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Truong DQ, Thomas C, Ira S, Valter Y, Clark TK, Datta A. Unpacking Galvanic Vestibular Stimulation using simulations and relating current flow to reported motions: Comparison across common and specialized electrode placements. PLoS One 2024; 19:e0309007. [PMID: 39186497 PMCID: PMC11346646 DOI: 10.1371/journal.pone.0309007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 08/04/2024] [Indexed: 08/28/2024] Open
Abstract
BACKGROUND Galvanic Vestibular Stimulation (GVS) is a non-invasive electrical stimulation technique that is typically used to probe the vestibular system. When using direct current or very low frequency sine, GVS causes postural sway or perception of illusory (virtual) motions. GVS is commonly delivered using two electrodes placed at the mastoids, however, placements involving additional electrodes / locations have been employed. Our objective was to systematically evaluate all known GVS electrode placements, compare induced current flow, and how it relates to the archetypal sway and virtual motions. The ultimate goal is to help users in having a better understanding of the effects of different placements. METHODS We simulated seven GVS electrode placements with same total injected current using an ultra-high resolution model. Induced electric field (EF) patterns at the cortical and the level of vestibular organs (left and right) were determined. A range of current flow metrics including potential factors such as inter-electrode separation, percentage of current entering the cranial cavity, and symmetricity were calculated. Finally, we relate current flow to reported GVS motions. RESULTS As expected, current flow patterns are electrode placement specific. Placements with two electrodes generally result in higher EF magnitude. Placements with four electrodes result in lower percentage of current entering the cranial cavity. Symmetric placements do not result in similar EF values in the left and the right organs respectively- highlighting inherent anatomical asymmetry of the human head. Asymmetric placements were found to induce as much as ~3-fold higher EF in one organ over the other. The percentage of current entering the cranial cavity varies between ~15% and ~40% depending on the placement. CONCLUSIONS We expect our study to advance understanding of GVS and provide insight on probable mechanism of action of a certain electrode placement choice. The dataset generated across several metrics will support hypothesis testing relating empirical outcomes to current flow patterns. Further, the differences in current flow will guide stimulation strategy (what placement and how much scalp current to use) and facilitate a quantitatively informed rational / optimal decision.
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Affiliation(s)
- Dennis Q. Truong
- Research and Development, Soterix Medical, Woodbridge, New Jersey, United States of America
| | - Chris Thomas
- Research and Development, Soterix Medical, Woodbridge, New Jersey, United States of America
| | - Sanjidah Ira
- Research and Development, Soterix Medical, Woodbridge, New Jersey, United States of America
| | - Yishai Valter
- Research and Development, Soterix Medical, Woodbridge, New Jersey, United States of America
| | - Torin K. Clark
- Smead Aerospace Engineering Sciences Department, College of Engineering and Applied Science, University of Colorado, Boulder, Colorado, United States of America
| | - Abhishek Datta
- Research and Development, Soterix Medical, Woodbridge, New Jersey, United States of America
- Biomedical Engineering, City College of New York, New York, New York, United States of America
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Loos E, Stultiens JJA, Volpe B, Vermorken BL, Van Boxel SCJ, Devocht EMJ, van Hoof M, Postma AA, Guinand N, Pérez-Fornos A, Van Rompaey V, Denys S, Desloovere C, Verhaert N, van de Berg R. Optimizing vestibular implant electrode positioning using fluoroscopy and intraoperative CT imaging. Eur Arch Otorhinolaryngol 2024; 281:3433-3441. [PMID: 38180608 PMCID: PMC11211140 DOI: 10.1007/s00405-023-08428-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 12/18/2023] [Indexed: 01/06/2024]
Abstract
PURPOSE Vestibular implant electrode positioning close to the afferent nerve fibers is considered to be key for effective and selective electrical stimulation. However, accurate positioning of vestibular implant electrodes inside the semicircular canal ampullae is challenging due to the inability to visualize the target during the surgical procedure. This study investigates the accuracy of a new surgical protocol with real-time fluoroscopy and intraoperative CT imaging, which facilitates electrode positioning during vestibular implant surgery. METHODS Single-center case-controlled cohort study with a historic control group at a tertiary referral center. Patients were implanted with a vestibulocochlear implant, using a combination of intraoperative fluoroscopy and cone beam CT imaging. The control group consisted of five patients who were previously implanted with the former implant prototype, without the use of intraoperative imaging. Electrode positioning was analyzed postoperatively with a high-resolution CT scan using 3D slicer software. The result was defined as accurate if the electrode position was within 1.5 mm of the center of the ampulla. RESULTS With the new imaging protocol, all electrodes could be positioned within a 1.5 mm range of the center of the ampulla. The accuracy was significantly higher in the study group with intraoperative imaging (21/21 electrodes) compared to the control group without intraoperative imaging (10/15 electrodes), (p = 0.008). CONCLUSION The combined use of intraoperative fluoroscopy and CT imaging during vestibular implantation can improve the accuracy of electrode positioning. This might lead to better vestibular implant performance.
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Affiliation(s)
- Elke Loos
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands.
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospitals Leuven, Leuven, Belgium.
- Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology (ExpORL), KU Leuven, University of Leuven, Herestraat 49, 3000, Leuven, Belgium.
| | - Joost J A Stultiens
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Benjamin Volpe
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Bernd L Vermorken
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Stan C J Van Boxel
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Elke M J Devocht
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Marc van Hoof
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Alinda A Postma
- Department of Radiology and Nuclear Medicine, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Nils Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Angelica Pérez-Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Vincent Van Rompaey
- Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
- Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Sam Denys
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospitals Leuven, Leuven, Belgium
- Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology (ExpORL), KU Leuven, University of Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Christian Desloovere
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospitals Leuven, Leuven, Belgium
- Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology (ExpORL), KU Leuven, University of Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Nicolas Verhaert
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospitals Leuven, Leuven, Belgium
- Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology (ExpORL), KU Leuven, University of Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Raymond van de Berg
- Department of Otorhinolaryngology-Head and Neck Surgery, Faculty of Health Medicine and Life Sciences, School for Mental Health and Neuroscience (MHeNS), Maastricht University Medical Center, Maastricht, The Netherlands
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Mohammed A, Li S, Liu X. Exploring the Potentials of Wearable Technologies in Managing Vestibular Hypofunction. Bioengineering (Basel) 2024; 11:641. [PMID: 39061723 PMCID: PMC11274252 DOI: 10.3390/bioengineering11070641] [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: 05/04/2024] [Revised: 05/26/2024] [Accepted: 05/31/2024] [Indexed: 07/28/2024] Open
Abstract
The vestibular system is dedicated to gaze stabilization, postural balance, and spatial orientation; this makes vestibular function crucial for our ability to interact effectively with our environment. Vestibular hypofunction (VH) progresses over time, and it presents differently in its early and advanced stages. In the initial stages of VH, the effects of VH are mitigated using vestibular rehabilitation therapy (VRT), which can be facilitated with the aid of technology. At more advanced stages of VH, novel techniques that use wearable technologies for sensory augmentation and sensory substitution have been applied to manage VH. Despite this, the potential of assistive technologies for VH management remains underexplored over the past decades. Hence, in this review article, we present the state-of-the-art technologies for facilitating early-stage VRT and for managing advanced-stage VH. Also, challenges and strategies on how these technologies can be improved to enable long-term ambulatory and home use are presented.
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Affiliation(s)
- Ameer Mohammed
- School of Information Science and Technology, Fudan University, Shanghai 200433, China; (A.M.); (S.L.)
- State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China
| | - Shutong Li
- School of Information Science and Technology, Fudan University, Shanghai 200433, China; (A.M.); (S.L.)
- State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China
| | - Xiao Liu
- School of Information Science and Technology, Fudan University, Shanghai 200433, China; (A.M.); (S.L.)
