Tetsuya Tono

Miyazaki University, Miyazaki-shi, Miyazaki-ken, Japan

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Publications (23)21.52 Total impact

  • Article: Pathogenic substitution of IVS15 + 5G > A in SLC26A4 in patients of Okinawa Islands with enlarged vestibular aqueduct syndrome or Pendred syndrome.
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    ABSTRACT: BACKGROUND: Pendred syndrome (PS) and nonsyndromic hearing loss associated with enlarged vestibular aqueduct (EVA) are caused by SLC26A4 mutations. The Okinawa Islands are the southwestern-most islands of the Japanese archipelago. And ancestral differences have been reported between people from Okinawa Island and those from the main islands of Japan. To confirm the ethnic variation of the spectrum of SLC26A4 mutations, we investigated the frequencies of SLC26A4 mutations and clinical manifestations of patients with EVA or PS living in the Okinawa Islands. METHODS: We examined 22 patients with EVA or PS from 21 unrelated families in Okinawa Islands. The patient's clinical history, findings of physical and otoscopic examinations, hearing test, and computed tomography (CT) scan of the temporal bones were recorded. To detect mutations, all 21 exons and the exon--intron junctions of SLC26A4 were sequenced for all subjects. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) for SLC26A4 and calculations using the comparative CT (2-DeltaDeltaCT) method were used to determine the pathogenicity associated with gene substitutions. RESULTS: SLC26A4 mutations were identified in 21 of the 22 patients. We found a compound heterozygous mutation for IVS15 + 5G > A/H723R in nine patients (41%), a homozygous substitution of IVS15 + 5G > A in six patients (27%), and homozygous mutation for H723R in five patients (23%). The most prevalent types of SLC26A4 alleles were IVS15 + 5G > A and H723R, which both accounted for 15/22 (68%) of the patients. There were no significant correlations between the types of SLC26A4 mutation and clinical manifestations. Based on qRT-PCR results, expression of SLC26A4 was not identified in patients with the homozygous substitution of IVS15 + 5G > A. CONCLUSIONS: The substitution of IVS15 + 5G > A in SLC26A4 was the most common mutation in uniquely found in patients with PS and EVA in Okinawa Islands. This suggested that the spectrum of SLC26A4 mutation differed from main islands of Japan and other East Asian countries. The substitution of IVS15 + 5G > A leads to a loss of SLC26A expression and results in a phenotype of PS and EVA.
    BMC Medical Genetics 05/2013; 14(1):56. · 2.33 Impact Factor
  • Article: [Audiometric findings of senior high school students belonging to a Kendo Club].
    Eiji Kato, Tetsuya Tono
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    ABSTRACT: Between 1992 and 2010, we studied audiometric findings obtained from the annual hearing examination for senior high-school students who belonged to an active Kendo team. The subjects comprised 140 males and 88 females with ages between 15 and 18 years. The pure tone audiometry showed that 69 ears of 45 students (19.7%) had sensorineural hearing loss with the highest threshold shift at 2000 Hz, followed by 4000 Hz. Frequent audiometric patterns included a 2000 Hz-dip, a 4000 Hz-dip and a combined loss of 2000 and 4000 Hz. Some of these affected subjects had shown a completely normal audiogram at the previous examination. Moreover, small-dips with a depth less than 25 dB were found to be limited either at 2000 Hz or at 4000 Hz, suggesting early audiometric changes from a temporary or a permanent threshold shift caused by noise and/or head blows during Kendo practice. The incidence of such abnormal audiograms among this Kendo club members appears to be decreasing year by year owing to the annual check-ups over the 18-year study period, and student counseling regarding the possible adverse effect of Kendo on the inner ear function.
    Nippon Jibiinkoka Gakkai Kaiho 09/2012; 115(9):842-8.
  • Article: [A case of propranolol therapy for infantile capillary hemangiomas of the parotis].
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    ABSTRACT: A 4-month-old healthy female infant presented with rapid onset of subaural swelling over a three-month period. A head and neck exam demonstrated a subaural elastic hard mass with a red birthmark below the left auricle. MRI of the neck demonstrated a well-defined parotid mass consistent with a haemangioma. We treated this infant with 1 mg/kg of propranolol, which was gradually increased over two months to a dose of 2 mg/kg daily. The tumor began to reduce in size within three days after drug administration, and became less prominent in one month, and had almost totally disappeared within four months. On ten-month follow-up, the patient was asymptomatic and repeated MRI demonstrated further regression of the tumor. Propranolol could be the first-line choice for treating haemangioma rather than simple
    Nippon Jibiinkoka Gakkai Kaiho 06/2012; 115(6):632-5.
