MEDICAL NET SLING INSTRUMENT

Description

[0001] The invention relates to a medical retrieval net loop instrument according to the preamble of claims 1, 2 or 3. Such instruments are used in particular in medical endoscopy technology, e.g. as a polypectomy loop instrument in endoscopic polypectomy.

[0002] It is known for medical retrieval net sling instruments with a retrieval net held on a distal sling to essentially thread the retrieval net onto the distal sling, i.e., corresponding sections of the net fabric are loosely wound around the sling. To reduce displacement of the retrieval net along the sling, retaining loops of an additional retaining thread can be provided, which enclose the sling and an adjacent piece of the retrieval net fabric at the relevant connection point. German patent application WO 2008 / 154406 A1 discloses such a conventional retrieval net sling instrument. Another conventional retrieval net sling instrument of this type is disclosed in patent application EP 0 583 964 B1 for the containment of a shaped internal organ or tissue during endoscopic surgery in a bioabsorbable surgical bag.There, the net is formed by the bag, which has a hem around its circumference through which the sling is threaded. These conventional net-sling instruments are relatively complex to manufacture, and in use, undesirable shifting of the net along the sling can occur.

[0003] Medical retraction net instruments of the type mentioned above prevent such retraction net displacement along the loop by holding the retraction net with a net-holding section inside the loop's cross-section. European patent application EP 2 085 045 A1 discloses such a retraction net instrument in which the loop consists of a single, longitudinally slotted loop section designed as an electrosurgical electrode, and the retraction net is made of a shrinkable material and inserted into the longitudinal slot of the loop, where it is longitudinally movable but secured against being pulled out of the slot.

[0004] The patent application EP 1 967 146 A2 discloses an endoscopic combination instrument for cutting and capturing body tissue, wherein a capturing part of the instrument includes a one-piece loop of rectangular cross-section, to which a capturing bag, a cutting bag and a wire retaining strip are successively attached radially inwards, the wire retaining strip forming a receiving space for cutting wires with the cutting bag.

[0005] Other conventional medical retrieval net loop instruments are disclosed in Publication US 2016 / 0081702 A1 and Patents US 5,486,182 and US 5,735,298.

[0006] The invention is based on the technical problem of providing a net-snare instrument of the type mentioned above, which avoids or at least reduces the difficulties of the prior art mentioned above and which can be manufactured with relatively little effort and in which the net is held comparatively securely on the snare.

[0007] The invention solves this problem by providing a net-snare instrument with the features of claim 1, 2 or 3. Advantageous embodiments of the invention are specified in the dependent claims.

[0008] In the catching net loop device according to the invention, the catching net is held by the loop with its net-holding section inside the loop's cross-section. This easily prevents the catching net from shifting along the loop, and this retention of the catching net on the loop can be implemented with relatively little manufacturing effort. Additional retaining loops for attaching the catching net to the loop and / or for preventing unwanted shifting movements of the catching net along the loop are not required. The loop can be held completely or at least largely free of the catching net at its surface, and in particular at its radially outer and / or radially inner edge, and consequently has a smooth profile there, without this smooth profile being disturbed by catching net parts or retaining elements, such as retaining loops, etc.

[0009] According to one aspect of the invention, the loop comprises at least two conformal loop parts, i.e., the loop parts have a matching loop shape. The conformal loop parts lie against each other and are connected in this abutting position to form the loop, leaving a net-receiving gap between them. The safety net with its net-holding section is held in this net-receiving gap. The loop parts can, for example, be prefabricated separately and then attached to each other. The loop parts can be made of the same or different materials, e.g., all of metal or all of plastic, or at least one of metal and at least one of plastic. Any materials known per se for this purpose, including superelastic materials, can be used as metal or plastic materials for the loop.

[0010] According to a specific sub-aspect of the invention, at least a first and a second loop section are fixed to one another by means of at least one adhesive connection on the side facing away from the safety net and / or at least one clamping connection. This advantageously provides connections between the loop sections for their mutual fixation, which can be implemented as needed and depending on the application. Optionally, the safety net can also be included in the fixing of the loop sections to one another. In this case, the safety net is clamped between at least two of the loop sections and / or glued and / or welded / soldered to at least one of the loop sections and thus held in the net receiving slot. Alternatively, the safety net is held in the net receiving slot by a connection independent of the fixing of the loop sections to one another.

