Finite Element Modeling of Sound Transmission Based on Micro-Computer Tomography for Human Ear

An accurate finite element (FE) model of the human ear can help in understanding the physiological mechanismof human ear and facilitate the design of implantable hearing devices. In this paper,a FE modelof the human ear consisting of the external ear canal, middle ear, and cochlea was developed. The geometry of the external ear canal and middle ear model was based on a fresh specimen of human temporal boneviamicro-computer tomography imaging. A harmonic sound pressure of 90 dB SPL was applied in the ear canal and the multi-field coupled FE analysis was conductedamong the ear canal air, cochlea fluid, and middle ear and cochlea structures. The results were compared with the established physiological data. The satisfactory agreements between the model and published experimental measurementsindicate the middle ear and cochlea functions can be well simulated and further application in terms of human ear can be achieved by the model.

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Finite element modeling of human ear with external ear canal and middle ear cavity

Proceedings of the Second Joint 24th Annual Conference and the Annual Fall Meeting of the Biomedical Engineering Society] [Engineering in Medicine and Biology ◽

10.1109/iembs.2002.1134484 ◽

2003 ◽

Cited By ~ 7

Author(s):

R.Z. Gan ◽

Q. Sun

Keyword(s):

Finite Element ◽

Finite Element Modeling ◽

Middle Ear ◽

External Ear ◽

Ear Canal ◽

Element Modeling ◽

External Ear Canal ◽

Human Ear

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3D Finite Element Modeling of Blast Wave Transmission From the External Ear to a Spiral Cochlea

Journal of Biomechanical Engineering ◽

10.1115/1.4051925 ◽

2021 ◽

Author(s):

Marcus Brown ◽

John Bradshaw ◽

Rong Z. Gan

Keyword(s):

Finite Element ◽

Middle Ear ◽

Basilar Membrane ◽

Transverse Motion ◽

Fe Model ◽

Ear Canal ◽

Blast Overpressure ◽

Stapes Footplate ◽

Human Ear ◽

Temporal Bones

Abstract Blast-induced injuries affect the health of veterans, in which the auditory system is often damaged, and blast-induced auditory damage to the cochlea is difficult to quantify. A recent study modeled blast overpressure (BOP) transmission throughout the ear utilizing a straight, two-chambered cochlea, but the spiral cochlea's response to blast exposure has yet to be investigated. In this study, we utilized a human ear finite element (FE) model with a spiraled, two-chambered cochlea to simulate the response of the anatomical structural cochlea to BOP exposure. The FE model included an ear canal, middle ear, and two and half turns of two-chambered cochlea and simulated a BOP from the ear canal entrance to the spiral cochlea in a transient analysis utilizing fluid-structure interfaces. The model's middle ear was validated with experimental pressure measurements from the outer and middle ear of human temporal bones. The results showed high stapes footplate displacements up to 28.5µm resulting in high intracochlear pressures and basilar membrane (BM) displacements up to 43.2µm from a BOP input of 30.7kPa. The cochlea's spiral shape caused asymmetric pressure distributions as high as 4kPa across the cochlea's width and higher BM transverse motion than that observed in a similar straight cochlea model. The developed spiral cochlea model provides an advancement from the straight cochlea model to increase the understanding of cochlear mechanics during blast and progresses towards a model able to predict potential hearing loss after blast.

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Chapter-12 Middle Ear Dissection and External Ear Canal Widening

Step by Step� Temporal Bone Dissection ◽

10.5005/jp/books/12134_12 ◽

2014 ◽

pp. 63-67

Author(s):

Gauri Belsare

Keyword(s):

Middle Ear ◽

External Ear ◽

Ear Canal ◽

External Ear Canal

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Side-Hole Suction for Ear Surgery

Otolaryngology ◽

10.1177/019459987908700121 ◽

1979 ◽

Vol 87 (1) ◽

pp. 87-88 ◽

Cited By ~ 2

Author(s):

N. Wendell Todd

Keyword(s):

Soft Tissue ◽

Middle Ear ◽

Surgical Trauma ◽

External Ear ◽

Ear Canal ◽

Ear Surgery ◽

Graft Placement ◽

Side Hole ◽

External Ear Canal

Surgical trauma to the soft tissue of the external ear canal and middle ear increases inflammation and scarring. A side-hole suction tip has been found to minimize suction-tip trauma, preclude the need to aspirate through synthetic sponge or cotton, and facilitate graft placement.

