Electrodes for handheld electrosurgical instruments and methods for manufacturing electrodes - Patents.com

Abstract

To provide a method for manufacturing an electrode and an electrode which can be used particularly efficiently and can be manufactured in a particularly cost-effective manner.SOLUTION: The invention is achieved in that an electrode (16) for an electrosurgical hand instrument comprises an electrically conductive wire consisting of a plurality of sections. In this case, two sections of the wire (26) R1 and L1, which are directly adjacent to two ends of the wire, are aligned parallel to each other as well as straight. Furthermore, the first two sections R1 and L1 are adjoined by two second sections R2 and L2 which are also aligned parallel to each other as well as straight. Thereby, section R2 directly adjoins section R1, and section L2 directly adjoins section L1. The two sections R2 and L2 are in turn connected to each other by a further section C.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electrode for an electrosurgical handheld instrument according to claim 1. Furthermore, the present invention relates to a method for manufacturing an electrode according to claim 9. [Background technology]

[0002] Electrosurgical handheld instruments of the aforementioned type, particularly resectoscopes, are primarily used for electrosurgical work in urology. In this context, these instruments are typically used for resection and vaporization of tissue, for example, tissue of the lower urinary tract. For this purpose, handheld instruments, particularly resectoscopes, can be equipped with a longitudinally displaceable electrode carrier, the distal working tip of which can be advanced from the distal end of the instrument shaft of the handheld instrument after insertion of the instrument into the body of the subject. An electrosurgical electrode is disposed at the distal end of the electrode carrier. This electrode may be in the form of, for example, a loop, which, depending on the instrument configuration, can be pulled or pushed through tissue to manipulate it.

[0003] In these applications, a high-frequency current is applied to the electrode. It is important to ensure that the electrode does not come into electrical contact with the handpiece shaft tube. If such electrical contact occurs, a short circuit can occur, causing device failure or unintended trauma to the treated body. To prevent such short circuits, the handheld device includes an electrically insulating insulating insert, also called an insulating tip, in the distal end region. In this case, the insulating insert can be attached either to the inner shaft or shaft tube through which the electrode carrier is guided, or to the outer shaft of the instrument. Because such handheld instruments are also designed for multiple use and therefore require periodic sterilization or autoclaving, the insulating insert is designed to be removable for cleaning.

[0004] In the case of the handheld instruments described herein for minimally invasive treatment of patients, the objective is to minimize the size or cross-section of the instrument as much as possible in order to minimize trauma to the patient during the treatment. Likewise, the objective is to perform the procedure in a particularly efficient manner. For efficient surgery, the selection of electrodes is crucial. Only by using appropriate application-specific electrodes can optimal treatment goals be achieved. In particular, the effective cross-sectional area of ​​the electrode or working instrument relative to the cross-sectional area of ​​the instrument can be crucial. However, the effective cross-sectional area or size of the electrode is limited by the shape and diameter of the shaft of the electrosurgical handheld instrument. Therefore, it is not practical for the effective cross-sectional area of ​​the electrode to be larger than the cross-sectional area of ​​the outer periphery of the shaft. However, known devices do not optimally utilize the space available for the electrodes. Approaches to more efficiently utilize the available space require highly complex electrode shapes, which, on the one hand, are highly complex and expensive to manufacture, and, on the other hand, require significant efforts in quality control. Summary of the Invention

[0005] The invention is therefore based on the problem of creating a process for producing electrodes and electrodes that can be used particularly efficiently and that can be produced in a particularly cost-effective manner.

[0006] A solution to this problem is described in claim 1. According to this claim, an electrode for a handheld electrosurgical instrument is provided that includes a conductive wire consisting of multiple sections. Two sections R1 and L1 of the wire, directly adjacent to the two ends of the wire, are aligned parallel to each other and straight. Two second sections R2 and L2, also aligned parallel to each other and straight, are adjacent to the two first sections R1 and L1. Thus, section R2 is directly adjacent to section R1, and section L2 is directly adjacent to section L1. The two sections R2 and L2 are connected to each other by a further section C. The fact that a continuous wire has a mirror-symmetrical structure and always exhibits shape changes in only one spatial dimension makes the electrode particularly easy to manufacture. The fact that the electrode does not have a shape that changes direction in multiple dimensions from one section to the next particularly simplifies both production and quality control. Quality control is simplified since bending in only one spatial direction can be particularly easily checked in an automated or partially automated manner, for example by means of a camera system or a profile projector. This simplification of the structure of the electrode according to the invention means in particular that production can be carried out particularly cost-effectively.

