Bone mineral density of the incus body and long process in patients with chronic otitis media and its relationship with functional outcome in type II tympanoplasty.

BACKGROUND: Inflammatory conditions such as chronic otitis media (COM) can cause irreversible impairments in the microarchitecture and functions of the incus, which subsequently leads to conductive hearing loss. OBJECTIVES: To investigate bone mineral density (BMD) of the incus body (IB) and long process (ILP) on preoperative temporal CT in COM patients with and without incudo-stapedial joint discontinuity (ISJD), and also to determine the association between BMD values and the postoperative air-bone gap (ABG) in the ISJD group. MATERIAL AND METHODS: The mean IB density (IBD)/occipital bone density (OBD) and ILP density (ILPD)/OBD values were compared between the patients with and without ISJD. The correlation between ABG gain and preoperative incus density values was assessed in the ISJD group. RESULTS: The mean IBD/OBD and ILPD/OBD values were significantly higher in patients with intact ISJ. There was a moderate positive correlation between postoperative ABG gain and ILPD/OBD values in the ISJD group. CONCLUSION AND SIGNIFICANCE: The decrease in BMD of the incus may involve ILP as well as IB in patients with ISJD caused by ILP lysis in COM. A higher preoperative ILPD/OBD was correlated with a higher postoperative ABG gain in COM patients with ISJD.

Binaural hearing in monaural conductive or mixed hearing loss fitted with unilateral Bonebridge.

Objective: To determine the benefits of binaural hearing rehabilitation in patients with monaural conductive or mixed hearing loss treated with a unilateral bone conduction implant (BCI). Methods: This monocentric study includes 7 patients with monaural conductive or mixed hearing loss who underwent surgical implantation of a unilateral BCI (Bonebridge, Med-El). An ITA Matrix test was performed by each patient included in the study - without and with the BCI and in three different settings - to determine the summation effect, squelch effect and head shadow effect. Subjective hearing benefits were assessed using the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire. Results: The difference in signal to noise ratio of patients without and with BCI was 0.79 dB in the summation setting (p < 0.05), 4.62 dB in the head shadow setting (p < 0.05) and 1.53 dB (p = 0.063) in the squelch setting. The APHAB questionnaire revealed a subjective discomfort in the presence of unexpected sounds in patients using a unilateral BCI (aversiveness score) compared to the same environmental situations without BCI, with a mean discomfort score of 69.00% (SD ± 21.24%) with monaural BCI versus 25.67% (SD ± 16.70%) without BCI (difference: -43.33%, p < 0.05). In terms of global score, patients wearing a unilateral Bonebridge implant did not show any significant differences compared to those without hearing aid (difference: -4.00%, p = 0.310). Conclusions: Our study shows that the use of a unilateral BCI in patients affected by monaural conductive or mixed hearing loss can improve speech perception under noise conditions due to the summation effect and to the decrease of the head shadow effect. However, since monaural BCIs might lead to discomfort under noise conditions in some subjects, a pre-operative assessment of the possible individual benefit of a monaural BCI should be carried out in patients affected by unilateral conductive or mixed hearing loss in order to investigate the possible additional effect of the fitting of hearing aids.

A Large-Scale Study of the Relationship Between Degree and Type of Hearing Loss and Recognition of Speech in Quiet and Noise.

