Plasma-generating device, plasma surgical device and use of a plasma surgical device

1. A plasma-generating device, comprising:

a plasma chamber;

an anode;

a cathode having a tapering tip, the tapering tip having a first portion disposed proximal to the plasma chamber and a second portion extending into the plasma chamber and terminating proximal of the anode, the anode and the cathode configured to establish an electric arc with a current of about 4-10 A to generate plasma having a temperature of at least 10,000° C.;

a plasma outlet configured to discharge the plasma as a charged plasma jet out of the plasma-generating device at a temperature of at least 10,000° C.; and

a coolant channel configured to receive a coolant such that the coolant flowing through the coolant channel cools a portion of the plasma-generating device adjacent to the cooling channel.

2. The plasma-generating device of claim 1 , wherein the coolant channel includes a coolant outlet configured to discharge the coolant.

3. The plasma-generating device of claim 2 , wherein the coolant outlet is arranged around the plasma outlet such that the coolant discharged through the coolant outlet restricts a flow of the plasma discharged from the plasma outlet.

4. The plasma-generating device of claim 2 , wherein the coolant channel is configured to discharge the coolant through the coolant outlet at a rate of between 1 and 5 ml/s.

5. The plasma-generating device of claim 1 , further comprising:

a plasma channel extending longitudinally from the plasma chamber to the plasma outlet, the plasma channel and the plasma outlet defining a discharge path for the plasma.

6. The plasma-generating device of claim 5 , wherein the coolant channel is parallel to the plasma channel.

7. The plasma-generating device of claim 5 , wherein the tapering tip of the cathode is disposed a non-zero distance away from an inlet of the plasma channel.

8. The plasma-generating device of claim 5 , wherein the plasma channel is configured to discharge a plasma jet through the plasma outlet, and the coolant channel includes a coolant outlet configured to discharge the coolant to restrict the plasma jet.

9. A plasma-generating device, comprising:

an anode;

a cathode having a tapering tip, the tapering tip narrowing toward the anode and terminating proximal of the anode, the anode and the cathode configured to establish an electric arc with a current of about 4-10 A to generate charged plasma having a temperature of at least 10,000° C.;

a sleeve having a portion that surrounds a portion of the tapering tip, the portion of the sleeve having a constant inner diameter such that a space between an inner surface of the sleeve and the cathode increases along a length of the tapering tip in a distal direction;

an outlet disposed at an end of the sleeve and being configured to discharge the charged plasma as a charged plasma jet out of the plasma-generating device at a temperature of at least 10,000° C., the charged plasma jet configured to treat biological tissue; and

a coolant channel configured to receive a coolant such that the coolant flowing through the coolant channel cools a portion of the plasma-generating device adjacent to the cooling channel.

10. The plasma-generating device of claim 9 , wherein the coolant channel includes a coolant outlet that is disposed in the anode.

11. The plasma-generating device of claim 10 , wherein the coolant outlet is arranged around a plasma outlet such that the coolant discharged through the coolant outlet restricts a flow of the plasma discharged from the plasma outlet.

12. The plasma-generating device of claim 10 , wherein the coolant channel is configured to discharge the coolant through the coolant outlet at a rate of between 1 and 5 ml/s.

13. A plasma-generating device, comprising:

an insulator sleeve having a distal end;

an anode;

a cathode having a tapered portion, the tapered portion having a first portion disposed within the insulator sleeve and a second portion projecting beyond the insulator sleeve and terminating proximal of the anode, the anode and the cathode configured to establish an electric arc with a current of about 4-10 A to generate plasma having a temperature of at least 10,000° C.;

a plasma channel extending longitudinally from the cathode and having an outlet at an end of the plasma channel, the outlet configured to discharge the plasma as a charged plasma jet out of the plasma-generating device at a temperature of at least 10,000° C. to treat biological tissue; and

a coolant channel configured to receive a coolant such that the coolant flowing through the coolant channel cools a portion of the plasma-generating device adjacent to the cooling channel.

14. The plasma-generating device of claim 13 , wherein at least a portion of the coolant channel is parallel to the plasma channel.

15. The plasma-generating device of claim 13 , wherein the coolant channel includes a coolant outlet configured to discharge the coolant.

16. The plasma-generating device of claim 15 , wherein an angle between a direction of the coolant channel at the outlet and a direction of the plasma channel is between +30 and −30 degrees.

17. The plasma-generating device of claim 16 , wherein the angle is zero.

18. The plasma-generating device of claim 15 , wherein the outlet of the coolant channel angles toward the outlet of the plasma channel.

19. The plasma-generating device of claim 13 , wherein the tapered portion of the cathode is disposed a non-zero distance away from an inlet of the plasma channel.

20. The plasma-generating device of claim 1 , wherein a distal end of the plasma-generating device has an outer dimension that is equal to or less than 5 mm.

21. The plasma-generating device of claim 1 , wherein the outlet of the coolant channel angles away from the outlet of the plasma channel.

22. The plasma-generating device of claim 1 , further comprising:

at least one intermediate electrode arranged at least partly between the anode and the cathode.

23. The plasma-generating device of claim 5 , wherein the plasma channel is configured to discharge a plasma jet through the plasma outlet to treat biological tissue, and the coolant channel is configured to discharge the coolant through a coolant outlet to cool the biological tissue.

24. The plasma-generating device of claim 5 , wherein the plasma channel has a diameter of between 0.2 mm and 0.5 mm.

25. The plasma-generating device of claim 1 , wherein the electric arc has a cross-section of between 0.2 mm and 0.5 mm.