WO2011157824A1

WO2011157824A1 - Surgical instrument

Info

Publication number: WO2011157824A1
Application number: PCT/EP2011/060111
Authority: WO
Inventors: Wolfgang Haag
Original assignee: M T W - Endoskopie W. Haag Kg
Priority date: 2010-06-18
Filing date: 2011-06-17
Publication date: 2011-12-22
Also published as: RU2013102301A; JP2013529479A; KR20130137117A; DE202010008674U1; EP2582309A1

Abstract

The invention relates to a surgical instrument (20), comprising a pull/push element (2) guided in a sleeve (1) for transmitting a pulling/pushing force from an actuating device (3) disposed at one end of the sleeve (1) to a loop (4) disposed at the other end of the sleeve in order to move the loop (4) from a storage position, in which the loop (4) lies in an extended manner inside the sleeve (1), into a usage position, in which the expanded opening (5) of the loop (4) is located in front of the sleeve (1), and back into the storage position, wherein the loop (4) comprises two expansion limbs (6), which in the usage position are located partially in and in front of the sleeve (1) and together have an expanded V shape and which are more flexurally rigid at least in a direction that is transverse to the opening plane (5') than a loop arc (7) connecting the respective free ends (61) of the expansion limbs to each other, and wherein the pull/push element (2) is electrically conductive. For an advantageous development, at least one first longitudinal sub-section (21) of the loop arc (7), which in the storage position is located on the one longitudinal side of the loop (4), comprises an electrically insulating sheathing (23) or consists of an electrically insulating material, and at least one second longitudinal sub-section (22) of the loop arc (7), which in the storage position is located on the other longitudinal side of the loop (4), is electrically conductive, comprises no electrically insulating sheathing and is electrically conductively connected to the pull/push element (2) by means of at least one expansion limb (6).

Description

Surgical instrument

The present invention relates to a surgical instrument, preferably a radiofrequency surgical polypectomy snare, preferably for the removal of pathological tissue in hollow organs, with a pull / push element guided in a sleeve for transmitting a pulling / pushing force from one at the one end of the Sleeve arranged actuating means on a arranged at the other end of the sleeve loop to move the loop from a Verwahrstellung in which the loop in an extended position in the sleeve, in a use position in which the splayed opening of the loop in front of the sleeve and to shift back again, wherein the loop has two in the use position partially in and in front of the sleeve, spread together V-shaped expansion leg, which are at least in one direction transverse to the plane defined by the expansion limbs opening level more rigid than a respective free Ends of the spreader bar l interconnecting loop bow, and wherein the pull / push element is electrically conductive.

Such an instrument is known in the prior art from DE 10 2005 030 159 AI. It is preferably used in the field of so-called flexible endoscopy, wherein, while the loop is still in the storage position, it can be inserted through a free working channel of an endoscope with its distal end into a hollow organ of a human or animal body. There, the loop can be moved into the position of use and placed around a limited tissue raised and to be removed by an surrounding wall, such as a polyp. To separate the tissue, the loop is retracted to narrow its opening in the sleeve while at the same time by means of a connected high-frequency generator with high-frequency pulsating electric current (RF current) acted upon. The loop serves as an active electrode, that of an HF-current is flowed through. At another, generally remote location, the body to be treated can be connected to a so-called neutral electrode so that a potential difference to the surrounding tissue remains at the loop. With a sufficiently large potential difference, an electric arc is produced between the active electrode and the adjacent tissue, whereby the desired cutting effect occurs by means of pyrolysis. If the loop is moved and in particular pulled back into the sleeve, the tissue area can be separated and removed. In view of this mode of operation, one should speak of a high frequency surgical instrument or cutter for the field of flexible endoscopy, which may, for example, find application in the gastrointestinal tract. A requirement of such instruments is that, based on the effective loop length, a sufficiently high current is available, otherwise the so-called lead delay and tissue damage may occur. Since the current intensity usually generated by HF surgical generators is limited, this also sets a certain upper limit for the effective loop length. In practice, an upper limit for the size of the tissue area to be removed with such an instrument is thereby often predetermined. To make matters worse, that at a mere increase in the electrically effective loop length and the so-called. Perforation risk, ie the risk of unwanted contacts and damage to healthy tissue increases.

Against this background, the object of the invention is to further develop an instrument of the type mentioned in the introduction, so that in particular the restrictions described above can be avoided as far as possible.