OBJECTIVES: Understanding speech in noise (SIN) is the dominant complaint of individuals with hearing loss. For decades, the default test of speech perception in routine audiologic assessment has been monosyllabic word recognition in quiet (WRQ), which does not directly address patient concerns, leading some to advocate that measures of SIN should be integrated into routine practice. However, very little is known with regard to how SIN abilities are affected by different types of hearing loss. Here, we examine performance on clinical measures of WRQ and SIN in a large patient base consisting of a variety of hearing loss types, including conductive (CHL), mixed (MHL), and sensorineural (SNHL) losses. DESIGN: In a retrospective study, we examined data from 5593 patients (51% female) who underwent audiometric assessment at the Stanford Ear Institute. All individuals completed pure-tone audiometry, and speech perception testing of monaural WRQ, and monaural QuickSIN. Patient ages ranged from 18 to 104 years (average = 57). The average age in years for the different classifications of hearing loss was 51.1 (NH), 48.5 (CHL), 64.2 (MHL), and 68.5 (SNHL), respectively. Generalized linear mixed-effect models and quartile regression were used to determine the relationship between hearing loss type and severity for the different speech-recognition outcome measures. RESULTS: Patients with CHL had similar performance to patients with normal hearing on both WRQ and QuickSIN, regardless of the hearing loss severity. In patients with MHL or SNHL, WRQ scores remained largely excellent with increasing hearing loss until the loss was moderately severe or worse. In contrast, QuickSIN signal to noise ratio (SNR) losses showed an orderly systematic decrease as the degree of hearing loss became more severe. This effect scaled with the data, with threshold-QuickSIN relationships absent for CHL, and becoming increasingly stronger for MHL and strongest in patients with SNHL. However, the variability in these data suggests that only 57% of the variance in WRQ scores, and 50% of the variance in QuickSIN SNR losses, could be accounted for by the audiometric thresholds. Patients who would not be differentiated by WRQ scores are shown to be potentially differentiable by SIN scores. CONCLUSIONS: In this data set, conductive hearing loss had little effect on WRQ scores or QuickSIN SNR losses. However, for patients with MHL or SNHL, speech perception abilities decreased as the severity of the hearing loss increased. In these data, QuickSIN SNR losses showed deficits in performance with degrees of hearing loss that yielded largely excellent WRQ scores. However, the considerable variability in the data suggests that even after classifying patients according to their type of hearing loss, hearing thresholds only account for a portion of the variance in speech perception abilities, particularly in noise. These results are consistent with the idea that variables such as cochlear health and aging add explanatory power over audibility alone.

Hearing Loss and Tinnitus.

A focused history, otoscopic and tuning fork examination and formal hearing testing are the diagnostic pillars for the workup of hearing loss and tinnitus. The causes of hearing loss and tinnitus are varied and range from relatively common age-related hearing loss to rare tumors of the brain and skull base. In this chapter, the authors explain the diagnostic workup of hearing loss and tinnitus, review the pathophysiology of the most common causes, and describe the treatments available.

Study of complex structural variations of X-linked deafness-2 based on single-molecule sequencing.

X-linked deafness-2 (DFNX2) is cochlear incomplete partition type III (IP-III), one of inner ear malformations characterized by an abnormally wide opening in the bone separating the basal turn of the cochlea from the internal auditory canal, fixation of the stapes and cerebrospinal fluid (CSF) gusher upon stapedectomy or cochleostomy. The causative gene of DFNX2 was POU3F4. To investigate the genetic causes of DFNX2 and compare the efficiency of different sequencing methods, 12 unrelated patients were enrolled in the present study. Targeted next-generation sequencing (NGS) and long-read sequencing were used to analyze the genetic etiology of DFNX2. Six variants of POU3F4 were identified in this cohort by NGS. Three patients with a negative diagnosis based on NGS were enrolled in further long-read sequencing. Two of them were all found to carry structural variations (SVs) on chromosome X, consisting of an 870-kb deletion (DEL) at upstream of POU3F4 and an 8-Mb inversion (INV). The 870-kb DEL may have been due to non-homologous end joining (NHEJ), while non-allelic homologous recombination (NAHR) within a single chromatid may have accounted for the 8-Mb INV. Common POU3F4 mutations in DFNX2 included point mutations, small insertions and deletions (INDELs), and exon mutations, which can be detected by Sanger sequencing and NGS. Single-molecule long-read sequencing constitutes an additional and valuable method for accurate detection of pathogenic SVs in IP-III patients with negative NGS results.

