HIGH-FREQUENCY ELECTRODE FOR USE IN A SURGICAL HAND DEVICE, ELECTRODE INSTRUMENT AND RESECTOSCOPE

Description

[0001] The invention relates to a high-frequency electrode for use in a surgical handheld device according to the preamble of claim 1. Furthermore, the invention relates to an electrode instrument for use in a surgical handheld device according to claim 10 and a resectoscope according to claim 11. High-frequency electrodes for handheld devices, in particular resectoscopes, of this type are primarily used in urology for electrosurgical procedures in the bladder, prostate, and urethra. These high-frequency electrodes can also be used for other surgical and orthopedic treatments or procedures. Typically, these electrodes are used for the resection, vaporization, and electrocoagulation of tissue, e.g., tissue in the lower urinary tract. For this purpose, the handheld devices or resectoscopes comprise a high-frequency electrode or an electrode instrument of this type, which is located within a shaft of the handheld device.The resectoscope is mounted so that it can be moved longitudinally and rotated. The surgical high-frequency electrode is arranged at a distal working end of the electrode instrument, e.g., in the form of a loop or a button.

[0002] Such electrodes can be monopolar or bipolar. Depending on the application and design, the electrodes are supplied with electrical energy or a high-frequency voltage via electrical conductors. The high-frequency current is supplied via the handheld device or the resectoscope by a high-frequency generator. If the electrode is monopolar, a neutral electrode is placed on the patient. Alternatively, the neutral electrode can also be integrated into the resectoscope. In this case, the shaft, the transporter, and the optics serve as the neutral electrode of an electrical potential.

[0003] Applying a standard high-frequency voltage to the electrode generates a plasma of electrically charged particles around the electrode or parts of it. This plasma is localized directly at the electrode and exhibits a high temperature and energy density, making it particularly well-suited for the applications mentioned above. For vaporization and electrocoagulation of tissue, it is essential that the plasma is generated at a specific area of ​​the electrode, allowing the practitioner to apply the electrode with pinpoint accuracy.

[0004] With known high-frequency electrodes, a plasma sometimes forms that tends to orient itself towards the electrode's electrical conductors. This makes targeted electrode placement difficult and reduces the plasma density at the electrode itself. Ideally, the plasma forms in a lower or middle region of the electrode where it is in contact with the tissue. Plasma formation in an upper region of the electrode, where the electrical conductors are located, proves disadvantageous for surgical applications.

[0005] For the treatments mentioned above, it is advantageous for the electrode to have the largest possible active area. However, the size of this area is limited by the dimensions of the application area, and larger electrodes require higher energy to ignite the plasma. Increased heat, however, has a detrimental effect on the area being treated. Furthermore, a larger electrode reduces the ignition speed. Relevant state-of-the-art information can be found in US 2018 / 344382 A1, WO 97 / 07747 A1, US 6 730 081 B1, US 6 544 260 B1, and US 2017 / 100190 A1.

[0006] The invention is based on the objective of creating a high-frequency electrode, an electrode instrument and a resectoscope in which the plasma can be better localized at the electrode, thereby maximizing the area in tissue contact and simultaneously reducing the energy required to ignite the plasma.

[0007] A solution to this problem is described by the features of claim 1. Accordingly, the high-frequency electrode for use in a surgical handheld device, in particular a resectoscope, is designed in the shape of a toroid. This toroidal or donut-shaped electrode has an outer circumference and an inner circumference. The electrode body describes a closed ring structure. To use this electrode, for example for vaporization, resection, or electrocoagulation, the toroid is moved with its lower half over the tissue to be treated in a patient. Due to its toroidal shape, this high-frequency electrode has a large active surface area, which is, however, reduced by the central opening. This reduced active surface area means that less electrical energy is required to ignite the plasma than with known full-surface electrodes.This also allows the ignition speed to be increased or the ignition time to be reduced. Another advantage of the toroidal or donut-shaped electrode is that bubbles in the purge fluid, which are generated by the plasma and impair visibility, can be controlled and drained through the electrode's opening. This removal of the bubbles improves visibility in front of the optics.

