Deiters' cells in the organ of Corti possess gap junctions that contribute to the K recycling system in the cochlea. Among the supporting cells, Deiters' cells are in close contact at the apical pole and at the basal pole to the outer hair cells, so Deiters' cells play an important role in the K recycling system. We studied the properties of K currents in isolated Deiters' cells from guinea-pig cochlea. Deiters' cells were isolated by trypsin and mechanical triturations, and could be identified by those morphologic characteristics. The K currents were measured by the conventional mode of patch electrode voltage-clamp technique. In standard extracellular solutions, voltage steps in the negative direction yielded very small currents while steps in the positive direction yielded very large currents, suggesting properties of outward rectification. The conductance of peak currents at +100mV was 26.2 nS. The currents demonstrated a fast activation (within 10 ms) and slower inactivation (in the range of seconds). Temperature-dependence of K current kinetics was evaluated by comparing that at room temperature with that at 36°C The amplitude of K currents increased at 36°C and both the rates of activation and inactivation increased at 36°C. Q10 of the activation rate was 1.78 and that of inactivation was 1.51.

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The use of cartilage in middle ear surgery is not new, and already utilized in various indications such as retraction pockets, recurrent perforations and atelectatic ears. We concluded that thinly sliced cartilage was very useful for middle ear surgery when inflammatory adhesion was present, and this cartilage has good conductive efficiency and shape retention. We reviewed all chart of patients who underwent tympanoplasty using thinly sliced cartilage retrospectively at Tottori University from 2005 to 2008. At the end of surgery, a piece of cartilage was harvested and then thinly sliced by using a cartilage slicer. This cartilage was then introduced over the adhesive area in the middle ear cavity and also used to reconstruct the posterior canal wall. For the procedure to be successful, the graft needed to be placed on the malleus handle. Post-operative hearing result was obtained by comparing the pre- and postoperative pure-tone audiometry (PTA), with the average postoperative period of six months.

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One hundred twenty-five cases of tympanoplasty in our department were evaluated between February 2004 and November 2007. Postoperative hearing results were analyzed according to types of disease, methods of surgery, and the results were classified using the criteria suggesting by the Japan Otological Society Committee in 2000. Successful result was obtained in 29 of 34 ears (85%) with tympanoplasty type I, in 55 of 73 ears (77%) with tympanoplasty type III, 13 of 18 ears (72%) with tympanoplasty type IV. And also favorable hearing results were observed in 74% of the patients who underwent III-i, 82% of III-c, 75% of IV-i, and 70% of IV-c. There was no significant difference in the postoperative hearing results between chronic otitis media and middle ear cholesteatoma. Staged tympanoplasty was performed in 29 ears of the 78 with cholesteatoma, and showed excellent success with type IV.

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Turner syndrome is a chromosome disorder in female, and they often have otic complications such as sensorineural hearing loss, auricular malformations and recurrent otitis media. In Japan, however, there were few reports regarding these otic complications in this syndrome. We presented a case of 46-year-old woman who has a progressive hearing loss. Her chief complaints were vertigo and hearing loss, and then her hearing loss has deteriorated after hysterectomy and ovariectomy.
Some recent studies suggested that estrogens may influence the hearing functions. In this case, her hearing deterioration after ovariectomy made us considered that decreasing levels of estrogens was one of the causes of her hearing loss.

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The Bone Anchored Hearing Aid - Baha® - is today a well establish treatment option in selected patients with hearing impairment.
In this review article we will present the concept of osseointegration which is the prerequisite for the Baha®. The traditional indications are chronic ear disease, bilateral ear canal atresia, unilateral conductive hearing loss in only hearing ear and external ear canal problems that can not tolerate an air conduction hearing aid mould. Bilateral fitting and patient with single sided sensori neural deafness and Baha® in children will also be discussed. A short description of the surgical procedure is given. A extensive reference list will provide the interested reader with literature from colleagues experienced in the area of direct bone conduction via B Baha®.

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Endoscopic observation and treatment have been remarkably developed in so many fields of the medicine, because they are very clear to observe local disease and no traumatic. In Otolaryngology, what is the reason that endoscopic application is very popular in rhinology and unpopular in otology? Working space may be important factor for limited use of endoscope in narrow external ear canal and middle ear. Another reason may be difficult operative skill to introduce an endoscopic ear surgery.
Our ear surgeon holds an endoscope with 2.7 mm diameter and 17 cm long in the left hand and handles surgical tools in the right hand. Both two devices are introduced into the middle ear through the external ear canal.
Merit of endoscopic-aided ear surgery is that its observation can give a full and clearly view of the middle ear cleft. Detailed observation can avoid an injury of the facial nerve or the inner ear. Moreover, endoscope can show a residual cholesteatoma under the ossicles or in the tympanic sinus which lesion might not be found with a microscopic observation. Therefore, an endoscope should be introduced more and more for ear surgery, especially in case of children. The anatomical feature may cause ear surgeon to hesitate the use of an endoscope in children. We have performed an endoscope-aided ear surgery in children for the last three years and endoscope was possible to apply for safe operation in every case of children.
Our conclusion is that endoscope should be used more in daily ear clinic for accurate diagnosis of ear disease and in ear surgery for safe operation with full view of middle ear cavity and to avoid residual disease.

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Organs which otolaryngology cover, and a respiratory system can be caught with the concept of one airway. Incorrect swallowing of the secretion of a nasal cavity and the pharynx are main courses to which a pathogenic organ reaches to lungs. In addition, the three major infecting organisms of acute otitis media are Haemophilus influenzae, Streptococcus penumoniae, and Staphylococcus aureus. These three major infecting organisms are the same as the three major infecting organisms of the secondary bacterial pneumonia which merges from influenza virus infection. Moreover, S. penumoniae and H. influenzae are important as an infecting organism of upper respiratory tract infection and pneumonia which is the infection of alveoli located in the end of airway. It becomes possible to apply the knowledge (especially trend of resistant bacteria) acquired from this by respiratory tract infection to otolaryngology infection. Since S. penumoniae are main infecting organisms also in otolaryngology organ infection, when choosing new quinolones, it is necessary to certainly choose respiratory quinolones.

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Ménière's disease is a disorder characterized by hearing loss, tinnitus and disabling vertigo. A common pathogenetic factor is the disturbance of endolymphatic and perilymphatic osmotic and hydrostatic pressure due to defined etiologies or idiopathic attacks. The current diagnostic criteria base the diagnosis of Ménière disease on the clinical presentation alone. However, most otolaryngologists request a widened instrumental evaluation of patients suspected of Ménière disease. Recently, new and more sophisticated diagnostic tests have been developed both in audiovestibulology i.e. dehydration test and in imaging, i.e. high resolution MRI.
The homeostasis of water in the inner ear is essential for maintaining the function of hearing and equilibrium. It is well known that water homeostasis of the inner ear is regulated in part via the arginine vasopressin (AVP)-AQP2 system in the same fashion as in the kidney, and endolymphatic hydrops is thought to be caused by mal-regulation of this system. Therefore, AVP appear to be important for the development of novel therapies for Ménière's disease and related disorders. AVP is also well known as a stress hormone influencing the hypothalamo-pituitary-adrenal axis (HPA axis) via V2 receptor. Recent studies suggested that stress management might be effective for preventing both the development and progression of Ménière's disease.
In this article, the current status of diagnosis and treatment of Ménière's disease are documented and discussed.

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