- State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China
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Ayiotis AI, Schoo DP, Fernandez Brillet C, Lane KE, Carey JP, Della Santina CC. Patient-Reported Outcomes After Vestibular Implantation for Bilateral Vestibular Hypofunction. JAMA Otolaryngol Head Neck Surg 2024; 150:240-248. [PMID: 38300591 PMCID: PMC10835607 DOI: 10.1001/jamaoto.2023.4475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 12/02/2023] [Indexed: 02/02/2024]
Abstract
Importance Standard-of-care treatment proves inadequate for many patients with bilateral vestibular hypofunction (BVH). Vestibular implantation is an emerging alternative. Objective To examine patient-reported outcomes from prosthetic vestibular stimulation. Design, Setting, and Participants The Multichannel Vestibular Implant (MVI) Early Feasibility Study is an ongoing prospective, nonrandomized, single-group, single-center cohort study conducted at Johns Hopkins Hospital that has been active since 2016 in which participants serve as their own controls. The study includes adults with severe or profound adult-onset BVH for at least 1 year and inadequate compensation despite standard-of-care treatment. As of March 2023, 12 candidates completed the eligibility screening process. Intervention The MVI system electrically stimulates semicircular canal branches of the vestibular nerve to convey head rotation. Main Outcomes and Measures Patient-reported outcome instruments assessing dizziness (Dizziness Handicap Inventory [DHI]) and vestibular-related disability (Vestibular Disorders-Activities of Daily Living [VADL]). Health-related quality of life (HRQOL) assessed using the Short Form-36 Utility (SF36U) and Health Utilities Index Mark 3 (HUI3), from which quality-adjusted life-years were computed. Results Ten individuals (5 female [50%]; mean [SD] age, 58.5 [5.0] years; range, 51-66 years) underwent unilateral implantation. A control group of 10 trial applicants (5 female [50%]; mean [SD] age, 55.1 [8.5] years; range, 42-73 years) completed 6-month follow-up surveys after the initial application. After 0.5 years of continuous MVI use, a pooled mean (95% CI) of within-participant changes showed improvements in dizziness (DHI, -36; 95% CI, -55 to -18), vestibular disability (VADL, -1.7; 95% CI, -2.6 to -0.7), and HRQOL by SF36U (0.12; 95% CI, 0.07-0.17) but not HUI3 (0.02; 95% CI, -0.22 to 0.27). Improvements exceeded minimally important differences in the direction of benefit (exceeding 18, 0.65, and 0.03, respectively, for DHI, VADL, and SF36U). The control group reported no mean change in dizziness (DHI, -4; 95% CI, -10 to 2), vestibular disability (VADL, 0.1; 95% CI, -0.9 to 1.1) or HRQOL per SF36U (0; 95% CI, -0.06 to 0.05) but an increase in HRQOL per HUI3 (0.10; 95% CI, 0.04-0.16). Lifetime HRQOL gain for MVI users was estimated to be 1.7 quality-adjusted life-years (95% CI, 0.6-2.8) using SF36U and 1.4 (95% CI, -1.2 to 4.0) using HUI3. Conclusions and Relevance This cohort study found that vestibular implant recipients report vestibular symptom improvements not reported by a control group. These patient-reported benefits support the use of vestibular implantation as a treatment for bilateral vestibular hypofunction.
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Affiliation(s)
- Andrianna I. Ayiotis
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Desi P. Schoo
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology, The Ohio State University Wexner Medical Center, Columbus
| | | | - Kelly E. Lane
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - John P. Carey
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Charles C. Della Santina
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Otolaryngology–Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
- Labyrinth Devices, LLC
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Lue PY, Oliver MH, Neeff M, Thorne PR, Suzuki-Kerr H. Sheep as a large animal model for hearing research: comparison to common laboratory animals and humans. Lab Anim Res 2023; 39:31. [PMID: 38012676 PMCID: PMC10680324 DOI: 10.1186/s42826-023-00182-3] [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: 07/25/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 11/29/2023] Open
Abstract
Sensorineural hearing loss (SNHL), caused by pathology in the cochlea, is the most common type of hearing loss in humans. It is generally irreversible with very few effective pharmacological treatments available to prevent the degenerative changes or minimise the impact. Part of this has been attributed to difficulty of translating "proof-of-concept" for novel treatments established in small animal models to human therapies. There is an increasing interest in the use of sheep as a large animal model. In this article, we review the small and large animal models used in pre-clinical hearing research such as mice, rats, chinchilla, guinea pig, rabbit, cat, monkey, dog, pig, and sheep to humans, and compare the physiology, inner ear anatomy, and some of their use as model systems for SNHL, including cochlear implantation surgeries. Sheep have similar cochlear anatomy, auditory threshold, neonatal auditory system development, adult and infant body size, and number of birth as humans. Based on these comparisons, we suggest that sheep are well-suited as a potential translational animal model that bridges the gap between rodent model research to the clinical use in humans. This is especially in areas looking at changes across the life-course or in specific areas of experimental investigation such as cochlear implantation and other surgical procedures, biomedical device development and age-related sensorineural hearing loss research. Combined use of small animals for research that require higher throughput and genetic modification and large animals for medical translation could greatly accelerate the overall translation of basic research in the field of auditory neuroscience from bench to clinic.
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Affiliation(s)
- Po-Yi Lue
- Department of Physiology, The University of Auckland, Auckland, New Zealand
- Eisdell Moore Centre, The University of Auckland, Auckland, New Zealand
| | - Mark H Oliver
- Liggins Institute, The University of Auckland, Auckland, New Zealand
- Ngapouri Research Farm Laboratory, University of Auckland, Waiotapu, New Zealand
| | - Michel Neeff
- Department of Physiology, The University of Auckland, Auckland, New Zealand
- Department of Surgery, Auckland District Health Board, Auckland, New Zealand
| | - Peter R Thorne
- Department of Physiology, The University of Auckland, Auckland, New Zealand
- Eisdell Moore Centre, The University of Auckland, Auckland, New Zealand
- Section of Audiology, The University of Auckland, Auckland, New Zealand
| | - Haruna Suzuki-Kerr
- Department of Physiology, The University of Auckland, Auckland, New Zealand.
- Eisdell Moore Centre, The University of Auckland, Auckland, New Zealand.
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韩 鹏, 赵 欢, 张 令, 陈 耔, 张 玉, 张 甦, 任 鹏, 张 青. [Recent progress in vestibular prosthesis]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2023; 37:848-852. [PMID: 37828894 PMCID: PMC10803241 DOI: 10.13201/j.issn.2096-7993.2023.10.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Indexed: 10/14/2023]
Abstract
Bilateral vestibulopathy(BVP) is one of the common diseases in the vestibular nervous system, with an incidence rate of about 4%-7% in the population, which can lead to a variety of body dysfunctions. At present, there are two main treatment methods for BVP. One is vestibular rehabilitation. However, only part of BVP patients can finally benefit from vestibular rehabilitation, and most patients will remain with permanent vestibular dysfunction. Benefiting from the maturity of cochlear implant technology, European and American countries took the lead in the development of vestibular prosthesis(VP) technology to restore the vestibular function in patients with BVP. This review will focus on the development history, principles, future applications and the related research progress of VP in China.
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Affiliation(s)
- 鹏 韩
- 西安交通大学第一附属医院耳鼻咽喉头颈外科(西安,710061)Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, 710061, China
| | - 欢娣 赵
- 西安交通大学第二附属医院耳鼻咽喉头颈外科Department of Otorhinolaryngology Head and Neck Surgery, Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an
| | - 令 张
- 西安交通大学第一附属医院耳鼻咽喉头颈外科(西安,710061)Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, 710061, China
| | - 耔辰 陈
- 西安交通大学第二附属医院耳鼻咽喉头颈外科Department of Otorhinolaryngology Head and Neck Surgery, Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an
| | - 玉忠 张
- 西安交通大学第二附属医院耳鼻咽喉头颈外科Department of Otorhinolaryngology Head and Neck Surgery, Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an
| | - 甦琳 张
- 华中科技大学同济医学院附属协和医院耳鼻咽喉科Department of Otorhinolaryngology Head and Neck Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology
| | - 鹏宇 任
- 西安交通大学第二附属医院神经外科Department of Neurosurgery, Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine
| | - 青 张
- 上海交通大学附属新华医院耳鼻咽喉头颈外科Department of Otorhinolaryngology Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine
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Soto E, Pliego A, Vega R. Vestibular prosthesis: from basic research to clinics. Front Integr Neurosci 2023; 17:1161860. [PMID: 37265514 PMCID: PMC10230114 DOI: 10.3389/fnint.2023.1161860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/26/2023] [Indexed: 06/03/2023] Open
Abstract
Balance disorders are highly prevalent worldwide, causing substantial disability with high personal and socioeconomic impact. The prognosis in many of these patients is poor, and rehabilitation programs provide little help in many cases. This medical problem can be addressed using microelectronics by combining the highly successful cochlear implant experience to produce a vestibular prosthesis, using the technical advances in micro gyroscopes and micro accelerometers, which are the electronic equivalents of the semicircular canals (SCC) and the otolithic organs. Reaching this technological milestone fostered the possibility of using these electronic devices to substitute the vestibular function, mainly for visual stability and posture, in case of damage to the vestibular endorgans. The development of implantable and non-implantable devices showed diverse outcomes when considering the integrity of the vestibular pathways, the device parameters (current intensity, impedance, and waveform), and the targeted physiological function (balance and gaze). In this review, we will examine the development and testing of various prototypes of the vestibular implant (VI). The insight raised by examining the state-of-the-art vestibular prosthesis will facilitate the development of new device-development strategies and discuss the feasibility of complex combinations of implantable devices for disorders that directly affect balance and motor performance.