Dural Contact to the Malleus Head in Patients with Superior Semicircular Canal Dehiscence (SSCD): Case Series and Review of SSCD and Tegmen Defects.

OBJECTIVE: Report a series of cases in which patients have concomitant superior semicircular canal dehiscence (SSCD) and a dehiscent tegmen tympani with Dural contact to the malleus head (DCMH). METHODS: An analysis of radiologic and audiologic data in 4 patients who presented with SSCD and DCMH at a tertiary care institution. A pertinent literature review was performed. RESULTS: Four patients (5 ears) had SSCD and DCMH. In 3 patients with unilateral DCMH, the mean maximum air-bone gap was 15 dB in the ear with DCMH compared to 50 dB in the ear without DCMH. Of the 5 ears with DCMH, the mean air conduction threshold at 250 Hz was 17 dB compared to 42 dB in the 3 ears without DCMH. CONCLUSIONS: We report the findings of DCMH in a series of 4 patients with bilateral SSCD. This limited series suggests that ears with SSCD and DCMH have less of an air-bone gap than would be expected, as 1 would expect an additive effect of DCMH and SSCD on the air-bone gap.

Adverse events associated with Bonebridge and Osia bone conduction implant devices.

PURPOSE: Active transcutaneous Bone Conduction Implants (BCIs) are relatively new to the market and may offer improved outcomes while reducing skin-related complications associated with previous models. The purpose of this study is to examine medical device reports (MDRs) submitted to the Food and Drug Administration's (FDA) Manufacturer and User Device Facility Experience (MAUDE) database to identify adverse events with the active, transcutaneous BCIs, Bonebridge and Osia. METHODS: A search of the FDA MAUDE database was conducted using product code "PFO" (for Active Implantable Bone Conduction Hearing System), brand names "Bonebridge" and "Osia." Data was collected on device malfunction, patient injury, inciting events, and subsequent interventions between July 1, 2018 and November 1, 2020. RESULTS: The search query yielded 83 reports that met inclusion criteria, 56 regarding Bonebridge and 27 regarding Osia. A total of 91 adverse events were reported, including 45 device malfunctions and 46 patient injuries. Of all adverse events reported for Bonebridge, 15 (26.3%, 15/57) documented patient injuries, while the majority (73.7%, 42/57) documented device malfunctions. Of all adverse events reported for Osia, 3 (8.8%, 3/34) were reported concerning malfunctions, while 31 (91.2%, 31/34) were reported for patient injuries. The most commonly reported adverse events included lack of conduction or hearing (n = 26, 28.6%), infection (n = 14, 15.4%), and intermittent or reduced conduction or hearing (n = 12, 13.2%). From the MAUDE database reported adverse events and the total number of Osia implants given to us from Cochlear over this 28 month period, we estimate patient injuries to occur in roughly 2.1% of patients. CONCLUSION: There are limitations to the database which make systemic analysis challenging. This study suggests that patients with transcutaneous, active BCIs may be experiencing fewer soft tissue injuries, but similar device malfunctions as those with previous models.

Conductive hearing loss during development does not appreciably alter the sharpness of cochlear tuning.

An increasing number of studies show that listeners often have difficulty hearing in situations with background noise, despite normal tuning curves in quiet. One potential source of this difficulty could be sensorineural changes in the auditory periphery (the ear). Signal in noise detection deficits also arise in animals raised with developmental conductive hearing loss (CHL), a manipulation that induces acoustic attenuation to model how sound deprivation changes the central auditory system. This model attributes perceptual deficits to central changes by assuming that CHL does not affect sensorineural elements in the periphery that could raise masked thresholds. However, because of efferent feedback, altering the auditory system could affect cochlear elements. Indeed, recent studies show that adult-onset CHL can cause cochlear synapse loss, potentially calling into question the assumption of an intact periphery in early-onset CHL. To resolve this issue, we tested the long-term peripheral effects of CHL via developmental bilateral malleus displacement. Using forward masking tuning curves, we compared peripheral tuning in animals raised with CHL vs age-matched controls. Using compound action potential measurements from the round window, we assessed inner hair cell synapse integrity. Results indicate that developmental CHL can cause minor synaptopathy. However, developmental CHL does not appreciably alter peripheral frequency tuning.

