The eustachian tube is embryologically formed by an invagination of the nasopharyngeal mucosa, and is an extension and modification of the respiratory mucosa, which is composed of ciliated cells and mucus blanket. Therefore, the eustachian tube has a functional mucociliary system, which plays a key important role in the defense mechanism of the tubotympanum. Our study has concerned the pathophysiology of the mucociliary system induced by a variety of pathological factors including endotoxin, allergic inflammatory mediators, and allergic responses. This study has also experimentally discussed the possible preservative medication for otitis media with effusion.
Ciliary activity of the eustachian tube decreased in a doser esponse fashion in the presence of bacterial endotoxin. Intratympanic inoculation of bacterial endotoxin induced ciliary depression and prolonged mucociliary clearance of the eustachian tube, resulting in middle ear effusions. Intratympanic inoculation of a larger concentration of endotoxin resulted in a longer persistence of middle ear effusions.
We examined the effect of histamine and its H1 and H2 blockers on the eustachian ciliary activity. Ciliostimulatory effects were demonstrated for histamine. Such ciliostimulatory effects were not affected by Hl-blocker but were reduced by H2-blocker. Therefore, histamine could enhance ciliary activity through combining with H2-receptor. Intratympanic injection of histamine induced accumulation of middle ear effusions and mucociliary dysfunction. The duration of the pathology depended on the concentration of histamine for intratympanic injection.
Platelet activating factor (PAF) had no effect on the in vitro ciliary activity, but reduced ciliary activity in the presence of bronchoalveolar lavage fluid in a dose response fashion. Intratympanic injection of PAF induced mucociliary dysfunction and eosinophil accumulation in the eustachian tube, resulting in middle ear effusions.
Roxythromycin (RXM) and a Chinese medicine, Sai-rei-to are reported to have a ciliostimulatory effect. We examined whether pretreatment with these drugs could prevent the middle ear from endotoxin-induced otitis media with effusion. Guinea pigs were treated with two doses of these drugs for two weeks. Then bacterial endotoxin was inoculated into their tympanic cavities. Sai-reto alleviated the endotoxin-induced mucociliary dysfunction and accumulation of middle ear effusions in a dose response fashion. RXM also alleviated such endotoxin-induced pathologies, but such effects were not dependent upon the concentrations of RXM administered.
An inference has been derived from the study that the mucociliary system of the eustachian tube plays a key important role and easily damaged by a variety of irritant factors and that ciliostimulatory medication could be useful in the treatment of recurrent otitis media with effusion.

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The effect of oral immunization on nasopharyngeal colonization by nontypeable Haemophilus influenzae (NTHi) and the influence of nasal allergy on otitis media with effusion (OME) were investigated.
Mice were immunized orally with outer membrane proteins of NTHi and nasopharyngeal clearance of NTHi was examined. IgA antibody activities against NTHi in nasopharygeal secretions were remarkably increased and the number of NTHi cultured from nasopharyngeal lavage was significantly reduced by oral immunization. Sonotubometry showed that the presence of nasal allergy causes tubal dysfunction. Anti-allergic drug was effective to clear middle ear effusion in experimental animal model and in patients with OME and nasal allergy. The results suggest that mucosal immunity in the nasopharynx and nasal allergy are associated with the tubal dysfunction and the pathogenesis of OME.

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Although dysfunction of the eustachian tube (ET) has been widely accepted as one of the main causes of otitis media with effusion (OME), its details such as site or mechanism have not been fully clarified yet.
In this article, previous studies regarding those issues were reviewed and found that: 1. Ventilatory dysfunction appeared to lie near the pharyngeal orifice in many of ETs with OME.
2. Constriction of the ET instead of dilation on swallowing was seen in 30-80% of patients with OME.
3. Inflammatory conditions in the nasopharynx such as hypertrophied adenoids or blockage of the tubal orifice by nasal discharge were closely related with the tubal constriction on swallowing.
From these results, treatment of inflammatory conditions of the nasopharynx was considered to be important in the management of OME in a sense that it may improve the tubal function as well as the elimination of infection in the middle ear with OME.

