Plasma probe

Abstract

The present invention provides a solution for reliably and simply connecting a heat-resistant end piece (17) to a hose body (18), in particular to a plurality of lumen hose bodies (18). The connection technique according to the invention is simple and reliable and leads to a high-quality probe with a long service life.

Description

Technical Field

[0001] The present invention relates to a plasma probe, particularly for endoscopic treatment of human or animal patients, and a method for manufacturing such a plasma probe. Background Technology

[0002] A general-purpose plasma probe is known from DE 100 30 111B4, comprising a flexible tube surrounding a single inner cavity, the tube having a ceramic interface at its distal end. An electrical conductor is arranged inside the tube, forming an electrode centrally located within the interface at its distal end. During operation, a suitable gas flows distally through the inner cavity and ionizes at the electrode, causing a plasma jet to exit the interface.

[0003] To attach the interface to the hose, it includes a handle that extends into the hose.

[0004] DE 696 32 080T2 also discloses a plasma probe having a flexible tube body with an end member made of ceramic or PTFE at its distal end. Similarly, the end member includes a handle extending into the flexible tube to establish a connection between the end member and the flexible tube.

[0005] To center the electrode, different measures are provided in the prior art. According to DE 69632 080T2, the electrode may include a helical winding section, the coil of which abuts against the hose or end member from the inside, and the last coil of which centers and holds the needle electrode in the end member.

[0006] According to DE 100 30 111B4, as an alternative, a sheet-shaped element can be provided for centering the electrode, wherein the lateral edge of the sheet abuts against the hose from the inside, and its distal tip itself serves as the electrode.

[0007] Both schemes have reached their limits as they become increasingly miniaturized. Summary of the Invention

[0008] Therefore, the object of the present invention is to provide an improved scheme for constructing the distal end of a probe.

[0009] This objective is achieved by a probe having the features of claim 1. Claim 15 relates to a method particularly suitable for manufacturing the probe according to claim 1.

[0010] The plasma probe according to the invention comprises a flexible tube body surrounding at least one inner cavity. This inner cavity is radially confined to the environment by means of a sheath section of the flexible tube body. The term "radial" thus refers to the radial direction if the longitudinal extension of the plasma probe is considered the axial direction. The sheath section is connected to a central section by means of at least one wall section, wherein the central section may be centrally located at or slightly offset from the center of the flexible tube body. Preferably, instead of providing only one wall section, multiple wall sections, such as three, are provided, which divide the interior of the flexible tube body into multiple cavities and simultaneously hold the central section of the flexible tube body in a desired position, such as a central position. The central section, wall sections, and sheath section are preferably part of an integral flexible tube body, i.e., they are made of the same material and are adjacent to each other without seams or joints.

[0011] An end member, typically made of a heat-resistant material such as heat-resistant plastic or ceramic, is disposed at the distal end of the hose body. The end member includes a central passage opening with a nozzle that allows gas or plasma to exit. The nozzle may be located on the distal end surface of the end member or in its lateral region. Multiple nozzles may also be provided.

[0012] The end member includes a handle extending into the hose body. For this purpose, a slit is formed between a sheath section and one or more wall sections of the hose body, wherein the slit extends proximally into the hose body from the distal end of the hose body for a length preferably at least as long as the handle of the end member, measured axially. The handle is inserted into the slit, thereby displacing the wall sections radially inward such that they abut against the inner wall of the passage opening of the handle.

[0013] The wall sections of the hose body can be arranged radially or obliquely relative to the radial direction. If they are obliquely arranged, they can easily open a slot for the handle when they are slightly bent. If they are radially arranged, they open a slot for the handle when they are bent and / or compressed.

[0014] Because the handle is positioned in the gap between the wall section and the sheath section, assembly of the end member at the hose with the wall section between the sheath section and the center section is particularly simple. No material needs to be removed from the inside of the hose body. It is sufficient to provide a cut in the wall section along the inner surface of the sheath section, i.e., to separate the wall section from the sheath section, for example, by means of the cut. Because the open lumen of the hose body is narrowed by the handle of the end member on the one hand, and the wall section is compressed or bent inward on the other hand, a nozzle effect is generated inside the handle of the end member, which is advantageous for operation as a plasma probe. In particular, it effectively reduces excessive heat introduction into the plasma probe.

[0015] The hose body can be formed from flexible, particularly bending, elastic plastics (such as PTFE, PE, etc.). Preferably, the sheath section, wall sections (or multiple wall sections), and central section are thus primarily formed together. For example, the hose body can be manufactured as a single unit by extrusion.

