L Reisinger,G Demarchi,N Weisz
Publication date 28-11-2023
Tinnitus has been widely investigated in order to draw conclusions about the underlying causes and altered neural activity in various brain regions. Existing studies have based their work on different tinnitus frameworks, ranging from a more local perspective on the auditory cortex to the inclusion of broader networks and various approaches towards tinnitus perception and distress. Magnetoencephalography (MEG) provides a powerful tool for efficiently investigating tinnitus and aberrant neural activity both spatially and temporally. However, results are inconclusive, and studies are rarely mapped to theoretical frameworks. The purpose of this review was to firstly introduce MEG to interested researchers and secondly provide a synopsis of the current state. We divided recent tinnitus research in MEG into study designs using resting state measurements and studies implementing tone stimulation paradigms. The studies were categorized based on their theoretical foundation, and we outlined shortcomings as well as inconsistencies within the different approaches. Finally, we provided future perspectives on how to benefit more efficiently from the enormous potential of MEG. We suggested novel approaches from a theoretical, conceptual, and methodological point of view to allow future research to obtain a more comprehensive understanding of tinnitus and its underlying processes.
Pubmed PDF WebSK Grinn,M Trevino,E Lobarinas
Publication date 27-11-2023
Background External-ear amplification (EEA) has been shown to vary from 5–19 dB-A in large datasets of pediatric, adolescent, and adult human participants. However, variable EEA is an overlooked characteristic that likely plays a role in individual noise-induced hearing loss (NIHL) susceptibility. A noise exposure varying 5–19 dB-A translates to high-EEA individuals theoretically experiencing 3–4 times greater NIHL risk than low-EEA individuals. Objective The purpose of this preliminary analysis was to test the hypothesis that higher EEA is correlated with increased noise-induced threshold shift susceptibility. Design Nine chinchillas were exposed to 4-k Hz octave-band noise at 89 dB-SPL for 24 h. Auditory brainstem response thresholds were obtained pre-exposure, 24-h post-exposure, and 4-week post-exposure. Relationships between EEA and threshold shift were analyzed. Results Open-ear EEA ranged 11–19 dB-SPL, and occluded-ear EEA ranged 10–21 dB-SPL. Higher occluded-ear EEA was correlated with increased NIHL susceptibility (p = 0.04), as was lower body weight (p = 0.01). Male animals exhibited more threshold shift than female animals (p = 0.02), lower body weight than female animals (p = 0.02), and higher occluded-ear EEA (male mean = 18 dB; female mean = 15 dB). Conclusions Taken together, increased threshold shift susceptibility was observed in the smallest animals, animals with the highest occluded-ear EEA, and in male animals (which tended to have higher occluded-ear EEA). Given the established relationship between smaller body size and higher occluded-ear EEA, these preliminary results suggest that body size (and occluded-ear EEA; a function of body size) could be a potential, underlying driver of NIHL susceptibility differences, rather than true sex differences.
Pubmed PDF WebCR Cederroth
Publication date 13-11-2023
PZ Wu,JT O'Malley,MC Liberman
Publication date 13-11-2023
Quantifying the survival patterns of spiral ganglion cells (SGCs), the cell bodies of auditory-nerve fibers, is critical to studies of sensorineural hearing loss, especially in human temporal bones. The classic method of manual counting is tedious, and, although stereology approaches can be faster, they can only be used to estimate total cell numbers per cochlea. Here, a machine-learning algorithm that automatically identifies, counts, and maps the SGCs in digitized images of semi-serial human temporal-bone sections not only speeds the analysis, with no loss of accuracy, but also allows 3D visualization of the SGCs and fine-grained mapping to cochlear frequency. Applying the algorithm to 62 normal-aging human ears shows significantly faster degeneration of SGCs in the basal than the apical half of the cochlea. Comparison to fiber counts in the same ears shows that the fraction of surviving SGCs lacking a peripheral axon steadily increases with age, reaching more than 50% in the apical cochlea and almost 66% in basal regions.