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Affiliation(s)
- Enrique Soto
- Benemérita Universidad Autónoma de Puebla, Instituto de Fisiología, Puebla, Mexico
| | - Adriana Pliego
- Benemérita Universidad Autónoma de Puebla, Instituto de Fisiología, Puebla, Mexico
- Universidad Autónoma del Estado de México (UAEMéx), Facultad de Medicina, Toluca, Mexico
| | - Rosario Vega
- Benemérita Universidad Autónoma de Puebla, Instituto de Fisiología, Puebla, Mexico
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Chow MR, Fernandez Brillet C, Hageman KN, Roberts DC, Ayiotis AI, Haque RM, Della Santina CC. Binocular 3-D otolith-ocular reflexes: responses of chinchillas to natural and prosthetic stimulation after ototoxic injury and vestibular implantation. J Neurophysiol 2023; 129:1157-1176. [PMID: 37018758 PMCID: PMC10151050 DOI: 10.1152/jn.00445.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/29/2023] [Accepted: 03/29/2023] [Indexed: 04/07/2023] Open
Abstract
The otolith end organs inform the brain about gravitational and linear accelerations, driving the otolith-ocular reflex (OOR) to stabilize the eyes during translational motion (e.g., moving forward without rotating) and head tilt with respect to gravity. We previously characterized OOR responses of normal chinchillas to whole body tilt and translation and to prosthetic electrical stimulation targeting the utricle and saccule via electrodes implanted in otherwise normal ears. Here we extend that work to examine OOR responses to tilt and translation stimuli after unilateral intratympanic gentamicin injection and to natural/mechanical and prosthetic/electrical stimulation delivered separately or in combination to animals with bilateral vestibular hypofunction after right ear intratympanic gentamicin injection followed by surgical disruption of the left labyrinth at the time of electrode implantation. Unilateral intratympanic gentamicin injection decreased natural OOR response magnitude to about half of normal, without markedly changing OOR response direction or symmetry. Subsequent surgical disruption of the contralateral labyrinth at the time of electrode implantation surgery further decreased OOR magnitude during natural stimulation, consistent with bimodal-bilateral otolith end organ hypofunction (ototoxic on the right ear, surgical on the left ear). Delivery of pulse frequency- or pulse amplitude-modulated prosthetic/electrical stimulation targeting the left utricle and saccule in phase with whole body tilt and translation motion stimuli yielded responses closer to normal than the deficient OOR responses of those same animals in response to head tilt and translation alone.NEW & NOTEWORTHY Previous studies to expand the scope of prosthetic stimulation of the otolith end organs showed that selective stimulation of the utricle and saccule is possible. This article further defines those possibilities by characterizing a diseased animal model and subsequently studying its responses to electrical stimulation alone and in combination with mechanical motion. We show that we can partially restore responses to tilt and translation in animals with unilateral gentamicin ototoxic injury and contralateral surgical disruption.
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Affiliation(s)
- Margaret R Chow
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Celia Fernandez Brillet
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Kristin N Hageman
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Dale C Roberts
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Andrianna I Ayiotis
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
| | - Razi M Haque
- Lawrence Livermore National Laboratory, Livermore, California, United States
| | - Charles C Della Santina
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
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Accelerated Cognitive Decline Associated With Hearing Loss and Bilateral Vestibulopathy: Insights From a Prospective Cross-Sectional Study Using the Repeatable Battery for the Assessment of Neuropsychological Status Adjusted for the Hearing Impaired in the DFNA9 Population. Ear Hear 2022:00003446-990000000-00090. [PMID: 36607747 PMCID: PMC10262994 DOI: 10.1097/aud.0000000000001315] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND DeaFNess Autosomal dominant 9 (DFNA9) is a hereditary disorder known to affect both hearing and vestibular function in its carriers. Its phenotype is characterized by progressive sensorineural hearing loss (SNHL) and vestibular dysfunction evolving towards bilateral vestibulopathy (BV) by the 3rd to 5th life decade. Recent studies have identified the impact of hearing loss and vestibular dysfunction on cognitive functioning. OBJECTIVE The main objective of this study was to investigate how the cognitive functioning of carriers of the p.Pro51Ser variant in the COCH gene is affected by the disease and compare these results with a matched healthy control group. STUDY DESIGN Forty-six carriers of the pathogenic p.Pro51Ser variant in the COCH gene were included in this study, of which 38 met the Bárány Society criteria and were thus diagnosed with BV. All subjects were between the age of 22 and 72 years old. Each control was individually matched based on age, gender, and education level. A cognitive, vestibular, and hearing assessment was performed in all subjects. All participants completed the Repeatable Battery for the Assessment of Neuropsychological Status, adjusted for the Hearing Impaired (RBANS-H), a cognitive test battery that includes subtests probing Immediate and Delayed Memory, Visuospatial/Constructional, Language, and Attention. RESULTS Overall, the DFNA9 patients demonstrated significantly lower scores on the Immediate Memory subscale and lower Total Scale scores than their healthy matched controls. The total sample was divided into two groups: age <55 years old and age ≥55 years old. The DFNA9 group aged ≥55 years old obtained significantly lower scores on the Attention subscale and lower Total Scale scores than their matched controls. Cognition of DFNA9 patients aged <55 years old no longer differed significantly from their matched controls. CONCLUSION This cross-sectional study found that DFNA9 patients demonstrated cognitive deficits in comparison with their healthy matched controls. The DFNA9 group aged ≥ 55 years old obtained significantly lower scores on the Total Scale and Attention subscale. This finding; however, was not observed for the age group younger than 55 years old. Further research is needed on the individual trajectory of SNHL and vestibular function, and how hearing rehabilitation affects cognitive functioning.
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Starkov D, Pleshkov M, Guinand N, Pérez Fornos A, Ranieri M, Cavuscens S, Stultiens JJA, Devocht EMJ, Kingma H, van de Berg R. Optimized Signal Analysis to Quantify the Non-Linear Behaviour of the Electrically Evoked Vestibulo-Ocular Reflex in Patients with a Vestibular Implant. Audiol Neurootol 2022; 27:458-468. [PMID: 35817001 PMCID: PMC9808707 DOI: 10.1159/000525577] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 06/06/2022] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Different eye movement analysis algorithms are used in vestibular implant research to quantify the electrically evoked vestibulo-ocular reflex (eVOR). Often, standard techniques are used as applied for quantification of the natural VOR in healthy subjects and patients with vestibular loss. However, in previous research, it was observed that the morphology of the VOR and eVOR may differ substantially. In this study, it was investigated if the analysis techniques for eVOR need to be adapted to optimize a truthful quantification of the eVOR (VOR gain, orientation of the VOR axis, asymmetry, and phase shift). METHODS "Natural" VOR responses were obtained in six age-matched healthy subjects, and eVOR responses were obtained in eight bilateral-vestibulopathy patients fitted with a vestibular implant. Three conditions were tested: "nVOR" 1-Hz sinusoidal whole-body rotations of healthy subjects in a rotatory chair, "eVOR" 1-Hz sinusoidal electrical vestibular implant stimulation without whole-body rotations in bilateral-vestibulopathy patients, and "dVOR" 1-Hz sinusoidal whole-body rotations in bilateral-vestibulopathy patients using the chair-mounted gyroscope output to drive the electrical vestibular implant stimulation (therefore also in sync 1 Hz sinusoidal). VOR outcomes were determined from the obtained VOR responses, using three different eye movement analysis paradigms: (1) peak eye velocity detection using the raw eye traces; (2) peak eye velocity detection using full-cycle sine fitting of eye traces; (3) peak eye velocity detection using half-cycle sine fitting of eye traces. RESULTS The type of eye movement analysis algorithm significantly influenced VOR outcomes, especially regarding the VOR gain and asymmetry of the eVOR in bilateral-vestibulopathy patients fitted with a vestibular implant. Full-cycle fitting lowered VOR gain in the eVOR condition (mean difference: 0.14 ± 0.06 95% CI, p = 0.018). Half-cycle fitting lowered VOR gain in the dVOR condition (mean difference: 0.08 ± 0.04 95% CI, p = 0.009). In the eVOR condition, half-cycle fitting was able to demonstrate the asymmetry between the excitatory and inhibitory phases of stimulation in comparison with the full-cycle fitting (mean difference: 0.19 ± 0.12 95% CI, p = 0.024). The VOR axis and phase shift did not differ significantly between eye movement analysis algorithms. In healthy subjects, no clinically significant effect of eye movement analysis algorithms on VOR outcomes was observed. CONCLUSION For the analysis of the eVOR, the excitatory and inhibitory phases of stimulation should be analysed separately due to the inherent asymmetry of the eVOR. A half-cycle fitting method can be used as a more accurate alternative for the analysis of the full-cycle traces.
