Plasma Probe

Abstract

A concept for reliable and simple connection of a heat-resistant end piece (17) to a hose body (18) is described, and particularly a multiple lumen hose body (18). The connection technique is simple and reliable and leads to high quality probes having a long lifetime.

Claims

1. A plasma probe (12), comprising: a hose body (18) that comprises a jacket section (22) configured in a manner limiting at least one lumen (19, 20, 21) and a center section (26), which is connected with the jacket section (22) by at least one wall section (23); and an end piece (17) that is arranged at a distal end (15) of the hose body (18) and comprises a passage channel (29) as well as a tube shank (30) that extends into the hose body (18); wherein between the jacket section (22) and the at least one wall section (23, 24, 25) respectively one slit (34, 35, 36) is formed that extends in a proximal direction from the distal end (15) of the hose body (18); wherein the tube shank (30) extends into the slit (34, 35, 36).

2. The plasma probe according to claim 1, wherein the hose body (18) comprises a flexible plastic.

3. The plasma probe according to claim 1, wherein the jacket section (22), the at least one wall section (23) and the center section (26) are connected with one another in a seamless monolithic manner.

4. The plasma probe according to claim 1, wherein the hose body (18) has a constant cross-section along its entire length.

5. The plasma probe according to claim 1, wherein the end piece (17) is made of a heat-resistant plastic, a metal, or a ceramic.

6. The plasma probe according to claim 1, wherein the slit (34, 35, 36) comprises a length that is longer than the length of the tube shank (30).

7. The plasma probe according to claim 1, wherein the passage channel (29) of the tube shank (30) comprises a wall against which the at least one wall section (23) abuts with an end thereof facing the jacket section (22).

8. The plasma probe according to claim 7, cha wherein the jacket section (22) is cylindrically configured at least in an area of the tube shank (30).

9. The plasma probe according to claim 1, wherein the at least one wall section (23) is deformed inside of the tube shank (30).

10. The plasma probe according to claim 1, wherein the tube shank (30) is provided with an anchoring structure (31) on a radial outer surface of the tube shank (30).

11. The plasma probe according to claim 1, wherein an electrical conductor (27) is arranged in the center section (26).

12. The plasma probe according to claim 11, wherein an electrode body (38) is held in the center section (26).

13. The plasma probe according to claim 12, wherein the electrode body (38) is configured in a tube shape and extends between the electrical conductor (27) and the center section (26).

14. The plasma probe according to claim 12, wherein the electrode body (38) comprises a heat-resistant electrically conductive material and an electrically conductive coating (39) on a surface of the electrode body, wherein the electrically conductive coating (39) has a melting temperature which is lower than a melting temperature of the heat-resistant electrically conductive material of the electrode body (38).

15. A method for manufacturing a plasma probe, the plasma probe comprising a hose body (18) comprising a jacket section (22) having at least one lumen (19, 20, 21) and a center section (26) that is connected with the jacket section (22) by at least one wall section (23); and an end piece (17) configured to be arranged on a distal end (15) of the hose body (18) and that comprises a passage channel (29) as well as a tube shank (30); wherein the method comprises: creating a slit (34) between the jacket section (22) and the at least one wall section (23) originating from the distal end (15) of the hose body (18) in a proximal direction; and inserting the tube shank (30) in the slit (34) under displacement of the at least one wall section (23) out of the slit (34).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Further details of advantageous embodiments of the invention are derived from the dependent claims and/or the figures of the drawings along with the associated description. The drawings show:

[0028] FIG. 1 an apparatus with enclosed probe in a schematic basic illustration,

[0029] FIG. 2 the distal end of the probe according to FIG. 1 in a perspective enlarged illustration,

[0030] FIG. 3 the distal end of the probe according to FIG. 2 in an exploded illustration without electrode,

[0031] FIGS. 4-6 different conditions during the provision of the hose body of the probe prior to the assembly of the end piece,

[0032] FIG. 7 the hose body in deformed condition with inserted end piece in a perspective illustration,

[0033] FIG. 8 the hose body according to FIG. 7 with assembled electrode in a perspective illustration,

[0034] FIG. 9 the distal end of the probe in a longitudinally cut illustration,

[0035] FIG. 10 the probe according to FIG. 9 with wall sections obliquely orientated relative to a radial line with view on the distal end of the probe and

[0036] FIG. 11 the probe in an illustration according to FIG. 10, however, with radially arranged compressed wall sections.

