WO2000008895A2

WO2000008895A2 - Method for producing an adjustment part to be introduced into an organic cavity of the human body

Info

Publication number: WO2000008895A2
Application number: PCT/EP1999/005086
Authority: WO
Inventors: Rainer Schmidt
Original assignee: Audio Consulting Gesellschaft Für Strategisches Marketing Mbh
Priority date: 1998-08-01
Filing date: 1999-07-16
Publication date: 2000-02-17
Also published as: WO2000008895A3; EP1021932A2; CA2305241A1; DE19834849A1; AU5411699A

Abstract

In order to carry out an otoplasty for IO- and HdO-type audio prostheses or for a nose adjustment part, a hollow body in the shape of a truncated cone is provided that tapers towards the proximal end and that comprises a peripheral wall (12) made of a plastic light-curable material capable of deformation. The peripheral wall (12) is connected at its distal end by a removable closure plate (20) providing a tight seal. A flexible tube (22) extends inside the tightly sealed hollow body (10). After insertion of the hollow body into the ear, the flexible tube is used for inflating said hollow body until the peripheral wall (12) tightly conforms the surface of the auditory canal. At this step, the peripheral wall is at least partially reinforced by the action of light so that the hollow body (10) keeps its expanded shape even after eliminating the inner over-pressure. The closure plate (20) is then removed and the peripheral wall (12) is optionally permanently cured. The otoplasty thus obtained is used for receiving a auditory prosthesis module which is placed within the ear and which comprises a base plate that can be clipped onto the outer ring (18) of the peripheral wall (12). This method can be used for producing audio prostheses with a rapid and very precise individual adaptation of the otoplasty during a single session.

Description

Method of making a fitting for insertion into a human body cavity

The invention relates to a method for producing a fitting for insertion into a human body cavity using a hollow body, an expandable peripheral wall and a deformable plastic material which is placed under internal pressure in the body cavity and is at least solidified in the body cavity to a just sufficient dimensional stability.

Such a method is known from EP-B-0 289 750. The hollow body here consists of an undeformable rigid stamp and the peripheral wall is formed from a thin, stretchable shell. A hardenable liquid plastic is injected between the stamp and the sheath and pressurized to such an extent that the sheath lies against the ear canal. The plastic hardens in the ear. The fitting is then removed from the ear and the hollow body is removed from the solidified shell, so that, for example, an in-the-ear hearing aid module can be inserted into the cavity created in the fitting. The plastic can contain a photo initiator, so that the solidification process can be initiated by light application. A certain problem with the known method is that the gap between the stamp and the sheath has to be filled with the plastic dimensions from the distal end, but the plastic also has to completely fill the sheath up to the proximal end of the otoplastic in accordance with the anatomy of the ear canal. The viscosity of the plastic mass must be adapted very precisely to the individual anatomy of the ear canal in order to achieve the goal that the necessary widening of the peripheral wall in all areas of the ear canal has taken place when excess plastic mass has escaped from the intermediate space through an outlet opening in the distal end wall. Also determining a suitable one Delivery pressure for the plastic mass will throw up problems in practical application.

US-A-47 1 2 245 and DE-A 24 59 259 represent further proposals for a state of the art in which an intermediate space is created between a non-deformable hollow body and an elastically expandable casing, which forms the later otoplastic In the former proposal, the space is divided into two compartments, the first containing resin and the other hardener. In the latter proposal, a double-walled casing is used, the space between which is widened by inserting an axial slide.

It is also known to use a non-deformable hollow body which is provided with a curable peripheral coating instead of an elastically expandable sleeve. Here, e.g. a resin-impregnated cuff wrapped around a compressible foam core, which is intended to apply the cuff to the ear wall. Proposals of this type are shown in DE-U 87 63 354 and DE-A 38 01 392. In both cases the degree of expansion is limited and the expansion cannot be controlled, e.g. set locally differently according to the anatomical conditions.

The object of the invention is to simplify the method of the type mentioned in practical use and to ensure that the stretchable peripheral wall is optimally adjusted in all local areas of the auditory canal.

This object is achieved with the measures of the type mentioned in that the stretchable peripheral wall is formed by the wall of the hollow body itself, which is closed at its proximal end and at least partially consists of the plastic material mentioned at the outset, that the plastic material before it is produced of the internal pressure is semi-rigid or at least one that Has flowability exceeding degree of stiffness, and that the excess pressure is generated inside the hollow body.

The invention is based on the idea of making the hollow body itself deformable and at least partially curable, in that the hollow body, which is the blank for the adapter, consists of a stretchable and curable material which is then only expanded by an internal overpressure in the ear and in expanded state is at least partially cured. The internal overpressure is the same at all points of the hollow body. Experience shows that even a slight internal overpressure is sufficient to achieve a tight contact of the peripheral wall in the areas of the ear canal, in which the peripheral wall of the blank had larger radial distances before the expansion.

