Bone marrow biopsy needle

A snare coil type biopsy needle that includes an actuatable snare for removal of tissue from a patient comprising:

• an outer tube having a distal end;
• and
• an inner tube disposed partially within said outer tube for actuating the snare, the snare contained within the outer tube;
• wherein a distal section of the inner tube extends beyond a distal section of the outer tube and defines the distalmost end of the needle, the needle having a tip transition region that is defined by the distal section of the inner tube and the distal section of the outer tube that is adjacent the distal section of the inner tube that extends beyond the outer tube and defines a distal end of the needle, the outer tube having a second region that is proximal to and adjacent the distal section of the outer tube, wherein the tip transition region, defined by the distal sections of the inner and outer tubes, has a frustoconically shaped outer surface that defines a surface area (A), the tip transition region being located between the distal end of the needle and an interface between the distal section of the outer tube and the second region of the outer tube, wherein a circular shaped area (Ba) comprises an area transecting the needle perpendicular to the longitudinal axis of the needle at a location where the distal section of the outer tube interfaces with the second region, the interface being defined where a degree of taper of the outer tube changes, the interface further representing a base of the frustoconically shaped tip transition region defined by a diameter of the outer tube and wherein a ratio R=(A)/(Ba) is approximately 1 for an 8 gauge needle and is approximately 1.2 for an 11 gauge needle.