Marking element for marking tissue

Abstract

To provide a marking element suitable for marking a body tissue.SOLUTION: A marking element has a shape that is at least approximately rotationally symmetrical with respect to the longitudinal axis, the marking element comprising interconnected preformed elastic metal braces and taking a radially compressed state and a radially expanded state. In the expanded state, the marking element is constricted at the central longitudinal section and expands continuously in the longitudinal direction from the central longitudinal section towards the two sides. The marking element has two widened longitudinal sections, the maximum outer diameter of which is 2 to 20 times larger than the outer diameter of the central longitudinal section in the expanded state of the marking element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a marking body provided for implantation into soft tissue (e.g., adipose tissue, muscle tissue, tumor tissue, breast tissue, liver tissue, lymph nodes, particularly axillary lymph nodes, etc.), the marking body having an elastic, compressible, and self-expanding support structure. The support structure is formed by an elastic, preformed web. The marking body has a shape that is approximately rotationally symmetric about at least a longitudinal axis. The present invention further relates to an implantation system and a method for implantation. [Background technology]

[0002] Implantable marking bodies for marking tissue sites are well known. In principle, such marking bodies are designed so that they can be implanted into the tissue region to be marked using a suitable device, either permanently or for a period of time (e.g., during two interventional events) so that they remain there. In this way, treatment-relevant tissue (e.g., tissue containing a tumor or other tissue abnormality, or otherwise healthy tissue intended to be potentially observed) can be marked for a relatively long period of time. The marking effect of these marking bodies is achieved as a result of their visibility during examination using imaging diagnostic methods, particularly in the case of methods based on X-ray radiation, nuclear magnetic resonance, or ultrasound.

[0003] WO 2006 / 000568 A2 (Patent Document 1) discloses a marker for marking a tissue site following insertion of the marker using an applicator or cannula with a known structure. The effect achieved here is that the marker remains at the tissue site to be marked for a relatively long period of time, thereby clearly marking the tissue site for subsequent diagnostic and therapeutic activities. The marker consists of one or more wires, which may be twisted in a central marker section and have different shapes at the two end sections of the marker.

[0004] Surgical instruments, in particular marker instruments for marking body tissue sections, are further described in EP 1 782 745 B1. In particular, the instrument should be suitable for marking tumor tissue prior to surgical removal of said tissue.

[0005] In the field of orthopedic surgery for treating osteonecrosis, US Pat. No. 8,112,869 B2 (Patent Document 2) discloses a manufacturing method for producing a spherical cage structure made of nitinol. The cage structure produced according to the described method is introduced in a compressed form through a channel drilled in the femur, expands within the femoral head, and the cavity is subsequently filled with solidifying bone graft, thereby providing stabilization of the femoral head. In this application field, the diameter of the cage structure ranges from 20 to 30 mm.

[0006] US9,216,069B2 describes a marker system for breast biopsy, in which a number of marker elements are preloaded in a compressed manner into an administration tube, the marker elements comprising at least one radiopaque wire segment.

[0007] Regarding breast biopsy, U.S. Pat. No. 8,060,183 B2 generally discloses a marker surrounding a cavity for marking in imaging procedures. In one variation, the marker consists of an outer hollow body closed at both elongated ends and a smaller permanent marker positioned within the outer body. The description goes on to explain that the outer hollow body is made of a bioresorbable material and degrades over a period of time, while the inner permanent marker remains in the tissue. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2006 / 000568 [Patent Document 2] U.S. Patent No. 8,112,869 [Patent Document 3] U.S. Patent No. 8,060,183 Summary of the Invention [Problem to be solved by the invention]

[0009] SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved marking body for implantation in tissue. [Means for solving the problem]

[0010] The marking body according to claim 1 is proposed to achieve this goal. Thus, the marking body has a shape that is approximately rotationally symmetrical at least about its longitudinal axis and is capable of adopting a radially compressed state and a radially expanded state. The marking body is formed by an elastic, preformed web, which provides an elastic, compressible, and self-expandable support structure. For example, the webs are interconnected by weaving or in any other manner. In its expanded state, the marking body is tightened at a central longitudinal section and expanded in the longitudinal direction from the central longitudinal section to both longitudinal ends, thereby having, for example, two flared longitudinal sections, each of which may have an approximately conical shape, with the tips of the cones touching. In the expanded state of the marking body, the maximum outer diameter of the flared longitudinal sections is 2 to 20 times larger than the outer diameter of the central longitudinal section. At least in the flared longitudinal section, the marking body is formed in the circumferential direction by 5 to 96 webs which, in their compressed state, extend substantially in the longitudinal direction of the marking body, cross in pairs at their longitudinal ends, and are interconnected in a cohesive and / or interlocking manner. By extending substantially in the longitudinal direction of the marking body, it is meant that, in the compressed state of the marking body, the webs extend at an angle of less than 10° relative to the longitudinal axis of the marking body.

[0011] Such marking bodies can advantageously meet two requirements: first, they provide good ultrasound visibility, and second, they resist migration, i.e., movement of the marking body within the tissue during and after implantation.

[0012] If a biopsy, e.g., a vacuum biopsy, is performed before marking, the tissue pressure acting against the direction of propagation of the marking body may therefore be lower or even non-existent due to pre-existing cavities. In such cases, expansion of the marking body after placement prevents the marking body from retracting into the biopsy cannula or being flushed through the puncture channel of the vacuum biopsy unit.

[0013] An embedding system comprising a marking body and an embedding device is proposed as a further aspect of the invention.

[0014] The present invention is based on the idea that the visibility of the marking body should be ensured even in the case of imaging methods based on different operating principles. Furthermore, the unique and clear visibility of the marking body should be ensured under the widest possible range of examination conditions and applications. In the case of ultrasound-based imaging methods, good recognition of the marking body occurs using the highest possible sound reflection of the support structure made of metal or hard plastic.

[0015] In ultrasound examinations involving medical ultrasound ranging from 1 MHz to 40 MHz in B-mode (intensity modulation), the support structure of the marking body causes the ultrasound waves incident on the structure to be circular in cross section, transverse to both longitudinal edges of the marking body. By matching the parameters of web diameter (or width and thickness), web number, web density, and web material, what is obtained is that only a portion of the acoustic energy is reflected by the structure, while the remaining portion of the energy is transmitted. As a result, a perfect circle appears as a representation in the ultrasound image. For other structures of this type, the ultrasound energy is primarily reflected from the first surface of the marker, resulting in a shadow in the image.

[0016] A further feature of the chosen marking body geometry is the consequence of the fact that, as incident ultrasound waves at both longitudinal ends of the marking body in the cross section, a cross can be identified in the ultrasound image instead of a circle. Both geometric shapes, i.e., a circle and a cross, do not occur in ultrasound images of biological tissue in this form and can therefore be particularly easily recognized and assigned to the marking body by researchers.

[0017] For X-ray based imaging methods, such as mammography, high absorption of X-ray radiation by the support structure also leads to good recognition ability in the X-ray image. High absorption of X-ray radiation by the support structure can be traced to metal within the support structure, such as metal wires or metal particles embedded in plastic.

[0018] In the case of magnetic resonance imaging (MRI), the magnetic properties of the marking body material lead to its good recognition ability.

[0019] Advantageous developments of the invention can be seen from the dependent claims, which define in detail advantageous options for realizing the concepts described above within the scope of the subject matter and in terms of further advantages.

[0020] In particular, a support structure for weaving, braiding, wrapping or knitting is provided, the advantage here consisting of the economical productivity of a structure that spreads over an area and is made into a hollow double cone shape within a subsequent production step, the cone tips of which meet in the center.

