Abstract: Methods and apparatus for determining the orientation and the position of an object in space with the assistance of a sensing instrument are provided. The sensing instrument is provided with a marking element. The orientation and position of the marking element is determinable by means of the navigation system. In order to be able to carry out a reliable determination of the position, even under confined conditions of access, the sensing instrument is adapted to be successively connected in a guided manner to the object for free rotation about two non-parallel, defined axes of rotation. The sensing instrument can be rotated about these axes of rotation, and the orientation and the position of the two defined axes of rotation in space and hence the orientation and the position of the object in space can be calculated from the resulting movement of the marking element during this rotation.

Abstract: An expandable and retrievable stent is disclosed herein. The stent includes an inner strut, a first traveling anchor movably attached to the inner strut and a second anchor secured to the inner strut. The stent further includes frame connected to the first traveling anchor and the second anchor wherein the frame has at least a radially compressed configuration and a radially expanded configuration. The stent may also include a generally cylindrical sleeve.

Abstract: A balloon catheter is provided which may be used to dilate hardened regions of stenosis. The balloon catheter is provided with dilation wires that may be extended so that the dilation wires are disposed adjacent an outer surface of the balloon during dilation. Thus, as the balloon is expanded, the dilation wires are squeezed between the balloon and the stenosed region to crack or breakup the stenosis. The dilation wires may also be retracted away from the balloon. Thus, the stenosed region may be dilated with the balloon without using the dilation wires if desired.