Biopsy needle for biopsy sampling, biopsy device, and methods of manufacturing a biopsy needle or a biopsy device
A biopsy needle ( 100 ) comprises a cannula ( 5 ) with a distal end ( 15 ), an inner needle ( 1 ) that has a sharpened distal end ( 16 ) and at least one biopsy cavity ( 7 ) that is located at a distance (L 3 ) from the sharpened distal end ( 16 ). The cannula ( 5 ) and the inner needle ( 1 ) are configured so that the inner needle ( 1 ) is accommodated inside the cannula ( 5 ) and the inner needle ( 1 ) and the cannula ( 5 ) are movable with regard to each other. The inner needle ( 1 ) further comprises at least two measuring electrodes ( 1, 4; 3, 4 ) for measuring a bioimpedance spectrum, the measuring electrodes ( 1, 4; 3, 4 ) defining a measuring volume that is localized to the distal end ( 16 ) of the inner needle ( 1 ).
1. A biopsy needle ( 100 ) for biopsy sampling, comprising:
a cannula ( 5 ) with a distal end ( 15 );
an inner needle ( 1 ) that has a sharpened distal end ( 16 ); and
at least one biopsy cavity ( 7 ) disposed in said inner needle ( 1 ) and that is located at a distance (L 3 ) from the sharpened distal end ( 16 ) of said inner needle ( 1 ); and wherein: the cannula ( 5 ) and the inner needle ( 1 ) are configured so that the inner needle ( 1 ) is accommodated inside the cannula ( 5 ) and the inner needle ( 1 ) and the cannula ( 5 ) are movable with regard to each other;
the inner needle ( 1 ) further comprising:
at least two measuring electrode pairs ( 1 , 4 ; and 3 , 4 ) for measuring a bioimpedance spectrum of tissue into which at least one pair of said at least two measuring electrode pairs ( 1 , 4 , and 3 , 4 ) are disposed, said at least pair one of the at least two measuring electrode pairs defining a measuring volume that is localized around a distal end ( 16 ) of the inner needle ( 1 ) , and wherein at least one of each of the at least two measuring electrode pairs ( 1 , 4 , and 3 , 4 ) is a wire electrode ( 4 ); and
a shell ( 3 ) that is a measuring electrode for one pair ( 3 , 4 ) of the at least two measuring electrode pairs includes a polymer filled core ( 2 ) that functions as an electrical insulation between the shell ( 3 ) and the wire electrode ( 4 ).
2. The biopsy needle ( 100 ) according to claim 1 , wherein: each measuring electrode of the at least two measuring electrode pairs ( 1 , 4 ; and 3 , 4 ) reach the sharpened distal end ( 16 ) of the inner needle ( 1 ) by extending to a surface of the sharpened distal end ( 16 ).
3. The biopsy needle ( 100 ) according to claim 1 , wherein: the inner needle ( 1 ) has a beveled needle facet ( 19 ) and wherein the measuring volume is focused on the beveled needle facet ( 19 ).
4. The biopsy needle ( 100 ) according to claim 3 , wherein: the biopsy needle ( 100 ) has a measurement sensitivity that is defined as a ratio between a volume in front of the sharpened distal end ( 16 ) of the inner needle ( 1 ) to the measuring volume, or alternatively, as the measurement sensitivity arising from a biopsy sampling volume ( 22 ) in front of the sharpened distal end ( 16 ) to the measuring volume.
5. The biopsy needle ( 100 ) according to claim 4 , wherein: the measurement sensitivity is greater than 50%.
6. The biopsy needle ( 100 ) according to claim 1 , wherein: the volume of the biopsy cavity ( 7 ) and the measuring volume are selected that at least 50% of the measuring volume is fitted into the biopsy cavity ( 7 ).
7. The biopsy needle ( 100 ) according to claim 1 , wherein: a position of at least one pair of measuring electrodes of the at least two measuring electrode pairs ( 1 , 4 ; and 3 , 4 )and a length (L 2 ) and location of the biopsy cavity ( 7 ) along the inner needle ( 1 ) have been selected in such a manner that a firing by a firing part ( 11 ) of a biopsy device ( 110 ) moves the biopsy cavity ( 7 ) in such a manner that a tissue sample whose bioimpedance spectrum has been measured at the time of firing is catched into the biopsy cavity ( 7 ).