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Affiliation(s)
- Dmitrii Starkov
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation,*Dmitrii Starkov,
| | - Maksim Pleshkov
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
| | - Nils Guinand
- Department of Clinical Neurosciences, Service of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Angélica Pérez Fornos
- Department of Clinical Neurosciences, Service of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Maurizio Ranieri
- Department of Clinical Neurosciences, Service of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Samuel Cavuscens
- Department of Clinical Neurosciences, Service of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Joost Johannes Antonius Stultiens
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Elke Maria Johanna Devocht
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Herman Kingma
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
| | - Raymond van de Berg
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
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Bosmans J, Gommeren H, Mertens G, Cras P, Engelborghs S, Van Ombergen A, Vereeck L, Gilles A, Van Rompaey V. Associations of Bilateral Vestibulopathy With Cognition in Older Adults Matched With Healthy Controls for Hearing Status. JAMA Otolaryngol Head Neck Surg 2022; 148:731-739. [PMID: 35708675 PMCID: PMC9204614 DOI: 10.1001/jamaoto.2022.1303] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Question Is bilateral vestibulopathy (BV) associated with cognitive function in older adults? Findings In this cross-sectional study including 34 participants with BV and 34 age-, sex-, and hearing performance–matched controls, participants with BV had worse cognitive function in general, which was most pronounced in the subdomains of immediate memory, visuospatial cognition, and attention. Meaning These findings support existing evidence on an association between vestibular loss and cognitive impairment. Importance Recent literature suggests there may be a significant effect of the vestibular system on cognition and visuospatial processing. Given the increasing prevalence of dementia and individuals at risk for it, exploring possible modifiable risk factors, including vestibular dysfunction, is vital. Objectives To explore the association of bilateral vestibulopathy (BV) with cognitive function in older adults, taking hearing status into account, and to explore multiple vestibular characteristics and their potential associations with cognition in patients with BV. Design, Setting, and Participants This cross-sectional study assessed older adults (age 55-84 years) with diagnosed BV from a single center using baseline measurements from the Gehoor, Evenwicht en Cognitie (GECKO) study, an ongoing prospective longitudinal cohort study. Each participant was individually matched with a healthy control based on age, sex, and hearing performance. Data were analyzed in January 2022. Main Outcomes and Measures The primary outcome measure was cognition, measured by the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing-Impaired Individuals (RBANS-H). Results A total of 68 patients were assessed, including 34 patients with BV (mean [SD] age, 63.3 [6.0] years; 18 [53%] men) matched with 34 control individuals without BV. Overall, participants with BV had a clinically meaningful lower score on the RBANS-H total scale compared with those without BV (mean [SD] score, 98.62 [12.70] vs 105.91 [11.03]). This decline was most pronounced in the subdomains of immediate memory (mean [SD] score, 107.74 [10.66] vs 112.26 [10.66]), visuospatial cognition (mean [SD] score, 90.06 [13.34] vs 100.47 [13.91]), and attention (mean [SD] score, 94.79 [16.39] vs 102.06 [12.97]). There were no differences in language or delayed memory subdomains. Within the BV population, 1 vestibular parameter (the Performance-Oriented Mobility Assessment, in particular the balance subscale) was associated with lower cognitive scores (r32 = 0.51; 95% CI, 0.20 to 0.72; η2 = 0.26). Other vestibular parameters, including measurements of the peripheral vestibular end organ and questionnaires, showed no association. Conclusions and Relevance These findings suggest there was an association between vestibular loss and cognitive impairment. Further research on the causal mechanisms underlying this association and the possible impact of vestibular rehabilitation on cognition is needed.
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Affiliation(s)
- Joyce Bosmans
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium
| | - Hanne Gommeren
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium.,University Department of Otorhinolaryngology-Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Griet Mertens
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium.,University Department of Otorhinolaryngology-Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Patrick Cras
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium.,Department of Neurology, Antwerp University Hospital and Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Sebastiaan Engelborghs
- Department of Neurology, Universitair Ziekenhuis Brussel and Center for Neurosciences, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Angelique Van Ombergen
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium
| | - Luc Vereeck
- Department of Rehabilitation Sciences and Physiotherapy, Move Antwerp, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium
| | - Annick Gilles
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium.,University Department of Otorhinolaryngology-Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium.,Department of Education, Health & Social Work, University College Ghent, Ghent, Belgium
| | - Vincent Van Rompaey
- Department of Translational Neurosciences, Faculty of Medicine and Health Science, University of Antwerp, Antwerp, Belgium.,University Department of Otorhinolaryngology-Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
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van Stiphout L, Pleshkov M, Lucieer F, Dobbels B, Mavrodiev V, Guinand N, Pérez Fornos A, Widdershoven J, Strupp M, Van Rompaey V, van de Berg R. Patterns of Vestibular Impairment in Bilateral Vestibulopathy and Its Relation to Etiology. Front Neurol 2022; 13:856472. [PMID: 35386413 PMCID: PMC8979031 DOI: 10.3389/fneur.2022.856472] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/17/2022] [Indexed: 11/23/2022] Open
Abstract
Objective This study aimed to investigate (1) the patterns of vestibular impairment in bilateral vestibulopathy (BVP) and subsequently, the implications regarding patient eligibility for vestibular implantation, and (2) whether this pattern and severity of vestibular impairment is etiology dependent. Methods A total of one hundred and seventy-three subjects from three tertiary referral centers in Europe were diagnosed with BVP according to the Bárány Society diagnostic criteria. The subjects underwent vestibular testing such as the caloric test, torsion swing test, video Head Impulse Test (vHIT) in horizontal and vertical planes, and cervical and/or ocular vestibular evoked myogenic potentials (c- and oVEMPs). The etiologies were split into idiopathic, genetic, ototoxicity, infectious, Menière's Disease, (head)trauma, auto-immune, neurodegenerative, congenital, and mixed etiology. Results The caloric test and horizontal vHIT more often indicated horizontal semicircular canal impairment than the torsion swing test. The vHIT results showed significantly higher gains for both anterior canals compared with the horizontal and posterior canals (p < 0.001). The rates of bilaterally absent oVEMP responses were higher compared to the bilaterally absent cVEMP responses (p = 0.010). A total of fifty-four percent of the patients diagnosed with BVP without missing data met all three Bárány Society diagnostic test criteria, whereas 76% of the patients were eligible for implantation according to the vestibular implantation criteria. Regarding etiology, only horizontal vHIT results were significantly lower for trauma, neurodegenerative, and genetic disorders, whereas the horizontal vHIT results were significantly higher for Menière's Disease, infectious and idiopathic BVP. The exploration with hierarchical cluster analysis showed no significant association between etiology and patterns of vestibular impairment. Conclusion This study showed that caloric testing and vHIT seem to be more sensitive for measuring vestibular impairment, whereas the torsion swing test is more suited for measuring residual vestibular function. In addition, no striking patterns of vestibular impairment in relation to etiology were found. Nevertheless, it was demonstrated that although the implantation criteria are stricter compared with the Bárány Society diagnostic criteria, still, 76% of patients with BVP were eligible for implantation based on the vestibular test criteria. It is advised to carefully examine every patient for their overall pattern of vestibular impairment in order to make well-informed and personalized therapeutic decisions.