Pubmed PDF WebFT Husain,RA Khan
Publication date 02-11-2023
In advancing our understanding of tinnitus, some of the more impactful contributions in the past two decades have come from human brain imaging studies, specifically the idea of both auditory and extra-auditory neural networks that mediate tinnitus. These networks subserve both the perception of tinnitus and the psychological reaction to chronic, continuous tinnitus. In this article, we review particular studies that report on the nodes and links of such neural networks and their inter-network connections. Innovative neuroimaging tools have contributed significantly to the increased understanding of anatomical and functional connections of attention, emotion-processing, and default mode networks in adults with tinnitus. We differentiate between the neural correlates of tinnitus and those of comorbid hearing loss; surprisingly, tinnitus and hearing loss when they co-occur are not necessarily additive in their impact and, in rare cases, additional tinnitus may act to mitigate the consequences of hearing loss alone on the brain. The scale of tinnitus severity also appears to have an impact on brain networks, with some of the alterations typically attributed to tinnitus reaching significance only in the case of bothersome tinnitus. As we learn more about comorbid conditions of tinnitus, such as depression, anxiety, hyperacusis, or even aging, their contributions to the network-level changes observed in tinnitus will need to be parsed out in a manner similar to what is currently being done for hearing loss or severity. Together, such studies advance our understanding of the heterogeneity of tinnitus and will lead to individualized treatment plans.
Pubmed PDF WebY Wang,KS Abrams,M Youngman,KS Henry
Publication date 05-10-2023
Purpose Loss of auditory nerve afferent synapses with cochlear hair cells, called cochlear synaptopathy, is a common pathology in humans caused by aging and noise overexposure. The perceptual consequences of synaptopathy in isolation from other cochlear pathologies are still unclear. Animal models provide an effective approach to resolve uncertainty regarding the physiological and perceptual consequences of auditory nerve loss, because neural lesions can be induced and readily quantified. The budgerigar, a parakeet species, has recently emerged as an animal model for synaptopathy studies based on its capacity for vocal learning and ability to behaviorally discriminate simple and complex sounds with acuity similar to humans. Kainic acid infusions in the budgerigar produce a profound reduction of compound auditory nerve responses, including wave I of the auditory brainstem response, without impacting physiological hair cell measures. These results suggest selective auditory nerve damage. However, histological correlates of neural injury from kainic acid are still lacking. Methods We quantified the histological effects caused by intracochlear infusion of kainic acid (1 mM; 2.5 µL), and evaluated correlations between the histological and physiological assessments of auditory nerve status. Results Kainic acid infusion in budgerigars produced pronounced loss of neural auditory nerve soma (60% on average) in the cochlear ganglion, and of peripheral axons, at time points 2 or more months following injury. The hair cell epithelium was unaffected by kainic acid. Neural loss was significantly correlated with reduction of compound auditory nerve responses and auditory brainstem response wave I. Conclusion Compound auditory nerve responses and wave I provide a useful index of cochlear synaptopathy in this animal model.
Pubmed PDF WebS Michiels
Publication date 04-10-2023
Somatosensory tinnitus (ST) is a type of tinnitus where changes in somatosensory input from the head-neck area are one of the influencing factors of a patient’s tinnitus. As there are often several influencing factors, identifying a clear somatosensory influence on an individual patient’s tinnitus is often a challenge. Therefore, a decision tree using four clinical criteria has been proposed that can help diagnose ST with an accuracy of 82.2%, a sensitivity of 82.5%, and a specificity of 79%. Once correctly diagnosed, patients can be successfully treated using a musculoskeletal physical therapy treatment. This type of treatment can either be directed at cervical spine dysfunctions, temporomandibular disorders, or both and consists of a combination of counseling, exercises, and manual techniques to restore normal function of the cervical spine and temporomandibular area. Other techniques have been suggested but need further investigation in larger RCTs. In most cases, ST treatment shows a decrease in tinnitus severity or loudness, but in rare cases, total remission of the tinnitus is achieved.
