ОЦЕНКА СОСТОЯНИЯ СЛУХОВОГО АНАЛИЗАТОРА И АНАЛИЗ ФАКТОРОВ РИСКА У СТУДЕНТОВ

Soft tissue conduction is the third mode of auditory stimulation

Background Vestibular evoked myogenic potential (VEMP) test is an electrophysiological testing that can assess dysfunction of otolithic organs and the integrity of their pathways precisely. Aim Compare amplitude and latency of ocular and cervical vestibular evoked myogenic potentials evoked by air- and bone-conducted stimuli in three different groups. Materials and methods The control group (group 1) included ten healthy volunteers adults (20 ears) with normal hearing thresholds. Group 2 consisted of ten patients (20 ears) with conductive hearing loss (CHL) and group 3 comprised 10 patients (20 ears) with sensorineural hearing loss (SNHL). All participants underwent pure tone audiometry, immittancemetry ocular vestibular evoked myogenic potential (oVEMPs) and cervical vestibular evoked myogenic potential (cVEMPs) by air and bone conduction stimuli. Results The response rate of cVEMPs and oVEMPs elicited by both types of stimuli was 100% in control group and SNHL group. In the group of conductive hearing loss, air conduction(AC) (c VEMPs and o VEMPs) response rate was 60%. There was a statistically significant positive correlation between latencies of oVEMPs and cVEMPs evoked by AC and BC methods and degrees of hearing loss in SNHL group. Conclusion Ocular and cervical VEMPs elicited by bone conduction (BC) stimuli aren’t vulnerable to conductive hearing loss. Bc VEMPs provides assessment of vestibular system in patients with conductive hearing loss. Significant correlation was found between cVEMPs and oVEMPs abnormalities and severity of sensorineural hearing loss.

Extensive articulation tests with laboratory equipment on an individual with a marked, primarily-conductive impairment have shown that for such an impairment for equal levels above threshold: (1) An amplifier prescribed according to the “most comfortable equal loudness curve” is superior to one prescribed according to a “most comfortable” curve, which in turn is better than a uniform amplifier; (2) Bone conduction is more satisfactory than air conduction if a high pass filter with cut-off frequency of 350 cycles is used in conjunction with the bone receiver; (3) Air and bone conduction together are superior to either alone; (4) When air conduction is used, frequencies up to 350 cycles and above 6500 cycles may be cut off without appreciably affecting the articulation. (Similar tests on an individual with monaural high frequency impairment have shown that low frequencies up to 350 cycles can be eliminated for either ear without markedly affecting the articulation.) Further tests with wearable vacuum tube aids on the individual with conductive impairment, have shown (1) the superiority of a binaural aid over a monaural aid, and the equivalence in articulation of a monaural and a diotic aid; (2) approximate equivalence of bone and air conduction, with crystal units being used in each case.

ObjectivesTo characterize cervical vestibular evoked myogenic potentials (c-VEMPs) in bone conduction (BC) and air conduction (AC) in healthy children, to compare the responses to adults and to provide normative values according to age and sex.DesignObservational study in a large cohort of healthy children (n = 118) and adults (n = 41). The c-VEMPs were normalized with the individual EMG traces, the amplitude ratios were modeled with the Royston-Wright method.ResultsIn children, the amplitude ratios of AC and BC c-VEMP were correlated (r = 0.6, p < 0.001) and their medians were not significantly different (p = 0.05). The amplitude ratio was higher in men than in women for AC (p = 0.04) and BC (p = 0.03). Children had significantly higher amplitude ratios than adults for AC (p = 0.01) and BC (p < 0.001). Normative values for children are shown. Amplitude ratio is age-dependent for AC more than for BC. Confidence limits of interaural amplitude ratio asymmetries were less than 32%. Thresholds were not different between AC and BC (88 ± 5 and 86 ± 6 dB nHL, p = 0.99). Mean latencies for AC and BC were for P-wave 13.0 and 13.2 msec and for N-wave 19.3 and 19.4 msec.ConclusionThe present study provides age- and sex-specific normative data for c-VEMP for children (6 months to 15 years of age) for AC and BC stimulation. Up to the age of 15 years, c-VEMP responses can be obtained equally well with both stimulation modes. Thus, BC represents a valid alternative for vestibular otolith testing, especially in case of air conduction disorders.