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Affiliation(s)
- Lisa van Stiphout
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
- *Correspondence: Lisa van Stiphout
| | - Maksim Pleshkov
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
- Faculty of Physics, Tomsk State University, Tomsk, Russia
- Maksim Pleshkov
| | - Florence Lucieer
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
| | - Bieke Dobbels
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Vergil Mavrodiev
- Department of Neurology and German Center for Vertigo, Ludwig-Maximilians University, Munich, Germany
| | - Nils Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Angelica Pérez Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Josine Widdershoven
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Michael Strupp
- Department of Neurology and German Center for Vertigo, Ludwig-Maximilians University, Munich, Germany
| | - Vincent Van Rompaey
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Raymond van de Berg
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, Netherlands
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van Stiphout L, Hossein I, Kimman M, Whitney SL, Ayiotis A, Strupp M, Guinand N, Pérez Fornos A, Widdershoven J, Ramos-Macías Á, Van Rompaey V, van de Berg R. Development and Content Validity of the Bilateral Vestibulopathy Questionnaire. Front Neurol 2022; 13:852048. [PMID: 35370880 PMCID: PMC8968143 DOI: 10.3389/fneur.2022.852048] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/15/2022] [Indexed: 11/30/2022] Open
Abstract
Background To date, the burden and severity of the full spectrum of bilateral vestibulopathy (BVP) symptoms has not yet been measured in a standardized manner. Since therapeutic interventions aiming to improve BVP symptoms are emerging, the need for a new standardized assessment tool that encompasses the specific aspects of BVP arises. Therefore, the aim of this study was to develop a multi-item Patient Reported Outcome Measure (PROM) that captures the clinically important symptoms of BVP and assesses its impact on daily life. Methods The development of the Bilateral Vestibulopathy Questionnaire (BVQ) consisted of two phases: (I) initial item generation and (II) face and content validity testing. Items were derived from a literature review and individual semi-structured interviews focusing on the full spectrum of reported BVP symptoms (I). Subsequently (IIa), individual patient interviews were conducted using “thinking aloud” and concurrent verbal probing techniques to assess the comprehensibility of the instructions, questions and response options, and the relevance, missing domains, or missing items. Interviews continued until saturation of input was reached. Finally, international experts with experience in the field of the physical, emotional, and cognitive symptoms of BVP participated in an online focus group to assess the relevance and comprehensiveness of the BVQ (IIb). Results The BVQ consisted of two sections. The first section included 50 items scored on a six-point Likert scale arranged into seven constructs (i.e., imbalance, oscillopsia, other physical symptoms, cognitive symptoms, emotional symptoms, limitations and behavioral changes and social life). The second section consisted of four items, scored on a visual analog scale from 0 to 100, to inquire about limitations in daily life, perceived health and expectations regarding future recovery. Interviews with BVP patients [n = 8, 50% female, mean age 56 years (range 24–88 years)] and the expert meeting confirmed face and content validity of the developed BVQ. Conclusion The BVQ, which was developed to assess the spectrum of BVP symptoms and its impact on daily life, proved to have good face and content validity. It can be used to characterize current self-reported symptoms and disability and to evaluate symptom burden before and after therapeutic interventions in future research and clinical practice.
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Affiliation(s)
- Lisa van Stiphout
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, School for Mental Health and Neuroscience, Maastricht, Netherlands
- *Correspondence: Lisa van Stiphout
| | - Israt Hossein
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, School for Mental Health and Neuroscience, Maastricht, Netherlands
| | - Merel Kimman
- Department of Clinical Epidemiology and Medical Technology Assessment (KEMTA), Maastricht University Medical Center, Maastricht, Netherlands
| | - Susan L. Whitney
- Department of Physical Therapy, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Andrianna Ayiotis
- Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Michael Strupp
- Department of Neurology, German Center for Vertigo, Ludwig-Maximilians University, Munich, Germany
| | - Nils Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Angélica Pérez Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Josine Widdershoven
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, School for Mental Health and Neuroscience, Maastricht, Netherlands
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Ángel Ramos-Macías
- Department of Otolaryngology, Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Las Palmas, Spain
| | - Vincent Van Rompaey
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Raymond van de Berg
- Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, School for Mental Health and Neuroscience, Maastricht, Netherlands
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Abstract
Usher syndrome (USH) encompasses a group of clinically and genetically heterogenous disorders defined by the triad of sensorineural hearing loss (SNHL), vestibular dysfunction, and vision loss. USH is the most common cause of deaf blindness. USH is divided clinically into three subtypes-USH1, USH2, and USH3-based on symptom severity, progression, and age of onset. The underlying genetics of these USH forms are, however, significantly more complex, with over a dozen genes linked to the three primary clinical subtypes and other atypical USH phenotypes. Several of these genes are associated with other deaf-blindness syndromes that share significant clinical overlap with USH, pointing to the limits of a clinically based classification system. The genotype-phenotype relationships among USH forms also may vary significantly based on the location and type of mutation in the gene of interest. Understanding these genotype-phenotype relationships and associated natural disease histories is necessary for the successful development and application of gene-based therapies and precision medicine approaches to USH. Currently, the state of knowledge varies widely depending on the gene of interest. Recent studies utilizing next-generation sequencing technology have expanded the list of known pathogenic mutations in USH genes, identified new genes associated with USH-like phenotypes, and proposed algorithms to predict the phenotypic effects of specific categories of allelic variants. Further work is required to validate USH gene causality, and better define USH genotype-phenotype relationships and disease natural histories-particularly for rare mutations-to lay the groundwork for the future of USH treatment.
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van Stiphout L, Lucieer F, Guinand N, Pérez Fornos A, van de Berg M, Van Rompaey V, Widdershoven J, Kingma H, Joore M, van de Berg R. Bilateral vestibulopathy patients' perspectives on vestibular implant treatment: a qualitative study. J Neurol 2021; 269:5249-5257. [PMID: 34894283 PMCID: PMC9467961 DOI: 10.1007/s00415-021-10920-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 03/08/2021] [Accepted: 11/25/2021] [Indexed: 11/29/2022]
Abstract
Objectives The aim of this study was to explore expectations of patients with bilateral vestibulopathy regarding vestibular implant treatment. This could advance the definition of recommendations for future core outcome sets of vestibular implantation and help to determine on which characteristics of bilateral vestibulopathy future vestibular implant research should focus. Methods Semi-structured interviews were conducted with 50 patients diagnosed with bilateral vestibulopathy at Maastricht UMC + . Interviews followed a semi-structured interview guide and were recorded and transcribed. Transcripts were analyzed thematically by two independent researchers. A consensus meeting took place to produce a joint interpretation for greater dimensionality and to confirm key themes. Results Overall, patient expectations centralized around three key themes: (physical) symptom reduction, functions and activities, and quality of life. These themes appeared to be interrelated. Patient expectations focused on the activity walking (in a straight line), reducing the symptom oscillopsia and being able to live the life they had before bilateral vestibulopathy developed. In general, patients indicated to be satisfied with small improvements. Conclusion This study demonstrated that patient expectations regarding a vestibular implant focus on three key themes: symptom reduction, functions and activities, and quality of life. These themes closely match the functional improvements shown in recent vestibular implantation research. The results of this study provide a clear guideline from the patient perspective on which characteristics of bilateral vestibulopathy, future vestibular implant research should focus. Trial registration NL52768.068.15/METC Supplementary Information The online version contains supplementary material available at 10.1007/s00415-021-10920-z.