[0021] Alternatively, the support structure can be formed by a tube that is inserted lengthwise and compressed, causing sections separated from each other by slits to bulge outward. If the compressed state of such a support structure is its relaxed state, the support structure is self-expanding.

[0022] A further alternative for the support structure is a support structure made from plastic, for example a marking body made from PEEK, for example manufactured within the scope of an injection molding method.

[0023] The marking body's support structure is preferably self-expanding and designed to be resiliently compressible under a radial force of at least 1 Newton. When the marking body is implanted in tissue in a resiliently compressed state, the marking body independently transitions to its expanded state and remains so when tissue exerts a radial force of less than 1 Newton on the marker on the marking body.

[0024] For implantation purposes, the marking body is first brought to the desired location using a cannula and then pushed out of the cannula lumen so that it can expand into the tissue, with the expansion force with which the marking body, held in a compressed state within the cannula, expands immediately upon ejection from the cannula preferably being at least 1 Newton.

[0025] As an example, the marking body support structure can be designed to have an expansion force greater than 40 Newtons when the marking body is compressed to a maximum diameter of less than 1 mm, and still greater than 3 Newtons, e.g., 6 Newtons, when the marking body is at a maximum diameter of 1.5 mm. The marking body support structure can be designed such that the expansion force corresponds substantially to the minimum radial force that needs to be applied to elastically compress the marking body.

[0026] The energy stored in the support structure of the marking body can be adjusted by suitable selection of the web thickness of the support structure web or the number of support structure webs. The energy stored in the support structure of an elastically compressed marking body further depends on the material forming the support structure web of the marking body. Thus, in accordance with the present invention, it is possible to produce marking bodies in which a radial force of more than 1.5 Newtons, 2 Newtons, or even more than 3 Newtons must be applied to compress the marking body to a maximum diameter of less than 1.5 mm. Similarly, in accordance with the present invention, it is also possible to produce marking bodies in which a radial force of 0.5 Newtons is already sufficient to compress the marking body to a maximum diameter of less than 1.5 mm.

[0027] The support structure of the marking body is designed to be self-expanding, so that the marking body independently transitions to its expanded state as soon as the radial force drops below the level required to elastically compress the marking body. The support structure of the marking body is preferably formed by braided individual wires. Thus, the web of the marking body is preferably formed by 5 to 96 wires, for example, 18 to 48 wires, particularly 24 or 36 wires, each extending from one longitudinal end of the marking body to the other, crossing each other multiple times and thus forming a web-like support structure made of a braided wire mesh with multiple intersections. Marking bodies formed by 12 to 48, particularly 24, braided wires, preferably made of a titanium alloy, particularly Nitinol, are particularly preferred.

[0028] The webs of the marking bodies, i.e., for example, wires, are in this case interconnected, preferably in pairs, at their free longitudinal ends, in particular preferably welded, in particular twisted and welded, To this end, the free longitudinal ends are preferably each located on an intersection of the support structure, i.e., for example, at the places where wires in a braided wire mesh cross.

[0029] The webs of marking material may be cohesively interconnected at their intersections, in particular welded, although this is preferably not envisaged.

[0030] Alternatively, or in addition, the webs of marking material can be twisted relative to one another at the intersections.

[0031] In the expanded state of the marking body, its outer diameter preferably increases continuously in the longitudinal direction, starting from the central longitudinal section, to both longitudinal ends, so that the marking body has its maximum diameter at both longitudinal ends.

[0032] In an alternative embodiment variant, the outer diameter of the marking body, in its expanded state, first increases longitudinally, starting from the central longitudinal section, to both longitudinal ends, and then decreases again over the further course to the longitudinal ends, so that the marking body has its maximum diameter at a certain distance from their respective longitudinal ends.

[0033] In both cases, the marking body ideally has the same maximum diameter in the flared longitudinal section, however, in practice the two maximum diameters typically deviate slightly from each other, but the difference in the maximum diameters in the radially unloaded state of the marking body is preferably less than 10%.

[0034] In the expanded state, the marking body preferably flares out in the flared longitudinal sections, starting from the central longitudinal section, at an opening angle of 25° to 50°, in particular 30° to 45°, relative to the longitudinal axis of the marking body.

[0035] In the case of marking bodies formed from braided wire, the wire diameter is preferably less than 0.5 mm, preferably 0.1 mm or less, for example, 0.05 mm to 0.10 mm. A small wire diameter has a positive effect on the compressibility of the marking body, which is required in the case of implantation using a cannula with the smallest possible diameter. In contrast, a larger wire diameter has a positive effect on the setting force of the marking body's support structure. This leads to a marking body that is also able to expand against the tissue pressures commonly found in hard tissues, such as tumor tissue.

[0036] Furthermore, it is advantageous if the diameter of the marking body in the expanded state is less than 10 mm or less than 8 mm, preferably between 3.0 mm and 5.0 mm. Marking bodies within this diameter range represent a compromise between visibility in imaging methods on the one hand and the spatial requirements of foreign bodies in tissue on the other hand.

[0037] An extended marking body with a certain minimum size offers the advantage that it can be sensed by the surgeon during treatment.

[0038] Furthermore, the diameter of the marking body in the compressed state is preferably less than 3 mm, and more preferably less than 1.0 mm. The small diameter or high compressibility of the marking body in the elastically compressed state facilitates implantation of the marking body using a relatively narrow cannula, i.e., a cannula with a small diameter. The smaller diameter reduces the risk to the patient related to injury and pain, and puncture incisions and / or anesthetics can be omitted more frequently and within simplified handling. This further provides advantages in terms of application duration and cost.

[0039] Preferably, the support structure, eg its web and / or sleeve, is therefore roughened, eg by sandblasting, to increase ultrasound visibility.

[0040] The marking body web preferably consists of a titanium alloy, in particular Nitinol. Due to the material properties of Nitinol as a superelastic material, the marking body advantageously transitions from an elastically compressed state to an expanded state independently after being delivered from the implantation device, particularly in response to pressure exerted by tissue adjacent to the marking body acting in the expansion direction. The use of other superelastic materials and / or shape memory alloys is also possible.

[0041] As an example, rapid self-expansion of the marking body after implantation, such as facilitated by the use of nitinol, is particularly crucial to prevent migration of the marking body during and after implantation.

[0042] Furthermore, advantageously, a support structure material is provided that is not resorbable. This aspect of the invention leads to the advantage that the marking material, which remains in the tissue for a relatively long period of time, does not degrade. This also prevents the marking material from adversely interacting with adjacent tissue, particularly by releasing the contents or material components of the support structure into the adjacent tissue.

[0043] The wires of a multi-wire support structure need not all be made of the same material. Rather, individual wires made of different materials may be included within the braid to optimize visibility in magnetic resonance imaging or to increase x-ray visibility in computed tomography or under a C-arm. By way of example, suitable materials include titanium, gold, iron-containing alloys, and / or nitinol.

[0044] In particular, if the support structure of the marking body is formed by a braided wire mesh, the central longitudinal section can be provided with a sleeve that compresses the central longitudinal section to its smallest diameter, preferably so that all the webs are directly adjacent to each other laterally within the central longitudinal section. The sleeve has the additional effect of holding all the individual wires together in a crimping manner, for example, so that the connections of the individual wires at their longitudinal ends do not deteriorate and can be provided for redundancy reasons.

[0045] The sleeve is preferably a Nitinol sleeve. Instead of a Nitinol sleeve, it is also possible to use other clamps, for example sleeves made of different materials. Such clamps may also have different shapes. By way of example, the clamps may therefore differ from one another in terms of shape and length. This also allows the use of marking bodies with different clamps, so that the individual marking bodies can be individually identified following implantation.

