Hearing loss in beta-thalassaemia: An Italian multicentre case-control study.

BACKGROUND: Despite numerous studies, the true scenario of hearing loss in beta-thalassaemia remains rather nebulous. MATERIALS AND METHODS: Pure tone audiometry, chelation therapy, demographics and laboratory data of 376 patients (mean age 38.5 ± 16.6 years, 204 females, 66 non-transfusion-dependent) and 139 healthy controls (mean age 37.6 ± 17.7 years, 81 females) were collected. RESULTS: Patient and control groups did not differ for age (p = 0.59) or sex (p = 0.44). Hypoacusis rate was higher in patients (26.6% vs. 7.2%; p < 0.00001), correlated with male sex (32.6% in males vs. 21.8% in females; p = 0.01) and it was sensorineural in 79/100. Hypoacusis rate correlated with increasing age (p = 0.0006) but not with phenotype (13/66 non-transfusion-dependent vs. 87/310 transfusion-dependent patients; p = 0.16). Sensorineural-notch prevalence rate did not differ between patients (11.4%) and controls (12.2%); it correlated with age (p = 0.01) but not with patients' sex or phenotype. Among adult patients without chelation therapy, the sensorineural hypoacusis rate was non-significantly lower compared to chelation-treated patients while it was significantly higher compared to controls (p = 0.003). CONCLUSIONS: Sensorineural hypoacusis rate is high in beta-thalassaemia (about 21%) and it increases with age and in males while disease severity or chelation treatment seems to be less relevant. The meaning of sensorineural-notch in beta-thalassaemia appears questionable.

Case Report: Leptospirosis Complicated by Persistent, Bilateral Sensorineural Hearing Loss.

The clinical manifestations of leptospirosis range from mild to life-threatening and can impact on multiple organ systems. A wide array of neurological manifestations of leptospirosis have been reported, although the pathophysiology of neuroleptospirosis remains incompletely understood. We present a case of leptospirosis complicated by bilateral sensorineural deafness, with nodular meningitis demonstrated in the internal auditory meatus on magnetic resonance imaging. The patient was treated with doxycycline, ceftriaxone, systemic and topical steroids, and hyperbaric oxygen therapy, with modest, but incomplete, improvement.

Sensorineural Hearing Loss due to Acute Carbon Monoxide Poisoning.

Carbon monoxide (CO) can cause "irreversible" severe-to-profound sensorineural hearing loss. However, there are few reports of detailed hearing test results. Here, we report a case of acute sensorineural hearing loss caused by acute CO poisoning with partial hearing recovery, evaluated by a detailed hearing examination. A 25-year-old woman was brought to the emergency department for attempted suicide. On admission, her consciousness was impaired, and she was treated for severe CO poisoning, including using hyperbaric-oxygen therapy. After regaining consciousness, symptoms of hearing loss and tinnitus were discovered, and a detailed audiological examination revealed bilateral hearing loss, suggesting cochlear damage. Steroids were systemically administered, and her hearing impairment was partially resolved. Sensorineural hearing loss caused by acute CO poisoning includes cochlear pathology and may be partially treatable. The early evaluation of hearing in patients with severe CO poisoning is advisable for early treatment.

A Case Report of Riboflavin Treatment and Cochlear Implants in a 4-Year-Old Girl with Progressive Hearing Loss and Delayed Speech Development: Brown-Vialetto-Van Laere Syndrome.