[0011] According to a further specific sub-aspect of the invention, a first loop part has a U-shaped cross-section, and a second loop part has a rectangular cross-section and is encompassed by the first loop part in a U-shape on three sides.

[0012] In one embodiment of the invention, fixing at least the first and second loop parts to one another involves the use of at least one welded / soldered joint or a clamp that clamps around at least these two loop parts, either along the entire length of the loop or at least sectionally at one or more spaced-apart points along the loop. This type of fixing can offer manufacturing advantages and optionally also serve to hold the safety net firmly clamped in the net receiving slot.

[0013] According to a further specific sub-aspect of the invention, the loop comprises an outer and an inner loop part of the same cross-section, wherein the outer loop part surrounds the inner loop part and faces an outer circumference of the inner loop part with its inner circumference. In other words, the inner loop part has a slightly smaller diameter or loop width than the outer loop part and is coaxially surrounded by it. The inner and outer loop parts thus lie coaxially in the same loop plane. The net receiving slot can be formed between them, into which the safety net can be inserted or passed, for example, in an axial direction, i.e., perpendicular to the loop plane.

[0014] According to a further aspect of the invention, the sling is manufactured in one piece, with the net-holding section of the safety net embedded within the interior of the sling's cross-section. For this purpose, the sling is manufactured as a cast component made of metal and / or plastic, into which the safety net with its net-holding section is cast, specifically as a single-component injection-molded plastic part or as a multi-component injection-molded plastic part with at least one first sling component made of metal or plastic and a second sling component, preferably made of plastic, cast onto it, wherein the safety net with its net-holding section is held between the sling components. This implementation of the safety net sling device according to the invention also ensures secure retention of the safety net in combination with a functionally advantageous sling design at a relatively low manufacturing cost.

[0015] In a further development of the invention, the safety net is held to the loop by means of at least one welded / soldered connection. This represents an advantageous method of connecting the safety net to the loop, whereby, in the case of a multi-part loop, it can be connected to only one, several, or all loop parts, depending on requirements and application.

[0016] In a further development of the invention, the catch net is formed by a mesh bag which is held to the loop by a bag edge; that is, the bag edge in this case forms the net-holding section of the catch net. This catch net design is advantageous for corresponding applications, and the attachment of the catch net to the loop is achieved simply by holding the bag edge inside the loop cross-section.

[0017] According to a further aspect of the invention, the safety net is formed from a circumferentially closed, folded piece of mesh fabric tubing that extends circumferentially through the interior of the loop's cross-section. In this case, the safety net is therefore double-walled due to the folding of the mesh fabric tubing. In the case of a multi-part loop, a first loop section can be inserted into the mesh fabric tubing, and a second loop section can be placed around the outside of the mesh fabric tubing. In the case of a one-piece loop, the mesh fabric tubing can be embedded in the loop's cross-section with a circumferential section serving as a net retention element. Using the mesh fabric tubing to form the safety net allows for advantageously simple fixation of the safety net to the loop by partially casting it in place.This is achieved by placing at least the first loop section inside the hose section and at least the second loop section around the outside of the hose section. Since the hose section is closed around its circumference, there are no free fabric ends on the perimeter of the net that would need to be held by the loop. Instead, the net, as a folded hose section, simply extends through the cross-section of the loop and is held or fixed in this position by the loop. This design variant can thus provide the net in a completely closed fabric form without free fabric ends around its circumference; only at the ends are there free fabric ends if the hose section is not closed but open at the ends.

[0018] In one embodiment of the invention, at least one first loop section is connected to the net-holding section of the capture net and / or to at least one second loop section by means of an adhesive joint located exclusively on an upper side of the loop, with the capture net extending into the loop only on an opposite lower side. This represents a manufacturing-technically and functionally advantageous implementation of the capture net loop device. The adhesive joint can be continuous along the entire length of the loop or applied only in sections.

