Patent ID: 7577473

Claim:
A subcutaneous marking apparatus for placement of an imaging marker at a predetermined site in a tissue mass to facilitate subsequent determination of the predetermined site, the marking apparatus comprising: a handle having a front portion and a rear portion located behind the front portion, with the rear portion having a length such that a user can grasp the handle between multiple fingers and a palm or a thumb of one hand; a cannula defining a lumen and having a proximal end mounted to the handle and a distal end defining a tip; a stylet slidably received within the lumen for movement between a ready position in which a distal end of the stylet is spaced inwardly from the tip to form a marker recess between the distal end of the stylet and the tip, and an extended position in which the distal end of the stylet is advanced toward the tip and into the marker recess; a trigger extending through a side surface of the front portion of the handle, in a direction substantially perpendicular to an axis of the cannula, and operably engaging the stylet, the trigger being operable between a first position and a second position for moving the stylet between the ready position and the extended position; and an imaging marker disposed within the marker recess; wherein at least a first portion of the trigger is moved downwardly in a direction substantially perpendicular to the axis of the cannula to release the trigger for movement from the first position to the second position; and wherein the marking apparatus can place the imaging marker at the predetermined site by the user actuating the trigger between the first and second positions with either an index finger or the thumb of the one hand while holding the handle between either the fingers and the thumb or the fingers and the palm to move the stylet from the ready position to the extended position to thereby eject the imaging marker from the marker recess after the tip of the cannula is located at the predetermined site.