[0008] Preferably, the toroidal electrode for generating a plasma is connected to an electrical conductor, via which the electrode can be coupled to a high-frequency generator. In this electrode, the electrical conductor is coupled to a lower region or half of the toroid. This lower region is electrically conductive. The complementary upper region or half of the electrode can be electrically conductive or insulating. This ensures that the electrical energy is deposited precisely where the plasma is to be generated. The electrical conductor can, for example, be routed to the high-frequency generator via a shaft of the handheld device, particularly the resectoscope. The electrical conductor can be integrally connected to both the high-frequency electrode and the handheld device, or it can be connected to the handheld device and / or the high-frequency electrode via a plug-like connector.It is conceivable that the high-frequency electrode could have one or two conductors, allowing it to be connected to the handheld device in a plug-like manner. This would be particularly advantageous for maintenance and cleaning purposes.

[0009] The invention provides that the toroidal electrode for generating a plasma has two electrical conductors, each contacting an electrical pole of the electrode and each capable of being coupled to a high-frequency generator, wherein the electrical poles of the electrodes are electrically insulated from each other by an insulating element. In this bipolar electrode, the electrical conductors each lead to a pole on the electrode. The high-frequency electrode is thus divided into two poles. Preferably, one pole is positioned on a lower surface and the other pole on a higher surface of the electrode. The insulating element is located between the poles. However, it is also conceivable that the poles on the electrode are divided differently. For example, it is conceivable that one pole on the lower surface of the electrode is significantly larger than the second pole, which extends only in a ring-like fashion on the higher surface of the electrode.This special electrode design allows for particularly precise localization and application of the plasma intended for surgical use. Furthermore, it is conceivable that the other or second pole, or neutral electrode, could be located on one of the two support arms of the electrode instrument. Thus, it is possible that the two support arms or forked tubes of the electrode could also serve as the return and / or neutral electrode.

[0010] Furthermore, according to the invention, the electrode can be attached to the handheld device, in particular to an electrode instrument, preferably detachably, via the at least one electrical conductor and / or via at least one retaining element. In addition to the at least one electrical conductor, a further element, for example made of a metal or an insulator, can thus ensure the stability of the electrode on the handheld device or the electrode instrument. Particularly during use, the electrode is subjected to increased mechanical tensile and compressive forces. The retaining element and the at least one electrical conductor ensure that the electrode does not lose its position relative to the handheld device, even under increased mechanical forces. The retaining element can also be designed like a plug, so that a detachable connection or coupling connection with the handheld device is possible.

[0011] The invention provides that at least one, preferably two, electrical conductors contact the toroid on its inner surface. This positioning of the conductors on the inner circumference of the toroid prevents them from interfering with treatment. Because the electrical conductors are located on the inner circumference, the outer circumference and the underside of the toroid can be used for cutting or vaporizing the tissue.

[0012] The invention provides that a cross-section parallel to a radial axis of the toroid is elliptical, oval, circular, triangular, rectangular, preferably square, trapezoidal, polygonal, or the like. These different cross-sections allow for the generation of different plasma densities on the surface of the toroid. In particular, shapes with acute angles allow for the generation of a particularly high plasma density, which is advantageous for certain applications, such as tissue cutting. Similarly, large areas allow for the particularly effective vaporization or coagulation of tissue regions.

[0013] Furthermore, it is conceivable that the outer circumference of the toroid could be elliptical, oval, or circular. The shape of the circumference can also optimize its use for specific surgical procedures. Depending on the area to be treated and the type of treatment, it may be advantageous to use an elliptical, oval, or circular toroid.

