Search

Background: Delayed endolymphatic hydrops (DEH) is an inner ear disease that causes recurrent vertigo in the ipsilateral ear or fluctuating hearing in the contralateral ear due to endolymphatic hydrops secondary to preceding deafness. There are few reports of large, multicentre studies investigating the clinical-epidemiological characteristics of DEH., Objective: This study aimed to clarify the characteristics of DEH in Japan., Methods: Clinical data on 662 patients with DEH were analysed by nationwide, multicentre surveys conducted by the Peripheral Vestibular Disorders Research Group of Japan., Results: The proportion of ipsilateral DEH (IDEH) was slightly higher than that of contralateral DEH (CDEH) at 55.4%. The time delay between onset of precedent deafness and onset of DEH was significantly longer for CDEH than for IDEH. The most common cause of precedent deafness was a disease of unknown cause with onset in early childhood (33.1%). Epidemiological characteristics were not significantly different between CDEH with and without vertigo., Conclusion: DEH appearing to be caused by viral labyrinthitis has a high rate of onset within 40 years of precedent deafness. Clinical and epidemiological characteristics of IDEH, CDEH with vertigo, and CDEH without vertigo were very similar., Significance: The clinical-epidemiological characteristics of DEH in Japan were clarified.

Conclusions: The majority of hearing loss due to mumps presents as unilateral profound sensorineural hearing loss, which is refractory to treatment. In rare cases of bilateral total deafness, cochlear implants were beneficial for speech perception. Vaccination against mumps is recommended to prevent mumps-associated hearing loss., Objective: The objective of this study is to investigate the clinical characteristics of hearing loss due to mumps and to evaluate hearing outcomes., Subjects and Methods: The clinical parameters were analyzed under a retrospective multi-institutional study design in patients diagnosed with hearing loss due to mumps at the Otolaryngology departments of 19 hospitals between 1987 and 2016., Results: Sixty-seven patients with hearing loss due to mumps were enrolled. The study population consisted of 35 males and 32 females, ranging in age from 1 to 54, with a median age of 9.5 years. Sixty-three patients presented with unilateral, and 4 with bilateral hearing loss. Profound hearing loss was observed in 65 ears. Only one ear with severe hearing loss showed complete recovery. Four patients with bilateral hearing loss received cochlear implant surgery. Most of the patients with hearing loss due to mumps had no history of vaccination.

Objectives: To present the cardiovascular risk factors in idiopathic sudden sensorineural hearing loss (SSNHL) patients enrolled in a nationwide epidemiological survey of hearing disorders in Japan., Materials and Methods: We compiled the cardiovascular risk factors in 3073 idiopathic SSNHL subjects (1621 men and 1452 women) and compared their proportions with controls as part of the National Health and Nutrition Survey in Japan, 2014. The cardiovascular risk factors consisted of drinking and smoking habits, a history of five conditions related to cardiovascular disease and body mass index., Results: The proportion of current smokers was significantly higher among men aged 50-59, 60-69 and 70+ and among women aged 30-39, 40-49 and 60-69. The proportion of patients with a history of diabetes mellitus was significantly higher among men aged 50-59, 60-69 and 70+, but not in women. In addition, male and female SSNHL subjects aged 60-69 showed lower proportions of current drinking; and female SSNHL subjects aged 60-69 showed higher proportions of overweight (BMI ≥25 kg/m 2 )., Conclusions: The present cross-sectional study revealed showed significantly higher proportions of current smokers among both men and women as well as those with a history of diabetes mellitus among men across many age groups in patients with idiopathic SSNHL compared with the controls.

