DE102013112319A1 - Holding device for the body-external transmitter unit - Google Patents

Abstract

Holding device for an off-axis unit, wherein the holding device comprises a first portion, which is at least partially locatable in or under the skin, and a second portion which can be arranged extracorporeally on the first portion, and wherein the second portion means for releasable and recoverable Has fixation of the body-external unit.

Description

The present invention relates to a holding device for an out-of-body unit, wherein the unit is in particular designed to supply energy to a medical implant in the human or animal body and / or to communicate with the implant.

In the case of medical implants which communicate telemetrically through the skin with an entity external to the body and are supplied with electrical energy by this unit, the question arises as to how the energy provider and communication partner, ie the entity external to the body, can be spatially aligned with the implant to obtain a sufficiently good and reproducible coupling for the power supply and data communication. In the case of cochlear implants that are inductively energized via an alternating magnetic field, a combination of magnets may be used for alignment, with one magnet being part of the implant and the other magnet part of the out-of-body unit. The body-external unit automatically "snaps" to the intended location via the magnetic coupling and thus aligns reproducibly with the implant. As a result, a comfortable release of the external unit, for example, by the patient himself possible and on the other hand, a injury-free detachment of the external unit in case of excessive forces ensured. A major problem today and increasingly in the future is that the magnet associated with the implant makes the use of increasingly popular magnetic resonance imaging (MRI) as imaging difficult or impossible. The problem arises from the fact that MRI uses strong magnetic fields that can cause inadmissibly high forces on the magnet of the implant. The maximum permissible forces are defined by international standards, eg EN 45002-2-3 , given.

Another problem arises when used in animals whose skin is significantly thicker than that of humans, because the magnetic attraction between the magnets decreases exponentially with increasing distance. This has the consequence that the liability of the external unit in moving animals for safe data communication and power supply can only be realized by magnets with very high attraction and thus large dimensions.

So far, the positioning components for the off-axis unit are implanted. Some implants use magnets that do not allow an MRI scan with current magnetic field strengths of 1.5 Tesla or 3 Tesla. Some manufacturers of cochlear implants offer as a solution to an upcoming MRI scan to surgically remove the magnet and reimplant it after an MRI scan.

This procedure thus requires surgical interventions that are stressful for the patient, risky and not least time-consuming and costly. Also, damage to the parts by the interventions are not excluded. If, on the other hand, the magnet remains in the body, MRI imaging can be disturbed or even impossible, as explained above.

In magnetic coupling with a single magnet, there is no alignment between the external unit and the implant with respect to the angle of rotation. By a plurality of holding devices a defined angular orientation is ensured.

Especially in animals, the positioning components for the body-external unit are either not detachable or detachable with freedom of movement between external unit and implant arranged here the external unit is attached with straps or a harness. Even the sewing of the external unit on the skin is possible. A magnet in the implant as well as the cochlear implants is also a variant used. The disadvantages of these solutions include that straps or harnesses do not offer safe protection against moving the external unit by several centimeters. In a magnetic coupling, the large distance between the magnet in the implant and the external unit results in an exponentially decreasing force of attraction between the magnets due to the stronger skin. For measurements over a longer period, the coat must be shaved under the external unit, for which it must be removed. The re-sewing means for the animal apart from the additional anesthesia regularly an increased risk of infection.

The object of the invention is to provide a fastening device or an arrangement for a body-external unit, which provides a reliable fixation possibility and yet allows the use of MRI techniques.

This object is achieved by a device according to claim 1 or an arrangement for fixing an off-body unit on the skin of a living being according to claim 10. Advantageous developments of the invention are defined in the further claims.

In accordance with the invention, therefore, a holding device is provided for an entity external of the body, wherein the holding device has a first section that is at least partially in or under the skin can be arranged, and a second portion which can be arranged extracorporeally on the first portion, and wherein the second portion comprises means for releasably and restorable fixation of the body-external unit.

It is advantageous if the means on the second section are designed to be extracorporeal and extracorporeal removable.

The means may comprise at least one threaded portion.

The means may also comprise at least one magnetic, in particular permanent-magnetic part, which can cooperate with the body-external unit.

Also, the means may comprise at least one push-button part which can cooperate with the body-external unit.

The first portion and / or the second portion may be at least partially tubular.

The first section and the second section may comprise a tubular sheath and a magnetic, in particular permanent magnetic, core (within the sheath).

The first section can have means, in particular openings, which serve to reinforce the fixed applicability or fixability of the first section and are designed in particular for sewing or riveting.

