DE102014009920A1 - Method of making a body implant and tool therefor - Google Patents

Abstract

The invention relates to a method for producing a body implant with the following steps:
Providing a tool with a predetermined or predeterminable shape,
Braiding 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 (52; 54; 56) is at least partially variable such that the tool (52; 54; 56) can be removed when the braid in is substantially closed and / or the mesh at least partially envelops the tool and / or undercuts.

Description

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

For example, body implants made of nitinol mesh are typically cylindrical or conical or a combination of both. Due to boundary conditions such. B. braid angle, number of wires and geometry of the braid and the necessary shaping processes, the possibility of variation is limited.

Conventionally, more complex forms of braids can only be produced by elaborate braiding algorithms or by braiding tradeoffs, since it is often not possible to stretch tapered diameters to such an extent that damage-free separation of braid and tool is possible. It would be desirable if the design of the braids could be made with greater flexibility.

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 solved by the features of the independent claims. Advantageous developments of the invention are defined in the dependent claims.

According to one aspect, there is provided a method of manufacturing a body implant comprising the steps of:
Providing a tool with a predetermined or predeterminable shape,
Braiding 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 so variable that the tool can be removed when the braid is substantially closed and / or the braid encases the tool at least partially and / or undercuts.

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

It is therefore a procedure with the steps:

• Creating a braid on an arbitrarily shaped tool,
• - Performing a suitable shaping of the mesh, and
• - Separate the braid from the tool.

Thus, for example, a mesh with changing diameters can be produced with flexibly selectable braiding angle and number of wires. The generated body implant can thus be optimally adapted to the requirement or the application. Thus, in various fields of medical technology, a body implant optimized for the individual patient, a so-called "personalized braid", can be produced.

The term "producing a braid" is to be understood as meaning, in particular, the mechanical as well as the manual production of a braiding, usually braiding.

By performing the shaping is meant a reduction of the stresses that have arisen as a result of the braiding process. When all stresses have been removed, the braid essentially retains its shape. For example, for Nitinol the shaping is typically to be understood as a heat treatment.

The term "separating or removing the braid from the tool" is understood in particular to mean that the tool is separated from the braid. Removal may preferably be carried out by melting due to heat, breaking, dissolution in or by suitable chemical substances, including water and by forming the tool. As a result, the tool is at least damaged and usually can not be reused. In this context, one speaks of a tool that can be used once or of the principle of a "lost form".

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

More preferably, the shape of the tool is changed by the tool, for example, melts, breaks or dissolves.

Advantageous are tools that destroy themselves during the molding process, for example, due to high temperatures or temperature differences. In this case, the destruction may only take place after the shaping has taken place or the shaping process should run according to plan.

More preferably, the tool has at least one predetermined breaking point.

Preferably, the tool comprises at least one of a wax, resin, plastic such as polyvinyl alcohol, foam, elastomer, glass fiber reinforced plastic, pulp, gypsum, salt, sugar, glue, glass, sand. For example, glass, salts and sand compounds may be suitable for self-destruction.

More preferably, the shaping on the mesh includes a heat treatment.

More preferably, after forming, the braid is at least partially unbonded to replace the tool with another easily dissolvable and / or easily removable tool, and the braid is then braided again in substantially the same manner and / or replaced with another braiding material ,

Preferably, the tool has a destructible portion and a non-destructible portion.

Preferably, the tool has a reusable sheath which can be filled with a fluid to produce the desired shape of the tool and at least partially emptied for removal.

Reusable tools may be, for example, casings that are emptied when removing the tool and can be refilled at a next mesh to be produced. However, reusable tools in the form of a braid or a structure similar to a braid can also be used structured as a tool. In this case, the separation is carried out by pulling or pulling, wherein preferably a cross section of the tool is reduced.

Nitinol or other common metallic wire materials could be used for reusable tools. For so-called casings, all flexible and thin-walled executable materials can be used which can withstand the respective shaping process.

More preferably, the tool is at least partially formed as a braid or mesh-like structure and is claimed for removal to train to reduce the cross section so that a removal is made possible.

As an advantageous development, depending on the material, shape or complexity of the braid and the associated treatment method, an opening of the braid may be required. For example, these could be very fine structures that exclude the use of certain tooling materials and thus can not be braided directly on the "lost shape" tool.

In this case, the braid can be opened to replace the original tool with another substantially same shape tool. In this case, the other (second) tool consist of one or more materials that are, for example, chemically dissolvable and / or melted or deformed by low heat input. However, an influence or impairment of the formed braid must be avoided.

The term "opening" is to be understood in particular that the braid is unbound again. An "open" can be understood as a reversal or inverse process for creating a mesh. For example, a textile structure / braid can be opened by braiding it backwards.

Preferably, upon opening, the braiding material or nitinol wire is "held in position". 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. The mesh is only opened until it is possible to remove the part of the tool that would not be removable if the mesh was not open.