[0014] A particular embodiment of the present invention may provide that a ring-shaped projection, preferably an edge, is formed around an outer circumference of the toroidal surface. This projection facilitates plasma ignition or enables particularly rapid ignition with low energy expenditure. Due to the higher electric field strength at this ring-shaped projection, the plasma ignites quickly, allowing the electrode to be used for particularly short periods. It is also conceivable that this ring-shaped projection is only formed as an edge in certain areas or is positioned at a different location on the toroidal surface.

[0015] Furthermore, it is conceivable that a first electrical conductor is assigned to a lower section of the toroid, forming a first electrical pole, and a second electrical conductor is assigned to an upper section of the toroid, forming a second electrical pole, wherein the lower and upper sections are of the same or different surface areas. In particular, the lower section is either larger or smaller in area than the upper section.

[0016] Furthermore, it is conceivable that an outer, and especially a central, diameter of the toroid is 2 to 5 times, and in particular 2.5 to 4, or 3 times larger than an inner, and in particular a central, diameter of the toroid. Other diameter ratios are also conceivable. For example, the toroid may be designed to be almost ring-shaped or nearly completely closed. Depending on the intended use, certain geometries may be particularly advantageous.

[0017] The toroid is primarily made of stainless steel, titanium, platinum-iridium, or platinum-tungsten. It is also conceivable that the toroid could be constructed from another electrically conductive material. The electrical insulator could be made of a plastic or a ceramic.

[0018] An electrode instrument for solving the aforementioned problem has the features of claim 10. Accordingly, it is provided that the electrode instrument for use in a surgical hand device, in particular in a resectoscope, has an elongated shaft section with two support arms through which at least one conductor extends, which is connected or connectable at the distal end of the instrument to a high-frequency electrode according to claims 1 to 9.

[0019] The high-frequency electrode is arranged between the distal ends of the support arms. A resectoscope for solving the aforementioned problem has the features of claim 11.

[0020] Preferred embodiments of the invention are described in more detail below with reference to the drawing. This drawing shows: Fig. 1 a schematic representation of a surgical hand instrument, in particular a resectoscope, Fig. 2 an embodiment of a high-frequency electrode, Fig. 3 4 another embodiment of a high-frequency electrode, Fig. 5 another embodiment of a high-frequency electrode, Fig. 6 another embodiment of a high-frequency electrode, and Fig. 7 another embodiment of a high-frequency electrode.

[0021] In the Fig. 1A resectoscope 10 is shown as an example of a surgical handheld device. This resectoscope 10 essentially consists of a transporter 11, a handle 12, and a shaft 13, which is inserted into a corresponding body orifice to treat a patient. In the embodiment shown here, the shaft 13 comprises an outer shaft tube 14, an optic 15, and an electrode instrument 16. The optic 15 consists of a long tube in which lenses or optical fibers can be arranged to observe the treatment area at the distal end of the shaft 13 through an eyepiece 17 located proximally to the shaft 13. For a more detailed description of a resectoscope, reference is made to the known prior art.

[0022] The electrode instrument 16 essentially consists of a high-frequency electrode 18 and at least one electrical conductor 19. The at least one electrical conductor 19 supplies the high-frequency electrode 18 with a high-frequency voltage and, if necessary, serves as a holder for the electrode 18 on the electrode instrument 16. The electrical conductor 19 extends from the distal end of the resectoscope 10 through the shaft 14 and is connected via further conductors to a high-frequency generator (not shown) for generating the high-frequency electromagnetic energy. The two conductors 19, 29 can be guided through the two support arms 29, 30 or through the forked tubes of the electrode instrument 16. Fig. 2 )

[0023] Tissue can be manipulated using the high-frequency electrode 18. For this purpose, the high-frequency electrode 18 can be configured as either a monopolar or bipolar electrode. In the case of a bipolar electrode, it is connected to two electrical conductors 19 and 20. In the embodiment of a monopolar electrode, the electrode 18 is connected to only one electrical conductor 19. A further neutral electrode is attached to the patient or integrated into the resectoscope (shaft, transporter, optics; if all components are at the same electrical potential, this results in a low current density due to the large surface area). By applying electrical energy to the high-frequency electrode 18, a plasma is generated at the electrode 18, which is then used to manipulate tissue by corresponding movement of the electrode instrument 16.

