Search Results (41)

Background: Recreational noise exposure from personal listening devices (PLDs) may lead to hidden hearing loss (HHL), affecting auditory nerve function despite normal pure-tone audiometry (PTA) and otoacoustic emissions (OAE). Subclinical auditory damage at the synaptic level often goes undetected by conventional assessments, emphasizing the need for more sensitive measures. Recorded click ABR in the presence of various levels of ipsilateral maskers for the better identification of auditory damage at the synaptic level. These results could help to develop a better objective diagnostic tool that can detect hidden hearing loss. Objective: To examine the effects of PLD usage on extended high-frequency audiometric thresholds and on click-evoked auditory brainstem responses (ABR) with and without ipsilateral masking in individuals with normal hearing. Materials and Methods: Thirty-five young adults aged 18–35 years (18 PLD users, 17 controls) with clinically normal hearing were recruited. Extended high-frequency audiometry (EHFA) was conducted from 9 to 16 kHz. Click-evoked ABRs were recorded at 80 dB nHL under unmasked and ipsilateral broadband noise-masked conditions at 50, 60, and 70 dB SPL. ABR analyses included absolute and relative amplitude (V/I) and latencies of waves I, III, and V. Results: PLD users demonstrated significantly elevated extended high-frequency thresholds compared to controls. ABR analyses revealed reduced Wave I amplitudes across stimulus conditions in PLD users, while Wave V amplitudes were largely preserved, resulting in consistently higher V/I amplitude ratios under masked conditions. No group differences were observed for Wave III amplitudes or absolute/interpeak latencies, except for a modest prolongation of I–III latency at one masker level in PLD users. Conclusions: Conventional audiological tests may not detect early auditory damage; however, extended high-frequency audiometry and ABR with ipsilateral masking demonstrate greater sensitivity in identifying noise-induced functional changes within the auditory brainstem pathways. Full article

Background/Objectives: Hearing loss is a prevalent sensory impairment in older adults, linked to reduced quality of life, cognitive decline, and social isolation. While it usually begins in the high-frequency range, some individuals present with isolated low-frequency hearing loss (LFHL). The long-term prognostic implications of such frequency-specific patterns remain unclear. This study aimed to evaluate the risk of long-term hearing deterioration by initial hearing loss type: LFHL, high-frequency hearing loss (HFHL), and combined-frequency hearing loss (CFHL). Methods: We retrospectively analyzed pure-tone audiometry (PTA) data from 10,261 patients who underwent at least two pure-tone audiometry assessments between 2011 and 2022 at a tertiary hospital. Each ear was treated as an independent observation. Hearing loss was defined as a threshold > 20 dB HL at 250, 500, 4000, or 8000 Hz. Participants were classified into normal hearing (NH), LFHL, HFHL, and CFHL groups. The outcome was a final four-frequency pure-tone average (4PTA) ≥ 40 dB HL. Logistic regression adjusted for age and sex was used, with subgroup analyses by follow-up duration. Results: HFHL (OR = 1.66, 95% CI: 1.47–1.89) and CFHL (OR = 2.23, 95% CI: 1.97–2.53) showed significantly higher risks of hearing loss compared with NH. LFHL did not show a significant increase (OR = 0.94, 95% CI: 0.76–1.16). These results were consistent across follow-up durations, with CFHL showing the most extensive deterioration. Conclusion: HFHL is a strong predictor of long-term auditory decline, and risk is further elevated with CFHL. In contrast, isolated LFHL was not associated with increased risk, suggesting relatively favorable outcomes. Frequency-specific classification may aid risk stratification and long-term monitoring strategies. Full article

