CN100544681C

CN100544681C - Electrosurgical unit

Info

Publication number: CN100544681C
Application number: CNB2005800213469A
Authority: CN
Inventors: 克劳斯·菲舍尔
Original assignee: Erbe Elecktromedizin GmbH
Current assignee: Erbe Elecktromedizin GmbH
Priority date: 2004-06-28
Filing date: 2005-05-25
Publication date: 2009-09-30
Anticipated expiration: 2025-05-25
Also published as: JP2008504084A; JP4652405B2; EP1778112B1; CN1976642A; US8623016B2; DE102004031141A1; WO2006000280A1; EP1778112A1; US20080045944A1

Abstract

The present invention discloses a kind of electrosurgical unit, and it has two branches that combine, and it can be driven in the mode of compression tool.This apparatus also is included in the electrod assembly of branches end, its be used for grasping tissue and be used for conduction condense electric current by tissue causing that it condenses, and be used for providing the current supply device of electric current that condense to electrod assembly from the H.F. generator.Arrange the device of at least one prevention short circuit and be designed to the mode that electrod assembly can not be in contact with one another.Develop this electrosurgical unit so that the distance between electrod assembly can be conditioned more reliably to mate required H.F. voltage.For this purpose, be used to prevent that the device of short circuit is designed in electrod assembly.

Description

Electrosurgical instrument

Technical Field

The present invention relates to an electrosurgical instrument.

Electrosurgical instruments have been used for some years in high frequency surgery for coagulating or cutting biological tissue. With coagulation, high frequency current is passed through the tissue being treated, causing changes in the protein due to coagulation and dehydration. Here, the tissue contracts in the form of vessel occlusion and blood flow stagnation. The cutting process requires high current density, the tissue is divided into two by the action of explosive evaporation of tissue fluid and complete tearing of the cell membrane.

The use of bipolar instruments is becoming increasingly important because of the lower current density required than monopolar instruments. It is particularly advantageous that the direction of the current between the electrode parts of the bipolar instrument can be calculated and does not continue any distance through the patient's body.

Bipolar instruments are key provided with two combined press parts, whereby a gripping means is provided at its proximal end for operating the press parts. At the distal end of the squeezing portion there is an electrode member for grasping tissue and conducting coagulation current through the tissue. The voltage generated by the HF generator, and the HF current supplied by it, are conducted via the current supply device to the electrode parts of the bipolar instrument. To prevent short circuits due to contact of the two electrode parts, the known instrument has means for preventing short circuits on the limbs, whereby the electrode parts are always spaced apart when the instrument is closed.

A problem of the known devices for preventing short-circuits is that they only indirectly define the spacing between the electrode parts, since they are separate from the electrode parts. Thus, for example, the aspect ratio of the branches needs to be taken into account to determine the appropriate spacing. This makes it considerably difficult to adjust the spacing and the required HF voltage.

It is therefore an object of the present invention to further develop an electrosurgical instrument of the type indicated at the outset such that it can adjust the spacing between the electrode parts to the desired HF voltage.

This object is achieved by the following electrosurgical instrument.

An electrosurgical instrument comprising

Two combined branches, which can be driven in the manner of a press tool,

an electrode member at the distal end of the branches for clamping tissue and for conducting a coagulation current through the tissue to cause coagulation thereof,

-current supply means for supplying a coagulation current from the HF generator to the electrode member and

at least one means for preventing short-circuits, which is arranged on the electrode parts and arranged and configured in such a way that the electrode parts cannot be contacted, and which comprises an insulation on at least one electrode part,

wherein at least one cutting portion for cutting with an electric arc is arranged on at least one electrode part,

and wherein the insulating part is disposed on and protrudes from the cutting part or the electrode part opposite to the cutting part in such a manner that the electrode part, the cutting part, and the insulating part are overlapped with each other in the direction in which the branches move, so that the electrode parts are spaced apart by the insulating part when the branches are brought together.

In particular, this object is achieved by an electrosurgical instrument consisting of two joined branches, which are driven in the manner of a pressing tool. The instrument further comprises an electrode member at the distal end of the limb for grasping tissue and for conducting a coagulating current through the tissue to cause coagulation thereof, and a current supply means for supplying the coagulating current from the HF generator to the electrode member. At least one means for preventing short-circuiting is arranged and configured in such a way that the electrodes cannot touch, whereby the means for preventing short-circuiting is configured on the electrode part.

