ELECTRODE INSTRUMENT FOR A RESECTOSCOPE, AND RESECTOSCOPE

Abstract

Radiofrequency instruments such as the resectoscope described here are used in medicine for treating body tissue and in particular for removing or manipulating this tissue. A particular disadvantage of the known instruments is that an irrigation liquid is disturbed by an electrode instrument in such a way that the resulting turbulence limits the view of the operator. The invention makes available an electrode instrument by which this problem is solved. This is achieved by the fact that two electrode casing tubes run from an electrode to the proximal end region of the electrode instrument and each have a respective electrical contact, namely an active contact and a return contact.

Claims

1. An electrode instrument for a resectoscope the electrode instrument having an electrode at a distal end and being able to be releasably coupled at a proximal end to a working element of the resectoscope via an electrical contact, wherein two electrode casing tubes run from the electrode to the proximal end and each have a respective electrical contact, namely an active contact and a return contact.

2. The electrode instrument as claimed in claim 1, wherein the electrical active contact is arranged electrically insulated inside an electrode casing tube, and the electrical return contact is formed by a casing of an electrode casing tube or is conductively connected to the casing of at least one electrode casing tube.

3. The electrode instrument as claimed in claim 1, wherein the active contact protrudes from the electrode casing tube for the electrical contacting at the proximal end.

4. The electrode instrument as claimed in claim 1, wherein at least distal and proximal portions of the electrode casing tubes run parallel to each other.

5. The electrode instrument as claimed in claim 1, wherein longitudinal axes of proximal and distal portions of the electrode casing tube lie in a common first plane, and longitudinal axes of proximal and distal portions of the electrode casing tube lie in a common second plane, wherein the first plane and the second plane are oriented parallel to each other and therefore the distance between the electrode casing tubes is identical along their entire length.

6. The electrode instrument as claimed in claim 1, wherein the proximal portions of the electrode casing tubes, are of a rectilinear configuration along a length of at least 24 mm, and/or the distal portions of the electrode casing tubes are of a rectilinear configuration along a length of at least 100 mm.

7. The electrode instrument as claimed in claim 1, wherein distal longitudinal axes of distal portions of the electrode casing tubes each have at least one offset in relation to proximal longitudinal axes of proximal portions of the electrode casing tubes.

8. The electrode instrument as claimed in claim 7, wherein the offset measures 2.5 mm to 3.5 mm.

9. The electrode instrument as claimed in claim 7, wherein the offset is S-shaped along a length of at most 30 mm.

10. The electrode instrument as claimed in claim 1, wherein the distance between the electrode casing tubes in the proximal region measures 5.4 mm to 5.8 mm, and/or the distance between the electrode casing tubes in the distal region measures 5.4 mm to 5.8 mm.

11. The electrode instrument as claimed in one of the claim 1, wherein the diameter of the electrode casing tubes measures 1 mm to 1.4 mm, wherein a cross section of the electrode casing tubes is circular or ring-like at least in some regions, along the entire length of the electrode casing tubes.

12. The electrode instrument as claimed in claim 1, wherein all the components of the electrode, in the proximal region are located within an extended, enveloping cylinder face of the casing tubes and do not protrude radially beyond same.

13. The electrode instrument as claimed in claim 1, wherein the electrode casing tubes are connected via at least one guide element, in the distal portion, via a first guide element in the distal portion and a second guide element in the proximal portion.

14. A resectoscope having an electrode instrument as claimed in claim 1.

Description

[0026] A preferred illustrative embodiment of an electrode instrument is described in more detail below with reference to the drawing, in which:

[0027] FIG. 1 shows a schematic view of a resectoscope,

[0028] FIG. 2 shows a schematic, perspective view of an electrode instrument,

[0029] FIG. 3 shows a view of the electrode instrument according to FIG. 2,

[0030] FIG. 4 shows a side view of the electrode instrument according to FIG. 2, and

[0031] FIG. 5 shows a view of a distal end of the electrode instrument according to FIG. 2.

[0032] FIG. 1 shows a possible illustrative embodiment of a resectoscope 10. In this resectoscope 10, an outer shaft 11, only symbolized here by dashed lines, is pushed over an inner shaft 12. The inner shaft 12 serves to receive and/or guide an optical unit 13, which extends from a distal end 14 to a proximal end 15 of the resectoscope 10. At the proximal end 15, an eyepiece 16 is available to allow a user to observe, through the optical unit 13, the region in which surgery is to be performed in front of the distal end 14.

[0033] An essential component of the resectoscope 10 is the working element 17. his working element 17 has a first gripping means 18, among other things, and is connected by a spring element 19 to a second gripping means 20 and to an optical plate 21.

[0034] Moreover, an electrode instrument 22 extends along the inner shaft 12 from the distal end 14 of the resectoscope 10 as far as the working element 17. At the distal end 14, the electrode instrument 22 has an electrode 23. Electrical energy is able to be applied to this electrode 23 by means of an RF generator (not shown) and serves to manipulate tissue.