[0024] The high-frequency electrode 18 according to the present invention is designed as a toroid 21. In the Fig. 2 An example of a toroid 21 with a circular cross-section is shown. This toroid 21 is electrically connected to the energy source via two electrical conductors 19, 20 of the electrode instrument 16. Alternatively, one of the conductors 19, 20 could be designed as a holding element.

[0025] The toroid 21, or high-frequency electrode 18, has a lower region 22 and an upper region 23. These regions 22 and 23 can be of different sizes. In the embodiment shown here, the electrical conductor 19 leads to the lower region 22, and the electrical conductor 20 leads to the upper region 23 of the toroid 21. It is also conceivable that the upper region 23 is fixed by the additional holder. In a bipolar electrode, an insulator is provided between the electrically conductive regions 22 and 23 to isolate the two electrical poles from each other. This particular embodiment of the high-frequency electrode 18 allows a particularly large plasma to be generated at the lower region 22 of the electrode 18, enabling the removal of a large amount of tissue in a short time.The toroidal shape of the high-frequency electrode 18 allows the active surface area of ​​the electrode 18 to be kept small, so that little heat or electrical energy is required to ignite the plasma. Furthermore, this shape is particularly advantageous for rapid plasma ignition.

[0026] The ratio between the outer circumference of the "donut-shaped" high-frequency electrode 18 and its inner circumference can assume any value. Depending on the type of treatment or application, differently dimensioned toroids 21 can be used. In the Figs. 3 to 7 Various toroidal structures are depicted. For example, in the Fig. 3 An example of a high-frequency electrode 18 is shown, in which a cross-section of a toroid 24 is rectangular or square. In the case of the Fig. 4 The illustrated toroid 25 has a trapezoidal cross-section. The embodiment shown in the Fig. 5Figure 26 shows a toroid 26 with a triangular cross-section. The embodiment of a toroid 27 according to Figure 27 also shows a triangular cross-section. Fig. 6 In this embodiment, however, the triangle is tilted in such a way that one point faces outwards. In the Fig. 7 Another embodiment of a toroid 28 is shown. Due to the different shapes, different plasmas form at the high-frequency electrode 18 because of the different electric field strengths. Depending on the requirements, a particularly advantageously shaped electrode 18 can thus be selected. It should be explicitly noted that the selection of toroid shapes shown here is not exhaustive. Rather, it is conceivable that the toroids could assume almost any shape.

[0027] An embodiment of the invention, not shown, may provide that an edge or a ring-like border is arranged on an outer surface of the toroid 21. This edge promotes the formation of a plasma, which on the one hand reduces the ignition energy and on the other hand shortens the ignition time.

[0028] The high-frequency electrode 18 according to the invention can be connected to the resectoscope 10 via a plug-in connection together with the electrode instrument 16. Likewise, it is conceivable that the electrode 18 can be connected to the electrode instrument 16 via a plug-in connection. This is particularly advantageous for maintenance and cleaning purposes.