The object is achieved according to the invention initially and essentially in conjunction with the features that at least a first longitudinal section of the loop loop, which is in the storage position on one longitudinal side of the loop and preferably in position adjoins the local expansion limb, has an electrically insulating sheath or consists of electrically insulating material and that at least a second length genteilabschnitt the loop loop, which in the Verwahrstellung located on the other longitudinal side of the loop and in particular positionally adjoins the local expansion limb, is electrically conductive, has no electrically insulating sheath and is electrically conductively connected by at least one spreader leg with the pull / push element. It follows that the loop loop is effective not cutting with its entire length, but only in one or more longitudinal sections. The amperage generated by a connected HF generator is therefore available exclusively for the one or the limited, cutting-effective length sections, while the length of the loop or the circumference of the loop as a whole can be further increased, including the non-cutting length sections. This makes it possible to wrap around larger tissue areas, in particular tissue areas with a diameter of more than 2 cm in diameter (for example, with a diameter of 3 or 4 cm or more) and by means of the one or more limited, cutting effective areas of the Separate sling in toto. At the same time is at the limited cutting areas a higher current or potential difference available, as would be the case if the entire loop would be formed as an active electrode. The cutting effective length can be dimensioned so that the risk of so-called. On-cut delay is limited or avoided. In addition, there is the advantage that the perforation risk can be reduced by the partially insulating coating. The instrument according to the invention can be used, for example, for the removal of polyps and to this extent be referred to as HF surgical polypectomy snare. The invention also relates to a surgical instrument, preferably a radiofrequency surgical polypectomy snare, comprising a pull / push member carried in a sleeve for transmitting a pulling / pushing force from an actuator disposed at one end of the sleeve to an actuator disposed at the other end of the sleeve Sling to displace the sling from a storage position in which the sling is in an extended position in the sleeve to a use position in which the spread opening of the sling lies in front of the sleeve and back again displaced together with the sling slidably supported in the sleeve when displacing the sling from its storage position into its own

Use position against a sleeve-fixed counter-attack occurs to exert a spreading effect on the loop, wherein the loop forms two in the use position partially in and before the sleeve lying V-shaped spread legs whose free ends are connected to a loop Schlingen, where at each engage the free ends of additional, substantially parallel to the expansion limbs extending tension elements which are connected to the displaceable relative to the expansion limbs stop, and wherein the pull / push element is electrically conductive. Such an instrument is also known from DE 10 2005 030 159 AI. Based on this, the object of the invention is again to advantageously develop such an instrument, so that in particular the restrictions described above can be avoided as far as possible.

The object is achieved according to the invention initially and essentially in conjunction with the features that at least a first length portion of the loop loop, which is in the storage position on the one longitudinal side of the loop and in particular positionally on the local spreads! connects, having an electrically insulating sheath or consists of electrically insulating material and that at least a second length portion of the loop loop, which is in the Verwahrstellung on the other longitudinal side of the loop and in particular positionally adjoins the local expansion limb, is electrically conductive, has no electrically insulating sheath and by means of at least one Spreizschenkels electrically Conductive is connected to the pull / push element. For the possible effects and advantages, reference is made to the preceding description. According to the design of the sling with expansion legs, the sling can be pressed with its tip against the wall of a body cavity. In this case, the less rigid loop bow bends, so that the area in the direction from the end of the sleeve on the apex of the loop immediately after the free ends of the expansion leg is a region of greatest deflection. This area is at the same time the area of the largest opening of the

Noose so that the splayed loop, bent at right angles at the right angle, can be lifted or pulled over the tissue area to be removed (eg a polyp). Regarding the aforementioned fiction, contemporary instruments are many ways to preferred training. At first, it is preferred that the first longitudinal section section and the second longitudinal section section each have half the length or each approximately half the length of the loop loop and / or in each case proceeding from a distal tip or vertex of the loop loop, preferably up to one of the two expansion legs, respectively. extend. For example, it is preferable to use a loop loop which acts as a cutting electrode on one or both sides of the loop opening. In particular, in conjunction with the described possibility to bend the less rigid loop bow, this offers advantages in handling and observation by an endoscope. There is the possibility ability that the distal tip of the loop loop has an electrically insulating sheath or consists of electrically insulating material or that the distal tip of the loop loop is electrically conductive and has no electrically insulating sheath. Thus, the distal tip may optionally be formed as a cutting active electrode or not. The spreading elements adjoining the loop loop are likewise part of the loop and delimit with their opening cross-section. A preferred development is seen in that the expansion element adjoining the first longitudinal section section of the loop loop is at least partially, preferably in a longitudinal section adjacent to the first longitudinal section section of the loop loop, or altogether has an electrically insulating jacket or consists of electrically insulating material and the other expansion element is electrically conductive and has no electrically insulating sheath. Although the insulated expansion element can have an electrically conductive core, it does not form an active electrode for the cutting process due to its external insulation. It is thus possible, for example, to completely insulate an entire loop half or loop side (relative to the feed direction or an imaginary longitudinal center line) and to completely form the second loop half or side as an active electrode. In addition, the cutting effective length or its length portion can be further reduced at the loop length by, for example, both spreading at least partially, preferably in a respective adjoining the loop bend length portion, an electrically insulating sheath. It would then be possible, for example, for only one or possibly several longitudinal sections of the loop loop to act as an active electrode. A further development is also conceivable in that both tension elements at least partially, preferably in a respective adjacent to the associated expansion limb longitudinal portion, or altogether have an electrically insulating sheath or consist of electrically insulating material. The electrically insulating sheath preferably extends in its relevant length region around the entire core cross-sectional circumference of the loop loop or, if appropriate, of the expansion limb and of the tension element. The electrically insulating sheath can be designed, for example, as a coating which, for example, comprises aluminum carbonate or consists of aluminum carbonate, which is body and tissue friendly. However, other other electrically insulating sheathing or coatings are used. It is regarded as suitable for handling if the electrically insulating coating is roughened on peripheral regions of the loop loop and / or the expansion limbs oriented toward the center of the loop and is made comparatively smooth on circumferential regions of the loop loop and / or the expansion limb oriented away from the center of the loop. A roughening can be given, for example, by small points, points, hooks or comparable microstructures. This facilitates grasping and holding or positioning the loop around tissue to be removed. With regard to the loop loop, there is the possibility that this is made, for example, of a monofilament, preferably elastically flexible, looped wire wire (for example of spring steel), the diameter of which, for example, being in the range of 0.3 to 0.5 mm (or even deviating). can amount. Alternatively, there is the possibility that the loop bow has, for example, a loop core of comparable overall diameter, which, however, is made of a plurality (for example from approximately 10 to 20) monofilaments twisted or twisted together of correspondingly smaller individual diameters. With regard to the expansion leg is preferably thought that these are formed of elastic strips of metal, which lie in the storage position with their broad side surfaces together. At least in areas which are to be used as an active electrode, the loop loop and the expansion leg (s) are preferably made of a metal, such as spring steel. It exists the possibility that the loop loop in the area of its tip forms a bay of acute loop or parallel Schlingenbogenab- cuts. There is the possibility that the tension elements acting on the free or front ends of the expansion limbs are formed by wire ropes. There is also the possibility that the stop is formed by a tube piece slidably mounted in the sleeve, through which tube piece the expansion legs protrude. It is considered to be expedient that the traction elements extend along the broad side surfaces of the side faces pointing away from one another

