DE10028413A1 - Electro-surgical instrument consists of an electrode cable, an electrode, a core and an insulating mantle. - Google Patents

Abstract

An electro-surgical instrument consists of an electrode cable (5) and electrode (7) with a current supplying core (15), and an insulating mantle (9) which partially covers it. The free electrode surface (17) at one end section of the electrode is reduced. The mantle surrounding the electrode has a number of openings (23).

Description

The invention relates to an electrosurgical instrument, comprising an connected to a patient end of an electrode lead Electrode with a current-carrying electrode core and one of the elec trode core partially covering insulating jacket.

Such an electrosurgical instrument, also known as a high frequency surgical, monopolar connected electrode can, in the form of a loop electrode, is from the German design Scripture 21 32 808 known and often found as an additional facility for Endoscopes use to growths, for example gastric and Intestinal polyps to ablate. This is done by the growths Pulling the connected to a power source via the electrode lead its loop electrode can be separated by electrotomy.

The known loop electrode type has two loop sections, that merge integrally into one another at the electrode tip. In the area of Electrode tip is provided a semi-circular bend that the Spread the loop sections as they slide out of the tube as well as being drawn into the tube.

From German published patent application 28 08 546 is a with high frequencies zenergie powered electrosurgical instrument known for Cutting structures used in human body cavities becomes. This instrument includes a metal cable that is made out of a bend Actuating wire and a straight cutting wire consists. An insulating jacket is provided on the actuating wire,  which prevents adjacent tissue from being injured during the cutting process or is accidentally cut.

In the case of a loop electrode, for example, is enough to heat the tissue the amperage provided by the energy source is often not for a clean, bleeding-free coagulation cut with the Schlin gene electrode. The separation process is rather there completed by that the growth to be separated by the one pull the loop electrode into the tube and consequently through the one with the Reduction of the area spanned by the loop electrode the pinching effect of the loop sections is plucked off. In the There are limits to using stronger energy sources than that increased electrical energy in the case of the person to be treated Patients to inconvenience to health damage can lead. There is also a use of stronger energy sources economic aspects regarding the manufacture of electrosurgery against instruments.

Proceeding from this, it is an object of the invention to provide an electrode gangs mentioned so that they improve even at low power strengthen a coagulation process to be gentle on the patient Way.

This object is achieved in that at least one partial area the free electrode surface of the electrode core by a a region of the insulating jacket containing a plurality of openings is reduced.

This gives an electrode, the free effective surface of which the perforated insulating jacket is reduced. Through this constructive Measure the current flow focuses on that from the openings free areas of the electrode. Even at a relatively low level  Current strength, the current density achievable at the openings is high enough, to ensure adequate coagulation of the treated tissue Afford.

An arrangement distributed over the area of the respective electrode area The openings ensure a sufficient overall size of the effective Electrode area. With the concentration of the degraded by the energy source ren current on the effective electrical limited by the insulation The surface area is usually designed for one energy source complication-free surgical intervention.

Preference is given to that in the region of the electrode having the openings Electrode surface through the insulating jacket by approx. 5 to approx. 95%, preferably more than 50%, particularly preferably around 70% to 80% reduced. The width of the openings, corresponding to the average through knife if the openings are about the same width as long or the width elongated gap-shaped openings, can be 0.01 to 0.5 mm, or 0.01 to 50 times, preferably 1.1 to 10 times, particularly preferably 0.5 to 2 times the average thickness of the insulating jacket. The layer thickness of the insulating jacket is preferably 0.02 to 0.3 mm, particularly preferably 0.05 to 0.12 mm.

The openings in the insulating jacket can be different Way. So you can about the layer of insulating material First apply the closed surface and precisely pre-open the openings of a certain shape, especially mechanically or by exposure to radiation, for example using a laser. Also photolithogra Fish techniques come into consideration. Another way to get here Position of the openings is that on the electrode core behind each other rings of insulating material are placed so that between the ring gaps remain, which are then the effective electrodes form open openings. To get a tight fit this  To ensure rings on the electrode core, the rings can be made heat-shrinkable material formed after putting on the electrode core has shrunk.

There is also the option of initially closing the electrode core to be coated with hardening or hardenable insulating material and then deform the electrodes so that the insulating jacket cracks gets. This process is particularly economical.

The insulating jacket can be sprayed, sputtered onto the electrode core, painted, extruded or applied by dipping. It also exists the possibility of spraying or sputtering the openings Droplets to form a non-closed layer of insulating material, which the Keeps manufacturing effort very low.

The insulating jacket can be made of lacquers, polyamides, or polyimides be formed from a fluoroplastic, in particular from FEP, ETFE, ETCFE, PCTFE, PEEK, preferably MFA, PFA or a mixture of at least two of these materials.