Decreasing auditory input induces neurogenesis impairment in the hippocampus.

Hearing loss is associated with cognitive decline and dementia risk. Sensorineural hearing loss suppresses hippocampal neurogenesis, resulting in cognitive decline. However, the underlying mechanism of impaired neurogenesis and the role of microglial activation and stress responses related to hearing loss in the hippocampus remains unknown. Using a conductive hearing loss (CHL) model, we investigated whether a decrease in sound level could induce impairment of hippocampal neurogenesis and examined the differences between unilateral CHL (uCHL) and bilateral CHL (bCHL). To establish the CHL mouse model, ears were unilaterally or bilaterally occluded for five weeks by auditory canal ligation. Although hearing thresholds were significantly increased following CHL, CHL mice exhibited no significant loss of spiral ganglion or hippocampal neurons. Hippocampal neurogenesis was significantly and equally decreased in both sides following uCHL. More severe decreases in hippocampal neurogenesis were observed in both sides in bCHL mice compared with that in uCHL mice. Furthermore, microglial invasion significantly increased following CHL. Serum cortisol levels, which indicate stress response, significantly increased following bCHL. Therefore, auditory deprivation could lead to increased microglial invasion and stress responses and might be a risk factor for hippocampal neurogenesis impairment.

Frequency-Specific Analysis of Hearing Outcomes Associated with Ossiculoplasty Versus Stapedotomy.

OBJECTIVE: Surgery on the ossicular chain may impact its underlying mechanical properties. This study aims to investigate comparative differences in frequency-specific hearing outcomes for ossiculoplasty versus stapedotomy. METHODS: A retrospective chart review was conducted on subjects who underwent ossiculoplasty with partial ossicular replacement prosthesis (PORP) or laser stapedotomy with self-crimping nitinol/fluoroplastic piston, and achieved closure of postoperative pure tone average air-bone gap (PTA-ABG) ≤ 15 dB. 45 PORP and 38 stapedotomy cases were included, with mean length of follow-up of 7.6 months. RESULTS: The mean change in PTA-ABG was similar for the 2 procedures (-17.9 dB vs -18.1 dB, P = .98). Postoperative ABG closure for stapedotomy was superior at 1000 Hz (8.9 dB vs 13.9 dB, P = .0003) and 4000 Hz (11.8 dB vs 18.0 dB, P = .0073). Both procedures also had improved postoperative bone conduction (BC) thresholds at nearly all frequencies, but there was no statistical difference in the change in BC at any particular frequency between the 2 procedures. CONCLUSION: Both procedures achieved a similar mean change in PTA-ABG. Stapedotomy was superior to PORP at ABG closure at 1000 Hz and at 4000 Hz, with 1000 Hz the most discrepant. The exact mechanism responsible for these changes is unclear, but the specific frequencies affected suggest that differences in each procedure's respective impact on the native resonant frequency and mass load of the system could be implicated.

Simultaneous bilateral stapes surgery after follow-up of 13 years.

BACKGROUND: Eighteen patients underwent simultaneous bilateral stapes surgery in 2003-2006. OBJECTIVES: We evaluated the long-term outcomes in this patient group, and assessed their hearing in noise and binaural hearing. MATERIAL AND METHODS: Fifteen patients returned questionnaires concerning their hearing, taste function, and balance. Thirteen patients underwent pure-tone and speech audiogram, Finnish matrix sentence test, video head impulse test, and clinical examination on average 13 years after surgery. RESULTS: We found no significant difference in air- and bone conduction pure-tone average, speech audiometry, and the air-bone gap between the 1-year and the late postoperative visits. One patient had bilaterally a partial loss of the vestibulo-ocular reflex of unknown cause. CONCLUSIONS AND SIGNIFICANCE: The hearing results 13 years after simultaneous bilateral stapes surgery remained good without any significant delayed complications. Simultaneous bilateral stapes surgery is a viable treatment option in selected patients with otosclerosis.