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Affiliation(s)
- Lisa van Stiphout
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.
| | - Florence Lucieer
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Nils Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Angélica Pérez Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Maurice van de Berg
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Vincent Van Rompaey
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Josine Widdershoven
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Herman Kingma
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Manuela Joore
- Department of Clinical Epidemiology and Medical Technology Assessment (KEMTA), Maastricht University Medical, Maastricht, The Netherlands.,Care and Public Health Research Institute (CAPHRI), Maastricht University, Maastricht, The Netherlands
| | - Raymond van de Berg
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
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Hermann J, Mueller F, Schneider D, O'Toole Bom Braga G, Weber S. Robotic Milling of Electrode Lead Channels During Cochlear Implantation in an ex-vivo Model. Front Surg 2021; 8:742147. [PMID: 34859039 PMCID: PMC8631814 DOI: 10.3389/fsurg.2021.742147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/14/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Robotic cochlear implantation is an emerging surgical technique for patients with sensorineural hearing loss. Access to the middle and inner ear is provided through a small-diameter hole created by a robotic drilling process without a mastoidectomy. Using the same image-guided robotic system, we propose an electrode lead management technique using robotic milling that replaces the standard process of stowing excess electrode lead in the mastoidectomy cavity. Before accessing the middle ear, an electrode channel is milled robotically based on intraoperative planning. The goal is to further standardize cochlear implantation, minimize the risk of iatrogenic intracochlear damage, and to create optimal conditions for a long implant life through protection from external trauma and immobilization in a slight press fit to prevent mechanical fatigue and electrode migrations. Methods: The proposed workflow was executed on 12 ex-vivo temporal bones and evaluated for safety and efficacy. For safety, the difference between planned and resulting channels were measured postoperatively in micro-computed tomography, and the length outside the planned safety margin of 1.0 mm was determined. For efficacy, the channel width and depth were measured to assess the press fit immobilization and the protection from external trauma, respectively. Results: All 12 cases were completed with successful electrode fixations after cochlear insertions. The milled channels stayed within the planned safety margins and the probability of their violation was lower than one in 10,000 patients. Maximal deviations in lateral and depth directions of 0.35 and 0.29 mm were measured, respectively. The channels could be milled with a width that immobilized the electrode leads. The average channel depth was 2.20 mm, while the planned channel depth was 2.30 mm. The shallowest channel depth was 1.82 mm, still deep enough to contain the full 1.30 mm diameter of the electrode used for the experiments. Conclusion: This study proposes a robotic electrode lead management and fixation technique and verified its safety and efficacy in an ex-vivo study. The method of image-guided robotic bone removal presented here with average errors of 0.2 mm and maximal errors below 0.5 mm could be used for a variety of other otologic surgical procedures.
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Affiliation(s)
- Jan Hermann
- ARTORG Center for Biomedical Engineering Research, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Fabian Mueller
- ARTORG Center for Biomedical Engineering Research, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Daniel Schneider
- ARTORG Center for Biomedical Engineering Research, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Gabriela O'Toole Bom Braga
- ARTORG Center for Biomedical Engineering Research, Faculty of Medicine, University of Bern, Bern, Switzerland
| | - Stefan Weber
- ARTORG Center for Biomedical Engineering Research, Faculty of Medicine, University of Bern, Bern, Switzerland
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17
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Peusner KD, Bell NM, Hirsch JC, Beraneck M, Popratiloff A. Understanding the Pathophysiology of Congenital Vestibular Disorders: Current Challenges and Future Directions. Front Neurol 2021; 12:708395. [PMID: 34589045 PMCID: PMC8475631 DOI: 10.3389/fneur.2021.708395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 08/13/2021] [Indexed: 12/13/2022] Open
Abstract
In congenital vestibular disorders (CVDs), children develop an abnormal inner ear before birth and face postnatal challenges to maintain posture, balance, walking, eye-hand coordination, eye tracking, or reading. Only limited information on inner ear pathology is acquired from clinical imaging of the temporal bone or studying histological slides of the temporal bone. A more comprehensive and precise assessment and determination of the underlying mechanisms necessitate analyses of the disorders at the cellular level, which can be achieved using animal models. Two main criteria for a suitable animal model are first, a pathology that mirrors the human disorder, and second, a reproducible experimental outcome leading to statistical power. With over 40 genes that affect inner ear development, the phenotypic abnormalities resulting from congenital vestibular disorders (CVDs) are highly variable. Nonetheless, there is a large subset of CVDs that form a common phenotype of a sac-like inner ear with the semicircular canals missing or dysplastic, and discrete abnormalities in the vestibular sensory organs. We have focused the review on this subset, but to advance research on CVDs we have added other CVDs not forming a sac-like inner ear. We have included examples of animal models used to study these CVDs. Presently, little is known about the central pathology resulting from CVDs at the cellular level in the central vestibular neural network, except for preliminary studies on a chick model that show significant loss of second-order, vestibular reflex projection neurons.
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Affiliation(s)
- Kenna D Peusner
- Department of Neurology, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Nina M Bell
- Department of Neurology, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - June C Hirsch
- Department of Neurology, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States
| | - Mathieu Beraneck
- Université de Paris, Integrative Neuroscience and Cognition Center, CNRS UMR 8002, Paris, France
| | - Anastas Popratiloff
- The George Washington University Nanofabrication and Imaging Center, Washington, DC, United States
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18
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Lanthaler D, Griessner A, Steixner V, Hubner PP, Ranieri M, Cavuscens S, Boutabla A, Zierhofer CM, Perez Fornos A. Speech Perception With Novel Stimulation Strategies for CombinedCochleo-Vestibular Systems. IEEE Trans Neural Syst Rehabil Eng 2021; 29:1644-1650. [PMID: 34398757 DOI: 10.1109/tnsre.2021.3105271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cochlear implants are very well established in the rehabilitation of hearing loss and are regarded as the most successful neuroprostheses to date. While a lot of progress has also been made in the neighboring field of specific vestibular implants, some diseases affect the entire inner ear, leading to both hearing and vestibular hypo- or dysfunction. The proximity of the cochlear and vestibular organs suggests a single combined implant as a means to alleviate the associated impairments. While both organs can be stimulated in a similar way with electric pulses applied through implanted electrodes, the typical phase durations needed in the vestibular system seem to be substantially larger than those typically needed in the cochlear system. Therefore, when using sequential stimulation in a combined implant, the pulse stream to the cochlea is interrupted by comparatively large gaps in which vestibular stimulation can occur. We investigate the impact of these gaps in the auditory stream on speech perception. Specifically, we compare a number of stimulation strategies with different gap lengths and distributions and evaluate whether it is feasible to use them without having a noticeable decline in perception and quality of speech. This is a prerequisite for any practicable stimulation strategy of a combined system and can be investigated even in recipients of a normal cochlear implant. Our results show that there is no significant deterioration in speech perception for the different strategies examined in this paper, leaving the strategies as viable candidates for prospective combined cochleo-vestibular implants.
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19
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van Stiphout L, Lucieer F, Pleshkov M, Van Rompaey V, Widdershoven J, Guinand N, Pérez Fornos A, Kingma H, van de Berg R. Bilateral vestibulopathy decreases self-motion perception. J Neurol 2021; 269:5216-5228. [PMID: 34263351 PMCID: PMC9467944 DOI: 10.1007/s00415-021-10695-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 03/19/2021] [Accepted: 06/29/2021] [Indexed: 11/25/2022]
Abstract
Objective Current diagnostic criteria for bilateral vestibulopathy (BV) primarily involve measurements of vestibular reflexes. Perceptual self-motion thresholds however, are not routinely measured and their clinical value in this specific population is not yet fully determined. Objectives of this study were (1) to compare perceptual self-motion thresholds between BV patients and control subjects, and (2) to explore patterns of self-motion perception performance and vestibular function in BV patients. Methods Thirty-seven BV patients and 34 control subjects were included in this study. Perceptual self-motion thresholds were measured in both groups using a CAREN platform (Motek Medical BV, Amsterdam, The Netherlands). Vestibular function was evaluated (only in BV patients) by the caloric test, torsion swing test, video head impulse test of all semicircular canals, and cervical- and ocular vestibular-evoked myogenic potentials. Differences in thresholds between both groups were analyzed. Hierarchical cluster analysis was performed to visualize patterns between self-motion perception and vestibular function within the group of BV patients. Results Perceptual self-motion thresholds were significantly higher in BV patients compared to control subjects, regarding nearly all rotations and translations (depending on the age group) (p ≤ 0.001). Cluster analysis showed that within the group of BV patients, higher perceptual self-motion thresholds were generally associated with lower vestibular test results (significant for yaw rotation, caloric test, torsion swing test, and video head impulse test (p ≤ 0.001)). Conclusion Self-motion perception is significantly decreased in BV patients compared to control subjects regarding nearly all rotations and translations. Furthermore, decreased self-motion perception is generally associated with lower residual vestibular function in BV patients. Trial registration Trial registration number NL52768.068.15/METC Supplementary Information The online version contains supplementary material available at 10.1007/s00415-021-10695-3.