  • Article: [Multicenter clinical study of bone-anchored hearing aids in Japan--application for congenital auricular atresia].
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    ABSTRACT: The effectiveness of bone anchored hearing aid (BAHA) for the patients with congenital aural atresia was evaluated by multicenter clinical study in Japan. Twenty patients (17 bilateral and 3 hemilateral) of congenital auricular atresia were registered for this study and finally, 18 of them (15 bilateral and 3 unilateral) were subjected to further evaluation. Primary endpoint of this study was free sound-field pure-tone audiometory and speech threshold hearing test in quiet and noisy circumstances. Secondary endpoint of this study was patient's satisfaction based upon APHAB (Abbreviated Profile of Hearing Aid Benefit) questionnaire survey. These results were compared between before and 12 weeks after BAHA surgery. Both hearing level of pure tone and speech threshold significantly improved after BAHA surgery. APHAB scores also suggested the improvement of the QOL after BAHA usage, except for the scores that concerned with unpleasantness of noisy sound. BAHA is one of the useful options for the treatment of congenital auricular atresia.
    Nippon Jibiinkoka Gakkai Kaiho 09/2011; 114(9):761-7.
  • Article: Incidence of external auditory canal exostoses in competitive surfers in Japan.
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    ABSTRACT: The objective of this study was to demonstrate the prevalence and severity of external auditory canal exostoses in a population of competitive surfers in Japan. The authors used a “surfing index,” the product of the period (years) as an active surfer and the frequency (number of surfing days per week), to predict external auditory exostoses formation. Cross-sectional study. A total of 5 surfing competitions that were held in Miyazaki, Japan. The ear canals of 373 surfers with an average age of 33.1 years (range, 11-80 years) were examined with an otoscope. The severity of exostosis was classified into 4 groups, ranging from grade 0 to 3, according to otoscopic findings. Subjects also completed a questionnaire detailing their surfing habits. There was a 59.8% overall prevalence of exostoses in 373 surfers. The incidences of grade 1, 2, and 3 exostoses were 118 (31.6%), 71 (19.0%), and 34 (9.1%), respectively. The prevalences of grade 2 and 3 exostoses were higher in surfers with a surfing index of more than 20 (P < .0001). The authors determined that a positive association exists between the surfing index and the severity of exostoses. The findings suggest that it is possible to assume the likelihood of exostosis formation from the surfing index, and this may be of help to spread awareness of exostosis among surfers.
    Otolaryngology Head and Neck Surgery 03/2011; 145(1):80-5. · 1.72 Impact Factor
  • Article: Neuro-otological findings in psychiatric patients with nystagmus.
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    ABSTRACT: To evaluate whether neuro-otological tests have clinical significance in psychiatric patients with nystagmus who have inner ear and/or brain dysfunction, we performed neuro-otological tests on 56 psychiatric patients with nystagmus (38 men, 18 women) (age range 40-97; mean age ± SD 61.6 ± 10.5 years). Patients were classified according to the underlying diseases: schizophrenia (25 cases), organic psychiatric disorders (14 cases), alcoholism (16 cases) and excited mental retardation (1 case). Caloric test results showed a normal response in 30 (75%) cases, right canal paresis (CP) in 4 (10%), left CP in 4 (10%) and bilateral CP in 2 (5%). Therefore, 10 (25%) cases had CP. The results of the eye tracking tests (ETT) were sorted into five categories: 4 (8.2%) cases smooth (normal), 8 (16.3%) slightly saccadic, 28 (57.1%) saccadic, 8 (16.3%) ataxic, and 1 (2%) no tracking ability. Therefore, 45 (91.8%) cases had abnormal ETT results. Pure tone audiometry showed normal hearing in 24 (47.1%) cases, right hearing loss (HL) in 3 (5.8%), left HL in 3 (5.8%) and bilateral HL in 21 (41.2%). Therefore, 27 (52.9%) cases had HL. The patients were classified as organic or functional groups. In ETT there was a significant difference between these two groups. These results indicate that neuro-otological tests with video-oculography are very important not only for neurological or neuro-otological patients with nystagmus, but also for psychiatric patients with nystagmus.