The electrode configuration according to the invention is for a variety of Suitable electrode shapes, including the loops mentioned above electrodes, but massive electrode bodies are also possible, ins special balls with a diameter of, for example, 1 to 5 mm or knife-like bodies with a length of preferably 1 to 15 mm (scalpel-like instruments), or elongated, approximately rod-shaped Body, or flattened body, rounded around the circumference.

The electrode can also be moved into a pliers-like manner Electrode pair to be divided.  

The instrument can be used externally, in which case the Electrode over an elongated neck with an insulating jacket an insulating handle part can be connected, or for endoscopy application, the covered neck being more rigid or flexible Rod can be executed. The preferred application is monopolar electrodes to be operated, in which the electrode forms the one pole and the patient's body the other. The electrode core can too for bipolar operation in two or more differently polarized Ab cuts can be divided.

The invention further relates to an electrochi in a second aspect rurgisches Instrument comprising a at least externally insulating Tu bus, an electrode lead that can be moved in the tube and one with loops connected to the patient end of the electrode lead electrode with two electrically connected together, between two end of the electrode lead and one of the Electrode lead from far electrode tip extending loops cuts that spread out from the tube and spread out by means of the electrode lead completely or almost completely in the Tubes are retractable.

Such an electrosurgical instrument, also known as a high frequency called surgical, monopolar connected loop electrode can be, is known from the German Auslegeschrift 21 32 808 and is primarily used as an additional device for endoscopes To remove growths, for example gastric and intestinal polyps. This happens by pulling the growths over the electro loop wire connected to a power source be separated by electrotomy.

The known loop electrode type has two loop sections, that merge integrally into one another at the electrode tip. In the area of  Electrode tip is provided a semi-circular bend that the Spread the loop sections as they slide out of the tube as well as being drawn into the tube.

From German published patent application 28 08 546 is a with high frequencies zenergie powered electrosurgical instrument known for Cutting structures used in human body cavities becomes. This instrument includes a metal cable that is made out of a bend Actuating wire and a straight cutting wire consists. A contact means is provided on the actuating wire during the cutting process prevents neighboring tissue from being injured or is accidentally cut.

The heating of the loop electrode from the energy source to the ver current is often not sufficient to ensure a clean, perform bleeding-free coagulation cut with the loop electrode ren. The separation process is rather completed by the fact that the growth to be separated by pulling in the loop electrode in the tube and consequently by reducing the number of the Loop electrode spanned surface associated pinching effect of the Loop sections is plucked. When using stronger energy Sources are limited in that the increased electrical energy may cause discomfort to the patient being treated can lead to damage to health. There are also one Use of stronger energy sources regarding economic aspects against the manufacture of the electrosurgical instrument.

Proceeding from this, the object of the invention is a loop electrode to improve the known type so that it involves a coagulation process in a way that is gentle on the patient.  

This object is achieved in that the effective Electrode surface of the loop electrode through an insulating jacket two loop sections on a section near the electrical the tip is limited.

Advantageous developments of the invention are in the subclaims specified.

The inventive teaching consists essentially in the effective elec tread surface of the loop electrode only by a design measure to concentrate on that surface area of the loop electrode which is the thermal generated by the flow of electrosurgery Cutting process of the loop electrode should ideally take place. This constructive limitation of the effective electrode area by means of ver at least partially isolating the two loop sections significantly simplifies the handling of the electrosurgical instrument because the risk of incorrect cuts or unwanted contacts with healthy Neighboring tissue is reduced to a minimum.

Only the area of the loop elector which is kept free from the insulation trode, which is based on the wealth of experience for the corresponding surgical intervention at an optimal point on the loop electrode is determinable, comes with proper use of the electrosurgery instruments with the growth of a patient to be removed Contact. This ensures that only this limit th area for heating the loop electrode for a clean Coagulation cut required current flows and therefore a concentrator tere use of the energy source connected to the loop electrode is realized.

With the concentration of the current intensity that can be emitted by the energy source to the effective electrode area of the  Loop electrodes are sufficient for the usually designed energy sources for a complication-free surgical procedure. The effective one Electrode area is necessary because of the cutting process retraction of the loop electrode into the tube necessarily in to arrange the area of the loop electrode close to the patient, wherein within this range the location of the effective electrode area for different loop electrodes vary depending on the surgical procedure can be.

In terms of economic aspects, it is advantageous to use the two Schlin gene sections full to the area of the effective electrode area to be constantly surrounded by the insulating jacket. Here, the limit te, effective electrode surface either by subsequent removal the insulation jacket with the help of, for example, a scalpel or at Apply the insulation by covering the elec tread surface are created.