Objective: To investigate the positive rate for the Cochlin tomo-protein (CTP: an inner ear-specific protein) detection test among patients with inner ear-related clinical manifestations and evaluate the clinical characteristics of definite perilymphatic fistula (PLF)., Methods: We have performed an ELISA-based CTP detection test using middle ear lavage (MEL) samples from 497 cases of suspected PLF enrolled from 70 clinical centers nationwide between 2014 and 2015. In addition to the CTP-positive rate, audio-vestibular symptoms were compared between CTP-positive and -negative cases., Results: 8-50% of patients in category 1 (trauma, middle and inner ear disease cases), and about 20% of those in categories 2, 3 and 4 (external origin antecedent events, internal origin antecedent events, and without antecedent event, respectively) were positive for CTP. In category 1 cases, the earlier tested samples showed a higher CTP-positive rate, whereas no differences were observed in categories 2, 3 or 4. The characteristic clinical features in the earlier tested cases were nystagmus and fistula sign in CTP test-positive cases in category 1, and streaming water-like tinnitus in those in categories 2, 3 and 4., Conclusion: The present study clarified that CTP detection test-positive patients exist at considerable rates among patients with inner ear-related manifestations.

Objectives: Using a large-scale nationwide survey database, we investigated the epidemiological characteristics for idiopathic SSNHL in Japan., Methods: The subjects for this analysis were patients registered in a Japanese multicentre database between April 2014 and March 2016. A total of 3419 idiopathic SSNHL patients were registered in the database, and the clinical characteristics of the idiopathic SSNHL patients were obtained. Several factors associated with the severity of hearing impairment and prognosis were then investigated. Statistical analysis was performed to clarify the factors associated with the severity of hearing impairment and prognosis., Results: There were significant correlations between the severity of hearing loss and diabetes mellitus, kidney disease, past history of brain infarction, heart disease, age (under 16 years/elderly), and symptoms of vertigo/dizziness. We also analyzed the prognostic factors for idiopathic SSNHL, and found that the severity of hearing loss (Grade 3 or 4), heart disease, aged 65 years or over, time from onset to treatment (over 7 days), and symptoms of vertigo/dizziness were all significantly related to poor prognosis., Conclusion: The present large-scale clinical survey revealed current epidemiological trends for idiopathic sudden sensorineural hearing loss (SSNHL) and various factors associated with the severity of hearing impairment and prognosis.

Objective: To investigate the hearing prognosis of idiopathic sudden sensorineural hearing loss (SSNHL) treated with different initial therapies., Methods: Subjects consisted of patients diagnosed with idiopathic SSNHL within 7 days from onset and showing severe hearing loss (≥60 dB), who were registered in a Japanese multicenter database between April 2014 and March 2016. Subjects were divided into four groups according to initial therapy: (1) steroids, (2) steroids + Prostaglandins (PGs), (3) intratympanic steroids (ITS), and (4) no steroids. Hearing outcomes were compared among the groups., Results: In total, 1305 patients were enrolled. The final hearing level and hearing gain of patients treated with steroids + PGs were significantly higher than those of patients treated with steroids alone or no steroids. The ratio of good prognosis (complete recovery or marked improvement) in patients treated with steroids + PGs was higher than that in patients treated with steroids alone or no steroids. There was no difference in the prognosis of patients treated with steroids alone or no steroids., Conclusion: A large number of patients with idiopathic SSNHL were registered in a multicenter database. PG use in combination with steroid administration was associated with a good hearing prognosis in patients with severe hearing loss.

Objectives: The aim of this study was to investigate the differences between idiopathic sudden sensorineural hearing loss (SSNHL), and acute low-tone sensorineural hearing loss (ALHL) using the results of a nationwide survey database in Japan and to analyze the variables associated with their clinical features and the severity of hearing impairment, treatment, and prognosis., Methods: Participants were patients registered between April 2014 and March 2016 in a multicenter epidemiological survey database involving 30 university hospitals and medical centers across Japan. Statistical analysis was performed to clarify the factors associated with their clinical characteristics and the severity of hearing impairment, treatment, and prognosis., Results: Idiopathic SSNHL and ALHL differed significantly in terms of male-to-female ratio, age distribution, and time from onset to start of treatment. The treatment methods and hearing prognosis also differed markedly between the two diseases. A majority (92%) of idiopathic SSNHL patients were administered some type of corticosteroid, while half of the ALHL patients received corticosteroids and a diuretic agent., Conclusion: The results suggested that idiopathic SSNHL and ALHL belonged to different categories of inner ear disease.

