JP2001516619A - Equipment for ventilating the middle ear - Google Patents

Abstract

  (57) [Summary] The present invention relates to a device for ventilating the middle ear by means of a ventilation tube made of a tissue compatible material, preferably titanium, and having a through channel for air communication between the tympanic cavity and the outside air. The ventilator tube, on the one hand, is arranged to be introduced into the bone tissue and, on the other hand, a passage through the skin, on the other hand, which is designed to obtain a permanent fixation in the bone tissue. A rear portion (6) forming The ventilation tube is further made of an outer tube (1) made of said tissue-compatible material and the through-channel (14) which is removably arranged in the outer tube and whose inner hole is for air communication between the tympanic cavity and the outside air. And an inner tube (8) forming

Description

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a device for ventilating the middle ear by means of a ventilation tube made of a tissue-compatible material, preferably titanium, having a through channel for air communication between the tympanic cavity and the external air.

As is well known, the function of the middle ear is to transmit sound energy from the environment to the inner ear, where the sound signal undergoes a complex process for interpretation. Transmission of sound energy from this environment to the inner ear requires impedance transformation of the sound signal. This is because sound energy is transferred from one medium (air) to another medium (liquid) located in the inner ear and having significantly higher impedance than air. With the help of the shape of the ossicles and surrounding organs, the impedance transformation takes place in the middle ear. If normal hearing is to be maintained, the basic condition is that normal impedance in the middle ear is retained and movement in the transmission chain is not attenuated, which requires a properly ventilated middle ear I do.

[0003] However, the most common symptom in otology is the accumulation of fluid in the middle ear, which results in weakened hearing. This is especially common among children but also occurs in adults with chronic inflammation of the middle ear. Therefore, puncturing the eardrum and providing a ventilation tube is a common operation. In the United States alone, almost one million operations of this type are performed each year. In Western Europe, the United States, and Japan, a total of about 5 million ventilation tubes are used each year for these operations, most of which are performed on children under anesthesia.

[0004] Some of these children with middle ear problems do not improve as they grow up, but instead remain problematic and become chronic at adulthood. The result is a gradual destruction of the function of the middle ear. In most cases, there is a progressive destruction of the middle ear with impaired hearing, which gradually leads to severe hearing impairment. These patients are usually initially assisted by a tube through the tympanic membrane in a traditional manner, but the tube is removed after a short time and the tympanic membrane is increasingly damaged by these repeated procedures, and for this reason, the method requires the patient Does not help in the long run. Therefore, it is desirable to develop a method that can ensure ventilation of the eardrum even in these patients.

[0005] The standard procedure to date is middle ear repair, which involves the removal of excess connective tissue and enlargement of the middle ear primarily by resection of bone in the mastoid area. This surgery increases the patient's chances of acquiring better hearing, but must be combined with an air channel for successful results. This surgical intervention is relatively large and cannot be easily repeated to diagnose a middle ear condition. It is therefore desirable to have a channel that is large enough to accommodate a fiber optic device for examining the condition of the middle ear.

Where conventional methods of ventilation through the tympanic membrane cannot be used, other methods have been attempted, especially ventilation lines through the Oystahiy or ventilating tubing between the edges of the eardrum, ie, bone and soft tissue. Was. However, none of these methods have been successful and are not commonly used.

It is also known to design ventilation ducts in the eardrum with an outer surface made of titanium with the aim of reducing the risk of exclusion and avoiding repeated surgical intervention. As is known, metallic titanium has been found to have unique properties of biocompatibility with body tissue. Various areas of clinical application have been successfully attempted. Various types of fasteners fixed in bone have been used to fix various types of prostheses, such as dentures in the jawbone of the oral cavity and hearing aids fixed in the skull. In both cases, the titanium surface conforms very well to both bone tissue and the mucous membrane or skin of the oral cavity.

[0008] Titanium with good biocompatibility has been shown to have a relatively high affinity to bind blood products and form tissue even on surfaces that are not initially in contact with tissue. In particular, this led to occlusion more easily if they were made of titanium, rather than those made of polymeric materials, if they were made of titanium. In addition, tubes fixed within the eardrum cannot be practically cleaned because the eardrum is sensitive to contact.