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The clinicopathological features of 87 cases (35 males, 52 females, aged from 13 to 88) of patulous eustachian tube (ET) were demonstrated and discussed.
In addition to the typical symptoms of fullness of the ear, autophony, and tinnitus, other symptoms were earache (19%) and dizziness (6%). Three-fourths of the males over 50 years old had a weight loss over 5kg. Besides degeneration of the ET being the predisposing factor, a weight loss was a causative factor of patulous ET in these cases. Among 8 pregnant cases of patulous ET, 7 cases had a history of weight loss and/or a low body mass index (BMI) except for a case of myoclonus. While weight loss was a causative factor, low BMI was a predisposing factor of patulous ET.
Regarding to the findings of the pharyngeal orifice, three-fourths of the cases had a typical patulous type and one-fourth an atypical type. The isthmus portion of the ET holds the patulous ET. The patulous ET was associated with OME, mastoiditis, myoclonus, irradiation, and low frequency seusorineural hearing loss.

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We reported 9 cases of patients with congenital anomaly of the ossicles without malformation of the external auditory canal. Disconnection of the incudostapedial joint was found in 4 cases, malleus fixation in 2 cases, stapes fixation in one case. Bony closure of the round window in two cases with and without disconnection of incudostapedial joint was recognized. Audiograms showed conductive hearing impairment in 8 cases and mixed hearing impairment in one case. Air-bone gaps ranged from 27 to 66 dB in those cases. On X-ray films, ossicular anomalies were not detectable in all cases. Tympanogram showed Ad type in 2 cases, As type in 3 cases, and A type in 4 cases. Sclerotic type of the ossicular chain was found in 4 cases, and in 3 of these 4 cases, their tympanograms were As type. Five cases revealed disconnection type of the ossicular chain, and 2 of 5 cases showed Ad type. The tympanic cavity was exposed and examined without ossicular chain reconstruction in 2 of 9 cases, because of bony closure of the round window with abnormal location of the facial nerve. The ossicular chain was reconstructed in 7 cases. Autografts of a bone tip was used in 1 case, and the malleus was in 2 cases. Hydroxyapatite ceramic ossicular replacement prosthesis (CORP) was used in 3 cases. Bony fusion of the malleus with the tympanic anulus was drilled down in one case. After surgery, postoperative hearing improvement was achieved in 6 (67%) of 9 cases. These findings suggest that surgical reconstruction of the ossicular chain should be considered in the congenital anomaly with air-bone gap.

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There have been patients with secretory otitis media (SOM) who had frequent ear infections or dark red discharge while receiving middle ear tube treatment and had poor prognosis. In some of these patients cholesterol crystals were detected microscopically in the middle ear fluid or ear discharge.
Microscopic detection of cholesterol crystals in the middle ear fluid is thought helpful for determining prognosis.
There have been no reports on frequency of cholesterol crystals found in middle ear fluid in SOM patients or when cholesterol crystals appeared, therefore the middle ear fluid was examined.
The findings are summarized as follows: 1. In the fluid of 124 of 172 ears of 86 children with SOM, cholesterol crystals were detected (cholesterol positive) in 98 ears (79%). The children ranged in age from 2.7 to 13.8 years. Of 86 children 43 were boys (50%). One of the reasons for the high percentage was that all of our patients were first seen at another clinic and referred to us due to poor clinical course of the disease.
2. Cholesterol crystals were found in 81.7% of glue middle ear fluid and in 81.8% of chocolatecolored middle ear fluid. The development of pneumatization of the temporal bone was small in all ears.
3. Of the ears treated with middle ear tubes, those in the cholesterol positive group had more frequent infections and dark red discharge than those in the cholesterol negative group or in the unexamined ones. 35 ears (36.8%) of the cholesterol positive group were accompanied with infections, although 3 ears (25.0%) in the negative group and 8 ears (24.2%) in the unexamined group also were accompanied with infections.
Dark red discharge was found in 31 (32.6%), 5 (20.8%) and 3 (9.0%) respectively.
4. In the patients treated with middle ear tubes for more than 2 years, 17 of 32 (53%), 2 of 3 (67%) and 5 of 8 (63%) respectively were completely cured.
5. Our studies demonstrated that the presence of cholesterol crystal in middle ear fluid is important when we considered the natural history of SOM, especially in severe cases. We strongly recommend microscopic examination of middle ear fluid for SOM.