Objectives: To evaluate the differences between acoustic trauma (AT) and other types of acute noise-induced hearing loss (ANIHL), we performed a literature search and case reviews., Methods: The literature search based on online databases was completed in September 2016. Articles on ANIHL and steroid treatment for human subjects were reviewed. The source sounds and treatment sequelae of our accumulated cases were also reviewed. Hearing loss caused by gun-shots and explosions was categorized into the AT group, while hearing loss caused by concerts and other noises was categorized into the ANIHL group., Results: Systemic steroid treatment did not appear to be effective, at least in the AT group, based on both the literature and our case reviews. However, effective recovery after treatment including steroids was observed in the ANIHL group. The difference in hearing recovery between the AT and ANIHL groups was statistically significant (p = .030), although differences in age, days from the onset to treatment and pretreatment hearing levels were not significant., Conclusions: Hearing recovery from AT is very poor, whereas, ANIHL is recoverable to some extent. Therefore, it is essential to differentiate between these two groups for accurate prediction of the hearing prognosis and evaluation of treatment effects.

Objectives: A nationwide epidemiological survey involving 23 hospitals in Japan was conducted and the predictive values of demographic data were examined statistically., Methods: A total of 642 patients from 23 hospitals, including 20 university hospitals, in Japan were enrolled in the study. Age ranged from 8 to 87 years, and all were diagnosed with acute low-tone sensorineural hearing loss (ALHL) between 1994 and 2016. Demographic data for the patients, such as symptoms, gender, mean age, and distribution of ALHL grading, were collected and analyzed in relation to prognosis using Student's t-test, χ 2 test and logistic regression., Results: Female gender (p < .013), younger age (p < .001), low-grade hearing loss (p < .001), and shorter interval between onset and initial visit (p < .004) were significantly predictive of a good prognosis. The prognosis for definite ALHL was significantly better than that for probable ALHL (p < .007)., Conclusions: The severity of initial hearing loss, interval between onset and initial visit and age were important prognostic indicators for ALHL, while female gender was an important prognostic indicator peculiar to ALHL.

Conclusion: Approximately 50% of patients with sPLF based on the clinical diagnosis criteria were definitively diagnosed with CTP-positive sPLF. These results suggest that early surgery within 7 days of the disease onset contributes to improvements in the therapeutic response of hearing loss., Objectives/hypothesis: Idiopathic spontaneous perilymph fistula (sPLF) cannot be diagnosed reliably. It is speculated that this condition occurs in patients with vertigo-accompanied acute sensorineural hearing loss that progresses rapidly in spite of steroid therapy. This study herein evaluated cochlin-tomoprotein (CTP) test results in patients with sPLF who underwent exploratory tympanotomy and considered surgical outcomes with true sPLF., Study Design: Retrospective study., Methods: Twenty-three patients diagnosed with sPLF based on the clinical diagnosis criteria who underwent exploratory tympanotomy were included., Results: CTP test results were positive in 11 cases. In CTP-positive cases, the mean hearing level was 66.5 dB pre-operatively and 42.3 dB post-operatively. The hearing level post-operatively completely recovered in four cases, markedly recovered in three cases, slightly recovered in one case and showed no response in three cases. Hearing level improvements were significantly better in CTP-positive patients who underwent surgery within 7 days of the disease onset than in those treated 8 or more days after the disease onset.