Spreizschenkel extend. There is the possibility that the free or front ends of the expansion limbs are in the direction of the apex of the loop in front of the region of the largest opening width of the loop. A preferred development is also seen in that at least the loop loop has a plurality of spaced-apart local thickenings and / or spaced, loop-inwardly directed hooks. The thickenings or hooks can be arranged as needed in the effective as an active electrode length sections and / or the electrically insulated lengths. In order to feed an HF current to the loop or the length section (s) acting as the cutting electrode, it is considered appropriate that at least the corresponding loop sections in the area of the loop loop and the expansion leg and the pull / push element designed as a rope or band consist of an electric consist of conductive material and are electrically conductively connected to an electrical contact of the actuator. A selected for RF power generator can be connected to the said electrical contact of the actuator. The components or components of the loop, which are electrically conductive, together form an electrically conductive loop core. With regard to the described electrically insulating jacket, there is the possibility, as also described, that in a cross-section oriented transverse to the loop longitudinal or longitudinal direction around the entire loop core circumference, that is to say on the circumference, it extends. Alternatively, it would be conceivable to provide the electrically insulating sheathing as an electrically insulating cover only in a limited circumferential range of the ski core or of the sling core cross section. It would thus be conceivable for the lateral surface of the loop core to be electrically conductively free at least circumferentially at the peripheral side facing the loop core section of the loop opening and at the peripheral edge facing away from the loop opening at least in the circumferential direction has an electrically insulating cover. In particular, it would be conceivable for the lateral surface of the ski core to be continuously electrically conductively exposed in the circumferential direction relative to the loop core cross-section at the circumferential half in the circumferential direction, and at the circumferential half facing away from the loop opening, carries an electrically insulating cover. This possible development relates on the one hand to the loop loop and the expansion leg, but can also be applied to the tension elements as needed.

For further possibilities of the preferred embodiment, reference is made to DE 10 2005 030 159 AI. The content of this document is hereby incorporated in full in the present application, also for the purpose of including features with claims.

The feature that at least a first length portion of the loop loop is in the storage position on the one longitudinal side of the loop, does not necessarily mean that the first length portion section on the entire length of the loop loop extends on one longitudinal side of the loop. Accordingly, the feature that a second length portion of the loop loop is in the custody position on the other longitudinal side of the loop, does not necessarily mean that the second length portion extends over the entire length of the loop loop on the other longitudinal side of the loop. Instead, these features determine only one layer of the respective length section. This means that as an alternative, in particular as an alternative to the preferred (ie unnecessary) development, embodiments fall within the scope of the claimed invention, in which the first longitudinal section and / or the second longitudinal section of the loop bend over less than extend half the length of the loop loop.

For example, there is the possibility that the first longitudinal section of the loop loop is adjacent to a third longitudinal section of the loop on the same longitudinal side of the loop, that the third longitudinal section extends from the distal tip of the loop loop to the first longitudinal section and that the third longitudinal section is electrically conductive, has no electrically insulating sheath and is electrically conductively connected to the pull / push element by means of at least one expansion limb. Thus, one side of the loop loop may be cuttingly effective in a forward or distal portion of its length due to its lack of insulation, while a proximal adjoining portion of the length of said side of the loop may not be cuttingly effective due to electrical isolation. With respect to the cutting effective longitudinal portion means (here and in the rest) the formulation that this is electrically conductively connected by at least one spreader leg with the pull / push element that in an electrical connection between the cutting active longitudinal section and the pull / push element at least one Expansion limb is electrically conductively integrated. Especially in connection with the above-described embodiment, only a preferred (ie not necessary) embodiment is seen in that the second length portion of the loop loop extends continuously from the distal tip of the loop loop to the expansion leg disposed on the same longitudinal side of the loop. Alternatively, there is the possibility that the second longitudinal section of the loop loop extends from the distal tip of the loop loop only to a fourth longitudinal section of the loop loop disposed on the same longitudinal side of the loop, wherein the fourth longitudinal section of the loop loop comprises an electrically insulating jacket or electrically insulative material and preferably extends to the expansion limb on this longitudinal side.