BACKGROUND Brown-Vialetto-Van Laere (BVVL) syndrome is a rare autosomal recessive disorder caused by mutations in intestinal riboflavin transporter genes, resulting in a motor neuron disorder of childhood, which can be associated with sensorineural deafness. This report describes a 4-year-old Polish girl with progressive hearing loss and delayed speech development diagnosed with Brown-Vialetto-Van Laere syndrome who was treated with riboflavin (vitamin B2) and cochlear implants. CASE REPORT The case report concerns a girl from Poland who, at the age of 2 years 10 months, developed progressive atypical neurological symptoms of unknown etiology: ataxia of the upper and lower limbs, gait abnormalities, generalized muscle weakness, visual and hearing problems, and regression of speech development. A karyotype study (whole-exome sequencing) revealed alterations within SLC52A2, leading to the diagnosis of Brown-Vialetto-Van Laere syndrome and initiation of high-dose riboflavin treatment. As a 4-year-old child, she presented to the Institute of Physiology and Pathology of Hearing - World Hearing Center in Poland with progressive hearing loss and speech regression. Hearing tests revealed bilateral profound sensorineural hearing loss with auditory neuropathy. Surgical treatment was applied in the form of bilateral cochlear implantation. CONCLUSIONS This report shows the importance of genetic testing in infants who present with atypical symptoms or signs. In this case, the diagnosis of Brown-Vialetto-Van Laere syndrome resulted in timely correction of the genetic riboflavin (vitamin B2) deficiency and improved hearing following the use of cochlear implants.

Steroid Efficacy on Audiologic Recovery in Patients With Sudden Sensorineural Hearing Loss and Vestibular Schwannoma: A Retrospective Review.

OBJECTIVES: The objectives of this study are to (i) estimate the incidence of vestibular schwannoma (VS) among patients in an integrated healthcare system who present for evaluation of sudden sensorineural hearing loss (SSNHL) and (ii) evaluate the efficacy of empiric steroid therapy on audiologic recovery among SSNHL patients ultimately diagnosed with VS. METHODS: A retrospective chart review was performed on patients presenting with SSNHL in 2021 at a multicenter integrated healthcare system serving over 4 million members. Patient demographics, audiometric data, VS diagnosis, therapeutic steroid intervention, and data regarding treatment response were recorded. A clinically significant audiometric improvement was defined as (i) an increase of 15% in word recognition score, (ii) a decrease of 15 dB in four-frequency pure-tone average (PTA) using frequencies of 500, 1000, 2000, and 4000 Hz, or (iii) a PTA of <20 dB on follow-up audiogram. RESULTS: Six hundred fifty-eight patients were reviewed, of which 309 (56.0% male; mean, 57.5 years) met the inclusion criteria with audiometric data and magnetic resonance imaging data. Ten patients (70.0% male; mean, 51.3 years) were found to have VS. Of these, five patients received oral steroid therapy alone, and five had combination therapy (oral + intratympanic steroid injections). No patients received intratympanic steroid therapy alone. Median PTA improvement with steroid therapy was 3.1-dB hearing loss, and median word recognition score improvement was 16.5%. Six of 10 patients demonstrated clinically significant audiometric improvement with steroid therapy. CONCLUSION: This study represents the largest US-based study showcasing the prevalence of VS in patients originally presenting with SSNHL. It also reinforces previous findings that VS does not preclude trials of steroid therapy.

Distorted Tonotopy Severely Degrades Neural Representations of Connected Speech in Noise following Acoustic Trauma.

Listeners with sensorineural hearing loss (SNHL) struggle to understand speech, especially in noise, despite audibility compensation. These real-world suprathreshold deficits are hypothesized to arise from degraded frequency tuning and reduced temporal-coding precision; however, peripheral neurophysiological studies testing these hypotheses have been largely limited to in-quiet artificial vowels. Here, we measured single auditory-nerve-fiber responses to a connected speech sentence in noise from anesthetized male chinchillas with normal hearing (NH) or noise-induced hearing loss (NIHL). Our results demonstrated that temporal precision was not degraded following acoustic trauma, and furthermore that sharpness of cochlear frequency tuning was not the major factor affecting impaired peripheral coding of connected speech in noise. Rather, the loss of cochlear tonotopy, a hallmark of NH, contributed the most to both consonant-coding and vowel-coding degradations. Because distorted tonotopy varies in degree across etiologies (e.g., noise exposure, age), these results have important implications for understanding and treating individual differences in speech perception for people suffering from SNHL.SIGNIFICANCE STATEMENT Difficulty understanding speech in noise is the primary complaint in audiology clinics and can leave people with sensorineural hearing loss (SNHL) suffering from communication difficulties that affect their professional, social, and family lives, as well as their mental health. We measured single-neuron responses from a preclinical SNHL animal model to characterize salient neural-coding deficits for naturally spoken speech in noise. We found the major mechanism affecting neural coding was not a commonly assumed factor, but rather a disruption of tonotopicity, the systematic mapping of acoustic frequency to cochlear place that is a hallmark of normal hearing. Because the degree of distorted tonotopy varies across hearing-loss etiologies, these results have important implications for precision audiology approaches to diagnosis and treatment of SNHL.

