Biopsy needle

Claim 1

An elongate hollow biopsy needle having opened distal and proximal ends, said distal end defining a cutting edge, said needle being of uniform hollow cylindrical configuration throughout the major portion of its length, and having an external distal end surface portion tapered generally uniformly, uninterrupted, toward the tip of the distal end, and an internal end surface defining an inner biopsy tissue receiving and retaining bore immediately adjacent the distal end and with the needle converging from a first circular diameter which extends along the major portion of the length of the needle toward and to a second and significantly smaller circular diameter at the distal end, an elongate stylet positioned within said needle and corresponding generally in length and shape to the bore formed in said needle, said stylet being of uniformly cylindrical configuration throughout a major portion of its length, and having a uniformly uninterrupted tapered distal end portion converging to a closed distal end tip; means arranged on said needle and stylet to position the stylet within said needle so that the distal ends of the needle and stylet cooperate with each other to present a symmetrical closed tip end whereby said needle and stylet may be inserted as a unit into a tissue, and when said stylet is removed from the needle after insertion into a tissue, and upon manipulation of the needle, the distal cutting end of the needle will cut a tissue sample and the tissue sample will be collected in the expanded distal end portion of the bore of the needle to thereby minimize damage to the tissue.