Needle assembly and blade assembly for biopsy device

A biopsy blade assembly comprising:

• (a) a blade comprising:
• (i) a first cutting edge,
• (ii) a second cutting edge,
• (iii) a distal end, wherein the distal end terminates in a point formed by the intersection of the first cutting edge and the second cutting edge, and
• (iv) a retention channel passing laterally through the blade from a first exterior blade surface to a second exterior blade surface, wherein the first exterior blade surface and the second exterior blade surface are laterally offset from each other;
• and
• (b) a multi-member coupling assembly having a proximal end, wherein the multi-member coupling assembly comprises a first coupling member and a second coupling member, wherein the multi-member coupling assembly is configured to couple about the blade such that the first coupling member engages the first exterior blade surface and the second coupling member engages the second exterior blade surface and such that a portion of the multi-member coupling assembly extends laterally through the retention channel of the blade, and wherein the proximal end of the multi-member coupling assembly is configured to couple to a distal end of a biopsy device.

A biopsy device comprising:

• (a) a probe assembly;
• and
• (b) a needle assembly extending distally from the probe assembly, the needle assembly comprising:
• (i) a needle portion having a distal end;
• and
• (ii) a blade assembly comprising:
• (1) a multi-member coupling assembly configured to couple to the distal end of the needle portion, wherein the multi-member coupling assembly comprises a first piece defining a first conical surface and a second piece defining a second conical surface, and
• (2) a blade, wherein the blade defines a retention channel, wherein the blade is positioned between the first piece and the second piece of the multi-member coupling assembly such that the first conical surface and the second conical surface are laterally offset relative to the retention channel, wherein the blade extends distally from the multi-member coupling assembly, and wherein the blade comprises a first cutting edge and a second cutting edge, wherein the first cutting edge and the second cutting edge each continuously extend distally until the first cutting edge and the second cutting edge converge to form a point.