Patent ID: 6428486
Filing Date: 2002-08-06
Classification: A61B

Abstract:
A biopsy instrument, comprising:an elongate hollow outer piercing needle having a lumen, a sharpened distal end for piercing tissue, and a lateral opening located proximal to said sharpened distal end for receiving a portion of a tissue mass positioned adjacent to said lateral opening; an elongate inner cutting cannula having a lumen and being disposed coaxially and slidable within said elongate outer piercing needle, said elongate inner cannula having a sharpened distal end for cutting the portion of tissue protruding into said elongate outer piercing needle lateral opening when said elongate inner cannula slides distally past said lateral opening, thereby depositing the portion of cut tissue within said elongate inner cannula proximal to said sharpened distal end; a vacuum generator for generating a vacuum pressure which fluidly communicates with said lateral opening through said inner cannula lumen; and a tissue stop device disposed in the lumen of said inner cannula and having a structure disposed proximally of said lateral opening which is adapted to sufficiently obstruct said lumen so that a tissue sample drawn into the lateral opening by said vacuum pressure and severed by the cutting cannula is prevented from migrating proximally through the cutting cannula lumen.