To areas of uncovered electrode areas that are not for the Koagu lation process of the respective growth are provided on a mini mum, it is advantageous to limit the effective electrode area in the to be arranged essentially on the inside of the loop. In this case it remains the loop outside in the area of the effective electrode surface insulation provided, in a particular embodiment of the electrosurgical instrument more than half the circumferential surface of the Loop electrode on the effective, limited electrode area of the Insulation jacket is surrounded. In certain cases, however, it can it may be necessary that the insulating sheath on the effective electrode surface less than half the circumferential surface of the loop electrode surrounds. For manufacturing reasons, it can be used for certain Loop electrodes should be sufficient on the effective electrode area completely remove the insulation jacket.  

In an advantageous embodiment of the electrosurgical instrument is an effective electrode area on both loop sections in particular provided symmetrically.

The limitation of the effective electrode area of the loop electrode an insulating jacket can reali both for loop electrodes Siert, the loop sections at the electrode tip integral merge into one another, as well as for those whose electrode leads End areas facing away engage in a sleeve and through the latter are firmly connected to one another in an electrically conductive manner. When using With such a sleeve, it is advantageous to remove the end regions of the loops cuts do not completely free of the insulation as the fasteners property of the sleeve to peel off the exposed insulation the end portions of the loop sections prevented.

Especially in areas where the insulating jacket is the electrical only partially surrounds the circumferential surface of the loop electrode is a Anchoring means for the firm positioning of the insulating jacket seen. Such anchoring means can be at the end regions of the loop sections are provided sleeve. At Schlingenelek tread with loop sections that have an integra at the tip of the electrode len transition, the anchoring means by a pla static deformation, in particular by an approximately circular Bending or kinking the loop electrode near the electrodes be formed tip. One goes with the deformation of the loop electrode Cross-sectional change on the deformed, in particular curved or ge buckled, area hand in hand. The loops, which are mostly circular in cross-section electrodes are in the plastically deformed, in particular curved or kinked area, flattened - d. H. in one cross-sectional direction there is an increase in diameter, while in the other cross cutting direction a reduction in diameter compared to the ver shaped loop electrode is present. It is this cross-sectional change that  a displacement of the insulating jacket relative to the loop electrode prevented.

Another anchoring means can be realized in that at least that electrode surface of the loop electrode on which the insulating jacket is applied, is provided with depressions. Such depressions are available when using a wire rope Strand structure for the loop electrode available, the on the Outside of the wire rope, formed by two adjacent strands grooves form the anchoring recesses.

The insulating jacket for the loop sections of the invention electrosurgical instrument can be extruded, painted or injection molded his. As a material for the insulating sheath, PEEK, fluor art substances are used, in particular FEP, ETFE, ECTFE, PCTFE, where MFA or PFA plastics are preferred.

Further advantages, features and properties of the invention are Description of preferred embodiments of the invention based on the accompanying drawings, in which show:

FIG. 1 is a cross-sectional view showing the loop electrode side region represents an electrosurgical Instru ments according to the invention schematically, with substantially kreisförmi gen openings in the insulation;

Fig. 2 is a cross-sectional view along section line II-II of Fig. 1;

Fig. 3 shows schematically a variant of the instrument of Fig. 1;

Fig. 4 is a view similar to Figure 1, but in which the Isolierungsöff openings are formed by cracks.

FIG. 5 shows an instrument similar to Figure 1, but with annular gap-shaped openings in the insulation.

FIG. 6 shows a cross-sectional view along section line VI-VI in FIG. 5;

Fig. 7 is a cross-sectional view according to section line VII-VII in Fig. 5;

Fig. 8 is a view of a spherical electrode head of an elec trochirurgischen instrument according to another embodiment;

Fig. 9 is a view of a blade-like electrode head guiding a elec trochirurgischen instrument according to still another Off;

10a is a side view of a pincer-like electrode head of an electrosurgical instrument according to still another embodiment.

Fig. 10b shows a view according to arrow X in Fig. 10a;

FIG. 11 is a cross-sectional view showing the loop electrode side portion of an electrosurgical Instru mentes invention according to the second aspect of the invention schematically illustrating;

FIG. 12 is a cross-sectional view according to section line II-II of FIG. 11;

FIG. 13 is a cross-sectional view along the section line III-III of FIG. 11;

FIG. 14 is a cross-sectional view illustrating the area of the electrode tip of an electrosurgical instrument according to the invention in a further embodiment of the second aspect schematically;

FIG. 15 is the area of the electrode tip of an electrosurgical instrument according to the invention in a further exporting approximate shape of the second aspect;

Fig. 16 is a cross-sectional view of an electrosurgical instrument according to the invention in a further embodiment specific to the area of the electrode tip according to the second aspect matically; and

FIG. 17 is a view of the region of the electrode tip shown in FIG. 16 in the direction of arrow VII in FIG. 16.