[0046] Further distinguishing features of the individual marking bodies can be clamps made of different materials, for example, clamps that are more or less radiopaque, or clamps with different magnetic properties, especially for differentiation in images recorded by magnetic resonance imaging. Clamps with air / gas content can provide improved recognition capabilities in ultrasound images.

[0047] Furthermore, marking bodies are advantageously provided that complement or in addition to the support structure, including marker features, such as sleeves of different shapes and / or lengths, and in particular metallic or other radiopaque molded parts within the support structure. Among other advantages, this allows multiple different marking bodies simultaneously implanted within a patient to be clearly distinguished, or at least more easily distinguished, in imaging methods. By way of example, these molded parts can be rod- or sphere-shaped, positioned within or fastened to the support structure, and can further have different dimensions for improved differentiation. By way of example, these molded parts can be formed from metal.

[0048] Further aspects relate to embedding systems and embedding devices having marking bodies of the type claimed herein.

[0049] The implantation device is designed for implanting the marking body according to the present invention and, to this end, is equipped with a cannula. As a result, using the implantation device, the marking body can be advantageously placed at the tissue site to be marked by puncturing the skin layer and the underlying tissue, particularly using the imaging method used. Advantageously, the outer diameter of the cannula of the implantation device is provided to be less than 3 mm, preferably 1.6 mm to 1.2 mm. This leads to the advantage that the marking body can be implanted percutaneously, particularly due to the small cannula diameter. In particular, the small outer cannula diameter facilitates implantation of the marking body without the need to rely on a stab incision of the skin at the cannula entry site or the administration of anesthesia for the relevant tissue.

[0050] As a result of the overall system, the marking body can be applied together with a suitable implantation device that is compatible in terms of dimensions. In particular, the implantation system as an overall system comprising both the marking body and the implantation device may, in the delivered state, include the marking body already in a compressed state within the cannula; thus, the method steps of compressing the marking body and pre-loading the implantation device are saved for the user, and application is further simplified in this way. A method for producing a marking body is also proposed according to the invention, which comprises the following steps: providing a tubular braided mesh formed by 5 to 96 braided individual wires;

[0051] - clamping the braided wire mesh at the central longitudinal section so that the braided wire mesh is expanded longitudinally on both sides, starting from the central longitudinal section, to form two flared longitudinal sections. Preferably, the method comprises the following further method steps:

[0052] - braiding the individual wires to form a tube such that the individual wires alternately cross over and under each other at intersections, the intersections being located approximately in an intersection plane that extends transversely to the longitudinal axis of the tube;

[0053] - separating the tube sections by laser cutting the wire at all intersections in a separation plane, the intersection plane, to provide a tubular braided wire mesh. The tubular braided wire mesh, separated from the tube, can then be formed into a marking body.

[0054] Preferably, the individual wires are pairwise welded to each other when separated.

[0055] Preferably, the individual wires are wrapped around each other in a plane of intersection that serves as a separation plane, with each two individual wires wrapped around each other through at least 180°, preferably 360°, 540°, or 720°.

[0056] Preferably, the individual wires cross over or under each other between the longitudinal ends of the tubular braided wire mesh 8 to 12 times, preferably 9 to 11 or 10 times, and thus every 9 to 13th, preferably every 10th, 11th or 12th intersection plane of the tubing braided from the individual wires represents a separation plane where the individual wires are twisted around each other, preferably in pairs.

[0057] Marking bodies of the type presented here serve for percutaneous marking in soft tissue, for example breast tissue, and for marking axillary lymph nodes following lymph node biopsy.

[0058] The field of this application includes marking suspicious tissue, marking lesions before or during chemotherapy, and marking biopsy removal sites. The location of removed tumors can also be marked for improved orientation within radiation treatment plans. Marking bodies can also be used within the intervention, as described below.

[0059] The marking body is first implanted at the desired site by inserting the distal end of the cannula of the implantation device into the body tissue to the desired implantation location and then expelling the marking body from the distal end of the cannula. Alternatively, the cannula tip of the implantation device can be brought to the desired implantation location through a port already installed in the patient.

[0060] Subsequently, the body tissue can be examined using an imaging ultrasound method, and an ultrasound recording of the marked tissue is made, and the marking body can be recognized in the ultrasound recording due to a circular or X-shaped artifact.

[0061] Preferably, the marking body is used to mark adipose tissue, muscle tissue, tumor tissue, breast tissue, liver tissue, and / or lymph nodes, in particular axillary lymph nodes. Further advantages, features and details of the invention arise from the following description and illustrations of preferred embodiments. The present specification also provides, for example, the following items: (Item 1) A marking body (100) for marking body tissue, said marking body (100) comprising: - at least approximately rotationally symmetric about its longitudinal axis (110); - formed by interconnected elastic preformed metal webs (103), -capable of being in a radially compressed state and a radially expanded state; the marking body (100) in its expanded state is fastened at a central longitudinal section (106; 306; 706; 1112) and, starting from the central longitudinal section (106; 306; 706; 1112), is expanded in the longitudinal direction on both sides, and has two flared longitudinal sections (102, 104; 302, 304; 506, 508; 702, 704; 1114, 1116) whose maximum outer diameters (A1; A2; A3; A4) are 2 to 20 times larger than the outer diameter (BKA) of the central longitudinal section (106; 306; 706; 1112) of the marking body (100) in the expanded state, The marking body (100), at least in the flared longitudinal sections (102, 104; 302, 304; 506, 508; 702, 704; 1114, 1116), is formed by 5 to 96 circumferential webs (103), which, in their compressed state, extend substantially in the longitudinal direction of the marking body (100) and are interconnected in a press-fit, interlocking, and / or cohesive manner. A marking body (100) characterized by: (Item 2) Item 1: The marking body (100) according to item 1, characterized in that the web (103) of the marking body (100) is formed by 5 to 96 wires (308; 1102), each of which extends from one end of the longitudinal ends (1106, 1108) of the marking body (100) to the other end and crosses each other multiple times, thus forming a lattice-like support structure with multiple intersections (105; 310; 1110). (Item 3) 3. The marking body (100) according to claim 1 or 2, characterized in that the webs (103) of the marking body (100) are interconnected in a cohesive manner, in particular by welding at the intersections (105; 310; 1110). (Item 4) The marking body (100) according to at least one of items 1-3, characterized in that the webs (103) of the marking body (100) are twisted together at their longitudinal ends (1106, 1108). (Item 5) 5. A marking body (100) according to at least one of items 1-4, characterized in that the webs (103) of the marking body (100) are interconnected in pairs at their respective longitudinal ends (1106, 1108), in particular by welding and / or twisting. (Item 6) The marking body (100) according to at least one of items 1 to 5, characterized in that the outer diameter (BKA) of the marking body (100) increases continuously in the longitudinal direction starting from the central longitudinal section (106; 306; 706; 1112) towards both longitudinal ends (1106, 1108) when the marking body is in its expanded state, and the marking body (100) has its maximum diameter at its two longitudinal ends (1106, 1108). (Item 7) The marking body (100) according to at least one of items 1-5, characterized in that the outer diameter (BKA) of the marking body (100) when the marking body is in its expanded state first increases in the longitudinal direction starting from the central longitudinal section (106; 306; 706; 1112) towards both longitudinal ends (1106, 1108) and then decreases again to the longitudinal ends (1106, 1108), so that the marking body (100) has its maximum diameter at a certain distance from their respective longitudinal ends (1106, 1108). (Item 8) 8. Marking body (100) according to at least one of items 1-7, characterized in that the web (103) of the marking body (100) consists of a titanium alloy, in particular Nitinol. (Item 9) The marking body (100) according to at least one of items 1-8, characterized in that the central longitudinal section (106; 306; 706; 1112) is provided with a sleeve (1122) that compresses the central longitudinal section (106; 306; 706; 1112) to a minimum diameter. (Item 10) 10. The marking body (100) according to at least one of items 1-9, wherein at least one web (100) is at least partially hollow. (Item 11) An implantation system (1000) having a marking body (100) according to any one of items 1-10 and an implantation device (1004) with a cannula (1006), wherein the marking body (100) is positioned within the cannula (1006) and can be moved out of the cannula (1006) by actuating the implantation device (1004). (Item 12) Item 12. An implantation system (1000) according to item 11, characterized in that the implantation system (1000) is designed for application in a vacuum biopsy unit, in particular in a vacuum biopsy anchor with a cannula (1006) having a lateral opening for delivering the marking body (100). (Item 13) 1. A method for producing a marking body (100) for marking body tissue, the method comprising: - providing a tubular braided wire mesh (200; 301; 1104; 1200) having two longitudinal ends and formed by 5 to 96 braided individual wires (308; 1102); - fastening said braided wire mesh (200; 301; 1104; 1200) at the central longitudinal section (106; 306; 706; 1112) so that said braided wire mesh (200; 301; 1104; 1200) is expanded in the longitudinal direction on both sides, starting from said central longitudinal section (106; 306; 706; 1112), to form two flared longitudinal sections (102, 104; 302, 304; 506, 508; 702, 704; 1114, 1116); A method comprising: (Item 14) - separating, in particular cutting, the braided wire mesh (200; 301; 1104; 1200) in a plane extending transversely to the longitudinal direction of the braided wire mesh (200; 301; 1104; 1200); - removing the separated portions of said braided wire mesh (200; 301; 1104; 1200); Item 14. The method of item 13, further comprising: (Item 15) - The method according to item 14, further comprising a step of connecting the free ends (312; 1118) of the braided wire mesh (200; 301; 1104; 1200) resulting from the separation, the connection being possible before or after the separation by twisting and / or before, during or after the separation by welding. [Brief explanation of the drawings]

