Study of optimal evaluation procedure of ossicular mobility: Numerical analysis using FE-model of human middle ear

Abstract The dynamics of the human middle ear (ME) has been studied in the past using several computational and experimental approaches in order to observe the effect on hearing of different conditions, such as conductive disease, corrective surgery, or implantation of a middle ear prosthesis. Multibody (MB) models combine the analysis of flexible structures with rigid body dynamics, involving fewer degrees-of-freedom (DOF) than finite element (FE) models, but a more detailed description than traditional 1D lumped parameter (LP) models. This study describes the reduction of a reference FE model of the human middle ear to a MB model and compares the results obtained considering different levels of model simplification. All models are compared by means of the frequency response of the stapes velocity versus sound pressure at the tympanic membrane (TM), as well as the system natural frequencies and mode shapes. It can be seen that the flexibility of the ossicles has a limited impact on the system frequency response function (FRF) and modes, and the stiffness of the tendons and ligaments only plays a role when above certain levels. On the other hand, the restriction of the stapes footplate movement to a piston-like behavior can considerably affect the vibrational modes, while constraints to the incudomalleolar joint (IMJ) and incudostapedial joint (ISJ) can have a strong impact on the system FRF.

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Are mucin genes yet to be cloned expressed by human middle ear mucosa?

Clinical Otolaryngology ◽

10.1046/j.1365-2273.1998.0135c.x ◽

1998 ◽

Vol 23 (3) ◽

pp. 265-265 ◽

Cited By ~ 1

Author(s):

Hutton ◽

Birchall ◽

French ◽

Kubba ◽

Severn ◽

...

Keyword(s):

Middle Ear ◽

Middle Ear Mucosa ◽

Mucin Genes ◽

Human Middle Ear

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Immunohistochemical and qPCR Detection of SARS-CoV-2 in the Human Middle Ear Versus the Nasal Cavity: Case Series

Head and Neck Pathology ◽

10.1007/s12105-021-01378-6 ◽

2021 ◽

Author(s):

Arwa Kurabi ◽

Kwang Pak ◽

Adam S. DeConde ◽

Allen F. Ryan ◽

Carol H. Yan

Keyword(s):

Nasal Cavity ◽

Middle Ear ◽

Viral Infections ◽

Case Series ◽

Middle Ear Mucosa ◽

Viral Receptor ◽

Tissue Samples ◽

Angiotensin Converting Enzyme 2 ◽

Nasal Tissue ◽

Human Middle Ear

AbstractViral infections have already been implicated with otitis media and sudden sensorineural hearing loss. However, the pathophysiology of COVID-19 as it relates to otologic disorders is not well-defined. With the spread of SARS-CoV-2, it is important to evaluate its colonization of middle ear mucosa. Middle ear and nasal tissue samples for quantitative RT-PCR and histologic evaluations were obtained from post-mortem COVID-19 patients and non-diseased control patients. Here we present evidence that SARS-CoV-2 colonizes the middle ear epithelium and co-localizes with the primary viral receptor, angiotensin-converting enzyme 2 (ACE2). Both middle ear and nasal epithelial cells show relatively high expression of ACE2, required for SARS-CoV-2 entry. The epithelial cell adhesion molecule (EpCAM) was use as a biomarker of epithelia. Furthermore, we found that the viral load in the middle ear is lower than that present in the nasal cavity.

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Influenza-Induced Inflammation Drives Pneumococcal Otitis Media

Infection and Immunity ◽

10.1128/iai.01278-12 ◽

2013 ◽

Vol 81 (3) ◽

pp. 645-652 ◽

Cited By ~ 43

Author(s):

Kirsty R. Short ◽

Patrick C. Reading ◽

Lorena E. Brown ◽

John Pedersen ◽

Brad Gilbertson ◽

...

Keyword(s):

Otitis Media ◽

Middle Ear ◽

Influenza A ◽

Pneumococcal Disease ◽

Influenza Viruses ◽

Dependent Manner ◽

Proinflammatory Response ◽

Content Type ◽

Infant Mouse ◽

Human Middle Ear

ABSTRACTInfluenza A virus (IAV) predisposes individuals to secondary infections with the bacteriumStreptococcus pneumoniae(the pneumococcus). Infections may manifest as pneumonia, sepsis, meningitis, or otitis media (OM). It remains controversial as to whether secondary pneumococcal disease is due to the induction of an aberrant immune response or IAV-induced immunosuppression. Moreover, as the majority of studies have been performed in the context of pneumococcal pneumonia, it remains unclear how far these findings can be extrapolated to other pneumococcal disease phenotypes such as OM. Here, we used an infant mouse model, human middle ear epithelial cells, and a series of reverse-engineered influenza viruses to investigate how IAV promotes bacterial OM. Our data suggest that the influenza virus HA facilitates disease by inducing a proinflammatory response in the middle ear cavity in a replication-dependent manner. Importantly, our findings suggest that it is the inflammatory response to IAV infection that mediates pneumococcal replication. This study thus provides the first evidence that inflammation drives pneumococcal replication in the middle ear cavity, which may have important implications for the treatment of pneumococcal OM.

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