Also preferred, i. Not necessary is that the second length portion of the loop loop and the third length portion of the loop loop have the same length. In particular, it may be provided that the length of the second longitudinal section of the loop loop and the length of the third longitudinal section of the loop loop about 15% to 40%, more preferably about 20% to 30% and more preferably about 25% of the length of the loop loop in a range of the distal tip is up to a spreader leg.

The invention will be further described below with reference to the accompanying figures, which show preferred embodiments of the invention. It shows: the first, the loop end having a first embodiment of the instrument according to the invention in an enlarged view, wherein the loop is currently in the storage position; , Ib the other end of this embodiment with actuator;

Fig. 2a is a view according to FIG. La, wherein the loop is displaced into a position of use;

2b shows a representation according to FIG. Lb, but in the position of use.

3a shows a representation according to FIG. 2a, the loop being displaced into an expanded position;

FIG. 3b shows a representation according to FIG. 2b, but in the spread-open position; FIG.

Fig. 4 in Fig. 2a designated IV area in an enlarged view

5 shows the area designated by V in FIG. 3a in an enlarged view;

Fig. 6 is a perspective view of a spread according to FIG. 3

Noose, in which, due to a vertical pressure of the loop on a support, the loop-bow section is splayed approximately at right angles to the sleeve, whereby an opening of the width D adjusts;

Fig. 7 shows the loop of a second embodiment of the instrument according to the invention in a spread on about as Fig. 3a;

8 shows the loop of a third embodiment of the instrument according to the invention in a representation as in FIG. 7; 9 shows an enlarged cross-sectional view of the loop loop in an electrically insulated longitudinal section in the direction of view IX-IX according to FIG. 3a;

10 is a perspective enlargement of a longitudinal section of an electrically insulated loop loop, according to a further preferred embodiment;

Fig. 11 in magnification an alternative embodiment to the detail XI of Fig. 3a;

Fig. 12 is an alternative to the embodiment shown in Fig. 11; Fig. 13a,

13b the two ends of the instrument according to the invention according to a further preferred embodiment,

Fig. 14a,

14b shows the two ends of the instrument according to the invention according to a still further preferred embodiment,

Fig. 15a,

15b, the two ends of the instrument according to the invention according to a still further preferred embodiment and

Fig. 16a,

16b, the two ends of the instrument according to the invention according to yet another preferred embodiment. The elements of the surgical instrument 20 or cutting device of the embodiments consist of materials that are able to withstand the temperatures occurring during sterilization of the device. The sleeve 1 is made of a plastic, such as PTFT. The sleeve 1 is connected via form-closure elements, essentially via plug-in connections with an actuating device 3. This has a guide rail 16 which has at its end a Durchgriffsauge for a finger, in particular the thumb of the surgeon. On the guide rail 16, which is connected to the sleeve 1 in a thrust and tension-proof manner, there is a pull-push piece 17 which has two handle recesses located opposite to the pull-push piece 17 between two fingers of the surgeon to be able to hold.

Within the sleeve 1 is continuously an electrically conductive pull-push element 2, which is formed in the embodiment as a metal core, in particular in the form of a rope or a flat strip. If the tension-push piece 17 connected to the pull / push element 2 is displaced, then the pull-push element 2 shifts inside the sleeve 1. The pull-push piece 17 also carries an electrical contact 14, which is connected to a Terminal of a high frequency power generator can be connected, with which the pull / push element 2 and designated by the reference numeral 4 noose of

Cutting device can be energized to separate in the known manner, for example, polyps from the tissue carrying them by means of a coagulation current can. In the figures la, lb the two longitudinal ends of the instrument 20 according to the invention are shown according to a first preferred embodiment, wherein the intermediate longitudinal region in which the pull / push element 2 extends through the sleeve 1, not shown for clarity is. Likewise, for better illustration, the end shown in FIG. 1 a is enlarged in comparison to the end of the instrument shown in FIG. 1 b (consequently also having a comparatively larger diameter). The actuating device 3 also has a flushing opening 15, by means of which a flushing liquid or a gas can be introduced into the sleeve 1.