Background: Despite the widespread use of antibiotics, acute mastoiditis (AM) and related complications resulting from acute purulent otitis media continue to occur, predominantly in children. Although numerous studies have focused on the pathogenesis, aetiological agents, and treatment of AM, comprehensive investigations of the long-term outcomes of AM and the physiological consequences of surgical intervention in the temporal bone are lacking. Methods: Thirty patients who had undergone mastoidectomy for acute mastoiditis at a median age of 2.12 years were invited for evaluation at least five years postoperatively. The assessment included the Chronic Otitis Media Questionnaire 12, clinical examination with otomicroscopy, extended high-frequency pure-tone audiometry, distortion product otoacoustic emissions, middle ear impedance testing, and a newly developed protocol for noninvasive mastoid function measurement. Results were compared with a control group of 30 ears and with a group of 30 ears treated solely with tympanostomy for acute otitis media at risk of mastoiditis. Results: Although mean Chronic Otitis Media Questionnaire 12 scores were below 1 point, patients who had undergone mastoidectomy reported slightly greater difficulties with hearing in both quiet and noisy environments, along with an increased perception of tinnitus and unpleasant sensations around the ear. Otomicroscopy revealed minor structural changes in the test groups, which were absent from the control group. Pure-tone audiometry demonstrated approximately 10 dB higher thresholds at high and extended high frequencies, with similar findings observed in the distortion product otoacoustic emissions. Middle ear impedance testing indicated elevated stapedius reflex thresholds in the mastoidectomy group, while other parameters showed no statistically significant differences. Mastoid function testing demonstrated preserved pressure-buffering capacity but reduced thermal insulation of the vestibular organ under extreme thermal stimulation—an occurrence rarely encountered in daily life. Conclusions: In the long term, most patients recovering from acute mastoiditis exhibit only minor functional and structural sequelae, and the impact of mastoidectomy appears negligible compared with less invasive surgical interventions. Full article

Background/Objectives: Cochlear “injury” is thought to be a significant cause of tinnitus in patients with hearing loss. Interestingly, individuals with normal hearing may also experience tinnitus. This study evaluates otoacoustic distortion product emissions (DPOAEs) in individuals with normal hearing who experience tinnitus perception. Methods: In this prospective study, the tinnitus group (TG) consisted of 34 subjects with tinnitus (four unilaterally) and normal hearing (threshold ≤ 25 dBHL at 0.25–8 kHz). The control group (CG) comprised 10 healthy volunteers (20 ears) without tinnitus and normal hearing. Medical history was recorded, and all participants underwent a complete otolaryngological examination, pure tone audiometry, and DPOAE recording (DP-gram, L1 = 55 dB, L2 = 65 dB, for F2: 619–10,000 Hz). Moreover, participants in the TG completed a detailed tinnitus history (with self-rated loudness scoring) and the Tinnitus Handicap Inventory (Greek-version THI-G) and underwent tinnitus analysis. Results: The recorded mean DPOAE values during the DP-gram of the CG were significantly larger in amplitude at low (t-test, Bonferroni-corrected p < 0.09) and high frequencies (t-test, Bonferroni-corrected p < 0.02) compared with the TG. Tinnitus assessment showed tinnitus pitch matching at the frequency area in the DP-gram, where the acceptance recording criteria were not met. There were no statistically significant differences in tinnitus onset, self-rated loudness scores of >70, and severe disability (THI-G > 58) for TG subjects in whom DPOAEs were not recorded at frequencies of ≤1000 Hz. Participants with abnormal DPOAEs at around 4000 Hz had tinnitus of sudden onset and severe disability (THI-G > 58). Finally, those with pathological recordings of DPOAEs at ≥6000 Hz had gradual onset tinnitus (Pearson Chi-square test, p < 0.05). Conclusions: DPOAEs in normal hearing individuals with tinnitus show lower amplitudes in low and high frequencies compared with normal hearing individuals without tinnitus. The tinnitus matched-frequency coincided with the frequency area where DPOAEs were abnormal. Full article