[0019] Advantageous embodiments of the invention are illustrated in the drawings and described below. These include: Fig. 1 a perspective view of a distal end region of a medical retrieval net loop instrument with a loop made of radially adjacent loop parts and with a bag-like retrieval net, Fig. 2 the view of Fig. 1 with the outer loop part partially broken off, Fig. 3 a top view of the distal instrument area of Fig. 1 , Fig. 4 a perspective view accordingly Fig. 1 with the front half of the loop / catch net broken off, Fig. 5 a schematic sectional view along a line VV in Fig. 4 , Fig. 6 a schematic sectional view along a line VI-VI in Fig. 3 For a variant with additional adhesive bonding, Fig. 7 shows the sectional view of Fig. 6 For a variant with an additional clamp, Fig. 8 shows the sectional view of Fig. 5 For a further variant with an additional clamp, Fig. 9 shows the sectional view of Fig. 5For a variant with loop sections of a different cross-section, Fig. 10 shows the sectional view of Fig. 5 For a variant with axially nested loop parts, Fig. 11 shows a perspective view of a distal end region of another catching net loop instrument in a prefabrication stage with a fabric tube piece open at the end as a catching net and with a loop consisting of outer and inner loop parts, Fig. 12 shows the view of Fig. 1 for the completed instrument of Fig. 11 , Fig. 13 the view of Fig. 2 for the completed instrument of Fig. 11 , Fig. 14 the view of Fig. 3 for the completed instrument of Fig. 11 , Fig. 15 the view of Fig. 4 for the completed instrument of Fig. 11 , Fig. 16 the sectional view of Fig. 6 for the completed instrument of Fig. 11 , Fig. 17 the sectional view of Fig. 5For a variant with a single-component, one-piece loop construction, Fig. 18 shows a view illustrating one step of a method for manufacturing the instrument. Fig. 17 , Fig. 19 the view of Fig. 18 To illustrate a further step of this process, Fig. 20 shows the sectional view of Fig. 5 For a variant with a two-component, one-piece loop construction, Fig. 21 shows the sectional view of Fig. 20 For a variant with a fabric hose section for the catch net, Fig. 22 is the sectional view of Fig. 20 For another variant with a fabric tube section for the catch net, Fig. 23 shows the sectional view of Fig. 20 for a variant with a loop arrangement rotated by 90° and Fig. 24 the sectional view of Fig. 5 for a variant with a fabric hose section for the net and a three-part loop.

[0020] The Figs. 1 to 24Figure 1 shows exemplary embodiments of the medical retrieval net loop instrument according to the invention in its distal region of interest here. The instrument has a distal loop 1 and a retrieval net 2 held on the loop 1. In the exemplary embodiment of the Figs. 1 to 5The loop 1 comprises at least two conformal loop parts, i.e., two, three, four, or more conformal loop parts, where, in the example shown, it comprises two loop parts in the form of a first, here outer, loop part 1a and a second, here inner, loop part 1b. The at least two conformal loop parts 1a, 1b are connected to each other, specifically radially adjacent to each other, leaving a net-receiving gap 3 between them. The safety net 2 is held in the net-receiving gap 3 by a net-retaining section 2b and is thus held by the loop 1 within the cross-section of the loop 1 by the net-retaining section 2b; i.e., the part of the safety net located in the net-receiving gap 3 forms the net-retaining section 2b. The loop parts 1a, 1b can each have, for example, an elongated oval or substantially rectangular cross-section, as can be seen from the Figs. 1 to 5As can be seen, the cross-section of the loop 1 is accordingly composed of the cross-sections of the loop parts 1a, 1b with the intermediate net receiving gap 3.

[0021] The instruments shown can be used, for example, as polypectomy loop instruments in endoscopic polypectomy techniques. For this purpose, the distal loop 1 can be retracted into a shaft-forming tube 4 or a shaft tube of the instrument in a manner known per se, whereby the loop 1 contracts or folds accordingly. For this purpose, the loop 1 is formed by a loop wire made of metal or plastic, which is guided axially through the shaft tube 4 in a manner also known per se and therefore not shown or discussed further here. At a proximal end region of the instrument, the loop wire and the tube 4 are coupled to a control unit, by means of which the user can move the loop wire axially relative to the tube 4. In this way, the user can adjust the loop wire, which in its initial state is completely contained within the tube 4.move the retracted loop 1 out of the tube 4, thereby moving the loop 1 from its folded state in the tube 4 into its . Figs. 1 to 4 The loop 1 expands into the unfolded state shown. Moving the loop 1 out of the tube 4 can be achieved by advancing the loop wire and / or by retracting the tube 4. The loop wire can be made, for example, of a superelastic or flexible metal or plastic material, as is known per se. The two loop parts 1a, 1b can be made of the same material or of different materials, depending on requirements; for example, two different plastic materials, two different metal materials, or one of a plastic material and the other of a metal material.

