JPH0571268B2 - - Google Patents

Description

Detailed Description of the Invention "Technical Field" The present invention provides a device that is inserted into the middle ear cavity through the eardrum to promote drainage of internal exudate and ventilation of the middle ear when treating otitis media with effusion. This invention relates to a ventilation tube for middle ear tube placement.

"Prior art and its problems" The Eustachian tube has the function of balancing the pressure between the middle ear and the outer ear, and the function of appropriately excreting and cleaning secretions in the middle ear cavity.
If this Eustachian tube function is impaired for some reason, the negative pressure within the middle ear cavity increases, increasing congestion of the mucous membrane within the middle ear cavity and excessively increasing exudate, resulting in otitis media with effusion. Such otitis media with effusion tends to last for a long time, and if left untreated or without proper treatment, it tends to develop into sequelae and hearing loss due to tissue changes within the middle ear cavity.

One of the effective treatments for Eustachian tube dysfunction is transtympanic tube insertion therapy. In this method, the eardrum is incised, exudate is sufficiently drained, and then a small ventilation tube is inserted through the incision and left in the eardrum for a certain period of time. This ventilation tube is expected to excrete internal exudates and ventilate the middle ear, leading to healing of mucosal lesions within the middle ear.

Conventionally, such ventilation tubes have been made of Teflon, silicone, polyethylene, or the like. However, when symptoms persist for a long time, conventional ventilation tubes often cause a foreign body reaction as the material has poor affinity for the living body, and the tubes often separate from the eardrum due to rejection by the living body. Ta.

OBJECT OF THE INVENTION In view of the problems of the prior art described above, an object of the present invention is to provide a ventilation tube for middle ear tube placement that can be left in the tympanic cavity for a long period of time.

``Structure of the Invention'' The present invention uses hydroxyapatite [Ca ₁₀ (PO ₄ ) ₆ (ON) ₂ ], which has the same composition as human bone, as the material of the ventilation tube in order to increase its compatibility with living organisms. This was done with a focus on composition.

That is, the ventilation tube for intramiddle ear tube indwelling of the present invention is characterized in that at least the outer peripheral surface is made of hydroxyapatite.

Therefore, when this ventilation tube is inserted into the tympanic membrane, the ventilation tube does not undergo a rejection reaction due to the biocompatibility of hydroxyapatite, and can be left in the tympanic cavity for a long period of time.
A sufficient therapeutic effect can be expected.

The ventilation tube of the present invention may be formed entirely of hydroxyapatite, or may have a skeleton formed of a suitable synthetic resin, metal, etc., and the outer peripheral surface thereof may be coated with hydroxyapatite. can also be adopted.

Embodiment of the Invention FIGS. 1 and 2 show an embodiment of a ventilation tube for middle ear tube placement according to the present invention.

The ventilation tube 11 has a cylindrical shape as a whole, and a ventilation hole 12 is formed through the center. The middle part of the cylindrical body forms a reduced diameter part 13 with a slightly reduced diameter, and an insertion inner end part 14 inserted into the inner side of the eardrum and an insertion outer end part 15 located on the outside thereof have an enlarged diameter. There is. Furthermore, the insertion end 14 has a tapered shape whose diameter gradually increases from the diameter reduction part 13, making it easy to insert into the eardrum hole, while the insertion outer end 15 has a diameter reduction. A stepped portion 18 is formed between the ventilating tube 11 and the portion 13 so that the ventilation tube 11 does not easily fall into the middle ear cavity. Further, the inner diameter of the vent hole 12 near the opening on the outer insertion end 15 side is enlarged to facilitate insertion of a tube or the like for sucking out exudate into the opening. In this example,
The length of each part is 2.7 mm, the overall length a in the axial direction,
The minimum inner diameter b of the ventilation hole 12 is 1.0 mm, and the insertion outer end 1
The outer diameter c of 5 is 2.5 mm, and the outer diameter d of the reduced diameter part 13 is 1.4
mm, and the outer diameter e of the insertion inner end 14 is 1.8 mm. And this ventilation tube 11
is made entirely of hydroxyapatite. This ventilation tube 11 is made by press-molding hydroxyapatite powder, for example.
It can be manufactured by cutting a block obtained by sintering.

Next, how this ventilation tube 11 is used will be explained. In FIGS. 3 and 4, 21 is the external auditory canal, 22 is the tympanic membrane, 23 is the middle ear cavity, 24 is the malleus, 25 is the incus, and 28 is the stapes. Therefore, when performing transtympanic tube insertion therapy for otitis media with effusion, etc., first make a small incision in the eardrum 22 with a scalpel, etc., grasp the ventilation tube 11 with small forceps, and insert it into the external auditory canal 21. , the insertion inner end 14 of the ventilation tube 11 is inserted into the incision in the eardrum 22 . Then, the indwelling position is adjusted with a pick, and the reduced diameter portion 13 of the ventilation tube 11 is fitted into the incision of the eardrum 22 and held. At this time,
The insertion outer end 15 engages the outside of the incision in the eardrum 22, and the ventilation tube 11 is inserted into the eardrum 22.
Prevent yourself from becoming depressed. In this way, by inserting and holding the ventilation tube 11 into the eardrum 22, exudate in the middle ear cavity 23 is excreted through the ventilation hole 12 of the ventilation tube 11, and also through the ventilation hole 12 into the middle ear cavity 23. Ventilation is provided to promote healing. In addition, if necessary, the suction tube ventilation hole 12
It may also be inserted into the opening of the tube to suck out exudate. Since the ventilation tube 11 of the present invention is made of hydroxyapatite, its biocompatibility allows it to maintain the eardrum 22 for a long period of time.
, and a sufficient therapeutic effect can be expected. When the symptoms are improved and the treatment is almost completed, the ventilation tube 11 is grasped with forceps or the like and taken out.

Note that the ventilation tube 11 is located on the extraction side, as shown by the imaginary line in FIG. A wire 16 for removal is attached to the outer insertion end 15.
Alternatively, a pin 17 may be provided.

"Effects of the Invention" As explained above, according to the present invention, at least the outer peripheral surface is formed of hydroxyapatite, so it has good biocompatibility and can be retained in the eardrum for a long period of time, and the treatment can be performed satisfactorily. It becomes possible to do so.

[Brief explanation of drawings]

Fig. 1 is an upper half sectional view showing an embodiment of the ventilation tube for intramiddle ear tube placement according to the present invention, Fig. 2 is a perspective view of the ventilation tube, and Fig. 3 is a perspective view of the ventilation tube. FIG. 4 is an explanatory cross-sectional view showing how the ventilation tube is used, as seen from the outer ear side. In the figure, 11 is a ventilation tube, 12
22 is the air vent, 22 is the eardrum, and 23 is the middle ear cavity.

Claims (1)

[Claims] 1. In the ventilation tube for middle ear tube placement, which is inserted into the middle ear cavity through the tympanic membrane to drain exudate from the tympanic membrane, ventilate the middle ear, etc., at least its outer peripheral surface is made of hydroxyapatite. Ventilation tube for middle ear tube placement.