Ablation instrument

Abstract

To provide a plug for an ablation instrument entirely fabricated from plastic other than potentially provided electrical lines and capable of being rationally fabricated by an economical fabrication method by using, for example, an injection molding technique.SOLUTION: A plug 12 for an ablation instrument 11 is entirely fabricated from plastic other than potentially present electrical lines 25, 26, and can be rationally fabricated by an economical fabrication method by using, for example, an injection molding technique. Particularly, a pin unit 30 contributes thereto, and on the pin unit, pins 31, 32, 33, a sheet 43 for a fluid line 20, and a connection surface for a gas joint 45 made of plastic in the same manner are formed. In this configuration, the ablation instrument is particularly appropriate as single-use equipment, does not require valuable materials to be discarded or recycled about its disposal, and requires only plastic components which can be rationally fabricated.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an ablation instrument and a treatment device comprising such an ablation instrument, whereby the invention relates in particular to a CO ablation instrument that devitalizes living tissue by heat or cold. 2 This invention relates to a cooled thermal ablation instrument. The instrument may be provided with electrodes that introduce electrical current into the tissue to generate heat therein, whereby the electrodes are cooled internally to keep the electrode-tissue contact moist and conductive. However, the invention may also be used with instruments that do not have electrodes, which affect the tissue by cold. [Background technology]

[0002] A cryoprobe is known from CN 1480103, which is equipped at its distal end with an instrument tip that is cooled by the Joule-Thomson effect. The instrument comprises an outer hose, in whose lumen a fluid line is arranged that supplies fluid to the instrument tip. The hose conveys the fluid supplied to the instrument tip in the reverse direction back. The hose is held in a handle at its (proximal) end located away from the patient. A sleeve made of fiber-reinforced plastic serves this purpose and is characterized by a low thermal conductivity.

[0003] Furthermore, DE 10 20152005367 A1 uses the insulating properties of fibre-reinforced plastics in the so-called freeze tip.

[0004] An instrument of the first mentioned type is for example also known from EP 2 630 982. This instrument is provided with a plug having at its proximal end one or more pins which extend in parallel away from the plug housing. These pins are arranged to supply a cooling fluid to the instrument. A cable extends away from the plug with an electric plug which serves to supply power to the instrument. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] China Patent Publication No. 1480103 [Patent Document 2] DE 1020152005367 A1 [Patent Document 3] European Patent No. 2630982 Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present invention is to 2 and providing an instrument that can be easily manufactured and is therefore permanently reliable. [Means for solving the problem]

[0007] This object is solved by an ablation instrument and also in particular by a treatment device as claimed in claim 15.

[0008] As mentioned above, the ablation tool according to the invention can be a tool for affecting tissue by heat or cold. In either case, the tool comprises a hose surrounding a lumen, the hose configured closed at its distal end and connected at its proximal end to a plug. The plug can be configured to at least deliver liquid, gas or supercritical carbon dioxide (CO2). 2 ) to the ablation instrument, for which purpose a fluid line originating from the plug extends through the lumen of the hose.

[0009] The plug is CO 2The device comprises at least one pin connectable to a source, the pin having an inner channel that can be fluidly connected to the fluid line and that is closed at its outer end located away from the plug. Two ring grooves on the pin arranged at a distance from each other hold a seal, in particular a ring-shaped seal, for example an O-ring. The seal can be inserted into the ring groove as a separate component or can be connected to the pin in a material-bonding manner. For this purpose, the seal can be manufactured together with the pin in a co-extrusion process. Between the two O-rings, a radial opening is formed that leads into the channel.

[0010] According to the invention, the pin consists of a fiber-reinforced thermoplastic, in particular polycarbonate (PC), polyamide (PA), polybutylene terephthalate (PBT) or polyimide (PI) can also be considered as plastics. These plastics are preferably reinforced by so-called short fibers, which are embedded in the plastic and preferably regularly distributed in the plastic. The fiber percentage can be between 20% and 40% by weight, preferably 30% by weight. In particular glass fibers can be considered as fibers, in which case the fiber length is preferably less than 3 mm, even more preferably less than 2 mm or even less than 1 mm. CO 2 In addition, it is inert to CO 2 Other preferably non-metallic fiber materials that do not absorb can also be used. Fibers from organic materials can also be used, but preferably from inorganic materials. The thickness of the fibers is preferably about 5 μm to 10 μm, preferably about 10 μm.

