Patent ID: 8167903

Claim:
A retrieval device for entrapping and retaining a foreign object located in a body vessel for its extraction therefrom, the device comprising: a cage having a proximal end and a distal end and a longitudinal axis extending between the proximal and distal ends, the cage including: a plurality of longitudinal bars extending an entire length of the cage and between the proximal and distal ends, the longitudinal bars forming a cylindrical portion in an expanded state, the cylindrical portion defining a cylinder volume; and a plurality of struts connecting adjacent longitudinal bars, each strut having two ends adjoining the adjacent longitudinal bars and a pivotal joint disposed between the two ends, each strut extending proximally from the two ends to the pivotal joint to define a “V” shape in the expanded state, each strut being biased inwardly toward the longitudinal axis such that the pivotal joint is disposed within the cylinder volume in the expanded state to facilitate retaining the foreign object within the cage, the pivotal joints unfolding to move the longitudinal bars radially outward from the longitudinal axis, radially expanding the cage about the longitudinal axis to define the expanded state and forming an opening at the distal end for receiving the foreign object, and the pivotal joints folding to collapse the longitudinal bars along the longitudinal axis, collapsing the cage to define a collapsed state and to retain the foreign object therein such that the foreign object is substantially aligned with the longitudinal axis, the plurality of struts comprising a distal plurality of struts and a proximal plurality of struts, the distal plurality of struts forming a distal ring connected to each of the longitudinal bars and forming the distal end of the cage, the proximal plurality of struts forming a proximal ring connected to each of the longitudinal bars along the cylindrical portion and spaced apart from the distal ring, the longitudinal axis extending through a central point of the proximal ring and through a central point of the distal ring; and a cable extending proximally from the proximal end of the cage for retrieval of the device in the collapsed state, wherein the pivotal joints of the distal plurality of struts point toward the cable.