The portion of an electrosurgical instrument 1 shown in Fig. 1 comprises a flexible and insulating outer tube 3, which is made of poly-tetra-fluoro-ethylene. The tube 3 can also be made of a rigid Isolierma material. In the flexible tube 3 , a flexible electrode lead 5 is slidably guided, which is coupled to an actuator (not shown) at its far end from the patient and is electrically connected to an energy source (not shown). The electrode line 5 can also be rigid.

The near-patient end 66 of the electrode lead 5 carries an axis symmetrical to Tubu loop electrode 7 with two remote from the patient between the end 6 of the loop electrode 7 and the electrode lead 5 distal electrode tip extending loop portions 9 and 11. FIG. The loop electrode 7 is displaceable relative to the tube 3 via the actuating device (not shown) and the electrode feed line 5 coupled to the latter, so that its loop sections 9 , 11 for spreading around the growth of the patient to be treated (not shown) spread apart resiliently as soon as they are removed are pushed out of the tube 3 , and they are completely retractable into the tube 3 to carry out the coagulation process.

In the extended state, the loop electrode 7 can assume other loop shapes in addition to the shape shown in FIG. 1. In particular, a hexagonal loop shape (not shown) or a loop shape (not shown) which is angled to the longitudinal axis of the part of the electrode lead 5 near the patient, which is used advantageously in cutting difficult-to-reach growths.

The loop sections 9 , 11 span a flat loop plane, the longitudinal axis of the part of the electrode lead 5 near the patient lying in the loop plane. The position of the loop level does not change compared to the patient-near part of the electrode lead 5 when pulling the loop sections 9 , 11 essentially.

The loop sections 9 , 11 are attached to the patient distal end 6 of the electrode lead 5 by means of a metal sleeve 13 to the latter and electrically coupled. In the embodiment of the loop electrode 7 according to FIG. 1, the patient-oriented ends of the loop sections 9 , 11 merge integrally into one another.

The structure of the loop sections 9 , 11 is clear from FIGS. 2 and 3. The loop electrode 7 is formed by a wire cable 15 which carries the electrical current and has a (1 × 4) strand structure. Other strand structures (1 × 7, 3 × 7, 1 × 9) can also be used. Except for an effective electrode surface 17, the wire rope 15 is completely surrounded by an insulating sheath 19 (see FIG. 2).

In the loop electrode 7 of FIG. 1 is the effective area of electrodes, which are limited outwardly exposed surface portions 17 of the wire rope 15 by a plurality of distributed openings 7 through the loop 23 in the insulating sheath 19th The openings here are, at least on average, about as wide as they are long. The distribution density of the openings 23 can be uniform over the entire loop 7 or can be denser at the actual cutting area of the loop, namely the tip 21 , than at the remaining loop sections 9 and 11 . The openings can also be provided only in the area of the tip 21 and / or predominantly on the inside of the loop, while the insulation remains completely closed in the remaining areas of the loop. In the loop area containing the openings 23 , the outwardly facing surface of the wire 15 is reduced by approximately 50%, preferably 70 to 80%, by the insulating sheath between the openings 23 .

An advantage when using a wire rope 15 with a strand structure is evident with regard to the anchoring of the insulating jacket 19 , in particular next to the openings 23 in the insulating jacket 19 . The groove 29 lying between two adjacent strands 25 , 27 is filled when the insulating material is applied to the wire rope 15 . The insulating material takes the contour of the groove 29 and thus the shape of a tapering mandrel, which cooperates with the groove 29 of the wire rope 15 anchoring. Such an anchoring means prevents the insulating sheath 19 , 23 from slipping off the loop electrode 7 , especially when it is being used, and thereby exposing the electrode surface which could possibly impair healthy patient tissue.

In plan view, at least on average, the openings can be essentially as long as they are wide, for example approximately circular or polygonal, or they can also be elongated, with an average opening diameter or average gap width of 0.01 to 0.5 mm , The layer thickness of the insulating sheath on the wires 15 outside the groove 29 is approximately 0.02 to 0.3 mm. The insulating jacket can be sprayed on from plastic, optionally subsequently heat-treated (sintered) at a temperature of 300 to 400 ° C., in particular in the case of PTFE, or also by immersion treatment. In the case of spraying not covering the entire area, the remaining gaps form the openings 23 . If the insulating jacket is applied across the entire area, the openings are subsequently machined mechanically or using a laser. Preferred insulating materials are fluoroplastics, such as FEP, PFA (which is particularly easy to spray and highly sticky), or PEEK, polyimides and others.

Fig. 3 shows a construction variant in the manner of a papillotome, in which an electrode wire 7 a is stretched between the free end of an arc 31 held on a tube or free handle 3 a.