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Affiliation(s)
- Lisa van Stiphout
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.
| | - Florence Lucieer
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Maksim Pleshkov
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
| | - Vincent Van Rompaey
- Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Josine Widdershoven
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine and Health Sciences, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Nils Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Angélica Pérez Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland
| | - Herman Kingma
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
| | - Raymond van de Berg
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
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20
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3D-reconstructions of Bast's Valve and Membranous Labyrinth: Insights for Vestibular Implantation and Meniere's Disease. Otol Neurotol 2021; 42:e1652-e1660. [PMID: 34172664 DOI: 10.1097/mao.0000000000003239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS/BACKGROUND Bast's valve is a poorly understood inner ear structure located at the junction between pars superior and inferior in the membranous labyrinth. Anatomically precise three-dimensional reconstructions (3D-reconstructions) of Bast's valve can help illuminate the morphology of the valve, and point toward its role in normal physiology and pathological states such as endolymphatic hydrops. This is of particular relevance to the development of a vestibular implant, a device intended to rehabilitate deficits in the vestibular system. METHODS Six postmortem human temporal bones from healthy donors were scanned using a micro-computed tomography (microCT) scanner. The microCT data allowed 3D-reconstructions of the membranous labyrinth, with a particular focus on Bast's valve, vestibule, and cochlear duct. RESULTS The microCT images of Bast's valve showed a rigid lip containing a core of soft tissue, opposing the thin membranous wall of the utricle. The maximum recorded length and width of the rigid lip were 440.4 μm and 88 μm, respectively. The 3D-reconstructions illustrated the slit-like opening of Bast's valve into the utricle, the twisting course of the basal turn of the cochlear duct, and the spatial orientation of utricle and saccule with respect to the stapes footplate. CONCLUSIONS The present study provided a novel anatomical perspective on the microscopic structure of Bast's valve. The interplay between endolymphatic hydrops and Bast's valve is an ongoing area of research, but defining this anatomy in 3D will play a key role in furthering our understanding of the disease process. Implications for vestibular implantation are explored through the various 3D-reconstructions.
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21
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Montardy Q, Wei M, Liu X, Yi T, Zhou Z, Lai J, Zhao B, Besnard S, Tighilet B, Chabbert C, Wang L. Selective optogenetic stimulation of glutamatergic, but not GABAergic, vestibular nuclei neurons induces immediate and reversible postural imbalance in mice. Prog Neurobiol 2021; 204:102085. [PMID: 34171443 DOI: 10.1016/j.pneurobio.2021.102085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 04/21/2021] [Accepted: 05/25/2021] [Indexed: 11/24/2022]
Abstract
Glutamatergic and GABAergic neurons represent the neural components of the medial vestibular nuclei. We assessed the functional role of glutamatergic and GABAergic neuronal pathways arising from the vestibular nuclei (VN) in the maintenance of gait and balance by optogenetically stimulating the VN in VGluT2-cre and GAD2-cre mice. We demonstrate that glutamatergic, but not GABAergic VN neuronal subpopulation is responsible for immediate and strong posturo-locomotor deficits, comparable to unilateral vestibular deafferentation models. During optogenetic stimulation, the support surface dramatically increased in VNVGluT2+ mice, and rapidly fell back to baseline after stimulation, whilst it remained unchanged during similar stimulation of VNGAD2+ mice. This effect persisted when vestibular tactilo kinesthesic plantar inputs were removed. Posturo-locomotor alterations evoked in VNVGluT2+ animals were still present immediately after stimulation, while they disappeared 1 h later. Overall, these results indicate a fundamental role for VNVGluT2+ neurons in balance and posturo-locomotor functions, but not for VNGAD2+ neurons, in this specific context. This new optogenetic approach will be useful to characterize the role of the different VN neuronal populations involved in vestibular physiology and pathophysiology.
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Affiliation(s)
- Q Montardy
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France
| | - M Wei
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - X Liu
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - T Yi
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - Z Zhou
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China; McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - J Lai
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - B Zhao
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China
| | - S Besnard
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; Université de Caen Normandie, CHU de Caen, Caen, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France
| | - B Tighilet
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France.
| | - C Chabbert
- Aix Marseille University-CNRS, Laboratory of Sensory and Cognitive Neurosciences, UMR 7260, Team Pathophysiology and Therapy of Vestibular Disorders, Marseille, France; GDR Physiopathologie Vestibulaire - unité GDR2074 CNRS, France.
| | - L Wang
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, CAS Center for Excellence in Brain Science and Intelligence Technology, The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.
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22
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Rodriguez Montesdeoca I, Ramos de Miguel A, González JCF, Barreiro SB, Pérez Fernández N, Vanspauwen R, Ramos-Macias A. Differences in Vestibular-Evoked Myogenic Potential Responses by Using Cochlear Implant and Otolith Organ Direct Stimulation. Front Neurol 2021; 12:663803. [PMID: 34113311 PMCID: PMC8185293 DOI: 10.3389/fneur.2021.663803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 04/08/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Several studies have demonstrated the possibility to obtain vestibular potentials elicited with electrical stimulation from cochlear and vestibular implants. The objective of this study is to analyze the vestibular-evoked myogenic potentials (VEMPs) obtained from patients implanted with cochlear and vestibulo-cochlear implant. Material and Methods: We compared two groups: in the first group, four cochlear implant (CI) recipients with present acoustic cVEMPs before CI surgery were included. In the second group, three patients with bilaterally absent cVEMPs and bilateral vestibular dysfunction were selected. The latter group received a unilateral cochleo-vestibular implant. We analyze the electrically elicited cVEMPs in all patients after stimulation with cochlear and vestibular electrode array stimulation. Results: We present the results obtained post-operatively in both groups. All patients (100%) with direct electrical vestibular stimulation via the vestibular electrode array had present cVEMPs. The P1 and N1 latencies were 11.33-13.6 ms and 18.3-21 ms, respectively. In CI patients, electrical cVEMPs were present only in one of the four subjects (25%) with cochlear implant ("cross") stimulation, and P1 and N1 latencies were 9.67 and 16.33, respectively. In these patients, the responses present shorter latencies than those observed acoustically. Conclusions: Electrically evoked cVEMPs can be present after cochlear and vestibular stimulation and suggest stimulation of vestibular elements, although clinical effect must be further studied.
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Affiliation(s)
- Isaura Rodriguez Montesdeoca
- Department of Otolaryngology, Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Las Palmas, Spain
| | - Angel Ramos de Miguel
- Hearing and Balance Laboratory, Las Palmas de Gran Canaria University (SIANI), Las Palmas, Spain
| | - Juan Carlos Falcon González
- Department of Otolaryngology, Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Las Palmas, Spain
| | - Silvia Borkoski Barreiro
- Department of Otolaryngology, Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Las Palmas, Spain
| | | | - Robby Vanspauwen
- European Institute for Otorhinolaryngology Head and Neck Surgery, Gasthuiszusters Antwerpen Hospitals Antwerp, Wilrijk, Belgium
| | - Angel Ramos-Macias
- Department of Otolaryngology, Head and Neck Surgery, Complejo Hospitalario Universitario Insular Materno Infantil de Gran Canaria, Las Palmas, Spain.,Hearing and Balance Laboratory, Las Palmas de Gran Canaria University (SIANI), Las Palmas, Spain
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23
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Dlugaiczyk J. Rare Disorders of the Vestibular Labyrinth: of Zebras, Chameleons and Wolves in Sheep's Clothing. Laryngorhinootologie 2021; 100:S1-S40. [PMID: 34352900 PMCID: PMC8363216 DOI: 10.1055/a-1349-7475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The differential diagnosis of vertigo syndromes is a challenging issue, as many - and in particular - rare disorders of the vestibular labyrinth can hide behind the very common symptoms of "vertigo" and "dizziness". The following article presents an overview of those rare disorders of the balance organ that are of special interest for the otorhinolaryngologist dealing with vertigo disorders. For a better orientation, these disorders are categorized as acute (AVS), episodic (EVS) and chronic vestibular syndromes (CVS) according to their clinical presentation. The main focus lies on EVS sorted by their duration and the presence/absence of triggering factors (seconds, no triggers: vestibular paroxysmia, Tumarkin attacks; seconds, sound and pressure induced: "third window" syndromes; seconds to minutes, positional: rare variants and differential diagnoses of benign paroxysmal positional vertigo; hours to days, spontaneous: intralabyrinthine schwannomas, endolymphatic sac tumors, autoimmune disorders of the inner ear). Furthermore, rare causes of AVS (inferior vestibular neuritis, otolith organ specific dysfunction, vascular labyrinthine disorders, acute bilateral vestibulopathy) and CVS (chronic bilateral vestibulopathy) are covered. In each case, special emphasis is laid on the decisive diagnostic test for the identification of the rare disease and "red flags" for potentially dangerous disorders (e. g. labyrinthine infarction/hemorrhage). Thus, this chapter may serve as a clinical companion for the otorhinolaryngologist aiding in the efficient diagnosis and treatment of rare disorders of the vestibular labyrinth.
