Patent ID: 7569065
Filing Date: 2009-08-04
Classification: A61B,A61M

Abstract:
1. A marking apparatus for the percutaneous placement of an imaging marker at a location in a tissue mass to facilitate subsequent determination of the location of the tissue mass, the marking apparatus comprising: a handle defining a hollow interior; a cannula extending from the handle and defining a lumen open to the hollow interior of the handle, a distal end of the cannula forming an insertion tip with an axial opening at the insertion tip; a stylet having a proximal end with a proximal tip and a distal end, slidably received within the lumen for movement between a ready position and an extended position, where, in the ready position, the proximal tip is disposed in the handle and the distal end of the stylet is spaced inwardly from the insertion tip to define a marker recess between the distal end of the stylet and the axial opening, and in the extended position the distal end of the stylet extends at least into the marker recess; an imaging marker disposed within the marker recess to be expelled through the axial opening by movement of the stylet from the ready position to the extended position, wherein the imaging marker has no lead long enough to extend from the interior of the tissue mass to the exterior of the tissue mass when the imaging marker has been placed in the tissue mass; an actuator for effecting the relative movement of the cannula and the stylet to move the stylet from the ready to the extended position; and a latch for fixing the stylet in the extended position to prevent the retraction of the stylet from the extended position; whereby a user can place the imaging marker with one hand by grasping the handle to effect the insertion of the cannula into the tissue mass, expelling the imaging marker into the tissue mass by moving the stylet to the extended position, and removing the cannula from the tissue mass after the expulsion of the imaging marker, leaving the imaging marker in the tissue mass with no lead extending from the interior of the tissue mass to the exterior of the tissue mass; wherein the actuator comprises a plunger slidably mounted to the handle and mounting the stylet such that the relative sliding movement of the plunger and handle between first and second positions causes a corresponding relative sliding movement of the stylet and cannula to move the stylet and cannula between the ready and extended positions; wherein the latch comprises a detent on one of the plunger and the handle and a catch on the other of the plunger and the handle, the catch being receivable within the detent as the plunger is moved from the first to the second position; wherein the handle has an inner surface forming the hollow interior and defining an open end, the plunger being slidably received within the handle hollow interior through the open end, the detent comprising a recess formed in the handle inner surface, and the catch comprising a protuberance extending from the plunger; and wherein the detent recess is spaced from the open end and the handle further comprises a groove extending from the open end to the detent recess and is sized to receive the protuberance, whereby when the plunger is moved from the first to second position, the protuberance is slidably guided within the groove to the detent recess.