The key point of the present invention is that the means for preventing short circuit is directly disposed at a position where it is necessary to have an effective interval between the electrode parts. At the same time, coagulation is not impeded because tissue can also be coagulated at the point of contact between the tissue and the device due to thermal conduction. To this extent, any spark discharge between the electrode members can be reliably avoided with the coagulation operation.

In a preferred embodiment, the device for preventing short circuits has a distance element as an insulation on at least one of the electrode parts. Therefore, even if they are in contact, a short circuit between the electrode parts can be prevented by the distance element.

In a further preferred embodiment, adjoining the insulation, at least one initial cutting section is arranged on at least one electrode part, in particular configured with a decreasing spacing from the opposite electrode with respect to the coagulation electrode, in such a way that an arc for cutting into tissue is generated from the initial cutting section with any increase in the coagulation current voltage. The cut-out is preferably arranged on the electrode part as a region tapering with respect to the electrode part and protruding from the electrode part. The electrode component then has a distinct condensation in addition to the cut-out. During the coagulation operation, the electrode parts forming the coagulation section and the cutting section can be operated as coagulation electrodes over their entire surface area, i.e. both the surface area of the coagulation section and the surface area of the cutting section, whereas the tapering cutting section alone can be used for the subsequent cutting operation.

The cut-out ensures that an arc is only generated here, but as a result of the spacing between the electrode parts being too large, destructive discharges to the opposite electrode cannot occur in the rest of the electrode parts. Thus the same instrument can be used for both coagulation and cutting, and the advantage of avoiding changing instruments with consequent uninterrupted operation can be achieved.

The distance elements may be configured as lines and dots. For example, the linear distance elements will then extend in the direction of the extension of the branches, be arranged concentrically over the entire electrode part and thus form an edge. Advantageously, in this way it is possible to form a stable arc and a uniform cut can be ensured. The punctiform distance elements are easy to produce, reliably prevent short circuits between the electrode parts and, as a result of the heat conduction, also ensure safe coagulation at the contact points between the tissue and the distance elements. Several punctiform distance elements arranged on the respective electrode parts, for example at the respective ends of the electrode parts, reliably prevent short circuits and do not affect neither coagulation nor cutting operation.

Preferably, the second cut portion is to be disposed on the electrode member facing the electrode member having the insulating portion. It is particularly advantageous if the insulation facing the second cut is arranged directly on the electrode part so that the electrode part has no distinct initial cut. In this embodiment, the insulation is preferably smaller than the opposing cut so that an arc can form around the peripheral region of the insulation towards the opposing cut. This makes it possible to achieve accurate cutting.

Alternatively, the cutting portions may be provided on both of the opposing electrode members. The arc formation and cutting propagation area is thus determined extremely accurately.

Preferably, the means for preventing short circuits has at least one insulating part which is formed within the electrode part. The distance elements provided as cut-outs are then arranged on the electrode parts facing the insulation. When the branches are brought together, the cut portions are arranged in such a way as to contact only the insulation. Advantageously, a precise cut is also provided here, since an arc is formed between the integrated part and the cutting part. The insulation in this embodiment is protected from shocks or similar mechanical stresses and is also critically protected from arcing.

In this embodiment, the insulating portion may be configured such that the electrode surface of the electrode component having the insulating portion is filled. This allows the electrode assembly to be cleaned easily and safely after treatment.

Alternatively, the insulating part can be arranged so that it sinks in the respective electrode part, whereby the electrode part has a recess. The cutting portion arranged on the counter electrode part may thus be at least partially embedded in the recess, so that an arc can form towards the cutting portion within the recess during a cutting operation. The surrounding tissue is thus protected from burning, while at the same time the cutting line can be accurately determined.

In a preferred embodiment, the insulation portions may be arranged in a symmetrical manner with respect to the initial cut and/or the second cut on the respective electrode part. The symmetrical arrangement of the co-operating portions ensures that the arc is formed evenly over the peripheral area of the distance element, which contributes to an even cut.

One possible embodiment provides a distance element configured in such a way that a mechanical cutting can be performed. Preferably, the distance element will then have a cutting edge that causes a mechanical cutting of itself. With proper application by the surgeon, the tissue may then be completely incised after the coagulation step and no instrument changes are necessary. This allows a particularly soft treatment of the tissue to be achieved.

In a preferred embodiment, on at least one electrode part, the cutting portion is configured as an edge having a substantially triangular cross-section. The triangular cross-section allows a continuous transition from one large surface area of the electrode part to its knife-edge taper. The smoothing is particularly suitable for using the entire electrode assembly as a coagulation electrode where there is sufficient tissue thickness, since the entire surface area and the tissue can be in contact with each other.

