MEDICAL SET FOR TREATING ANEURYSMS, PRODUCTION PROCESS, AND MEDICAL SYSTEM FOR TREATING ANEURYSMS

Abstract

The invention relates to a medical set for treating aneurysms, including a main catheter and a covering device which can be moved through the main catheter to a treatment site and is intended to cover an aneurysm. The covering device is connected or can be connected to a transporting wire and includes a self-expandable grid structure made up of webs that are connected to one another in one piece and delimit inner cells and outer cells. The outer cells form at one longitudinal end of the grid structure a closed outer-cell ring, which is connected only on one side to inner cells. The grid structure is provided with a covering made of a fabric which has pores of irregular sizes, wherein at least one inner cell of the grid structure is at least partially, in particular mostly, free from the covering. A production process and a medical system are also provided.

Claims

1-15. (canceled)

16. A medical set for treatment of an aneurysm comprising: a main catheter; and a covering device adapted to move through the main catheter to a treatment site to cover the aneurysm, the covering device adapted to connect to a transport wire, the covering device including a self-expandable mesh structure having webs connected together in one piece and that delimit inner cells and edge cells, wherein at a longitudinal end of the mesh structure, the edge cells form a closed edge cell ring connected to the inner cells on only one side, wherein the mesh structure is provided with a covering produced from a fabric having pores of irregular sizes, and wherein at least one inner cell of the mesh structure is at least partially covering-free.

17. The medical set according to claim 16 wherein the covering is configured as an electrospun covering.

18. The medical set according to claim 16 wherein the covering device is reversibly connectable to the transport wire and, in an expanded state, is open on both end sides and perfusible by blood.

19. The medical set according to claim 16 wherein the webs of the inner cells are respectively associated with one of a further inner cell or edge cell, and wherein the edge cells respectively have two webs which are not associated with one of other inner cells or edge cells.

20. The medical set according to claim 16 wherein the covering ends at the webs of the inner cells which are free from the covering such that the covering does not protrude into the at least one inner cell.

21. The medical set according to claim 16 wherein the covering at least partially overlaps the webs of the at least one inner cell such that part of the covering protrudes into the at least one inner cell which is free from the covering.

22. The medical set according to claim 16 wherein a plurality of inner cells immediately adjacent in a circumferential direction of the mesh structure is covering-free.

23. The medical set according to claim 16 wherein a plurality of inner cells immediately adjacent in a longitudinal direction of the mesh structure is covering-free.

24. The medical set according to claim 16 wherein the covering extends by at most 50% over a circumference of the mesh structure.

25. The medical set according to claim 16 wherein the covering has at least 10 pores with a size of at least 15 μm.sup.2 over an area of 100,000 μm.sup.2.

26. A method for production of a medical set for treatment of an aneurysm comprising: providing a main catheter and a covering device adapted to move through the main catheter to a treatment site to cover the aneurysm, the covering device adapted to connect to a transport wire; providing a self-expandable mesh structure of the covering device, the mesh structure having webs connected together in one piece and that delimit inner cells and edge cells, wherein at a longitudinal end of the mesh structure, the edge cells form a closed edge cell ring connected to the inner cells on only one side; providing a covering of the mesh structure, the covering produced from a fabric having pores of irregular sizes; applying the covering to all inner cells using an electrospinning process; and cutting at least one inner cell free using a cutting tool, wherein the cutting tool is guided along the webs of the inner cells to be cut free so that the at least one inner cell is at least partially covering-free.

27. A medical system for treatment of an aneurysm comprising: a main catheter; and a covering device adapted to move through the main catheter to a treatment site to cover the aneurysm, the covering device adapted to connect to a transport wire, the covering device including a self-expandable mesh structure having webs connected together in one piece and that delimit inner cells and edge cells, wherein at a longitudinal end of the mesh structure, the edge cells form a closed edge cell ring connected to the inner cells on only one side and with at least one embolization means for placement in the aneurysm.

28. The medical system according to claim 27 wherein the covering device is detachably connectable to the transport wire for permanent implantation of the covering device at the treatment site and wherein in an expanded state, the covering device has open longitudinal ends.

29. The medical system according to claim 27 wherein the covering device is non-detachably connected to the transport wire for temporary implantation of the covering device at the treatment site.

30. The medical system of claim 27 further comprising: an additional catheter configured to deliver the embolization means into the aneurysm, wherein the additional catheter is relatively movable with respect to the main catheter, one of independently of or in opposition to the main catheter.

31. The medical system according to claim 27 wherein the mesh structure is provided with a covering produced from a fabric having pores of irregular sizes, and wherein at least one inner cell of the mesh structure is at least partially covering-free.

32. The medical system according to claim 31 wherein the covering is configured as an electrospun covering.

33. The medical system according to claim 31 wherein the covering ends at the webs of the inner cells which are free from the covering such that the covering does not protrude into the at least one inner cell.