The method according to the invention is not only ideally suited for producing otoplastic fitting pieces, but can also be used for producing fitting pieces of other body cavities, in particular nose fitting pieces. Such nasal adapters serve, for example, to hold tubes that lead into the interior of the body.

In one embodiment, the method according to the invention can be implemented very simply by pumping the hollow body out of a hand-operated dispenser by means of water, glycerin or compressed air after insertion into the ear. The hollow body including its end wall is translucent and consists at least in the area of the peripheral wall of light-curing material, so that only the application of light, in particular in the form of visible light, the solidification of the peripheral wall in the ear is carried out at least to such an extent that the adapter conforms to its shape Removal from the ear no longer changed. The final consolidation can then be carried out outside the ear. An alternative to the method described above is that the hollow body contains a fluid with a pressure-generating agent before insertion into the ear, which fluid can be activated by external application without supply of material in order to build up the internal excess pressure. The fluid is preferably liquid and in particular viscous and contains a swelling agent which is activated by the supply of heat or electromagnetic radiation.

A further development of the method according to the invention can be seen in the fact that the peripheral wall of the hollow body is essentially dimensionally stable before it is inserted into the body cavity and is temporarily converted into a deformable state by the supply of energy. In this case, the peripheral wall of the hollow body preferably consists of a thermoplastic mass which is solid at body temperature and which is temporarily plasticized outside the body cavity by microwave radiation, ultrasound or heat before the hollow body is placed in the body cavity and the internal excess pressure is built up.

According to a development of the method according to the invention, the outer surface of the hollow body is additionally provided with a non-reactive, already cross-linked, elastic coating, which e.g. can consist of silicone or urethane. Such coatings are particularly advantageous for subjects with sensitive skin and can also improve the fit and function of the plastic.

If examples for the solidification of the peripheral wall in the ear by supplying energy have been described in the foregoing, it goes without saying that the solidification can alternatively also be carried out by withdrawing energy, in particular by cooling.

An important development of the invention is that the fit of the

Hollow body after its expansion in the ear can be checked by energy from the distal end of the hollow body in a sealed against the hollow body Channel is passed through this and at the proximal end out of this into the residual volume of the ear canal and the energy change in this residual volume is measured per time. For example, an air overpressure can be built up in the proximal end of the auditory canal if the hollow body is in good contact with the auditory canal on all sides. The reduction of this overpressure per time is then a measure of the quality of the fit. Through the closed channel in the hollow body, however, sound waves can also be introduced into the proximal area of the ear canal and the acoustics at the distal end can be measured. The lower the sound output, the better the fit of the earmold. Also through the channel passing through the hollow body, a microphone can be inserted into the proximal end of the auditory canal, with which an externally generated noise is measured, in order in turn to be able to objectively determine the tightness of the hollow body at the auditory canal without being influenced by subjective sensations. The hearing aid specialist can therefore check the fit in the ear before starting the consolidation process. If the tightness of the system of the peripheral wall in the ear canal is too low after the control measurement, the internal overpressure is increased in accordance with the measurement result and, if necessary, a new control measurement is carried out before the at least partial curing takes place.

The method according to the invention allows a very advantageous further development, insofar as at least one area of the hollow body is given less deformability than other areas of the hollow body before the internal overpressure is generated. In particular, for example, the distal end region of the hollow body can be provided with a lower degree of deformation than the central region of the hollow body. The setting of the degree of deformation can be achieved either by appropriate selection of the wall thickness, but even more simply by partial consolidation of the areas in which high deformability is undesirable. This is usually the case in the distal end region of the hollow body, but can also apply to the proximal end region in order to concentrate the greatest deformation on the central region of the hollow body. With these local partial or full curing, the deformation behavior of the hollow body can be adjusted for the blank, but can also be controlled during individual adjustment.

The invention further relates to a hollow body for producing a fitting piece that can be inserted into a human body cavity, in particular an otoplastic, with a hollow body, an expandable peripheral wall and a medium that can be placed under internal pressure, the peripheral wall being connected to a fixed end wall at the distal end of the hollow body , which has a connection for a pressure generator and this hollow body is characterized according to the invention in that the expandable peripheral wall forms the wall of the hollow body, which is closed at the proximal end, and in that the connection on the end wall opens into the interior of the hollow body. In contrast, in the prior art mentioned at the outset, the peripheral wall forms a shell for the hollow body and the connection opens into the intermediate space between the hollow body and shell.