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Evaluation of Round Window Stimulation Performance in Otosclerosis Using Finite Element Modeling

Computational and Mathematical Methods in Medicine ◽

10.1155/2016/3603207 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Shanguo Yang ◽

Dan Xu ◽

Xiaole Liu

Keyword(s):

Finite Element ◽

Middle Ear ◽

Bone Growth ◽

Round Window ◽

Element Model ◽

Annular Ligament ◽

Fe Model ◽

Sound Stimulation ◽

Partial Fixation ◽

Human Ear

Round window (RW) stimulation is a new type of middle ear implant’s application for treating patients with middle ear disease, such as otosclerosis. However, clinical outcomes show a substantial degree of variability. One source of variability is the variation in the material properties of the ear components caused by the disease. To investigate the influence of the otosclerosis on the performance of the RW stimulation, a human ear finite element model including middle ear and cochlea was established based on a set of microcomputerized tomography section images of a human temporal bone. Three characteristic changes of the otosclerosis in the auditory system were simulated in the FE model: stapedial annular ligament stiffness enlargement, stapedial abnormal bone growth, and partial fixation of the malleus. The FE model was verified by comparing the model-predicted results with published experimental measurements. The equivalent sound pressure (ESP) of RW stimulation was calculated via comparing the differential intracochlear pressure produced by the RW stimulation and the normal eardrum sound stimulation. The results show that the increase of stapedial annular ligament and partial fixation of the malleus decreases RW stimulation’s ESP prominently at lower frequencies. In contrast, the stapedial abnormal bone growth deteriorates RW stimulation’s ESP severely at higher frequencies.

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External ear canal cholesteatoma after ventilation tube insertion and mastoidectomy

Vojnosanitetski pregled ◽

10.2298/vsp1204363d ◽

2012 ◽

Vol 69 (4) ◽

pp. 363-366 ◽

Cited By ~ 1

Author(s):

Dragoslava Djeric ◽

Milan Jovanovic ◽

Ivan Baljosevic ◽

Srbislav Blazic ◽

Milanko Milojevic

Keyword(s):

Tympanic Membrane ◽

Middle Ear ◽

Membrane Surface ◽

Tube Placement ◽

External Ear ◽

Ventilation Tube ◽

Ear Canal ◽

Tube Insertion ◽

Tissue Mass ◽

External Ear Canal

Introduction. Etiopathogenetically, there are two types of chollesteatomas: congenital, and acquired. Numerous theories in the literature try to explain the nature of the disease, however, the question about cholesteatomas remain still unanswered. The aim of the study was to present a case of external ear canal cholesteatoma (EEC) developed following microsurgery (ventilation tube insertion and mastoidectomy), as well as to point ant possible mechanisms if its development. Case report. A 16-yearold boy presented a 4-month sense of fullness in the ear and otalgia on the left side. A year before, mastoidectomy and posterior atticotomy were performed with ventilation tube placement due to acute purulent mastoiditis. Diagnosis was based on otoscopy examination, audiology and computed tomography (CT) findings. CT showed an obliterative soft-tissue mass completely filled the external ear canal with associated erosion of subjacent the bone. There were squamous epithelial links between the canal cholesteatoma and lateral tympanic membrane surface. They originated from the margins of tympanic membrane incision made for a ventilation tube (VT) insertion. The position of VT was good as well as the aeration of the middle ear cavity. The tympanic membrane was intact and of normal appearance without middle ear extension or mastoid involvement of cholesteatoma. Cholesteatoma and ventilation tube were both removed. The patient recovered without complications and shortly audiology revealed hearing improving. Follow-up 2 years later, however, showed no signs of the disease. Conclusion. There could be more than one potential delicate mechanism of developing EEC in the ear with VT insertion and mastoidectomy. It is necessary to perform routine otologic surveillance in all patients with tubes. Affected ear CT scan is very helpful in showing the extent of cholesteatoma and bony defects, which could not be assessed by otoscopic examination alone.

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