34. The medical system according to claim 31 wherein the covering at least partially overlaps the webs of the at least one inner cell such that part of the covering protrudes into the at least one inner cell which is free from the covering.

35. The medical system according to claim 27 wherein the covering device is reversibly connectable to the transport wire and, in an expanded state, is open on both end sides and perfusible by blood.

Description

[0054] Exemplary embodiments of the invention will now be described with the aid of the accompanying diagrammatic drawings. In the highly simplified drawings:

[0055] FIG. 1 shows a side view of an embodiment of the medical set in accordance with the invention,

[0056] FIG. 2 shows a close-up of a preferred embodiment of a covering device of a medical set in accordance with the invention in a preferred embodiment,

[0057] FIG. 3 shows a scanning electron microscope image of a covering of a covering device of a medical set in accordance with the invention in a preferred embodiment,

[0058] FIG. 4 shows a side view of an embodiment of the medical system in accordance with the invention in the case of temporary implantation of the covering device at a treatment site, and

[0059] FIG. 5 shows a side view of a preferred embodiment of the medical system in accordance with the invention, in the case of permanent implantation of the covering device at a treatment site.

[0060] In the figures, parts with identical actions are always designated by the same reference numerals.

[0061] The medical set 2 shown in FIG. 1 is used for the treatment of aneurysms 4 and is shown in FIG. 1 in a state disposed inside a vessel 6.

[0062] The medical set 2 has a main catheter 8 as well as a covering device 12 which can be moved through the main catheter 8 to a treatment site 10. The treatment site 10 is preferably a site along the length of the vessel 6 at which the aneurysm 4 is located. The covering device 12 is used for temporary or permanent covering of the aneurysm 4, wherein the covering device 12 comprises a self-expandable mesh structure 14 produced from webs 16 (see FIG. 2). The mesh structure 14 is preferably produced from a shape memory material with a view to it being self-expandable.

[0063] Furthermore, the covering device 12 is permanently or mechanically detachably connected to a transport wire 15 which can be displaced inside the main catheter 8. The mesh structure 14 and therefore the covering device 12 when in a non-expanded state can be pushed and withdrawn through the main catheter 8 by means of this transport wire 15.

[0064] In the expanded state, the mesh structure 14 is perfusible by blood along the longitudinal axis, i.e. in and against a direction of flow F.

[0065] In particular, the mesh structure 14 is disposed inside the vessel 6 in a manner such that the covering 26 is positioned at a level with an opening 30 of the aneurysm 4 so that the latter is covered by the covering 26, wherein at the same time, a flow of blood through the vessel 6 is not stopped. The covering 26 in the exemplary embodiment of FIG. 1 is therefore substantially tubular in configuration, in particular in the manner of a hollow cylinder.

[0066] In this regard, the covering 26 is porous in configuration with large pores 28 (see FIG. 3) and perfusible, so that a supply of nutrients is ensured to the cells covered by the covering 26. Alternatively, however, the covering 26 may also be porous and not perfusible by blood.

[0067] In this regard, in particular when an embolization means 36 is being positioned (see FIG. 4) inside the aneurysm 4, the covering 26 is used so that after positioning, the embolization means 40 cannot escape from the aneurysm 4 until the blood inside the aneurysm 4 has been clotted because of the embolization means 36 and therefore the aneurysm 4 has been effectively occluded.

[0068] Particularly preferably, the covering 26 is configured as an electrospun covering 26.

[0069] As can readily be seen in FIG. 1, in addition, the medical set 2 and in particular the mesh structure 14 is provided with radiographic markers 32. The radiographic markers 32 are preferably disposed at cell tips of edge cells 20 (see FIG. 2) of the mesh structure 14. Specifically, the radiographic markers 56 are formed as radiopaque sleeves, for example produced from platinum or gold, which are crimped onto the cell tips of the edge cells 20.

[0070] FIG. 2 shows a close-up of a preferred embodiment of the covering device 12 in accordance with the invention. The webs 16 are connected together in one piece, i.e. they are monolithic, and delimit inner cells 18 as well as edge cells 20. Preferably, all of the cells, in particular inner cells 18 and edge cells 20, are respectively delimited by four webs, which together form a diamond shape. These cells which are enclosed on all sides are designated as closed cells. The edge cells 20 at one longitudinal end 22 of the mesh structure 14 form a closed edge cell ring 24 (three edge cells 20 of the edge cell ring 24 are shown encircled) in the circumferential direction which is connected to inner cells 18 on only one side.

[0071] Furthermore, the mesh structure 14 is provided with the covering 26 produced from a fabric which has irregularly sized pores 28 (see FIG. 3). At least one inner cell 18, three inner cells 18 in FIG. 1 (in the plane of the figure at the right hand edge of the mesh structure 14) are covering-free.