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The reconstruction of the posterior meatal wall using fascia was performed at the first stage operation for cholesteatoma and severe otitis media purulenta patients. Twenty seven ears were operated on by this method. The size of the external ear canal after operation became wide in the patients with poor middle ear aeration or operated on by canal down method. The first and second operation of planned stage tympanoplasty by this surgical technique are simple, and the problems caused by open cavity after operation is limitad. This technique is also able to apply to the second staged operation in the selected patients.

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Seventy-four ears received type III or modified type III and thirty seven ears received type IV or modified type IV tympanoplasty between December 1983 and March 1993 were followed for more than one year.
Postoperative complications were as follows; 1) exposure or extrusion of the columella occurred in 6 (24.0%) of 25 ears using plastipore PORP and in 7 (38.9%) of 18 ears using plastipore TORP, 2) attic retraction pockets were found in 36 (57.1%) of 63 ears with cholesteatoma and in 14 (29.2%) of 48 ears with non-cholesteatoma, and 3) residual cholesteatoma was found in 1 (1.6%) of 63 ears with cholesteatoma, and retraction cholesteatomas were found in 5 (7.9%) of 63 ears with cholesteatoma and in 2 (4.1%) of 48 ears with non-cholesteatoma.
Compared with postoperative hearing results after one year, the hearing after more than three years was deteriorated in type III tympanoplasty. It was suggested that the cause was impairment in mobility of the ossicles or columella by advance of the attic retraction or re-adhesion of the ear drum.
Since attic retraction pocket or retraction cholesteatoma occurred even in postoperative ears with non-cholesteatoma, it was expected that mastoid obliteration is a better procedure in order to prevent postoperative attic retraction not only for cholesteatoma but also for non-cholesteatoma which has severe lesion around the tympanic isthmus.

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We experienced 3 cases (7 to 9 years old) who presented with sudden deafness after the onset of parotid swelling during a period from February to May in 1994. All patients have not received immunization, and unilateral sensorineural deafness was not improved in spite of the treatment.
In Hachinohe area mumps has been epidemic from November, 1993 and about 10% of children in Hachinohe city suffered mumps. So the incidence of mumps deafness was presumed to be at least 0.005%.
Most of the patients with mumps were under 4 years of age. So, the complaint of deafness was obscure to make diagnosis in some cases, which posed a problem.
In order to prevent mumps deafness, the positive measures including vaccination should be taken.

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For the purpose of studying the utility of evoked oto-acoustic emissions (EOAEs) in newborns hearing screening, EOAEs, behavioral observation audiometry (BOA) and auditory brain-stem responses (ABR) were recorded in the ears of 30 infants in the neonatal intensive care unit (ward).
The age of the infants examined in the ward was 6-126 days old and the.postconceptional age was 25-41 weeks old.
In the ward 83.3% of BOA and 80% of EOAE and 93.3% of ABR were successful.
In healthy newborns, the success rate of EOAE recordings were more than 90% in the litterature.
Compared with healthy newborns, the infants in the NICU are much more difficult to test because of noise or stress during recording.
However EOAEs could hold some promise as an objective, easy and noninvasive test for screening auditory dysfunction in infants.
In conclusion, we recommend EOAE combined with BOA for newborns hearing screening, before ABR was attempted with administration of sedatives.

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A 63-year-old man presented with bilateral hearing impairment of 25 years' durution. At 12 years, he complained of severe hearing loss and tinnitus, but no vertigo. Blue sclera was noted and the patient was also suffered from bone fracture four times, and he was diagnosed as having Van der Hoeve syndrome. A stapedotomy was performed in his left ear and subsequently his left hearing recovered. However, 5 years ago, he complained of progressive hearing loss and increased tinnitus again. Six months ago he complained of a sudden severe hearing loss along with vertigo. We operated on his left ear to replace a Teflon piston and performed stapedotomy in his right ear and the vertigo was disappeared. The patient's daughter, 38 years old, complained of unilateral hearing loss and vertigo attacks, and suffered from bone fracture several times in her childhood.
In this case caloric response was diminished to a greater degree in his left ear than that of his right ear. A glycerol test showed positive in the left ear. The results of otoneurologic studies suggested that endolymphatic hydrops caused vertigo and sudden hearing loss in this patient.

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