[0062] [Figure 1] FIG. 1 shows a marking body diagrammatically represented in a side view.

[0063] [Figure 2] FIG. 2 shows the marking body shown in FIG. 1 in an end view.

[0064] [Figure 3] FIG. 3 shows the marking body diagrammatically represented in a side view.

[0065] [Figure 4] FIG. 4 shows the marking body shown in FIG. 3 in an end view.

[0066] [Figure 5] FIG. 5 shows the marking body diagrammatically represented in a side view.

[0067] [Figure 6] FIG. 6 shows the marking body shown in FIG. 5 in an end view.

[0068] [Figure 7] FIG. 7 shows the marking body diagrammatically represented in a side view.

[0069] [Figure 8] FIG. 8 shows the marking body shown in FIG. 7 in an end view.

[0070] [Figure 9] FIG. 9 illustrates various stages of a production method for producing a marking body.

[0071] [Figure 10] 10A, B, and C show diagrammatically an embedding system having a marking body and an embedding device.

[0072] [Figure 11] FIG. 11 shows a marking body in which the support structure is formed by 24 wires.

[0073] [Figure 12]FIG. 12 shows a further view of the marking body shown in FIG. 11, where the end side of the marking body is now visible.

[0074] [Figure 13] FIG. 13 shows a side view of the marking body from FIGS. 11 and 12 together with a scale.

[0075] [Figure 14] FIG. 14 shows an end view of the marking body from FIGS. 11 and 12 together with a scale.

[0076] [Figure 15] FIG. 15 shows a perspective view of the marking body depicted in FIGS.

[0077] [Figure 16] FIG. 16 shows a marking body made from a braided wire mesh similar to the marking bodies depicted in FIGS.

[0078] [Figure 17] FIG. 17 shows a marking body made from a braided wire mesh similar to the marking body depicted in FIG. 16 with an additional central sleeve.

[0079] [Figure 18] FIG. 18 shows a braided wire mesh as a section of braided tubing that can be used as an initial product for forming marking bodies such as those depicted in FIGS.

[0080] [Figure 19] FIG. 19 shows a section of a tube woven from wire from which three braided wire meshes according to FIG. 18 can be produced by separation.

[0081] [Figure 20] FIG. 20 shows the braided wire tube from FIG. 19 where the wires have been separated in two locations using a laser.

[0082] [Figure 21] FIG. 21 shows a perspective view of the marking element depicted in FIG.

[0083] [Figure 22] FIG. 22 shows a further side view of the marking element depicted in FIG.

[0084] [Figure 23] 23a-23h show different cross-sectional shapes for the web of marking bodies according to FIGS.

[0085] [Figure 24] Figures 24a-24f show different variations of how the webs of individual marking bodies from Figures 1 and 2 can be interconnected at their intersections.

[0086] [Figure 25] Figures 25a-25f show different variants of how the free ends of two webs of marking bodies according to Figures 1 and 2 can be connected.

[0087] [Figure 26] 26a-26b show plan views of an embedding device for marking bodies according to FIGS. 1-25.

[0088] [Figure 27] FIG. 27 shows a further view of the implantation device of FIG.

[0089] [Figure 28] FIG. 28 shows an ultrasound image with marking body artifacts as viewed from the side.

[0090] [Figure 29] FIG. 29 shows an ultrasound image with a marking body artifact in the longitudinal direction. DETAILED DESCRIPTION OF THE INVENTION

[0091] 1 shows a side view of a diagrammatically illustrated marking body 100. FIG. 2 shows an end view of the same marking body 100.

[0092] The marking body 100 is formed from a laser cut tube.

[0093] The marking body 100 is depicted in an expanded state and has two flared longitudinal sections 102, 104 and one central longitudinal section 106 positioned between the two longitudinal sections 102, 104.

[0094] Each of the two flared longitudinal sections 102, 104 flares out in a conical manner, starting from the central longitudinal section 106. Thus, the outer diameters of the flared longitudinal sections 102, 104 increase continuously, starting from the central longitudinal section 106. Each flared longitudinal section 102, 104 has a maximum outer diameter at a respective longitudinal end of the marking body 100.

[0095] In the two flared longitudinal sections 102, 104, the marking body 100 has a mesh-like support structure, with numerous intersections 105 formed by webs 103. To place the marking body 100 in its elastically compressed state, the web-like support structures in the two flared longitudinal sections 102, 104 can be radially pressed together, causing the mesh 108 within each support structure to move toward the longitudinal axis 110 of the marking body. The effective length of the marking body 100 is therefore longer in the compressed state than in the expanded state. To place the marking body 100 in its elastically compressed state, a radial force of at least 1 Newton must be exerted on the marking body 100 in the two flared longitudinal sections 102, 104. As a result, the marking body 100 is designed to exert a radial force of approximately 1 Newton on the surrounding tissue when in the compressed state and to expand when the opposing tissue force is less than 1 Newton. In an embodiment not shown here, the marking body comprises a web with a web thickness different from the web thickness of web 103, whereby a relatively greater radial force, e.g., at least 1.5 Newtons, must be exerted on the marking body to elastically compress it.

[0096] In the central longitudinal section 106, the tube is not cut by the laser and therefore has a closed sleeve-shaped support structure.

[0097] The marking body 100 is rotationally symmetric about its longitudinal axis 110. In its expanded state, the marking body 100 has a length L1 of 7 mm. The tube in which the marking body 100 is formed has an inner diameter of 0.458 mm, an outer diameter of 0.762 mm, and a wall thickness of 0.152 mm. In the central longitudinal section 106, the marking body 100 retains its original dimensions after it is cut by a laser in adjacent longitudinal sections 102, 104. By way of example, the marking body 100 may be formed from a titanium alloy, in particular, Nitinol.