[0022] The first and second loop sections 1a, 1b are preferably fixed to one another by means of at least one clamping connection and / or at least one adhesive connection and / or at least one weld / solder connection. For example, this can be achieved by several adhesive or weld / solder connections spaced apart along the loop 1.

[0023] As from the Figs. 1 to 5As can be seen, the outer loop part 1a conformally surrounds the inner loop part 1b, i.e., with identical shape, and its inner circumference faces an outer circumference of the inner loop part 1b. Furthermore, the inner loop part 1b has a slightly smaller diameter or loop width than the outer loop part 1a and is coaxially surrounded by the outer loop part 1a. The inner and outer loop parts 1b, 1a are thus coaxial with respect to a loop vertical axis H, which is defined as the plane normal direction of a loop plane E spanned or defined by the loop 1 and is therefore shown in the top view of Fig. 3 The net 2 is perpendicular to the plane of the drawing. The net is inserted axially, i.e., in the direction of the vertical axis of the loop H, into the net receiving slot 3, as shown in the view from Fig. 5 from underneath.

[0024] The safety net 2 can, as exemplified in the embodiment of the Figs. 1 to 5The net 2 is formed by a mesh bag 2a, which is held in the net receiving gap 3 by its bag edge as a net holding section 2b. In particular, the net 2 can be held to the loop 1 by its bag edge by means of at least one clamping connection and / or at least one adhesive connection and / or at least one welded / soldered connection. For example, the net 2 can be clamped by its bag edge between the outer loop part 1a and the inner loop part 1b along the entire length of the loop 1 or the net receiving gap 3, or at least at several spaced clamping points along the loop 1. The clamping can be implemented in such a way that the net 2 is securely held to the loop 1 solely by this clamping action.Alternatively, the retrieval net 2 with its bag edge can be additionally fixed to the inner or outer loop parts 1b, 1a by one or more adhesive points and / or one or more welded / soldered points. Any free ends of the fabric used for the retrieval net 2 located at the bag edge can be received in the net receiving slot 3, so that they are not exposed or require other finishing, e.g., to form a hem. The net fabric of the retrieval net 2 can be made of any suitable plastic or metal material, in particular one of the materials known per se for retrieval nets of polypectomy snare instruments.

[0025] Fig. 6 illustrates one implementation variant of the one described in the Figs. 1 to 5 the embodiment shown, the only difference being on the in Fig. 6An adhesive material is applied to the upper side of the loop 1 to form one or more adhesive joints 5. This can be a continuous adhesive joint running along the length of the loop 1 or several adhesive joints applied at intervals along the loop 1. Depending on the material of the two loop parts 1a, 1b and the safety net 2, the adhesive joint 5 creates a fixed connection between the safety net 2 on the one hand and the first loop part 1a and / or the second loop part 1b on the other, or only between the two loop parts 1a, 1b. If the adhesive joint 5 fixes the two loop parts 1a, 1b together, any other form of fixation between the two loop parts 1a, 1b may be unnecessary.

[0026] Fig. 7 shows another variant of the instrument. Figs. 1 to 5This variant differs in that an additional clamp 6 is provided, which clamps the loop parts 1a, 1b together, at least in sections. Depending on requirements and application, the clamp 6 can extend continuously along the length of the loop 1 or comprise one or more individual clamp parts that are spaced apart and attached at different points along the length of the loop 1. In the example shown by Fig. 7 The clamp has an essentially U-shaped cross-section with slightly inwardly pointing free clamp ends 6a. The clamp 6 is in Fig. 7 The clamp 6a is placed on top of loop 1 and engages loop 1, or rather its two loop parts 1a and 1b, with its inwardly facing free clamp ends 6a. The clamp 6 leaves the net receiving gap 3 on the side in which Fig. 7lower side free, on which the capture net 2 with its bag edge or net holding section 2b is inserted into the net receiving slot 3.

