Biopsy sample retention mechanism

1. An apparatus comprising:

a biopsy needle having a distal end and a proximal end, all or a portion of the biopsy needle being movable between a collapsed state and an expanded state;

a sheath having a distal end and a proximal end,

wherein the biopsy needle in the collapsed state is contained within the sheath, and in the expanded state at least the distal end of the biopsy needle extends from the distal end of the sheath;

wherein the biopsy needle is provided with two or more sleeves, which at least partially overlap in the collapsed state and which cylindrically expand to provide an increased radius, relative to a radius in the collapsed state, for sampling in the expanded state;

wherein a cross section of the distal end of the biopsy needle in the expanded state is a substantially circular cross section; and

wherein an entire length of the needle is the two or more sleeves.

2. The apparatus of claim 1 , wherein a distal most edge of the needle is a chamfered edge.

3. The apparatus of claim 2 , wherein the two or more sleeves are the distal end of the needle.

4. The apparatus of claim 1 , wherein the two or more sleeves are the distal end of the needle.

5. The apparatus of claim 4 , wherein the two or more sleeves are connected to a shaft of the needle.

6. The apparatus of claim 1 , wherein the two or more sleeves are generally cone shaped when in the expanded state.

7. The apparatus of claim 1 , wherein a sample core which is collected becomes elongated when the biopsy needle is returned to a collapsed state within the sheath.

8. The apparatus of claim 7 , wherein the two or more sleeves are generally cone shaped when in the expanded state.

9. The apparatus of claim 1 , wherein an inside surface of the two or more sleeves is provided with retaining mechanisms which extend toward a center of the biopsy needle.

10. The apparatus of claim 1 , wherein an inside surface of the two or more sleeves is provided with retaining mechanisms which extend toward the proximal end of the biopsy needle.

11. The apparatus of claim 1 , wherein a rotating mechanism rotates about the rotational axis as the biopsy needle extends from the proximal end towards the distal end and from the distal end towards the proximal end.

12. An apparatus comprising:

a biopsy needle having a distal end and a proximal end, all or a portion of the biopsy needle being movable between a collapsed state and an expanded state;

a sheath having a distal end and a proximal end,

wherein the biopsy needle in the collapsed state is contained within the sheath, and in the expanded state at least the distal end of the biopsy needle extends from the distal end of the sheath;

wherein the biopsy needle is provided with two or more sleeves, which at least partially overlap in the collapsed state and which cylindrically expand to provide an increased radius, relative to a radius in the collapsed state, for sampling in the expanded state,

wherein a cross section of the distal end of the biopsy needle in the expanded state is a substantially circular cross section; and

wherein the two or more sleeves are connected to a shaft of the needle, and an entire length of the needle is the two or more sleeves.

13. The apparatus of claim 12 , wherein a distal most edge of the needle is a chamfered edge.

14. The apparatus of claim 13 , wherein the two or more sleeves are made of nitinol.

15. The apparatus of claim 12 , wherein the two or more sleeves are generally cone shaped when in the expanded state.

16. The apparatus of claim 12 , wherein a sample core which is collected becomes elongated when the biopsy needle is returned to a collapsed state within the sheath; an inside surface of the two or more sleeves are provided with retaining mechanisms which extend toward the center of the biopsy needle; and a rotating mechanism in communication with the biopsy needle and the sheath that rotates the biopsy needle about a rotational axis of the biopsy needle as the biopsy needle moves along a longitudinal axis of the sheath.

17. An apparatus comprising:

a biopsy needle having a distal end and a proximal end, all or a portion of the biopsy needle being movable between a collapsed state and an expanded state;

a sheath having a distal end and a proximal end,

wherein the biopsy needle in the collapsed state is contained within the sheath, and in the expanded state at least the distal end of the biopsy needle extends from the distal end of the sheath;

wherein the biopsy needle is provided with two or more sleeves, which at least partially overlap in the collapsed state and which cylindrically expand to provide an increased radius, relative to a radius in the collapsed state, for sampling in the expanded state,

wherein a cross section of the distal end of the biopsy needle in the expanded state is a substantially circular cross section; and

wherein the two or more sleeves are made of nitinol and an entire length of the needle is the two or more sleeves.

18. The apparatus of claim 17 , wherein a distal most edge of the needle is a chamfered edge.

19. The apparatus of claim 18 , wherein the two or more sleeves are generally cone shaped when in the expanded state.

20. The apparatus of claim 17 , wherein a sample core which is collected becomes elongated when the biopsy needle is returned to a collapsed state within the sheath; an inside surface of the two or more sleeves are provided with retaining mechanisms which extend toward the center of the biopsy needle; and a rotating mechanism in communication with the biopsy needle and the sheath that rotates the biopsy needle about a rotational axis of the biopsy needle as the biopsy needle moves along a longitudinal axis of the sheath.