Electrode for electrosurgical handheld instrument

Abstract

The invention relates to an electrode for an electrosurgical handheld instrument. The invention relates to an electrode for an electrosurgical hand-held instrument, by means of which an electrosurgical treatment can be carried out in a reliable and safe manner even if a metal element is present in the region to be treated. To this end, it is provided that the electrode (16) for the electrosurgical hand-held instrument consists of an electrically conductive wire (18), both ends of which can be connected to an electrode support (14) of the electrosurgical hand-held instrument. In this case, the electrode (16) has a first section (R) and a second section (L), which adjoin both ends of the electrode (16) and may be aligned parallel to each other and straight. The first section (R) and the second section (L) adjoin each other by a third section (C), which connects the first section (R) and the second section (L) to each other. According to the invention, the conductor wire (18) has a cross-sectional diameter (25) of 0.5 mm to 1.0 mm.

Description

Technical Field

[0001] The present invention relates to an electrode for an electrosurgical hand instrument. Background Art

[0002] Electrosurgical handheld devices of the type described, in particular resectoscopes, are primarily used for electrosurgical work in urology. In this context, these devices are usually used to cut and vaporize tissue, for example in the lower urethra. To this end, the handheld device, in particular a resectoscope, can comprise a longitudinally displaceable electrode support which can be advanced from the distal end of the instrument shaft of the handheld device with the distal working end after the device has been inserted into the body to be treated. An electrosurgical electrode is arranged on the electrode support at its distal end. Depending on the design of the instrument, this electrode can be in the form of a ring, for example, and is pulled or pushed through the tissue to manipulate it.

[0003] The known electrodes are formed of a wire. For example, for an annular electrode, the known wire is formed into a ring and the two free ends are connected to the electrode support. When a high frequency alternating voltage is applied, a plasma is ignited at the electrode, so that a plasma is formed on the wire, interacting with the liquid surrounding the electrode. The plasma ignites preferentially at locations of the electrode with a small radius of curvature, because the electric field strength is greatest there.

[0004] In high-frequency surgery, it has been proven that the situation in which metal implants or other elements made of conductive materials are inserted in the tissue area of ​​the patient to be treated during the previous treatment is problematic. When the high-frequency potential is applied to the electrode, discharges or sparks may occur between the electrode and the metal element. This leads to uncontrolled and even undesirable manipulation of human tissue. The resulting patient trauma is unforeseeable and should therefore be avoided. Secondly, due to this discharge, the degree of corrosion to which the electrode is subjected is greatly increased, thereby increasing the risk of fracture. In addition, the electrode may be directly melted by the very high current occurring locally in a short time. The two fracture points or two free ends of the electrode may cause serious harm to the patient. In addition, there is a risk of arc formation between the two fracture ends, which in turn leads to uncontrolled manipulation of the tissue.

[0005] The invention is therefore based on the problem of producing an electrode which enables electrosurgical treatment to be carried out in a reliable and safe manner even in the presence of metallic elements in the area to be treated. Summary of the invention

[0006] Therefore, an electrode for an electrosurgical handheld instrument, in particular an electrode for an electroresectoscope, is provided, which consists of a conductive wire, wherein the two ends of the conductive wire can be connected to the electrode support of the handheld instrument. In this case, the conductive wire has a first section and a second section, which are adjacent to the two ends of the electrode support and can be parallel and straight to each other. The first section and the second section are adjacent to each other by a third section, which connects the first section and the second section to each other. According to the present invention, the cross-sectional diameter of the conductive wire is specified to be 0.5mm to 1.0mm. As a result of this significantly increased cross-sectional diameter of the conductive wire, the electrode has sufficient strength even in the event of unpredictable sparks and will not break at least during the activation time. Due to the greater mass compared to known electrodes, the material loss caused by corrosion is less severe. A particularly preferred embodiment of the present invention can provide that the conductive wire has a cross-sectional diameter of 0.8mm.

