Laser interferometric measurements of basilar membrane vibrations in cats using a round window approach

Abstract Objective This paper describes the construction of portals for electrode placement during cochlear implantation and emphasises the utility of pre-operative temporal bone three-dimensional computed tomography. Methods Temporal bone three-dimensional computed tomography was used to plan portal creation for electrode insertion. Results Pre-operative temporal bone three-dimensional computed tomography can be used to determine the orientation of temporal bone structures, which is important for mastoidectomy, posterior tympanotomy and cochleostomy, and when using the round window approach. Conclusion It is essential to create appropriate portals (from the mastoid cortex to the cochlea) in a step-by-step manner, to ensure the safe insertion of electrodes into the scala tympani. Pre-operative three-dimensional temporal bone computed tomography is invaluable in this respect.

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Finite Element Model of Human Cochlea Considering of the Helicotrema Size

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.456.576 ◽

2013 ◽

Vol 456 ◽

pp. 576-581 ◽

Cited By ~ 1

Author(s):

Li Fu Xu ◽

Na Ta ◽

Zhu Shi Rao ◽

Jia Bin Tian

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Basilar Membrane ◽

Round Window ◽

Element Model ◽

Oval Window ◽

Fe Model ◽

Cochlear Duct ◽

Human Cochlea ◽

Set Up

A 2-D finite element model of human cochlea is established in this paper. This model includes the structure of oval window, round window, basilar membrane and cochlear duct which is filled with fluid. The basilar membrane responses are calculated with sound input on the oval window membrane. In order to study the effects of helicotrema on basilar membrane response, three different helicotrema dimensions are set up in the FE model. A two-way fluid-structure interaction numerical method is used to compute the responses in the cochlea. The influence of the helicotrema is acquired and the frequency selectivity of the basilar membrane motion along the cochlear duct is predicted. These results agree with the experiments and indicate much better results are obtained with appropriate helicotrema size.

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Radiologic measurement of cochlea and hearing preservation rate using slim straight electrode (CI422) and round window approach

Acta Otorhinolaryngologica Italica ◽

10.14639/0392-100x-1579 ◽

2018 ◽

Vol 38 (5) ◽

pp. 468-475

Author(s):

H. Skarzynski ◽

M. Matusiak ◽

M. Furmanek ◽

A. Pilka ◽

E. Wlodarczyk ◽

...

Keyword(s):

Round Window ◽

Hearing Preservation ◽

Window Approach ◽

Radiologic Measurement ◽

Preservation Rate

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Electrically evoked reticular lamina and basilar membrane vibrations in mice with alpha tectorin C1509G mutation

10.1063/1.4939395 ◽

2015 ◽

Author(s):

Tianying Ren ◽

Wenxuan He

Keyword(s):

Basilar Membrane ◽

Membrane Vibrations

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Vestibular Preservation After Cochlear Implantation Using the Round Window Approach

Frontiers in Neurology ◽

10.3389/fneur.2021.656592 ◽

2021 ◽

Vol 12 ◽

Author(s):

Keita Tsukada ◽

Shin-ichi Usami

Keyword(s):

Cochlear Implantation ◽

Round Window ◽

Surgical Techniques ◽

Vestibular Function ◽

Vestibular Evoked Myogenic Potential ◽

Flexible Electrodes ◽

Caloric Testing ◽

Before And After ◽

Window Approach ◽

Caloric Response

Background: The development of less traumatic surgical techniques, such as the round window approach (RWA), as well as the use of flexible electrodes and post-operative steroid administration have enabled the preservation of residual hearing after cochlear implantation (CI) surgery. However, consideration must still be given to the complications that can accompany CI. One such potential complication is the impairment of vestibular function with resulting vertigo symptoms. The aim of our current study was to examine the changes in vestibular function after implantation in patients who received CI using less traumatic surgery, particularly the RWA technique.Methods: Sixty-six patients who received CI in our center were examined by caloric testing, cervical vestibular evoked myogenic potential (cVEMP) and ocular VEMP (oVEMP) before or after implantation, or both, to obtain data on semicircular canal, saccular and utricular function, respectively. Less traumatic CI surgery was performed by the use of the RWA and insertion of flexible electrodes such as MED-EL FLEX soft, FLEX 28, and FLEX 24 (Innsbruck, Austria).Results: Caloric response and the asymmetry ratio of cVEMP and oVEMP were examined before and after implantation using less traumatic surgical techniques. Compared with before implantation, 93.9, 82.4, and 92.5% of the patients showed preserved vestibular function after implantation based on caloric testing, cVEMP and oVEMP results, respectively. We also examined the results for vestibular function by a comparison of the 66 patients using the RWA and flexible electrodes, and 17 patients who underwent cochleostomy and insertion of conventional or hard electrodes. We measured responses using caloric testing, cVEMP and oVEMP in patients after CI. There were no differences in the frequencies of abnormal caloric and oVEMP results in the implanted ears between the RWA and cochleostomy. On the other hand, the frequency of abnormal cVEMP responses in the implanted ears in the patients who received implantation by cochleostomy was significantly higher than that in the patients undergoing surgery using the RWA.Conclusion: Patients receiving CI using less traumatic surgical techniques such as RWA and flexible electrodes have reduced risk of damage to vestibular function.

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