Background/Objectives: Tonal thresholds, typically assessed through pure-tone audiometry (PTA), are central to the audiological evaluation of Ménière’s disease (MD). However, they fail to capture the complexity of real-life speech perception. This study aimed to characterize the relationship between PTA and speech recognition performance in unilateral MD and to determine whether a measurable dissociation exists between hearing sensitivity and verbal processing. We also evaluated frequency-specific audiometric patterns and potential threshold cut-off values associated with speech recognition decline. Methods: A total of 254 ears from 127 patients were included in the study across three groups: the Ménière group (affected and unaffected ears, n = 64 each) and the control group (n = 63). The pure-tone thresholds, speech recognition threshold (SRT), and the maximum word recognition scores (Rmax) were assessed in all participants. Results: Although the Ménière affected and control groups showed comparable pure-tone average (PTA) values (46.33 vs. 38.13 dB, p = 0.439), the affected group demonstrated significantly poorer speech performance (Rmax: 76.25% vs. 87.49%, p < 0.001; SRT: 50.64 vs. 38.45 dB, p = 0.009). The Ménière unaffected group exhibited near-ceiling performance (Rmax: 99.38%, SRT: 18.33 dB) and a mean PTA of 19.59 dB. A strong correlation between PTA and SRT was observed only in the Ménière affected group (r = 0.942, p < 0.001), whereas correlations were moderate in the unaffected (r = 0.671, p < 0.001) and control (r = 0.728, p < 0.001) groups. The ROC analysis revealed that PTA predicted impaired speech recognition with high accuracy in unaffected (AUC = 0.956, p < 0.001) and control (AUC = 0.829, p < 0.001) ears but far less so in affected ears (AUC = 0.784; all p < 0.001), confirming a functional tonal–verbal dissociation in MD. Conclusions: This study demonstrates a functional audiometric dissociation in unilateral Ménière’s disease. Affected ears show poorer speech recognition and require higher intensities despite similar PTA values. The predictive link between thresholds and verbal performance is disrupted. These findings support the need for combined tonal and speech-based assessment in clinical practice. Full article

Background: Autism spectrum disorder (ASD) is a neurodevelopmental condition with a complex and multifactorial etiology, diagnosed on the basis of clinical criteria. Medical comorbidities are common and often lead to instrumental examinations; however, the clinical utility of routinely performing such tests remains uncertain. This study aimed to assess the practical value of instrumental assessments in ASD by examining both prescribing behaviors and the prevalence of abnormal findings in a sample of autistic children. Methods: A combined-method approach was adopted: (1) an online survey of child neuropsychiatrists across the Piedmont region (Italy) explored current attitudes and practices regarding instrumental testing in children with ASD; (2) a retrospective cross-sectional analysis examined the frequency and clinical relevance of abnormal findings in ASD patients who underwent comprehensive testing at a tertiary hospital in Turin. Results: The survey showed that 85.7% of centers follow specific protocols for instrumental examinations, though practices vary considerably. Genetic testing and blood analyses are routinely performed, while EEG, MRI, audiometry, and metabolic screenings are generally based on clinical indication. In the retrospective study, instrumental tests revealed a low rate of clinically significant findings. Clinically relevant genetic abnormalities were detected in 7.9% of CGH-array tests. EEG abnormalities were seen in 9% of cases, though 57% had nonspecific or unclear results. Among biochemical parameters, notable findings included altered lipid profiles (45%), ferritin deficiency (24%), and anemia (12.5%) and no metabolic disorders were identified. Discussion: These findings highlight substantial variability in clinical practice and suggest that while some instrumental tests may provide valuable insights, routine screening is often of limited benefit. The high prevalence of nonspecific findings reinforces the need for careful clinical correlation, emphasizing the importance of balancing comprehensive assessment against the risks of over-testing and challenges in interpreting results. Future research should focus on developing evidence-based guidelines for instrumental assessments in this population. Full article

Background: Occupational hearing loss (OHL) is a primary concern in industrial settings. In hospitals, the healthcare workers are also exposed to noise and chemical agents, the reported hearing loss in this occupation is underestimated. Hearing examination is routinely evaluated in the range of conventional frequencies, which may not detect hearing problems early. Therefore, this study aimed to reveal the hearing thresholds among medical personnel exposed to loud noise and/or chemical environments, estimating the prevalence of hearing loss using four different audiological methods. Methods: One hundred and thirty-one medical personnel were recruited from different units at the same hospital and grouped into noise, chemical, and mixed exposure categories. The hearing thresholds were assessed using four audiological methods, conventional audiometry (CA), extended high-frequency audiometry (EHFA), standard frequency distortion product otoacoustic emission (DPOAE), and ultra-high-frequency DPOAE. Statistical analyses were performed using R. Results: Ultra-high-frequency DPOAE and EHFA showed a higher prevalence of hearing loss than CA and DPOAE. Even CA usually demonstrated hearing threshold within normal limits, this study found a notch audiogram pattern indicating a decline in hearing loss over time at frequencies of 2, 3, and 4 kHz in each age group and a sign at a frequency of 6 kHz. Conclusions: Evidence of hearing loss can be identified with ultra-high-frequency DPOAE and EHFA, despite conventional audiometry indicating normal hearing thresholds. Full article