If the direct generation of the mesh requires at least second shaping, the principle of the "lost form" can also be applied to other shaping processes. An example of the need would be to create undercuts. Ideally, this combination tools are used, which consist of a destructible and a durable reusable part, wherein the durable part preferably specifies the required final or intermediate shape.

More preferably, the tool has at least one mechanically displaceable region, which is mechanically displaceable by folding, pivoting, turning, etc., in order to change the shape of the tool.

Preferably, by the method described above, 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), a gastronenterologic stent or a peripheral stent. Abdominal aortic aneurysm (BAA), abdominal aortic aneurysm (AAA) or abdominal aortic aneurysm is considered to be an enlargement of the abdominal aorta below the exit of the renal arteries in the anterior-posterior diameter to over 30 mm. Clinically, a distinction is made between asymptomatic, symptomatic and ruptured aneurysms. The asymptomatic (painless) aneurysm is a chance finding. Symptomatic aneurysm is dominated by symptoms and ruptured by circulatory conditions.

According to a further aspect, a tool for producing a body implant is provided by at least partially braiding the tool, wherein the tool has a shape that is at least partially variable such that the tool can be removed if a braid created by braiding the tool is substantially closed and / or the braid, the tool at least partially wrapped and / or undercuts.

Preferably, the shape of the tool is variable by the tool melts, breaks and / or dissolves and / or the tool has at least one predetermined breaking point.

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

Preferably, the tool is at least partially formed as a braid or mesh-like structure.

More preferably, the tool has at least one mechanically displaceable region, which is mechanically displaceable by folding, pivoting, turning, etc., in order to change the shape of the tool.

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

1 shows a braid that is made by means of a braided tool.

2 shows a made of a braid body implant with undercuts.

3 Figure 3 shows the creation of a braid by braiding a tool and partially braiding it back to remove the tool.

4 shows the removal of a first tool and insertion of another tool in a partially opened braid.

5 shows completion of the braid 4 ,

6 shows the creation of a braid and performing a shaping and the insertion of a second braid in the first braid.

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

To the braided tool 52 from the finished braid 10 to remove it is on the opposite ends of the tool 52 Train exercised so that the braided tool 52 extends in length and the cross-section is reduced. In this way, as in 1 shown is the cross section of the braided tool 52 reduced so that the cross section is smaller than that of the openings 14 is to the tool 52 from the openings 14 to be able to pull out.

Such a braided tool 52 may be reused if the reduction in cross-section to remove the tool 52 out of the network 10 takes place in the elastic region, ie the braided tool 52 takes back the original shape with the bulbous area 16 when the pulling force on the ends of the tool 52 is taken away. It can be with the braided tool 52 but also act as a single-use tool, when the deformation takes place outside the elastic range, so that the original shape with the bulbous area 16 through the braided tool 52 can no longer be accepted.

Such a tool 52 , which can be applied even in areas of undercuts and by a cross-sectional reduction the finished braid 10 can also be taken from other shapes of a braid 10 to apply.

An example of this is in 2 shown in a body implant 10 from a network 10 made a couple of branches with an undercut 12 having. In this way, many complex shapes of a body implant can be produced. It can thus be provided a so-called personalized braid for a patient.

However, the invention is not limited to the use of a braided tool 52 limited, but can also be performed with tools that can be resolved, for example by heat. Examples include wax, resin and plastics such as polyphenyl alcohol. In this case, a tool from the undercuts 12 or a bulbous area 16 be removed by dissolving the tool. For this purpose, for example, heat is applied to bring the tool to melt or dissolve.

Another way to remove the tool from a manufactured braid 10 is to break the tool, dissolve and / or provided with a predetermined breaking point.

The above-described way of removing a tool from a finished mesh 10 By reducing the cross-section, melting, breaking or dissolving according to the lost-mold principle, 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 4 shown is first a reusable tool 54 applied to braiding to a braid 10 manufacture.

After backward weaving or partial opening of the braid 10 becomes the reusable tool 54 out of the network 10 taken and by a one-time usable tool 56 replaced, as in 4 is shown. Thereafter, the braiding process is completed and the finished braid 10 is in 5 shown. The unique tool 56 can then from the finished braid 10 can be taken by reducing its cross-section, as in 1 is shown, or the one-time use tool 56 by melting, breaking or dissolving from the mesh 10 is removed.

In the 3 to 5 shows the reference numeral 30 a well-known braiding machine with bobbins 35 for creating the mesh 10 ,

The method described above can also be used with that in the patent DE 10 2012 016 301 B3 described method for producing a body implant, as in 6 is shown. In this case, after a first heat treatment on a first braid 10 a part of the mesh 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, stent graft, occluder, flow diverter, coil, heart valve frame, AAA stent, TAA stent, gastroenterological stent or peripheral stent.

