Effect of Increased Inner Ear Pressure on Middle Ear Mechanics

1998 ◽  
Vol 118 (5) ◽  
pp. 703-708 ◽  
Author(s):  
Eugene N. Myers ◽  
Shingo Murakami ◽  
Kiyofumi Gyo ◽  
Richard L. Goode
Keyword(s):  
Inner Ear ◽  
Phase Angle ◽  
Middle Ear ◽  
Major Effect ◽  
Measuring System ◽  
Annular Ligament ◽  
Middle Ear Mechanics ◽  
Stapes Footplate ◽  
Temporal Bones ◽  
Inner Ear Pressure

Velocity of malleus, umbo, and stapes footplate in response to stepwise increases up to +400 mm H2O in hydrostatic pressure of the inner ear was investigated in 10 fresh human temporal bones by using a laser Doppler interferometer. The sound-pressure input was 114 dB SPL, and the frequency range was 0.4 to 5.0 kHz. Static displacement of these sites was also measured by a video measuring system. When the inner ear pressure was increased, the malleus and stapes moved outward. Amplitude of umbo velocity decreased below 1.0 kHz with a slight increase around 2.0 kHz, whereas stapes velocity decreased at all frequencies with the major effect below 1.0 kHz. The phase angle of malleus umbo velocity advanced markedly in response to the increased inner ear pressure between 1.0 and 1.4 kHz. Change in the vibration of the umbo was thought to be primarily caused by an increased stiffness of the middle ear conduction system, and that of the stapes was caused by distention of the annular ligament and increased cochlear impedance produced by the increased inner ear pressure. These changes in TM vibration and its phase angle may help detect indirectly an elevation of inner ear pressure. (Otolaryngol Head Neck Surg 1998;118:703–8.)

Effect of increased inner ear pressure on middle ear mechanics☆☆☆★

1998 ◽  
Vol 118 (5) ◽  
pp. 703-708 ◽  
Author(s):  
SHINGO MURAKAMI ◽  
KIYOFUMI GYO ◽  
RICHARD L. GOODE
Keyword(s):  
Inner Ear ◽  
Middle Ear ◽  
Middle Ear Mechanics ◽  
Inner Ear Pressure

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

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.

Optical coherence tomography of the oval window niche

2009 ◽  
Vol 123 (6) ◽  
pp. 603-608 ◽  
Author(s):  
T Just ◽  
E Lankenau ◽  
G Hüttmann ◽  
H W Pau
Keyword(s):  
Optical Coherence Tomography ◽  
Middle Ear ◽  
Imaging Modality ◽  
Oval Window ◽  
Annular Ligament ◽  
Middle Ear Surgery ◽  
Optical Coherence ◽  
Ear Surgery ◽  
Temporal Bones

AbstractObjective:Optical coherence tomography was used to study the stapes footplate, both in cadaveric temporal bones and during middle-ear surgery.Materials and methods:Optical coherence tomography was conducted on five temporal bone preparations (from two children and three adults) and in eight patients during middle-ear surgery. A specially equipped operating microscope with integrated spectral domain optical coherence tomography apparatus was used for standard middle-ear surgical procedures.Results:This optical coherence tomography investigation enabled in vivo visualisation and documentation of the annular ligament, the different layers of the footplate and the inner-ear structures, both in non-fixed and fixed stapes footplates. In cases of otosclerosis and tympanosclerosis, an inhomogeneous and irregularly thickened footplate was found, in contrast to the appearance of non-fixed footplates. In both fixed and non-fixed footplates, there was a lack of visualisation of the border between the footplate and the otic capsule.Conclusions:Investigation of the relatively new technology of optical coherence tomography indicated that this imaging modality may assist the ear surgeon to assess the oval window niche intra-operatively.

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

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.