FIG. 4 shows the tip 25 of a loop electrode similar to FIG. 1, but in a variant in which the wire 15 is coated with a hardenable plastic or lacquer in a densely insulating manner before it is deformed. After the insulating jacket has hardened, the wire 15 is formed , approximately bent and stretched, with cracks 23 'being formed in the relatively hard insulating jacket, which then define the effective electrode area. The direction of bending or deformation for producing the jumps 23 'can coincide with the deformation direction for obtaining the electrode loop which is ready for operation, but can also be different, as a result of which the direction and orientation of the jumps 23 ' - towards the inside or outside of the loop - to be able to control, such that the jumps are at least predominantly on the inside of the loop.

Fig. 5 shows an instrument similar to Fig. 1, but the insulating jacket 19 is formed from a plurality of successively shrink-fitted and subsequently heat-shrunk shrink-tube sections 19 "which are plugged onto the wire cable. Gaps remain between the ends of adjacent shrink-tube sections 19 ", 19 " 23 ", in which the wire 15 is exposed, so that the gaps 23 " define the effective electrode areas (cf. FIG. 7). The gap density can be constant over the loop length or can also be variable, in particular in the region of the tip 21 denser than on the remaining loop sections 9 , 11. Otherwise, the structure of this electrode corresponds to the electrode of Fig. 1, so that reference is made to the associated description.

Fig. 8 shows a rigid electrosurgical instrument with a kugelför shaped electrode 41 which is attached to the free end of an insulated rod-shaped neck 43 . The neck 43 is attached to a handle 45 . The electrode lead 5 leads away from the rear end of the handle. The electrode 41 has a diameter of about 1 to 5 mm and is used for hemostasis, desolation of tissue, removal of warts, etc. The insulating jacket of the ball and the openings therein 23 correspond to the embodiment of FIG. 1. On the associated description is referred.

FIG. 9 shows an instrument similar to FIG. 8, but with a knife-like or scalpel-like electrode 41 'with a length of 1 to 15 mm. The neck 43 , the handle 45 and the electrode lead 5 correspond to FIG. 8.

Depending on the application, other electrode shapes are also possible, such as spoon-shaped, rod-shaped or rigid ring-shaped electrodes.

Figs. 10a and 10b show a pincer-like electrosurgical instrument in whose electrode te resiliently strained 51 in two away from each other, the end surface electrodes enlarged pliers 53, is partitioned 55th In this case, the two pliers 53 , 55 can be electrically connected to one another for monopolar operation, or electrically separated for bipolar operation. The handle and the electrode feed correspond to FIG. 8.

The part of an electrosurgical instrument 61 shown in FIG. 11 according to the second aspect comprises a flexible and externally insulating tube 63 , which is made of poly-tetra-fluoro-ethylene. The tube 63 can also be made of a rigid insulating material. In the flexible tube 63 , a flexible electrode lead 65 is slidably guided, which is coupled to an actuator (not shown) at its far end from the patient and is electrically connected to an energy source (not shown). The electrode lead 65 can also be rigid.

The near-patient end 66 of the electrode lead 65 carries an axis symmetrical to Tubu loop electrode 67 with two extending between the patient-remote end 6 of the loop electrode 67 and the electrode lead 65 distal electrode tip extending loop portions 69 and 71st The loop electrode 67 can be displaced relative to the tube 63 via the actuating device (not shown) and the electrode feed line 65 coupled to the latter so that its loop sections 69 , 71 for spreading around the growth of the patient to be treated (not shown) spread apart resiliently as soon as they are opened are pushed out of the tube 63 , and they are completely retractable into the tube 63 to carry out the coagulation process.

In the extended state, the loop electrode 67 can take other loop shapes besides the shape shown in FIG. 11. In particular, a hexagonal loop shape (not shown) or a loop shape angled to the longitudinal axis of the part of the electrode lead 65 near the patient (not shown) may be mentioned, which is advantageously used in cutting growths that are difficult to access.

The loop sections 69 , 71 span a flat loop plane, the longitudinal axis of the part of the electrode lead 65 near the patient lying in the loop plane. The position of the loop plane does not change compared to the patient-near part of the electrode lead 65 when pulling the loop sections 69 , 71 substantially.

The loop sections 69 , 71 are attached to the patient distal end 66 of the electrode lead 65 by means of a metal sleeve 73 to the latter and electrically coupled. In the embodiment of the loop electrode 67 according to FIG. 11, the patient-oriented ends of the loop sections 69 , 71 merge integrally into one another.

The structure of the loop sections 69 , 71 is clear from FIGS. 12 and 13. The loop electrode 67 is formed by an electric current-carrying wire rope 75 , which has a (1 × 4) strand structure. Other strand structures (1 × 7, 3 × 7, 1 × 9) can also be used. Except for an effective electrode surface 77, the wire rope 75 is completely surrounded by an insulating sheath 79 (see FIG. 12).