Current research on sound source externalization primarily focuses on air conduction (AC). As bone conduction (BC) technology advances and BC headphones become more common, the perception of externalization for BC-generated virtual sound sources has emerged as an area of significant interest. However, there remains a shortage of relevant research in this domain. The current study investigates the impact of reverberant sound components on the perception of externalization for BC virtual sound sources, both with the ear open (BC-open) and with the ear canals occluded (BC-blocked). To modify the reverberant components of the Binaural Room Impulse Responses (BRIRs), the BRIRs were either truncated or had their reverberation energy scaled. The experimental findings suggest that the perception of externalization does not significantly differ across the three stimulation modalities: AC, BC-open, and BC-blocked. Across both AC and BC transmission modes, the perception of externalization for virtual sound sources was primarily influenced by the reverberation present in the contralateral ear. The results were consistent between the BC-open and BC-blocked conditions, indicating that air radiated sounds from the BC transducer did not impact the results. Regression analyses indicated that under AC stimulation, sound source externalization ratings exhibited strong linear relationships with the Direct-to-Reverberant Energy Ratio (DRR), Frequency-to-Frequency Variability (FFV), and Interaural Coherence (IC). The results suggests that BC transducers provide a similar degree of sound source externalization as AC headphones.

Comparison of umbo velocity in air- and bone-conduction

BackgroundChronic suppurative otitis media (CSOM) is a common otolaryngology disease, and cholesteatoma is the most aggressive type of CSOM. CSOM with and without cholesteatoma both result in a certain level of sensorineural damage, which can be categorized as air conduction (AC), bone conduction (BC), or air-bone gap (ABG), and AC, BC, and ABG are affected by many factors. Further analyses and comparisons of factors affecting sensorineural damage in CSOM with and without cholesteatoma were conducted in this study.MethodsA comparative study was conducted of 79 patients with CSOM (39 with cholesteatoma and 40 without cholesteatoma) whose diagnoses were mainly based on chronic middle ear infections and hearing loss (HL), typical computed tomography (CT) and surgical findings. Audiological evaluation included AC, BC and ABG, and sensorineural damage was defined as mixed and sensorineural HL (SNHL).ResultsIn relation to the types of HL, there were no significant differences between both groups. The CSOM with cholesteatoma group had significantly greater AC (P=0.000) and a significantly greater ABG (P>0.05) than the CSOM without cholesteatoma group, but BC did not differ significantly between both groups (P>0.05). The average AC-middle frequency (MF), AC-high frequency (HF), ABG-MF and ABG-HF of CSOM without cholesteatoma were smaller than these of CSOM with cholesteatoma (P<0.05). The degree of HL differed significantly between both groups (P=0.000). The CSOM with cholesteatoma group showed a higher level of HL than the CSOM without cholesteatoma group. The presence of cholesteatoma was presented a protective factor associated with sensorineural damage (P<0.05), while higher degrees of hearing and aging were risk factors (P<0.05), respectively.ConclusionsOur direct comparisons showed that HL progressed more rapidly in the CSOM with cholesteatoma group, which had higher frequencies in relation to AC, the ABG, and severity. However, in relation to BC, there were no significant differences between both groups, which was in line with the similar proportions of the types of HL in both groups. The logistic regression showed that the presence of cholesteatoma was a protective factor, and the degree of hearing and aging were risk factors associated with sensorineural damage.