[0016] By dividing the interior into two, three, or more cavities using wall sections, high flexibility is achieved, and the gas passage through the hose body remains unobstructed when the hose body bends, even with small bending radii. This is particularly advantageous if the wall sections are arranged at an angle relative to the corresponding radial direction.

[0017] Preferably, the hose body may have a constant cross-section along its entire length, extending from the proximal end to the distal end. The distal end is the end facing the patient for treatment. The proximal end is the end to be connected to the supply device. The cross-section of the hose body thus refers to the surface whose surface normal is oriented parallel to the longitudinal direction of the hose body, extending from the proximal side to the distal side.

[0018] As previously mentioned, the end component can be made of heat-resistant plastic or ceramic. This is particularly suitable for the construction of probes used as monopolar plasma probes, where a single electrode is held in or on the central section of the tube body and used for plasma generation. However, the end component may also be made of metal and connected, for example, to a neutral conductor. The probe can then be implemented as a bipolar probe, in which a discharge occurs between the central electrode and the end component. Gas flowing through the discharge section can thus be ionized, thereby generating a plasma jet that exits the probe at the distal end.

[0019] The end member's handle is used to attach the end member to the hose body. For this purpose, a sheath section is placed on the outer surface of the handle, while a wall section abuts against the wall of the passage opening on its inner side. If the outer diameter of the handle is slightly larger than the inner diameter of the sheath section, the sheath section can thus abut against the handle under preload. Additionally, anchoring structures can be provided on the outer side of the handle, for example, in the form of ribs, teeth, or threads.

[0020] The central section of the hose body may include an electrical conductor, preferably extending along the entire length of the hose body. The central section may be configured to surround the conductor. At the proximal end of the hose body, the conductor may be connected to a generator by means of a suitable connecting device (e.g., a connector). At the distal end, the electrical conductor may form an electrode or be connected to an electrode. For example, the electrode may be configured as a small tubular electrode and may be supported and contacted by the conductor. The tubular electrode may be inserted in the central section of the hose body between the conductor and the plastic material of the hose body, which expands outward therefrom. In the event of deformation of the hose, particularly its central section, the electrode is thus held therein by means of a clamping effect. This may slightly expand the central section, thereby narrowing the flow cross-section in the hose handle and thereby increasing the gas flow rate.

[0021] Although not strictly necessary, it is advisable to expose the conductor before attaching the electrode, such that the conductor initially protrudes from the tubular body in the distal direction. The tubular electrode can be moved first onto this conductor and then into the central section. This can be omitted if a needle electrode is used. The needle electrode is then simply inserted into the central section near the conductor.

[0022] It has been proven advantageous to make electrodes from heat-resistant and conductive materials such as stainless steel, hard metals, imaginable steel, tungsten, cermet, or conductive ceramics. The electrodes may also be coated with a metallic coating, particularly of metals such as silver, whose melting temperature is lower than that of the electrode material. This has been proven to stabilize the discharge originating from the electrode and to concentrate its discharge footpoint, particularly at the distal end of the electrode.

[0023] Claim 15 relates to a particularly simple and reliable method for manufacturing the plasma probe. For this purpose, a flexible tube body having one or more cavities is first provided. Adjacent to the inner side of the sheath section, the connection between the wall section and the sheath section is separated by a slit. The corresponding slit comprises a length of several millimeters in the axial direction and is preferably longer than the shank of the end member measured in the axial direction. Preferably, the slit is made by means of a cutter moving in the axial and / or circumferential directions without removing material, thereby preventing the generation of debris or other particles (plastic particles) that could potentially enter the cavity or adhere to the probe portion and subsequently cause malfunction.

[0024] After the slits are made, the end member's handle is moved into the slots (multiple slots), where wall sections (or multiple wall sections) are displaced out of the slots. This helps to narrow the flow cross-section within the end member's tube section and thus increases the flow velocity at that location. This supports cooling of the central section that can be used to fix the electrode. Attached Figure Description

[0025] Further details of advantageous embodiments of the invention are derived from the dependent claims and / or the accompanying drawings, together with the description. Wherein:

[0026] Figure 1 A schematic basic diagram illustrates a device with an enclosed probe.

[0027] Figure 2 The diagram is shown with a perspective magnification based on Figure 1 The distal end of the probe,

[0028] Figure 3 An exploded view is shown without electrodes according to Figure 2 The distal end of the probe,

[0029] Figure 4-6 The different states of the probe tube body are shown before the end components are assembled.