[0007] Preferably, provision can be made for the first section and the second section of the conductive line to be arranged parallel to one another. However, it is also conceivable that the first section and the second section enclose an angle and / or have a radius. Similarly, it is conceivable that the third section is formed as an arc or a ring. Depending on the type of treatment and the embodiment of the electrode, it can have almost any shape. For example, it is also conceivable that the first section, the second section and the third section consist of further subsections that enclose an angle or have a radius relative to one another. Due to this flexibility in the shape of the electrode, it is conceivable to use a specifically formed electrode for each application.

[0008] Another particularly advantageous embodiment provides that the conductive wire is made of a conductive material with a very high melting point, such as tungsten, molybdenum or tantalum. These materials have been shown to be particularly suitable for the above-mentioned applications. The melting point should be at least 2000° C., preferably greater than 3000° C., in particular greater than 3400° C.

[0009] Furthermore, it is provided that according to the invention the conductive wire has a circular or annular cross section. This choice of electrode shape allows particularly cost-effective production. Ultimately, the conductive wire of the above-mentioned material must be bent into the correct shape to produce the electrode. On the one hand, this production can be carried out easily and, importantly, it is reproducible, thereby ensuring the desired cost-effective production, especially for so-called disposable tools.

[0010] Preferably, it is provided that the first section, the second section and the third section are located in one plane, or the first section, the second section and the third section are located in two different planes. Another embodiment may provide that the first section, the second section and the third section are respectively arranged at right angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The preferred embodiments of the present invention are described in more detail below with reference to the accompanying drawings.

[0012] Figure 1 is a schematic diagram of a handheld surgical instrument, specifically a resectoscope,

[0013] Figure 2 is a side view of the electrode, and

[0014] Figure 3 is a front view of the electrode.

[0015] List of reference numerals:

[0016] 10 Resectoscope

[0017] 11 Resectoscope axis

[0018] 12 External axis

[0019] 13 Inner shaft

[0020] 14 Electrode support

[0021] 15 Optics

[0022] 16 Electrodes

[0023] 17 Guide element

[0024] 18 Conductive thread

[0025] 19 Handle

[0026] 20 Bracket

[0027] 21 First handle

[0028] 22 Second handle part

[0029] 23 Spring Bridge

[0030] 24 Eyepiece

[0031] 25 Cross section

[0032] R first segment

[0033] L Second segment

[0034] C Section 3

[0035] α Angle DETAILED DESCRIPTION

[0036] Figure 1A schematic side cross-sectional view of a resectoscope 10 is shown. The resectoscope 10 has a resectoscope shaft 11, which includes an outer shaft 12 or sheath. A tubular inner shaft 13 extends within the outer shaft 12. An electrode support 14 and an indicated optical device 15 are shown within the inner shaft 13. In addition, other elements not shown here can be provided within the resectoscope 10, such as a separate irrigation tube or the like.

[0037] The electrode support 14 has at a distal end an electrosurgical tool or electrode 16. The electrode 16 shown here is shown as being annular in shape, but may have other shapes.

[0038] By actuating the handle 19, the electrode support 14 can be forced to move axially in the distal direction and in the proximal direction. In this way, it can be pushed beyond the distal ends of the inner shaft 13 and the outer shaft 12. This allows the surgeon to manipulate the tissue further away from the end of the resectoscope. In addition, for this purpose, the inner shaft 13 and / or the electrode support 14 can be mounted in a rotatable manner around their longitudinal axis. In order to manipulate the tissue, a high-frequency current is applied to the electrode 16.