    Archives of Oto-Rhino-Laryngology 03/2011; 268(12):1713-9. · 1.29 Impact Factor
  • Article: Efficacy of diffusion-weighted magnetic resonance imaging in the diagnosis of middle ear cholesteatoma.
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    ABSTRACT: This study evaluated the usefulness of diffusion-weighted magnetic resonance imaging (DWI) in the diagnosis of middle ear cholesteatoma. We performed DWI on 73 patients suspected of having middle ear cholesteatoma, including 21 revision cases. Magnetic resonance imaging was performed with 1.5T units using diffusion-weighted spin-echo-type echo planar imaging (DWI). Of 73 subjects, 59 had cholesteatoma that consisted of 41 primary acquired cholesteatoma, 13 had residual and/or recurrent cholesteatoma, four had congenital cholesteatoma, and one had iatrogenic cholesteatoma. Positive DWI findings were observed in 42 subjects and negative findings in 31 subjects. The sensitivity, specificity, and positive and negative predictive values of DWI for cholesteatoma were 69.4%, 92.8%, 97.5%, and 41.9%, respectively. In the case of 34 patients who were positive for cholesteatoma on both otoscopic and CT examinations, 33 were diagnosed with cholesteatoma. Of the remaining 39 subjects with one or both negative results for cholesteatoma, the sensitivity, specificity, positive predictive value, and negative predictive value of DWI were 57.6%, 92.3%, 93.7%, and 52.1%, respectively. Cholesteatoma mass diameters were less than 5mm in 10 out of 18 subjects with both cholesteatoma and negative DWI findings. Of the 21 subjects who received revision surgery, the sensitivity, specificity, and positive and negative predictive values of DWI for residual or recurrent acquired cholesteatoma were 71.4%, 100%, 100%, and 63.6%, respectively. Since DWI clearly showed high specificity and positive predictive value, it is useful for diagnosing middle ear cholesteatoma, including postoperative recurrent cholesteatoma of 5mm diameter or larger. DWI could sufficiently detect cholesteatoma with one or both negative results on otoscopic and CT examinations, but it was difficult to detect cholesteatoma of less than 5mm diameter using DWI owing to the tiny mass and small volume of debris.
    Auris, nasus, larynx 01/2011; 38(3):329-34. · 0.58 Impact Factor
  • Article: Ossiculoplasty with a cartilage-connecting hydroxyapatite prosthesis for tympanosclerotic stapes fixation.
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    ABSTRACT: Many cases of tympanosclerotic stapes fixation are accompanied by fixation or erosion of malleus and/or incus. This status of the ossicular chain is one of the reasons that ossiculoplasty for tympanosclerotic stapes fixation is more difficult than that for otosclerosis. We conducted a retrospective review of seven patients who were operated on for tympanosclerotic stapes fixation between 2002 and 2006. All of the patients had abnormal conditions of the malleus and/or incus and underwent stapedectomy and total ossiculoplasty with hydroxyapatite prosthesis (Apaceram T-7 type), which has a planar-like head portion that contacts a piece of cartilage. Postoperative hearing results were assessed in all seven patients after at least 1 year. The postoperative air-bone gap (ABG) was closed within 10 dB in two of seven patients, and was less than 20 dB in six of seven patients. The mean postoperative ABG was closed within 10 dB at 1 and 2 kHz and less than 20 dB at low frequencies (0.25 and 0.5 Hz). There was almost no hearing improvement at high frequencies (4 and 8 kHz). There were no patients with postoperative sensorineural hearing loss. The present study shows that stapedectomy and total ossiculoplasty with cartilage-connecting hydroxyapatite prosthesis is effective and safe for stapes fixation accompanied by fixation or erosion of the malleus and/or incus.
    Archives of Oto-Rhino-Laryngology 11/2009; 267(6):875-9. · 1.29 Impact Factor
  • Article: Nystagmus using video-oculography in psychiatric patients.