DETAILED DESCRIPTION

[0037] In FIG. 1 a plasma probe 12 is illustrated, the proximal end 13 of which is connected to an apparatus 14 for supply of the probe 12. The probe can be configured as plasma probe, particularly argon plasma probe. The apparatus then comprises the required components for supply of the probe 12, e.g. with radio frequency voltage and current and with a gas, particularly inert gas, particularly argon. Instead of one single apparatus 14 also multiple apparatus can be provided, each of which takes over an individual task, e.g. the supply of the probe 12 with current or the supply of the probe 12 with a suitable gas.

[0038] The probe 12 comprises a distal end 15 that lets out a plasma jet for influencing biological tissue of an animal or human patient. The probe 12 can be positioned so that the distal end 15 of probe 12 is directly located at the tissue section to be treated, e.g. through the working channel of an endoscope or through a suitable body lumen. The plasma jet of probe 12 exits from a distal opening 16 that is apparent from FIG. 2. The opening 16 is formed on an end piece 17 consisting of a heat-resistant material that is held on the hose body 18 of probe 12. While the hose body 18 consists of a flexible plastic, such as PTFE, PA12, PEBAX, polyethylene or the like, the end piece 17 is made from a typically rigid, i.e. less flexible, but in turn heat-resistant material, such as ceramic, heat-resistant plastic or the like.

[0039] The hose body 18 encloses at least one and here three lumen 19, 20, 21, as apparent from FIG. 3, which are separated to the outward by a jacket section 22 and from one another by wall sections 23, 24, 25. The wall sections 23, 24, 25 extend from the jacket section 22 to a center section 26 with which they are connected in a seamless and monolithic manner. This configuration of the hose body 18 is particularly apparent from FIG. 4. The hose body 18 thus forms a monolithic seamless body consisting of uniform material. The center section 26 can have a substantially round or other (e.g. polygonal) cross-section and can be arranged centrally relative to the otherwise hollow cylindrical jacket section 22. Centrally in the center section 26 an electrical conductor 27 can be arranged that extends over the entire length of the hose body 18 through the center section 26. The conductor 27 can be a bare conductor or a conductor 27 insulated by means of a varnish or plastic coating. The wall sections 23, 24, 25 can be inclined relative to the radial direction, as is preferred. The wall sections 23, 24, 25 can be realized flat or curved. The radial direction extends radially away from conductor 27 that in turn extends axially. The axial direction A is indicated by an arrow in FIG. 4. The radial direction is any direction extending orthogonal thereto.

[0040] The end piece comprises a hollow body 28 on which opening 16 is configured as distal end opening, for example, as illustrated in FIGS. 2 and 3. The opening 16 of the otherwise central passage channel 29 can, however, also be arranged laterally on body 28. In addition, body 28 can comprise multiple of such openings 16 connected with the passage channel 29, e.g. distributed along its circumference. The distal end of body 28 can then be closed.

[0041] Preferably body 28 is rotationally symmetrically configured and encloses a passage channel 29 that ends at the opening 16. The passage channel 29 extends through body 28 and a tube shank 30, which adjoins body 28 and is preferably a monolithic part thereof. The tube shank 30 is preferably hollow cylindrically configured, whereby it can comprise anchoring means 31 on its outer circumference surface, such as ring beads 32, 33 having a saw-tooth-like profile, individual teeth or threads. The outer diameter of tube shank 30 is preferably at least slightly larger than the inner diameter of the cylindrical jacket section 22. On the distal end of tube shank 30 in the transition to body 28 a ring shoulder 40 is formed against which the face of jacket section 22 may abut.

[0042] For connection of end piece 17 with hose body 18 the following is carried out:

[0043] In a first step hose body 18 is provided, as illustrated in FIG. 4. The hose body 18 can be produced as continuous material by extrusion and first cut to the desired length by means of a suitable cutting tool, such as scissors or the like. At its proximal end then a supply line or a suitable connector can be connected, wherein the required space thereof plays a minor role. Special attention is paid however on the distal end and the connection of the end piece 17. For this, at least as an option, a portion is cut from the distal end of hose body 18 with a suitable cutting tool so that the conductor 27 is exposed. This simplifies the attachment of the electrode later, whereby this step can also be omitted.

[0044] The next indeed important step with relation to the attachment of the end piece 17 is the separation of the connection between the jacket section 22 and the wall sections 23, 24, 25. For this respective cuts are made along the inner circumferential surface of the jacket section 22, as indicated in FIG. 6, the cuts separating the wall sections 23, 24, 25 in the respective transition to the jacket section 22. The cuts 34-36 are indicated by dashed lines in FIG. 6. They extend over an axial distance in proximal direction into the hose body 18, whereby the distance is preferably longer than the axial length of the tube shank 30 (FIG. 3).