[0030] Figure 7 The perspective view shows the hose body in its deformed state with the end component inserted.

[0031] Figure 8 The perspective view shows the situation with the electrodes assembled. Figure 7 The main body of the hose,

[0032] Figure 9 The distal end of the probe is shown in a longitudinal cross-section.

[0033] Figure 10 A view of the distal end of the probe shows the results according to Figure 9 The probe, wherein the wall section is tilted relative to the radial line, and

[0034] Figure 11 According to Figure 10 The illustration shows the probe, but the wall sections are arranged radially in compression. Detailed Implementation

[0035] exist Figure 1 The diagram illustrates a plasma probe 12, with its proximal end 13 connected to a device 14 for supplying the probe 12. The probe may be constructed as a plasma probe, particularly an argon plasma probe. The device then includes the necessary components for supplying the probe 12 with, for example, radio frequency voltage and current, and with a gas (particularly an inert gas, particularly argon). Instead of a single device 14, multiple devices may be provided, each responsible for a separate task, such as supplying the probe 12 with current or with a suitable gas.

[0036] The probe 12 includes a distal end 15 that emits a plasma jet to affect biological tissue in an animal or human patient. The probe 12 can be positioned such that the distal end 15 is directly located at the tissue segment to be treated, for example, through the working channel of an endoscope or through a suitable body cavity. The plasma jet of the probe 12 originates from... Figure 2 The distal opening 16 is visible in the middle. The opening 16 is formed on the end member 17, which is made of heat-resistant material and is held on the hose body 18 of the probe 12. The hose body 18 is made of a flexible plastic such as PTFE, PA12, PEBAX, polyethylene, etc., while the end member 17 is made of a generally rigid (i.e., less flexible) but heat-resistant material, such as ceramic, heat-resistant plastic, etc.

[0037] As from Figure 3 As can be seen, the hose body 18 surrounds at least one, and here three, inner cavities 19, 20, 21, which are separated from the outside by a sheath section 22 and separated from each other by wall sections 23, 24, 25. The wall sections 23, 24, 25 extend from the sheath section 22 to the central section 26, and they are connected to the central section in a seamless and integral manner. This construction of the hose body 18... Figure 4 This is particularly evident in the hose body 18. Therefore, the hose body 18 forms a single, seamless unit made of a uniform material. The central section 26 may have a substantially circular or other (e.g., polygonal) cross-section and may be centrally located relative to the originally hollow cylindrical sheath section 22. At the center of the central section 26, an electrical conductor 27 may be arranged, extending through the central section 26 along the entire length of the hose body 18. The conductor 27 may be a bare conductor or a conductor insulated by means of a varnish or plastic coating. Preferably, the wall sections 23, 24, 25 may be inclined relative to the radial direction. The wall sections 23, 24, 25 may be implemented as flat or curved. The radial direction extends radially away from the conductor 27, which in turn extends axially. The axial direction A is... Figure 4 The arrow indicates the direction. The radial direction is any direction that extends orthogonally to it.

[0038] The end component includes a hollow body 28, on which an opening 16 is configured as a distal opening, for example, as... Figure 2 and Figure 3 As shown in the diagram. However, the opening 16 of the original central passageway 29 can also be arranged laterally on the body 28. Additionally, the body 28 may include a plurality of such openings 16 connected to the passageway 29, for example, distributed along its circumference. Then the distal end of the body 28 can be closed.

[0039] Preferably, the body 28 is constructed rotationally symmetrically and surrounds a passageway 29 terminating at the opening 16. The passageway 29 extends through the body 28 and a handle 30, which is adjacent to and preferably integral with the body 28. The handle 30 is preferably constructed as a hollow cylinder, thereby allowing it to include anchoring devices 31, such as annular protrusions 32, 33 with a serrated shape, individual teeth, or threads, on its outer circumferential surface. The outer diameter of the handle 30 is preferably at least slightly larger than the inner diameter of the cylindrical sheath section 22. An annular shoulder 34 is formed at the distal end of the handle 30 transitioning into the body 28, and the face of the sheath section 22 may abut against this annular shoulder.