The ear

2021 ◽  
pp. 497-518
Author(s):  
Daniel R. van Gijn ◽  
Jonathan Dunne
Keyword(s):  
Inner Ear ◽  
Temporal Bone ◽  
Middle Ear ◽  
Semicircular Canals ◽  
Lateral Wall ◽  
Oval Window ◽  
External Ear ◽  
Membranous Labyrinth ◽  
Stapes Footplate ◽  
Petrous Temporal Bone

The delicate yet definitive deflections of the pinna (wing/fin) of the external ear contribute to the collection of sound. The external acoustic meatus is responsible for the transmission of sounds to the tympanic membrane, which in turn separates the external ear from the middle ear. The middle ear is an air filled (from the nasopharynx via the eustachian tube), mucous membrane lined space in the petrous temporal bone. It is separated from the inner ear by the medial wall of the tympanic cavity – bridged by the trio of ossicles. The inner ear refers to the bony and membranous labyrinth and their respective contents. The osseus labyrinth lies within the petrous temporal bone. It consists of the cochlea anteriorly, semicircular canals posterosuperiorly and intervening vestibule – the entrance hall to the inner ear whose lateral wall bears the oval window occupied by the stapes footplate.

Temporal Bone Findings in Cases of Salt Water Drowning

1983 ◽  
Vol 92 (2) ◽  
pp. 134-136 ◽  
Author(s):  
George Kelemen
Keyword(s):  
Inner Ear ◽  
Temporal Bone ◽  
Middle Ear ◽  
Salt Water ◽  
Round Window ◽  
Scuba Diving ◽  
Serial Sections ◽  
Histopathological Findings ◽  
Histopathological Features ◽  
Temporal Bones

The otologic literature contains no description of the histopathological features of temporal bones of persons who perished in drowning accidents. Three temporal bones from two fatal cases of drowning were studied in serial sections. Two temporal bones were from a man aged 31 years who collapsed after scuba diving and died three days later. One temporal bone was from a 32-year-old man, serving in the navy, who drove his car, probably accidentally, into the sea and drowned in it. Histopathological findings appeared to be similar in the two cases. Diffuse hemorrhage was evident throughout the middle ear and inner ear. The tympanic and round window membranes appeared to be intact although hemorrhage had occurred within the tissue layers of the membranes. This finding contrasts with observations of ruptured membranes by other investigators.

Effect of Aspiration of Perilymph during Stapes Surgery on the Endocochlear Potential of Guinea Pig

2011 ◽  
Vol 145 (5) ◽  
pp. 801-805 ◽  
Author(s):  
Ryoukichi Ikeda ◽  
Kazuhiro Nakaya ◽  
Hidetoshi Oshima ◽  
Takeshi Oshima ◽  
Tetsuaki Kawase ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Guinea Pig ◽  
Inner Ear ◽  
Oval Window ◽  
Stapes Surgery ◽  
Partial Recovery ◽  
Cochlear Function ◽  
Stapes Footplate ◽  
Guinea Pig Model ◽  
Temporal Bones

Objective. Suction applied to the vestibule through the oval window during stapes surgery is considered a primary risk for postoperative sensorineural hearing impairment. This study investigated the mechanism of acute phase change in cochlear function caused by aspiration of the opened oval window. Study Design. Guinea pig model. Setting. Academic hospital laboratory. Subjects and Methods. Guinea pigs were divided into 3 groups: stapes footplate removed without suctioning (6 animals), with indirect suctioning (5 animals), and with direct suctioning of the vestibular perilymph (6 animals). Endocochlear potentials (EPs) were measured at the second turn of the cochlea, and temporal bones were examined histologically. Results. Removal of the stapes footplate without suctioning caused little change in the EP (original value, 80.12 ± 3.52 mV), indirect suctioning caused minor decline of the EP of 9.14 ± 1.84 mV, and partial recovery ensued, whereas direct but gentle suctioning, resulting in dry vestibule, caused reduction in the EP of 16.38 ± 6.63 mV. Recovery was not observed or incomplete. No animals showed profound decrease in the EP. Conclusion. Gentle suctioning and removal of the vestibular perilymph can cause a mild decrease in the EP even without damaging the inner ear structures. Therefore, suctioning of the perilymph should be avoided during stapes surgery because acute hearing loss can result even without damaging the inner ear structures. However, hearing loss may not be profound, if suctioning is not vigorous enough to cause damage to the inner ear structures.

