Low-Frequency Sound Pressure and Transtympanic Endoscopy of the Middle Ear in Assessment of “Spontaneous” Perilymphatic Fistula

This study was designed to verify an eventual perilymphatic fistula (PLF) in 264 patients with sensorineural hearing loss (SNHL) and/or vertigo. The patients were exposed to a low-frequency sound stimulation (LFS) on posturography to objectively test Tullio’s phenomenon and Hennebert's sign. Endoscopes with 5 degree and 25 degree of visual angle and an outer diameter of 1.7 mm were used. The round window niche, with its foldings, oval window with stapes superstructure, a part of the facial recess and the area in the fissula ante fenestram were examined and video recorded. In one patient, we endoscopically verified a fistula in the round window membrane (resulting from a diving accident) that was covered with a fibrinous layer. In 4 cases, there was abnormal mucosal shining in the round window but without PLF. In 7 cases, the tympanic cavity could not be visualized because of the adhesive middle ear process, the abnormal anatomy, or the prominent exostoses of the ear canal prohibited vision. In 34 patients, LFS provoked unsteadiness on posturography without PLF. In 6 cases, a postoperative middle ear infection was recorded. No permanent tympanic membrane perforation occurred. It is unlikely that disease entity of “spontaneous PLF” exists. Tympanoscopy should be regarded as the first choice when a PLF is suspected.

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Can low frequency sound stimulation during posturography help diagnosing possible perilymphatic fistula in patients with sensorineural hearing loss and/or vertigo?

European Archives of Oto-Rhino-Laryngology ◽

10.1007/s00405-003-0614-y ◽

2004 ◽

Vol 261 (3) ◽

pp. 129-132 ◽

Cited By ~ 1

Author(s):

Z. Selmani ◽

H. Ishizaki ◽

I. Pyykk�

Keyword(s):

Hearing Loss ◽

Sensorineural Hearing Loss ◽

Low Frequency ◽

Sensorineural Hearing ◽

Sound Stimulation ◽

Perilymphatic Fistula ◽

Frequency Sound

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Rupture of the round Window Membrane

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947608500119 ◽

1976 ◽

Vol 85 (1) ◽

pp. 105-110 ◽

Cited By ~ 9

Author(s):

P. H. Taylor ◽

P. G. Bicknell

Keyword(s):

Middle Ear ◽

Surgical Intervention ◽

Round Window ◽

Oval Window ◽

Round Window Membrane ◽

Physical Effort ◽

Cochlear Aqueduct ◽

Definite Improvement ◽

History Of ◽

Pressure Changes

A case of sudden deafness due to rupture of the round window membrane is presented. Nineteen similar cases have previously been reported in the literature. In a review of these twenty patients, it is noted that a history of concurrent physical effort or barotrauma was present in eighteen. This supports the view that the injury is produced by pressure changes acting either along the cochlear aqueduct (the explosive route) or, directly on the middle ear structures (the implosive route). At operation, the rupture may be difficult to see, and a separate leak from the oval window may be present. The timing of any surgical intervention is important. The authors recommend that this should be deferred for one week after the onset of symptoms, as the fistula may heal spontaneously. If no definite improvement has occurred at the end of this time, then tympanotomy should be undertaken during the next week.

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FINITE ELEMENT ANALYSIS OF THE EFFECT OF ACTUATOR COUPLING CONDITIONS ON ROUND WINDOW STIMULATION

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519415500487 ◽

2015 ◽

Vol 15 (04) ◽

pp. 1550048 ◽

Cited By ~ 7

Author(s):

JIABIN TIAN ◽

XINSHENG HUANG ◽

ZHUSHI RAO ◽

NA TA ◽

LIFU XU

Keyword(s):

Finite Element ◽

Middle Ear ◽

Round Window ◽

Round Window Membrane ◽

Fe Model ◽

Ear Canal ◽

Sound Stimulation ◽

Fe Method ◽

Coupling Conditions ◽

Intracochlear Pressure

The finite element (FE) method was used to analyze the effect of coupling conditions between the actuator and the round window membrane (RWM) on the performance of round window (RW) stimulation. A FE model of the human ear consisting of the external ear canal, middle ear and cochlea was firstly developed, and then validation of this model was accomplished through comparison between analytical results and experimental data in the literature. Intracochlear pressure were derived from the model under normal forward sound stimulation and reverse RW stimulation. The equivalent sound pressure of RW stimulation was then calculated via comparing the differential intracochlear pressure produced by the actuator and normal ear canal sound stimulus. The actuator was simulated as a floating mass and placed onto the middle ear cavity side of RWM. Two aspects about the actuator coupling conditions were considered in this study: (1) the cross-section area of the actuator relative to the RWM; (2) the coupling layer between the actuator and the RWM. The results show that smaller actuator size can improve the implant performance of RW stimulation, and size requirements of the actuator can also be reduced by introducing a coupling layer between the actuator and RWM, which will benefit the manufacture of the actuator.