When performed according to the Fig. 11 loop electrode 67 ver the effective electrode area 77 runs from the electrode tip 81 along the inside of the left loop section 69. With a length of the loop section 69 of approximately 80 mm, a possible effective electrode surface 77 has a length of approximately 5 mm. In the area of the effective electrode surface 77 , a section 83 of the insulating jacket 79 is provided on the outside of the loop section 69 , so that the effective electrode surface 77 both along the loop section 69 through the insulating jacket 79 and on the circumference of the loop section 69 through the section 83 of the insulating jacket 79 is limited. As shown in FIG. 13, the section 83 of the insulating sheath 79 comprises more than half of the wire rope circumference, the remaining insulating material-free area defining the effective electrode area 77 .

An advantage when using a wire rope 75 with a strand structure is evident with regard to the anchoring of the insulating sheath 79 , in particular of the section 83 of the insulating sheath 79 . The groove 89 lying between two adjacent strands 85 , 87 is filled when the insulating material is applied to the wire rope 75 . The insulating material takes on the contour of the groove 89 and thus takes the form of a tapering mandrel, which interacts with the groove 89 of the wire rope 75 to anchor. Such an anchoring means prevents the Isolierumman telung 79 , 83 from the loop electrode 67 slipping, especially when they are used, thereby exposing the electrode surface that could possibly impair healthy patient tissue.

In an alternative embodiment of the loop electrode 67 , the right loop section 71 is also seen with an effective electrode area, which is indicated by dashed lines in FIG. 11. In this way, an effective electrode surface extends on the inside of the loop electrode 67 from one loop section 69 , 71 over the electrode tip 81 to the other loop section 71 , 69 .

Such an embodiment is shown in FIGS. 16 and 17, identical or similar components being provided with identical reference numerals and an additional letter "a" and, because of their identical or similar function, need not be explained again. This symmetrical, effective electrode surface 77 a is produced by stripping a full-surface insulation.

To give the loop electrode 7 , 7 a according to FIGS. 11 and 16 the necessary spring force for spreading the loop sections 69 , 69 a, 71 , 71 a after pushing out of the tube 63 , the loop electrode 67 , 67 a has on them Tip 81 , 81 a a plastically deformed area 91 . The plastic deformation causes a flattening of the wire rope with a cross-sectional constriction or widening, which as a further Ver anchoring means a displacement of the section 83 , 83 a of the Isolierumman telung 79 , 79 a prevented from the loop electrode 67 , 67 a away.

In the embodiment of the loop electrode 67 b shown in FIG. 14, its identical or similar components are provided with identical reference numerals and an additional letter "b" and do not need to be explained again because of their identical or similar function. The loop electrode 67 b comprises loop sections 69 b, 71 b with end regions 93 , 95 near the patient. Starting from the end regions 93 , 95 , the section 83 b of the insulating sheath 79 b extends along the two loop sections 69 b, 71 b and the full-surface insulation sheath 79 b adjoins this. The end regions 93 , 95 are firmly gripped by a sleeve 97 , an electrical contact being made between the loop sections 69 b, 71 b insofar as their contact surfaces 99 , which are free of insulating material, touch. In addition, the sleeve 97 serves as anchoring means for the section 83 b of the insulating jacket 79 b. The effective electrode surfaces 77 b run on the inside of the loop sections 69 b, 71 b from the respective insulating jacket 79 b to their common contact surface 99 .

In the embodiment of the loop electrode 67 c shown in FIG. 15, its identical or similar components are provided with identical reference numbers and an additional letter "c" and do not need to be explained again because of their identical or similar function. The loop sections 69 c, 71 c are completely freed from the insulating sheath 79 c on the effective electrode surface 77 c over their entire circumference. Only at the electrode tip 81 c remains an insulating jacket 101 , which covers the inside of the loop as small an electrode area as possible, while covering the outside of the loop to protect the healthy tissue of a patient, the largest possible electrode area.

Claims (37)