Using electrocochleography to detect sensory and neural damages in a gerbil model.

Hearing is one of the five sensory organs that allows us to interact with society and our environment. However, one in eight Americans suffers from sensorineural hearing loss that is great enough to adversely impact their daily life. There is an urgent need to identify what part/degree of the auditory pathway (sensory or neural) is compromised so that appropriate treatment/intervention can be implemented. Single- or two-tone evoked potentials, the electrocochleography (eCochG), were measured along the auditory pathway, i.e., at the round window and remotely at the vertex, with simultaneous recordings of ear canal distortion product otoacoustic emissions. Sensory (cochlear) and neural components in the (remote-) eCochG responses showed distinct level- and frequency-dependent features allowing to be differentiated from each other. Specifically, the distortion products in the (remote-)eCochGs can precisely localize the sensory damage showing that they are effective to determine the sensory or neural damage along the auditory pathway.

Auditory cortex hypoperfusion: a metabolic hallmark in Beta Thalassemia.

BACKGROUND: Sensorineural hearing loss in beta-thalassemia is common and it is generally associated with iron chelation therapy. However, data are scarce, especially on adult populations, and a possible involvement of the central auditory areas has not been investigated yet. We performed a multicenter cross-sectional audiological and single-center 3Tesla brain perfusion MRI study enrolling 77 transfusion-dependent/non transfusion-dependent adult patients and 56 healthy controls. Pure tone audiometry, demographics, clinical/laboratory and cognitive functioning data were recorded. RESULTS: Half of patients (52%) presented with high-frequency hearing deficit, with overt hypoacusia (Pure Tone Average (PTA) > 25 dB) in 35%, irrespective of iron chelation or clinical phenotype. Bilateral voxel clusters of significant relative hypoperfusion were found in the auditory cortex of beta-thalassemia patients, regardless of clinical phenotype. In controls and transfusion-dependent (but not in non-transfusion-dependent) patients, the relative auditory cortex perfusion values increased linearly with age (p < 0.04). Relative auditory cortex perfusion values showed a significant U-shaped correlation with PTA values among hearing loss patients, and a linear correlation with the full scale intelligence quotient (right side p = 0.01, left side p = 0.02) with its domain related to communication skills (right side p = 0.04, left side p = 0.07) in controls but not in beta-thalassemia patients. Audiometric test results did not correlate to cognitive test scores in any subgroup. CONCLUSIONS: In conclusion, primary auditory cortex perfusion changes are a metabolic hallmark of adult beta-thalassemia, thus suggesting complex remodeling of the hearing function, that occurs regardless of chelation therapy and before clinically manifest hearing loss. The cognitive impact of perfusion changes is intriguing but requires further investigations.

Effectiveness of electroacupuncture for the treatment of sudden sensorineural hearing loss: A retrospective study.