[0011] Such fiber-reinforced plastics are highly resistant to CO under high pressure (>50 bar). 2It has been shown that the same plastic without fiber reinforcement can withstand long-term (more than 60 minutes) impacts of 10 ...

[0012] The electrical connection means that may be provided on the plug serves to supply electrical current to the electrodes that are optionally provided on the ablation tool. For example, such connection means may be formed by one or more contacts that may be provided on one or more pins of the plug. In a preferred embodiment, the connection means is formed by an electrical wire with the electrical plug. The electrical wire may be a cable that runs from the plug that establishes a fluid connection with the tool to another plug that has electrical contact pins that can be inserted into a generator that is provided for that purpose.

[0013] Preferably, the plug comprises a plug housing in which the plug unit is arranged. The plug unit is preferably constructed as a monolithic injection-molded part with a head arranged in the plug housing and at least one or more pins extending parallel to each other away from the plug housing. If only one pin is present, it can be constructed in a stepped manner to connect several fluid channels. The pin unit is formed monolithically together with the pin from the same fiber-reinforced thermoplastic without seams. The pin unit integrates all the necessary functional elements together with the gas joint for a fluid-tight connection of the hose and the fluid line and for gas-tight guidance of potentially present electric wires out of the lumen of the hose. In addition, it redirects the coaxial gas transport of the instrument to the parallel gas transport of the pin of the plug.

[0014] The material selection according to the invention makes it possible to provide a particularly small wall thickness, especially in the region of the groove of the respective pin, which can be smaller than the width of the respective groove measured in the pin longitudinal direction. On the other hand, it makes it easy to define a channel diameter which is larger than the wall thickness in the region of the groove. This avoids undesirable throttling effects in the gas path during gas supply to the instrument and thus a good cooling effect at its distal end.

[0015] Further details of advantageous embodiments of the invention are the subject of the figures, the drawings and the respective description or claims. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram of a treatment device having an ablation tool plugged into a socket of a supply device connected to a CO2 gas source. [Diagram 2] FIG. 2 is a separate perspective view of the ablation instrument according to FIG. 1. [Diagram 3] FIG. 3 is a partial enlarged view, cut longitudinally, of a pin of the plug according to FIGS. 1 and 2; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] FIG. 1 shows a treatment device 10 comprising an ablation tool 11 with a plug 12 at its proximal end. Also shown in FIG. 1 is a treatment device 10 that is configured to pump carbon dioxide (CO 2 ) from a storage device 14. 2 ) to a gas socket 15.

[0018] The ablation instrument is preferably configured as a disposable instrument that is not provided for multiple use on different patients and therefore for reconditioning, however, it can also essentially be designed as a reusable instrument.

[0019] The ablation instrument 11 comprises a flexible hose 16 which can be introduced into the patient, for example through a working channel of an endoscope, the proximal end 17 of the hose 16 terminating in and held in an air-tight manner within the plug 12. The hose encloses a lumen 18 which extends from the proximal end 17 to a distal end 19 at which the hose 16, and thus the lumen 18, are closed.

[0020] Inside the lumen 18, the instrument 11 and the distal end section 21 of the hose 16 are connected to a CO 2 A fluid line 20 is disposed in the plug 12 and functions to supply CO. A proximal end 22 of the fluid line 20 is held in a fluid-tight manner within the plug 12. The fluid line 20 has at its end a fluid line 22 operative to supply CO 2 and may include one or more exit openings to allow CO to exit. 2 It thereby expands and thereby absorbs heat, i.e., cools.

[0021] One or more electrodes 23, 24 may be arranged on the distal end section 21, which serve to supply electrical current and thus heat the biological tissue. The electrodes may be connected via respective electrical wires 25, 26 to a plug 27, which together with the electrical wires form an electrical connection means 28. The plug 27 may comprise one, two or more electrical contact pins 29, which serve to supply electrical current to the electrodes 23, 24 via the electrical wires 25, 26. In addition, one or more of the contact pins 29 may be configured and used for instrument identification.

[0022] The plug 12 of the device 11 according to the invention comprises a pin unit 30 having at least one, and preferably several pins 31, 32, 33 extending parallel to one another away from a headpiece 34, which pins are constructed seamlessly and monolithically with the headpiece.