The end of the push-pull element 2 is in two, in the custody position shown in Figure la, in which the loop 4 rests in the sleeve 1, substantially parallel to each other extending expansion leg 6 over. The expansion limbs 6 are each flat, resilient metal strips which lie against one another with their broad side surfaces. The two expansion legs 6 are spring-biased and have a kink 18, so that they spread out when pulling out of the sleeve 1 V-shaped, as shown in Figure 2a. In the displacement of the loop 4 from the sleeve 1 of the storage position shown in Figure la, in which the loop 4 fully rests in an extended position in the sleeve, to the position shown in Figure 2a, in which the kinks 18 outside before lie the end of the sleeve 1, spread the two expansion leg 6 V-shaped, so that the loop bow 7, which can be referred to with regard to the vertex 11 thereon as a loop vertex bow 7 and with the free end of the sixth 'the expansion leg 6 are connected to spreads. The intermediate space between the spread-apart legs 6 also forms a region of the loop opening 5 with an opening plane 5 '. The loop opening 5 is closed by the loop vertex bow 7, which consists of a metallic wire rope and is less rigid than the two spreader tangs! 6. In this sense, the loop loop 7 and the two expansion legs 6 form the loop 4 or overlie the loop opening 5.

The vertex 11 of the loop vertex arc 7 forms a constriction in the form of a bay, with the two sections 11 'of this bay running at an acute angle to one another. Also, the respective area of the loop vertex arc 7, which is adjacent to the free end 6 ^{1 of} the expansion leg 6 forms a bulge 19 to the outside. As can be seen from FIG. 6, the two bulges 19 lie essentially diametrically opposite one another and form the region of the largest diameter D of the loop.

At the free ends 6 'of the expansion leg 6 each tensile elements 10 are also attached. These tension elements 10 are made of thin wire cables and, together with the expansion legs 6, project through a tubular counter-abutment 9, which is arranged so as to be shudderable within the sleeve 1 at its end. The tension elements 10 are fastened with their other or proximal ends to a stop tube piece 8 forming a stop. This stop tube piece is slidably mounted in the sleeve so as to be slidable on the sections of the expansion leg 6 lying in the sleeve 1. When displacing the loop 4 between the storage position and a first open position, this stop tube piece 8 slides inside the sleeve 1. For this purpose, it has a smaller diameter than the counter-stop tube piece 9 or as the tube hollow cross-section. The tension elements 10 extend outside of the ski opening 5 substantially parallel to the expansion legs 6. However, due to the kinks 18, the tension elements 10 are slightly spaced apart from one another to the expansion legs 6.

If the sling 4 is displaced from the storage position shown in FIG. 1a into the first open position shown in FIG. 2a, the expansion legs 6 spread apart from each other in a V-shaped manner as a result of their spring bias. In this position, the stop pipe piece 8 abuts against the counter-stop pipe piece 9 forming a counterstop from behind.

By applying a further push by means of the train-push piece 17 on the train-pushing element 2, the expansion legs 6 are slightly further displaced out of the sleeve 1 out. Since the tension elements 10 according to the against The counter stop 9 stepped stop 8 can not move further out of the sleeve 1, this leads to a deflection of the expansion leg 6, which causes the kinks 18 continue to move away from the tension members 10 and move towards each other, as shown in the figure 3a is shown. In this case, the free ends 6 'move away from each other, and the loop 4 spreads further on. If the kinks 18 collide against each other, this spreading is even amplified.

If the loop 4 is pressed perpendicularly against a base, the loop bend 7 bends, as shown in FIG. There it is

Loop bow 7 substantially at right angles to a plane 5 ', which is spanned by the V-shaped expansion legs 6, bent at right angles. This is a consequence of the greater bending stiffness of the expansion limbs 6, in particular in the direction transverse to the ski opening 5 or plane 5 ', which is a consequence of the orientation of the slim leaf springs of which the expansion limbs 6 are formed. For clarification, in FIG. 6, the three mutually perpendicular spatial directions are denoted by X, Y, Z. The sleeve 1 extends there parallel to the Z-direction. The loop vertex bow 7 is bent in a plane corresponding to the XY plane. As can be seen from FIG. 6, the loop 4 bends in the region of the bulges 19, that is to say in a region which is immediately adjacent to the free ends 6 'of the expansion limbs 6. This is the area with the largest opening width of the loop 4, which can be placed over the polyp or the like when using the device as a surgical cutting device. If the sling 4 is placed over a polyp, then a pull is exerted on the pull-push piece 17, so that the sling 4 contracts to encompass the polyp especially at its neck. Then, in the known manner, the separation of the polyp by the current introduced via the electrode 14. In order to be able to better hold the separated polyp in the loop 4, thickenings 12 in the region of the one-sided loop vertex arch 7 are provided in the second embodiment shown in FIG. In the embodiment shown in Figure 8 unilaterally loop inwardly directed hooks 13 are provided, which serve to hold the separated polyp in the loop 4.

The cross-sectional shape of the expansion leg 6 is chosen so that they bend more easily within the plane 5 'of the loop opening 5 as in the transverse direction thereto. For this purpose, the expansion legs 6 preferably have a rectangular cross-section, wherein the rectangular edges, which form the broad side surfaces of the expansion leg 6, are many times longer than the narrow edges standing at right angles thereto, which lie in the plane of the loop opening 5. Not only in the storage position, but also in the position of use, the broad side surfaces of the expansion leg 6 towards each other. They are in the storage position at least partially in touching contact.