[0098] In embodiments not shown here, the marking body has different dimensions but is otherwise formed by a tube that is laser cut to form a marking body with a central longitudinal section and two flared longitudinal sections emanating therefrom, as described in connection with Figure 1. By way of example, such a tube can have an outer diameter of 0.6 mm to 0.08 mm, an inner diameter of 0.3 mm to 0.5 mm, and a wall thickness of 0.1 mm to 0.5 mm.

[0099] In the flared longitudinal sections 102, 104, the maximum outer diameter A1 of the marking body 100 is 3.5 mm, and in alternative embodiments can be, for example, 3 mm to 4 mm. In the central longitudinal section 106, the inner diameter I1 is 0.458 mm.

[0100] Figure 3 shows a side view of the marking body 100, which is diagrammatically illustrated in an expanded state. Figure 4 shows an end view of the marking body 100.

[0101] The marking body 100 comprises a support structure formed by a braided wire mesh 301. Wires 308 extend from one longitudinal end of the marking body 100 to the other longitudinal end. On their way from one longitudinal end to the other, the wires 308 cross over other wires 308, and they are in particular braided, i.e., each wire 308 is alternately guided first below and then above another wire 308 of the braided wire mesh 301. As a result, a mesh-like support structure with numerous intersections 310 results. It should be observed that these intersections 310 (where two wires 308 in each case contact) welded to one another or wrapped around one another are not reproduced in exact detail in relation to the representations depicted in Figures 3 and 4. The intersections 310 where two wires 308 in each case contact can be designed, for example, as in a braided wire mesh formed by crossing the wires of the marking body, as similarly described and depicted in relation to Figures 11 and 12.

[0102] 11 and 12, the wires 308 are welded, i.e., cohesively interconnected, to one another at the intersections 310. As an alternative or in addition to welding, the wires 308 can also be wrapped around one another at the intersections 310. In particular, each of the free ends 312 of the wires 308 located at the respective longitudinal ends 314, 316 of the marking body 100 is welded to one or more free ends of additional wires 308.

[0103] 1 and 2, the marking body 100 has flared longitudinal sections 302, 304 and a central longitudinal section 306 disposed between the flared longitudinal sections 302, 304. The outer diameters of the two flared longitudinal sections 302, 304 increase continuously starting from the central longitudinal section 306 toward the longitudinal ends of the marking body 100. The outer diameters of the marking body 100 in the two longitudinal sections 302, 304 are therefore at maximum values ​​at the respective longitudinal ends.

[0104] The braided wire mesh 301 comprises 24 wires made of Nitinol and having a diameter of 0.12 mm. In an alternative embodiment of the marking body not shown here, the braided wire mesh comprises 10 to 40 wires, which are welded to each other at their intersections and / or wrapped around each other. In an embodiment not shown here, the marking body comprises a braided wire mesh formed by wires with diameters ranging from 0.10 mm to 0.14 mm. Wires made of titanium alloys other than Nitinol can also be used.

[0105] The marking body 100 has a length L2 of 6 mm, however, in alternative embodiments not shown here, this length may range from 5 mm to 7 mm.

[0106] The central longitudinal section 306 of the marking body 100 comprises a sleeve, in particular a nitinol sleeve 318 , which compresses the braided wire mesh 301 to a defined outer diameter within the central longitudinal section 306 .

[0107] The maximum outer diameter A2 of the marking bodies in the two flared longitudinal sections 302, 304 is 4 mm, and can be 3.5 mm to 4.5 mm in alternative embodiments not shown here.

[0108] To bring marking body 100 from an expanded state to a resiliently compressed state, a radial force of at least 1 Newton must be exerted on marking body 100. As a result, marking body 100 is designed to exert a radial force of approximately 1 Newton on the surrounding tissue when in a compressed state, and to expand when the opposing tissue force is less than 1 Newton.

[0109] In alternative embodiments not shown here, the self-expanding marking body 100 may have more wires, and therefore more intersections, and therefore the marking body is relatively more rigid. Therefore, a relatively larger radial force is then required to bring the marking body into its elastically compressed state. Similarly, the number of wires can be fewer in alternative embodiments not shown here to achieve a marking body that is already transitioning to its elastically compressed state when a radial force of less than 1 Newton is exerted.

[0110] The expanded marking body 100 shown in side view in Figure 5 has a spiral support structure. Figure 6 shows the marking body 100 in end view.

[0111] The central longitudinal section 502 comprises one turn, but in alternative embodiments not shown here, it may comprise multiple turns, preferably with a constant outer diameter. Each side of the central longitudinal section 502 is flanked along the longitudinal axis 504 of the marking body 100 by respective flared longitudinal sections 506, 508, whose outer diameters increase continuously, starting from the central longitudinal section 502. That is, starting from the central longitudinal section, the outer diameter of the marking body 100 increases with each turn. In the expanded state of the marking body 100 shown here, the spiral support structure has an angle W1 that is 30°. The marking body 100 can be elastically compressed by pulling the spiral support structures apart, thereby reducing the angle. To elastically compress the marking body 100, a radial force of at least 1 Newton must be exerted on it. As a result, the marking body 100 is designed to exert a radial force of approximately 1 Newton on the surrounding tissue when in a compressed state, and to expand when the opposing tissue force is less than 1 Newton.

[0112] The marking body 100 has a length L3 of 6 mm, however, in alternative embodiments not shown here, this length may range from 5 mm to 7 mm.

[0113] The maximum outer diameter A3 of the marking body 100 in the flared longitudinal sections 506, 508 is 5 mm, and in alternative embodiments not shown here it is 4 mm to 6 mm, but in particular can also be less than 4 mm.

[0114] Figure 7 shows a side view of the expanded marking body 100. Figure 8 shows the marking body 100 in an end view.

[0115] The marking body 100 has two flared longitudinal sections 702, 704 and one central longitudinal section 706 positioned between the two flared longitudinal sections 702, 704. Similarly, like the marking body described in connection with Figures 1 and 2, the marking body 100 is also formed from a laser-cut tube. In particular, the marking body 100 is laser-cut in the two flared longitudinal sections 702, 704 and not laser-cut in the central longitudinal section 706. Thus, in the expanded state, the marking body 100 has a lattice-like support structure in the two flared longitudinal sections 702, 704, while the support structure is closed and sleeve-like in the central longitudinal section 706.

[0116] 1 and 2, the marking body 100 does not expand continuously in the two flared longitudinal sections 702, 704 to the longitudinal ends of the marking body 100, but only from the central longitudinal section to approximately the center of each flared longitudinal section 702, 704. The outer diameter of the marking body in each flared longitudinal section 702, 704 is then substantially constant in the direction of each longitudinal end of the marking body 100.

[0117] In an alternative embodiment not shown here, the outer diameter of the marking body is not constant between approximately the center of each flared longitudinal section and the longitudinal end of each marking body, but is reduced so that the shape of each flared longitudinal section is at least approximately spherical or elliptical.

[0118] The marking body 100 has a length L4 of 7 mm; however, in alternative embodiments not shown, this length ranges from 4 mm to 10 mm. In the central longitudinal section 706, the dimensions of the marking body 100 correspond to the original dimensions of the tube from which the marking body 100 is formed. In the central longitudinal section 706, the marking body 100 has an outer diameter of 0.762 mm, an inner diameter of 0.458 mm, and a wall thickness of 0.152 mm. In alternative embodiments of the marking body not shown, it has an outer diameter ranging from 0.6 mm to 0.08 mm, an inner diameter ranging from 0.3 mm to 0.5 mm, and a wall thickness ranging from 0.1 mm to 0.5 mm in the central longitudinal section.