[0040] To connect end component 17 to hose body 18, the following steps are performed:

[0041] In the first step, such as Figure 4 As shown, a hose body 18 is provided. The hose body 18 can be manufactured as a continuous material by extrusion and is first cut to the desired length using a suitable cutting tool such as scissors. A supply line or suitable connector can then be connected to its proximal end, where the required space is secondary. However, particular attention is paid to the connection at the distal end and the end member 17. For this purpose, at least as an alternative, a portion is cut from the distal end of the hose body 18 using a suitable cutting tool, thereby exposing the conductor 27. This simplifies the subsequent attachment of the electrodes, thus eliminating this step.

[0042] The next truly important step related to the attachment of end member 17 is to separate the connection between sheath section 22 and wall sections 23, 24, 25. For this purpose, as follows... Figure 6 As shown, corresponding cuts are made along the inner circumferential surface of the sheath section 22, and these cuts separate the wall sections 23, 24, and 25 in their respective transitions to the sheath section 22. Cuts 34-36 are... Figure 6 The dotted lines indicate this. They extend into the hose body 18 at a certain axial distance in the proximal direction, whereby this distance is preferably longer than the axial length of the handle 30. Figure 3 ).

[0043] To mount the end component 17 onto the hose body 18, the handle 30 is now inserted into the cuts 34-36, allowing it to move between the wall sections 23, 24, 25 and the sheath section 22. Figure 7 As shown, wall sections 23, 24, and 25 deform radially inward. The internal profile of the handle 30 is... Figure 7 Marked by the dashed ellipse 37. The walls 23 to 25, which are inclined relative to the radial direction, buckle radially inward and are slightly curved up to this point.

[0044] The exposed end of conductor 27 can itself be used as an electrode. However, additionally or alternatively, such as Figure 8And especially Figure 9 As shown, the electrode body 38 is movable over the exposed end of the conductor 27 and can be inserted into the central section 26 of the hose body 18. Figure 9 The illustration specifically shows the handle 30 using wall sections 23, 25 (and) Figure 9 The gaps 34 and 36 are created by the deformation of the wall section 24 that was cut off in the middle. Figure 9 In the image, electrode body 38 is also visible. This electrode body is constructed as a tube and internally houses conductor 27. Furthermore, the electrode body extends into central section 26 as the central section expands. This relates to whether conductor 27 has been... Figure 5 Firstly, whether the cutouts 34, 35, 36 that are first exposed or used for mounting end components (i.e., for receiving the handle 30) have been... Figure 4 It is irrelevant to direct application on the hose body 18.

[0045] Figure 10 The probe according to the invention is again illustrated from a view into the passageway 29. Clearly, the wall sections 23, 24, 25, extending generally tangentially from the central section 26 and cut radially outward, are displaced inward by the end member 17 such that they abut against the wall of the passageway 29. The cavities 19, 20, 21 are slightly narrowed by the handle and wall sections 23, 24, 25, which slightly increases the flow rate of gas supplied from the cavities 19, 20, 21 within the end member 17.

[0046] Wall sections 23, 24, and 25 need not be arranged at an angle relative to the radial direction and therefore extend tangentially from the central section 26. They may also be arranged differently and, for example, according to Figure 11 Radial orientation. Inserting the handle of end member 17 into the gap between wall sections 23, 24, 25 and sheath section 22 can cause a certain degree of compression in wall sections 23 to 25, which... Figure 11 The illustration is presented in a symbolically exaggerated manner. It does not affect the details of the function of probe 12.

[0047] During operation, device 14 supplies a suitable gas, such as an inert gas like argon, to the cavities 19, 20, 21 of probe 12. This gas then flows from the proximal end 13 of probe 12 through the cavities 19, 20, 21 to the distal end 15, and exits from there through opening 16. By means of device 14, conductor 27 and its electrode body 38 are subjected to a high voltage relative to the neutral electrode attached to the patient. Thus, a gas discharge originates from electrode body 38, ionizing the gas flow, causing a plasma jet to exit through opening 16, through which current supplied by generator 14 flows to the patient, and returns to generator 14 via a neutral electrode (not further illustrated). In particular, if electrode body 38 is coated with a low-melting-point metal 39, especially silver, the discharge point of the gas discharge is concentrated at the distal end of electrode body 38. In particular, if electrode body 38 is constructed of a material with low thermal conductivity (e.g., stainless steel), heat introduction into the central section 26 of the tubing body 18 can thus be kept low. The handle 30 narrows the open flow cross-section of the inner cavities 19, 20, 21. The electrode body 38 widens the central section 26, thereby further narrowing the inner cavities 19, 20, 21. This creates a nozzle effect within the tube section, which contributes to good cooling of the central section. This also allows the plastic of the central section 26 to directly contact and hold the electrode body 38 without damage.

