초록 ▼

The present invention is directed to a biopsy needle for extracting bone marrow from a living bone. The biopsy needle comprises an outer cannula, an inner cannula slidable therein, an obturator and an ejector rod. The outer cannula has a proximal end, affixed to a handle, and a distal end which has

The present invention is directed to a biopsy needle for extracting bone marrow from a living bone. The biopsy needle comprises an outer cannula, an inner cannula slidable therein, an obturator and an ejector rod. The outer cannula has a proximal end, affixed to a handle, and a distal end which has a tapered inner diameter. The inner cannula likewise has a proximal end, affixed to an interlocking handle, and a distal end. The inner cannula distal ends consists of a tissue receiving region and a tissue grasping mechanism. The tissue grasping mechanism comprises a resilient deformable wall with an asymmetric configuration, preferably, two opposing slits, and a structure-maintaining spanning member. The tissue grasping member is which are deformed and at least partially closed upon insertion into the tapered region of the outer cannula. In operation, this deformation severs a tissue sample into the receiving region of the inner cannula, which may then be withdrawn from a patient. A spring biased ejector rod displaces the sample from the inner cannula, while also reforming the tissue grasping portion of the inner cannula to its original pre-biopsy shape. The obturator may be used in combination with the outer cannula for initial insertion of the needle into the patient.

대표청구항 ▼

[ What is claimed is:] [1.] A bone marrow biopsy device for insertion into and through a mass of bone to retrieve a biopsy sample of bone marrow tissue, said bone marrow biopsy device comprising:an outer cannula, said outer cannula having a proximal end, a distal cutting end and a substantially holl

[ What is claimed is:] [1.] A bone marrow biopsy device for insertion into and through a mass of bone to retrieve a biopsy sample of bone marrow tissue, said bone marrow biopsy device comprising:an outer cannula, said outer cannula having a proximal end, a distal cutting end and a substantially hollow cross-section between said proximal and distal ends, said substantially hollow cross-section having a predetermined inner diameter that tapers inwardly proximate said distal end to form a tissue engaging region within said distal end;an inner cannula operably slidable within said hollow cross-section of said outer cannula, said inner cannula having a proximal end, a distal end and a substantially hollow tissue receiving portion proximate said inner cannula distal end for retrieving at least a portion of a tissue sample from within the tissue engaging region of said outer cannula,said inner cannula having a predetermined outer diameter slightly narrower than said predetermined inner diameter of said outer cannula except at said tissue engaging region where said tapered distal end of said outer cannula is of a diameter less than that of said inner cannula prior to deformation of said inner cannula distal end by said outer cannula distal end,said tissue receiving portion of the inner cannula distal end further having both a continuity of structure and a malleable memory; andat least two or more interruptions in the continuity of the structure of the tissue receiving portion of the inner cannula, at least two of said two or more interruptions being different from each other in at least one of configuration and orientation to alter the malleable memory of said tissue receiving portion of the distal end of said inner cannula and to define a tissue grasping member that constricts upon said deformation of said inner cannula distal end,said tissue grasping member of said inner cannula constricting within the distal end of said outer cannula to, in turn, grasp a tissue sample positioned therewithin, upon operable engagement between the inwardly tapered tissue engaging region of said outer cannula and the tissue grasping member of said inner cannula.