[0007] Preferably, the length of sections R2, L2 is provided to be between 0.7 mm and 1.7 mm. The wire thickness of sections R1 and L1 and / or sections R2 and L2, and preferably also the wire thickness of the further sections, may be between 0.2 mm and 1.0 mm. This dimension has been found to be particularly advantageous for an efficient treatment of the patient and for a particularly cost-effective manufacture of the electrode.

[0008] Preferably, the present invention further provides that the two second sections R2 and L2 form an angle α of 35° to 120° with the first sections R1 and L1, preferably 70°, 45°, or 110°. Depending on the type of application of the electrode, different angles can be selected between the two pairs of sections. Sections R1 and R2 and sections L1 and L2 each lie in a plane, which are aligned parallel to one another. By shaping various sections in this way according to the present invention, a large number of different electrode shapes can be produced in a particularly simple and therefore inexpensive manner. Furthermore, other embodiments of the present invention may provide that the bending radii between sections R1 and R2 and between sections L1 and L2 are between 0.1 mm and 1 mm.

[0009] In particular, the invention provides that section C between sections R2 and L2 has a radius of 2.0 mm to 3.6 mm, preferably 2.8 mm. This loop-shaped electrode shape is particularly versatile and also exhibits high stability. It is further conceivable that section C is straight and aligned perpendicularly to sections R2 and L2. Alternatively, it is conceivable that section C has a V-shape or is trapezoidal in shape. Section C essentially corresponds to the section of the electrode that manipulates the tissue. By a corresponding movement of the electrode carrier, the electrode with section C is pulled or pushed through the tissue to be manipulated.

[0010] Another advantageous embodiment of the present invention may provide that sections R2, L2, and C lie in one plane. Depending on the application of the electrode, it may be advantageous for the sections to have different angles. By using the segment shapes described herein that can be bent into sections, electrodes of various shapes can be easily produced using simple means. By varying the aforementioned lengths and angles, a variety of different shapes and sizes can be produced without having to adapt the manufacturing process for this purpose.

[0011] It is also conceivable that section C is preferably designed as a roller electrode in that the hollow cylinder is inserted into straight section C. The hollow cylinder can have a cylindrical or barrel shape. The hollow cylinder can have a cylindrical or barrel shape.

[0012] A method for solving the above problem is described by the means of claim 9. It is therefore provided that several steps are performed consecutively to manufacture an electrode for an electrosurgical handheld instrument according to claim 1. In a first step, a straight wire is initially deformed to form a central section C. To this end, two free wire ends of the wire are bent toward each other so that they are parallel to each other. Then, two wire ends are bent in the same parallel direction to section C, and the remaining free wire ends form sections R1 and L1 (step 2). These deformation steps generalize or standardize the manufacture of electrodes. By slightly varying the aforementioned steps, a large number of different electrodes can be manufactured, and these electrodes can be formed in different ways depending on the field of application. The simple one-dimensional deformation steps of the aforementioned sections make it possible to avoid the use of complex tools. This simplification of manufacture makes the process particularly cost-effective.

[0013] In particular, it is envisaged that the two wire ends are bent relative to section C into sections L1 and R1 at angles between 35° and 120°, preferably 45°, 90° or 110°. By choosing these angles, any application of the electrode can be realised. Furthermore, it is also possible to optimise the electrode for other, possibly new, applications.

[0014] Preferably, in step 2, two further parallel straight sections L2 and R2 are formed between section C and the two parallel straight sections L1 and R1, and it is provided that the two wire ends are bent relative to section C so that these sections L2 and R2 lie in the same plane as sections L1 and R1. Thus, sections R2 and L2 can lie in the same plane as section C, and sections L1 and R1 can lie in the same plane as sections R2 and L2. Thus, a total of five sections are arranged in only two planes, which allows for a particularly simple manufacturing process in two steps. This is particularly advantageous both in terms of manufacturing costs and in terms of checking or guaranteeing the quality of the electrodes.

[0015] The method according to the present invention may provide that in step 1, section C between sections R2 and L2 is formed in an application-specific manner. Thus, section C may be circular, semicircular, elliptical, polygonal, rectilinear, V-shaped, etc. Section C may also be occupied by further components such as rollers, pins, buttons, etc.