[0009] Swedish patent application 87703694-3 describes a ventilation tube for temporary fusion into an eardrum consisting of a plastic tube with a continuous coating of titanium oxide on the outside. Alternatively, the ventilation tubing may consist of a titanium tubing whose interior air channel has been treated with a layer that negates the normal affinity of titanium for bodily secretions and body tissue in order to prevent blockage of the ventilation channel. it can.

[0010] While the aforementioned ventilation pipes have advantages over conventional ventilation pipes made of titanium, this type of ventilation pipe does not offer a solution if permanent fixation is sought. Again, a certain amount of blockage of the ventilation channel occurs sooner or later, which requires cleaning.

There is currently no satisfactory way to achieve the desired ventilation of the middle ear, especially in adults with chronic inflammation of the middle ear.

It is an object of the present invention to remedy the above difficulties and to create a permanent ventilation channel for the middle ear.

According to the invention, this object can be achieved by the fact that the ventilation tube is designed so that it can be fixed in bone tissue, for example in the mastoid bone. The ventilation tube thus comprises, on the one hand, an anterior part which is arranged to be introduced into the bone tissue and is designed for obtaining a permanent fixation of the ventilation tube, and, on the other hand, a posterior part which forms a passage through the skin. . In addition, the ventilation channel is preferably designed in such a way that occlusion is minimized, both through the design of the outer tube and the choice of material for the inner channel of the ventilation tube. The ventilation channels are also designed in such a way that the course of the disease in the middle ear can be monitored using fiber optics, and in this way the outcome of the treatment can be improved.

According to one advantageous embodiment, the ventilation tube comprises an outer tube made of a histocompatible material capable of growing firmly in bone tissue and functioning in the outer and inner epithelial passages. The ventilation tube further includes an inner tube introduced into the outer tube and having the necessary characteristics to minimize occlusion. The inner tube is additionally removable to allow cleaning or replacement without damaging the supporting tissue. When the inner tube is removed, a sufficiently large channel is obtained through the ventilation tube to allow the middle ear to be examined with fiber optics.

According to a further embodiment, the inner tube is provided with a membrane to allow the ventilation of gases (eg air, water vapor), but in contrast to prevent the entry of liquids and particles / germs. Also in this case, the inner tube (insert) is easy to replace.

[0016] According to a third embodiment, the outer tube is free in the perforated bone, eg, the mastoid bone, making it more difficult for tissue to grow across the inner end of the tube. It is designed to be surface-modified to Such surface coatings are known surface coating methods,
Obtained, for example, by sputtering and by known materials, such as polyurethane or silicon.

In all embodiments, the outside of the outer tube is designed in such a way that mechanical stability to the bone tissue is obtained during the fusion phase, which is a prerequisite for osteointegration.

The present invention will be described in more detail below with reference to the accompanying drawings, which show an example of a convenient embodiment according to the present invention.

The ventilation tube comprises an outer tube 1 made of titanium and having a surface made of titanium oxide which is automatically formed during manufacture. The outer tube includes an anterior part 2 with external threads 3 arranged to be introduced into a hole made in the bone of the middle ear, so that the ventilation tube is a good machine for surrounding bone tissue during the healing phase. Obtain strategic stability. This is a prerequisite for osseointegration and permanent fixation of the ventilation tube. The threaded portion has a cutting edge 4 at its forefront to allow some self-tapping / cutting of bone material from surrounding bone tissue when the tube is introduced into the pre-drilled hole in the bone. It is designed to have a cavity 4a for accommodating the held and removed bone shavings.

The insertion end 5 of the front part is screwless and faces the bore 14 to prevent material from being scraped and released from the inner tube when the inner tube 8 is disengaged and remaining in the middle ear. With slightly rounded edges. After application, the threadless portion extends a short distance into the middle ear, so that its free end is surface-coated, for example with a polymeric material, for example polyurethane or silicon, to prevent tissue overgrowth.

The ventilation tube further includes a posterior portion 6 whose outer surface is appropriately shaped for passage through the skin, which portion secures the ventilation tube in the bone tissue before it passes through the skin from the bone / skin interface. It is of a length such that it is arranged to extend into open air.

There is a continuous hole or channel 7 extending through the ventilation tube, to which an inner tube 8 made of a polymeric material, for example polyurethane or Teflon, is applied.

