DE102014009920B4 - Method for making a body implant and tool therefor - Google Patents

Abstract

A method for producing a body implant for insertion into the living body, comprising the steps of: providing a tool (52; 54; 56) with a predetermined or predeterminable shape, braiding around the tool (52; 54; 56) with at least one braiding material and thereby producing one Braid (10, 10a) at least partially in the shape of the tool (52; 54; 56), performing a shaping on the braid (10), and removing the tool (52; 54; 56) from the braid (10, 10a), wherein the tool (52; 54; 56) is configured in such a way that the shape of the tool (52; 54; 56) is at least partially changeable such that the tool (52; 54; 56) can be removed when the braid ( 10, 10a) is essentially closed and / or the braid (10, 10a) at least partially envelops the tool (52; 54; 56) and / or has undercuts (12), the tool (52) at least partly as a braid or braid-like structure is formed and the tool (52) is subjected to tension for removal in order to reduce the cross-section so that removal is possible.

Description

The present invention relates to a method for manufacturing a body implant, such as a stent, a heart valve frame, a flow diverter, etc., for insertion into the living body. The invention also relates to a tool for producing a body implant.

Body implants, for example made from a nitinol mesh, are usually cylindrical or conical or a combination of both. Due to boundary conditions such as braiding angle, number of wires and geometry of the mesh as well as the required shaping processes, the possibility of variation is limited.

Conventionally, more complex forms of braids can only be produced using complex braiding algorithms or by compromising the braiding angles, as it is often not possible to expand tapered diameters to such an extent that the braid and tool can be separated without damage. It would be desirable if the design of the braids could be done with greater flexibility.

WO 2013/109 309 A1 discloses a medical device with a ball stent or a block stent and a flexible, elongated insertion catheter.

US 8 361 104 B2 describes a vascular occlusion device with an embolic mesh ribbon.

WO 2011/082 295 A2 describes stent devices and methods for their production.

US 2006/0 058 862 A1 discloses a method for producing an expandable prosthesis.

US 2014/0 058 194 A1 discloses a system for a coronary artery bypass grafting CABG, in which a braided mandrel or stent is inserted in the compressed state into a vessel in the living body and is relaxed after placement, in order to be able to establish the bypass.

The object of the invention is to provide a novel method for producing a body implant with which more flexible forms of braids can be produced.

This object is achieved by the features of the independent claims. Advantageous further developments of the invention are defined in the dependent claims.

• Bereitstellen eines Werkzeugs mit einer vorgegebenen oder vorgebbaren Gestalt,
• Umflechten des Werkzeugs mit zumindest einem Flechtmaterial und dadurch Erzeugen eines Geflechts zumindest teilweise in der Gestalt des Werkzeugs,
• Durchführen einer Formgebung an dem Geflecht und
• Entfernen des Werkzeugs von dem Geflecht, wobei das Werkzeug derart konfiguriert ist, dass die Gestalt des Werkzeugs zumindest teilweise derart veränderbar ist, dass das Werkzeug entfernt werden kann, wenn das Geflecht im wesentlichen geschlossen ist und/oder das Geflecht das Werkzeug zumindest teilweise umhüllt und/oder Hinterschneidungen aufweist,
• wobei das Werkzeug zumindest teilweise als Geflecht oder geflechtartige Struktur ausgebildet ist und zum Entfernen auf Zug beansprucht wird, um den Querschnitt so zu verringern, dass ein Entfernen ermöglicht wird.

According to one aspect, there is provided a method for manufacturing a body implant for insertion into the living body, comprising the following steps:

• Providing a tool with a predefined or predefinable shape,
• Braiding around the tool with at least one braiding material and thereby creating a braid at least partially in the shape of the tool,
• Performing a shaping on the braid and
• Removing the tool from the braid, wherein the tool is configured such that the shape of the tool is at least partially changeable in such a way that the tool can be removed when the braid is substantially closed and / or the braid at least partially envelops the tool / or has undercuts,
• wherein the tool is at least partially designed as a braid or braid-like structure and is subjected to tension for removal in order to reduce the cross section so that removal is possible.

• o Erzeugen eines Geflechts auf einem beliebig geformten Werkzeug,
• o Durchführen einer geeigneten Formgebung des Geflechts und
• o Separieren des Geflechts vom Werkzeuges.

It is therefore a process with the following steps:

• o Creation of a mesh on a tool of any shape,
• o Carrying out a suitable shaping of the braid and
• o Separating the mesh from the tool.