8. The biopsy needle ( 100 ) according to claim 1 , wherein: a length (L 2 ) and location of the biopsy cavity ( 7 ) along the inner needle ( 1 ) have been selected in such a manner that a firing by a firing part ( 11 ) of a biopsy device ( 110 ) moves the biopsy cavity ( 7 ) into a measuring volume so that the measuring volume will be essentially covered by the biopsy cavity ( 7 ), most preferably so that a distance (L 4 ) between the biopsy cavity ( 7 ) and the measuring volume covers a range of 2 cm, 10.5-11.5 mm, 16.5-17.5 mm, or 21.5-22.5 mm.
9. The biopsy needle ( 100 ) according to claim 1 , wherein: the inner needle ( 1 ) further comprises a conduit ( 12 ) leading to the biopsy cavity ( 7 ) enabling vacuuming of the biopsy cavity ( 7 ).
10. The biopsy needle ( 100 ) according to claim 1 , wherein: the wire electrode ( 4 ) is placed eccentrically within the inner needle ( 1 ) in such way that the wire electrode ( 4 ) runs straight from a proximal end ( 17 ) of the inner needle ( 1 ) to the distal end ( 16 ) while passing the biopsy cavity ( 7 ) under a bottom of the biopsy cavity ( 7 ).
11. The biopsy needle ( 100 ) according to claim 10 , wherein: the wire electrode ( 4 ) is located at an edge of the inner needle ( 1 ).
12. The biopsy needle ( 100 ) according to claim 10 , wherein: the wire electrode ( 4 ) is curved within the inner needle ( 1 ) at the distal end ( 16 ) of the biopsy needle ( 100 ).
13. The biopsy needle ( 100 ) according to claim 10 , wherein: the biopsy needle ( 100 ) comprises two halves that have been placed against each other, comprising recesses ( 14 ) that form at least one passage ( 18 ) for the wire electrode ( 4 ).
14. The biopsy needle ( 100 ) in accordance with claim 1 , wherein: the inner needle ( 1 ) has a solid volume that is a measuring electrode.
15. The biopsy needle ( 100 ) according to claim 14 , wherein: the wire electrode ( 4 ) is located in a longitudinal recess ( 14 ) that is located in a solid volume on the opposite side of the biopsy cavity ( 7 ).
16. The biopsy needle ( 100 ) in accordance with claim 15 , wherein: the wire electrode ( 4 ) is insulated from the solid volume by a dielectric ( 13 ).
17. The biopsy needle ( 100 ) in accordance with claim 1 , wherein: said biopsy needle ( 100 ) is configured for use in a biopsy device ( 110 ) for biopsy sampling, said biopsy device further including:
i) a biopsy tool handle ( 6 ), to which the biopsy needle ( 100 ) has been attached or is attachable; and
ii) a firing part ( 11 ), which is configured to fire the inner needle ( 1 ) outwards from the cannula ( 5 ) and to make the cannula ( 5 ) to follow the inner needle ( 1 ) in such a way that at least the inner needle ( 1 ) moves a punch length (L) forward and the cannula ( 5 ) follows the inner needle ( 1 ) by moving from behind of the biopsy cavity ( 7 ) past the biopsy cavity ( 7 ) in order to capture a tissue sample.
18. The biopsy device ( 110 ) according to claim 17 , wherein: the biopsy needle ( 100 ) is configured to pick a tissue sample from a volume of tissue which spatially covers the measuring volume.
19. A method of manufacturing the biopsy needle ( 100 ) according to claim 1 , wherein: the biopsy needle ( 100 ) is constructed of two halves that are joined.
20. The method according to claim 19 , wherein: each of the halves comprises a recess ( 14 ), in such a manner that the joined biopsy needle ( 100 ) comprises a passage ( 12 ) for a wire electrode ( 4 ).
21. The method according to claim 20 , wherein: the passage ( 18 ) is curved at the distal end so that the wire electrode ( 4 ) will become curved when installed.
22. The method according to claim 21 , wherein: the radius of the curving of the passage ( 12 ) is selected by the intended use of the biopsy needle ( 100 ).
23. A method of manufacturing a biopsy needle ( 100 ) according to claim 1 , wherein: the wire electrode ( 4 ) is installed inside the biopsy needle ( 100 ) before or during the filling of the shell ( 3 ).
24. A method of manufacturing a biopsy needle ( 100 ) according to claim 1 , wherein: the core ( 2 ) and shell ( 3 ) are glued to each other.
25. A method of manufacturing a biopsy needle ( 100 ) according to claim 1 , wherein: the core ( 2 ) and shell ( 3 ) are joined together by using thermal expansion of the materials.