In the above-described embodiments of the instrument 20, the pull / push element 2, the expansion leg 6, the loop bend 7 and the tension elements 10 are each made of metal. At the ends 6 'there is a firm and electrically conductive connection between the respective expansion leg 6 and the subsequent loop loop 7, as well as to the tension element 10. Likewise, the fixed connection shown in Figures 4, 5 between the two expansion legs 6 and Pull / push element 2 formed electrically conductive. The pull / push element 2 in turn is in electrically conductive connection to the electrical contact 14. Thus, the loop bow 7 is in electrically conductive connection with the contact 14, to which an RF generator, which is not shown in the drawings, to Current supply can be connected. In the exemplary embodiment of the instrument 20 according to FIGS. 1 to 6, it is provided that a so-called first longitudinal section 21 of the loop loop 7 has an electrically insulating jacket 23 which completely encloses the cross-section of the loop loop 7 on the circumference (see FIG. In this case, this longitudinal part section 21 extends approximately from the end 6 'of the adjacent expansion limb 6 to the apex 11 which is located at the distal tip of the sling 4. The loop loop 7 is thus isolated at one of two longitudinal sides of the loop 4. On the opposite side of the longitudinal center line denoted by M extends from the apex 11, a so-called second longitudinal section 22 of loop loop 7 to the end 6 'of the arranged on this side of the center line M Spreizschenkels 6. This second longitudinal section 22 has no electrically insulating Sheath and thus also has an exposed, electrically conductive surface. Although both longitudinal sections 21, 22 are electrically conductively connected to the contact 14, due to the insulating jacket 23 on the loop loop 7, only the second longitudinal section 22 acts as a cutting active electrode. Due to the jacket 23, no potential gradient to the adjacent tissue forms in the first longitudinal part section 21, so that there is no effective cutting region. Nevertheless, in the example, the two longitudinal sections 21 and 22 formed from only one piece of continuous metal wire, ie, the second longitudinal section has an electrically conductive core, so that the first length portion 21 by means of both expansion legs 6 electrically connected to the pull / push element 2 is. Alternatively, it would also be conceivable to produce the loop bow 7 in the region of the first longitudinal section section 21 of an electrically non-conductive material.

In the exemplary embodiment described with reference to FIGS. 1 to 6, the insulating sheath 23 terminates at the distal tip 24. According to FIG. 11, alternatively, there is the possibility that the electrically insulating sheath 23 until just above the apex 11 and the distal tip 24 extends to the respect to the center line M opposite side of the loop 4. Another alternative, which is not represented graphically, may be that the electrically insulating sheath 23 on the isolated loop side does not extend all the way to the apex 11, so that the distal tip 24 itself can still be effective cutting. FIG. 12 shows, as a still further alternative, that the loop bow 7 can be formed from two initially separate loop blade sections 7 ', 7 "whose free ends are each firmly embedded in a common tip body 25 made of an electrically insulating material, to which the sheath 23 extends.

With reference to Figures 9 and 10 is schematically simplified simplified shown that an electrically insulating sheath 23 is designed as a coating of aluminum carbonate, wherein in each case the coating pointing to the center of the loop 4 (see., The cutting direction of Figure 9 in FIG 3a) has circumferential areas of the loop loop 7 along approximately half the cross-sectional area of a roughening in the form of many individual peaks 26. At the remaining half of the circumference facing away from the loop opening 5, the coating or casing 23 has a smooth surface. The roughening allows a secure embrace of the tissue, while the smooth outer side facilitates the extension and retraction of the loop in / out of the sleeve 1. The difference between the variants shown in FIGS. 9, 10 is that in FIG. 9 the loop loop 7 has a monofilament loop wire wire, while the loop edge section in FIG. 10 has been formed from a plurality of comparatively smaller, respectively monofilament wires by means of twisting ,

In the alternative exemplary embodiment of an instrument 20 shown in FIGS. 13a, 13b, it is provided that also the expansion element 6 adjoining the first longitudinal section 21 of the loop loop 7 partially comprises an electrically insulating jacket 23 (for the sake of simplification uniformly using the reference numeral 23) extending from the end 6 'beyond the kink 18 to an end still in the forward position of the sleeve 1 in the position of use shown. This electrically insulated encased longitudinal part region of the expansion limb is designated by the reference symbol 27 in FIG. 13a. In the example shown, arranged on the opposite side of the center line M second expansion leg 6, which is also made of a flat metal strip, no electrically insulating sheath. This means that, in FIG. 13a, the second longitudinal section section 22 of the loop loop 7 located above the center line M together with the expansion leg 6 adjoining it form an electrode suitable for cutting, extending as a whole from the distal tip 24 of the loop 4 to its end proximal end extends in the region of the kinks 18, while the opposite half of the loop has an electrically continuous insulating coating 23 along this longitudinal section. In the example in FIG. 13 a, the tension element 10 located on the insulated loop side also has a corresponding casing 23.

