LDV measurement of bird ear vibrations to determine inner ear impedance and middle ear power flow

The effect of platelet activating factor (PAF) was studied to elucidate its role in the pathogenesis of otitis media and sensorineural hearing loss. The PAF alone did not induce a reduction of ciliary activity of the cultured middle ear mucosa. However, a dose-dependent decrease in ciliary activity was observed in the presence of the medium containing both PAF and macrophages. Intravenous injection of PAF did not induce dysfunction of the mucociliary system or morphologic changes of epithelium in the tubotympanum, but cytoplasmic vacuolization and ballooning were observed in the inner ear within 1 hour after injection of PAF. In contrast, intratympanic injection of PAF induced mucociliary dysfunction and some pathologic changes in the tubotympanum. Intratympanic inoculation of PAF induced no pathologic findings in the inner ear. These results suggest that PAF is at least partially involved in the pathogenesis of certain middle ear diseases such as otitis media with effusion. Additionally, PAF might be involved in the pathogenesis of some types of unexplained sensorineural hearing loss.

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Common drugs used in ENT

Oxford Handbook of ENT and Head and Neck Surgery ◽

10.1093/med/9780199550791.003.21 ◽

2009 ◽

pp. 347-350

Author(s):

Rogan Corbridge ◽

Nicholas Steventon

Keyword(s):

Inner Ear ◽

Tympanic Membrane ◽

Middle Ear ◽

Otitis Externa ◽

Round Window ◽

Acid Reflux ◽

Tympanic Membrane Perforation ◽

Active Infection ◽

Middle Ear Mucosa ◽

Membrane Perforation

Drugs used in the ear 348 Drugs used in the nose 349 Drugs used in the treatment of acid reflux 350 This group of drugs is widely used for the treatment of otitis externa. Otitis externa 2 drops tds for 10 days Presence of grommet or tympanic membrane perforation due to aminoglycoside ototoxicity in the inner ear. Risk thought to be low in the presence of active infection where the middle-ear mucosa is swollen and the antibiotic is unlikely to reach the inner ear via the round window...

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Study on the Prosthesis Structural Design and Vibration Characteristics Based on the Conduction Effect of Human Middle Ear

Applied Bionics and Biomechanics ◽

10.1155/2020/4250265 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Wu Ren ◽

Huijuan Yan ◽

Yi Yu ◽

Jinghong Ren ◽

Jinlong Chang ◽

...

Keyword(s):

Frequency Response ◽

Inner Ear ◽

Tympanic Membrane ◽

Middle Ear ◽

Transmission Function ◽

Ossicular Chain ◽

Sound Signal ◽

Sound Perception ◽

Response Characteristics ◽

Middle Ear Prosthesis

As a bridge from the sound signal in the air to the sound perception of the inner ear auditory receptor, the tympanic membrane and ossicular chain of the middle ear transform the sound signal in the outer ear through two gas-solid and solid-liquid conversions. In addition, through the lever principle formed by three auditory ossicle structure, the sound was concentrated and amplified to the inner ear. However, the sound transmission function of the middle ear will be decreased by disease, genetic, or trauma. Hence, using middle ear prosthesis to replace the damaged ossicles can restore the conduction function. The function realization of middle ear prosthesis depends on the vibration response of the prosthesis from the tympanic membrane to the stapes plate on the human auditory perception frequency, which is affected by the way the prosthesis combined with the tympanic membrane, the material, and the geometric shape. In this study, reasonable prosthetic structures had been designed for different types of ossicular chain injuries, and the frequency response characteristics were analyzed by the finite element method then. Moreover, in order to achieve better vibration frequency response, a ball structure was designed in the prosthesis to simulate its amplification function. The results showed that the middle ear prostheses constructed by different injury types can effectively transfer vibration energy. In particular, the first- and second-order resonant frequencies and response amplitudes are close to each other when ball structure models of different materials are added. Instead, the resonance frequency of the third stage formed by aluminum alloy ball materials is larger than that of the other two, which showed good response features.

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Influence of Middle Ear Immune Response on the Immunological State and Function of the Inner Ear

The Laryngoscope ◽

10.1288/00005537-199202000-00013 ◽

1992 ◽

Vol 102 (2) ◽

pp. 177???181 ◽

Cited By ~ 9

Author(s):

B. Gloddek ◽

Kerstin Lamm ◽

K. Haslov

Keyword(s):

Immune Response ◽

Inner Ear ◽

Middle Ear ◽

And Function

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Thyroid Hormone Receptors Control Developmental Maturation of the Middle Ear and the Size of the Ossicular Bones

Endocrinology ◽

10.1210/en.2011-1834 ◽

2012 ◽

Vol 153 (3) ◽

pp. 1548-1560 ◽

Cited By ~ 22

Author(s):

Emily A. Cordas ◽

Lily Ng ◽

Arturo Hernandez ◽

Masahiro Kaneshige ◽

Sheue-Yann Cheng ◽

...