Thus, for example, a braid with changing diameters can be created with a flexibly selectable braiding angle and number of wires. The body implant produced can thus be optimally matched to the requirement or application. A body implant that is optimized for the individual patient, a so-called “personalized mesh”, can thus be produced in various areas of medical technology.

The term “generating a braid” is to be understood in particular as the mechanical as well as the manual production of a braid, usually braiding.

Performing the shaping is to be understood as relieving the tension that has arisen as a result of the braiding process. Once all tension has been released, the braid essentially retains its shape. For example, the shaping of nitinol is typically to be understood as a heat treatment.

The term “separating or removing the mesh from the tool” is to be understood in particular to mean that the tool is separated from the mesh.

Preferably, the step of removing the tool is performed substantially simultaneously with the shaping of the braid. This is particularly advantageous if the shaping is carried out by heat treatment and the supply of heat can change the shape of the tool.

The tool also preferably has at least one predetermined breaking point.

The tool preferably has at least one made of a plastic, such as, for example, polyvinyl alcohol or glass fiber reinforced plastic.

More preferably, the shaping of the braid includes a heat treatment.

More preferably, the braid is at least partially unbraided after shaping in order to replace the tool with another easily dissolvable and / or easily removable tool, and the braid is then braided again essentially in the same way and / or replaced by a different braiding material.

The tool preferably has a destructible section and a non-destructible section.

The tool preferably has a reusable casing which can be filled with a fluid to produce the desired shape of the tool and which is at least partially emptied for removal.

Reusable tools can, for example, be casings which are emptied when the tool is removed and can be refilled when the next braid is to be produced. However, reusable tools in the form of a mesh or a structure similar to a mesh can also be used as a tool. In this case, the separation takes place by pulling or pulling out, a cross section of the tool being reduced.

Nitinol or other common metallic wire materials could be used for reusable tools. All flexible and thin-walled materials that can withstand the respective shaping process can be used for so-called shells.

As an advantageous further development, depending on the material, shape or complexity of the mesh and the associated treatment method, it may be necessary to open the mesh. For example, these could be very fine structures that exclude the use of certain tool materials and thus cannot be braided directly on the "lost shape" tool. In this case, the braid can be opened in order to replace the original tool with another tool of essentially the same shape. The other (second) tool can consist of one material or a plurality of materials that are, for example, chemically dissolvable and / or can be melted or deformed by applying a small amount of heat. However, influencing or impairing the formed braid must be avoided.

The term “opening” is to be understood in particular to mean that the braid is disentangled again. “Opening” can be understood as a reversal or inverse process for creating a mesh. For example, a textile structure / braid can be opened by reverse braiding.

The braiding material or the nitinol wire is preferably “held in position” when it is opened. For example, ends can be fixed by means of holding devices such as grippers or wire, so that only the previous braiding process, namely the creation of the braid, is reversed or reversed. The braid is only opened until it is possible to remove the part of the tool that would not have been removed if the braid was not open.

If the direct production of the mesh requires at least a second shape, the principle of the “lost shape” can also be applied to other shaping processes. An example of the necessity would be the creation of undercuts. Ideally, combination tools are used here which consist of a destructible and a durable reusable part, the durable part preferably specifying the required final or intermediate shape.

Furthermore, the tool preferably has at least one mechanically displaceable area which can be mechanically displaced by folding over, pivoting, rotating, etc. in order to change the shape of the tool.

A vascular prosthesis, a stent graft, an occluder, a flow diverter, a coil, a heart valve frame, an AAA stent, a TAA stent (Thoracic Aortic Aneurysm) is preferably used by the method described above gastroenterological stent or a peripheral stent made. An abdominal aortic aneurysm (BAA), abdominal aortic aneurysm (AAA) or aneurysm verum aortae abdominalis is an expansion of the abdominal aorta below the exit of the renal arteries in an anterioposterior diameter to over 30 mm. Clinically, a distinction is made between asymptomatic, symptomatic and ruptured aneurysms. An asymptomatic (pain-free) aneurysm is an incidental finding. In the symptomatic aneurysm, the symptoms and in the ruptured the circulatory situation are in the foreground.

According to a further aspect, a tool for producing a body implant for insertion into the living body by at least partially braiding around the tool is provided, the tool having a shape which is at least partially changeable in such a way that the tool can be removed when a The braid generated by braiding the tool is essentially closed and / or the braid at least partially envelops the tool and / or has undercuts.

More preferably, the shape of the tool can be changed in that the tool has a reusable sheath which can be filled with a fluid to produce the desired shape of the tool and which is at least partially emptied for removal.
According to the invention, the tool is at least partially designed as a mesh or mesh-like structure.

