Soft tissue core biopsy instrument

Abstract

The soft tissue core biopsy instrument comprises a proximal outer barrel member having a distal end and a proximal end; a distal inner barrel member which is slidably received within said outer barrel member, which has a distal end and a proximal end and which has a stop in said distal end; a cannula driver in said inner barrel member; a cannula extending distally from said inner barrel member, being fixed to said cannula driver, and having a distal tip, said cannula driver being slidably received in and movable within said inner barrel member and said cannula extending a predetermined distance out of a distal end of said inner barrel member when the instrument is in an at-rest condition; a stylet having a distal end, a proximal end, and being removably received in said outer barrel, in said inner barrel, and in said cannula, said distal end having a biopsy sample receiving notch therein; a stylet hub mounted to said proximal end of said stylet; said stylet hub being removably attached to the proximal end of said proximal outer barrel member to enable multiple biposies to be obtained with one insertion of said cannula, said stylet extending distally from said hub and within said cannula and having a distal tip portion (a) positioned within said cannula when the instrument is in an at-rest position and (b) extending distally of said distal tip of said cannula in position to capture a biopsy sample when the instrument is in a cocked condition; biasing means within said inner barrel member between said stop and said cannula driver for biasing said cannula driver; latching means associated with said cannula driver and said inner barrel member for latching said cannula driver in a proximally retracted cocked position within said outer barrel member and said inner barrel member against the biasing action of said biasing means; and a trigger, associated with said latching means, for unlatching said latching means, said trigger, upon being actuated for unlatching of said latching means, allowing said biasing means to quickly return said cannula driver and said cannula to said distally extending position thereof and over said stylet distal tip portion.