A further development of the invention is to be seen in the fact that on the hollow body there is a deformable extension which adjoins its distal end and which can be inserted into depressions in order to anchor the earmold in the outer region of the ear and is at least partially solidifiable in the ear. This extension consists of a fixing profile, which e.g. can be inserted into an auricle area and is pressed into the desired position, after which the solidification takes place by at least partial hardening, in particular by light application. Alternatively, this fixing profile can also be adapted and solidified separately, although reworking is then necessary in order to connect this profile to the end wall of the adapter.

The hollow body according to the invention consists of a plastic, which by means of a

Reactive plasticizer is plasticized and possibly contains inorganic fillers and / or pigments for adjusting the color, handling, flow behavior and hardness. As

Polystyrene, polyester, polycarbonate, ABS, PVC etc. are suitable as plastics Reactive plasticizers are chosen compounds that are ethylenically unsaturated, have a plasticizing effect in the corresponding polymer and can be polymerized by the action of energy. These are phthalates with ethylenically unsaturated groups such as, for example, diallyl phthalate or vinyl ether, for example butanediol monovinyl ether or triethylene glycol divinyl ether, but also monomers such as styrene and divinylbenzene. Compounds which have (meth) acrylic groups, such as methyl methacrylate, hexanediol diacrylate and all other mono- and multimeth (acrylates) with alkoxy, hydroxyalkyl, acrylamido and aralkyl groups in their molecular structure, are particularly advantageous. A photo initiator is preferably added to the plastic mass, which initiates the curing of the hollow body by the action of light.

The method according to the invention and the device according to the invention allow the production of an individually optimally adapted otoplastic or nasal plastic in a single session, which lasts less than an hour. This adjustment does not require trained specialist personnel. In particular with an advantageous embodiment, which consists in that the end wall consists of an outer ring part integrally connected to the peripheral wall and an end plate detachably inserted therein, the manual activity is to a minimum, because after removal of the end plate, which preferably latches on the outer ring , only a suitable hearing aid module needs to be clipped into the possibly multi-part outer ring in order to create an in-the-ear hearing aid.

The invention is described in more detail with reference to the drawing, which represents an exemplary embodiment.

It shows:

FIG. 1 shows a schematic illustration of a hollow body positioned in the ear canal before the formation of an ear adapter, FIG. 2 the representation according to FIG. 1, but after expansion of the hollow body with adaptation to the anatomy of the ear canal, and

FIG. 3 shows a cross section through the hollow body on a larger scale.

A hollow body 10 of roughly frustoconical shape with a flat distal end and a rounded dome-shaped proximal end has a peripheral wall 1 2 made of expandable, light-curing plastic and a flat end wall 14 that closes the peripheral wall 1 2 at the distal end and is essentially rigid . As can be seen from FIG. 3 results, the peripheral wall 1 2 is bag-shaped or bag-shaped and ends at the distal end in the area of an outer ring 1 6 with an oval contoured opening 18. In this opening, an end plate 20 is inserted and, in the exemplary embodiment, screwed detachably with circumferentially distributed screws. Alternatively, the end plate 20 can also be latched to the outer ring 16 by means of suitable latching connections. The hollow body formed in this way is hermetically sealed and a tube 22, which serves as a handle and opens at the same time into the hollow body, is connected via a hose to a device for generating pressure. The entire peripheral wall 1 2 including its proximal tip is provided with a thin elastic coating 24. A channel 26 passes through the end plate 20, further the interior of the hollow body 10 and finally protrudes from the hollow body at its proximal end with sealing by the tip of the peripheral wall 12. When liquid is pumped up, the air escapes through a vent hole 32, which is then closed.

The peripheral wall 1 2 consists of an expandable, light-curing material. The

End plate 20 is translucent. In the area of the outer ring 16 is the

Circumferential wall 1 2 at least partially cured, so that there is a firm fit for the end plate 20. The hollow body thus prefabricated is inserted into the auditory canal 28 of a subject, for example by a specialist in a hearing aid laboratory, as shown in FIG. 1 illustrates. By actuating a device for generating pressure, an internal overpressure is then generated in the hollow body 10 which, depending on the degree of softness of the peripheral wall 1 2, is sufficient to expand the peripheral wall 1 2. This circumferential wall 1 2 fits closely to the auditory canal 28, as shown in FIG. 2 illustrates schematically. The hollow body 10 can then be released and the fit of the hollow body 10 is checked. In the simplest case, this takes place in that an overpressure is generated by the hose 26 in the end region 30 of the auditory canal 28 and the pressure reduction per unit of time is measured. If the pressure drops below a preselected period of time, the internal overpressure in the hollow body 10 is increased through the tube 22, otherwise the adaptation of the adapter is finished. Alternatively, the tightness can also be checked by sound measurements.