[0023] The following description of the pin 32 in relation to figures 1 and 3 applies accordingly to the other pins 31, 33. The pin 32 comprises a longitudinal tubular base in which two ring grooves 35, 36 are arranged externally at an axial distance from each other. The ring grooves 35, 36 serve to seat sealing elements, e.g. O-rings 37, 38, by means of which the pin 32 is sealingly arranged in a corresponding jack 39 of the gas socket 15. The pin 32 surrounds a channel 40, which is closed at an end 41 located away from the plug 12. A radial opening 42 connects the channel 40 to the interior of the jack 39 when the plug 12 is inserted in the gas socket 15. The jack 39 is connected to the gas supply unit 13 via a fluid channel 39a, through which pressurized (e.g. between 40 bar and 70 bar) CO 2 is delivered. 2 is supplied.

[0024] The pin 32 has a wall thickness w1 of the ring groove 36 surrounding the channel 40 that is less than a wall thickness w2 measured away from between the ring grooves 35, 36. In addition, the wall thickness w1 is preferably less than the groove width b and less than the channel diameter d.

[0025] The channel 40 opens into a passage in the headpiece 34, which also forms a seat 43 for sealingly retaining the proximal end 22 of the fluid line 20. The fluid line 20 is sealingly retained against the seat 43 by a seal. A retaining piece 44 is secured to the proximal end 22 of the fluid line 20 by an adhesive.

[0026] Additionally, the headpiece 34 carries a gas fitting 45 arranged in an airtight manner on the side remote from the pins 31-33, for example on the plane of the headpiece 34 forming an attachment area 50. This attachment area 50 forms a seat for the gas fitting. The gas fitting guides the wires 25, 26 exiting the lumen 18 and provides a means for discharging the expanded CO 2 3, the gas connection 45 is provided with a channel 40' through which the lumen 18 is connected to the channel 40' of the pin 33. In addition, the gas connection 45 is provided with a seal or a sealed adhesive joint for the electric wires 25, 26 which serve to contact the electrodes 23, 24 and guide them out of the gas-conveying area of ​​the plug 12.

[0027] The plug 12 comprises a plug housing 47 which may consist of two housing shelves 48, 49 made of plastic, for example as shown in Figure 2. The headpiece 34 and the gas connector 45 are mounted within the plug housing 47. The pins 31, 32, 33 protrude from the housing 47.

[0028] The treatment device 10 described thus far operates as follows when using the ablation tool 11.

[0029] For devitalization of biological tissue, the ablation instrument 11 is penetrated with its distal end section 21 into the tissue to be devitalized, for example a small lung tumor, so that both electrodes 23, 24 are located inside the tumor. When the instrument 11 is activated, the gas supply unit 13 delivers carbon dioxide taken from the reservoir 14 under a controlled pressure in the range of 40 bar to 70 bar to the gas socket 15, here in particular to the central jack 39. Thereby, each gas delivery channel 39a terminates inside the jack 39 between two O-rings 37, 38 of the pin 32 inserted in the jack 39.

[0030] Through the radial openings 42 and channels 40, the carbon dioxide now flows towards the sheet 43 and from there through the fluid lines 20 to the distal end section 21 of the instrument, cooling the distal end section and therewith the electrodes 23, 24. 2 The fluid then passes from fluid line 20 into lumen 18, thereby expanding under significant cold conditions.

[0031] At the same time, the electrodes 23, 24 are supplied with a current via a plug 27 or another connection means 28, which flows through the tumor, thereby heating it. Thereby, the cooling of the electrodes 23, 24 avoids excessive heating, so that the maximum local temperature is not provided on the electrodes 23, 24, but at some distance relative to it. This treatment process may require a significant time phase, for example 15 minutes. Also, the therapist can combine several such treatments with each other, in that he treats each tumor several times or treats (ablates) additional tumors accordingly. This means that carbon dioxide flows through the channel 40 of the pin 32 under a pressure of about 40 bar to 50 bar or more, for a significant total duration that can significantly exceed one hour. This allows the carbon dioxide to diffuse into the plastic from which the pin 32 is made, which may reduce the tensile strength of the plastic. However, due to the fibers present in the plastic, especially glass fibers, the softening of the plastic, especially the expansion in the area of ​​the ring groove 36, is effectively suppressed. As a result, the pin 32 maintains its length. The pin does not expand longitudinally (in the direction of the channel 40) and there is no risk of it breaking in its areas of small wall thickness (eg in the area of ​​the ring groove 36).

