Patent ID: 7390306
Filing Date: 2008-06-24
Classification: A61B

Abstract:
1. A needle set for a biopsy device, comprising: an outer member having a tip member having a working end, an opposite end and a tip lumen defined therebetween; a cylinder portion having a first end hermetically connected to said opposite end of said tip member, a second end and a cylinder lumen defined therebetween, said cylinder lumen in fluid communication with said tip lumen; a hub member defining a hub lumen in fluid communication with said cylinder lumen, said hub lumen in fluid communication with a pair of openings defined in opposite sides of said hub member; said second end of said cylinder attached to said hub member at one of said opposite sides of said hub member and positioned so that said cylinder lumen is aligned with said hub lumen; and a cylinder seal member positioned within said cylinder lumen and fixed to an interior surface of said cylinder, said cylinder seal member defining an opening therethrough in communication with said cylinder lumen, and a vent seal disposed within said hub lumen; and an inner member having a cannula slidably disposed within said cylinder lumen and through said opening of said cylinder seal member and having a proximal end and a distal end with an inner lumen defined therebetween, said cannula further defining a vent aperture adjacent said proximal end of said cannula; a sampling portion attached to said distal end of said cannula, said sampling portion defining a sampling cavity; a cannula seal member fixed to an outer surface of said cannula proximal to said sampling portion, said cannula seal member configured to movably seal within said cylinder lumen; wherein the cannula includes an opening that is disposed between said cylinder seal member and said cannula seal member; wherein at least said cannula seal member and said cylinder seal member cooperate to define a vacuum chamber; and wherein said inner member and said outer member are movable relative to one another between wherein the generated vacuum selectively increases at the tissue site generally proportionally to the distance that said cannula seal member is moved away from said cylinder seal member; and wherein said needle set is operable to be placed in a cocked position with said vent aperture exposed to vent air from the inner lumen as the cannula is moved to the extended position, said vent aperture being sealed by said vent seal when said cannula is in the extended position.