Active middle ear implant (vibrant soundbridge) in children with unilateral congenital aural atresia.

BACKGROUND: Detailed studies have not been conducted on sound localization and speech perception in noise in patients with unilateral congenital aural atresia (UCAA). AIMS/OBJECTIVES: To evaluate the benefits of the use of the Vibrant Soundbridge (VSB) for UCAA by performing audiometric and sound localization tests. MATERIALS AND METHODS: Four children with UCAA underwent VSB (VORP 503) implantation from 2018 to 2019. Speech perception tests in noise were conducted using the Japanese monosyllable test. The spatial configuration for speech testing consisted of speech presented from the front and noise presented into the normal ear (S0N90). The sound localization test was conducted using nine loudspeakers equally distributed in a semicircle. RESULTS: The children's speech perception in noise 6 months after VSB activation was significantly better than before activation (p < .05). Additionally, the children's sound localization ability after VSB activation was significantly better than before VSB activation. CONCLUSION AND SIGNIFICANCE: The benefits of VSB use in children with UCAA were revealed using audiometric and sound localization tests.

Hearing Rehabilitation Implementing a Transcutaneous Bone Conduction Device: Single-Center Experience.

Bone conduction implants based on percutaneous abutment acoustic transmission have been implemented in patients with satisfactory outcomes. However, adverse soft tissue outcomes present a limitation. Transcutaneous bone conduction devices (t-BCDs) are an alternative that may mitigate these complications. A retrospective review was performed of patients who underwent implantation of a t-BCD from 2013 to 2017. Surgical outcomes were reviewed including wound complications, frequency of device use, patient concerns regarding the device, and reported patient satisfaction. A total of 37 patients were implanted with the bone-anchored hearing aids, BAHA Attract (Cochlear™ Baha® Implant System). Average follow-up time was 271.8 days. Postoperatively, 7 (18.9%) patients complained of soft tissue changes or issues with wound healing. Twelve (32.4%) patients requested adjustment of their devices. The t-BCD is an excellent option for hearing rehabilitation. Overall, the complication rate is low, patient satisfaction is high, and successful conversion from a percutaneous device is possible with minimal risk.

Activity-Dependent Neurodegeneration and Neuroplasticity of Auditory Neurons Following Conductive Hearing Loss in Adult Mice.

We examined the functional and structural changes of auditory neurons (ANs) in adult mice after conductive hearing loss (CHL). Earplugs (EPs) were bilaterally inserted in male 8-week-old mice for 4 weeks [EP(+) group] and subsequently removed for 4 weeks [EP(+/-) group]. We examined the control mice [EP(-) group] with no EPs inserted at 12 weeks. The auditory brainstem response (ABR) was measured to determine the cochlear function before and after EP insertion, after EP removal, and at 4 weeks following EP removal. We examined the cochleae for hair cell (HC) and spiral ganglion neuron survival, synaptic and neural properties, and AN myelination. There was a significant elevation of the ABR threshold across all tested frequencies after EP insertion. After removing the occlusion, these threshold shifts were fully recovered. Compared with the EP(-) mice, the EP(+) mice showed a significant decrease in the ABR peak 1 amplitude and a significantly prolonged latency at all tested frequencies. There was no significant effect of auditory deprivation on the survival of HCs and ANs. Conversely, auditory deprivation caused significant damage to the synapses and myelin and a significant decrease in the AN size. Although functional changes in the ABR amplitude and latency did not fully recover in the EP(+/-) mice, almost all anatomical changes were fully recovered in the EP(+/-) mice; however, cochlear synapses only showed partial recovery. These results suggest that auditory activities are required to maintain peripheral auditory synapses and myelination in adults. The auditory deprivation model allows for assessment of the mechanisms of synaptopathy and demyelination in the auditory periphery, and synaptic and myelin regeneration in sensorineural hearing loss.