To improve understanding of normal responses in infants by comparing air conduction (AC) and bone conduction (BC) auditory thresholds using both the auditory steady state response (ASSR) and behavioral testing methods in normal-hearing infants (6 to 18 months of age) and adults. At present, there are no correction factors available for estimating BC behavioral thresholds from BC ASSR thresholds, which is a barrier to clinical implementation of the ASSR. In addition, previous studies have reported infant-adult differences in AC and BC sensitivity, which suggest a "maturational" air-bone gap (ABG) that is not attributable to a conductive pathology; no study has yet compared AC and BC thresholds for either ASSR or behavioral methods in the same individuals. The objectives of the present study are: (1) to compare BC thresholds between methods and provide the initial step toward positing correction factors to predict BC behavioral thresholds, (2) to directly compare AC and BC thresholds to provide an accurate estimate of the maturational ABG, (3) to determine preliminary normal levels for BC and AC ASSRs to exponentially amplitude modulated stimuli, and (4) to investigate infant-adult differences in AC and BC thresholds using ASSRs and behavioral assessment tools. Participants were 23 infants (6.5 to 19.0 months of age) and 12 adults (17 to 50 years of age) with normal hearing. Thresholds were estimated at 500, 1000, 2000, and 4000 Hz using air- and bone-conducted stimuli for ASSRs and behavioral testing. The ASSR stimuli were exponential envelope modulated (amplitude modulation [AM]) at modulation frequencies of 78, 85, 93, and 101 Hz for 500, 1000, 2000, and 4000 Hz, respectively, presented simultaneously. Frequency-modulated (warble tone) stimuli were used for behavioral testing for both infants and adults, respectively. All stimuli were calibrated in dB HL. Thresholds were compared across frequency and between stimulus presentation modes, between age groups and assessment method. Normal levels for AC and BC ASSRs to AM stimuli were also calculated. The findings indicated that BC thresholds were, on average, 7 to 16 dB poorer for ASSR compared with visual reinforcement audiometry (VRA), but varied widely across infants. For infants, mean ABGs of 14 to 17 dB were found for low-frequency ASSR thresholds but mean ABGs for VRA thresholds were less than 10 dB. The preliminary normal levels for ASSR AM stimuli at 500, 1000, 2000, and 4000 Hz, respectively, were: (i) AC: 30, 30, 20, and 20 dB HL, and (ii) BC: 20, 20, 30, and 30 dB HL. There was a tendency for infant and adult ASSR thresholds to differ for BC, but not for AC. Behavioral thresholds for AC and BC were similar between infants and adults and across frequency. Infant-adult and AC-BC threshold differences are greater for ASSRs compared with behavioral measures. The results support the presence of a clinically significant maturational ABG in the low frequencies for infant ASSRs but not for VRA. The findings also show a significant offset between BC ASSR and BC VRA thresholds and large intersubject variability.

Using the Callsign Acquisition Test (CAT) to compare the speech intelligibility of air versus bone conduction

OBJETIVO: analisar e correlacionar os achados dos Potenciais Evocados Auditivos de Tronco Encefáico por Frequência Específica e da avaliação comportamental, por Via aérea e Via óssea, em crianças com perda auditiva sensorioneural ou mista. MÉTODO: a casuística foi composta por dez crianças com até três anos de idade, diagnosticadas com perda auditiva sensorioneural. Foram realizados os PEATE-FE nas frequências de 0.5, 1, 2 e 4 kHz e a audiometria comportamental nas mesmas frequências, tanto por via aérea como por via óssea. Os resultados dos dois procedimentos foram correlacionados afim de verificar se o PEATE-FE é capaz de predizer o status auditivo de crianças com deficiência auditiva. RESULTADOS: os resultados mostraram forte correlação entre os dois procedimento nas quatro frequências estudadas por via aérea; já na via óssea, foi encontrada forte correlação nas frequências de 0.5, 1 e 2 kHz e moderada em 4 kHz. CONCLUSÃO: os PEATE-FE estimaram a audição com forte precisão quando comparados à audiometria comportamental. Desta forma, a aplicação dos PEATE-FE possibilita a estimativa da audição até que possam ser determinados, com segurança, os limiares comportamentais na população estudada.

Auditory steady-state responses to bone conduction stimuli in children with hearing loss

The ambient noise level and noise-induced hearing impairment (NIHI) in 200 motorbike riders from six motorbike parks were evaluated. All were males aged between 20- 62 years. Subjects were sampled using a cluster sampling technique. Parameters measured were environmental noise using the noise meter (peters) and hearing function using an audiometer(amplaid). A control group of 150 males was selected from amongst the staff of the University of Benin Teaching Hospital and students of University of Benin after informed consent was obtained. The mean ambient noise for motor bike riders was 90 +10 dB a level significantly(x=0.000), higher than the International Standard Organization (ISO) standard of 60dB. That for control group was 50 + 10dB. While there was no NIHI in control group, a significant hearing impairment for both air conduction (AC) and Bone conduction (BC) was observed in the study group. Unlike previous observations AC and BC impairment were predominantly in the left ear. Development of both AC and BC impairments increased with period of exposure. Environment noise impacts adversely on hearing and is a risk factor in commercial motorbike riders. Development of NIHI is significantly higher in the left ear than right unlikein other occupations.