Pubmed PDF WebIS Bhatt,SK Ramadugu,S Goodman,SG Bhagavan,V Ingalls,R Dias,A Torkamani
Publication date 02-10-2023
Purpose Speech-in-noise (SIN) traits exhibit high inter-subject variability, even for healthy young adults reporting normal hearing. Emerging evidence suggests that genetic variability could influence inter-subject variability in SIN traits. Genome-wide association studies (GWAS) have uncovered the polygenic architecture of various adult-onset complex human conditions. Polygenic risk scores (PRS) summarize complex genetic susceptibility to quantify the degree of genetic risk for health conditions. The present study conducted PRS-based association analyses to identify PRS risk factors for SIN and hearing threshold measures in 255 healthy young adults (18–40 years) with self-reported normal hearing. Methods Self-reported SIN perception abilities were assessed by the Speech, Spatial, and Qualities of Hearing Scale (SSQ12). QuickSIN and audiometry (0.25–16 k Hz) were performed on 218 participants. Saliva-derived DNA was used for low-pass whole genome sequencing, and 2620 PRS variables for various traits were calculated using the models derived from the polygenic risk score (PGS) catalog. The regression analysis was conducted to identify predictors for SSQ12, QuickSIN, and better ear puretone averages at conventional (PTA0.5–2), high (PTA4-8), and extended-high (PTA12.5–16) frequency ranges. Results Participants with a higher genetic predisposition to HDL cholesterol reported better SSQ12. Participants with high PRS to dementia revealed significantly elevated PTA4-8, and those with high PRS to atrial fibrillation and flutter revealed significantly elevated PTA12.5–16. Conclusion These results indicate that healthy individuals with polygenic risk of certain health conditions could exhibit a subclinical decline in hearing health measures at young ages, decades before clinically meaningful SIN deficits and hearing loss could be observed. PRS could be used to identify high-risk individuals to prevent hearing health conditions by promoting a healthy lifestyle.
Pubmed PDF WebNA Waring,A Chern,BJ Vilarello,JH Lang,ES Olson,HH Nakajima
Publication date 08-09-2023
Purpose Sheep are used as a large-animal model for otology research and can be used to study implantable hearing devices. However, a method for temporal bone extraction in sheep, which enables various experiments, has not been described, and literature on middle ear access is limited. We describe a method for temporal bone extraction and an extended facial recess surgical approach to the middle ear in sheep. Methods Ten temporal bones from five Hampshire sheep head cadavers were extracted using an oscillating saw. After craniotomy and removal of the brain, a coronal cut was made at the posterior aspect of the orbit followed by a midsagittal cut of the occipital bone and disarticulation of the atlanto-occipital joint. Temporal bones were surgically prepared with an extended facial recess approach. Micro-CT scans of each temporal bone were obtained, and anatomic dimensions were measured. Results Temporal bone extraction was successful in 10/10 temporal bones. Extended facial recess approach exposed the malleus, incus, stapes, and round window while preserving the facial nerve, with the following surgical considerations: minimally pneumatized mastoid; tegmen (superior limit of mastoid cavity) is low-lying and sits below temporal artery; chorda tympani sacrificed to optimize middle ear exposure; incus buttress does not obscure view of middle ear. Distance between the superior aspect of external auditory canal and tegmen was 2.7 (SD 0.9) mm. Conclusion We identified anatomic landmarks for temporal bone extraction and describe an extended facial recess approach in sheep that exposes the ossicles and round window. This approach is feasible for studying implantable hearing devices.
Pubmed PDF WebMA Eckert,FT Husain,D M P Jayakody,W Schlee,CR Cederroth
Publication date 01-08-2023
B Xiong,Z Liu,J Li,X Huang,J Yang,W Xu,YC Chen,Y Cai,Y Zheng
Publication date 01-08-2023
Background Previous studies have demonstrated that tinnitus is associated with neural changes in the cerebral cortex. This study is aimed at investigating the central nervous characteristics of tinnitus patients with different severity by using a rs-EEG. Participants and Methods rs-EEG was recorded in fifty-seven patients with chronic tinnitus and twenty-seven healthy controls. Tinnitus patients were divided into moderate-to-severe tinnitus group and slight-to-mild tinnitus group based on their Tinnitus Handicap Inventory (THI) scores. Source localization and functional connectivity analyses were used to measure the changes in central levels and examine the altered network patterns. The correlation between functional connectivity and tinnitus severity was analyzed. Result Compared to the healthy controls, all tinnitus patients showed significant activation in the auditory cortex (middle temporal lobe, BA 21), while moderate-to-severe tinnitus group showed enhanced connectivity between the parahippocampus and posterior cingulate gyrus. Moreover, the moderate-to-severe tinnitus group had enhanced functional connectivity between auditory cortex and insula compared to the slight-to-mild tinnitus group. The connections between the insula and the parahippocampal and posterior cingulate gyrus were positively correlated with THI scores. Conclusion The current study reveals that patients with moderate-to-severe tinnitus demonstrate greater changes in the central brain areas, including the auditory cortex, insula, parahippocampus and posterior cingulate gyrus. In addition, enhanced connections were found between the insula and the auditory cortex, as well as the posterior cingulate gyrus and the parahippocampus, which suggests abnormality in the auditory network, salience network, and default mode network. Specifically, the insula is the core region of the neural pathway that is composed of the auditory cortex, insula, and parahippocampus/posterior cingulate gyrus. This suggests that the severity of tinnitus is affected by multiple brain regions.
