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Objectives: The recurrence rate of sudden sensorineural hearing loss (SSNHL) varies from 0.8% to 40%. However, to the best of our knowledge, no data on long-term hearing variations are present in the literature. The aim of this observational study was to analyze long-term variations of the hearing threshold in unilateral SSNHL without recurrence., Materials and Methods: A total of 50 patients affected by unilateral SSNHL were evaluated. Patients underwent a treatment consisting of intravenous corticosteroids. Clinical and audiometric features were recorded. Patients underwent pure tone audiometry at a mean follow-up of 5.26±2.28 years. Differences between the affected and unaffected ear were analyzed., Results: Comparing the post-treatment and follow-up audiograms, there was a worsening of hearing in the unaffected ear. On the contrary, no significant difference over time was found for the affected ear. 54% of patients showed no changes over time, 26% showed worsening, and 20% showed an improvement in hearing. The variation correlated with alcohol consumption and the presence of vasculopathies. An average improvement of hearing over time was observed at low frequencies., Conclusion: The time evolution in SSNHL is not predictable on the basis of the clinical and audiometric data. The majority the patients shows no changes in hearing loss in the affected ear. Patients who consume alcohol or have vasculopathies also have a higher risk of worsening of hearing. Further prospective studies are mandatory to better assess variations over time and their relationship with the effect of aging on hearing.

Hearing loss in Menière's disease has been described to affect above all low frequencies (upward curve) with a tendency to become irreversible and non-fluctuating at the higher frequencies (peaked curve) over time. The aim of the study was to determine the effects of MD on hearing function on the basis of differences existing between the affected and the unaffected ear in a group of patients affected by definite unilateral MD and whose contralateral ear was not affected by any disease other than age-related hearing loss (ARHL). Following this procedure we have also evaluated the possible effects of age and disease duration on hearing loss in MD. The study group consisted of 86 subjects affected by definite unilateral MD. In our sample a peaked audiometric curve characterized the affected ears; however, the result after subtracting the normal ear hearing threshold was an upward sloping curve, which highlighted the greater suffering at the lower frequencies. On the basis of differences existing between affected and unaffected ear, our data suggest that threshold evolution is more related to disease duration rather than to age.

Objective: To assess the role of the efferent auditory system by inhibition of contralateral otoacoustic emission in dyslexic children with auditory processing disorders., Methods: The study sample was 34 children: 17 with dyslexia and 17 age-matched controls. Sensitive speech tests (low-pass filtered, time-compressed, distorted and dichotic) were performed to assess coexisting auditory processing disorder. Distortion-product otoacoustic emission (DPOAE) values were measured in basal condition and with contralateral broadband noise signal delivered via an earphone transducer at 60 dB SPL., Results: The lower scores at sensitive speech testing confirmed the association of an auditory processing disorder in the dyslexic children. DPOAE values were significantly attenuated by contralateral inhibition only in the control group (p=0.001; dyslexics, p=0.19); attenuation was not significant at any frequency in the dyslexic group., Conclusions: The differences in DPOAE attenuation between the groups, although not statistically significant, suggest alterations in the auditory efferent system in the dyslexic population. These alterations may affect language perception. If confirmed in further studies with larger samples, these results could provide insight into a possible pathophysiological background of dyslexia., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: To assess differences in hearing threshold estimation of four different ABR tone-bursts at 1kHz., Methods: Twenty-one (21) ears from 11 subjects were tested with pure-tone audiometry (PTA): 5 ears (24%) were normal hearing, 5 (24%) affected by mild hearing loss, 7 (33%) showed moderate hearing loss and 4 (19%) severe hearing loss. After PTA each subject underwent tone-burst ABR test at 1kHz using a linear gated (L&#95;ABR) or Blackman windowed (B&#95;ABR) stimuli with (nn&#95;ABR) and without ipsilateral notched noise. Stimulation rate and filters settings were unchanged., Results: Overall correlation between PTA and all ABRs thresholds was high, ranging from 0.84 to 0.94. In normal hearing ears none of the differences was significant, except for those measured with B&#95;nn&#95;ABR, which showed a mean 16dB overestimation of the pure-tone threshold (p<0.05). In mild hearing loss group none of the differences between thresholds were significant. In moderate and severe hearing loss groups significant differences were measured with L&#95;nn&#95;ABR (p<0.05) with a mean 7.5dB underestimation of PTA., Conclusions: Although very similar, some significant differences were found when considering specific group of patients with different degrees of hearing loss., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