[0048] This invention provides a method for reliably and easily connecting a heat-resistant end component 17 to a hose body 18, particularly a plurality of inner-lumen hose bodies 18. The connection technique according to the invention is simple and reliable, and results in a high-quality probe with a long lifespan.

[0049] Figure Labels

[0050] 12 probes

[0051] 13. Proximal end of the probe

[0052] 14 Equipment

[0053] 15. Remote

[0054] 16 Openings

[0055] 17-end components

[0056] 18. Hose body

[0057] 19-21 Inner cavity

[0058] 22 Sheath Section

[0059] Sections 23-25

[0060] 26 Central Section

[0061] 27 Conductors

[0062] Axial direction

[0063] 28 main body

[0064] 29. Pathways and Channels

[0065] 30 pipe handle

[0066] 31 Anchoring device

[0067] 32-33 ribs (annular raised edge)

[0068] 34-36 incisions

[0069] 37 Ellipse

[0070] 38 Electrode Body

[0071] 39 Coating

Claims

1. A plasma probe (12) specifically for endoscopic treatment of human or animal patients, comprising: The hose body (18) includes a sheath section (22) constructed to restrict at least one inner cavity (19, 20, 21) and a central section (26) connected to the sheath section (22) by means of at least one wall section (23). An end component (17) is disposed at the distal end (15) of the hose body (18) and includes a passageway (29) and a handle (30) arranged to extend into the hose body (18). An electrical conductor (27) is provided, which can be connected to a generator via a connecting device at its proximal end of the hose body (18), and forms or is connected to an electrode at its distal end. in, A gap (34, 35, 36) is formed between the sheath section (22) and the wall section (23, 24, 25), respectively, and the gap extends proximally from the distal end (15) of the hose body (18). The handle (30) is arranged to extend into the slit (34, 35, 36), wherein the passageway (29) of the handle (30) includes a wall, the wall section (23) abutting against the wall at its end facing the sheath section (22) and deforming inside the handle (30).

2. The plasma probe according to claim 1, characterized in that, The hose body (18) is made of flexible plastic.

3. The plasma probe according to claim 1 or 2, characterized in that, The sheath section (22), the wall section (23), and the center section (26) are interconnected in a seamless, integral manner.

4. The plasma probe according to claim 1 or 2, characterized in that, The hose body (18) is constructed in such a way that it has a constant cross-section along its entire length.

5. The plasma probe according to claim 1 or 2, characterized in that, The end component (17) is made of heat-resistant plastic, metal or ceramic.

6. The plasma probe according to claim 1 or 2, characterized in that, The slits (34, 35, 36) include lengths longer than the length of the handle (30).

7. The plasma probe according to claim 1, characterized in that, The sheath section (22) is constructed in a cylindrical shape at least in the region of the handle (30).

8. The plasma probe according to claim 1 or 2, characterized in that, The handle (30) has an anchoring structure (31) on its radial outer surface.

9. The plasma probe according to claim 1 or 2, characterized in that, The electrical conductor (27) is arranged in the central section (26).

10. The plasma probe according to claim 1 or 2, characterized in that, The electrode body (38) is held in the central section (26).

11. The plasma probe according to claim 10, characterized in that, The electrode body (38) is configured in a tubular shape and extends between the electrical conductor (27) and the central section (26).

12. The plasma probe according to claim 10, characterized in that, The electrode body (38) is made of heat-resistant and conductive material, and at least one conductive coating (39) is provided on its surface, the melting temperature of which is lower than the melting temperature of the other electrode body (38) materials.

13. A method for manufacturing a plasma probe, particularly for endoscopic treatment of human or animal patients, comprising the following steps: A hose body (18) is provided, comprising a sheath section (22) configured to restrict at least one inner cavity (19, 20, 21) and a central section (26) connected to the sheath section (22) by means of at least one wall section (23). An end component (17) is provided, which is disposed on the distal end (15) of the hose body (18) and includes a passageway (29) and a handle (30). An electrical conductor (27) is provided, which can be connected to a generator via a connecting device at its proximal end of the hose body (18), and forms or is connected to an electrode at its distal end. A gap (34) is created between the sheath section (22) and the wall section (23), originating proximally from the distal end (15) of the hose body (18). With the wall section (23) displaced out of the gap (34), the tube handle (30) is inserted into the gap (34) and the wall section (23) is deformed inside the tube handle (30).

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