Patent ID: 8882827

Claim:
A stent comprising a tubular body comprising a plurality of ring units being arranged in a longitudinal axis direction and bridged by a connecting element, each of the ring units comprising a plurality of cells connected with each other, each of the cells having a substantially U-shaped form, comprising two substantially linear parts and a substantially circular arc part between the substantially linear parts, and opening toward one end along the longitudinal axis direction, the tubular body being capable of expanding in the radius direction from its inside, wherein the ring units comprise a first ring unit and a second ring unit, the first ring unit and the second ring unit being alternatively arranged so that the central axis of the stent is surrounded, the first ring unit comprising a first cell group in which a plurality of first cells are connected with each other in the circumferential direction, the second ring unit comprising a second cell group in which a plurality of second cells are connected with each other in the circumferential direction, and the first cells in the first ring unit being disposed oppositely to the second cells in the second ring unit adjacent to the first ring unit to form pairs of oppositely disposed first and second cells; the shapes of the first and second cells are axisymmetrical of the stent about the connecting element; only a portion of the pairs of the oppositely disposed first and second cells are bridged by the connecting element, such that a remaining portion of the pairs are unbridged, the connecting element creating a connection between the substantially circular arc parts of the oppositely disposed cells; the curvature radius of the top of the arc constituting the substantially circular arc part of the cells in substantially all of the cells constituting the stent, is 1.1 to 1.5 times larger than the curvature radius of each of the tangent circles formed at the edges of the two substantially linear parts of the cell on the circular arc part side; the substantially linear parts of the cells bridged by the connecting element have the same length with each other, and the substantially linear parts of the cells bridged by the connecting element are longer than the substantially linear parts of the unbridged cells by 10 to 25%; and the bridged pairs of oppositely disposed first and second cells are bridged directly and have overlapped vertexes of the circular arc parts of the oppositely disposed cells with a constant thickness and width to form the connecting element.