Keyword(s):

Thyroid Hormone ◽

Inner Ear ◽

Middle Ear ◽

Hormone Receptors ◽

Dominant Negative ◽

Thyroid Hormone Receptors ◽

Auditory Thresholds ◽

Auditory Development ◽

Genes Encoding

Thyroid hormone is critical for auditory development and has well-known actions in the inner ear. However, less is known of thyroid hormone functions in the middle ear, which contains the ossicles (malleus, incus, stapes) that relay mechanical sound vibrations from the outer ear to the inner ear. During the later stages of middle ear development, prior to the onset of hearing, middle ear cavitation occurs, involving clearance of mesenchyme from the middle ear cavity while the immature cartilaginous ossicles attain appropriate size and ossify. Using in situ hybridization, we detected expression of Thra and Thrb genes encoding thyroid hormone receptors α1 and β (TRα1 and TRβ, respectively) in the immature ossicles, surrounding mesenchyme and tympanic membrane in the mouse. Thra+/PV mice that express a dominant-negative TRα1 protein exhibited deafness with elevated auditory thresholds and a range of middle ear abnormalities including chronic persistence of mesenchyme in the middle ear into adulthood, markedly enlarged ossicles, and delayed ossification of the ossicles. Congenitally hypothyroid Tshr−/− mice and TR-deficient Thra1−/−;Thrb−/− mice displayed similar abnormalities. These findings demonstrate that middle ear maturation is TR dependent and suggest that the middle ear is a sensitive target for thyroid hormone in development.

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The prognostic influence of pre-surgery bone conduction values on the improvement of hearing in patients treated surgically as a result of middle-ear conditions

Otolaryngologia Polska ◽

10.5604/01.3001.0014.5919 ◽

2020 ◽

Vol 74 (6) ◽

pp. 1-5

Author(s):

Katarzyna Job ◽

Jacek Składzień

Keyword(s):

Inner Ear ◽

Hearing Impairment ◽

Middle Ear ◽

Pure Tone ◽

Bone Conduction ◽

Threshold Value ◽

Surgical Operation ◽

Middle Ear Mechanics ◽

Prognostic Importance ◽

Mechanical Influence

Background The influence of the mechanics of the middle ear on the function of the inner ear has been studied for many years. Among surgeries performed in the middle-ear area, those restoring full functionality of the system transmitting sound inside the middle ear may be pointed out as those fully restoring the mechanical influence of the middle ear on the function of the inner ear. Aim: The aim of the performed analysis is to find the prognostic importance of measured pre-surgery values of bone conduction on the improvement of hearing in patients operated as a result of middle-ear disorders. Methods The analysis included 271 patients hospitalised and operated on due to otosclerosis or perforation of the tympanic membrane between 2016 and 2019. Only patients who had not had a surgical operation within the middle ear prior to the study were included. An audiological assessment was performed with the use of pure tone thresholds audiometry. Results A beneficial influence of the performed surgery on the improvement of bone conduction was observed in patients, in which the average threshold value of bone conduction measured before the surgery did not exceed 40 dB. In cases of the perceptive component of hearing impairment being higher than 40 dB, no statistically significant, beneficial influence of a performed stapedotomy or myringoplasty on the change of bone conduction thresholds was observed. Conclusion The perception component of hearing impairment up to 40 dB indicates bone conduction improvement after surgical restoration of the influence of middle-ear mechanics on the inner ear in patients treated as a result of otosclerosis, as well as of eardrum perforation.

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Effects of Otitis Media on Extended High-Frequency Hearing in Children

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949310200101 ◽

1993 ◽

Vol 102 (1) ◽

pp. 1-5 ◽

Cited By ~ 124

Author(s):

Robert H. Margolis ◽

Joni R. Rykken ◽

Lisa L. Hunter ◽

G. Scott Giebink

Keyword(s):

Inner Ear ◽

Otitis Media ◽

Middle Ear ◽

High Frequency ◽

Good Test ◽

Recurrent Otitis Media

Extended high-frequency (EHF) hearing was studied in children with and without histories of chronic or recurrent otitis media (OM). The EHF thresholds were found to have good test-retest repeatability. Children with OM histories had poorer EHF hearing than children without OM histories. The EHF hearing in OM children appeared to be related to OM severity. Children with residual tympanometric abnormalities had poorer EHF hearing than OM children with normal middle ear function. The results suggest evidence for middle ear and inner ear components of EHF hearing losses in children with OM.

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Functional Patency of the Cochlear Aqueduct

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948209100219 ◽

1982 ◽

Vol 91 (2) ◽

pp. 209-215 ◽

Cited By ~ 48

Author(s):

Björn Carlborg ◽

Barbara Densert ◽

Ove Densert

Keyword(s):

Cerebrospinal Fluid ◽

Inner Ear ◽

Middle Ear ◽

Ambient Pressure ◽

Ear Canal ◽

Cochlear Aqueduct ◽

Pressure Release ◽

Release Capacity ◽

Before And After ◽

Pressure Changes

The perilymphatic (P P) and cerebrospinal fluid (P CSF) pressures were investigated in relation to pressure variations in the ear canal, middle ear and intracranial compartment before and after occlusion of the cochlear aqueduct (CA). Experiments using intracranial infusion showed that the CA was responsible for a perfect hydrodynamic balance between the CSF and the perilymph. There are indications of additional pressure release factors but their capacities were not sufficient to prevent the appearance of a longstanding and substantial pressure gradient following occlusion of the CA. A gradual P P build-up, from zero to its original level after the CA was opened and occluded, indicated perilymph production within the labyrinth. Investigation of pressure transfer from the ear canal and middle ear to the perilymph showed that the CA was the major pressure release route from the cochlea. Occlusion of the CA reduced the compliance of the inner ear and severely reduced the pressure release capacity. In such a situation the inner ear is almost incapable of equilibrating ambient pressure changes.

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