Stent

摘要

An expandable stent that can be used in an artery or any other vessel of the human body forms a multiplicity of generally circular rings when expanded and provides a closed structure which optimizes hoop strength so as to minimize elastic recoil of the vessel into which the stent is inserted. The structure of the stent is initially in the form of folded ellipses or ovals which can be formed to a small diameter for percutaneous insertion by means of a stent delivery catheter. The ovals are joined to each other by either a straight or undulating shaped wires which are called "longitudinals" which serve to space the deployed rings within the vessel. Straight longitudinals are used in straight vessels and undulating longitudinals can be employed in either straight or highly curved vessels such as some coronary arteries.