FigureThere is a different type of hearing device called the Baha® bone conduction implant, also known as an osseointegrated auditory prosthesis, that is made especially for people with a long history of sick ears and ear surgeries. Such patients tend to be frustrated with their poor hearing and are often nervous about the risk of another ear infection. They also want to avoid more ear surgery at all costs. If the health of the ear can be stabilized, which is often a challenge, a conventional hearing aid may be used. Unfortunately, ear infections tend to recur, making regular hearing aids contraindicated for long periods of time. Years ago we fitted people who had this problem with a bone conductor on a headband attached to a high-power, body-worn hearing aid. Some of these fittings brought much happiness to patients who after not hearing sound for many years suddenly could hear well. The down side of this type of fitting is the wear and tear that the vibrator and the headband inflict on the wearer's head. The band is often too loose or too tight. It is hard to keep in place, and it is uncomfortable to wear. Extended use of the vibrator leads to an indentation in the patient's head created by the constant pressure exerted by the bone vibrator, which eventually erodes the bone directly under the vibrator. We usually try to fix this problem by moving the vibrator to the opposite side of the head, but eventually patients move it back to the original spot because it allows them to hear better. Developed in Sweden in 1977, Baha received FDA clearance for use in this country in 1996. Cochlear purchased Entific, the company that made it, in 2005. HOW IT WORKS Implanting the Baha is a relatively simple surgical procedure. A prosthesis is screwed into the mastoid. Then, 3 to 6 months later, the Baha sound processor is attached to the prosthesis with a coupler. For people who have good hearing via bone conduction and poor hearing via air conduction, this can work extremely well. The amplified sound bypasses the defective outer and middle ear and goes directly into both inner ears. The quality of hearing is described as quite good. Currently, Baha implantation is restricted to people age 5 years and above. Before that age, a child may use a Baha sound processor worn on a soft band and used similarly to a conventional bone-conduction hearing aid. After surgery, the child may use the same Baha sound processor on the implant and abutment. The reason for restricting implantation by age is that younger children are thought to have immature bone density, which may not permit good osseointegration. To ensure osseointegration with pediatric patients, it is recommended that the sound processor not be attached to the prosthesis until 6 months after surgery. In adults the waiting period is usually 3 months. Figure 1 shows the parts of the Baha. The separate piece in the photo is the small titanium implant that is screwed into the bone behind the patient's ear. New bone tissue grows around the implant securing it to the head. The implant is attached to an abutment that connects it to the hearing aid. The main part of the system is the sound processor, which receives the sound, amplifies it, and then transfers it to the patient via vibrations.Figure 1: The Baha system.ADVANTAGES For appropriate candidates, Baha has several benefits over alternative fittings: Feedback is reduced or eliminated. There is no discomfort from wearing a large, tightly fitting earmold. The conductive hearing loss is bypassed so the power requirement is lower. Reducing the required gain results in less saturation and distortion. There is no headband to wear. Because Baha is perceived as a surgical procedure rather than a hearing aid, it is currently approved by Medicare and many insurance companies. ACCESSORIES Various accessories can be used with Baha. Direct audio input is available so the patient can connect to a stereo, TV, or MP3 player. The unit can be used with a Microlink FM receiver to help with classroom situations and hearing in noise. A telecoil unit can be used to improve telephone listening. SUMMARY If conventional hearing aids or ear surgery does not provide a patient with good hearing, then a Baha should be considered. Its use is indicated when feedback is intractable and/or when the patient suffers from irritated ears or has malformed ears or ear canals. The Baha is also sometimes recommended for single-sided deafness.

Awoman in her 40swas referred for an 8-day history of left facial nerve paralysis, left-ear hearing loss, and vertigo. Three days after her paralysis started, she noticed left ear painwith clear discharge. She had no prior episodes of hearing loss or imbalance, and there was no significant medical history. Findingsfromthepatient’sphysicalexaminationwerenotablefor acomplete left facialparalysis (House-Brackmanngrade6/6)anderythematous skin in the left external auditory canal and conchal bowl withmultiple lesionsthathadcrustedover (Figure,A[unaffectedear] andB [affectedear]).Her tympanicmembranewas intact, and there was no middle ear effusion. Audiometric evaluation revealed mild asymmetric left sensorineural hearing loss with a word recognition score of 92% for the left ear and 100% for the right ear. Because of thisasymmetry,magnetic resonance imaging(MRI)of the internalauditorycanalswithgadoliniumcontrastwasperformed.AnaxialpostgadoliniumT1-weighted sequencewith fat suppression revealedenhancement of the left facial nerve within the internal auditory canal andfallopiancanal (Figure,C).The left cochlearandvestibularnerves were also enhancing, as well as the left basal turn of the cochlea. What is your diagnosis? A

Surgical Considerations for an Osseointegrated Steady State Implant (OSIA2®) in Children.