1. Electrosurgical instrument, comprising an electrode ( 7 , 7 a, 41 , 41 ', 51 ) connected to a patient-near end of an electrode lead ( 5 ) with a current-carrying electrode core ( 15 ) and
an insulating jacket ( 19 ) partially covering the electrode core ( 15 ),
characterized in that the free electrode area ( 17 ) of the electrode core ( 15 ) is reduced on at least a portion ( 21 ) of the electrode by a portion of the insulating jacket ( 19 ) containing a plurality of openings ( 23 , 23 ', 23 "). 2. Electrosurgical instrument according to claim 1, characterized in that in the openings ( 23 , 23 ', 23 ") containing portion ( 21 ) of the insulating jacket the free electrode surface through the insulating jacket ( 19 ) by about 5 to about 95%, preferably more than 50%, particularly preferably reduced by about 70% to 80%. 3. Electrosurgical instrument according to claim 1 or 2, characterized characterized that the width of the openings is about 0.01 to 0.5 mm is. 4. Electrosurgical instrument according to one of the preceding claims, characterized in that the width of the openings is 0.01 to 50 times, preferably 1 to 10 times, particularly preferably 0.5 to 2 times the thickness of the insulating jacket ( 19 ), in particular at a layer thickness of 0.02 to 0.3 mm, preferably 0.05 to 0.12 mm. 5. Electrosurgical instrument according to one of the preceding claims, characterized in that the openings ( 23 ) are subsequently introduced into a previously applied insulating material layer. 6. Electrosurgical instrument according to claim 5, characterized in that the openings ( 23 ) are introduced mechanically or by radiation, in particular by means of a laser. 7. Electrosurgical instrument according to one of claims 1 to 4, characterized in that the openings are formed by deformation, in particular bending or stretching, of the insulated electrode core cracks ( 23 ') in the insulating jacket ( 19 '). 8. Electrosurgical instrument according to claim 7, characterized in that the insulating jacket ( 19 ') is brittle before the deformation of the electrode core to a degree allowing crack formation. 9. Electrosurgical instrument according to one of the preceding claims, characterized in that the insulating jacket ( 19 , 19 ') is sprayed, sputtered, lacquered, extruded or applied by dipping onto the electrode core. 10. Electrosurgical instrument according to one of claims 1 to 4, characterized in that on the electrode core ( 15 ) one behind the other rings ( 19 ") of insulating material are placed and between the rings ( 19 ") remaining column ( 23 ") the effective Electrode surface form open openings. 11. Electrosurgical instrument according to claim 10, characterized in that the rings ( 19 ") are formed from heat-shrinking material, in particular shrink tubing, and after being placed on the electrode core ( 15 ) are shrunk. 12. Electrosurgical instrument according to one of claims 1 to 4, characterized in that the openings ( 23 ) are formed by applying, in particular spraying or sputtering, droplets to form a non-planar closed insulating material layer. 13. Electrosurgical instrument according to one of the preceding claims, characterized in that the insulating jacket ( 19 ) is formed from lacquer, polyamides, polyimides or a fluoroplastic, in particular from FEP, ETFE, ECTFE, PCTFE, PEEK, preferably from MFA, PFA or one Mixture of at least two of these materials. 14. Electrosurgical instrument according to one of the preceding claims, characterized in that the electrode ( 15 ) forms an at least partially retractable loop ( 7 ) in a tube ( 3 ). 15. Electrosurgical instrument according to claim 14, characterized in that the electrode region containing the openings ( 23 ) is located on the apex ( 15 ) of the loop ( 7 ) not drawn in close to the patient. 16. Electrosurgical instrument according to claim 14 or 15, characterized in that the electrode containing the openings ( 23 ) is located essentially on the inside of the loop. 17. Electrosurgical instrument according to one of claims 1 to 13, characterized in that the electrode forms a solid body ( 41 , 41 '). 18. Electrosurgical instrument according to claim 17, characterized in that the electrode forms a round body ( 41 ), in particular a ball, or a knife-like body ( 41 '). 19. Electrosurgical instrument according to one of claims 1 to 13, characterized in that the electrode ( 51 ) is divided into a pair of electrodes ( 53 , 55 ) which can be moved towards one another in the manner of forceps. 20. Electrosurgical instrument according to one of claims 17 to 19, characterized in that the electrode is attached to an insulating handle part ( 45 ) via an insulating coated, elongated neck ( 43 ). 21. Electrosurgical instrument according to claim 20, characterized in that the covered neck ( 43 ) is rigid or flexible leads out. 22. Electrosurgical instrument according to one of the preceding Claims, characterized in that the electrode in the Instrument forms a monopolar electrode. 23. Comprehensive electrosurgical instrument

• - an at least externally insulating tube ( 63 ),
• - In the tube ( 63 ) displaceable electrode lead ( 65 ) and
• - one with the patient-side end (66) of the Elektrodenzulei device (65) loop electrode connected (67, 67 a, 67 b, 67 c) having two electrically conductively connected to one another, between the end nearest the patient (66) processing the Elektrodenzulei (65) and one of the electrode lead ( 65 ) distal electrode tip ( 81 , 81 a, 81 b, 81 c) extending loops ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c), the spread out from the tube ( 63 ) and are spring-loaded and can be completely or almost completely drawn into the tube ( 63 ) by means of the electrode feed line ( 65 ),

