Search

At present, there is no objective method for diagnosing subjective sensorineural tinnitus. Recently, the acoustic change complex (ACC) has been used to evaluate neural detection of sounds. Thus, the present study aimed to examine whether the ACC can reflect cortical detection and discrimination of sounds matched with tinnitus frequencies. We hypothesized that the ACC to change stimuli matched with tinnitus frequencies would be decreased in tinnitus patients because the tinnitus interferes with the perception of acoustic changes. To test the hypothesis, 96 ears of normal-hearing (NH) tinnitus patients and controls were tested. Among the tinnitus patients, 33 ears with a tinnitus frequency of 8 kHz constituted the tinnitus group, and the remaining 63 ears with no experience of tinnitus were allocated to the control group. For the 4 kHz non-tinnitus matched frequency, a subset of tinnitus (n = 17) and NH (n = 47) subjects was tested. The acoustic stimuli were pure tones with a total duration of 500 ms consisting of a 1 kHz tone in the first 250 ms and a second tone of either 8 kHz or 4 kHz in the latter 250 ms. The normalized amplitude of the ACC (naACC) was calculated separately for the amplitude of the N1’-P2’ complex evoked by an 8 kHz or 4 kHz change stimulus and for the amplitude of the N1-P2 complex elicited by the initial 1 kHz background stimulus. Our results showed that the naACC to an 8 kHz stimulus in the tinnitus group was significantly smaller than those to 4 kHz and 8 kHz in normal controls. Additionally, in the tinnitus group, the naACC to 4 kHz was greater compared to 8 kHz. The receiver operating characteristic (ROC) curve analysis conducted for naACC to 8 kHz at UCL revealed a fair degree of diagnostic efficacy. Overall, our results indicated that the ACC to a change stimulus matched with the tinnitus frequency can provide an objective measure of frequency-specific tinnitus. [ABSTRACT FROM AUTHOR]

Although recent advances in magnetic resonance imaging (MRI) techniques have contributed to the detection of tiny lesions in the internal auditory canal (IAC) that may be responsible for sudden sensorineural hearing loss (SSNHL), there have been relatively few studies on the clinical characteristics of intra-labyrinthine hemorrhage (ILH) and labyrinthitis versus those regarding IAC tumors. Our purpose was to investigate the frequency of those IAC lesions on MRI and their clinical characteristics. Initial MRIs of 200 patients with SSNHL (93 men, 107 women; mean age = 48.61 years, range: 18–84 years), as well as detailed clinical histories, audiological examinations, and thyroid function, lipid battery, and serological tests (for viral agents and autoimmune disease), were performed. All patients were hospitalized at the time of diagnosis of SSNHL and were administered the same treatment protocol. Patients were divided into idiopathic and secondary groups according to their MRI results. After discharge, they underwent follow-up audiometry and clinical examination at predetermined intervals (2 weeks, 1, 2, 4, and 6 months, and 1 and 2 years). Propensity score-matching and receiver operating characteristics curves of the initial parameters were used for estimating clinical characteristics. Of the 200 patients, 25 (12.55%) who had abnormal findings suggesting inner ear lesions on MRI were assigned to the secondary SSNHL group; within this group, 10 patients (10/200, 5%) had a tumor invading the IAC, 7 (7/200, 3.5%) had ILH, 6 (6/200, 3%) had labyrinthitis, and 2 (1%) had a structural deformity of the IAC. The secondary group showed significantly poor recovery of hearing function compared with that in the idiopathic group. Patients with ILH or labyrinthitis showed prognoses that were equally poor as those of patients with tumors in the secondary group. Additionally, patients with such lesions showed significant canal paresis on the lesion side at an early stage and a high prevalence of benign paroxysmal positional vertigo (BPPV). In conclusion, the prevalence of non-tumorous lesions on MRI represents common findings and showed a poorer treatment response than that of vestibular Schwannoma in patients with SSNHL. Abnormal canal paresis (cut-off value of 35% on the lesioned side, sensitivity 65.2% and specificity 67%), spontaneous nystagmus directed to the contralesional side, and positional vertigo would be the clinical presentation of SSNHL with IAC lesions, in which the presence of acute prolonged vertigo or positional vertigo compatible with BPPV suggests the possibility of a non-tumorous lesion, such as ILH or a labyrinthitis rather than an IAC tumor. [ABSTRACT FROM AUTHOR]