[0027] The clamp 6 ensures a secure clamping and thus a secure fixation of the two loop parts 1a, 1b to each other. Simultaneously, the clamp 6 can provide a clamping effect to secure the net 2 with its bag edge in the net receiving slot 3 between the two loop parts 1a, 1b. This eliminates the need for other connecting / fixing devices to hold the two loop parts 1a, 1b together and / or to secure the net 2 in the net receiving slot 3.

[0028] Fig. 8 illustrates a modification of the execution variant of Fig. 7Regarding the clamp 6. In this modified embodiment, the U-shaped clamp 6 ends straight at its free ends, i.e., the inwardly pointing clamp ends 6a of the embodiment of are missing. Fig. 7 Accordingly, the loop parts 1a, 1b are held by the clamp 6 in the version of Fig. 8 not overruled. Nevertheless, even bracket 6 of Fig. 8 Depending on requirements and application, the clamp 6 provides sufficient clamping force to hold the two loop parts 1a, 1b together and / or to securely hold the safety net 2 in the net receiving gap 3 between the two loop parts 1a, 1b. If necessary, the clamp 6 can be supported by additional fixing means to fix the two loop parts 1a, 1b to each other and / or the safety net 2 to the first loop part 1a and / or to the second loop part 1b.

[0029] Fig. 9 shows a variant of the instrument. Figs. 1 to 5 with the sole difference that here the two loop parts 1a, 1b each have an approximately semi-oval cross-section with one substantially flat and one substantially curved side. The two loop parts 1a, 1b face each other with their flat sides to form the intervening net-receiving gap 3. This embodiment results in a more circular cross-section for the loop 1 formed by the two loop parts 1a, 1b, whereas the loop 1 in the embodiment of the Figs. 1 to 5 has a rather rectangular cross-section.

[0030] Fig. 10 As a further embodiment of the invention, a medical retrieval net loop instrument is shown as a variant of the instrument of Figs. 1 to 5with the difference that the loop 1 is formed from a first loop part 1c and a second loop part 1d, which do not both have the same, for example rectangular, cross-section, but only the second loop part 1d has an essentially rectangular cross-section, while the first loop part 1c has a U-shaped cross-section and the second loop part 1d accordingly surrounds or overlaps it in a U-shape on three sides.

[0031] In this embodiment, the net receiving gap 3 between the two loop sections 1c, 1d has a U-shaped cross-section. The capture net 2 is held in this U-shaped net receiving gap 3 by virtue of its free, open bag edge being inserted into the net receiving gap 3 as the net holding section 2b of the bag 2a that forms the capture net 2. The bag edge lies within the net receiving gap 3 along its entire length, thus being held between the two loop sections 1c, 1d on three sides. Given the clamping force between the two loop sections 1c, 1d, this provides a very high holding force for the capture net 2 on the loop 1. If necessary, this can be further enhanced by a clamp-like design of the first loop section 1c, in which case its two U-shaped sides are clamped onto the second loop section 1d.First, the mesh bag 2a of the capture net 2 is placed around the second loop section 1d in a U-shape with its bag edge, so that it is held firmly in the net receiving slot 3 when the first loop section 1c is placed on top. Depending on requirements and application, further fixing means for securing the capture net 2 to the loop 1 or the two loop sections 1c, 1d to each other may be omitted or additionally provided.

[0032] The Figs. 11 to 16 Figure 1 shows a further embodiment of a medical retrieval net loop instrument according to the invention, wherein the retrieval net 2 is formed by a folded mesh fabric tube section 2c. In the example shown, the tube section 2c is closed on its circumference and prefabricated or prepared open at both ends, as shown in Figure 2. Fig. 11 to recognize. For the instrument of the Figs. 11 to 16 Otherwise, the same components can be used as for the above embodiment of the Figs. 1 to 5or for the above embodiment of Fig. 10 can be used, so reference can also be made to its description above. This applies in particular to the formation of loop 1 from the first loop part 1a or 1c and the second loop part 1b or 1d.