ABSTRACT: This retrospective study investigated the use of electroacupuncture (EA) for the treatment of patients with sudden sensorineural hearing loss (SSNHL).Between May 2016 and April 2020, 140 patients with SSNHL were retrospectively analyzed. They were allocated to a treatment group (n = 70, received EA) and a control group (n = 70, received acupuncture). They received EA or acupuncture for a total of 3 months. The outcomes included average hearing threshold (AHT), tinnitus (as assessed by tinnitus handicap inventory [THI]), dizziness (as measured by dizziness handicap inventory [DHI]), and adverse events (AEs).After treatment, patients in both groups exerted more reduction in HT (P < .01), THI (P < .01), and DHI (P < .01), than those before the treatment. Furthermore, patients in the treatment group showed more relief in HT (P < .01), THI (P < .01), and DHI (P < .01), than those of patients in the control group. When it comes to AEs, both modalities had similar safety profile.The findings of this retrospective study indicated that the effectiveness of EA is superior to acupuncture in treating SSNHL. Future high quality studies are needed to warrant the present findings.

Prevalence of Sensorineural Hearing Loss in Pediatric Patients with Sickle Cell Disease: A Meta-analysis.

OBJECTIVES: To determine the prevalence of Sensorineural Hearing Loss (SNHL) attributable to Sickle Cell Disease (SCD) in the global pediatric population and to identify factors contributing to its severity. STUDY DESIGN: Meta-analysis. METHODS: We performed a comprehensive literature search for scientific articles in PubMed, Scopus, CINAHL, Web of Science, and the Cochrane Library that reported the incidence of hearing loss in populations under 18 years of age with excluding studies analyzing patients on iron chelation therapy, adults, or those without objective audiological analysis. RESULTS: We identified 138 initial studies with 17 selected for analysis after applying the exclusion criteria. A total of 1,282 SCD patients and 553 controls were included in the meta-analysis. There was a statistically significant increase in the prevalence of SNHL in children with SCD compared to the general population with a cumulative risk ratio of 3.33. CONCLUSION: This is the first systematic investigation of the relationship between SCD and SNHL in pediatric patients across the globe. The increased prevalence of SNHL in the pediatric SCD population warrants future research into the predictors of SNHL severity and merits routine audiometric monitoring of SCD patients to reduce the social and developmental morbidity of hearing loss at a young age. PROSPERO Registration #: CRD42019132601. Laryngoscope, 131:1147-1156, 2021.

HBO2 for sudden sensorineural hearing loss.

Sudden sensorineural hearing loss (SSNHL) presents as an abrupt onset of hearing loss; 88% of these presentations are idiopathic (ISSHL). Many mechanisms of injury and etiopathologies have been postulated, but they share a common result - hypoxia of the organ of Corti leading to hair cell-cilia fusion, synaptic, dendritic swelling and sustained depolarization. Of all of the various treatments tried, only corticosteroids and hyperbaric oxygen (HBO2) therapy have shown benefit in randomized controlled trials (RCTs). This paper reviews the pathophysiology of SSNHL, the variety of treatments studied, and the best evidence (both retrospective case controlled and prospective randomized controlled studies) for the use of HBO2 and corticosteroids. The best results are obtained when these two treatments are combined and initiated within 14 days of symptom onset. HBO2 is given at 2-2.5 ATA for 90 minutes for 10-20 sessions. Steroids should be dosed at 1mg/kg/day and slowly tapered over two to three weeks. If a patient is not a good candidate for or refuses systemic steroids, good results have also been obtained using intratympanic (IT) steroids in combination with HBO2. Patients should be followed by and otolaryngologist before, during and following HBO2. For severe hearing loss treatment with HBO2 improves by 37.7 dB, 19.3dB for those with moderate loss and 15.6 dB improvement overall. These recoveries, on average, improve a patient's hearing from ranges requiring hearing aids and sign language, to levels at which normal or near-normal hearing is restored.

Response to the letter to the editor: "Score risk scale as a prognostic factor after sudden sensorineural hearing loss".

We appreciate the opportunity to comment the observations on our paper entitled "Score risk scale as a prognostic factor after sudden sensorineural hearing loss", by Capuano et al. This letter highlights several important points, including the role of hyperbaric oxygen therapy and the possible association between patent foramen ovale and sudden sensorineural hearing loss (SSHL). Further research is needed to strengthen the association between cardiovascular risk and SSHL. We thank the authors for their insights into our paper and for adding their experience and observations on the potential role of cardiovascular risk in the etiology of SSHL.