Pesticide exposure poses a significant health risk, with emerging evidence suggesting its impact on auditory function. This study investigated the effects of pesticide exposure on hearing in young rural residents living near agricultural areas in Chile’s O’Higgins Region. We evaluated 51 participants (31 exposed, 20 unexposed) aged 18–35 years, using comprehensive audiological assessments including high-frequency audiometry, distortion product otoacoustic emissions (DPOAEs), and auditory brainstem responses (ABR). Participants were classified based on residential proximity to agricultural areas, with exposed individuals living around 400 m or less from monoculture fields. Results revealed significant differences in high-frequency hearing thresholds (14 and 16 kHz) in exposed individuals. The exposed group showed a higher number of absent DPOAEs and reduced ABR wave V amplitude in the right ear compared to the unexposed group. Additionally, the wave V/I ratio was significantly lower in exposed individuals. These findings suggest that pesticide exposure, even without direct occupational contact, may induce measurable changes in auditory function, particularly affecting high-frequency hearing and neural responses. These results emphasize the need for enhanced monitoring and protective measures for populations residing near agricultural areas where pesticides are extensively used. Full article

Background/Objectives: In the early stage of presbycusis, patients experience reduced speech perception in noisy environments despite normal audiometry, normally known as hidden hearing loss. Diagnostic indicators like the reduced amplitude of ABR wave I, elevated extended high-frequency threshold (EHT), and decreased middle ear muscle reflex (MEMR) amplitude aim to identify biomarkers of peripheral auditory pathology but remain inconsistent. Mismatch negativity (MMN) is a cortical auditory evoked potential generated when the brain detects sound changes. This study aimed to assess MMN as a diagnostic tool for hidden hearing loss in adults. Methods: Seventy-three subjects with normal hearing underwent an extended pure-tone audiogram examination ranging from 0.125 to 16 kHz and a subsequent MMN assessment with two different paradigms: a speech (ba/da) and a tone (1/2 kHz) paradigm. The MMN’s amplitude and latency were measured and analyzed. Results: The outcome shows a significant age-related effect on MMN amplitude in the speech condition (χ² = 13.0, p = 0.002). Specifically, the MMN amplitude in the 25–30-year-old group was significantly smaller than in the 20–25-year-old group (p = 0.0015, Cohen’s d = 0.63). Additionally, no further effects of age were observed on the cortical potentials examined. Also, neither tone nor speech paradigms showed a significant influence of EHT on the amplitude or latency of either MMN or P300. Conclusions: The application of MMN as an electrophysiological tool to diagnose hidden hearing loss in normal hearing adults has limitations. However, in contrast to MMN responses to tonal stimuli, the present study reveals that MMN amplitude obtained with speech stimuli may indicate early signs of central auditory deficits. Full article

The misuse of personalized listening devices (PLDs) resulting in noise-induced hearing loss (NIHL) has become a public health concern, especially among youths, including medical students. The occupational use of PLDs that produce high-intensity sounds amplifies the danger of cochlear deterioration and high-frequency NIHL especially when used in noisy environments. This study aims to evaluate the incidence and trends of NIHL among medical students using PLDs. Background/Objectives: The purpose of this study is to assess the prevalence of high-frequency NIHL among PLD-using medical students. Methods: A semi-structured questionnaire covering details on PLD usage, exposure to noisy environments, and hearing difficulties was used to gather the data required. Conventional pure-tone audiometry with extended high-frequency audiometry was preceded by routine clinical evaluation using tuning fork tests and otoscopic examination for hearing loss assessment and to rule out middle-ear pathology. Hearing impairment was determined and categorized according to the Goodman and Clark classification system (250 Hz to 8000 kHz). SPSS version 21 was used in the analysis of the frequency data collected. Results: Out of 100 participants, using conventional PTA, 33% were found to have hearing loss, with 42.9% of males and 23.5% of females affected. Bilateral hearing loss was seen in 36.4% of the cases. Left-sided hearing loss was found to be more common (28%). The duration of usage of PLD had a significant correlation with hearing loss with a p-value < 0.0001. Hearing thresholds were significantly elevated at 16 kHz and 18 kHz in both the right and left ear. Conclusions: The high prevalence of PLD misuse among medical students is a major risk factor for NIHL. To help combat chronic hearing loss, students need to be educated about safe listening levels that can prevent further damage to the cochlea and auditory system. Full article

