape.
3 . The expandable stent as set forth in claim 2 , wherein the cells having long axes that extend generally helically around the stent.
4 . The expandable stent as set forth in claim 1 , wherein, when the cells are expanded, the hinges deform and the struts are not substantially deformed.
5 . The expandable stent as set forth in claim 1 , wherein the cells have sixteen sides.
6 . The expandable stent as set forth in claim 1 , wherein the alternating long and short struts and connecting hinges define a plurality of successive cells defining a generally helical shape.
7 . The expandable stent as set forth in claim 1 , further comprising at least one opening for receiving a drug in at least one of the long and short struts.
8 . The expandable stent as set forth in claim 1 , comprising a substantially rigid interconnection member to which deformable hinges are connected at each of two opposite ends of the cell.
9 . The expandable stent as set forth in claim 8 , comprising at least one opening for receiving a drug in at least one of the long and short struts and the interconnection members.
10 . The expandable stent as set forth in claim 8 , further comprising one or more additional interconnection members located at non-adjacent struts on one or more sides of the cell.
11 . The expandable stent as set forth in claim 5 , wherein the sixteen sided cells are formed by four long and four short struts arranged in a first Z-shaped pattern and four long and four short struts arranged in a second Z-shaped pattern, with the first and second Z-shaped patterns attached to each other at opposite ends by connection of a long strut to a short strut.
12 . The expandable stent as set forth in claim 11 , wherein the connection between the first and second Z-shaped patterns is a substantially rigid interconnection member to which deformable hinges are connected.
13 . The expandable stent as set forth in claim 11 , wherein the cells have long axes which extend between the first and second Z-shaped patterns and cross at the opposite ends.
14 . The expandable stent as set forth in claim 13 , wherein the long axes extend generally helically around the stent.
15 . The expandable stent as set forth in claim 13 , wherein the long axes extend at an angle of about 60° to about 80° with respect to a longitudinal axis of the stent.
16 . The expandable stent as set forth in claim 1 , wherein the deformable hinges have a width and the widths of the hinges are varied to achieve uniform opening of the stent.
17 . The expandable stent as set forth in claim 16 , wherein there are at least three different hinge widths located in an asymmetric pattern within the expandable stent.