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    ABSTRACT: To evaluate whether nystagmus has clinical significance in psychiatric patients who have functional and/or organic brain dysfunction. We performed gaze, positional and positioning nystagmus tests on 227 patients with psychiatric diseases (144 men, 83 women, with an average age +/- SD of 62.5 +/- 14.0 years) in order to evaluate the frequency and characteristics of nystagmus. Patients were classified according to the underlying disease. Normal control subjects were 107 subjects (26 men, 81 women, with an average age +/- SD of 35.6 +/- 10.0 years). Nystagmus was observed in 56 (24.7%) of 227 cases. Nystagmus was seen in 16 (59.3%) of 27 cases of alcoholism, 14 (22.2%) of 63 cases of organic psychiatric disorders, 25 (20.2%) of 124 cases of schizophrenia, 1 (20.0%) of 5 cases of excited mental retardation, 0 (0.0%) of 7 cases of mood disorders, 0 (0.0%) of 1 case of anxiety disorders and 1 (0.9%) of 107 subjects of normal control. There was a significant difference between psychiatric diseases and normal control. These results indicate that nystagmus may also be a very important clinical finding not only in patients with neurological and neuro-otological diseases, but also in patients with psychiatric diseases.
    Archives of Oto-Rhino-Laryngology 12/2008; 266(8):1167-74. · 1.29 Impact Factor
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    Article: Proteasomal degradation of IRS-2, but not IRS-1 by calcineurin inhibition: attenuation of insulin-like growth factor-I-induced GSK-3beta and ERK pathways in adrenal chromaffin cells.
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    ABSTRACT: The ability of calcineurin to regulate IRS-1 and IRS-2 levels has not been examined in any given cells, although calcineurin inhibition by therapeutic immunosuppressants produced cytoprotective and cytotoxic effects (e.g., new-onset of diabetes mellitus, seizure). Chronic (>or=3h) treatment of cultured bovine adrenal chromaffin cells with cyclosporin A or FK506 decreased IRS-2 protein level by approximately 50% (IC(50)=200 or 10nM), without changing IRS-2 mRNA level, and insulin receptor, insulin-like growth factor-I (IGF-I) receptor, IRS-1, PI3K/PDK-1/Akt/GSK-3beta and ERK1/ERK2 protein levels. When the cells were washed to remove the test drug, the decreased IRS-2 level restored to the control level. Cyclosporin A or FK506 treatment inhibited calcineurin activity (IC(50)=500 or 40 nM, in vitro assay). Rapamycin, an FK506-binding protein ligand unable to inhibit calcineurin, failed to decrease IRS-2, but reversed FK506-induced decreases of calcineurin activity and IRS-2 level. Pulse-label followed by polyacrylamide gel electrophoresis revealed that cyclosporin A or FK506 accelerated IRS-2 degradation rate (t(1/2)) from >24 to approximately 4.2h, without altering IRS-2 synthesis. IRS-2 reduction by cyclosporin A or FK506 was prevented by lactacystin (proteasome inhibitor), but not by calpeptin (calpain inhibitor) or leupeptin (lysosome inhibitor). Cyclosporin A or FK506 increased serine-phosphorylation and ubiquitination of IRS-2. Cell surface (125)I-IGF-I binding capacity was not changed in cyclosporin A- or FK506-treated cells; however, IGF-I-induced phosphorylations of GSK-3beta and ERK1/ERK2 were attenuated by approximately 50%, which were prevented by rapamycin or lactacystin. Thus, calcineurin inhibition decreased IRS-2 level via proteasomal IRS-2 degradation, attenuating IGF-I-induced GSK-3beta and ERK pathways.
    Neuropharmacology 08/2008; 55(1):71-9. · 4.81 Impact Factor
  • Article: [Value of diffusion-weighted MR imaging in the detection of middle ear cholesteatoma].
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    ABSTRACT: This study, was conducted to determine the clinical value of diffusion-weighted MR imaging (DWI) in detecting the presence of cholesteatoma. Fifty-six patients (21 female and 35 male patients; mean age, 43 years) who underwent middle ear surgery were referred to the radiology department for a preoperative DWI study. DWI depicted 41 out of 48 cholesteatomas involving the middle ear cavity (sensitivity, 85.4%). Seven patients with middle ear cholesteatoma who showed negative DWI findings (false-negative cases) had limited keratin accumulation due to simple atelectasis or meticulous evacuation of keratin debris before the MRI study. No falsepositive cases were found in this study (specificity, 100%). The positive predictive value and negative predictive value were 100% and 53.3%, respectively. The minimum size of middle ear cholesteatoma detected by the current MRI system was 5mm. Diffusion-weighted MR imaging was useful for the detection of middle ear cholesteatoma.
    Nippon Jibiinkoka Gakkai Kaiho 12/2007; 110(11):707-12.
  • Article: Involvement of Epstein-Barr virus (EBV)-encoded latent membrane protein (LMP)-1 in the potentiation of C epsilon mRNA expression in human tonsil-derived cells.