Notwithstanding, it is provided in the exemplary embodiment shown in FIGS. 14a, 14b that both expansion limbs 6 and both tension elements 10 each have an electrically insulating sheath 23 in a longitudinal part section adjoining the loop loop 7. In the exemplary embodiment shown in FIG. 14a, only the so-called second longitudinal part section 22 of the loop loop 7 is therefore designed as a cutting electrode because of its electrically conductive surface. wherein its length portion at the loop circumference in the example is about one quarter. In FIGS. 1-14, the electrically insulating sheath 23 or coating for illustration is illustrated with exaggeratedly large thickness. It is understood that the Thickness of the sheath is to be chosen so that the loop can be easily moved forward and backward also by the counter piece 9 forming piece of pipe. The further exemplary embodiment of the instrument 20 according to the invention shown in FIGS. 15a, 15b differs from the exemplary embodiment in FIGS. 3a, 3b in that the first longitudinal section 21 of the loop loop 7 does not extend over the entire side thereof, ie not over half of its length. Instead, it is provided that, starting from the distal tip 24 in the proximal direction, a third longitudinal section 28 of the loop loop 7 extends over the approximately L-designated length, the third longitudinal section 28 is electrically conductive and has no electrically insulating sheath. Only starting from or adjacent to this third longitudinal section 28 does the so-called first longitudinal section 21, which carries the electrically insulating jacket 23, extend to the proximally adjoining expansion leg 6. In this exemplary embodiment, the loop 4 extends on the opposite longitudinal side the so-called second longitudinal part section 22 extends continuously from the distal tip 24 as far as the expansion leg 6 arranged on this other longitudinal side, that is, positionally adjacent thereto.

Figures 16a, 16b show yet another preferred embodiment. With regard to the first and third longitudinal section sections 21, 28, this corresponds to the embodiment according to FIGS. 15a, 15b. However, deviating from this, it is provided that the second longitudinal section 22 of the loop loop 7 extends from the distal tip 24 of the loop loop 7 only to a so-called fourth longitudinal section 29 of the loop loop 7 arranged on the same longitudinal side of the loop 4, the fourth longitudinal section 29 of the loop loop 7 has an electrically insulating Ummante- ment 23 and / or consists of electrically insulating material and in turn adjoins the expansion leg 6 lying on the same longitudinal side. In this respect, with respect to the center line M, a center-symmetrical configuration is selected in which on both longitudinal sides of the loop 4 in the region of the loop loop 7 only a limited front, adjoining the distal tip 24 and enclosing this longitudinal part section 22, 28 is cutting effect, while there on both longitudinal sides of the loop 4 in the proximal direction in each case an electrically insulating coated longitudinal section 23, 29 of the loop loop 7 connects. By way of example, ie not necessary, it is provided that the second longitudinal section 22 and the third longitudinal section 28 have the same length L. In the selected exemplary embodiment, the length L is approximately one quarter of the part length of the loop loop 7 attributable to one longitudinal side of the loop 4.

All disclosed features are essential to the invention. The disclosure content of the associated / attached priority documents (copy of the prior application) is hereby also incorporated in full in the disclosure of the application, also for the purpose of including features of these documents in claims of the present application. The subclaims characterize in their optional sibling version independent inventive development of the prior art, in particular to make on the basis of these claims divisional applications.

Claims

A surgical instrument (20), in particular high-frequency surgical polypectomy snare, in particular for the removal of pathological tissue in hollow organs, with a in a sleeve (1) guided pull / push element (2) for transmitting a tensile / thrust force from one to the one end of the sleeve (1) arranged actuating means (3) on a arranged at the other end of the sleeve loop (4) to the loop (4) from a storage position in which the loop (4) in an extended position in the sleeve ( 1) rests, in a use position in which the spread-open (5) of the loop (4) in front of the sleeve (1) is located, and back to relocate, the loop (4) two in the position of use partially in and before the Sleeve (1) lying, jointly V-shaped spread expansion leg (6), which are at least in one direction transverse to the opening plane (5 ¹ ) more rigid than the respective free ends (6 ¹ ) of the expansion leg miteina connecting loop (7), and wherein the pull / push element (2) is electrically conductive, characterized in that at least a first length portion (21) of the loop loop (7), which in the storage position on the one longitudinal side of the loop ( 4), an electrically insulating sheath (23) or consists of electrically insulating material and that at least a second length portion (22) of the loop loop (7), which is in the storage position on the other longitudinal side of the loop (4) electrically is conductive, has no electrically insulating sheath and by means of at least one expansion limb (6) is electrically conductively connected to the pull / push element (2).

2. Surgical instrument (20), in particular high-frequency surgical polypectomy snare, with a pulling device guided in a sleeve (1). Thrust element (2) for transmitting a pulling / pushing force from an actuating device (3) arranged at one end of the sleeve (1) to a loop (4) arranged at the other end of the sleeve (1) to move the loop (4 ) from a storage position, in which the loop (4) in an extended position in the sleeve (1) rests, in a position of use, in which the spread-open (5) of the loop (4) in front of the sleeve (1) is, and again back to relocate, wherein a displaceable together with the loop (4), slidably mounted in the sleeve (1) stop (8) when moving the loop (4) from its storage position in its position of use against a sleeve-fixed counter-stop (9) occurs to exerting a spreading action on the loop (4), wherein the loop forms two in the use position partially in and before the sleeve (1) lying V-shaped spread legs (6) whose free ends (6 ¹ ) with a loop loop (7) are connected, wobe i at each of the free ends (6 ') additional, substantially parallel to the expansion legs (6) extending tension elements (10) engage, which are connected to the opposite the expansion legs (6) slidable stop (8), and wherein the train - / push element (2) is electrically conductive, characterized in that at least a first length portion (21) of the loop loop (7), which is in the storage position on the one longitudinal side of the loop (4), an electrically insulating sheath (23) or consists of electrically insulating material and that at least a second length portion (22) of the loop loop (7), which is in the Verwahrstellung on the other longitudinal side of the loop (4) is electrically conductive, has no electrically insulating sheath and by means of at least a Spreizschenkels (6) is electrically conductively connected to the pull / push element (2). Instrument (20) according to claim 1 or in particular according thereto, characterized in that at each free end (6 ') of the expansion leg (6) additional, substantially parallel to the expansion limbs (6) extending tension elements (10) engage, which with a displaceable together with the loop (4), slidably in the sleeve (1) and relative to the expansion legs (6) slidable stop (8) are connected, which stop (8) during displacement of the loop (4) from its Verwahrstellung in its position of use against a sleeve-fixed counter-stop (9) occurs to exert a spreading action on the loop (4).

