Self-contained, self-piercing, side-expelling marking apparatus

Abstract

A marking apparatus includes a rigid cannula having a peripheral wall forming a lumen that carries an imaging marker, a proximal end coupled to a handle, a lateral opening in the peripheral wall that is open to the lumen, and a closed-off distal portion having a ramp adjacent the lumen. The closed-off distal portion extends distally from the ramp to terminate at a tissue piercing pointed tip. The ramp of the rigid cannula is curved to transition from the peripheral wall of the rigid cannula to the lateral opening of the rigid cannula. The ramp of the rigid cannula is adapted to engage the distal end of the stylet as the stylet is advanced through the lumen of the rigid cannula to guide the distal end of the stylet to a position to substantially close off the lateral opening of the rigid cannula having the tissue piercing tip.

1 . A marking apparatus for the percutaneous placement of an imaging marker in a tissue mass, the marking apparatus comprising:
 a handle to be grasped by a user;   a rigid cannula having:
 a peripheral wall forming a lumen that carries the imaging marker, 
 a proximal end coupled to the handle, 
 a lateral opening in the peripheral wall that is open to the lumen, and 
 a closed-off distal portion having a ramp adjacent the lumen, the closed-off distal portion extending distally from the ramp to terminate at a tissue piercing pointed tip, the ramp of the rigid cannula being curved to transition from the peripheral wall of the rigid cannula to the lateral opening of the rigid cannula; and 
   a stylet having a distal end, with at least the distal end of the stylet being flexible, the stylet being slidably received within the lumen of the rigid cannula for movement in the lumen, the ramp of the rigid cannula being adapted to engage the distal end of the stylet as the stylet is advanced through the lumen of the rigid cannula to guide the distal end of the stylet to a position to substantially close off the lateral opening of the rigid cannula having the tissue piercing tip.   
     
     
         2 . The marking apparatus of  claim 1 , wherein only the distal end of the stylet closes off the lateral opening. 
     
     
         3 . The marking apparatus of  claim 1 , wherein the stylet received in the lumen has a ready position, where the distal end of the stylet is spaced inwardly from the closed-off distal portion to form a marker recess that is in communication with the lateral opening and that is sized to receive the imaging marker, and an expelled position, where the distal end of the stylet is advanced a sufficient distance into the marker recess to expel the imaging marker contained in the lumen of the rigid cannula through the lateral opening, and the ramp being adapted to engage the distal end of the stylet and guide the distal end of the stylet into the lateral opening to substantially close off the lateral opening of the rigid cannula after the imaging marker is expelled. 
     
     
         4 . The marking apparatus of  claim 3 , and further comprising multiple imaging markers contained within the marker recess. 
     
     
         5 . The marking apparatus of  claim 1 , wherein the rigid cannula is 13 gage or less. 
     
     
         6 . The marking apparatus of  claim 1 , wherein the handle, the rigid cannula, and the stylet are operably coupled to form a self-contained marking apparatus. 
     
     
         7 . A marking apparatus for the percutaneous placement of an imaging marker in a tissue mass, comprising:
 a handle to be grasped by a user;   a cannula having:
 a peripheral wall forming a lumen that carries the imaging marker, 
 a proximal end coupled to the handle, 
 a lateral opening in the peripheral wall that is open to the lumen, and 
 a closed-off distal portion having a ramp adjacent the lumen, the closed-off distal portion extending distally from the ramp to terminate at a tissue piercing pointed tip; and 
   a stylet having a distal end with an angled surface, the stylet being disposed in the lumen and movable in the lumen between a ready position and an expelled position, such that when the stylet is advanced through the lumen to the expelled position the ramp deflects the distal end of the stylet toward the lateral opening such that at the expelled position the angled surface is flush with the peripheral wall of the cannula at the lateral opening of the cannula.   
     
     
         8 . The marking apparatus of  claim 7 , wherein the angled surface of the distal end of the stylet closes off the lateral opening. 
     
     
         9 . A marking apparatus for the percutaneous placement of an imaging marker in a tissue mass, the marking apparatus comprising:
 a handle to be grasped by a user;   a cannula having:
 a peripheral wall forming a lumen that carries the imaging marker, 
 a proximal end carried by the handle, 
 a closed-off distal portion terminating in a self-piercing tip, 
 a ramp integrated with the closed-off distal portion, and 
 a lateral opening in the peripheral wall, wherein the lateral opening extends in a region between the proximal end and the closed-off distal portion of the cannula, the lateral opening having a proximal extent and a distal extent, the distal extent being closer to the self-piercing tip than the proximal extent; and 
   a stylet that includes a distal end, the stylet being slidably received within the lumen for movement between a ready position, wherein the distal end of the stylet is spaced inwardly from the self-piercing tip to form a marker recess in communication with the lateral opening, and an expelled position, wherein the distal end of the stylet is advanced a sufficient distance into the marker recess to expel the imaging marker contained in the lumen through the lateral opening of the cannula;   wherein when the distal end of the stylet is at the expelled position the distal end of the stylet is deflected by the ramp to close off the lateral opening of the cannula between the proximal extent and the distal extent of the lateral opening.   
     
     
         10 . The marking apparatus of  claim 9 , wherein a portion of the stylet including the distal end is formed of a flexible material and includes an angled surface, the angled surface being configured to close the lateral opening in the cannula between the proximal extent and the distal extent of the lateral opening when the stylet is in the expelled position. 
     
     
         11 . The marking apparatus of  claim 9 , wherein a portion of the stylet including the distal end is formed of a flexible material and includes an angled surface, the angled surface being flush with the peripheral wall of the cannula at the lateral opening in the cannula when the stylet is in the expelled position.