TORP ossiculoplasty in the presence of an intact stapes superstructure.

INTRODUCTION: In this series, we describe ossicular reconstruction using routine TORP in the presence of the stapes superstructure using a tympanic-membrane-to-footplate configuration. MATERIALS AND METHODS: This is a case series of 12 patients who underwent TORP ossiculoplasties from 1st January 2010 to 31st October 2017. Data collected included demographics, indication for surgery, status of the middle ear and pre-operative and post-operative audiometric data (including pure tone average (PTA) and air-bone gap (ABG)). RESULTS: The mean pre-operative PTA was 56.5 dB and ABG was 39.8 dB. Surgical success (ABG ≤ 20 dB) was achieved in 83.3%, with an average improvement in PTA of 24.3 dB and closure of ABG of 27.1 dB. The mean post-operative ABG was 12.7 dB. CONCLUSION: TORP ossiculoplasty with tympanic-membrane-to-footplate configuration is a feasible means of ossicular reconstruction, independent of the status or spatial arrangement of the remnant ossicles. Using this technique, it is possible to achieve a consistently good outcome for improvement in hearing and closure of ABG.

Early Osia® 2 bone conduction hearing implant experience: Nationwide controlled-market release data and single-center outcomes.

PURPOSE: Bone conduction hearing devices are a well-established treatment option for conductive or mixed hearing losses as well as single-sided deafness. The Osia® 2 System is an active osseointegrated device where a surgically implanted titanium fixture supports a newly developed piezoelectric actuator that is placed under the skin. METHODS: Nationwide data collected during a controlled-market release (CMR) of the Cochlear™ Osia® 2 System as well as outcomes at single, tertiary-level private practice Otology/Neurotology center were retrospectively reviewed. Key learnings from surgeons and audiologists are discussed. RESULTS: During the CMR period, 23 surgeons performed 44 operations on 43 recipients. The mean age of recipients was 44 years and mean surgery duration was 52 min. The most commonly used incision was postauricular but anterior to the device (78%). Five complications were observed during the CMR, none of which were device related. Twenty-one audiologists performed 33 Osia® 2 activations during the CMR. The mean age of this group was 47 years, and the mean duration of each activation appointment was 55 min. Single-center data at the authors' institution demonstrated an average additional PTA4 gain with the Osia® 2 patients of 9.6 dB compared to Baha Attract and 10.2 dB compared to Baha Connect. CONCLUSION: The Cochlear™ Osia® 2 System represents a significant advance in auditory osseointegrated implant technology. Digital piezoelectric stimulation delivers high power outputs, improves high frequency gain for optimal speech perception, and maintains safety while providing excellent patient satisfaction.

Fifteen-Year Follow-Up of Stapedotomy Patients: Audiological Outcomes and Associated Factors in a Middle Income Country.

OBJECTIVE: To evaluate the short-term (postoperative), medium-term (5 years), and long-term (10 and 15 years) audiometric results of patients who underwent stapedotomy and to determine specific factors associated with better postoperative outcomes. METHODS: This study is a retrospective case review of 486 ears with surgically confirmed stapes fixation who underwent microscopic small fenestra stapedotomy. Preoperative, postoperative, and medium- and long-term air conduction (AC), bone conduction (BC), and air-bone gap (ABG) were assessed. Postoperative factors associated with better postoperative outcomes were evaluated. RESULTS: At 10- and 15-year follow-ups, ABG, AC, and BC were significantly deteriorated but clinically preserved in comparison with postoperative results. According to a multiple quantile regression, younger age was associated with better postoperative results at 0.25 kHz (p = 0.003) and 4 kHz (p = 0.028) and a smaller preoperative ABG was associated with better audiometric results at 0.25 kHz (p = 0.048), 0.5 kHz (p = 0.001), and 4 kHz (p = 0.001). In addition, younger age (p = 0.001 for AC and p < 0.001 for BC) and preoperative AC PTA (p < 0.001 for AC) were significantly associated with better postoperative AC and BC PTA. CONCLUSIONS: Stapedotomy surgery provides short-, medium-, and long-term hearing benefits in our studied cohort. ABG, AC, and BC thresholds obtained after the surgery are clinically preserved in 5-, 10-, and 15-year follow-ups, with an age-expected BC deterioration. Smaller preoperative ABG and younger age were positive predictors for better postoperative ABG. Future research should address long-term subjective and quality of life outcomes.