characterized in that
the effective electrode area ( 77 , 77 a, 77 b, 77 c) of the loop electrode ( 77 , 77 a, 77 b, 77 c) by an insulating jacket ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) of the two loop sections ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c) limited to a partial area in the vicinity of the electrode tip ( 81 , 81 a, 81 b, 81 c) is. 24. Electrosurgical instrument according to claim 23, characterized in that the insulating sheath ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) of the two loop sections ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c) the latter to the area of the effective electrode area ( 77 , 77 a, 77 b, 77 c) surrounds. 25. Electrosurgical instrument according to one of claims 23 or 24, characterized in that the effective electrode surface ( 77 , 77 a, 77 b) essentially on the inside of a loop section ( 69 , 69 a, 69 b, 71 , 71 a, 71 b) lies. 26. Electrosurgical instrument according to one of claims 23 to 25, characterized in that on the effective electrode surface ( 77 , 77 a, 77 b) of the loop electrode ( 67 , 67 a, 67 b) more than half the peripheral surface of the respective loop section ( 69 , 69 a, 69 b, 71 , 71 a, 71 b) is surrounded by the insulating jacket ( 83 , 83 a, 83 b). 27. Electrosurgical instrument according to one of claims 23 to 25, characterized in that on the effective electrode surface ( 77 , 77 a, 77 b, 77 c) of the loop electrode ( 67 , 67 a, 67 b, 67 c) less than that Half of the circumferential surface of the respective loop section ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c) is surrounded by the insulating jacket ( 83 , 83 a, 83 b), preferably the peripheral surface of the respective Schlin gene section ( 69 c, 71 c) of the insulating jacket ( 79 c) is free. 28. Electrosurgical instrument according to one of claims 23 to 27, characterized in that in each case an effective electrode surface ( 77 a, 77 b, 77 c) on both loop sections ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c) is seen before. 29. Electrosurgical instrument according to one of claims 23 to 28, characterized in that at the electrode tip ( 81 , 81 a, 81 c) the loop sections ( 69 , 69 a, 69 c, 71 , 71 a, 71 c) merge integrally into one another , 30. Electrosurgical instrument according to one of claims 23 to 29, characterized in that the two loop sections ( 69 b, 71 b) each have an end region ( 93 , 95 ) facing away from the electrode feed line ( 65 ), these end regions ( 93 , 95 ) engage in a sleeve ( 97 ) and are firmly connected to one another in an electrically conductive manner. 31. Electrosurgical instrument according to one of claims 23 to 30, characterized in that in the area of the effective electrode surface ( 77 , 77 a, 77 b, 77 c) an anchoring means for firmly positioning the insulating jacket ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) is provided on the respective loop section ( 69 , 69 a, 69 b, 69 c, 71 , 71 a, 71 b, 71 c). 32. Electrosurgical instrument according to one of claims 23 to 31, characterized in that an anchoring means for firmly positioning the insulating sheath ( 83 b) on the respective loop section ( 69 b, 71 b) by a for firmly connecting the electrode lead ( 65 ) opposite end regions ( 93 , 95 ) of the loop sections ( 69 b, 71 b) provided sleeve ( 97 ) is formed. 33. Electrosurgical instrument according to one of claims 23 to 32, characterized in that an anchoring means for firmly positioning the insulating jacket ( 83 , 83 a, 83 c) on the respective loop section ( 69 , 69 a, 69 c, 71 , 71 a , 71 c) by a plastic deformation ( 91 ), in particular by bending or kinking, the loop electrode ( 67 , 67 a, 67 c) in the vicinity of the electrode tip ( 81 , 81 a, 81 c) is formed, the deformed , in particular curved or kinked, area of the loop electrode ( 67 , 67 a, 67 c) has a change in cross section, in particular a flattened cross section. 34. Electrosurgical instrument according to one of claims 23 to 33, characterized in that an anchoring means for firmly positioning the insulating jacket ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) on the loop electrode ( 67 , 67 a, 67 b, 67 c) is formed by recesses provided at least on that electrode surface of the loop electrode ( 67 , 67 a, 67 b, 67 c), onto which the insulating sheath ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) is to be applied. 35. Electrosurgical instrument according to claim 34, characterized in that the loop electrode ( 67 , 67 a, 67 b, 67 c) is a wire rope ( 75 ) with a strand structure, in particular a 3 × 7, 1 × 4, 1 × 9, preferably comprises a 1 × 7 strand structure, the grooves ( 89 ) lying on the outside of the wire cable ( 75 ) and formed by two adjacent strands ( 85 , 87 ) forming depressions. 36. Electrosurgical instrument according to one of claims 23 to 35, characterized in that the insulating sheath ( 79 , 79 a, 79 b, 79 c, 83 , 83 a, 83 b) on the loop electrode ( 67 , 67 a, 67 b, 67 c) is extruded, painted or sprayed. 37. Electrosurgical instrument according to one of claims 23 to 36, characterized in that the insulating jacket made of polyamides, polyimides or one Fluoroplastic is formed, in particular from FEP, ETFE, ECTFE, PCTFE, PEEK, preferably from MFA, PFA.