[0032] In the concept according to the invention, a plug 12 for an ablation instrument 11 is provided, which, apart from potentially provided electrical wires 25, 26, is entirely made of plastic and can be produced rationally by economical production methods, for example injection moulding techniques. In particular, the pin unit 30 contributes thereto, on which the pins 31, 32, 33 as well as the seat 43 for the fluid line 20 and the connection surfaces for the gas joint 45, also made of plastic, are formed. In this configuration, the ablation instrument 11 is particularly suitable as a disposable instrument, the disposal of which does not require the disposal or recycling of valuable materials, but only plastic parts which can be produced rationally. [Explanation of symbols]

[0033] 10 Therapeutic Devices 11 Ablation Instruments 12 Plug 13 Gas supply unit 14 Storage Device 15 Gas Socket 16 Hose 17 Proximal end of hose 16 18 lumen 19 Distal end of hose 16 20 Fluid Lines 21 distal end section of hose 16 22 Proximal end of fluid line 23,24 electrode 25,26 Electric wire 27 Plug 28 Electrical connection means 29 Electrical contact pin 30 pin unit 31~33 pins 34 Headpiece 35,36 Ring groove 37,38 O-ring 39 Gas Socket 15 Jack 39a Fluid Channel 40 Channels 41 End of pin 32 42 Radial opening w1 wall thickness of ring groove 36 w2 wall thickness between ring grooves 35 and 36 b Groove width d Channel diameter of channel 40 43 seats 44 Holding piece 45 Gas Region 46 Adhesive 47 Housing 48,49 Housing shell 50 Gas joint 45 mounting area

Claims

1. An ablation instrument (11), comprising: a hose (16) surrounding a lumen (18), the hose (16) having a distal end section (21) and a proximal end (17), the hose (16) being configured closed at its distal end (19) and connected at its proximal end to a plug (12); a fluid line (20) extending through the lumen (18) from the plug (12) to the distal end section (21); having The plug (12) comprises at least one pin (32), the at least one pin (32) being a ２ a gas supply unit (13) that can be connected to said fluid line (20) and has an internal channel (40) connected to said fluid line (20); said pin (32) comprises two ring grooves (35, 36) spaced apart from each other, sealing rings (37, 38) are arranged in said ring grooves, and between said sealing rings (37, 38) a radial opening (42) is formed which leads to said channel (40); The pin (32) is made of a fiber-reinforced thermoplastic. Ablation instruments.

2. at least one electrode (23, 24) is arranged on the distal end section (21) of the hose (16), said at least one electrode (23, 24) being connected to an electrical connection means (28) provided on the plug (12), The ablation tool of claim 1 .

3. The plug (12) is characterized in that it comprises a plug housing (47) in which a pin unit (30) is disposed. The ablation tool of claim 1 .

4. characterised in that a number of pins (31, 32, 33) extending parallel to one another and seamlessly and monolithically made of the same fibre-reinforced thermoplastic are arranged on a pin unit (30), The ablation tool of claim 1 .

5. characterised in that the channel (40) arranged inside the pin (32) is closed at its free end (41), The ablation tool of claim 1 .

6. characterised in that the pin (32) has a wall thickness (w1) in the region of the groove (36) that is smaller than a wall thickness (w2) outside the groove (36), The ablation tool of claim 1 .

7. characterised in that the pin (32) has a wall thickness (w1) in the region of the groove (36) that is less than half the wall thickness (w2) outside the groove (37), The ablation tool of claim 6.

8. characterised in that the pin (32) has a wall thickness (w1) in the region of the groove (36) which is less than a width (b) of the groove (36) measured in the longitudinal direction of the pin, 8. An ablation instrument according to claim 1, 6 or 7.

9. The pin unit (30) is characterized in that it comprises a seat (43) for sealingly mounting the fluid line (20).

5. An ablation tool according to claim 3 or 4.

10. characterised in that the pin unit (30) comprises a mounting area (50) for mounting a gas connection element (45) comprising a seat for sealingly mounting the proximal end (17) of the hose (16), 5. An ablation tool according to claim 3 or 4.

11. The plastic is PA, PC or PBT. The ablation tool of claim 1 .

12. characterised in that the plastic contains a fibre proportion of 20% to 40% by weight, preferably 30% by weight. The ablation tool of claim 1 .

13. The fibers present in the plastic are glass fibers. The ablation tool of claim 1 .

14. Characterized in that the fibers present in the plastic have a length of less than 3 mm, preferably less than 2 mm, and more preferably less than 1 mm.

14. An ablation instrument as claimed in claim 1 or 13.

15. A therapeutic device (10) comprising an ablation device (11) according to any one of claims 1 to 7, a gas storage device (14) and a CO gas storage device (15) adapted for the plug (12) of the ablation device (11). ２ and a gas supply unit (13), the socket supplying the CO ２ connected to a gas supply unit (13), treatment equipment.

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