Patent ID: 8152820

Claim:
A device for extracting a mass from a patient's body, the device comprising: a coaxial tube assembly including an inner tube and an outer tube that are coaxially arranged and that define a proximal end and a distal end that is positionable within the body when the proximal end is positioned outside of the body, wherein the inner tube defines a lumen and the outer tube cooperates with the inner tube to define a coaxial annular space; a bag that receives therein the mass to be extracted; a bag-translating assembly including a coupling and a lead-screw mechanism, wherein the coupling couples to the bag and translates within the annular space of the coaxial tube assembly to move the bag from a deployed position within the body, through a retracting motion, and to a retracted position within the annular space, wherein as the bag is moved through the retracting motion the mass in the bag is pulled at least partially into the lumen at the distal end of the coaxial tube assembly, and wherein the lead-screw mechanism includes mating screw threads on an inner surface of the coupling and on an outer surface of the inner tube and includes conforming non-circular profiles defined by an outer surface of the coupling and an inner surface of the outer tube so that, upon application of a rotary force to the inner tube, the coupling is constrained by the conforming non-circular profiles from rotational movement relative to the outer tube and the rotationally constrained coupling translates along the inner tube impelled by the relative rotation of the mating screw threads; and a drive assembly including at least one actuator that is adapted to activate the bag-translating assembly to move the bag from the deployed position to the retracted position.