Twenty four cholesteatoma cases, with hearing within 20dB at three averaged speech frequencies, were operated on from 1998 to 2004. Their mean age was 26.6 years, and the mean follow-up period 31.7 months. Two cases were congenital cholesteatoma, 16 cases pars flaccid type, 4 cases pars tensa type, and 2 cases secondary acquired cholesteatoma.
They were operated on by tympanoplasty without mastoidectomy (4 cases), canal wall up method (3 cases), canal wall up method and scutumplasty (2 cases), canal wall down method with canal reconstruction and mastoid obliteration (6 cases), canal wall down method with canal reconstruction (4 cases), and canal wall down method (5 cases).
One case (4.0%) operated by the canal wall up method and scutumplasty had recurrence of cholesteatoma and the patient underwent revision surgery by canal wall down method. Four cases (16.7%) showed a retraction of the pars flaccid. Postoperative hearing results were within 30dB in 17 cases (70.8%). Probability of postoperative hearing gain within 20 dB in seven cases with ossicular chain disruption by cholesteatoma was lower than in the cases with normal ossicular chain.
These findings encouraged us to operate on choleteatoma cases with normal hearing and to recommend the operation to the patients carefully by the informed consent.

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Sixteen infants and children who were referred from affiliated hospitals to us were investigated in this study. They showed absence or threshold elevation of ABR at the first examination were improved or normalized after the follow-up examination. ABRs in 19 of 27 ears were improved and 8 of 27 ears were normalized. The significant prolongation of ABR waves were found at the latency of wave I, III, V, but no prolongation of wave I-V latency was found. The pathophysiology of normalization of wave I, must be caused by middle ear problems. The mixed hearing losses in our cases must be caused by delayed myelination of auditory brainstem system or lower firing synchrony of nerve.

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We report 6 cases of Japanese fencing players with sensorineural hearing loss associated in fencing, Kendo. Kendo-associated hearing loss is characterized by notch at 2000Hz, at 4000Hz and both. The hearing loss at 2000Hz initially was reversible, and then became permanent. On the contrary, the hearing loss at 4000Hz is induced by repeated exposure to loud noise(about 120dB)at beating a kendo mask by a bamboo sword. It is also suggested that the hearing loss at 2000Hz is induced by concussion of the inner ear with vibration of the head at a peak frequency of 2000Hz when a bamboo sword beats a kendo mask. Independent appearance and progression of 4000Hz and 2000Hz notches manifest the variety of hearing loss patterns associated with Kendo.

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An enlarged vestibular aqueduct, high frequency hearing loss, and fluctuating hearing loss are characteristics of enlarged vestibular aqueduct syndrome. Causes of fluctuating hearing loss include contusion or extreme movement of the head. In addition, mutations in the PDS gene have been reported as responsible for this condition.
Case 1 began to have fluctuating hearing loss after a contusion in September 1999.After a decrease in hearing ability in the right ear in July 2001, recovery was not seen. However, two years and four months later, hearing recovery occurred suddenly.
Case 2 began to have fluctuating hearing loss after a school athletic event in May 1998. After a decrease in hearing ability in the left ear in July 2003, immediate recovery was not seen but hearing was regained gradually over an eight-month period. Hearing loss was seen in the right ear in November 2004 and recovery occurred four months later.
Fluctuating hearing is thought to be caused by the backward flow of low potassium fluid from the endolymphatic sac, following a sudden increase in pressure on the brain. The lowered potassium of the endolymphatic fluid contributes to a lowered endocochlear potential that causes the hearing impairment. On the other hand, it has been reported that in PDS gene knockout mouse, the expression of KCNJ 10, which is a potassium channel in the stria vascularis, is lacking and there is a markedly lowered voltage of endocochlear potential, suggesting that the inhibition of KCNJ10 is involved in hearing loss. Accordingly, the current two cases, in which long-term hearing impairment gradually or suddenly recovered, suggest that acute hearing impairment is not due to damage of the hair cells.

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We report a case of congenital adhesion and fixation of the malleus and incus associated with deformity of the stapes superstructure in a 39-year-old man. He had a right auricular malformation (so-called cupped ear) and an ectopic handle of the right malleus without deformity of the external auditory meatus. He complained of hearing impairment on the right side. Pure tone audiometry showed conductive hearing loss of 63.3dB in the right ear. Computed tomography suggested deformity and fixation of the head of the malleus and body of the incus in the right tympanic cavity. Exploration of the right middle ear was performed and the following anomalies were observed: 1) osseous adhesion between the head of the malleus and the body of the incus with formation of the coalescence bone, 2) osseous fixation of the malleus/incus coalescence bone to the lateral wall of the tympanic cavity, and 3) severe deformity of the long process of the incus and the superstructure of the stapes. Fixation of the stapes was not observed. Removal of the bony tissue causing fixation of the malleus/incus coalescence bone was performed, and mobilization of all the ossicles was achieved while keeping the ossicular chain intact. Hearing improvement of 43dB was obtained.
It was speculated that the anomalies were due to abnormal development of the first and second branchial arches at 6 to 7 weeks of the embryonic life.
For classification of auditory ossicle malformations without associated abnormalities of the external auditory meatus, we should not only evaluate discontinuity or fixation of the ossicles but also the extent of deformity.

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