[0035] The electrode instrument 22 is latched with a proximal end 24 in the working element 17. In this way, on the one hand, the electrode instrument 22 can be easily uncoupled from the working element 17 or coupled to the working element 17 and, on the other hand, can move together with the working element 17 along the longitudinal axis of the resectoscope 10 in the distal or proximal direction.

[0036] According to the invention, the electrode instrument 22 shown in FIG. 2 has two electrode casing tubes 26, 27. These electrode casing tubes 26, 27 are substantially rectilinear. The electrode casing tubes 26, 27 run parallel to each other along their entire length, i.e. from the distal end 14 to the proximal end 24. The distance between the electrode casing tubes 26, 27 measures between 5.4 mm and 5.8 mm, preferably 5.6 mm. At the distal ends, the two electrode casing tubes 26, 27 are mechanically connected to each other by the electrode 23 and electrically insulated from each other by the insulator 31. When an RF voltage is applied to the electrode instrument 22, a plasma forms around the electrode 23, designed here as a cutting loop. The electrical contacting of the electrode instrument 22 takes place via the two proximal ends of the electrode casing tubes 26, 27. While an active contact 28 insulated in the interior of the electrode casing tube 26 runs from the proximal end 24 to the electrode 23, an outer casing of the electrode casing tube 27 forms a return contact 29. As has already been described, these two contacts 28, 29 are plugged into the working element 17 and electrically connected by corresponding lines to the RF generator (not shown here).

[0037] The electrode casing tubes 26, 27 deviate from their rectilinear shape to the extent that proximal portions 32 each have an offset 30 with respect to distal portions 33. As a result of this offset 30, longitudinal axes of the proximal portions 32 and of the distal portions 33 of the individual electrode casing tubes 26, 27 are displaced parallel to each other, wherein the proximal portion 32 and the distal portion 33 of the electrode casing tube 26 lie in a first plane, which is oriented parallel to a second plane formed by the proximal portion 32 and the distal portion 33 of the electrode casing tube 27. The offset 30 between the displaced longitudinal axes can measure 2.5 mm to 3.5 mm, others 2.7 mm to 3.1 mm, preferably 2.9 mm. This offset 30 can be step-like or also S-shaped.

[0038] In the illustrative embodiment of the electrode instrument 22 shown in FIGS. 2-4, provision is made that the distal rectilinear portion 33 of the electrode casing tubes 26, 27 has at least a length of 100 mm, preferably of 200 mm. By virtue of this design at least of the distal portion 33 of the electrode casing tubes 26, 27, there is a particularly advantageous laminar flow of the irrigation liquid in the shaft 11. The rectilinear proximal portion 32 of the electrode casing tubes 26, 27 preferably has a length of 24 mm, preferably 40 mm. This dimensioning allows the contacts 28, 29 to be particularly easily and safely handled and coupled to the working element 17. For additional mechanical stability, the two electrode casing tubes 26, 27 can be coupled to each other via guide elements 25, as is shown in FIGS. 2 and 3. These guide elements 25 serve for mechanically stabilizing the electrode casing tubes 26, 27 relative to each other, but especially also for guiding the electrode instrument 22 on the inner shaft 12. During use of the resectoscope 10, the guide elements 25 lie on an outer jacket surface of the inner shaft 12 and slide with corresponding movement along the shaft axis. It can be seen from FIG. 5 that the cross section of the guide elements 25 is in the shape of a segment of a circle and can thus particularly advantageously conform to the outer shape of the inner shaft 12. It can also be seen from FIG. 5 that the guide elements 25 are fastened with their edge regions to the electrode casing tubes 26, 27, or these edge regions extend at least partially around the electrode casing tubes 26, 27. These guide elements 25 can be produced either from a metallic material or alternatively from a plastic or composite material. On account of the positioning of the guide elements 25 above the inner shaft 12, the irrigation liquid flowing through the shaft 11 remains unaffected by these plates 25.

[0039] In order to optimally utilize the limited interior space of the shaft 11, the diameter of the electrode casing tubes 26, 27 measures 1.0 mm to 1.4 mm, preferably 1.2 mm.

[0040] In addition to the resectoscope 10 shown here as an example, it is also conceivable for the electrode instrument 22 according to the invention to be connected to a resectoscope of a different configuration.

TABLE-US-00001 List of reference signs 10 resectoscope 11 outer shaft 12 inner shaft 13 optical unit 14 distal end of resectoscope 15 proximal end of resectoscope 16 eyepiece 17 working element 18 gripping means 19 spring element 20 gripping means 21 optical plate 22 electrode instrument 23 electrode 24 proximal end of electrode instrument 25 guide element 26 electrode casing tube 27 electrode casing tube 28 active contact 29 return contact 30 offset 31 insulator 32 proximal portion 33 distal portion