Wideband absorbance pattern in adults with otosclerosis and ossicular chain discontinuity.

OBJECTIVES: Evidence from previous literature had shown that the use of a single frequency probe tone is not sensitive enough to detect middle ear pathologies, especially related to the ossicles, which hinders accurate diagnosis. The goal of the present study was to compare the outcome of wideband absorbance (WBA) tympanometry and to determine the difference in WBA pattern in adults with otosclerosis and ossicular chain discontinuity. MATERIALS AND METHODS: Estimated adult cases of otosclerosis (10 ears) and ossicular chain discontinuity (06 ears) along with healthy individuals (10 ears) in the age range of 24 to 48 years (mean age: 38.6 years) were considered for the study. WBA was measured at peak and ambient pressure along with resonance frequency and compared with the data obtained from the healthy individuals to determine the WBA pattern. RESULTS: Data analysis revealed a distinct WBA pattern showing high absorbance at 750 Hz for ossicular chain discontinuity compared to healthy individuals, whereas the otosclerosis group showed reduced absorbance (p < 0.05) at low frequencies (250 Hz to 1500 Hz). WBA measured at the peak and ambient pressure did not elicit any significant difference across the frequencies. Also, the average WBA tympanogram measured between 375 Hz and 2000 Hz showed a significant difference in ambient pressure only in the otosclerosis group. In comparison to healthy individuals (901 Hz), ossicular chain discontinuity showed a significant reduction in resonance frequency (674 Hz), whereas in cases with otosclerosis had higher resonance frequency (1445 Hz). CONCLUSIONS AND SIGNIFICANCE: The present study showed different WBA patterns between the groups and the absorbance values were significantly different at the low frequencies. This suggests that WBA has the potential to differentiate ossicles related pathologies from normal and also between the ear with otosclerosis and ossicular chain discontinuity.

Effects of Occlusion and Conductive Hearing Loss on Bone-Conducted cVEMP.

OBJECTIVE: To evaluate the effects of conductive hearing loss and occlusion on bone-conducted cervical vestibular evoked myogenic potentials (cVEMPs). STUDY DESIGN: Prospective cohort study conducted in the year 2018. The right ear of each volunteer was evaluated under 3 conditions by using bone-conducted cVEMPs: normal (open external auditory canal), occluded (conductive hearing loss with occlusion effect), and closed (conductive hearing loss without the occlusion effect). SETTING: Single academic center. SUBJECTS AND METHODS: The study comprised 30 healthy volunteers aged 20 to 35 years (16 women, 14 men). All had normal hearing and no vestibular or auditory pathologies. The thresholds and amplitudes of cVEMP responses were recorded for the 3 conditions. The results of each condition for a particular participant were compared. RESULTS: As compared with the open condition, the conductive condition increased thresholds by 2.8 dB (P = .01), and the occluded condition decreased thresholds by 3.8 dB (P = .008). The amplitude in the occluded condition was larger than the normal condition and the conductive condition (mean difference: 20.64 [P = .009] and 31.76 [P < .001], respectively). CONCLUSION: The occlusion effect is present in cVEMP responses. The mechanism is not due to the conductive hearing loss induced. Clinical implications include potentially altering vestibular function with sealed hearing aids and in the surgically modified ears (ie, obliterated ears and open cavity mastoidectomy).