After the braids 10 a body implant 1 can be made very flexible according to the method described above, complex and desired shapes for generating a personalized for a patient mesh 10 be made in a simple way. The shape of the mesh 10 is preferably performed by a heat treatment to be in the braid 10 reduce or essentially eliminate the resulting stresses.

However, it is also possible to apply a shape memory property, which is used in particular on the material Nitinol. In this case, a metal structure in a so-called Martensitstruktur in the braid 10 provided by increasing the temperature by phase transformation into an austenite structure. It is for Nitinol. It is extraordinary that this transformation is reversible without any plastic defects. The phase transformation thus takes place without diffusion, that is, without the atoms changing places in the lattice structure. In particular, in this diffusionless reversible phase transformation of the austenite into the martensite structure, the atoms adopt an ordered twin arrangement through pure shear deformation.

However, instead of nitinol, a polymer, a biodegradable polymer or tungsten may also be used. In this case, tungsten can the radiopacity of the body implant 1 increase. However, so-called markers can increase the radiopacity, which are made of tantalum or gold, for example.

LIST OF REFERENCE NUMBERS

1

body implant

10, 10a

weave

12

undercut

14

opening

16

bulbous area

30

braiding

35

tongue

52

braided tool

54

reusable tool

56

single-use tool

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012016301 B3 [0053]

Claims (15)

Method for producing a body implant comprising the steps of: providing a tool ( 52 ; 54 ; 56 ) with a predetermined or predefinable shape, braiding the tool ( 52 ; 54 ; 56 ) with at least one braiding material and thereby creating a 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 ) of the mesh ( 10 . 10a ), the tool ( 52 ; 54 ; 56 ) is configured such that the shape of the tool ( 52 ; 54 ; 56 ) is at least partially variable such that the tool ( 52 ; 54 ; 56 ) can be removed when the braid ( 10 . 10a ) is substantially closed and / or the braid ( 10 . 10a ) the tool ( 52 ; 54 ; 56 ) at least partially enveloped and / or undercuts ( 12 ) having. The method of claim 1, wherein the step of removing the tool ( 52 ; 54 ; 56 ) substantially simultaneously with the shaping on the braid ( 10 ) is carried out. Method according to one of the preceding claims, wherein the shape of the tool ( 56 ) is changed by the tool ( 56 ) melts, breaks and / or dissolves and / or the tool ( 56 ) has at least one predetermined breaking point. Method according to one of the preceding claims, wherein the tool ( 52 ; 54 ; 56 ) at least one of a wax, resin, plastic preferably polyvinyl alcohol, foam, elastomer, glass fiber reinforced plastic, pulp, gypsum, salt, sugar, glue, glass, sand. Method according to one of the preceding claims, wherein the shaping on the braid ( 10 ) includes a heat treatment. Method according to one of the preceding claims, wherein the braid ( 10 ) is at least partially unbound after shaping in order to 54 ) by another easily dissolvable and / or easily removable tool ( 52 . 56 ), and the braid ( 10 ) is then braided again in substantially the same way and / or by another braiding material ( 10a ) is replaced. Method according to one of the preceding claims, wherein the tool ( 52 ; 54 ; 56 ) has a destructible portion and a non-destructible portion. 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 at least partially emptied for removal. Method according to one of the preceding claims, wherein the tool ( 52 ) is at least partially formed as a braid or mesh-like structure and the tool ( 52 ) is subjected to tensile removal to reduce the cross-section to permit removal. Method according to one of the preceding claims, wherein the tool ( 52 ; 54 ; 56 ) has at least one mechanically displaceable region, which is mechanically displaceable by folding, pivoting, turning, etc., in order to increase the shape of the tool ( 52 ; 54 ; 56 ) to change. The method of any 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 gastronenterologic stent or a peripheral stent is made. Tool for producing a body implant by at least partially braiding the tool ( 52 ; 54 ; 56 ), the tool ( 52 ; 54 ; 56 ) has a shape that is at least partially variable such that the tool ( 52 ; 54 ; 56 ) can be removed if a by braiding the tool ( 52 ; 54 ; 56 ) created network ( 10 . 10a ) is substantially closed and / or the braid ( 10 . 10a ) the tool ( 52 ; 54 ; 56 ) at least partially enveloped and / or undercuts ( 12 ) having. Tool according to claim 12, wherein the shape of the tool ( 56 ) is changeable by the tool ( 56 ) melts, breaks and / or dissolves and / or the tool ( 56 ) has at least one predetermined breaking point. Tool according to claim 12, wherein the shape of the tool ( 56 ) is changeable by the tool ( 54 ) has a reusable sheath which can be filled with a fluid to produce the desired shape of the tool and at least partially emptied for removal. Tool according to claim 12, which is at least partially formed as a braid or braid-like structure and / or at least one mechanically displaceable region which by folding, pivoting, rotating, etc. mechanically is displaceable to the shape of the tool ( 52 ; 54 ; 56 ) to change.

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