RADIOFREQUENCY ELECTRODE FOR USE IN A SURGICAL HANDHELD DEVICE, ELECTRODE INSTRUMENT AND RESECTOSCOPE

Abstract

A radiofrequency electrode for handheld devices are used predominantly in urology for electrosurgical work in the bladder, the prostate, and the urethra. A large active area of the electrode is known to be advantageous. However, the size of the area is restricted by the available space. Moreover, greater energy is required for igniting the plasma for large electrodes. However, an elevated energy level is disadvantageous in terms of the heat influx into the rinsing liquid and this may be disadvantageous for the surrounding tissue. The invention develops a radiofrequency electrode, an electrode instrument and a resectoscope, in which a plasma can be better localized at the electrode and the energy for igniting the plasma is reduced at the same time. This is achieved by virtue of a radiofrequency electrode for use in a surgical handheld device having the shape of a toroid.

Claims

1. A radiofrequency electrode for use in a surgical handheld device, more particularly in a resectoscope, wherein the radiofrequency electrode is able to be supplied with electric power by way of at least one electrical conductor, wherein the radiofrequency electrode has the shape of a toroid.

2. The radiofrequency electrode as claimed in claim 1, wherein the toroidal electrode for generating a plasma comprises an electrical conductor, by means of which electrical conductor the electrode is able to be coupled to a radiofrequency generator.

3. The radiofrequency electrode as claimed in claim 1, wherein the toroidal electrode for generating a plasma comprises two electrical conductors, said electrical conductors each contacting an electrical pole of the electrode and being able to be coupled to a radiofrequency generator, wherein the electrical poles of the electrode are electrically insulated from one another by way of an insulator element.

4. The radiofrequency electrode as claimed in claim 1, wherein at least one electrical pole, more particularly a neutral electrode and/or a return electrode, of the electrode is formed by a support arm or a fork tube of the electrode.

5. The radiofrequency electrode as claimed in claim 1, wherein the electrode is fastened, preferably detachably fastened, to the handheld device, in particular to an electrode instrument, via the at least one electrical conductor and/or at least on a holding element.

6. The radiofrequency electrode as claimed in claim 1, wherein the at least one electrical conductor, preferably the two electrical conductors, contact the toroid at an inner side.

7. The radiofrequency electrode as claimed in claim 1, wherein a cross section parallel to a radial axis of the toroid has an embodiment that is elliptical, oval, circular, triangular, quadrilateral, preferably square, trapezoidal, polygonal or the like.

8. The radiofrequency electrode as claimed in claim 1, wherein an outer circumference of the toroid has an embodiment that is elliptical, oval or circular.

9. The radiofrequency electrode as claimed in claim 1, wherein a ring-like protrusion, preferably an edge, is formed around an external circumference of the toroid surface.

10. The radiofrequency electrode as claimed in claim 3, wherein a first electrical conductor is assigned to a lower section of the toroid and this section forms a first electrical pole and a second electrical conductor is assigned to an upper section of the toroid 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.

11. The radiofrequency electrode as claimed in claim 1, wherein an outer diameter, in particular mean outer diameter, of the toroid 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.

12. The radiofrequency electrode as claimed in claim 1, wherein the toroid substantially consists of stainless steel, titanium, platinum iridium or platinum tungsten and an electrical insulator consists of a ceramic or a plastic.

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

14. A resectoscope comprising an electrode instrument as claimed in claim 13.

Description

[0021] Preferred exemplary embodiments of the invention will be described in more detail below with reference to the drawing. In this drawing:

[0022] FIG. 1 shows a schematic illustration of a surgical handheld device, more particularly a resectoscope,

[0023] FIG. 2 shows an exemplary embodiment of a radiofrequency electrode,

[0024] FIG. 3 shows a further exemplary embodiment of a radiofrequency electrode,

[0025] FIG. 4 shows a further exemplary embodiment of a radiofrequency electrode,

[0026] FIG. 5 shows a further exemplary embodiment of a radiofrequency electrode,

[0027] FIG. 6 shows a further exemplary embodiment of a radiofrequency electrode, and

[0028] FIG. 7 shows a further exemplary embodiment of a radiofrequency electrode.

[0029] FIG. 1 illustrates a resectoscope 10 as an example of a surgical handheld device. This resectoscope 10 substantially consists of a carrier 11, a grip unit 12 and a shaft 13, which should be guided into an appropriate body orifice for the purposes of treating a patient. In the exemplary embodiment illustrated here, the shaft 13 is composed of an outer shaft tube 14, an optical unit 15 and an electrode instrument 16. The optical unit 15 consists of a long tube in which lenses or optical fibers can be arranged in order to observe the region of the treatment at the distal end of the shaft 13 through an eyepiece 17 arranged proximally on the shaft 13. Reference is made to the known prior art in respect of a more detailed description of a resectoscope.

