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Gargula S, Ebode D, Maniaci A, Radulesco T, Iannella G, Haddad R, Michel J. Can numerical modeling help us understanding hydrops in Menière's disease? A PRISMA scoping review. J Vestib Res 2025:9574271251335956. [PMID: 40233420 DOI: 10.1177/09574271251335956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2025]
Abstract
BackgroundThe pathophysiology of Meniere's disease (MD) is complex and intertwined with endolymphatic hydrops. Available experimental models have limitations.ObjectiveThis study aimed to analyze the impact of endolymphatic hydrops on cochleovestibular hydrodynamics through numerical simulations.MethodsA comprehensive literature review was conducted following PRISMA guidelines for Scoping Reviews. Articles were sourced in June 2024 from PubMed and Google Scholar using a combination of MESH terms related to hydrodynamics, numerical simulation, and MD. Studies involving numerical simulations of hydrops in the vestibule, cochlea, or both were included.ResultsEight studies on hydrodynamics in hydrops using numerical simulations were included. In cochlear models, hydrops affect basilar membrane mechanics, causing low-frequency hearing loss, auditory distortions, and frequency shifts. Vestibular models revealed increased static pressure in the horizontal semicircular canal, explaining abnormal vHIT findings in hydrops patients. Models also suggested chaotic fluid dynamics in dilated labyrinthine structures during caloric tests. The reviewed studies underscore the utility of numerical models in understanding the mechanics of MD; however, significant limitations were identified.ConclusionsNumerical modeling offers valuable insights into the hydrodynamic changes caused by endolymphatic hydrops in MD, but future work should address the current limitations by incorporating more accurate anatomical features and chronic progression in simulations.
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Affiliation(s)
- Stéphane Gargula
- ENT-HNS Department, Aix Marseille University, APHM, CNRS, IUSTI, La Conception University Hospital, Marseille, France
| | - Dario Ebode
- ENT-HNS Department, Aix Marseille University, APHM, CNRS, IUSTI, La Conception University Hospital, Marseille, France
| | - Antonino Maniaci
- Department of "Organi Di Senso," University "Sapienza", Rome, Italy
| | - Thomas Radulesco
- ENT-HNS Department, Aix Marseille University, APHM, CNRS, IUSTI, La Conception University Hospital, Marseille, France
| | | | | | - Justin Michel
- ENT-HNS Department, Aix Marseille University, APHM, CNRS, IUSTI, La Conception University Hospital, Marseille, France
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Matson C, Castle N, Dai C. Developing a Virtual Model of the Rhesus Macaque Inner Ear. Bioengineering (Basel) 2024; 11:1158. [PMID: 39593818 PMCID: PMC11592339 DOI: 10.3390/bioengineering11111158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2024] [Revised: 11/02/2024] [Accepted: 11/06/2024] [Indexed: 11/28/2024] Open
Abstract
A virtual model of the rhesus macaque inner ear was created in the present study. Rhesus macaques have been valuable in cochlear research; however, their high cost prompts a need for alternative methods. Finite Element (FE) analysis offers a promising solution by enabling detailed simulations of the inner ear. This study employs FE analysis to create a virtual model of the rhesus macaque's inner ear, reconstructed from MRI scans, to explore how cochlear implants (CIs) impact residual hearing loss. Harmonic-acoustic simulations of sound wave transmission indicate that CIs have minor effects on the displacement of the basilar membrane and thus minimally impact residual hearing loss post-implantation, but stiffening of the round window membrane worsens this effect. While the rhesus macaque FE model presented in this study shows some promise, its potential applications will require further validation through additional simulations and experimental studies.
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Affiliation(s)
- Cayman Matson
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA;
| | - Nicholas Castle
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA;
- Biomedical Engineering Department, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Chenkai Dai
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA;
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA;
- Biomedical Engineering Department, Johns Hopkins University, Baltimore, MD 21218, USA
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Chen J, Sprigg J, Castle N, Matson C, Hedjoudje A, Dai C. A Virtual Inner Ear Model Selects Ramped Pulse Shapes for Vestibular Afferent Stimulation. Bioengineering (Basel) 2023; 10:1436. [PMID: 38136027 PMCID: PMC10740892 DOI: 10.3390/bioengineering10121436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/03/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Bilateral vestibular deficiency (BVD) results in chronic dizziness, blurry vision when moving the head, and postural instability. Vestibular prostheses (VPs) show promise as a treatment, but the VP-restored vestibulo-ocular reflex (VOR) gain in human trials falls short of expectations. We hypothesize that the slope of the rising ramp in stimulation pulses plays an important role in the recruitment of vestibular afferent units. To test this hypothesis, we utilized customized programming to generate ramped pulses with different slopes, testing their efficacy in inducing electrically evoked compound action potentials (eCAPs) and current spread via bench tests and simulations in a virtual inner model created in this study. The results confirmed that the slope of the ramping pulses influenced the recruitment of vestibular afferent units. Subsequently, an optimized stimulation pulse train was identified using model simulations, exhibiting improved modulation of vestibular afferent activity. This optimized slope not only reduced the excitation spread within the semicircular canals (SCCs) but also expanded the neural dynamic range. While the model simulations exhibited promising results, in vitro and in vivo experiments are warranted to validate the findings of this study in future investigations.
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Affiliation(s)
- Joseph Chen
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
- School of Medicine and Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Jayden Sprigg
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Nicholas Castle
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Cayman Matson
- School of Medicine and Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | | | - Chenkai Dai
- Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
- School of Medicine and Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA
- Biomedical Engineering Department, Johns Hopkins University, Baltimore, MD 21218, USA
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Castle N, Liang J, Smith M, Petersen B, Matson C, Eldridge T, Zhang K, Lee CH, Liu Y, Dai C. Finite Element Modeling of Residual Hearing after Cochlear Implant Surgery in Chinchillas. Bioengineering (Basel) 2023; 10:bioengineering10050539. [PMID: 37237608 DOI: 10.3390/bioengineering10050539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/28/2023] Open
Abstract
Cochlear implant (CI) surgery is one of the most utilized treatments for severe hearing loss. However, the effects of a successful scala tympani insertion on the mechanics of hearing are not yet fully understood. This paper presents a finite element (FE) model of the chinchilla inner ear for studying the interrelationship between the mechanical function and the insertion angle of a CI electrode. This FE model includes a three-chambered cochlea and full vestibular system, accomplished using µ-MRI and µ-CT scanning technologies. This model's first application found minimal loss of residual hearing due to insertion angle after CI surgery, and this indicates that it is a reliable and helpful tool for future applications in CI design, surgical planning, and stimuli setup.
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Affiliation(s)
- Nicholas Castle
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Junfeng Liang
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Matthew Smith
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Brett Petersen
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Cayman Matson
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Tara Eldridge
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Ke Zhang
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Chung-Hao Lee
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Yingtao Liu
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Chenkai Dai
- Department of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA
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