Background: Tinnitus is a common condition in adults; however, the pathophysiology of tinnitus remains unclear, and no large population-based study has assessed the associated risk factors. The aim of this study was to analyze the prevalence and associated risk factors of tinnitus. Methods: We conducted a cross-sectional study using data from the Korea National Health and Nutrition Examination Survey, with 19,290 participants ranging in age from 20 to 98 years old, between 2009 and 2012. We investigated the prevalence of tinnitus using a questionnaire and analyzed various possible factors associated with tinnitus using simple and multiple logistic regression analysis with complex sampling. Results: The prevalence of tinnitus was 20.7%, and the rates of tinnitus associated with no discomfort, moderate annoyance, and severe annoyance were 69.2%, 27.9%, and 3.0%, respectively. The prevalence of tinnitus and the rates of annoying tinnitus increased with age. The adjusted odds ratio (AOR) of tinnitus was higher for females, those with a smoking history, those reporting less sleep (≤ 6 h), those with more stress, those in smaller households, those with a history of hyperlipidemia osteoarthritis, rheumatoid arthritis, asthma, depression, thyroid disease, an abnormal tympanic membrane, unilateral hearing loss, bilateral hearing loss, noise exposure from earphones, noise exposure at the workplace, noise exposure outside the workplace, and brief noise exposure. Additionally, unemployed individuals and soldiers had higher AORs for tinnitus. The AOR of annoying tinnitus increased with age, stress, history of hyperlipidemia, unilateral hearing loss, and bilateral hearing loss. Conclusions: Tinnitus is very common in the general population and is associated with gender, smoking, stress, sleep, hearing loss, hyperlipidemia, osteoarthritis, rheumatoid arthritis, asthma, depression, and thyroid disease history. [ABSTRACT FROM AUTHOR]

Objectives: The objective of our study was to establish whether increased lipid profiles and obesity affect the prevalence and prognosis of sudden sensorineural hearing loss (SSNHL). Methods: This was a case-controlled study with a longitudinal design. According to our criteria, 324 patients with SSNHL were included in this study. To manage potential covariates, 972 subjects with normal hearing from the Korean National Health and Nutrition Examination Survey were matched as control group according to their propensity scores. Age, level of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and body mass index (BMI) were obtained from the clinical data. Multivariate logistic regression analysis was used to investigate the association between SSNHL and lipid profiles or obesity in the 1296 subjects. Multivariate Cox regression analysis was used to determine whether lipid profiles and obesity are prognostic factors in patients with SSNHL. Results: Mean body weight, BMI, TC, and TG were significantly higher in patients with SSNHL compared with control subjects (p<0.05). However, LDL-C values did not differ significantly between the two groups. Subjects with elevated TC and TG levels had a 2.20- (95% CI 1.50–3.24) and 1.50-fold (95% CI 1.08–2.08) increased odds, respectively, of SSNHL compared with subjects with normal TC and TG levels. Subjects with grade III BMI had a 1.59-fold (95% CI 1.17–2.16) increased odds of SSNHL. Multivariate Cox regression analyses revealed that BMI was an independent risk factor of treatment outcome, as patients with BMI ≥27.5 were less likely to achieve complete recovery than those with BMI <27.5 (p<0.05). Conclusions: The results of this study revealed that elevated TC and TG levels and increased BMI are significantly associated with the prevalence of SSNHL and its prognosis, indicating that vascular compromise may play an important role in the pathogenesis of SSNHL. [ABSTRACT FROM AUTHOR]