IMPLANT AND ASSEMBLY HAVING A RADIATION SOURCE AND AN IMPLANT

Abstract

The present invention relates to an implant for implanting in a body, in particular in a hollow organ or a vessel of a body, the implant being composed of a filament which comprises at least one polymeric matrix material in which a magnetically heatable filler is arranged, the filament having a cross section with a core-sheath structure characterized in that the core forms a polymeric reinforcing structure, and in that the sheath comprises the polymeric matrix material in which the magnetically heatable filler is disposed, the loading of the filler being greater in the sheath than in the core.

Claims

1. Implant for implanting in a body, in particular in a hollow organ or a vessel of a body, the implant being composed of a filament which comprises at least one polymeric matrix material in which a magnetically heatable filler is arranged, the filament having a cross section with a core-sheath structure characterized in that the core forms a polymeric reinforcing structure, and in that the sheath comprises the polymeric matrix material in which the magnetically heatable filler is disposed, the loading of the filler being greater in the sheath than in the core.

2. Implant according to claim 1, characterized in that the core is thread-like and the sheath has a hose-like structure and at least partially envelops the core.

3. Implant according to claim 1, characterized in that the magnetically heatable filler is a superparamagnetic filler.

4. Implant according to claim 1, characterized in that the filler has a crystallite size in a range from greater than or equal to 3 nm to less than or equal to 100 nm.

5. Implant according to claim 1, characterized in that the filament has a crossed structure or an entangled structure or that the filament has a braided structure.

6. Implant according to claim 5, characterized in that the implant forms a tubular structure.

7. Implant according to claim 1, characterized in that the magnetically heatable filler is present in the sheath in a proportion of greater than or equal to 0.1% by weight to less than or equal to 90% by weight.

8. Implant according to claim 1, characterized in that the polymeric matrix material is selected from the group consisting of polypropylene, polyethylene terephthalate, polyvinylidene fluoride, polyethylene, polyamide and thermoplastic polyurethane.

9. Implant according to claim 1, characterized in that the core forms a polymeric reinforcing structure comprising the same polymeric matrix material as the sheath.

10. Implant according to claim 1, characterized in that the core is free of the magnetically heatable filler (20).

11. Implant according to claim 1, characterized in that the core-sheath structure is produced by a coextrusion process.

12. Implant according to claim 1, characterized in that the core-sheath structure forms a two-layer structure.

13. Arrangement of a radiation source for emitting electromagnetic radiation and an implant, wherein the implant comprises a magnetically heatable filler, characterized in that the implant is configured according to claim 1.

14. Arrangement according to claim 13, characterized in that the implant and the radiation source are matched to each other in such a way that the implant is heatable by electromagnetic radiation emitted by the radiation source, at least in the sheath, to a temperature which lies in a range from 40 C. to 100 C.

15. Arrangement according to claim 13, characterized in that the radiation source is arranged to emit radiation of a frequency in a range from 10 kHz to 1 MHz at a field amplitude range from 1 kA/m to 100 kA/m.

Description

[0070] It show:

[0071] FIG. 1a schematic view of a filament for an implant according to the present invention; and

[0072] FIG. 2 the mode of action of an implant according to the invention.

[0073] FIG. 1 shows a schematic view of a filament 10 for an implant 26 according to the present invention.

[0074] In particular, the implant 26 serves for implanting into a body, particularly into a hollow organ 22 of a body, as shown in FIG. 2, to fight against hollow organ tumors. In addition, the implant 26 may also be inserted into a vessel.

[0075] The implant 26 is constructed from the filament 10, for example in a braided structure. The filament 10 has at least one polymeric matrix material 18 in which a magnetically heatable, in particular superparamagnetic, filler 20 is arranged.

[0076] Further, FIG. 1 shows that the filament 10 has a cross-section with a core-sheath structure 12 such that the core 14 forms a polymeric reinforcing structure.

[0077] It is shown that the core 14 is arranged filamentary and as a fiber or filament, and the sheath 16 has a hose-like structure and at least partially envelops the core 14.

[0078] The sheath 16 comprises the polymeric matrix material 18 in which the magnetically heatable, in particular nanoscale, filler 20 is arranged. It can be seen that the loading of the filler 20 in the sheath 16 is greater than in the core 14. In particular, the core 14 is free of the filler 20. Furthermore, the core-sheath structure 12 or the filament 10 is designed in particular as a two-layer structure.

[0079] In particular, the magnetically heatable filler 20 may be present in the sheath 16 in an amount from greater than or equal to 0.1 wt % to less than or equal to 90 wt %. Further, the matrix material 18 may be selected from the group consisting of polypropylene, polyethylene terephthalate, polyvinylidene fluoride, polyethylene, polyamide, and thermoplastic polyurethane. The material of the core 14 may be formed from the same aforementioned material.

[0080] As indicated in FIG. 2, the filament 10, which can also be referred to as a bicomponent fiber, can be processed into an implant 26, in particular a stent, with the aid of textile manufacturing processes. Preferably, braiding is mentioned here as a manufacturing process. The implant 26 can then be used, as shown in FIG. 2, in infiltrated tumors in vessels and hollow organs 22 to keep the vessels and hollow organs 22 open and for hyperthermic treatment of the tumors by destroying tumor tissue 24.

[0081] To implement this form of therapy, the implant 26 is designed as a textile stent that can be heated by magnetic induction. Here, the filament braided structure is used as the textile stent. This braided structure consists of polymer fibers having incorporated nanoferrites as filler 22. The nanoferrites to be used are synthesized and compounded together with the polymer on a twin screw extruder to form a spinnable masterbatch. This masterbatch is then spun into inductively heatable fibers using the melt spinning process. In particular, a coextrusion of core material and sheath material is carried out to create the core-sheath structure. The implant 26 or the stent, respectively, is advanced via a catheter system to the corresponding location in the body or in the hollow organ 22 or vessel and then expanded by means of self-expansion.

[0082] When excited in an electromagnetic field, the nanoferrites convert the absorbed energy of the field into heat and release it to the environment. This is made possible, for example, by using a radiation source 30 which emits electromagnetic radiation in such a way that the filler 20 heats up to preferably 43 C. The radiation source 30 can form a coherent or coordinated arrangement 28 with the implant 26.

[0083] The resulting local hyperthermia can destroy ingrown tumors or corresponding tumor tissue 24 around the implant 26. As described, this is possible in particular by using specific superparamagnetic nanoferrites with an adjustable saturation temperature as filler 20. The achievable surface temperature depends largely on the parameters of the magnetic field, which must be adjusted to the properties of the nanoferrites and the fibers incorporated with nanoferrites, and on the level of particle loading or filler loading of the filament 10. The parameter selection of the electromagnetic field is limited by compliance with medical safety limits. However, these are readily achievable according to the present invention, since the filler loading can be selected to be sufficiently high due to the reinforcing layer of the core 14.

[0084] The nanoferrites release the absorbed inductive energy as heat via the polymer fibers to the tumor tissue 24, acting as an intrinsic thermostat. In this way, the tumor tissue 24 is destroyed by a local increase in temperature, as shown in FIG. 2.

REFERENCE SIGNS

[0085] 10 filament [0086] 12 core-sheath structure [0087] 14 core [0088] 16 sheath [0089] 18 matrix material [0090] 20 filler [0091] 22 hollow organ [0092] 24 tumor tissue [0093] 26 implant [0094] 28 arrangement [0095] 30 radiation source