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    ABSTRACT: The aim of our study was to investigate a possible correlation between Epstein-Barr virus (EBV) infection status, including its latent gene expression, and expression of allergy-related genes in human tonsil-derived cells. In the tonsil-derived cells from the patients undergoing routine tonsillectomies for palatine tonsil hypertrophy or tonsillar focal infection, the presence of EBV DNA and mRNA expressions of latent membrane protein (LMP)-1, C epsilon chain, and activation-induced cytidine deaminase (AID) were detected by PCR and RT-PCR analysis, respectively. Of all the 12 patients, PCR products amplified from EBV DNA BamHI W fragment were detected in the tonsils from the 10 patients (83.3%). LMP1 mRNA expressions were confirmed in the six patients (50%). Both LMP1 mRNA expressions and EBV DNA were detected in the five patients. EBV DNA, but not LMP1 mRNA expression, was detected in the five patients. LMP1 mRNA expression, but not EBV DNA, was detected in one patient. In one patient, neither EBV DNA nor LMP1 mRNA expression was confirmed. C epsilon mRNA expressions were confirmed in all the 12 patients along with AID mRNA expressions. The degree of C epsilon mRNA expression, however, varied with the patients. The Fisher's exact probability test revealed a statistically significant correlation between LMP1 and C epsilon gene expressions, indicating that C epsilon mRNA expression level was significantly higher in the LMP1 positive samples than in the negative samples. On the other hand, there was no significant correlation between AID and LMP1 mRNA expressions. Thus, EBV infection is a notable factor capable of exacerbating allergic inflammation.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 04/2007; 264(3):245-50. · 1.29 Impact Factor
  • Article: Preservation of the auditory nerve function after translabyrinthine removal of vestibular schwannoma.
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    ABSTRACT: To evaluate the function of the postoperative auditory nerve preserved after translabyrinthine (TL) vestibular schwannoma (VS) removal. Fifteen patients, who underwent unilateral VS resection via a TL approach, were preserved auditory nerve anatomically. The size and location of VS were measured on MRI preoperatively. After surgery, the electrical stimulation test (EST) or electrically evoked auditory brainstem response (EABR) was performed. Four cases (27%) out of fifteen patients were retained the functional integrity of the auditory nerve after surgery. The maximum tumor size in the group with a positive response to EST or EABR was significantly smaller than that in the group with a negative response to EST. It seems to be difficult to preserve auditory nerve function in cases where a tumor extends to the fundus of internal auditory canal. These results suggest that size of tumor and/or extension of tumor to the fundus might be important factors in preserving the auditory nerve function even if using a TL approach.
    Auris Nasus Larynx 04/2006; 33(1):7-11. · 0.76 Impact Factor
  • Article: Relationship of intraoperative and postoperative electrically evoked stapedius reflex threshold and comfort level in cochlear implant patients.
    Cochlear Implants International 10/2004; 5 Suppl 1:32-3.
  • Article: Correlation of CT analysis and audiometry in Japanese otosclerosis.
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    ABSTRACT: To determine the extent of audiometric correlation with CT findings. Forty-four patients (82 ears) with surgically confirmed otosclerosis underwent preoperative CT examination. Based on the computed tomography (CT) findings, the ears were classified into five groups as follows: Group A, the group with no pathological CT findings; Group B1, the group with demineralization localized in the region of the fissula antefenestram; Group B2, the group with demineralization extending towards the cochleariform process from the anterior region of the oval window; Group B3, the group with extensive demineralization surrounding the cochlea; and Group C, the group with thick anterior and posterior calcified plaques. There were 32 ears (39.0%) in Group A, 21 ears (25.6%) in Group B1, 16 ears (19.5%) in Group B2, 7 ears (8.5%) in Group B3, and 6 ears (7.3%) in Group C. The mean bone conduction levels were greater in the order of the extent of demineralization: Groups A, B1-B3 suggesting positive relationship between the cochlear function and the degree of labyrhinthine otosclerosis. A good correlation between the preoperative CT findings and audiometry findings suggests that CT with a slice intervals between 0.5 and 1mm could provide useful informations in assuming the extent of otosclerosis in the inner ear.
    Auris Nasus Larynx 07/2004; 31(2):125-9. · 0.76 Impact Factor
  • Article: Effect of single-drug treatment on idiopathic sudden sensorineural hearing loss.