Background/Objectives: Conventional audiometry assesses hearing in the frequency range of 250–8000 Hz, while humans can detect sounds from 20 to 20,000 Hz. Hearing sensitivity above 8000 Hz can be assessed through “Extended high-frequency audiometry (EHFA)”, which is useful for early detection and monitoring of hearing loss and counseling for tinnitus patients. Despite its usefulness, age significantly affects hearing sensitivity. Currently, there are no standard hearing thresholds in the EHF range categorized by age groups in Thailand. In this study, the aim was to determine normative EHFA data across different age groups in a healthy Thai population. Methods: This study included 134 participants aged 18–70 years, categorized into five age groups. All participants had normal hearing thresholds and type A tympanograms bilaterally. Following this, EHFA measurement was performed. Results: Across all age groups, there was an observed increase in median hearing thresholds as age increased. In comparison, no significant difference in median hearing thresholds was found between individuals aged 18–30 and >30–40 years. However, those over 40 years had significantly higher median thresholds across all frequencies compared to those under 40 years (p < 0.05). Based on these findings, we propose two new subgroups of 18–40 years and >40–70 years. Median hearing thresholds for those aged 18–40 was ≤20 dB HL across most frequencies, except at 16,000 Hz (30 dB HL). In the >40–70 age group, thresholds ranged from 20 dB HL at 9000 Hz to 70 dB HL at 14,000 and 16,000 Hz. However, no significant differences were found in hearing thresholds between sexes and ear sides. Conclusions: In this study, normative EHFA data were established for healthy Thai adults, appropriately divided into two groups (18–40 and >40–70 years) for clinical use. Further studies with more participants per age group are also needed to validate the results. Full article

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. During and after COVID-19, audiovestibular symptoms and impairments have been reported. Objectives: This study aimed to investigate the impacts of COVID-19 on the peripheral and central auditory systems of children and adolescents following the acute COVID-19 phase based on behavioral, electroacoustic, and electrophysiological audiological assessments. Methods: This is a primary, prospective, observational, and cross-sectional study of 23 children aged 8 to 15 years who acquired confirmed COVID-19 and who, before infection, had not had any auditory complaints or school complications. The results were compared with pre-pandemic data collected from a similar group of 23 children who had normal peripheral and central hearing and good school performance. Each participant answered a questionnaire about child development, school, and health history and underwent tests including pure-tone audiometry and high-frequency audiometry, imitanciometry, transient evoked otoacoustic emissions, and distortion product otoacoustic emissions. They also received tests of Brainstem Auditory Evoked Potentials, Long Latency Auditory Evoked Potentials, Dichotic Digits Test, Sentence Identification Test, Dichotic Consonant–Vowel Test, Frequency Pattern Test, and Gaps-In-Noise Test. Results: Significant differences were observed between the groups, with the study group showing worse thresholds compared to the control group at both standard audiometric frequencies and at higher frequencies, although both groups were still within normal limits (p ≤ 0.05). In addition, the study group had a higher prevalence of absent responses, as identified by otoacoustic emissions and acoustic reflexes. In terms of central auditory performance, the study group showed ABRs with significantly longer latencies of waves I, III, and V compared to the control group. The study group also performed less well on the Dichotic Digits and Pediatric Speech Identification tests. Conclusions: COVID-19 appears to alter the auditory system, both peripherally at the level of the outer hair cells and more centrally. Full article