Instrument (20) according to claim 2 or in particular according thereto, characterized in that the V-shaped spread expansion limbs (6) are more rigid than the loop loop (7) at least in the direction transverse to the opening plane (5 ¹ ) spanned by the expansion limbs (6). ,

Instrument (20) according to one or both of claims 1, 2 or in particular according thereto, characterized in that the first longitudinal section (21), which is in the storage position on the one longitudinal side of the loop (4), in position on the local expansion leg (6) connects, and that the second longitudinal section (22), which is located in the storage position on the other longitudinal side of the loop (4), positionally connected to the local expansion leg (6).

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the first length portion (21) and the second length portion (22) each have half the length or each about half the length of the loop loop (7) and / / or each starting from a distal tip (24) of the loop loop (7), in particular to each extend to one of the expansion leg (6).

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the distal tip (24) of the loop loop (7) has an electrically insulating Ummante- ment (23) or consists of electrically insulating material or that the distal Tip (24) of the loop loop (7) is electrically conductive and has no electrically insulating sheath.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the spreading element (6) adjoining the first longitudinal section section (21) of the loop loop (7) is at least partially, in particular in a first longitudinal section section (21 ) adjacent longitudinal portion (27), or in total an electrically insulating sheath (23) or consists of electrically insulating material and that the other expansion element (6) is electrically conductive and has no electrically insulating sheath.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that both spreading elements (6) at least partially, in particular in a respective on the loop bend (7) adjacent longitudinal part section (27), an electrically insulating sheath (23) exhibit.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that both tension elements (10) at least partially, in particular in a respective at the associated expansion limb (6) adjacent Längenteilab- have cut (27), or a total of an electrically insulating sheath (23) or consist of electrically insulating material.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the electrically insulating sheath (23) is formed as a coating which comprises aluminum carbonate or consists of aluminum carbonate.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the electrically insulating coating is roughened at the middle of the loop oriented peripheral portions of the loop loop (7) and / or the expansion leg (6) and away from the loop center oriented peripheral regions of the loop loop (7) and / or the expansion limb (6) to run comparatively smooth.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the loop loop (7) has a monofilament, in particular elastically flexible, loop wire wire, in particular with a diameter in the range of 0.3 to 0.5 mm or that the loop loop (7) has a loop core in the range of 0.3 to 0.5 mm, comprising a plurality, in particular 10 to 20, monofilaments twisted together.

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the expansion legs (6) are formed by resilient flat strips which lie in the storage position with their broad side surfaces together. Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the loop bow (7) in the region of its tip (24) forms a bay (11) from acute angle or parallel to each other Schlingenbogenab- sections (II ¹ ) ,

Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the first length portion (21) of the loop loop (7) to a third length portion (28) of the loop loop (7) on the same longitudinal side of the loop (4 ) that the third length portion (28) extends from the distal tip (24) of the loop loop (7) to the first length portion (21) and that the third length portion (28) is electrically conductive, has no electrically insulating sheath, and by means of at least one expansion limb (6) is electrically conductively connected to the pull / push element (2).

17. Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the second longitudinal section (22) of the loop loop (7) from the distal

Point (24) of the loop loop (7), starting up to the on the same longitudinal side of the loop (4) arranged Spreizschenkel (6). 18. Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the second longitudinal part section (22) of the loop loop (7) from the distal tip (24) of the loop loop (7) starting up to one on extends along the same longitudinal side of the loop (4) arranged fourth Längenteilab- section (29) of the loop loop (7), wherein the fourth length Part portion (29) of the loop loop (7) has an electrically insulating sheath (23) or consists of electrically insulating material.

19. instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the second longitudinal section (22) of the loop loop (7) and the third longitudinal section (28) of the loop loop (7) have the same length (L) exhibit.

20. Instrument (20) according to one or more of the preceding claims or in particular according thereto, characterized in that the length (L) of the second longitudinal section (22) of the loop loop (7) and / or the length (L) of the third longitudinal section (28 ) of the loop loop (7) is about 20 to 30 percent, in particular about 25 percent, of the length of the loop loop (7) in a region on a longitudinal side from the distal tip (24) to a spreader leg (6).