Advantageously, the cut-out on at least one of the electrode parts is configured as a knife edge having a substantially circular or circular cross-section. At an transition between the distinct condensation portion and the cutting portion, it is preferred to configure the cutting portion in a truncated manner to ensure that the cutting portion is firmly fixed to the respective electrode part. In this embodiment, a relatively large electrode surface is available for coagulation, however a cutting portion configured as a knife edge can hardly be used where there is sufficient tissue thickness. On the other hand, at advanced stages of operation, and when the opposing electrode components of the electrosurgical instrument are sufficiently close, the knife-edge configuration of the cutting portion allows the current density to be increased in a manner that allows for a cutting operation.

Preferably, the insulation is constructed from a material that is resistant to arc erosion. Thus, a reliable resistance to arc wear is provided.

In a preferred embodiment, the insulating part consists of a ceramic material. Advantageously, the ceramic is also highly resistant to high corrosion resistance and to arc wear and mechanical stresses.

In the following, the invention is described from examples of embodiments, which are described in more detail from the illustrations. They describe

FIG. 1a schematically depicts the electrode arrangement during the coagulation phase in a first embodiment;

FIG. 1b the electrode arrangement according to FIG. 1a at the end of the coagulation phase;

FIG. 1c the electrode arrangement according to FIG. 1a during a cutting phase;

FIG. 2 schematically depicts an electrode arrangement in a second embodiment;

FIG. 3 schematically depicts an electrode arrangement in a third embodiment;

FIG. 4 schematically depicts an electrode arrangement in a fourth embodiment;

FIG. 5 schematically depicts an electrode arrangement in a fifth embodiment;

fig. 6 schematically depicts an electrode arrangement in a sixth embodiment;

fig. 7 schematically depicts an electrosurgical instrument having an electrode arrangement according to the present invention.

In the following description, the same reference numerals are used for the same and similar working components.

Fig. 1a depicts a front view of a cross-section of an electrode arrangement according to the invention during a coagulation phase in a first embodiment. Shown here are two opposing

electrode parts

18, 19, one of which 18 has a cut 18a and an insulation 21 as distance elements. In this embodiment the distance elements form means 20 for preventing short-circuits. The tissue 30 to be treated is clamped between the electrodes.

The insulation 21 prevents an undesired short-circuit between the

electrode parts

18, 19 when the

branches

11, 12 are brought together, and it can be configured in a line-shaped and a point-shaped manner. For example, the linear distance elements will then extend in the direction of the extension of the branches, concentrically arranged over the entire electrode part and thus form edges. Advantageously, it is thus possible to form a stable arc and to ensure a smooth cut. The punctiform distance elements are easy to produce, reliably prevent short circuits between the electrode parts, and also ensure safe coagulation at the contact points between the tissue and the distance elements as a result of the heat conduction. Several punctiform distance elements arranged at the respective electrode parts, for example at the respective ends of the electrode parts, reliably prevent short circuits and do not affect neither coagulation nor cutting operation. And the cut portion 18a is configured in a linear shape in any case.

In addition to preventing short circuits, portion 21 defines the thickness of tissue 30 that remains after the coagulation phase because it prevents premature arcing due to any preset coagulation voltage due to too small a spacing between the

electrode members

18, 19.

Fig. 1b depicts the electrode arrangement according to fig. 1a, although the end of coagulation is shown here. The coagulation current flows over the entire surface of the

electrode parts

18, 18a, 19 according to fig. 1a and 1b, the tissue 30 placed therebetween being coagulated. As a result of the heat conduction, the tissue 30 under the insulating part 21 is coagulated.

Fig. 1c depicts the arrangement of the electrodes described above during the cutting stage. At the end of the coagulation phase, the HF voltage required for the electrosurgical treatment is slightly increased, with the result that an arc 23 is formed between the cutting section 18a and the counter electrode part 19, which now cuts the already coagulated tissue 30.

The cut portion 18a is preferentially arranged on the electrode part 18 as a region tapered with respect to the electrode part 18 and protrudes therefrom. The electrode member 18 will then consist of distinct coagulated portions, except for the cut portion 18 a. During the coagulation operation, the electrode member 18 forming the coagulation section and the cutting section 18a can be operated as a coagulation electrode over its entire surface area, i.e. over the surface area of the coagulation section and over the surface area of the cutting section 18a, while the tapering cutting section 18a alone can be used for the subsequent cutting operation.