[0033] To produce the finished loop 1 with the safety net 2, in this embodiment, if, for example, the loop parts 1a and 1b of the exemplary embodiment of the Figs. 1 to 5 The second, inner loop part 1b is inserted into the interior of the mesh fabric tube piece 2c, as shown. Fig. 11 This is evident from one of the two open ends of the tube section 2c. The tube section 2c is then folded accordingly and placed against the second loop section 1b, and pressed through it from one side to form the desired mesh pocket. Subsequently, as also described in Fig. 11As illustrated, the first, outer loop part 1a is placed on or around the inner loop part 1b until the outer loop part 1a assumes its coaxial position surrounding the inner loop part 1b, as shown in the Figs. 12 to 16 This can be seen. Before or after attaching the outer loop part 1a, the mesh fabric tube piece 2c placed against the inner loop part 1b can be closed at its open ends if necessary.

[0034] The Figs. 12 to 16 illustrate the instrument completed in this way in its distal region of interest here, according to the Figs. 1 to 5 As can be seen from the Figs. 12 to 16 As can be seen, the use of the mesh fabric tube piece 2c creates the catch net 2 in a double-walled pocket or bag shape with a [missing information] in the Figs. 12 to 16upper mesh layer 2d and lower mesh layer 2e. Since the capture net 2 surrounds the inner loop part 1b in a circumferentially closed form, as is particularly evident from Fig. 16 As can be seen, in this embodiment the net 2 is held solely by the inner loop part 1b. The outer loop part 1a, which lies coaxially against the inner loop part 1b from the outside, fixes the net 2 firmly in this position by forming the intervening net receiving gap 3 with the inner loop part 1b, in which the net 2 with its net holding section 2b is held.

[0035] Regarding possible fixations of the two loop parts 1a, 1b to each other, as well as optionally of the safety net 2 to one or both loop parts 1a, 1b, the following applies to the instrument of Figs. 11 to 16 The same implementation options are possible as above for the instruments of the Figs. 1 to 10explains what can be referred to. The instrument of Figs. 11 to 16 As explained, it can be manufactured relatively easily and allows the provision of the safety net 2 in a double-walled design and very secure attachment to the loop 1 without any further additional effort. Alternatively to the embodiments of the Figs. 1 to 16 with two-part or multi-part loop construction, the Figs. 17 to 22 Exemplary embodiments of a single- or multi-component, one-piece loop construction.

[0036] In the exemplary embodiment of Fig. 17The loop 1 is manufactured as a single-component injection-molded plastic part, in whose cross-section the safety net 2 with its net-holding section 2b is cast. In this case, the loop 1 consists of two loop halves 1e, 1f opposite each other with respect to the cast-in safety net 2, wherein, for example, loop half 1e corresponds to the outer loop part 1a and loop half 1f to the inner loop part 1b of the exemplary embodiment of the Figs. 1 to 5 This can correspond to the following. The catch net 2 can, for example, be bag- or pocket-shaped, similar to the mesh bag 2a of the embodiment shown in the Figs. 1 to 5 The net 2 is securely held on the loop 1 without further fixing measures by pouring its net holding section 2b or bag edge into the interior of the oval cross-section of the loop 1 shown here, for example.

[0037] This instrument variant can be manufactured using plastic injection molding technology, for example, by first inserting a catch net precursor 2f into an injection mold 7, which, in the usual manner, provides a mold cavity 7c by means of two casting halves 7a, 7b, as shown in Fig. 18 This is illustrated schematically. Then, as in Fig. 19 As schematically illustrated, the plastic material for the loop 1 is injected into the mold cavity 7c, thereby embedding the net-holding section 2b of the safety net 2 within the cross-section of the cast loop 1. After removing the cast loop 1 with the embedded safety net 2 from the mold 7, any protruding part of the safety net can be cut off, preferably flush with the surface of the single-component cast loop 1.