The second section may comprise a thickened area, which contributes to the fixation of the holding device in the implantation position.

The invention further comprises an arrangement for fixing an off-body unit on the skin of a living being, in particular in the vicinity of an implant, wherein at least one holding device according to this invention is provided as described above.

It is particularly advantageous if at least two holding devices are provided according to this invention.

It is also advantageous if a thickened region is provided, which is configured to cooperate in the fixing position of the external unit with the skin and / or with the implant to produce a positive connection of the external unit with the skin.

The thickened area can be designed frame-shaped. Other embodiments of the invention may include the following features. At least two holding devices can be arranged on edge regions of the body-external unit.

In the holding device according to the invention, the first portion may be partially locatable under the skin.

In the holding device according to the invention, at least the first section can be made biocompatible.

The first section may have a planar area which serves as a fixing base.

The first section can also be partially arranged under the skin.

There may be provided extension elements for adaptation to different skin strengths.

The body-external unit can be designed for, in particular wireless, power supply and / or communication with an implant.

The invention provides a detachable attachment of the external unit through different extracorporeal coupling elements which are screwed into implanted first sections of biocompatible material. Before an MRI examination, the coupling elements can be unscrewed, as a result of which the magnetic fields occurring during the examination no longer have any points of attack. After completion of the MRI examination, the coupling elements can then be screwed on again.

Thus, the invention described herein demonstrates new approaches to the magnetic or mechanical locking of external units to the implant, which allow MRI examinations to be performed without special consideration of the magnets used. In addition, the invention provides a way of releasably or permanently attaching an external unit to the body surface in animals and humans irrespective of the distance between the implant and the external unit.

New is therefore the fixation by a fastening device that is only partially implanted. The (permanently) implanted part ensures a firm local reference to the implant. The non-implanted part realizes the detachable or permanent connection of the external unit.

All advantages arise from the overcome disadvantages, as described in the prior art. In essence, it should be noted here:
The surgical burden on the patient in the case of an MRI scan is eliminated and there is the possibility of immediate MRI scan without waiting for surgical pretreatment.

Especially in animals, a long-term use of the body-external unit - and thus also of the implant - due to the reliable releasable attachment opens.

The invention and exemplary embodiments will be described in more detail with reference to the drawing. In the drawing show:

1 a first embodiment of the invention;

2 a second embodiment of the invention;

3 an arrangement on the body using holding devices according to the first embodiment;

4 an arrangement on the body using holding devices according to the second embodiment;

5 another arrangement on the body using holding devices according to the first embodiment; and

6A . 6B further embodiments of the invention.

1 shows the first embodiment of the holding device according to the invention. The first paragraph 1 the holding device is by a base plate 4 and a rod perpendicular thereto 2 with a female thread section 2a educated. The second section with means for detachable and recoverable fixation of a body-external unit 8th is by a screw 13 with external thread section 7 educated. Internally threaded portion 2a and male threaded section 7 correspond to each other, so that the two sections can be screwed together. In the base plate 4 can also have at least one opening 3 be provided, whereby the ingrowth of the base plate 4 is improved with the surrounding tissue. Such an opening 3 also allows sewing to the fabric. At least the first section 1 is made of biocompatible material or coated with such material.

The method for fixing the holding devices runs as follows. Near the implant 10 that in humans usually occurs within the tissue 12 is located, the base plate 4 implanted, in or under the skin 11 or between the skin 11 and underlying tissue 12 , The rod 2 protrudes above the skin 11 out. The external unit 10 is by means of the second section, here the screw 13 with external thread section 7 , with the first section 1 So the staff 2 screwed. This is external unit 8th stationary and permanent, but at any time without surgical intervention detachably connected to the patient or to the animal. Lifting or dropping the external unit 8th is without loosening the screw connection 2a . 7 not possible.

In particular, if the retaining element is used in an animal, due to the stronger skin, the holding device can be dependent on the positioning of the implant 10 also in the skin 11 instead of being used below.

In the embodiment of the holding device according to the invention according to 2 is the first section 1 exactly as configured as in the first embodiment. The means of the second section comprise a permanent magnet 6 , This permanent magnet 6 is by means of coupling element 5 and threaded section 7 with the wand 2 of the first section 1 screwed. The permanent magnet 6 may be coated with a biocompatible coating as a wrapper. Instead of the permanent magnetic core (or soul) 6 For example, a non-permanent magnetic core (or core) of ferromagnetic material may also be used.