The height of the insulating portion 21, and thus the spacing from the cutting portion 18a and the opposing electrode member 19, and the HF voltage required for cutting are mutually adjusted. Thus avoiding the formation of an arc 23 outside the cut 18a, i.e. in the remaining area of the electrode member 18.

Because the same instrument can be used for both coagulation and cutting as with the described electrode arrangement, the benefit of changing instruments to provide uninterrupted operation can be avoided.

In fig. 2a, a front view of a section of the electrode arrangement in a second embodiment is shown. For better illustration, the tissue clamped between the electrode parts during treatment is not shown in this embodiment. In addition, the same applies to fig. 3 to 6. The arrangement differs from that shown in fig. 1a-1c in that the cutting portion 18a is configured as an edge having a triangular cross-section. Because of the continuous transition from a large surface area of the electrode member 18 to its knife-edge taper, this solution is particularly suitable for using the entire electrode member 18 as a coagulation electrode where there is sufficient tissue thickness, since the entire surface area and the tissue can be in contact with each other. With a suitable HF voltage, an arc 23 is formed between the cutting section 18a and the opposing electrode part 19.

The insulation 21 has in this case a tapering shape, which facilitates mechanical cutting if necessary, that is to say the distance elements have a sharp cutting edge 22. With proper application by the surgeon, the tissue may then be completely incised after the coagulation step and no instrument changes are necessary. This makes it possible to perform particularly gentle treatment of the tissue without using an electric arc.

Fig. 3 depicts a front view of a cross section of an electrode arrangement in a third embodiment. Here, the cut portion 18a is disposed on the electrode member 18 and the cut portion 19a is disposed on the electrode member 19. The insulation 21 is arranged directly below the cut-outs 18a and is symmetrical with respect to the cut-

outs

18a, 19 a. The symmetrical arrangement of the cooperating

portions

18a, 21, 19a ensures that the arc 23 is generated uniformly in the peripheral region of the insulating portion 21, facilitating uniform cutting. The insulating portion 21, which functions as a distance element, is smaller than the

cut portions

18a, 19a so as not to hinder the formation of the arc 23. Since the

narrow cutting portions

18a, 19a are accommodated in the

electrode members

18, 19, the cutting progress can be determined extremely accurately.

A very simple embodiment of an electrode arrangement is depicted in fig. 4. Here, the electrode member 19 has only the cut portion 19a, and only the insulating portion 21 is disposed on the electrode member 18 facing the electrode member 19. Since the arc 23 is formed in the direction of the cutting section 19a, this embodiment allows an accurate cutting line to be determined in a particularly easy manner.

Fig. 5 depicts a front view of a cross-section of the electrode arrangement when the electrode part 18 of the insulation 21 is arranged within the electrode part 18, wherein the insulation 21 is flush with the electrode surface 18 b. The second cut 19a on the opposite electrode part 19 is provided as a distance element. The insulating portion 21 and the cutting portion 19a operate as a means 20 for preventing short circuit in this embodiment. Advantageously, here also an accurate cut is provided, since an arc 23 is formed between the integrated portion 21 and the cut portion 19 a. This embodiment protects the insulation 21 from shocks or similar mechanical stresses and also from arcing.

Fig. 6 depicts a configuration of an electrode arrangement similar to that shown in fig. 5. However, the insulating portions 21 arranged here sink into the respective electrode members 18, so that the concave portions 18c are formed on the electrode members 18. The cut 19a arranged on the counter electrode part 19 may at least partly descend into the recess 18c so that an arc 23 can be formed in the recess 18c towards the cut 19a during the cutting operation. The surrounding tissue is thus protected from burning, while at the same time an accurate cutting line can be determined.

Also in this embodiment, the cutting portion 19a may be configured with a sharp cutting edge, which allows mechanical cutting of tissue.

Fig. 7 depicts a fully illustrated electrosurgical instrument 10 having an electrode arrangement in accordance with the present invention. In the example,

reference numerals

11 and 12 denote two branches of the electrosurgical instrument 10. The two

branches

11, 12 have ends 13, 14 to which

electrode parts

18, 19 are mounted, wherein the

electrode parts

18, 19 face each other. For example, by means of the

electrode members

18, 19, it is possible to grasp a vessel and coagulate or cut the vessel by supplying a high-frequency current. Furthermore, a clamping portion 11a, 12a is provided, which is connected to the

proximal end

15, 16 of each

branch

11, 12. The proximal ends 15, 16 of the

pressing portions

11, 12 end in a connecting element 17a of a current supply device 17. The current supply 17 connects the electrosurgical instrument 10 to an HF generator (not shown), which generates an HF voltage so that an HF current can be supplied to the

electrode components

18, 19 by, for example, electrical leads (not shown) through the instrument 10.