The tool further preferably has at least one mechanically displaceable area which can be mechanically displaced by folding over, pivoting, rotating, etc. in order to change the shape of the tool.

• 1 zeigt ein Geflecht, das mittels eines geflochtenen Werkzeugs hergestellt wird.
• 2 zeigt ein aus einem Geflecht hergestelltes Körperimplantat mit Hinterschneidungen.
• 3 zeigt das Erzeugen eines Geflechts durch Umflechten eines Werkzeugs und teilweises Rückwärtsflechten zum Entfernen des Werkzeugs.
• 4 zeigt das Entfernen eines ersten Werkzeugs und Einsetzen eines anderen Werkzeugs in ein teilweise geöffnetes Geflecht.
• 5 zeigt das Fertigstellen des Geflechts aus 4.
• 6 zeigt das Erzeugen eines Geflechts und Durchführen einer Formgebung sowie das Einsetzen eines zweiten Geflechts in das erste Geflecht.

The invention will now be explained in more detail on the basis of several exemplary embodiments with reference to the accompanying drawings.

• 1 Figure 3 shows a braid made by means of a braided tool.
• 2 shows a body implant made from a braid with undercuts.
• 3 shows the creation of a braid by braiding around a tool and partially braiding backwards to remove the tool.
• 4th shows the removal of a first tool and insertion of another tool into a partially opened braid.
• 5 shows the completion of the braid 4th .
• 6th shows the creation of a braid and performing a shape as well as the insertion of a second braid into the first braid.

As in 1 shown is a braided tool 52 essentially in the form of a mesh to be produced 10 provided and the braid 10 by braiding the braided tool 52 generated. As the braid 10 is essentially closed after completion, ie only openings 14th has at opposite ends and a bulbous area in its central portion 16 having a larger diameter, the diameter of the bulbous area 16 larger than the diameter of the openings 14th is. Thus the bulbous area forms 16 an undercut to help remove the tool 52 to prevent.

Around the braided tool 52 from the finished braid 10 to remove is on opposite ends of the tool 52 Pull applied so that the braided tool 52 expands in length and the cross section is reduced. In this way, as in 1 shown is the cross section of the braided tool 52 so reduced that the cross section is smaller than that of the openings 14th is to the tool 52 from the openings 14th to be able to pull out.

Such a braided tool 52 may be re-used if the reduction in section is used to remove the tool 52 from the braid 10 takes place in the elastic range, ie the braided tool 52 resumes its original shape with the bulbous area 16 on when the pulling force is on the ends of the tool 52 is taken away. It can be with the braided tool 52 however, it can also be a tool that can only be used once if the deformation takes place outside the elastic area, so that the original shape with the bulbous area 16 through the braided tool 52 can no longer be accepted.

One such tool 52 , which can even be used in areas of undercuts and by reducing the cross-section of the finished braid 10 can also be taken from other forms of a braid 10 come into use.

An example of this is in 2 shown in a body implant 10 from a braid 10 is made that has a pair of branches with an undercut 12 having. Many complex body implant shapes can be produced in this way. A so-called personalized network can thus be made available for a patient.

The above-described way of removing a tool from a finished mesh 10 by reducing the cross-section according to the principle of the lost shape, it can also take place after a first braiding process and / or after a first shaping and / or heat treatment. For this purpose, as in the 3 and 4th initially shown is a reusable tool 54 used for braiding, around a braid 10 to manufacture.

After reverse braiding or partial opening of the braid 10 becomes the reusable tool 54 from the braid 10 removed and through a single use tool 56 replaced, as in 4th is shown. Then the braiding process is completed and the finished braid 10 is in 5 shown. The one-time use tool 56 can then from the finished braid 10 by reducing its cross-section, as in 1 is shown.

In the 3 to 5 shows the reference number 30th a well-known braiding machine with bobbins 35 to create the braid 10 .

The method described above can also be performed with that in the patent DE 10 2012 016 301 B3 described methods for producing a body implant are combined, as in 6th is shown. After an initial heat treatment, a first braid is applied 10 part of the braid 10 removed and through a second braid 10a replaced, as in 6c is shown.

The method described above is therefore particularly suitable for producing a vascular prosthesis, a stent graft, an occluder, a flow diverter, a coil, a heart valve frame, an AAA stent, a TAA stent, a gastroenterological stent or a peripheral stent.

After the braids 10 a body implant 1 can be designed very flexibly according to the method described above, complex and desired shapes can be used to create a mesh that is personalized for a patient 10 can be produced in a simple manner. The shape of the braid 10 is preferably carried out by a heat treatment in order to be in the braid 10 relieve or essentially eliminate any tension that has arisen.