SCORE risk scale as a prognostic factor after sudden sensorineural hearing loss.

Menezes et al. recently published an interesting study on cardiovascular prognostic factors for sudden sensorineural hearing loss (SSNHL), analyzing therapeutic strategies with intravenous and intratympanic corticosteroids and evaluating the application of the Systematic Coronary Risk Evaluation risk scale to classify risk in patients with SSNHL. In addition to intravenous and intratympanic corticosteroids, we would like to stress the role of hyperbaric oxygen therapy (HBOT). The new guidelines on SSNHL and the most recent scientific evidence emphasize the therapeutic role of HBOT. In a previous study, we recommended the use of HBOT in addition to intravenous steroid for patients with idiopathic SSNHL. For the best outcomes, we also recommended starting treatment within 14 days from the onset of SSNHL. In the same article, we discussed potential risk factors for SSNHL. Among cardiovascular risk factors, we suggest the possible association between patent foramen ovale (PFO) and SSNHL. The higher prevalence of PFO in our patients (50%) compared to controls suggests that SSNHL may be attributable to a paradoxical embolism, such as a venous embolism as a result of PFO.

HIRUDOTHERAPY IN PRESBYACUZIS PRAECOX IN CLEAN-UP WORKERS AFTER THE CHORNOBYL ACCIDENT DURING THE POST-CATASTROPHE YEARS. / GIRUDOTERAPIIa PRY PRESBYACUZIS PRAECOX V UChASNYKIV LIKVIDATsIÏ NASLIDKIV AVARIÏ NA ChORNOBYL'S'KIY̆ ATOMNIY̆ ELEKTROSTANTsIÏ U PISLIaAVARIY̆NYKh ROKAKh.

OBJECTIVE: to study the hirudotherapy efficacy in presbyacuzis praecox in clean-up workers (CUWs) of the Chornobyl disaster (ChD) during the post-accident years. MATERIALS AND METHODS: From archive data of previously examined 8,136 males' CUWs we selected among them 129 persons with the determined presbyacuzis praecox during the post-accident years. According to the physical dosime- try data the individual radiation of received by CUWs during the work on a rotational scheme in the Chornobyl exclu- sion zone from the end of 1986 to 1992-1994 amounted to 0.21-0.50 Gy. The examinations were carried out using a modern standard set of audiometric, vestibulometric and electrophysiological methods. Two forms of sensory and neural hearing loss in the elderly were distinguished, namely the presbyacuzis and presbyacuzis praecox. Prior to work in the exclusion zone, patients' auditory and vestibular functions were within normal range. Among 129 patients, 68 ones with presbyacuzis praecox were included in two main age groups (aged 40-49 and 50-59 yrs) and were treated using hirudotherapy, taking into consideration their coagulation hemostasis. Other 61 patients of analogical age groups were treated by allopathotherapy. For the analysis of results obtained, techniques of variational statistics were used. RESULTS: Direct correlation (r = 0.71) between inhibitory processes in central areas of the auditory analyzer in pres- byacuzis praecox in CUWs was established by electrophysiology and by speech audiometry data obtained before the treatment. Hyperacusis signs were detected in CUWs of two main and two control groups. Following the use of two treatment schemas, a significant improving of auditory functions was found (p < 0.05) according to tone and speech audiometries. The positive hirudotherapy effect concerning hearing functions was registered in 88% cases (in 59 CUWs among 68 ones); if allopathotherapy had been used, such effect was found in 65% cases (in 45 control patients among 61 ones of control group). The duration of allopathotherapy effect reached 6-9 months comparing to 12-18 months of hiruditherapy one, being twice longer. Improving the patients' coagulation hemostasis, hirudotherapy activated cardiovascular activity favoring the increase of social adequacy in CUWs with presbyacuzis praecox. CONCLUSIONS: It has been shown that hirudotherapy as a kind of naturopathy has significant advantages over alopa- totherapy by the absence of side effects, 23.0% higher and twice as long as improvement of auditory functions. Hirudotherapy, as an effective therapeutic and recreational measures, should be more widely implemented in clini- cal practice in order to minimize the development and progression of diseases in the special population of people who have been exposed to ionizing radiation due to the Chornobyl catastrophe to continue their vitality.