[0030] The electrode instrument 16 is substantially composed of a radiofrequency electrode 18 and at least one electrical conductor 19. Firstly, the at least one electrical conductor 19 supplies the radiofrequency electrode 18 with a radiofrequency voltage and, secondly, the conductor 19 and optionally a further element serve as a holder of the electrode 18 on the electrode instrument 16. The electrical conductor 19 runs from the distal end of the resectoscope 10 through the shaft 14 and is connected by further lines to a radiofrequency generator (not illustrated) for generating the radiofrequency electromagnetic energy. The two conductors 19, 20 are able to be guided through the two support arms 29, 30 or through the fork tubes of the electrode instrument 16 (FIG. 2).

[0031] Tissue, for example, can be manipulated by means of the radiofrequency electrode 18. To this end, the radiofrequency electrode 18 can be embodied either as a monopolar electrode or as a bipolar electrode. In the case of a bipolar electrode, the latter is connected to two electrical conductors 19, 20. In the exemplary embodiment of a monopolar electrode, the electrode 18 is only connected to one electrical conductor 19. A further neutral electrode is attached to the patient or is integrated in the resectoscope (shaft, carrier, optical unit; if all components are at one electrical potential, this leads to a lower current density on account of the large area). A plasma by means of which tissue is manipulated by way of an appropriate movement of the electrode instrument 16 is generated at the electrode 18 by supplying the radiofrequency electrode 18 with electric power.

[0032] The radiofrequency electrode 18 as per the present invention is embodied as a toroid 21. In FIG. 2, a toroid 21 with a circular cross section is illustrated in exemplary fashion. This toroid 21 is electrically connected to the power source by way of two electrical conductors 19, 20 of the electrode instrument 16. Alternatively, it is conceivable for one of the conductors 19, 20 to be embodied as a holding element.

[0033] The toroid 21 or the radiofrequency electrode 18 has a lower region 22 and an upper region 23. These regions 22, 23 can have different sizes. In the exemplary embodiment illustrated 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. Equally, it is conceivable for the upper region 23 to be affixed to by the further holder. An insulator for insulating the two electric poles from one another is provided between the electrically conductive regions 22 and 23 in the case of a bipolar electrode. A particularly large plasma in terms of area, which allows much tissue to be ablated within a short period of time, can be generated at the lower region 22 of the electrode 18 by this special embodiment of the radiofrequency electrode 18. The active surface of the electrode 18 can be kept small by the toroidal shape of the radiofrequency electrode 18, and so a small amount of heat or little electric energy is required for igniting the plasma. Moreover, this shape is particularly advantageous for fast ignition of the plasma.

[0034] The ratio between an outer circumference of the “donut-shaped” radiofrequency electrode 18 and an inner circumference can assume any desired values. Depending on the type of treatment or the use, it is possible to use toroids 21 with different dimensions. FIGS. 3 to 7 illustrate different toroidal structures. Thus, FIG. 3 shows an example of a radiofrequency electrode 18, in which a cross section of a toroid 24 has a rectangular or square embodiment. In the toroid 25 illustrated in FIG. 4, the cross section has a trapezoidal embodiment. The exemplary embodiment in FIG. 5 shows a toroid 26 with a triangular cross section. The exemplary embodiment of a toroid 27 as per FIG. 6 likewise exhibits a triangular cross section. However, the triangle is tilted in such a way in this exemplary embodiment that one tip points to the outside. FIG. 7 illustrates a further exemplary embodiment of a toroid 28. As a result of the different shapes, different plasmas form at the radiofrequency electrode 18 on account of the different electric field strengths. Thus, a particularly advantageously shaped electrode 18 can be selected according to requirements. Here, explicit reference is made to the fact that the selection of toroidal shapes illustrated here is not exhaustive. Rather, it is conceivable for the toroids to be able to adopt virtually any shape.

[0035] One exemplary embodiment of the invention, not illustrated, can provide for an edge or ring-like fringe to be arranged at an outer side of the toroid 21. This edge promotes the formation of a plasma, as a result of which, firstly, the ignition energy is able to be reduced and, secondly, the ignition time can be shortened.

[0036] The radiofrequency electrode 18 according to the invention can be connectable to the resectoscope 10 in plug-like fashion together with the electrode instrument 16. Equally, it is conceivable for the electrode 18 to be connectable to the electrode instrument 16 in plug-like fashion. This is particularly advantageous for maintenance and cleaning purposes in particular.

[0037] Express reference is made to the fact that the use of the radiofrequency electrode 18 is not restricted to a urological application. Rather, it is also conceivable that this electrode 18 can find use in orthopedic or other surgical or medical uses.