[0045] For mounting the end piece 17 on the hose body 18 the tube shank 30 is now inserted into the cuts 34-36 so that it moves between the wall sections 23, 24, 25 and the jacket section 22. Thereby the wall sections 23, 24, 25 are deformed radially inwardly, as shown in FIG. 7. The inner contour of tube shank 30 is marked by a dashed ellipse 37 in FIG. 7. The walls 23 to 25 orientated obliquely relative to the radial direction yield radially inwardly and are in so far slightly bent.

[0046] The exposed end of conductor 27 can serve itself as electrode. Additionally or alternatively, however, an electrode body 38 can be moved on the exposed end of conductor 27 and can be inserted into the center section 26 of hose body 18, as shown in FIG. 8 and particularly FIG. 9. FIG. 9 particularly illustrates the slits 34, 36 that are caused by tube shank 30 by means of deformation of the wall sections 23, 25 (as well as the cut away wall section 24 in FIG. 9). In FIG. 9 also electrode body 38 is apparent, which is configured as tube and takes the conductor 27 in the interior while it extends into the center section 26 under expansion thereof. This is independent from whether the conductor 27 has first been exposed according to FIG. 5 or whether the cuts 34, 35, 36 for mounting the end piece, i.e. for taking the tube shank 30, have been directly carried out on hose body 18 according to FIG. 4.

[0047] FIG. 10 illustrates the probe according to the invention again with a view into the passage channel 29. As apparent, the wall sections 23, 24, 25, which extend approximately tangentially from the center section 26 and which are cut free at the radial outer side, are displaced inwardly by the end piece 17 so that they abut against the wall of the passage channel 29. The lumen 19, 20, 21 are slightly narrowed by the tube shank and the wall sections 23, 24, 25, which slightly increases the flow velocity of the gas supplied by lumen 19, 20, 21 in the range of end piece 17.

[0048] The wall sections 23, 24, 25 do not have to be necessarily arranged obliquely relative to the radial direction and thus extend tangentially from the center section 26. They can also be arranged differently and can be orientated radially according to FIG. 11, for example. The insertion of the tube shank of end piece 17 into the slits between the wall sections 23, 24, 25 and the jacket section 22 can thereby result in a certain compression of wall sections 23 to 25, which is illustrated in FIG. 11 in a symbolic exaggerated manner. It has no influence on the details of the function of probe 12.

[0049] During operation apparatus 14 supplies lumen 19, 20, 21 of probe 12 with a suitable gas, e.g. an inert gas, such as argon. It then flows through the lumen 19, 20, 21 from the proximal end 13 of probe 12 to the distal end 15 and exits there from opening 16. By means of apparatus 14 conductor 27 and therewith electrode body 38 is applied with a high voltage relative to a neutral electrode attached to the patient. From the electrode body 38 a gas discharge originates therefore that ionizes the gas flow, so that a plasma jet exits the opening 16 via which the current supplied by generator 14 flows to the patient and via the not further illustrated neutral electrode back to generator 14. Particularly, if electrode body 38 is coated with a low-melting metal 39, particularly silver, the discharge footpoint of gas discharge concentrates on the distal end of electrode body 38. The heat introduction into the center section 26 of hose body 18 can be thereby kept low, particularly if electrode body 38 consists of a thermally low conductive material, e.g. stainless steel. The tube shank 30 narrows the open flow cross-section of lumen 19, 20, 21. The electrode body 38 widens center section 26, whereby lumen 19, 20, 21 are further narrowed. In doing so, a nozzle effect is created in the range of the tube section that contributes to a good cooling of the center section. In doing so, the plastic of center section 26 can directly contact and hold electrode body 38 without being damaged thereby.

[0050] The invention provides a concept for reliable and simple connection of a heat-resistant end piece 17 to a hose body 18, particularly a multiple lumen hose body 18. The connection technique according to the invention is simple and reliable and leads to high quality probes having a long lifetime.

REFERENCE SIGNS

[0051] 12 probe [0052] 13 proximal end of probe [0053] 14 apparatus [0054] 15 distal end [0055] 16 opening [0056] 17 end piece [0057] 18 hose body [0058] 19-21 lumen [0059] 22 jacket section [0060] 23-25 wall sections [0061] 26 center section [0062] 27 conductor [0063] A axial direction [0064] 28 body [0065] 29 passage channel [0066] 30 tube shank [0067] 31 anchoring means [0068] 32-33 ribs (ring beads) [0069] 34-36 cuts [0070] 37 ellipse [0071] 38 electrode body [0072] 39 coating [0073] 40 ring shoulder