Risk of sudden sensorineural hearing loss in patients with dysrhythmia: A nationwide population-based cohort study.

OBJECTIVE: Whether dysrhythmia is a risk factor of sudden sensorineural hearing loss (SSNHL) remains unclear. In this study, we aimed to investigate the risk of developing SSNHL among patients with dysrhythmia in different age and gender groups by using population-based data in Taiwan. METHODS: We conducted a matched cohort study by analyzing data between January 2000 and December 2013 obtained from the Taiwan National Health Insurance Research Database. 41,842 newly diagnosed dysrhythmia patients and 83,684 comparison subjects without dysrhythmia were selected from claims. The incidence of sudden sensorineural hearing loss at the end of 2013 was determined in both groups. Univariate and multivariate logistic regression analyses were used to investigate the risk of SSNHL among patients with dysrhythmia. RESULTS: The incidence of SSNHL was 1.30-fold higher in the dysrhythmia group compared with the control group (53.2 versus 40.9 per 100,000 person-years), and using Cox proportional hazard regressions, the adjusted hazard ratio (HR) was 1.40 (95% confidence interval [CI], 1.15-1.70). Gender-stratified analysis revealed a significantly higher risk of SSNHL in patients with dysrhythmia than in those without dysrhythmia for both men and women (HR = 1.34, 95% CI = 1.02-1.76, P = 0.039, HR = 1.35, 95% CI = 1.02-1.78, P = 0.035, respectively). Age-stratified analysis revealed remarkable associations between dysrhythmia and SSNHL among those aged less than 40 years and more than 65 years (HR = 2.18, 95% CI = 1.03-4.64, P = 0.043 and HR = 1.54, 95% CI = 1.14-2.09, P = 0.006, respectively). CONCLUSIONS: Our findings support dysrhythmia as an independent risk factor for SSNHL. Based on the study results, clinicians managing patients with dysrhythmia should be aware of the increased risk of developing SSNHL, especially among patients aged <40 and >65 years, and counsel patients to seek medical advice immediately if they experience any acute change in their hearing ability.

An unusual case of sudden sensorineural hearing loss after cycling class.

In this case report, our patient developed sudden sensorineural hearing loss (SSNHL) after loud noise exposure during a popular cardiovascular group exercise cycling class. To increase awareness among all healthcare professionals of the effects of these modern-day group fitness classes on hearing loss, we describe this case and review the current literature on SSNHL and its management. A 35-year old man developed SSNHL in the setting of loud noise exposure during a high intensity aerobic exercise class. After a short course of oral steroids with no improvement, intratympanic steroids were administered weekly for three weeks. The patient showed minimal improvement; thus, hyperbaric oxygen therapy was conducted. Serial audiograms continued to show severe to profound mixed hearing loss in the right ear. In conclusion, individuals who participate in loud, high-intensity aerobic group-exercise classes should be careful of the potential for noise-induced hearing loss. Aerobic exercise may make these individuals more susceptible to noise-induced hearing loss. Early intervention is critical for any chance of recovery.

Different prognoses in patients with profound sudden sensorineural hearing loss.

