The colon and duodenal stents make use of two fundamentally different stent production technologies:

“S”:
Fixed, braided stent structure consisting of one nitinol wire that is braided into a tube shape. This gives the stent its characteristic form through the memory effect, and it reassumes this shape every time it is deformed.

“D”:
In contrast to the “S” sent, in a “D” stent two nitinol wires are braided together. This allows the stent to maintain its form at a defined radial strength through the memory effect in the radial direction. It can be retracted in the axial direction to bend while the stent maintains its form. This provides an ideal balance of radial strength and flexibility, and is an advantage particularly if the stent needs to be placed in tortuous anatomy.