Pubmed PDF WebMR Molis,WJ Bologna,BM Madsen,RK Muralimanohar,CJ Billings
Publication date 01-08-2023
Purpose Speech is characterized by dynamic acoustic cues that must be encoded by the auditory periphery, auditory nerve, and brainstem before they can be represented in the auditory cortex. The fidelity of these cues in the brainstem can be assessed with the frequency-following response (FFR). Data obtained from older adults—with normal or impaired hearing—were compared with previous results obtained from normal-hearing younger adults to evaluate the effects of age and hearing loss on the fidelity of FFRs to tone glides. Method A signal detection approach was used to model a threshold criterion to distinguish the FFR from baseline neural activity. The response strength and temporal coherence of the FFR to tone glides varying in direction (rising or falling) and extent ( \(\nicefrac{1}{3}\) , \(\nicefrac{2}{3}\) , or 1 octave) were assessed by signal-to-noise ratio (SNR) and stimulus–response correlation coefficient (SRCC) in older adults with normal hearing and with hearing loss. Results Significant group mean differences in both SNR and SRCC were noted—with poorer responses more frequently observed with increased age and hearing loss—but with considerable response variability among individuals within each group and substantial overlap among group distributions. Conclusion The overall distribution of FFRs across listeners and stimulus conditions suggests that observed group differences associated with age and hearing loss are influenced by a decreased likelihood of older and hearing-impaired individuals having a detectable FFR response and by lower average FFR fidelity among those older and hearing-impaired individuals who do have a detectable response.
Pubmed PDF WebMA Cheatham
Publication date 01-08-2023
Normal hearing is associated with cochlear nonlinearity. When two tones (f1 and f2) are presented, the intracochlear response contains additional components that can be recorded from the ear canal as distortion product otoacoustic emissions (DPOAEs). Although the most prominent intermodulation distortion component is at 2f1-f2, other cubic distortion products are also generated. Because these measurements are noninvasive, they are used in humans and in animal models to detect hearing loss. This study evaluated how loss of sensitivity affects DPOAEs with frequencies above and below the stimulating primaries, i.e., for upper sideband (USB) components like 2f2-f1 and for lower sideband (LSB) components like 2f1-f2. DPOAEs were recorded in several mouse mutants with varying degrees of hearing loss associated with structural changes to the tectorial membrane (TM), or with loss of outer hair cell (OHC) somatic electromotility due to lack of prestin or to the expression of a non-functional prestin. In mice with changes in sensitivity, magnitude reductions were observed for 2f1-f2 relative to controls with mice lacking prestin showing the greatest changes. In contrast, 2f2-f1 was minimally affected by reductions in cochlear gain due to changes in the TM or by the loss of OHC somatic electromotility. In addition, TM mutants with spontaneous otoacoustic emissions (SOAEs) generated larger responses than controls at 2f2-f1 when its frequency was similar to that for the SOAEs. Although cochlear pathologies appear to affect USB and LSB DPOAEs in different ways, both 2f1-f2 and 2f2-f1 reflect nonlinearities associated with the transducer channels. However, in mice, the component at 2f2-f1 does not appear to receive enhancement due to prestin’s motor action.
Pubmed PDF WebJJA Stultiens,RF Lewis,JO Phillips,A Boutabla,CC Della Santina,R Glueckert,R van de Berg
Publication date 01-08-2023
Patients with bilateral vestibulopathy suffer from a variety of complaints, leading to a high individual and social burden. Available treatments aim to alleviate the impact of this loss and improve compensatory strategies. Early experiments with electrical stimulation of the vestibular nerve in combination with knowledge gained by cochlear implant research, have inspired the development of a vestibular neuroprosthesis that can provide the missing vestibular input. The feasibility of this concept was first demonstrated in animals and later in humans. Currently, several research groups around the world are investigating prototype vestibular implants, in the form of vestibular implants as well as combined cochlear and vestibular implants. The aim of this review is to convey the presentations and discussions from the identically named symposium that was held during the 2021 Mid Winter Meeting of the Association for Research in Otolaryngology, with researchers involved in the development of vestibular implants targeting the ampullary nerves. Substantial advancements in the development have been made. Yet, research and development processes face several challenges to improve this neuroprosthesis. These include, but are not limited to, optimization of the electrical stimulation profile, refining the surgical implantation procedure, preserving residual labyrinthine functions including hearing, as well as gaining regulatory approval and establishing a clinical care infrastructure similar to what exists for cochlear implants. It is believed by the authors that overcoming these challenges will accelerate the development and increase the impact of a clinically applicable vestibular implant.