The use of these fixtures is done as follows. At least one holding device is implanted in the vicinity of the implant, as already described in connection with the first embodiment. Their base plate 4 has one or more holes 3 , which improves the intergrowth with the surrounding tissue. The holes 3 additionally allow stitching to the fabric. In the bar 2 of the section 1 After implantation, the magnetic coupling element 5 . 6 screwed. The rod 2 is in its length to the thickness of the skin 11 adapted or can by extension essays 19 , which can be different lengths, be adapted to different skin strengths. The extension attachments 19 can in the bar 2 be plugged or screwed. The external unit 8th has to the magnets 6 corresponding magnets 13 , causing the external unit 8th is locked in place correct. Magnetic couplings are used, on the one hand to allow a comfortable release of the external unit, for example, by the patient himself and on the other hand an injury-free detachment of the external unit to ensure the occurrence of excessive forces. If, for example, an MRT examination is pending, the fixing means, ie the magnetic coupling element 5 . 6 from the first section 1 be unscrewed. Furthermore, the staff can 2 if necessary. After the MRI scan, these parts can be reattached without requiring surgery.

3 shows the inventive arrangement for fixing an out-of-body unit, the body-external unit and the position of the implant on the human or animal body using a plurality of holding devices according to the first embodiment. The first section of each holding device is in or between the skin 11 and the underlying tissue 12 implanted. The external unit 8th is by means of fixing 13 with the first section 1 screwed and fixed over the implant in a defined local relationship to the implant permanently fixed position but releasably. In 3 an attachment by means of only two holding devices is shown. However, more holding devices can be provided, for example, in the case of a quadrangular external unit at each corner region.

4 shows the inventive arrangement for fixing an off-axis unit, the off-axis unit and the position of the implant on the human or animal body using a plurality of holding devices according to the second embodiment. The first section of each holding device is placed between skin 11 and underlying tissue 12 implanted. The magnetic coupling elements 5 . 6 fix the external unit 8th with their embedded magnets 9 above the implant 10 , The external unit 8th in other words, permanently fixed in position but releasably fixed over the implant in a defined local relationship to the implant. Again, more than two holding devices can be provided.

Of course, holding devices of various embodiments can be combined to fix an external unit.

5 shows an application of the invention, which allows a particularly fixed position fixation of the external unit. This is where the implant becomes 10 so under the skin 11 used that to bulge it 18 of the skin 11 above the implant 10 or the tissue comes. This bulge 18 forms together with a depression in the bottom of the external unit 8th or one on the external unit 8th attached frame 17 a form fit, in addition to the attachment by the Haltevorrichtrungen invention additional protection against dislocation between implant 10 and external unit 8th offers. The depression or the frame 17 is on the skin 11 facing side of the external unit 8th arranged (in mounting position). The holding devices engage outside the recess or the frame 17 at the external unit 8th at.

This application can be formed with any holding device according to the invention. The frame 17 may also be part of the holding device or the holding devices.

In a further embodiment, a push-button system is provided as a fixing means. One part of the push-button system is arranged on the holding device on the second section, ie in the assembly position outside the body, the other part on the body-external unit 8th , The push-button system can then also be actuated body-external.

Furthermore, the holding device according to the invention can comprise adjusting means with which, after implantation of the first section, an even more precise alignment of the external unit is made possible without the first section having to be displaced in the skin. This is advantageous when the relative positioning of external unit and implant or first sections e.g. due to changes in the skin or the tissue over time, something changed or accurate positioning of the first sections is not possible. Furthermore, the orientation can then also be optimized in situ without surgical intervention, depending on the transmission properties of the external unit or of the implant.

The embodiments according to 6A , B are formed by rod, arc, ring or spiral structures. 6A shows top views of the skin surface, 6B shows a sectional view perpendicular to the skin surface. These structures have circular or annular (tubular) cross section. The structures comprise a magnetic, in particular ferromagnetic, core and a shell of biocompatible plastic or metal. The structures can be completely rigid or flexible or contain flexible sections. In the case of flexible structures, the permanent magnetic or ferromagnetic core is divided into at least 2 individual cores or it also consists of flexible material such as medical silicone with embedded magnetic components such as ferromagnetic particles. These structures are threaded through the skin, creating a skin ridge at each puncture site 16 arises. The first paragraph 1 is therefore formed by that part of the structure that after threading of the skin 11 is covered, ie in or under the skin 11 lies. The second section is through the uncovered, ie exposed part 14 the structure is formed. The fixing means for the external unit 8th are formed by the magnetic, in particular ferromagnetic core. The two ends of the structure can be finished with a closure piece 15 , which is attached after threading and prevents unwanted unthreading be provided. This final piece 15 is a thickened area, which thus contributes in the implantation position of the holding device for fixing. The end piece is located above the skin 11 ,

The body-external unit 8th has at least one embedded magnet, which sticks to the magnetic structure. The magnetic holding device fixes the external unit 8th with their embedded magnet 9 above the implant 10 which is in the underlying tissue 12 is implanted. The structure can be threaded out of the skin as a whole, for example for MRI examinations. In any case, because the sites where the structures pierce the skin rapidly scar, the removal and subsequent reinsertion of the structures at the same sites is not surgical intervention.