[0016] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings. [Brief explanation of the drawings]

[0017] [Figure 1] 1 shows a schematic diagram of a handheld surgical device, specifically a resectoscope. [Figure 2] A side view of the electrode is shown. [Figure 3] 3 shows a front view of the electrode according to FIG. 2. [Figure 4] 10 shows a side view of another embodiment of an electrode. [Figure 5] 5 shows a front view of the electrode according to FIG. 4. [Figure 6] 10 shows a side view of another embodiment of an electrode. [Figure 7] 7 shows a front view of the electrode according to FIG. 6. [Figure 8a] 1 shows a depiction of a wire. [Figure 8b] 1 shows step 1 of the electrode manufacturing process. [Figure 8c] Step 2 of the electrode fabrication process is shown. DETAILED DESCRIPTION OF THE INVENTION

[0018] 1 shows a schematic cross-sectional side view of a resectoscope generally designated 10. The resectoscope 10 has a resectoscope shaft 11, which includes an outer shaft 12 or sheath tube, as shown. A tubular inner shaft 13 extends within the outer shaft 12. An electrode array 14 and illustrated optics 15 are shown within the inner shaft 13. Additionally, other elements not shown may be located within the resectoscope 10, such as separate irrigation tubing.

[0019] The electrode array 14 has at its distal end an electrosurgical tool or electrode 16. The electrode 16 shown here is shown as a loop, but may also be formed as a button or the like.

[0020] The electrode holder 14 can be forced axially in the distal and proximal directions by actuating the handle 19. Doing so pushes the electrode holder beyond the distal ends of the inner shaft 13 and outer shaft 12. This allows the surgeon to manipulate tissue further away from the tip of the resectoscope. Furthermore, for this purpose, the inner shaft 13 and / or the electrode carrier 14 can be mounted rotatably about their longitudinal axes. To manipulate tissue, a high frequency current is applied to the electrode 16.

[0021] The resectoscope 10 shown in FIG. 1 has a passive transporter in which the carriage 20 is moved distally relative to the distal first handle portion 21 by relatively moving the handle portions 21 and 22, which are located proximally on the resectoscope shaft 11, against a spring force applied by a spring bridge 23. When the carriage 20 is displaced distally relative to the handle portion 21, the electrode carrier 14 is displaced distally in a manner not shown. When the load on the handle portions 21, 22 is relieved, the spring force generated by the spring bridge 23 pushes the slide 20 back to its initial position and pulls the electrode carrier 14 proximally. When the slide 20 is moved rearward, an electrosurgical procedure can be performed with the electrode 16 without any manual force by the surgeon, i.e., passively.

[0022] For targeted treatment with the electrodes 16, the optical system 15 is positioned to allow the surgeon an optimal view of the surgical field. For this purpose, the resectoscope 10 has an eyepiece 24 at its proximal end, which is connected to the optical system 15. Alternatively, it is conceivable that a camera is arranged on the resectoscope 10 instead of the eyepiece 24.

[0023] The following figures show several embodiments of the electrode 16, all of which follow the same structure. For example, each electrode has first sections R1 and L1, which are equal in length and oriented parallel to one another. These first sections R1 and L1 are coupled to the distal end of an electrode support tube. This coupling to the electrode support tube stabilizes the electrode 16 and applies electrical energy to the electrode. The first sections R1 and L1 are followed by two second sections R2 and L2, which are also formed with the same length and aligned parallel to one another. The transition from the first sections R1 and L1 to the second sections R2 and L2 occurs in one plane, meaning that the manufacturing process is particularly simple and does not require complex tooling (see FIGS. 2-7).

[0024] In the example embodiment shown in Figures 2 to 5, the second sections R2 and L2 are inclined at angles of 90° and 45° relative to the first sections R1 and L1, respectively, and it is envisaged that this angle α may take a value between 35° and 120°, preferably 45°, 90° or 110°, or any other angle.

[0025] Section C is located between the two second sections R2 and L2. This section C connects the two second sections R2 and L2 and is formed as a loop in the embodiment shown in FIGS. 2 to 5. The shape of section C can also be varied, for example, it can have a larger or smaller radius of curvature. In this embodiment, section C is in the same plane as sections R2 and L2. To perform the procedure, depending on the type of resectoscope 10, the electrode 16 is pulled or pushed through the tissue to be treated by section C. For this purpose, it is preferably provided that the wire 26 of the electrode 16 has a circular cross section.