Background: It is assumed that speech comprehension deficits in background noise are caused by age-related or acquired hearing loss. Methods: We examined young, middle-aged, and older individuals with and without hearing threshold loss using pure-tone (PT) audiometry, short-pulsed distortion-product otoacoustic emissions (pDPOAEs), auditory brainstem responses (ABRs), auditory steady-state responses (ASSRs), speech comprehension (OLSA), and syllable discrimination in quiet and noise. Results: A noticeable decline of hearing sensitivity in extended high-frequency regions and its influence on low-frequency-induced ABRs was striking. When testing for differences in OLSA thresholds normalized for PT thresholds (PTTs), marked differences in speech comprehension ability exist not only in noise, but also in quiet, and they exist throughout the whole age range investigated. Listeners with poor speech comprehension in quiet exhibited a relatively lower pDPOAE and, thus, cochlear amplifier performance independent of PTT, smaller and delayed ABRs, and lower performance in vowel-phoneme discrimination below phase-locking limits (/o/-/u/). When OLSA was tested in noise, listeners with poor speech comprehension independent of PTT had larger pDPOAEs and, thus, cochlear amplifier performance, larger ASSR amplitudes, and higher uncomfortable loudness levels, all linked with lower performance of vowel-phoneme discrimination above the phase-locking limit (/i/-/y/). Conslusions: This study indicates that listening in noise in humans has a sizable disadvantage in envelope coding when basilar-membrane compression is compromised. Clearly, and in contrast to previous assumptions, both good and poor speech comprehension can exist independently of differences in PTTs and age, a phenomenon that urgently requires improved techniques to diagnose sound processing at stimulus onset in the clinical routine. Full article

Hearing impairment, a rare inherited condition, is notably prevalent in populations with high rates of consanguinity. The most common form observed globally is autosomal recessive non-syndromic hearing loss. Despite its prevalence, this genetic disorder is characterized by a substantial genetic diversity, making diagnosis and screening challenging. The emergence of advanced next-generation sequencing (NGS) technologies has significantly advanced the discovery of genes and variants linked to various conditions, such as hearing loss. In this study, our objective was to identify the specific variant causing hearing loss in a family from Syria using clinical exome sequencing. The proband in the family exhibited profound deafness as shown by pure-tone audiometry results. The analysis of the different variants obtained by NGS revealed the presence of a nonsense mutation within the CLDN14 gene. Through Sanger sequencing, we verified that this variant segregates with the disease and was not present in the control population. Moreover, we conducted a comprehensive review of all reported deafness-related CLDN14 mutations and their associated phenotypes. Furthermore, we endeavored to carry out a comparative analysis between the CLDN14 and GJB2 genes, with the objective of identifying potential factors that could explain the notable discrepancy in mutation frequency between these two genes. Full article

Inner ear involvement (IED) is a rare local complication of the very common acute otitis media (AOM). The most beneficial treatment for IED remains a matter of debate. The aim of this study is to analyze different treatment modalities based on hearing outcomes to contribute to the discussion of therapy for IED in AOM. This retrospective study includes 112 adult patients diagnosed with AOM with IED between 2000 and 2020. Patients either received conservative (systemic antibiotic and systemic steroid therapy), interventional (conservative plus myringotomy and tympanic tube) or operative (interventional plus antrotomy) treatment. Pre- and post-treatment pure tone audiometry was performed. The hearing outcome was compared, and hearing recovery was analyzed based on modified Siegel’s criteria. The pre-treatment pure tone average (PTA) was significantly (p < 0.05) higher in the operative group than in the other groups. All treatment modalities led to a significant hearing improvement (p < 0.001). The pre- and post-treatment hearing loss was predominantly observed in high frequencies 2–4 kHz. The operative group showed the highest rate of complete hearing recovery. While all treatment modalities led to a significant improvement in hearing, the operative group showed the most beneficial hearing results in patients with high pre-treatment hearing loss. It remains to be shown if the findings in patients with high pre-treatment hearing loss can be generalized to patients with mild or moderate pre-treatment hearing loss. Full article