After the hollow body 10 has reached its fit state, it is at least partially cured while maintaining the excess pressure, so that the fit is retained after relieving pressure from the interior of the hollow body. The at least partial solidification is preferably brought about by light application through the end plate 20. Then the hollow body 10 is removed from the ear, the end plate 20 with the channel 26 is removed. The oval opening 1 8 is then exposed, so that e.g. a hearing aid module for an in-the-ear hearing aid can be inserted into the interior of the hollow body 10. The outer ring 1 8 is used for locking, so that manual rework usually. omitted.

Claims

PATENT CLAIMS

1 . A method of manufacturing a fitting for insertion into a human body cavity using a hollow body (10), a stretchable peripheral wall (1 2) and a deformable plastic mass which is placed under internal pressure in the body cavity and at least to a just sufficient dimensional stability in the body cavity is solidified, characterized in that the expandable peripheral wall (1 2) is formed by the wall of the hollow body (10) itself, which is closed at its proximal end and consists at least in part of the plastic mass, that the plastic mass before generating the inner Overpressure is semi-rigid or at least has a degree of rigidity that exceeds the flowability, and that the overpressure is generated in the interior of the hollow body (10).

2. The method according to claim 1, characterized in that the hollow body (10) contains a fluid with a pressure generating means which can be activated by external application in order to build up the internal excess pressure.

3. The method according to claim 1 or 2, characterized in that the peripheral wall (1 2) of the hollow body (10) is temporarily converted into a deformable state by supplying energy before it is inserted into the body cavity.

4. The method according to any one of claims 1 to 3, characterized in that the solidification of the plastic mass takes place by supplying energy.

5. The method according to any one of claims 1 to 3, characterized in that the solidification of the plastic mass is carried out by energy withdrawal.

6. The method according to any one of claims 1 to 5, characterized in that after generating the internal excess pressure in the hollow body (10) an energy medium from the distal outside of the hollow body (1 0) through a, the hollow body (1 0) penetrating channel (26) in the proximal end region (30) of the auditory canal (28) and the change in the energy quantity per unit of time is determined in this region to check the accuracy of fit of the expanded hollow body (10).

7. The method according to any one of claims 1 to 6, characterized in that at least one end region of the hollow body (10) is equipped with a lower deformability than the central region of the hollow body (10) before the generation of the internal overpressure.

8. The method according to any one of claims 1 to 7, characterized in that the solidification of the peripheral wall (1 2) by means of high-frequency electromagnetic radiation with a wavelength in the range of 200 - 5000 nanometers.

9. The method according to any one of claims 1 to 8, characterized in that the outer surface of the peripheral wall (1 2) before the insertion of the hollow body (10) in the body cavity is provided with a non-reactive, already cross-linked elastic coating (24).

10. Hollow body for producing a fitting piece that can be inserted into a human body cavity, in particular an otoplastic, with an expandable peripheral wall (1 2) and a medium that can be placed under internal pressure, the peripheral wall (1 2) at the distal end of the hollow body (10) a fixed end wall (1 8, 20) is connected, characterized in that the stretchable Circumferential wall (1 2) forms the wall of the hollow body (10), which is closed at the proximal end.

1 1. Apparatus according to claim 10, characterized in that the end wall (1 8, 20) has a connection (22) which opens into the interior of the hollow body (10) for a pressure generator.

1 2. Device according to claim 1 0, characterized in that the hollow body (10) contains a fluid with a predetermined amount of a swellable agent which can be activated by external energy supply, and the amount is such that after activation the internal overpressure in the hollow body (10) sets.

1 3. Device according to one of claims 10 to 1 3, characterized in that the peripheral wall (1 2) at least at the distal end of the hollow body (10) has a lower deformability than in its central region.

14. The apparatus according to claim 1 3, characterized in that the area with less deformability of the peripheral wall (1 2) is partially cured.

1 5. Device according to one of claims 10 to 14, characterized in that the hollow body (10) has a, at its distal end adjoining, deformable extension which can be applied to anchor the otoplastic in the outer region of the ear and at least partially in the ear is solidifiable.

1 6. Device according to claim 1 5, characterized in that the extension is integrally connected to the hollow body (10).

1 7. Device according to one of claims 10 to 1 6, characterized in that the end wall (18, 20) from one, with the peripheral wall (1 2) in one piece connected outer ring (18) and a releasably inserted in this end plate (20).

8. The device according to claim 1 7, characterized in that the end plate (20) on the outer ring (1 8) is locked.

9. Device according to one of claims 10 to 1 8, characterized in that the hollow body (10) has a channel (26) which extends from its distal end to the proximal end and is sealed off from the interior of the hollow body (10).