Pubmed PDF WebGO Bom Braga,A Parrilli,R Zboray,M Bulatović,F Wagner
Publication date 01-08-2023
Purpose The osseous spiral lamina (OSL) is an inner cochlear bony structure that projects from the modiolus from base to apex, separating the cochlear canal into the scala vestibuli and scala tympani. The porosity of the OSL has recently attracted the attention of scientists due to its potential impact on the overall sound transduction. The bony pillars between the vestibular and tympanic plates of the OSL are not always visible in conventional histopathological studies, so imaging of such structures is usually lacking or incomplete. With this pilot study, we aimed, for the first time, to anatomically demonstrate the OSL in great detail and in 3D. Methods We measured width, thickness, and porosity of the human OSL by microCT using increasing nominal resolutions up to 2.5-µm voxel size. Additionally, 3D models of the individual plates at the basal and middle turns and the apex were created from the CT datasets. Results We found a constant presence of porosity in both tympanic plate and vestibular plate from basal turn to the apex. The tympanic plate appears to be more porous than vestibular plate in the basal and middle turns, while it is less porous in the apex. Furthermore, the 3D reconstruction allowed the bony pillars that lie between the OSL plates to be observed in great detail. Conclusion By enhancing our comprehension of the OSL, we can advance our comprehension of hearing mechanisms and enhance the accuracy and effectiveness of cochlear models.
Pubmed PDF WebDL Tucci
Publication date 01-06-2023
The National Institute on Deafness and Other Communication Disorders (NIDCD) recently issued a new strategic plan that describes the institute’s scientific priorities over the next five years. Developed in collaboration with informed stakeholders, the 2023–2027 NIDCD Strategic Plan: Advancing the Science of Communication to Improve Lives creates a unified vision to stimulate discoveries in basic research, model systems, innovative technologies, individualized treatment approaches, scientific data sharing, and translation of research findings into clinical practice. To further accelerate scientific discoveries, the institute encourages collaborations and information sharing among interdisciplinary teams conducting research in these priority areas, and advocates for the utilization of biomedical databases to share scientific findings. NIDCD also welcomes investigator-driven applications that capitalize on advances in basic research to better understand normal and disordered processes; develop or improve model systems to inform research; or facilitate the use of biomedical data utilizing best practices. Through these efforts, NIDCD will continue to conduct and support research that improves the quality of life for the millions of American impacted by conditions affecting hearing, balance, taste, smell, voice, speech, or language.
Pubmed PDF WebAW Accomando,MA Johnson,MA McLaughlin,JA Simmons,AM Simmons
Publication date 01-06-2023
Purpose The echolocating bat is used as a model for studying the auditory nervous system because its specialized sensory capabilities arise from general mammalian auditory percepts such as pitch and sound source localization. These percepts are mediated by precise timing within neurons and networks of the lower auditory brainstem, where the gap junction protein Connexin36 (CX36) is expressed. Gap junctions and electrical synapses in the central nervous system are associated with fast transmission and synchronous patterns of firing within neuronal networks. The purpose of this study was to identify areas where CX36 was expressed in the bat cochlear nucleus to shed light on auditory brainstem networks in a hearing specialist animal model. Methods We investigated the distribution of CX36 RNA throughout the cochlear nucleus complex of the echolocating big brown bat, Eptesicus fuscus, using in situ hybridization. As a qualitative comparison, we visualized Gjd2 gene expression in the cochlear nucleus of transgenic CX36 reporter mice, species that hear ultrasound but do not echolocate. Results In both the bat and the mouse, CX36 is expressed in the anteroventral and in the dorsal cochlear nucleus, with more limited expression in the posteroventral cochlear nucleus. These results are generally consistent with previous work based on immunohistochemistry. Conclusion Our data suggest that the anatomical substrate for CX36-mediated electrical neurotransmission is conserved in the mammalian CN across echolocating bats and non-echolocating mice.