[0026] 6 and 7 show a so-called roller electrode 16. Like the previous electrode 16, this electrode 16 also consists of two first sections R1 and L1 and second sections R2 and L2 adjacent to the first sections R1 and L1 and angled relative to them. Between the two second sections R2 and L2 is located a trapezoidal section C on which a roller 25 is positioned. This roller 25 is used to manipulate the tissue to be manipulated during the procedure.

[0027] In addition to the example embodiments shown here, other configurations of the electrodes 16 are also possible. However, it is important that all electrodes 16 consist of a single wire 26 from which the aforementioned sections are formed, with only one change of direction between the sections in one plane at any one time. This prevents the electrodes 16 from adopting complex shapes that are particularly difficult to manufacture and whose quality is particularly difficult to control. The structure described here consists of three different sections, which means that production can be standardized, resulting in a very cost-effective manufacturing process.

[0028] 8a-8c show highly schematic sketches of a manufacturing process for producing an electrode 16 according to the present invention. Thus, in a first step, a straight wire 26 (FIG. 8a), which may already have the entire length of the electrode 16 or longer, is first bent in the middle so that two sections R1 and L1 have the same length and are aligned parallel to each other (FIG. 8b). Section C, which connects the two sections R1 and L1, can be bent around a certain shape, thereby determining the shape of section C. Section C can then be bent around the shape of section L1. Thus, this first forming step of the wire 26 is performed in one plane. A second forming step of the wire 26 is performed in a plane oriented transverse to the plane determined by section C. As shown in FIG. 8c, in a second step, sections R1 and L1 are bent evenly transverse to section C, maintaining their parallel orientation. In the embodiment of the method shown in FIG. 8c, the bending is performed so that straight, parallel sections remain between section C and sections R1 and L1. These sections form second sections R2 and L2. By varying the lengths of these sections R2 and L2, and also by varying the shape of section C, the shape or effective cross-sectional area of ​​the electrode can be varied. If necessary, the lengths of sections R1 and L1 can be adjusted to correspond to the dimensions of the electrosurgical handheld instrument, even after the manufacturing process is complete. Similarly, the free ends of sections R1 and L1 may be provided with additional contact means to improve electrical contact to the electrode support tube.

[0029] This means that essentially only two bending steps in two planes are required to manufacture the electrode 16. This not only makes the manufacture of the electrode 16 particularly easy, but also makes it easy to check the quality of the electrode 16. [Explanation of symbols]

[0030] 10 Resectoscope 11 Resectoscope shaft 12 outer shaft 13 Inner shaft 14 Electrode Carrier 15 Optical system 16 electrodes 17 Guide Elements 18 Longitudinal Axis 19 Handle 20 slides 21 Handle 22 Handle 23 Spring Bridge 24 eyepiece 25 rolls 26 wires R1 First Section R2 Second Section L1 First Section L2 Second Section C. Central Section α angle

Claims

1. a tubular shaft (13); a handle portion (21, 22) disposed proximally of the shaft (13); an electrode (16) formed by a conductive wire (26) disposed within said shaft (13); A resectoscope (10) comprising: The electrode (16) First sections (R1, L1) extending along the longitudinal direction of the shaft (13) and arranged parallel to each other with a gap therebetween; a second section (R2, L2) provided continuously with the first section (R1, L1) at a distal end opposite the proximal side and arranged at a distance from each other; a section C provided to connect the distal end of the second section; and The second sections (R2, L2) are aligned parallel to each other and straight, The direction in which the second section (R2, L2) extends forms an angle α of 35° to 120° with respect to the longitudinal direction in which the first section (R1, L1) extends, the second section (R2, L2) and the section C are arranged in one plane; Section C has a radius of 2.0 mm to 3.6 mm; A resectoscope (10) characterized in that the bending radius between the first section (R1, L1) and the second section (R2, L1) is 0.1 mm to 1 mm.

2. The resectoscope (10) according to claim 1, characterized in that the length of the second section (R2, L2) is between 0.7 mm and 1.7 mm.

3. The resectoscope (10) according to claim 1 or 2, characterized in that the conductive wire thickness of the first section (R1, L1) and / or the second section (R1, L1) is between 0.2 mm and 1.0 mm.

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