The opposite end 9 of the outer tube 1 is designed to have a mounting screw 10 for mounting an assembly tool for screwing the ventilation tube into the bone. This mounting screw can additionally be used for other purposes, such as mounting various inserts, for example filters, membranes or capillaries 11 of a type known per se. It can be used if needed additionally for the installation of an air pump for forced ventilation of the middle ear (indicated by nipple 12 in the figure). Another area of application for the mounting screw 10 is to form a mounting for a plug, ie a solid insert 11. The hole 7 through the outer tube has a diameter such that a fiber optic device can be introduced for examining the middle ear.

The inner tube 8 has a length adapted to the length of the outer tube such that some free ends are exposed in the middle ear when the inner tube is fully pushed into the outer tube. The inner tube is furthermore provided with a flange 13 of maximum diameter exceeding the diameter of the hole 7, so that the inner tube is prevented from going too far into the middle ear. The inner tube can be easily replaced and removed for cleaning. Further, the diameter and length are chosen so that the liquid cannot easily pass through the inner channel 14 when showering or washing. Instead of the separate filters, membranes or capillaries 11 described above, they can for example be incorporated in an inner tube with the membrane. Such a membrane prevents water and bacteria from entering and seals from the outer tube.

The present invention is not limited to the embodiments shown by way of example, but can be modified within the scope of the appended claims.

[Brief description of the drawings]

FIG. 1 shows an example of a convenient embodiment according to the present invention.

[Procedural Amendment] Submission of translation of Article 34 Amendment of the Patent Cooperation Treaty

[Submission date] March 6, 2000 (200.3.6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

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Claims (11)

[Claims] 1. A device for ventilating the middle ear with a ventilation tube made of a tissue compatible material, preferably titanium, having a through channel for air communication between the tympanic cavity and the outside air, wherein the ventilation tube comprises: On the one hand, an anterior part (2) which is arranged to be introduced into the bone tissue and is designed to obtain a permanent fixation in the bone tissue and, on the other hand, a posterior part which forms a passage through the skin (6) An apparatus comprising: 2. The penetration channel (14) for air communication is characterized in that it is designed to be more difficult to grow into tissue, which means reducing the risk of the channel being occluded. The apparatus according to claim 1, wherein: 3. An outer tube (1) in which a ventilation tube is made of said histocompatible material, preferably titanium, and is removably arranged in the outer tube, the inner hole of which is in air communication between the tympanic chamber and the outside air. Device according to claim 2, characterized in that it comprises an inner tube (8) forming the through-channel (14) for the same. 4. The device according to claim 3, wherein the inner tube is made of a polymer material such as polyurethane or Teflon. 5. The anterior part (2) of the outer tube is provided, in whole or in part, with external threads (3) for good mechanical stability against the surrounding bone tissue during the fusion phase, and 4. The device according to claim 3, wherein the outer tube has a threadless insertion end (5) arranged to extend into the middle ear a short distance after being applied in the bone tissue. 6. The device according to claim 5, wherein the insertion end of the anterior part is surface-coated with a material covering it to prevent tissue from growing, for example a polymeric material. 7. The posterior part (6) of the outer tube forming the passage through the skin is arranged so that after fixation of the ventilation tube into the bone tissue it extends from the bone / skin interface through the skin and into open air. 4. The device according to claim 3, wherein the device is of a length such that 8. The inner tube (8) has a length greater than the length of the outer tube (1) and has a flange (13) to prevent the inner tube from being inadvertently pushed too far into the middle ear. The device according to claim 3, characterized in that: 9. The outer tube end (9) opposite the insertion end is provided with a mounting (10) for various inserts (11, 12) such as filters, membranes or capillaries, air pumps or plugs. 6. The device according to claim 5, wherein 10. Inserts (11, 12) such as filters, membranes or capillaries.
) Is instead incorporated into the inner tube (8). 11. The insertion end (5) is rounded to prevent the inner tube (8) from being scraped against the edge of the opening and causing a risk of separated tissue material remaining in the middle ear when the inner tube is removed. 6. The device according to claim 5, characterized in that it has a shape and a gentle transition towards the bore (opening of the ventilation channel).