Instead of the magnetic or ferromagnetic fixative on the external unit 8th may also be provided other fixing means, for example, purely mechanical hooks or the like.

In all embodiments, the off-field unit may be a transmitter unit as described in the introduction. The implant may be a probe for receiving and transmitting neural signals and / or for neuronal stimulation. The probe may in particular be implanted in the brain. In the case of such probes, as stated at the outset, a particularly accurate and permanent positioning of the implanted probe to an entity external to the body occurs.

As the material for the holding device, for example, polyamide (PA12) is used. The holding device can be produced by laser sintering, other 3D printing or injection molding. In addition, the production by milling, turning, grinding, drilling, forging or eroding the massive starting material is possible. For holders made of silicone or with silicone sheath, the production can be done in a casting process.

Other possible materials for the implant itself or for the implant shell are titanium or titanium alloys and stainless steel as well as MP35N as metals. As non-metals come into question, for example. Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyurethane (PUR), polysiloxanes, polyether ketone (PEEK) and silicone. For the permanent magnetic parts, e.g. Neodymium and ferrite.

LIST OF REFERENCE NUMBERS

1

 first section

2

 Rod

2a

 Internally threaded portion

3

 Opening, bore

4

 baseplate

5

 Magnetic coupling element

6

 magnet

7

 Externally threaded section

8th

 external unit

9

 magnet

10

 implant

11

 skin

12

 tissue

13

 Fixing element, screw

14

 magnetic section

15

 termination element

16

 Hautwulst

17

 frame

18

 bulge

19

 extension element

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 non-patent literature

• EN 45002-2-3 [0002]

Claims (14)

Holding device for an out-of-body unit ( 8th ), wherein the holding device has a first section ( 1 ), at least partially in or under the skin ( 11 ), and a second portion, which can be arranged extracorporeally on the first portion, and wherein the second portion comprises means ( 6 . 7 . 13 ) for detachable and recoverable fixation of the body-external unit ( 8th ) having. Holding device according to claim 1, wherein the means on the second portion are arranged extracorporeally arranged and removable extracorporeal. Holding device according to claim 2 or 3, wherein the means comprise at least one threaded portion ( 7 ). Holding device according to one of claims 2 to 4, wherein the means ( 6 . 7 . 13 ) at least one magnetic, in particular permanent magnetic part ( 6 ), which can interact with the off-board unit. Holding device according to one of claims 2 to 5, wherein the means ( 6 . 7 . 13 ) comprise at least one push-button part which can cooperate with the body-external unit. Holding device according to one of the preceding claims, wherein the first section ( 1 ) and / or the second section is at least partially tubular. Holding device according to one of the preceding claims, wherein the first section ( 1 ) and the second portion have a tubular sheath and a magnetic, in particular permanent magnetic soul. Holding device according to one of the preceding claims, wherein the first section ( 1 ) Means, in particular openings ( 3 ), which serve to reinforce the fixed location of the first portion and are designed in particular for sewing or riveting. Holding device according to one of the preceding claims, wherein the second portion has a thickened region ( 15 ), which contributes to the fixation of the holding device in the implantation position. Arrangement for fixing an out-of-body unit ( 8th ) on the skin ( 11 ) of a living being, in particular in the vicinity of an implant ( 10 ), wherein at least one holding device according to one of the preceding claims is provided. Arrangement according to claim 10, wherein at least two holding devices are provided according to the previous claims. Arrangement according to claim 10 or 11, wherein a thickened region ( 17 ) is provided, which is configured in the fixing position of the body-external unit ( 8th ) with the skin ( 11 ) and / or with the implant ( 10 ) to achieve a positive fit of the external entity ( 8th ) with the skin ( 11 ). Arrangement according to claim 12, wherein the area ( 17 ) is designed frame-shaped. Arrangement according to one of claims 10 to 13, wherein at least two holding devices at edge regions of the body-external unit ( 8th ) can be arranged.

Images