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    ABSTRACT: In order to evaluate the effect of a medical administration for the sudden deafness patients, single-drug treatment for idiopathic sudden sensorineural hearing loss (ISSHL) was assessed at multi-centers participating in the Acute Severe Hearing Loss Study Group sponsored by the Ministry of Health, Labor and Welfare of Japan. The subjects consisted of ISSHL patients who were (1) 20 years of age or older, (2) diagnosed within 2 weeks after the onset of hearing loss, (3) showing a mean hearing level of 40-90 dB at five frequencies from 250 to 4000 Hz, (4) previously untreated, and (5) with normal for age in hearing of the opposite ear. The drugs used in this study were ATP, alprostadil, hydrocortisone and amidotrizoate, which were administered intravenously, and beraprost sodium and betamethasone, which were given orally. Two drugs were assigned to each center, one of which was selected according to the code hidden in envelopes and administered for 1 week. The treatment after the single-drug administration was conducted at the discretion of each center. The hearing gain and recovery rate at 1 week after the initiation of single-drug treatment and at 1 month or over when the hearing level was fixed, were evaluated based on the criteria for hearing recovery prepared by the Acute Severe Hearing Loss Study Group. There was no statistically significant difference in the recovery rate among drugs either at 1 week after the initiation of single-drug treatment or at the time of fixed hearing level. At the time when the hearing level was fixed, a statistically significant difference in the complete recovery rate was detected only between amidotrizoate and beraprost sodium. From these results, we could not find any specific drugs recommended for ISSNHL. In evaluating the effect of the drugs, however, several problems in the clinical trial for ISSHL should be considered.
    Auris Nasus Larynx 06/2003; 30(2):123-7. · 0.76 Impact Factor
  • Article: [A case of enlarged vestibular aqueduct syndrome with PDS gene mutations].
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    ABSTRACT: Enlarged vestibular aqueduct (EVA) is an inner ear anomaly occasionally associated with sensorineural hearing loss (SNHL) and/or dizziness. Recent genetic studies indicate that mutations in the PDS gene may cause EVA. A 10-year-old EVA patient who had undergone annual hearing tests for 7 years had an aunt and cousin who also had hearing loss and EVA, so genetic examinations were conducted for a possible genetic link. Two new PDS gene mutations, S610X and S657N, were found in all 3, including the proband. We discuss the importance of genetic analysis, which offers new insight into SNHL diagnosis and treatment in children.
    Nippon Jibiinkoka Gakkai Kaiho 03/2002; 105(2):174-7.
  • Article: Stapes Ankylosis in an Autosomal-Dominant Inherited Syndrome
    Ontology & Neurotology 04/2001; 22(3):417. · 1.90 Impact Factor
  • Article: Different Clinical Characteristics of Aminoglycoside-Induced Profound Deafness with and without the 1555 A→G Mitochondrial Mutation
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    ABSTRACT: Recent genetic studies have shown that hereditary susceptibility to aminoglycoside antibiotics is caused by the 1555 A→G mitochondrial mutation. We found the 1555 mutation in 4 out of 68 postlingual deaf patients who were candidates for cochlear implantation. All 4 patients developed bilateral profound hearing loss following administration of aminoglycosides. The pedigree of the family shows exclusively maternal transmission of hearing impairment in each case. On comparison with neuro-otological findings from aminoglycoside-induced deaf patients without the 1555 mutation, four distinct characteristics were noted: (1) a progressive nature of hearing loss; (2) better residual pure-tone thresholds; (3) lower thresholds for electrical promontory stimulation, and (4) well-preserved vestibular function. Although other factors such as differing dosages and/or administration routes may also be involved, profound hearing loss associated with the 1555 mutation may be due to a different pathogenic mechanism, i.e., strial dysfunction rather than a direct insult to the hair cells.
    ORL 08/1970; 63(1):25-30. · 0.91 Impact Factor
  • Article: High potassium-induced glutamate release in the cochlea : in vivo microdialysis study combined with on-line enzyme fluorometric detection of glutamate
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    ABSTRACT: http://www.elsevier.com/wps/find/journaldescription.cws_home/622287/description

Institutions

  • 2004–2012
    • Miyazaki University
      • Department of Otorhinolaryngology
      Miyazaki-shi, Miyazaki-ken, Japan
    • University of Ryukyus
      • Faculty of Medicine
      Okinawa, Okinawa-ken, Japan