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Role of the Round Window Membrane in Middle Ear Immune Responses

Acta Oto-Laryngologica ◽

10.3109/00016488809138897 ◽

1988 ◽

Vol 105 (sup457) ◽

pp. 139-143 ◽

Cited By ~ 3

Author(s):

E. M. Keithley ◽

A. F. Ryan ◽

J. P. Harris

Keyword(s):

Immune Responses ◽

Middle Ear ◽

Round Window ◽

Round Window Membrane

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Round window application of an active middle ear implant (AMEI) system in congenital oval window atresia

Acta Oto-Laryngologica ◽

10.3109/00016489.2014.1003091 ◽

2015 ◽

Vol 136 (1) ◽

pp. 23-33 ◽

Cited By ~ 10

Author(s):

Shouqin Zhao ◽

Shusheng Gong ◽

Demin Han ◽

Hua Zhang ◽

Xiaobo Ma ◽

...

Keyword(s):

Middle Ear ◽

Round Window ◽

Oval Window ◽

Active Middle Ear Implant ◽

Middle Ear Implant

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Influence of ossicular chain malformation on the performance of round-window stimulation: A finite element approach

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411919839911 ◽

2019 ◽

Vol 233 (5) ◽

pp. 584-594 ◽

Cited By ~ 5

Author(s):

Houguang Liu ◽

Hu Zhang ◽

Jianhua Yang ◽

Xinsheng Huang ◽

Wen Liu ◽

...

Keyword(s):

Finite Element ◽

Middle Ear ◽

Basilar Membrane ◽

Round Window ◽

Low Frequency ◽

Element Model ◽

Ossicular Chain ◽

Asymmetric Structure ◽

Low Frequencies ◽

Stapes Fixation

As a novel application of implantable middle ear hearing device, round-window stimulation is widely used to treat hearing loss with middle ear disease, such as ossicular chain malformation. To evaluate the influence of ossicular chain malformations on the efficiency of the round-window stimulation, a human ear finite element model, which incorporates cochlear asymmetric structure, was constructed. Five groups of comparison with experimental data confirmed the model’s validity. Based on this model, we investigated the influence of three categories of ossicular chain malformations, that is, incudostapedial disconnection, incus and malleus fixation, and fixation of the stapes. These malformations’ effects were evaluated by comparing the equivalent sound pressures derived from the basilar membrane displacement. Results show that the studied ossicular chain malformations mainly affected the round-window simulation’s performance at low frequencies. In contrast to the fixation of the ossicles, which mainly deteriorates round-window simulation’s low-frequency performance, incudostapedial disconnection increases this performance, especially in the absence of incus process and stapes superstructure. Among the studied ossicular chain malformations, the stapes fixation has a much more severe impact on the round-window stimulation’s efficiency. Thus, the influence of the patients’ ossicular chain malformations should be considered in the design of the round-window stimulation’s actuator. The low-frequency output of the round-window simulation’s actuator should be enhanced, especially for treating the patients with stapes fixation.

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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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Vestibular Pathophysiologic Changes in Experimental Perilymphatic Fistula

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949210100713 ◽

1992 ◽

Vol 101 (7) ◽

pp. 612-616 ◽

Cited By ~ 11

Author(s):

Yasuya Nomura ◽

Yi-Ho Young ◽

Makoto Hara

Keyword(s):

Round Window ◽

Vestibular Function ◽

Acute Stage ◽

Spontaneous Nystagmus ◽

Round Window Membrane ◽

Caloric Test ◽

Positional Nystagmus ◽

Perilymphatic Fistula ◽

Membrane Changes ◽

Ice Water

An animal model of experimental perilymphatic fistula (EPLF) was developed in the guinea pig in order to study vestibular pathophysiology. In experimental animals, 4 μL of perilymph was suctioned from one cochlea via the round window membrane. Changes in vestibular function were as follows. 1) During the acute stage (5 hours postoperatively), spontaneous nystagmus directed toward the normal side was noted in 57.4% of the EPLF animals. This lasted less than 24 hours. 2) One week postoperatively, direction-fixed positional nystagmus toward the lesioned ear was present in 22.7% of the EPLF animals, especially when the lesioned ear was positioned inferiorly. 3) With the ice water caloric test, no response was present in 58.1% of the EPLF animals and an irregular response was found in 22.6% of them, 1 week postoperatively. These results tend to indicate that tests of vestibular function may differentiate between patients with Meniere's disease and those with perilymphatic fistula. Histologic findings indicate that a floating labyrinth is the cause of positional nystagmus and caloric irregularity. The absence of caloric responses was associated with collapse of the vestibular labyrinth.

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