To assess the reliability of Blackman windowed tone burst auditory brainstem response (ABR) as a predictor of hearing threshold at low frequencies. Fifty-six subjects were divided in to three groups (normal hearing, conductive hearing loss, sensorineural hearing loss) after pure tone audiometry (PTA) testing. Then they underwent tone burst ABR using Blackman windowed stimuli at 0.5 kHz and 1 kHz. Results were compared with PTA threshold. Mean threshold differences between PTA and ABR ranged between 11 dB at 0.5 kHz and 14 dB at 1 kHz. ABR threshold was worse than PTA in each but 2 cases. Mean discrepancy between the two thresholds was about 20 dB in normal hearing, reducing in presence of hearing loss, without any differences in conductive and sensorineural cases. Tone burst ABR is a good predictor of hearing threshold at low frequencies, in case of suspected hearing loss. Further studies are recommended to evaluate an ipsilateral masking such as notched noise to ensure greater frequency specificity.

The auditory steady-state responses to single continuous tones modulated in amplitude have been proposed as an alternative to objective frequency-specific audiometry. The aim of this study was to compare thresholds obtained by pure-tone audiometry (PTA) and by auditory steady-state responses in normal hearing or affected by hearing loss in adults and in order to evaluate the applicability of this objective test in no collaborative hearing-impaired subjects. Eleven people, 6 normal hearing and 5 with hearing loss, underwent PTA and multiple frequency auditory steady-state responses; simultaneous carrier tones (0.5, 1, 2 and 4 KHz) modulated in amplitude at different rates (77-105 Hz) were presented monaurally (TDH 49 earphones) at variable intensities (110-20 dB SPL). The mean threshold difference between PTA and multiple frequency auditory steady-state responses was 28 dB (standard deviation=14.2) and R correlation value at 0.5-1-2-4 kHz was 0.71 (P=0.0012) at the Pearson's test. These differences were significantly smaller considering the hearing-impaired separately (11.7 dB, standard deviation=2.9). The results of this study confirm previous reports showing that the multiple auditory steady-state response method is an accurate predictor of the behavioural audiogram in patients with sensory-neural hearing impairments and can be used as a valid support for behavioural evaluations.

Until now the relationship between auditory threshold and age has been evaluated in normal subjects only. In this study the Author reports results obtained in a cross-sectional study on 416 subjects suffering from noise-induced hearing loss who were exposed to noise for 10 years at least. The results show that hearing loss over time was more correlated to age than to noise exposure. Moreover, the evolution of hearing loss over time had a linear shape while in noise-induced hearing loss evolution has a logarithmic shape and in presbyacusis it has an exponential shape. The differential threshold between 30 and 60 years obtained by applying the linear regression model was, at higher frequencies, significantly reduced compared to normal subjects. These results suggest that threshold values related to age obtained in normal subjects can not be applied in subjects affected by noise-induced hearing loss.

The paper analyzes the 8 KHz threshold in subjects with noise-induced hearing loss. The study group consisted of 315 subjects occupationally exposed to noise and suffering from acoustic trauma, which was considered as a mean threshold of more than 25 dB at 2, 3 and 4 KHz. The mean shape of audiograms was characterized by a neurosensory deficit which was more elevated at 4 and 6 KHz whereas the threshold at 8 KHz was better. However, this pattern was found in 60% of the cases whereas in the remaining 40% the threshold at 8 KHz was worse. Subjects with the most impaired audiometric threshold at 8 KHz were mainly older, although cases were found in a low percentage of younger subjects. The results demonstrate that in individual cases it is impossible, on the basis of the shape of the audiogram, to establish whether a hearing loss is due to noise or age.