Conclusions: The changes in the cochlin isoforms in the perilymph may provide important insights to the understanding of cochlin function and the pathogenesis of related inner ear diseases., Objectives: Cochlin is involved in various pathologies of the inner ear. Altered levels of cochlin isoforms in developing inner ear tissue were reported previously. The purpose of this study was to elucidate the cochlin isoform expression in the perilymph of rats during postnatal development in relation to Coch gene mRNA expression., Methods: We studied the cochlin isoforms in the rat perilymph during postnatal development by Western blot analysis. Real-time PCR was also performed to elucidate the expression level of Coch mRNA in the developing inner ear of rats., Results: Western blot analysis showed that the expression of p63s in the perilymph was highest on the 12th day after birth (DAB12), the earliest age at which we could identify the perilymphatic space microscopically, and it decreased gradually as the cochlea developed. On the other hand, the expression of Cochlin-tomoprotein (CTP)was lowest on DAB12 and increased gradually up to DAB24. COCH mRNA was detected from DAB3 and gradually increased to DAB15, and then gradually decreased to DAB70.

Conclusions: The cochlin-tomoprotein (CTP) detection test can be used to make a definite, objective diagnosis of traumatic perilymphatic fistula (PLF), and therefore offers valuable information on patient selection for surgical treatment., Objectives: Penetrating middle ear injury can cause traumatic PLF, which is a surgically treatable otologic emergency. Recently, we have reported on CTP, a novel perilymph-specific protein. The purpose of this study was to determine if the CTP detection test is useful for the diagnosis of traumatic PLF., Methods: This was a prospective study of CTP detection in penetrating middle ear injury cases with tympanic membrane perforation and hearing loss., Results: A total of seven individuals were included in this study. CTP was detected in three of four cases with posterosuperior quadrant perforation of the tympanic membrane. In one of these three cases, even though the high resolution CT scan was not suggestive of PLF and the perilymph leakage could not be visualized intraoperatively, the CTP detection test was able to detect PLF. In two cases, the preoperative positive test results enabled us to make a diagnosis of PLF and a decision for surgical treatment. CTP was not detected in the cases with anterior or inferior tympanic membrane perforation.

Conclusion: Similarly to almost all delayed endolymphatic hydrops (DEH) cases with both precedent sudden deafness and mumps deafness, two-thirds of DEH cases with precedent deafness of unknown cause with onset in early childhood developed DEH symptoms within 40 years after the precedent deafness. In spite of the diagnosis of precedent deafness, viral labyrinthitis may build up the late endolymphatic hydrops in most DEH cases up to four decades., Objective: To clarify the characteristics of DEH in Japan., Methods: Clinical information on 198 DEH cases was collected by nationwide, multicenter surveys conducted by the Peripheral Vestibular Disorders Research Committee of Japan., Results: The incidence of the ipsilateral type of DEH was 47.5%, which was almost equal to that of the contralateral type. In both types of DEH, the most common diagnosis of precedent deafness was deafness of unknown cause with onset in early childhood: 43.9% in both types of DEH. Sudden deafness and mumps deafness were the subsequent diagnoses of precedent deafness. The distribution of time delay of the onset between precedent deafness of unknown cause with onset in early childhood and DEH was different from that between precedent sudden and mumps deafness and DEH.

Conclusions: We have cloned guinea pig Coch cDNA and the sequence information will be useful for future molecular study combined with physiological experiments. Proper Coch gene expression appears to be dependent on the unique extracellular micro-environment of the inner ear in vivo. These results provide insight into the Coch gene expression and its regulation., Objective: To characterize the guinea pig Coch gene, we performed molecular cloning and expression analysis in the inner ear and cultured fibrocytes of the spiral ligament., Methods: The Coch cDNA was isolated using RACE. Cochlin isofoms were studied by Western blot using three different types of mammalian inner ear. The cochlear fibrocytes were cultured and characterized by immunostaining. Coch gene expression in the fibrocytes was investigated and the influence of cytokine stimulation was evaluated., Results: The full-length 1991 bp Coch cDNA that encodes a 553 amino acid protein was isolated. The sequence had significant homology with other mammals, and the sizes of the Cochlin isoforms were identical. In the cultured fibrocytes, Coch mRNA was expressed in a very small amount and the isoform production was different, compared with the results in vivo. Cytokine stimulation did not alter the level of mRNA expression or isoform formation.

