A graftless prosthetic stent for treatment of vascular lesions such as aneurysms
and arterio-venous fistulas, especially in neurovascular vessels, comprises a continuous
helical ribbon formed of a shape-retaining metal having a transition temperature
at which the stent expands from its contracted condition to a radially expanded
condition, the stent remaining substantially cylindrical in its contracted and
expanded conditions. The helical windings have variable width, thickness, number
or size of openings, or combinations of these features, which affect the stiffness,
rate of expansion at the transition temperature, and the area of vessel wall covered
by the stent. A catheter device which includes the stent, and a method of treatment
using the stent are also provided.