[0039] Figure 1 The resectoscope 10 shown has a passive transmission device, wherein the bracket 20 is displaced in the distal direction against the distal first handle portion 21 by the relative movement of the first handle portion 21 and the second handle portion 22 arranged proximally on the resectoscope shaft 11 against the spring force applied by the spring bridge 23. When the bracket 20 is displaced in the distal direction against the first handle portion 21, the electrode support 14 is displaced in the distal direction in a manner not shown. When the load on the first handle portion 21 and the second handle portion 22 is released, the spring force generated by the spring bridge 23 forces the bracket 20 to return to its initial position, thereby pulling the electrode support 14 in the proximal direction. When the bracket 20 moves back, electrosurgery can be performed using the electrode 16 without the operator's manual force (i.e., passively).

[0040] In order to carry out targeted treatment with the aid of the electrodes 16, the optics 15 are positioned so that the surgeon has an optimal view of the surgical area. To this end, the resectoscope 10 has an eyepiece 24 at the proximal end, which is connected to the optics 15. Alternatively, it is also conceivable that the camera is arranged on the resectoscope 10 instead of on the eyepiece 24.

[0041] Figure 2 and Figure 3 An example embodiment of an electrode 16 according to the invention is shown. The electrode 16 has a first section R and a second section L, wherein the first section R and the second section L are obviously of equal length and are oriented parallel to each other. The first section R and the second section L are connected to the distal end of an electrode support tube.

[0042] The third section C is located between the first section R and the second section L. In the exemplary embodiment of the electrode 16 shown here, the third section C or the plane in which the third section C lies is rotated by an angle α=90° relative to the plane defined by the first section R and the second section L. Similarly, it is conceivable that the angle α takes different values.

[0043] The length of the first section R and the second section L can be a few millimeters up to 2 cm, and the distance between the first section R and the second section L is a few millimeters. According to the invention described herein, the cross-sectional diameter 25 of the electrode 16 at the first section R, the second section L and the third section C is 0.5 mm to 1.0 mm, preferably 0.7 mm to 0.9 mm, in particular 0.8 mm. It has been shown that such a size of the cross-sectional diameter 25 is very advantageous, in particular when other metal objects are located near the area to be treated.

[0044] In addition to the annular shape of the electrode 16 shown here as an example, it is also conceivable that the third segment C has other shapes, such as a ring with a smaller or larger radius of curvature. Similarly, it is conceivable that the third segment C includes a plurality of subsegments, each subsegment enclosing an angle.

Claims

1. An electrode (16) for an electrosurgical hand instrument, in particular an electrode for an electroresectoscope (10), the electrode being composed of a conductive wire (18), wherein both ends of the conductive wire (18) are connectable to an electrode support (14) of the electrosurgical hand instrument, characterized in that: The conductive wire (18) has a cross-sectional diameter (25) of 0.5 mm to 1.0 mm.

2. The electrode (16) for an electrosurgical hand instrument according to claim 1, characterized in that The electrode (16) comprises a first section (R), a second section (L) and a third section (C), wherein the first section (R) and the second section (L) have two first ends adjacent to the electrode support (14) and two second ends respectively connected to the third section (C).

3. The electrode (16) for an electrosurgical hand instrument according to claim 1 or 2, characterized in that: The first section (R) and the second section (L) of the conductive line (18) are arranged parallel to each other and are straight.

4. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The third section (C) is formed in an arc shape or a ring shape.

5. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The conductive wire (18) is made of a conductive material having a high melting point, such as tungsten, molybdenum or tantalum.

6. The electrode (16) for an electrosurgical hand instrument according to claim 5, characterized in that The melting point is at least 2000°C, preferably greater than 3000°C, in particular greater than 3400°C.

7. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The conductive wire (18) has a circular or annular cross section.

8. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The first segment (R), the second segment (L) and the third segment (C) are located in one plane, or the first segment (R), the second segment (L) and the third segment (C) are located in two different planes.

9. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The first section (R) and the second section (L) are arranged at right angles to the third section (C).

10. An electrode (16) for an electrosurgical hand instrument according to any one of the preceding claims, characterized in that The cross-sectional diameter (25) of the conductive wire (18) is 0.8 mm.

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