However, a shape memory property can also be used, which is applied in particular to the material nitinol. A metal structure in a so-called martensite structure is created in the mesh 10 which is converted into an austenite structure by increasing the temperature by phase transformation. It is unusual for Nitinol that this conversion is reversible without the occurrence of plastic defects. The phase transition thus takes place without diffusion, i.e. without the atoms changing their places in the lattice structure. In particular, in this diffusion-free, reversible phase transformation of the austenite into the martensite structure, the atoms adopt an orderly twin arrangement through pure shear deformation.

Instead of nitinol, however, a polymer, a biodegradable polymer or tungsten can also be used. Tungsten can thereby reduce the radiopacity of the body implant 1 increase. However, so-called markers that are made of tantalum or gold, for example, can also increase the x-ray visibility.

List of reference symbols

1

Body implant

10, 10a

Braid

12

Undercut

14th

opening

16

bulbous area

30th

Braiding machine

35

Clapper

52

braided tool

54

reusable tool

56

single use tool

Claims (14)

A method for producing a body implant for insertion in the living body, comprising the steps of: providing a tool (52; 54; 56) with a predetermined or predeterminable shape, braiding around the tool (52; 54; 56) with at least one braiding material and thereby producing one Braid (10, 10a) at least partially in the shape of the tool (52; 54; 56), performing a shaping on the braid (10), and removing the tool (52; 54; 56) from the braid (10, 10a) , wherein the tool (52; 54; 56) is configured such that the shape of the tool (52; 54; 56) is at least partially changeable in such a way that the tool (52; 54; 56) can be removed when the braid (10, 10a) is essentially closed and / or the braid (10, 10a) the Tool (52; 54; 56) at least partially enveloped and / or undercuts (12), the tool (52) being at least partially designed as a braid or braid-like structure and the tool (52) being subjected to tension for removal, around the To reduce the cross-section so that removal is possible. Procedure according to Claim 1 wherein the step of removing the tool (52; 54; 56) is performed substantially simultaneously with the shaping of the braid (10). Method according to one of the preceding claims, wherein the tool (56) has at least one predetermined breaking point. Method according to one of the preceding claims, wherein the tool (52; 54; 56) has at least one made of plastic, preferably polyvinyl alcohol or glass fiber reinforced plastic. Method according to one of the preceding claims, wherein the shaping of the braid (10) includes a heat treatment. Method according to one of the preceding claims, wherein the braid (10) is at least partially unbraided after shaping in order to replace the tool (54) with another easily dissolvable and / or easily removable tool (52, 56), and the braid ( 10) is then braided again essentially in the same way and / or is replaced by another braiding material (10a). Method according to one of the preceding claims, wherein the tool (52; 54; 56) has a destructible section and a non-destructible section. Method according to one of the preceding claims, wherein the tool (54) has a reusable sheath which can be filled with a fluid to produce the desired shape of the tool and which is at least partially emptied for removal. Method according to one of the preceding claims, wherein the tool (52; 54; 56) has at least one mechanically displaceable area which is mechanically displaceable by folding over, pivoting, rotating, etc. in order to match the shape of the tool (52; 54; 56) change. Method according to one of the preceding claims, wherein a vascular prosthesis, a stent graft, an occluder, a flow diverter, a coil, a heart valve frame, an AAA stent, a TAA stent, a gastroenterological stent or a peripheral stent is produced. Tool for producing a body implant for insertion into the living body by at least partially braiding around the tool (52; 54; 56), the tool (52; 54; 56) having a shape which is at least partially changeable in such a way that the tool ( 52; 54; 56) can be removed when a braid (10, 10a) produced by braiding around the tool (52; 54; 56) is essentially closed and / or the braid (10, 10a) supports the tool (52; 54 ; 56) at least partially enveloped and / or undercuts (12), the tool (52) being at least partially designed as a braid or braid-like structure and the tool (52) for removal being able to be subjected to tension in order to reduce the cross section to allow removal. Tool after Claim 11 , wherein the tool (56) has at least one predetermined breaking point. Tool after Claim 11 wherein the shape of the tool (56) can be changed in that the tool (54) has a reusable sheath which can be filled with a fluid to produce the desired shape of the tool and which is at least partially emptied for removal. Tool after Claim 11 which has at least one mechanically displaceable area which can be mechanically displaced by folding over, pivoting, rotating, etc. in order to change the shape of the tool (52; 54; 56).

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