The blade-shaped cutting portion 18a is disposed on the electrode member 18. Which is provided with two insulation portions 21, 21' as two punctiform distance elements. The distance elements arranged on the respective ends or cutting portions 18a of the electrode parts 18 reliably prevent short circuits and do not affect neither coagulation nor cutting operation.

In order to obtain a high resistance of the insulating part against electric arcs, the part is preferably made of a material resistant to arc corrosion. In particular, a high resistance to wear is provided by the use of ceramic materials.

It is pointed out here that, as an essential feature of the invention, all the above-mentioned components have been claimed as such and in any combination thereof, in particular as shown in the details of the figures. Modifications thereof will be familiar to those skilled in the art.

Reference numerals

10 electrosurgical instrument

11 extrusion part, branch

11a clamping part

12 extrusion part, branch

12a clamping part

13 distal end

14 distal end

15 proximal end

16 proximal end

17 Current supply device

17a connecting element

18 electrode assembly

18a cutting part

18b electrode surface

18c recess

19 electrode assembly

19a cutting part

20 short-circuit prevention device

21. 21' insulating part

22 cutting edge

23 arc of arc

30 tissue of

Claims

1. An electrosurgical instrument comprising

Two combined branches (11, 12) which can be driven in the manner of a press tool,

-electrode means (18, 19) at the distal ends (13, 14) of the branches (11, 12) for clamping tissue (30) and for conducting a coagulation current through the tissue (30) to cause coagulation thereof,

-current supply means (17) for supplying a coagulation current from the HF generator to the electrode members (18, 19) and

-at least one means (20) for preventing short-circuits, which is arranged on the electrode parts (18, 19) and is arranged and configured in such a way that the electrode parts (18, 19) cannot touch, and which comprises an insulation (21) on at least one electrode part (18, 19),

wherein at least one cutting section (18a, 19a) for cutting with an electric arc is arranged on at least one electrode part (18, 19),

and wherein the insulating part (21) is arranged on the cutting part (18a, 19a) or on an electrode part opposite to the cutting part (18a, 19a) and protrudes from the cutting part (18a, 19a) or an electrode part opposite to the cutting part (18a, 19a) in such a way that the electrode part (18, 19), the cutting part (18a, 19a) and the insulating part (21) are superposed on each other in the direction in which the branches (11, 12) move, so that the electrode parts (18, 19) are spaced apart by the insulating part (21) when the branches (11, 12) are brought together.

2. An electrosurgical instrument according to claim 1,

wherein

The device (20) for preventing short circuits provides a distance element as an insulation (21) on at least one of the electrode parts (18, 19).

3. Electrosurgical instrument according to claim 1 or 2,

wherein,

adjoining the insulation (21), on the at least one electrode part (18), at least one initial cutting section (18a) is arranged in such a way that, with any increase in the coagulation current voltage, an arc (23) for cutting into the tissue (30) is generated from the initial cutting section (18 a).

4. Electrosurgical instrument according to claim 1 or 2,

wherein,

the second cut portion (19a) is disposed on the electrode member (19) facing the electrode member (18) having the insulating portion (21).

5. Electrosurgical instrument according to claim 1 or 2,

wherein,

the insulating portions (21) are arranged in a symmetrical manner with respect to the initial cut (18a) and/or the second cut (19a) on the respective electrode parts (18, 19).

6. An electrosurgical instrument according to claim 2,

wherein,

the distance elements are configured in such a way that a mechanical cutting can be carried out.

7. Electrosurgical instrument according to claim 1 or 2,

wherein,

the cut (18a, 19a) on at least one electrode part (18, 19) is configured as a blade edge having a substantially triangular cross-section.

8. Electrosurgical instrument according to claim 1 or 2,

wherein,

the cut (18a, 19a) on at least one electrode part (18, 19) is configured as a blade edge with a circular cross section.

9. Electrosurgical instrument according to claim 1 or 2,

wherein,

the insulating part (21) is made of a material resistant to arc corrosion.

10. Electrosurgical instrument according to claim 1 or 2,

wherein,

the insulating part (21) is made of a ceramic material.