The Role of Pars Flaccida in Human Middle Ear Sound Transmission

1988 ◽  
Vol 98 (4) ◽  
pp. 310-314 ◽  
Author(s):  
Hiroshi Aritomo ◽  
Richard L. Goode ◽  
James Gonzalez
Keyword(s):  
Middle Ear ◽  
Sound Transmission ◽  
Measuring System ◽  
Human Beings ◽  
Pars Flaccida ◽  
Acoustic Insulation ◽  
Before And After ◽  
Temporal Bones ◽  
A Minor

The role of the pars flaccida in middle ear sound transmission was studied with the use of twelve otoscopically normal, fresh, human temporal bones. Peak-to-peak umbo displacement in response to a constant sound pressure level at the tympanic membrane was measured with a noncontacting video measuring system capable of repeatable measurements down to 0.2 micron. Measurements were made before and after pars flaccida modifications at 18 frequencies between 100 and 4000 Hz. Four pars flaccida modifications were studied: (1) acoustic insulation of the pars flaccida to the ear canal with a silicone rubber baffle, (2) stiffening the pars flaccida with cyanoacrylate cement, (3) decreasing the tension of the pars flaccida with a nonperforating incision, and (4) perforation of the pars flaccida. All of the modifications (except the perforation) had a minimal effect on umbo displacement; this seems to imply that the pars flaccida has a minor acoustic role in human beings.

Temporal Bone Histopathology in Charge Association

2002 ◽  
Vol 111 (5) ◽  
pp. 397-401 ◽  
Author(s):  
Shin-Ichi Haginomori ◽  
Makoto Miura ◽  
Isamu Sando ◽  
Margaretha L. Casselbrant
Keyword(s):  
Inner Ear ◽  
Temporal Bone ◽  
Middle Ear ◽  
Congenital Heart ◽  
The Other ◽  
Otologic Surgery ◽  
Charge Association ◽  
Ear Anomalies ◽  
Temporal Bones ◽  
Central Nervous System Anomalies

Three temporal bones obtained at autopsy from 2 patients with CHARGE association (Coloboma, congenital Heart disease, Atresia of choanae, mental Retardation and/or central nervous system anomalies, Genital hypoplasia, and Ear anomalies) were examined histopathologically. Both temporal bones from 1 patient showed multiple anomalies in the middle ear, inner ear, and facial nerve. However, the temporal bone obtained from the other patient showed almost normal structures in the inner ear, middle ear, and eustachian tube. These results are different from those of 2 previous reports of temporal bone histopathology regarding CHARGE association. This difference suggests that CHARGE association may arise not from one etiopathogenetic factor, but from complex factors. Special attention to dehiscent facial canal and perilymphatic gusher during otologic surgery in patients with CHARGE association is discussed.

How does Prosthesis Head Size Affect Vibration Transmission in Ossiculoplasty?

2007 ◽  
Vol 137 (1) ◽  
pp. 70-73 ◽  
Author(s):  
Manohar Bance ◽  
Alfredo Campos ◽  
Lillian Wong ◽  
David P. Morris ◽  
Rene van Wijhe
Keyword(s):  
Tympanic Membrane ◽  
Temporal Bone ◽  
Middle Ear ◽  
Laser Doppler Vibrometer ◽  
Head Size ◽  
Systematic Effect ◽  
Acoustic Frequency ◽  
Vibration Transmission ◽  
Stapes Footplate ◽  
Temporal Bones

OBJECTIVES: The transmission of vibrations from the tympanic membrane to the stapes footplate by an ossicular reconstruction prosthesis is affected by the size of the prosthesis head. We sought to determine if augmenting or reducing the head size of prosthesis had a systematic effect on transmission of vibrations to the stapes. STUDY DESIGN: We conducted a fresh cadaveric temporal bone middle ear study. METHODS: The incus was replaced with a prosthesis using a tympanic membrane to stapes head (TASH)-type hydroxyapatite prosthesis in nine fresh cadaveric temporal bones. Three prosthesis head sizes were created: unaltered, reduced, and augmented. Stapes vibrations were measured with a laser Doppler vibrometer in response to acoustic frequency chirps at 90 dB SPL. RESULTS: All three head size prostheses resulted in smaller stapes vibrations than the intact ear. There was no difference in the vibration transmission between the three different head sizes. All prostheses showed a vibration loss of 10 to 15 dB compared to the intact ear. CONCLUSIONS AND SIGNIFICANCE: Within the range of sizes tested, prosthesis head size had little impact on vibration transmission to the stapes footplate.

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