[0038] Fig. 20As a further embodiment of the invention, an instrument with a two-component, one-piece, cast loop assembly is shown. In this assembly, the loop 1 consists of a first loop component 1g and a second loop component 1h cast onto it, e.g., by plastic injection molding. In the example shown, the first loop component 1g has a rectangular cross-section, while the remaining cross-section is, as in the exemplary embodiment of Fig. 17 The oval loop 1 is formed in cross-section by the molded-on plastic material of the second loop component 1h. The catch net 2, with its net-holding section 2b, is located approximately in the center of the cross-section of the loop 1, partly between the two loop components 1g and 1h, and partly inside the second loop component 1h, which is molded on both sides. As in the exemplary embodiment of Fig. 17Here too, one cross-sectional side of the loop 1 can be located on one or the other side of the net 2 or its net holding section 2b, respectively, corresponding to the radially outer loop part 1a or the radially inner loop part 1b of the embodiment. Figs. 1 to 5 The first loop component 1g can, for example, consist of a superelastic metal material, such as a nickel-titanium alloy. To manufacture the instrument, the first loop component 1g, together with the net-holding section 2b of the capture net 2, can be placed in a plastic injection mold according to mold 7 of [reference missing]. Fig. 18 are inserted, after which the plastic material for the second loop component is injected for 1 hour.

[0039] Fig. 21 shows a variant embodiment of the invention, which is similar to that of Fig. 20 The modification means that the starting material for the catch net 2 is not a net bag as in the example of the Figs. 1 to 5, but the hose section 2c according to the embodiment of the Figs. 11 to 16 is used. For manufacturing, in this case the hose section 2c with a circumferential section as the net holding section 2b can be placed in a plastic injection mold according to mold 7 of Fig. 18 can be inserted, for example together with the first loop component 1g. In an alternative version with a single-component, one-piece loop construction as in the exemplary embodiment of the Figs. 17 to 19 Only the hose section 2c is inserted into the casting mold cavity and overmolded with the material of the then single-component loop 1 in the net holding section 2b.

[0040] Fig. 22 shows a further embodiment variant as a modification of the exemplary embodiment of Fig. 21 In the version of Fig. 22With a two-component, one-piece loop construction, the loop consists of a loop core as the first loop component 1g and a covering as the second loop component 1h, made of a plastic material that completely surrounds the core-forming first loop component 1g in cross-section; that is, the material of the core-forming first loop component 1g is, in this case, encased in the material of the covering second loop component 1h. Between the two loop components 1g and 1h is the net retention section 2b of the catch net 2, which itself is formed in two layers with net layers 2d and 2e from the hose section 2c. In the example shown, the net retention section 2b completely encircles the core-forming loop component 1g, so that both net layers 2d and 2e are adjacent to each other and emerge from the loop 1 on the same side, as shown in the cross-sectional view of Fig. 22on the lower narrow side of the loop 1. In this embodiment, the loop 1 thus remains completely free of the catch net 2 on its circumference, except for the point where the catch net 2 exits the loop on its narrow side, and can therefore, for example, have a completely smooth surface profile corresponding to the cast shell-forming loop component 1h. The catch net 2 is held very securely to the loop 1 by the enclosing of the core-forming loop component 1g and the encasing of the shell-forming loop component 1h, without the need for any other fixing measures.

[0041] In the exemplary embodiments of the Figs. 1 to 20 The safety net is inserted into the loop perpendicular to the plane of the loop, e.g., on the underside of the loop. In alternative designs, such as the exemplary embodiment of the Fig. 23 As shown, the catch net 2 is inserted into loop 1 parallel to the loop plane. Fig. 23This is demonstrated using the example of a two-component loop design accordingly. Fig. 20 In alternative versions, the loop is analogous to the embodiments described in the Figs. 1 to 19 Designed in one or more parts. In these design variants with a safety net inserted parallel to the loop plane, the cross-section of loop 1, as in the case of Fig. 23 , preferably a greater length in the plane of the loop than in the plane perpendicular to it, in contrast, for example, to the variants according to the Figs. 17 and 20 .

[0042] Fig. 24 Figure 1 illustrates an embodiment of the invention with three conformal loop parts: a middle loop part 11, an outer loop part 1m, and an inner loop part 1n. The safety net 2 in this example is analogous to the embodiment of Figure 2. Fig. 22The net is formed in two layers with net layers 2d and 2e from the hose section 2c, wherein the net retaining section 2b encircles the middle loop section 1l, so that both net layers 2d and 2e are led out of the loop 1 on the same side, preferably on the underside of the loop, from which the net extends downwards from the plane of the loop. The net retaining section 2b is held on one side between the middle loop section 1l and the outer loop section 1m, and on the other side between the middle loop section 1l and the inner loop section 1n. The three loop sections 1l, 1m, 1n and the net retaining section 2b of the net 2 can be fixed in one of the ways described above for the other embodiments, e.g.by fixing all four parts to each other or by fixing the net holding section 2b to one, two or all three loop parts 1l, 1m, 1n and / or by fixing the three loop parts 1l, 1m, 1n in pairs or together.