[0119] In the two flared longitudinal sections 702, 704, the maximum outer diameter A4 of the marking body 100 is 3.5 mm, but in alternative embodiments not shown here, it can range from 3 mm to 4 mm. The inner diameter I2 of the marking body 100 is 0.458 mm in the central longitudinal section 706.

[0120] To elastically compress the marking body 100, a radial force of at least 1 Newton must be exerted on it. When the marking body 100 is implanted in tissue, it will independently transition to its expanded state and maintain it if the radial force exerted on the marking body 100 by the tissue is less than 1 Newton. As a result, the marking body 100 is designed to exert a radial force of approximately 1 Newton on the surrounding tissue when in a compressed state, and to expand if the opposing force of the tissue is less than 1 Newton.

[0121] 9 illustrates various stages of a method for producing a marking body having a support structure formed by a braided wire mesh. As an example, a marking body such as that described in connection with FIGS. 3 and 4 can be produced according to the method described below.

[0122] First, a tubular braided wire mesh is provided in step S1, which may comprise, for example, 20 to 40 individual wires that are woven together and consequently cross at intersections, where the wires are preferably cohesively interconnected or wound around one another.

[0123] The sleeves are pressed onto the tubular braided wire mesh such that a section of the braided wire mesh is exposed between the two sleeves and the two sleeves are coaxially aligned relative to one another.

[0124] The sleeves are then moved toward each other in the longitudinal direction of the tubular braided wire mesh, i.e., without any relative movement between each sleeve and the braided wire mesh enclosed thereby, resulting in the braided wire mesh exposed between the sleeves being compressed longitudinally and flared radially (step S2).

[0125] The two sleeves can be moved towards each other until the braided wire mesh is partially engaged (step S3).

[0126] Additionally, the braided wire mesh is tightened in a central longitudinal section at the center of the exposed braided wire mesh (step S4), for example, by wrapping a nitinol wire around the braided wire mesh. This can be done before or after flaring and optional indentation.

[0127] The braided wire mesh can then be cut perpendicular to the longitudinal direction of the braided wire mesh on both sides of the central longitudinal section, and the cut braided wire mesh, e.g., the inlaid portion, can be removed. Preferably, the cuts are made at intersections of the already existing braided wire mesh that lie on a plane extending transversely to the longitudinal direction of the braided wire mesh. As a result, the longitudinal ends of the wires are interconnected in pairs.

[0128] If the cut is not implemented at an already existing intersection point, and free ends of the braided wire mesh are therefore generated, these free ends can be wrapped around each other and / or welded to each other.

[0129] 10A shows an implantation system 1000 having a marking body 100 of an implantation device 1004. In this case, the marking body 100 in a pre-loaded state (i.e., with a compressed support structure) is positioned within a cannula 1006 of the implantation device 1004. This state of the implantation system 1000 represents a typical delivery state, in which the implantation system 1000 is available to a user, e.g., a surgeon, in a ready-to-use state.

[0130] The implantable part 1008 of the implantable device 1004 consists essentially of a cannula 1006, which has a cannula tip 1012 at its distal end (i.e., the end remote from the handle 1010). As a rule, the marking body 100 in the pre-loaded state is located in this region within the cannula 1006 just inside the exit at the cannula tip 1012. In particular, the cannula 1006 can be formed from a suitable metal.

[0131] The cannula 1006 has a length LKA, which can range, for example, from 25 mm to 200 mm, preferably from 50 mm to 150 mm. The length LKA of the cannula 1006 affects the reach of the implantable device 1004 in terms of its ability to reach tissue sites within the patient's body to be marked. Longer cannulas are used when alignment aids are used (e.g., for stereotactic procedures).

[0132] The implantation device 1004 comprises a handle 1010 and an implantation part 1008. The handle 1010 comprises a handle housing 1014 and a sliding element 1016, which may be made, for example, from a suitable plastic.

[0133] The slide element 1016 is connected to the handle housing 1014 but is movable axially of the cannula 1006 relative to the handle housing 1014. As a result, the slide element 1016 can be moved along a linear guided slide path between a preloaded position 1020 and a delivery position 1020.

[0134] This movement is transmitted from the sliding element 1016 via a delivery element 1018 (which is connected to the sliding element 1016 and may be formed, for example, using a wire or a sufficiently stable plastic fiber) to a distal region at a distance from the handle 1010. As a result, when the sliding element 1016 is moved to a delivery position 1020, the pre-loaded marking body 100 can be delivered from the cannula 1006 to the tissue site to be marked at the distal end of the cannula 1006 using the sliding movement of the delivery element 1018.

[0135] This is accomplished by the delivery element 1018, which is aligned coaxially with the cannula 1006, being moved toward the cannula tip 1012, thus pushing the pre-loaded marking body 100 out of the cannula 1006 and beyond the cannula tip 1012.

[0136] 10B depicts a detailed view of Detail B of FIG. 10A , specifically in the region of the cannula tip 1012 of the implantation system 1000 in a pre-loaded state. In this view, the marking body 100 can be seen, in particular, in a compressed state, positioned within the cannula 1006, from the perspective of the handle 1010, behind the delivery element 1018 and in front of the cannula tip 1012. Due to its pre-stress, the marking body maintains its position within the cannula 1006 and cannot dislodge on its own. Due to this characteristic, additional features or devices for securing the marking body 1000 within the cannula 1006 can be omitted.

[0137] 10C is a more detailed schematic view of cannula 1006, here as detail C from FIG. 10B. In this view, the distal end of delivery element 1018 is visible within cannula 1006. Additionally, the outer diameter DKA and inner diameter DKI of cannula 1006 are also labeled.

[0138] The internal diameter DKI of the cannula 1006, together with the cannula length LKA, describes the size of the internal cavity formed by the cannula 1006 and at the same time limits the maximum possible diameter DM of the marking body 100 in the compressed state or, optionally, the maximum possible diameter DK of the at least one clamp 105, in order to ensure the ability of the marking body 100 to pass through or move within the cannula 1006 during preloading and delivery. An internal diameter DKI of less than 1.1 mm, particularly preferably 1.0 mm, has been found to be preferred.

[0139] The outer diameter DKA of the cannula 1006 describes the diameter of the outer cannula wall. Under the assumption of a constant cannula wall thickness that is as thin as possible, the small inner diameter DKI of the cannula 1006 simultaneously increases with an increase in the outer diameter BKA, and therefore there is also an increase in the maximum possible outer diameter of the marking body 100 to be implanted. However, at the same time, increasing the outer diameter DKA leads to a greater degree of invasiveness or injury to the skin and tissue when implanting.

[0140] A DKA of sufficiently small outer diameter ensures the option of percutaneous implantation of the marking body 100 without the need to rely on a stab incision of the skin or anesthesia of the involved tissue at the entry site of the cannula 1006. DKAs of 1 mm to 1.5 mm, particularly preferably 1.2 mm, outer diameter have been found to be preferred.

[0141] Figure 11 shows a side view of the expanded marking body 100. Figure 12 shows the marking body 100 in a further view, where one of the end sides of the marking body 100 is visible.

[0142] The marking body 100 has a support structure formed by 24 individual preformed wires 1102. The support structure is formed as a braided wire mesh 1104. The braided wire mesh 1104 is formed from crossing wires 1102 in a manner corresponding to the braided wire mesh 301 of the marking body 100 described in connection with Figures 3 and 4. The wires of the braided wire meshes 1104 and 301 can be preformed elastic wires.