Conclusions: By testing 125 samples, we confirmed that Cochlin-tomoprotein (CTP) is present in the perilymph, not in cerebrospinal fluid (CSF). Perilymph and CSF exist in two distinct compartments, even in the case of a malformed inner ear with a bony defect in the lamina cribrosa, as described here. Cochleostomy might have suddenly decreased the perilymph pressure, allowing the influx of CSF into the inner ear resulting in profuse fluid leakage, first perilymph then CSF., Objectives: The first purpose of this study was to further confirm the specificity of the perilymph-specific protein CTP that we reported recently. Secondly, we assessed the nature of the fluid leakage from the cochleostomy using the CTP detection test., Methods: A standardized CTP detection test was performed on 65 perilymph and 60 CSF samples. Samples of profuse fluid leakage collected from cochleostomy during cochlear implantation surgery of one patient with branchio-oto-renal (BOR) syndrome were also tested by the CTP detection test., Results: CTP was detected in 60 of 65 perilymph samples but not in any of the CSF samples. The leaked fluid was shown to contain CTP, i.e. perilymph, at the outset, and then the CTP detection signals gradually disappeared as time elapsed.

Conclusion: The incidence of new cases of Meniere's disease (MD) in elderly patients aged 60 years or more was found to have increased over time after correction for age distribution in the overall population. Job- and care-related fatigue may be involved in the recent increase in elderly-onset cases because physical and mental fatigue can induce onset of the disease., Objectives: Changes over time in the epidemiologic characteristics of MD in Japan were analyzed., Materials and Methods: Between 1975 and 2006, four nationwide, multi-center surveys of MD were conducted by the Meniere's Disease Research Committee of Japan (1975-1976) and the Peripheral Vestibular Disorders Research Committee of Japan (1982-1984, 1990, and 2001-2006). Information was collected by the committee members on a total of 1368 de novo cases of definite MD, 520 reported in the first survey, 290 in the second survey, 148 in the third survey, and 410 in the fourth survey., Results: Clear changes were seen over time in the population-adjusted sex distribution of the disease and population-adjusted age at onset. The number of definite MD cases in females increased over time relative to the number of cases in males. The proportion of cases in which onset occurred at 60 years of age or more increased over time when the number of cases in each age group was adjusted for changes in age distribution of the population over time. From the time of the third survey, there was a slight increase in the proportion of cases with bilateral involvement.

This study was designed to establish an experimental cell-mediated autoimmune labyrinthitis model in C57BL/6 mice, which could exhibit high reproducibility and be adopted for precise immunological analysis. Inner ear antigen (IEA) was prepared from bovine membranous labyrinth. Following pretreatment with cyclophosphamide (CP) and primary sensitization with IEA/FCA, many inflammatory cells infiltrated transiently into the perilymphatic and endolymphatic regions of the cochlea, vestibule and the endolymphatic sac, but not into the kidney, lung, brain or liver. This reaction occurred from day 7 and peaked on day 12 in all animals, and then rapidly reduced. This reaction occurred in all experimental mice during day 10 to day 12. The control mice showed no cellular reaction in the inner ear. These results suggest that the inner ear may possess cross-species organ-specific antigen and that a cell-mediated immune reaction may play an important role in the induction of autoimmune labyrinthitis.

Distribution of endothelin-1 (ET-1) in the cochlea of normal guinea pigs was determined by immunohistochemistry. ET-1 activity was identified with the mouse anti-human ET-1 IgG1 monoclonal antibody. ET-1 activity was distributed in the modiolus, spiral ligament, stria vascularis, spiral prominence. Reissner's membrane, supporting cells of the organ of Corti and spiral ganglion cells. These findings suggest that ET-1 may be involved in the regulation of fluid volume and ions of the cochlea.