Background: Inner ear hemorrhage is increasingly recognized as a cochlear lesion that can cause profound sudden sensorineural hearing loss (SSNHL). Objectives: To investigate changes of cochlear and vestibular function and to compare therapeutic recovery from profound SSNHL induced by different etiologies. Material and methods: Eighty patients with profound SSNHL (≥90 dB) were divided into an inner ear hemorrhage group and a non-inner ear hemorrhage group by MRI. Statistical analysis was performed to compare the therapeutic effects from vertigo and hearing loss and the outcomes of follow-up in the two groups. Results: There were significant differences between the two groups in terms of the overall 14-day therapeutic response rate (20 vs. 48%), the incidence of imbalance (26.7 vs. 6%), the incidence of semicircular canal dysfunction on the affected side (60 vs. 20%), the incidence of abnormal C-VEMP and O-VEMP on the affected side (63.3 vs. 38%; and 60 vs. 30%, respectively), the average hearing threshold (74.2 ± 10.7 vs. 53.6 ± 11.4 dB), and the word recognition score (65.5 ± 21.7 vs. 83.5 ± 24.5%) at a 12-month follow-up. Conclusions and significance: A higher percentage of patients with profound SSNHL induced by inner ear hemorrhage were associated with vertigo and had a poor prognosis.

Cochlear implantation under local anesthesia: a possible alternative for elderly patients.

INTRODUCTION: As average life-expectancy increases, a sufficient hearing rehabilitation for elderly patients with severe-to-profound sensorineural hearing loss becomes more important. Cochlear implantation is a relatively safe surgical procedure also for elderly patients, the higher risk is caused by general anesthesia. We report on four patients who underwent cochlear implantation under local anesthesia. METHODS: After detailed preoperative examinations (audiological tests, imaging, genetic tests, evaluation of motivation and compliance of the patient), four patient with severe-to-profound hearing loss were selected for cochlear implantation under local anesthesia. For the electrode insertion, we used the posterior suprameatal approach technique. Pre- and postoperative pure tone audiometry and speech-perception tests were conducted to prove the success of the procedure. RESULTS: The mentioned technique was applied; the average length of the operation was 52 min. The intraoperative measurements showed normal impedance and normal neuronal response telemetry, all the patients had sound experience during the intraoperative examination of the engineer. No complications were observed. The postoperative audiological tests showed a significant increase in the hearing perception. CONCLUSION: Cochlear implantation under local anesthesia is a safe and fast procedure for elderly patients. The intraoperative sound experience can give an extra motivation in the postoperative rehabilitation. Our results prove that by carefully selected elderly patients cochlear implantation can assure a significant increase in speech perception. We can establish that the new posterior suprameatal approach technique combined with local anesthesia presents a viable future option for those patients who were inoperable beforehand because of high risks of general anesthesia.

High frequency transient-evoked otoacoustic emission measurements using chirp and click stimuli.

Transient-evoked otoacoustic emissions (TEOAEs) at high frequencies are a non-invasive physiological test of basilar membrane mechanics at the basal end, and have clinical potential to detect risk of hearing loss related to outer-hair-cell dysfunction. Using stimuli with constant incident pressure across frequency, TEOAEs were measured in experiment 1 at low frequencies (0.7-8 kHz) and high frequencies (7.1-14.7 kHz) in adults with normal hearing up to 8 kHz and varying hearing levels from 9 to 16 kHz. In combination with click stimuli, chirp stimuli were used with slow, medium and fast sweep rates for which the local frequency increased or decreased with time. Chirp TEOAEs were transformed into equivalent click TEOAEs by inverse filtering out chirp stimulus phase, and analyzed similarly to click TEOAEs. To improve detection above 8 kHz, TEOAEs were measured in experiment 2 with higher-level stimuli and longer averaging times. These changes increased the TEOAE signal-to-noise ratio (SNR) by 10 dB. Slower sweep rates were investigated but the elicited TEOAEs were detected in fewer ears compared to faster rates. Data were acquired in adults and children (age 11-17 y), including children with cystic fibrosis (CF) treated with ototoxic antibiotics. Test-retest measurements revealed satisfactory repeatability of high-frequency TEOAE SNR (median of 1.3 dB) and coherence synchrony measure, despite small test-retest differences related to changes in forward and reverse transmission in the ear canal. The results suggest the potential use of such tests to screen for sensorineural hearing loss, including ototoxic loss. Experiment 2 was a feasibility study to explore TEOAE test parameters that might be used in a full-scale study to screen CF patients for risk of ototoxic hearing loss.