[0043] As the illustrated embodiments explained above clearly demonstrate, the invention provides a medical retraction net sling device that is relatively easy to manufacture and offers very high functional reliability and dependability. In particular, the retraction net is held very securely and against unwanted displacement on the sling with relatively little effort.

[0044] It is understood that the invention includes further advantageous embodiments, for example, those in which the loop is constructed in one piece from three, four, or more conformal, adjacent loop parts or from three, four, or more loop components using a conventional metal or plastic casting technique, wherein the net-receiving gap is formed between at least two of these loop parts or loop components. In addition to the bag / pouch shape shown, any other net shapes known per se for this purpose can be used for the net.

Claims

1. Medical net-and-loop type retrieval instrument comprising - a distal loop (1) and - a retrieval net (2) that by way of a net holding portion (2b) is firmly held by the loop (1) in the interior of the cross section of the loop, characterized in that - the loop comprises at least two conforming loop parts (1a, 1c; 1b, 1d) which while leaving a net receptacle gap (3) therebetween are connected so as to bear on one another, and the retrieval net (2) by way of the net holding portion (2b) is firmly held in the net receptacle gap, wherein the at least two loop parts are fixed to one another by means of at least one adhesively bonded joint connection on the side opposite from the retrieval net and / or by means of at least one clamped joint connection and / or comprise an inner loop part (1b) and an outer loop part (1a) of equal cross-section which surrounds the inner loop part and faces with an inner periphery an outer periphery of the inner loop part, or wherein a first loop part (1c) comprises a U-shaped cross-section and a second loop part comprises a rectangular cross-section and the first loop part encompasses the second loop part in a U-shape on three sides.

2. Medical net-and-loop type retrieval instrument comprising - a distal loop (1) and - a retrieval net (2) that by way of a net holding portion (2b) is firmly held by the loop (1) in the interior of the cross section of the loop, characterized in that - the loop (1) is made integrally, while embedding the net holding portion (2b) of the retrieval net in the interior of the cross section of the loop, as a single-component casting or a multi-component casting having at least one first loop component from a first material from metal or plastics material, and a second loop component, molded to said first loop component, from a second material that is different from the first material, and the retrieval net at the net holding portion thereof is held so as to be cast in the casting.

3. Medical net-and-loop type retrieval instrument comprising - a distal loop (1) and - a retrieval net (2) that by way of a net holding portion (2b) is firmly held by the loop (1) in the interior of the cross section of the loop, characterized in that - the retrieval net (2) is formed by a folded-together woven-fabric net hose piece (2c) which is circumferentially closed and which in the circumferential direction extends through the interior of the cross section of the loop (1).

4. Medical net-and-loop type retrieval instrument as claimed in claim 1, further characterized in that at least a first and a second of the loop parts are fixed to one another by means of at least one welded / soldered joint connection.

5. Medical net-and-loop type retrieval instrument as claimed in claim 1 or 4, further characterized by a clip (6) which at least in portions encompasses at least the first and the second loop part so as to conjointly clamp them together.

6. Medical net-and-loop type retrieval instrument as claimed in any one of claims 1 and 3 to 5, further characterized in that the retrieval net is held on the loop by means of at least one clamped joint connection and / or at least one adhesively bonded joint connection and / or at least one welded / soldered joint connection.

7. Medical net-and-loop type retrieval instrument as claimed in any one of claims 1, 2, and 4 to 6, further characterized in that the retrieval net is formed by a woven-fabric net pouch (2a) which by way of a pouch periphery is firmly held on the loop.

8. Medical net-and-loop type retrieval instrument as claimed in any one of claims 1 and 4 to 7, further characterized in that at least a first one of the loop parts by means of an adhesively bonded joint connection is connected to the net holding portion of the retrieval net and / or to at least a second one of the loop parts, said adhesively bonded joint connection being situated exclusively on an upper side of the loop, wherein the retrieval net extends into the loop only on an opposite lower side.