[0029] It should be expressly noted that the use of the high-frequency electrode 18 is not limited to urological applications. Rather, it is also conceivable that this electrode 18 could be used for orthopedic or other surgical or medical applications. Reference symbol list

[0030] 10 Resectoscope 29 support arm 11 carrier 30 support arm 12 Handle unit 13 shaft 14 shaft tube 15 optics 16 Electrode instrument 17 eyepiece 18 High-frequency electrode 19 Electrical conductor 20 Electrical conductor 21 Toroid 22 Lower area 23 Upper area 24 Toroid 25 Toroid 26 Toroid 27 Toroid 28 Toroid

Claims

1. A radiofrequency electrode (18) for use in a surgical handheld device, more particularly in a resectoscope (10), wherein the radiofrequency electrode (18) is able to be supplied with electric power by way of at least one electrical conductor (19, 20), wherein the radiofrequency electrode (18) has the shape of a toroid (21, 24, 25, 26, 27, 28), wherein a cross section parallel to a radial axis of the toroid (21, 24, 25, 26, 27, 28) is elliptical, oval, circular, triangular, rectangular, square, trapezoidal or polygonal, and wherein the electrical conductors (19, 20) contact the toroid (21, 24, 25, 26, 27, 28) at an inner side, characterized in that the toroidal electrode (18) for generating a plasma comprises two electrical conductors (19, 20), said electrical conductors each contacting an electrical pole of the electrode (18) and being able to be coupled to a radiofrequency generator, wherein the electrical poles of the electrode (18) are electrically insulated from one another by way of an insulator element.

2. The radiofrequency electrode (18) as claimed in claim 1, characterized in that at least one electrical pole, more particularly a neutral electrode and / or a return electrode, of the electrode (18) is formed by a support arm (29, 30) or a fork tube of the electrode (18).

3. The radiofrequency electrode (18) as claimed in any one of the preceding claims, characterized in that the electrode (18) is fastened, preferably detachably fastened, to the handheld device, in particular to an electrode instrument (16), via the at least one electrical conductor (19, 20) and / or at least on a holding element.

4. The radiofrequency electrode (18) as claimed in any one of the preceding claims, characterized in that the two electrical conductors (19, 20) contact the toroid (21, 24, 25, 26, 27, 28) at an inner side.

5. The radiofrequency electrode (18) as claimed in any one of the preceding claims, characterized in that an outer circumference of the toroid (21, 24, 25, 26, 27, 28) has an embodiment that is elliptical, oval or circular.

6. The radiofrequency electrode (18) as claimed any one of the preceding claims, characterized in that a ring-like protrusion, preferably an edge, is formed around an external circumference of the toroid surface.

7. The radiofrequency electrode (18) as claimed in claim 1, characterized in that a first electrical conductor (19) is assigned to a lower section of the toroid (21, 24, 25, 26, 27, 28) and this section forms a first electrical pole and a second electrical conductor (20) is assigned to an upper section of the toroid (21, 24, 25, 26, 27, 28) and this section forms a second electrical pole, wherein the lower and the upper section have the same or a different embodiment in terms of area, in particular wherein the lower section is larger or smaller than the upper section in terms of area.

8. The radiofrequency electrode (18) as claimed in any one of the preceding claims, characterized in that an outer diameter, in particular mean outer diameter, of the toroid (21, 24, 25, 26, 27, 28) is 2 to 5 times, more particularly 2.5 to 4, or 3 times larger than an inner diameter, in particular mean inner diameter, of the toroid (21, 24, 25, 26, 27, 28).

9. The radiofrequency electrode (18) as claimed in any one of the preceding claims, characterized in that the toroid (21, 24, 25, 26, 27, 28) substantially consists of stainless steel, titanium, platinum iridium or platinum tungsten and an electrical insulator consists of a ceramic or a plastic.

10. An electrode instrument (16), more particularly a monopolar or bipolar electrode instrument (16), for use in a surgical handheld device, more particularly in a resectoscope (10), wherein the electrode instrument (16) comprises an elongate shaft section (13) with two support arms (29, 30), through which at least one conductor (19, 20) extends, the latter forming a radiofrequency electrode (18) as claimed in claims 1 to 9, which is able to be impinged with a radiofrequency current, at the distal end of the electrode instrument (16), said radiofrequency electrode being arranged between the distal ends of the support arms (29, 30).

11. A resectoscope (10) comprising an electrode instrument (16) as claimed in claim 10.