[0072] The construction of the covering 26 can easily be seen in the scanning electron microscope image of FIG. 3. This shows that the covering 26 has a plurality of pores 28 of irregular sizes which are respectively delimited by filaments 34. The electrospinning process forms a plurality of filaments 34 which are orientated in an irregular manner with respect to each other. In this way, the pores 28 are formed. FIG. 3 also shows that the pores 28 have a comparatively small pore size, wherein some pores 28, however, are sufficiently large to ensure perfusion, for example. Specifically, four pores 28 in FIG. 3 have been highlighted; they are more than 30 μm.sup.2 in size. The density of the pores 28 which are more than 30 μm.sup.2 in size indicates that the covering has at least 10 pores 28 of this type over an area of 100000 μm.sup.2.

[0073] FIG. 3 also shows that the filaments 34 of the covering 26 cross over each other multiple times. However, a particular feature of the electrospinning process is that in the covering 26, sites are present at which exclusively two, i.e. no more than, two filaments 34 intersect. It is clear from this that the wall thickness of the covering 26 is very small and it is therefore very flexible.

[0074] The high flexibility of the covering 26 combination with the high flexibility of the mesh structure 14 ensures that a covering device 12 can be produced which can be introduced into a (blood) vessel 6 through very small delivery catheters. In particular, delivery catheters may be used which have a size of 6 French, in particular at most 5 French, in particular at most 4 French, in particular at most 3 French, in particular at most 2 French. Specifically, the covering device in accordance with the exemplary embodiments described here may be used in catheters which have an internal diameter of at most 1.6 mm, in particular at most 1.0 mm, in particular at most 0.7 mm, in particular at most 0.4 mm.

[0075] In particularly preferred variations, the layer thickness of the covering 26 is at most 10 μm, in particular at most 8 μm, in particular at most 6 μm, in particular at most 4 μm. In this regard, at most 4, in particular at most 3, in particular at most 2 filaments 34 intersect. In general, inside the electrospun structure of tine covering 26, points of intersection are provided in which only 2 filaments 34 intersect. Preferably, the mesh structure 10 has a cross sectional diameter of between 2.5 mm and 8 mm, particular between 4.5 mm and 6 mm.

[0076] FIG. 4 shows a diagrammatically illustrated exemplary embodiment of a medical system in accordance with the invention wherein the covering device (12) has been temporarily implanted at a treatment site 10.

[0077] In this regard, the medical system comprises the aforementioned medical set 2 with the main catheter 8 as well as the covering device 12, which has the mesh structure 14 and the covering 26. The configuration of the covering 26 here corresponds to the aforementioned embodiment in accordance with FIG. 1.

[0078] Furthermore, the medical system has an embolization means 36 which, for example, is formed by a plastically deformable wire 38 or by a liquid. The embolization means 36 is placed inside the aneurysm 4 by means of an additional catheter 40 which is also part of the medical system.

[0079] In order to place the embolization means 36, in accordance with the illustrated embodiment of the medical system, the additional catheter 40 is disposed substantially parallel to, i.e. alongside the medical set 2 inside the vessel 6. In this regard, the additional catheter 40 and in particular a tip of the additional catheter 40 is “pushed” into the aneurysm 4 between a vessel wall and the covering 26 in order to place the embolization means 36 in the form of the plastically deformable wire 38 (also known as a “coil”) in it. During this and—in the event of permanent implantation—afterwards, the covering 26 prevents the embolization means 36 from escaping from the aneurysm 4, for example because of the flow of blood.

[0080] FIG. 5 shows a diagrammatic representation of an exemplary embodiment of a medical system in accordance with the invention in the case of permanent implantation of the covering device (12) at a treatment site 10.

[0081] In respect of the structural features, the medical set as well as the covering device 12 substantially correspond to the medical set described above in respect of FIG. 4. In FIG. 5, the covering device 12 is shown already implanted and expanded in the vessel 6. This means that the covering device 12 would already have been brought to the treatment site 10 by means of the transport wire 15 and detached from the transport wire 15 once there.

[0082] However, the covering device 12 of FIG. 5 has respective open longitudinal ends and is therefore substantially cylindrical, i.e. tubular in configuration, so as not to influence the flow of blood through the vessel. In the exemplary embodiment of FIG. 5, the covering device 12 therefore acts as a flow diverter.

LIST OF REFERENCE NUMERALS

[0083] 2 medical set

[0084] 4 aneurysm

[0085] 6 vessel

[0086] 8 main catheter

[0087] 10 treatment site

[0088] 12 covering device

[0089] 14 mesh structure

[0090] 15 transport wire

[0091] 16 web

[0092] 18 inner cell

[0093] 20 edge cell

[0094] 22 longitudinal end

[0095] 24 edge cell ring

[0096] 26 covering

[0097] 28 pore

[0098] 30 opening of aneurysm

[0099] 32 radiographic marker

[0100] 34 filaments

[0101] 36 embolization means

[0102] 38 wire

[0103] 40 additional catheter

[0104] F direction of flow