Pubmed PDF WebAM Parra-Perez,JA Lopez-Escamez
Publication date 01-06-2023
Meniere disease (MD) is a rare disorder of the inner ear defined by sensorineural hearing loss (SNHL) associated with episodes of vertigo and tinnitus. The phenotype is variable, and it may be associated with other comorbidities such as migraine, respiratory allergies, and several autoimmune disorders. The condition has a significant heritability according to epidemiological and familial segregation studies. Familial MD is found in 10% of cases, the most frequently found genes being OTOG, MYO7A, and TECTA, previously associated with autosomal dominant and recessive non-syndromic SNHL. These findings suggest a new hypothesis where proteins involved in the extracellular structures in the apical surface of sensory epithelia (otolithic and tectorial membranes) and proteins in the stereocilia links would be key elements in the pathophysiology of MD. The ionic homeostasis of the otolithic and tectorial membranes could be critical to suppress the innate motility of individual hair cell bundles. Initially, focal detachment of these extracellular membranes may cause random depolarization of hair cells and will explain changes in tinnitus loudness or trigger vertigo attacks in early stages of MD. With the progression of the disease, a larger detachment will lead to an otolithic membrane herniation into the horizontal semicircular canal with dissociation in caloric and head impulse responses. Familial MD shows different types of inheritance, including autosomal dominant and compound recessive patterns and implementation of genetic testing will improve our understanding of the genetic structure of MD.
Pubmed PDF WebMR Iyer,R Kalluri
Publication date 01-06-2023
Purpose Nuclear position is precisely orchestrated during cell division, migration, and maturation of cells and tissues. Here we report a previously unrecognized, programmed movement of the nucleus in rat and mouse cochlear inner hair cells (IHCs) coinciding with the functional maturation of inner hair cells around the onset of hearing. Methods We measured hair cell length and nuclear position from confocal scans of immunofluorescence-labeled hair cells from whole-mount cochlear preparations throughout post-natal development. Results In early post-natal days, the IHC experiences a period of sustained growth, during which the nucleus sits at the very basal pole of the cell, far from the apically located mechano-transducing stereocilia, but close to where synapses with primary afferent and efferent neurons are forming. After IHCs reach their final length, the nucleus moves to occupy a new position half-way along the length of the cell. Nuclear translocation begins in the middle turn, completes throughout the cochlea within 2–3 days, and coincides with the emergence of endolymphatic potential, the acquisition of big-conductance potassium channels (BK), and the onset of acoustic hearing. IHCs cultured in-vitro without endolymphatic potential (EP) do not grow, do not express BK, and do not experience nuclear movement. IHCs cultured in high K+ solutions (to simulate EP) grow but do not experience nuclear movement or acquire BK channels. Conclusion Nuclear migration at the onset of hearing is a key step in the morphological maturation of IHCs. Whether this plays a role in functional maturation remains to be explored.
Pubmed PDF WebM Golabbakhsh,X Wang,D MacDougall,J Farrell,T Landry,WRJ Funnell,R Adamson
Publication date 01-06-2023
Purpose Optical coherence tomography (OCT) is an emerging imaging modality which is non-invasive, can be employed in vivo, and can record both anatomy and vibrations. The purpose here is to explore the application of finite-element (FE) modelling to OCT data. Methods We recorded vibrations for three human cadaver middle ears using OCT. We also have X-ray microCT images from the same ears. Three FE models were built based on geometries obtained from the microCT images. The material properties and boundary conditions of the models were obtained from previously reported studies. Results Tympanic-membrane (TM) vibration patterns were computed for the three models and compared with the patterns measured using OCT. Frequency responses were also computed for all three models for several locations in the middle ear and compared with the OCT displacements and with the literature. The three models were compared with each other in terms of geometry and function. Parameter sensitivity analyses were done and the results were compared among the models and with the literature. The simulated TM displacement patterns are qualitatively similar to the OCT results. The simulated displacements are closer to the OCT results for 500 Hz and 1 k Hz but the differences are greater at 2 k Hz. Conclusion This study provides an initial look at the combined use of OCT measurements and FE modelling based on subject-specific anatomy. The geometries and parameters of the existing FE models could be modified for individual patients in the future to help identify abnormalities in the middle ear.
Pubmed PDF Web