[0143] The wires 1102 extend in a helical manner around the longitudinal axis of the marking body 100 from one longitudinal end 1106 of the marking body 100 to the opposite longitudinal end 1108 of the marking body 100. On their path from one longitudinal end 1106 to the other longitudinal end 1108 of the marking body, the wires 1102 weave with one another and are guided under and over other wires of the support structure multiple times so that they form a braided wire mesh 1104. Intersections 1110 occur at locations in the braided wire mesh 1104 where the wires 1102 are guided under or over other wires 1102. The wires 1102 of the braided wire mesh 1104 are not cohesively interconnected at the intersections 1110 but simply contact one another. In an alternative exemplary embodiment not shown here, the wires at the intersections can be welded to one another, as in the marking bodies described in connection with FIGS. 3 and 4, for example.

[0144] The wire 1102 is guided diagonally from one longitudinal end 1106 to the other longitudinal end 1108 of the marking body 100 so that the marking body 100 is clamped at a central longitudinal section 1112 .

[0145] Starting from the central longitudinal section 1112, the outer diameter of the marking body 100 increases continuously on both sides so that the marking body 100 has two conical flared longitudinal sections 1114, 1116. The outer diameter of the marking body 100 at the flared longitudinal sections 1114, 1116 has a maximum value in each case at both longitudinal ends 1106, 1108 of the marking body 100.

[0146] The angle at which the marking body 100 flares in the flared longitudinal sections 1114, 1116 in the expanded state can be, for example, 30°, particularly 25°-35° from the central axis. The wire 1104 is formed from Nitinol.

[0147] At the free ends 1118 of the wires 1102 located at the longitudinal ends 1106, 1108 of the marking body 100, two adjacent wires 1102 are wound around each other or welded together. A The diameter difference between the weld bead diameter D and S A weld bead 1120 with a marking body 1124 results from the weld. This prevents the marking body, and in particular the weld bead of the marking body, from getting stuck between the distal end section of the delivery element 1018 and the inner wall of the cannula. To this end, the distal end of the delivery element 1018 is preferably formed with a sharp edge, because rounded or chamfered edges can result in the marking body getting stuck, thereby preventing the marking body from becoming embedded.

[0148] The marking body 100 is designed so that a radial force of at least 1 Newton must be exerted on the marking body 100 to compress it to a diameter of less than 1.5 mm.

[0149] The marking body 100 can have a sleeve, for example a nitinol sleeve 1122, disposed within the central longitudinal section 1112, as in the marking body 100 described with reference to Figures 3 and 4. A corresponding marking body 100' is depicted in Figure 17.

[0150] The dimensions of marking body 100 or 100', together with the scale, are taken from Figures 13, 14, 16, and 17, which show marking body 100 in its expanded state. In its expanded state, the marking body has a length of about 6 mm to 7 mm (see Figure 13) and a maximum outer diameter of about 5 mm (see Figure 14).

[0151] 15 is an idealized perspective representation of the marking body 100. The representation in FIG. 15 shows the basic structure, but idealized in terms of the representation of the intersections and free interconnected longitudinal ends 1118 of the wires 1102.

[0152] As can be seen from FIG. 16, the marking body 100 preferably has a length L ranging from 5 mm to 8 mm. The outer diameter D in the fully expanded state is between 4 mm and 6 mm. The clamped central longitudinal section 1112 has a diameter d of less than 1.5 mm. The diameter of the individual wires 1102 is preferably slightly less than 0.1 mm. The weld beads 1120 at the free ends 1118 of the wires have a diameter greater than 0.1 mm, which is preferably at least 0.12 mm. Thus, the marking body 100 is preferably at least 0.12 mm in diameter relative to the inner cannula diameter DKI and the delivery element outer diameter D. A is suitable for use with implantable device 1004, where the difference between is 0.1 mm or less, even when manufacturing tolerances are taken into account.

[0153] 16, it can be seen that the free longitudinal ends 1118 of the wires 1102 are not only welded to one another, but are also wrapped around one another. This together ensures that the interconnected longitudinal ends of the wires do not separate from one another because forces resulting from prestress within the cannula do not act in their entirety on the weld site, but are absorbed, either partially or entirely, by the twisting.

[0154] Unlike what is depicted in an idealized manner in the figures, the longitudinal ends of the individual wires 1102 do not all lie exactly within one (separating) plane 1212 (see FIGS. 19 and 20), but instead are preferably slightly offset longitudinally relative to such idealized plane. This has the advantageous effect that the marking body 100 can be better compressed at its longitudinal ends 1118, since the weld beads 1120 are not all located next to each other but are at least partially offset from each other in the longitudinal direction of the marking body 100.

[0155] In its fully expanded state, the flared longitudinal sections 1114 and 1116 adopt an angle α with respect to the longitudinal axis of the marking body 100, the angle preferably being between 30° and 45°.

[0156] In the clamped central longitudinal section, the marking body 100' may have a sleeve 1122, which in any case keeps the marking body 100' compressed in this central longitudinal section 1112. The sleeve 1122 may be made of the same material as the individual wires 1102, specifically, preferably, Nitinol. However, the sleeve 1122 may also preferably be made of a radiopaque material, for example, gold. The sleeve 1122 is preferably welded to at least one of the wires 1102 using at least one welding spot 1124 and is thus fixed against displacement. The wire ends, if provided with a sleeve 1122, do not need to be welded.

[0157] The dimensions of the marking body 100' together with the central sleeve 1122 preferably correspond approximately to those of the marking body 100. The length L2 of the marking body 100' is therefore preferably between 5 mm and 10 mm. In the fully expanded state, the maximum diameter D2 of the marking body 100' is preferably between 4 mm and 6 mm. The central sleeve 1122 preferably has a diameter d2 that is less than 2 mm, preferably less than 1.8 mm, particularly preferably less than 1.0 mm. The length h of the sleeve 1122 is preferably less than 2 mm (see FIG. 17).

[0158] The marking body 100 or marking body 100' is preferably formed from a braided wire mesh 1200, as depicted in an exemplary manner in FIG. 18. FIG. 18 shows the braided wire mesh 1200 as a section of a braided wire tube 1202 (see FIG. 19), which, in the depicted example, is woven from 24 individual wires. The braided wire mesh 1200 that will form the marking body 100 or 100' is formed from 24 individual wires 1102, which cross under or over each other nine times between their longitudinal ends 1118, and which are wrapped around each other and welded to each other in pairs at their longitudinal ends 1118 so that the braided wire mesh 1200 has respective weld beads 1120 at the longitudinal ends 1118 of the wires 1102. As can be seen from FIG. 18, the longitudinal ends 1118 of the interconnected wires 1102 are not only welded to each other, but are also wrapped around each other.

[0159] In another embodiment, the marking body 100' can be made from a simple braided wire mesh 1200 without twisting 1206. In this embodiment, the wire ends do not need to be welded to each other because the sleeve 1122 keeps the braided mesh stable.

[0160] To produce the braided wire mesh 1200 depicted in FIG. 18 , a wire tube 1202 depicted in FIG. 19 is first produced. To produce the tube 1202, 24 individual wires 1102 are, for example, woven together so that they alternately cross over and under each other at intersections 1110. Intersection planes 1210 extending transversely to the longitudinal direction of the tube 1202 are thus created. When the individual wires 1102 cross each other in pairs nine times, two individual wires are wound around each other, each time creating a twist 1206. The wire tube 1202 thus forms intersection planes 1210 alternating with separation planes 1202 where each braided wire mesh 1200 should be separated from the wire tube 1202. In the illustrated example, nine intersection planes 1210 are followed by a respective separation plane 1212. In the separation plane, the wires 1102 are completely wound around each other twice as a pair, resulting in a winding angle of 720° each time. In other exemplary embodiments not shown, the winding angle can also be only 360° or 540°.

[0161] 20 shows a tube 1202 formed by wire 1102 that has been separated at two separation sites 1214 using a laser beam. Separation sites 1214 are precisely located at one separation plane 1212, i.e., where twist 1206 was located. Weld beads 1120 result from the laser cut, whereby the previously free pairwise interconnected longitudinal ends 1118 of wire 1102 are interconnected by both the twist and the laser weld.

[0162] 21 and 22 again show perspective views of the marking body 100. FIG.

[0163] Individual webs may have different diameters and cross-sectional shapes. Figures 23a-23h illustrate different cross-sectional shapes. As an example, the webs may be formed as rounded solid wires and have a cross-section as depicted in Figure 23a. Preferably, the webs are hollow wires, i.e., tube-type wires, which may have a cross-section as depicted in Figure 23b. Such hollow wires are advantageous in that they reflect sound particularly well due to the acoustic impedance difference between the wire wall material and the hollow interior. Figures 23c and 23d illustrate that the cross-sectional shape can also be square, particularly quadrilateral. Figures 23e and 23f illustrate triangular cross-sectional shapes for webs in the form of solid material (Figure 23e) or as hollow webs (Figure 23f). Figures 23g and 23h illustrate that, in principle, they can each have an arbitrary prismatic cross-sectional shape, thus a hexagonal shape, as shown in Figures 23g and 23h.

[0164] Since the marking body 100 is preferably formed from a braided wire mesh, the wires typically contact each other at intersections. The intersections can then have the appearance depicted in an exemplary manner in FIG. 24a. A fixed connection between two intersecting wires can be created at such intersections by welding. FIG. 24b illustrates this based on a weld spot 118 on the intersection. If the webs are not woven but simply contact each other laterally as an arc, as depicted in FIG. 24c, a stable marking body can also be created by the fact that the contacting webs are connected by welding, as depicted in FIG. 24d. The weld spot 118 is also shown here. Finally, the webs can be twisted at the intersections. FIG. 24e shows a twist in which the webs are wrapped 360° and then connected to each other using the weld spot 118 (see also FIG. 24f). Instead of a 360° twist, a 180° twist would also suffice. The resulting image then resembles that of Figure 24c, but the webs are now hooked together.

[0165] 25a-25f illustrate that webs can be connected not only at intersections but also at free longitudinal ends 112 by welding (FIG. 25b), by twisting (FIGS. 25c and 25e), or by twisting and welding (FIGS. 25d and 25f). Typically, weld beads 120 having a larger diameter than the individual webs 103 or wires forming webs 103 then result from welding web 103 to its free longitudinal ends 112.

[0166] Figures 26 and 27 finally show an implantation device 1004 for implanting the marking body 100. As already explained in conjunction with Figure 10, the implantation device 1004 comprises a handle 1010 and an implantation part 1008. A cannula 1006, in which the marking body 100 is initially positioned, is part of the implantation part 1008.

[0167] Figure 26a shows the implantation device 1004 with the slide element 1016 and the delivery element 1018 in the pre-loaded position. The resulting implantation system 1000 is ready for use and includes the marking body 100 (which is not visible because it is located within the cannula 1006). A protective sleeve 1024 is provided for protection against injury. Figure 26b shows the implantation device 1004 with the slide element 1016 and the delivery element 1018 in the delivery position with the marking body ejected.

[0168] A cannula tip 1012 at the distal end of the cannula 1006 is polished to facilitate percutaneous implantation of the marking body 1100 by piercing the cannula 1006 into body tissue. The cannula 1006 is preferably made of stainless steel.

[0169] To expel the marking body 100 from the cannula 1006 , a displaceable delivery element 1018 is provided, which can be actuated from the handle 1010 by means of a slide element 1016 .

[0170] Using an implantation device, marking bodies of the type presented here for percutaneous marking can be implanted into soft tissue such as breast tissue, or into axillary lymph nodes following lymph node biopsy.

[0171] The field of the present application includes the marking of suspicious tissue, the marking of lesions before or during chemotherapy, and the marking of biopsy removal sites. The location of removed tumors can also be marked for improved orientation within radiation treatment planning. As an example, within interventions, marking bodies are used as follows:

[0172] First, the marking body is implanted at the desired site by inserting the distal end 1012 of the cannula 1006 of the implantation device 1004 into the body tissue to the desired implantation location, and then expelling the marking body 100 from the distal end 1012 of the cannula 1006.

[0173] Subsequently, the body tissue can be examined using an imaging ultrasound method, and an ultrasound recording of the marked tissue is made. The marking body can be recognized in the ultrasound recording due to a circular artifact 1300 or an X-shaped artifact 1302 (see FIGS. 28 and 29). (List of reference symbols) 100 marking body 102, 104 Flared vertical sections 103 Web 105 intersection 106 Central longitudinal section 108 mesh 110 Vertical Axis 118 Welding Spot 120 welding beads L1 Length of marking body A1 Maximum outer diameter of marking body in flared longitudinal section I1 Inner diameter of the marking body in the central longitudinal section 301 Braided Wire Mesh 302, 304 Flared vertical sections 306 Central longitudinal section 308 Wire 310 intersection 312 Free end of wire L2 Length of marking body A2 Maximum outer diameter of marking body in flared longitudinal section 502 central vertical section 504 Vertical axis of marking body 506, 508 Flared vertical sections W1 Angle of volute support structure L3 Marking body length A3 Maximum outer diameter of marking body in flared longitudinal section 702, 704 Flared vertical sections 706 Central longitudinal section L4 marking body length A4 Maximum outer diameter of marking body in flared longitudinal section I2 Inner diameter of marking body in central longitudinal section S1 Tubular Braided Wire Mesh Offering S2 Compression of tubular braided wire mesh in its longitudinal direction S3 Partial indentation of braided wire mesh S4 Tightening of the braided wire mesh in the central longitudinal section DKI inner cannula diameter DKA outer cannula diameter BKA outer diameter LKA cannula length 1000 Embedded Systems 1004 Implantation Device 1006 Cannula 1008 Embedded parts 1010 Handle 1012 Cannula tip 1014 Handle housing 1016 Slide Elements 1018 Sending Elements 1020 Preloaded Position 1022 Sending position 1024 Protective Sleeve 1102 Wire 1104 Braided Wire Mesh 1106, 1108 Vertical end of marking body 1110 intersection 1112 Central longitudinal section 1114, 1116 Flared vertical sections 1118 Longitudinal edge of web 1120 Welding beads 1122 Sleeve 1124 Welding Spot 1200 Braided Wire Mesh 1202 Wire pipe 1206 Twist 1210 Intersection plane 1212 Separation plane 1214 Separation point 1300 circular artifact 1302 X-shaped artifact

Claims

[Claim 1] A marking body (100) for marking body tissue, said marking body (100) comprising: - at least approximately rotationally symmetric about its longitudinal axis (110); - formed by interconnected elastic preformed metal webs (103), - it is capable of being in a radially compressed state and a radially expanded state, said marking body (100), when in its expanded state, is fastened at a central longitudinal section (106; 306; 706; 1112) and, starting from said central longitudinal section (106; 306; 706; 1112), is widened in said longitudinal direction on both sides and has two flared longitudinal sections (102, 104; 302, 304; 506, 508; 702, 704; 1114, 1116) whose maximum outer diameters (A1; A2; A3; A4) are 2 to 20 times larger than the outer diameter (BKA) of said central longitudinal section (106; 306; 706; 1112) of said marking body (100) in the expanded state, The marking body (100), at least in the flared longitudinal sections (102, 104; 302, 304; 506, 508; 702, 704; 1114, 1116), is formed by 5 to 96 webs (103) in the circumferential direction, which, in their compressed state, extend substantially in the longitudinal direction of the marking body (100) and are interconnected in a press-fit, interlocking and / or cohesive manner. A marking body (100) characterized by:

Images