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Affiliation(s)
- Julia Dlugaiczyk
- Klinik für Ohren-, Nasen-, Hals- und Gesichtschirurgie
& Interdisziplinäres Zentrum für Schwindel und
neurologische Sehstörungen, Universitätsspital Zürich
(USZ), Universität Zürich (UZH), Zürich,
Schweiz
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24
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Abstract
PURPOSE OF REVIEW This article reviews the causes of tinnitus, hyperacusis, and otalgia, as well as hearing loss relevant for clinicians in the field of neurology. RECENT FINDINGS Important causes of unilateral and bilateral tinnitus are discussed, including those that are treatable or caused by serious structural or vascular causes. Concepts of hyperacusis and misophonia are covered, along with various types of neurologic disorders that can lead to pain in the ear. Hearing loss is common but not always purely otologic. SUMMARY Tinnitus and hearing loss are common symptoms that are sometimes related to a primary neurologic disorder. This review, tailored to neurologists who care for patients who may be referred to or encountered in neurology practice, provides information on hearing disorders, how to recognize when a neurologic process may be involved, and when to refer to otolaryngology or other specialists.
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25
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An Implanted Vestibular Prosthesis Improves Spatial Orientation in Animals with Severe Vestibular Damage. J Neurosci 2021; 41:3879-3888. [PMID: 33731447 DOI: 10.1523/jneurosci.2204-20.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 02/10/2021] [Accepted: 03/08/2021] [Indexed: 11/21/2022] Open
Abstract
Gravity is a pervasive environmental stimulus, and accurate graviception is required for optimal spatial orientation and postural stability. The primary graviceptors are the vestibular organs, which include angular velocity (semicircular canals) and linear acceleration (otolith organs) sensors. Graviception is degraded in patients with vestibular damage, resulting in spatial misperception and imbalance. Since minimal therapy is available for these patients, substantial effort has focused on developing a vestibular prosthesis or vestibular implant (VI) that reproduces information normally provided by the canals (since reproducing otolith function is very challenging technically). Prior studies demonstrated that angular eye velocity responses could be driven by canal VI-mediated angular head velocity information, but it remains unknown whether a canal VI could improve spatial perception and posture since these behaviors require accurate estimates of angular head position in space relative to gravity. Here, we tested the hypothesis that a canal VI that transduces angular head velocity and provides this information to the brain via motion-modulated electrical stimulation of canal afferent nerves could improve the perception of angular head position relative to gravity in monkeys with severe vestibular damage. Using a subjective visual vertical task, we found that normal female monkeys accurately sensed the orientation of the head relative to gravity during dynamic tilts, that this ability was degraded following bilateral vestibular damage, and improved when the canal VI was used. These results demonstrate that a canal VI can improve graviception in vestibulopathic animals, suggesting that it could reduce the disabling perceptual and postural deficits experienced by patients with severe vestibular damage.SIGNIFICANCE STATEMENT Patients with vestibular damage experience impaired vision, spatial perception, and balance, symptoms that could potentially respond to a vestibular implant (VI). Anatomic features facilitate semicircular canal (angular velocity) prosthetics but inhibit approaches with the otolith (linear acceleration) organs, and canal VIs that sense angular head velocity can generate compensatory eye velocity responses in vestibulopathic subjects. Can the brain use canal VI head velocity information to improve estimates of head orientation (e.g., head position relative to gravity), which is a prerequisite for accurate spatial perception and posture? Here we show that a canal VI can improve the perception of head orientation in vestibulopathic monkeys, results that are highly significant because they suggest that VIs mimicking canal function can improve spatial orientation and balance in vestibulopathic patients.
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Chow MR, Ayiotis AI, Schoo DP, Gimmon Y, Lane KE, Morris BJ, Rahman MA, Valentin NS, Boutros PJ, Bowditch SP, Ward BK, Sun DQ, Treviño Guajardo C, Schubert MC, Carey JP, Della Santina CC. Posture, Gait, Quality of Life, and Hearing with a Vestibular Implant. N Engl J Med 2021; 384:521-532. [PMID: 33567192 PMCID: PMC8477665 DOI: 10.1056/nejmoa2020457] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Bilateral vestibular hypofunction is associated with chronic disequilibrium, postural instability, and unsteady gait owing to failure of vestibular reflexes that stabilize the eyes, head, and body. A vestibular implant may be effective in alleviating symptoms. METHODS Persons who had had ototoxic (7 participants) or idiopathic (1 participant) bilateral vestibular hypofunction for 2 to 23 years underwent unilateral implantation of a prosthesis that electrically stimulates the three semicircular canal branches of the vestibular nerve. Clinical outcomes included the score on the Bruininks-Oseretsky Test of Motor Proficiency balance subtest (range, 0 to 36, with higher scores indicating better balance), time to failure on the modified Romberg test (range, 0 to 30 seconds), score on the Dynamic Gait Index (range, 0 to 24, with higher scores indicating better gait performance), time needed to complete the Timed Up and Go test, gait speed, pure-tone auditory detection thresholds, speech discrimination scores, and quality of life. We compared participants' results at baseline (before implantation) with those at 6 months (8 participants) and at 1 year (6 participants) with the device set in its usual treatment mode (varying stimulus pulse rate and amplitude to represent rotational head motion) and in a placebo mode (holding pulse rate and amplitude constant). RESULTS The median scores at baseline and at 6 months on the Bruininks-Oseretsky test were 17.5 and 21.0, respectively (median within-participant difference, 5.5 points; 95% confidence interval [CI], 0 to 10.0); the median times on the modified Romberg test were 3.6 seconds and 8.3 seconds (difference, 5.1; 95% CI, 1.5 to 27.6); the median scores on the Dynamic Gait Index were 12.5 and 22.5 (difference, 10.5 points; 95% CI, 1.5 to 12.0); the median times on the Timed Up and Go test were 11.0 seconds and 8.7 seconds (difference, 2.3; 95% CI, -1.7 to 5.0); and the median speeds on the gait-speed test were 1.03 m per second and 1.10 m per second (difference, 0.13; 95% CI, -0.25 to 0.30). Placebo-mode testing confirmed that improvements were due to treatment-mode stimulation. Among the 6 participants who were also assessed at 1 year, the median within-participant changes from baseline to 1 year were generally consistent with results at 6 months. Implantation caused ipsilateral hearing loss, with the air-conducted pure-tone average detection threshold at 6 months increasing by 3 to 16 dB in 5 participants and by 74 to 104 dB in 3 participants. Changes in participant-reported disability and quality of life paralleled changes in posture and gait. CONCLUSIONS Six months and 1 year after unilateral implantation of a vestibular prosthesis for bilateral vestibular hypofunction, measures of posture, gait, and quality of life were generally in the direction of improvement from baseline, but hearing was reduced in the ear with the implant in all but 1 participant. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT02725463.).
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Affiliation(s)
- Margaret R Chow
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Andrianna I Ayiotis
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Desi P Schoo
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Yoav Gimmon
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Kelly E Lane
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Brian J Morris
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Mehdi A Rahman
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Nicolas S Valentin
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Peter J Boutros
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Stephen P Bowditch
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Bryan K Ward
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Daniel Q Sun
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Carolina Treviño Guajardo
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Michael C Schubert
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - John P Carey
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
| | - Charles C Della Santina
- From the Departments of Otolaryngology-Head and Neck Surgery (M.R.C., A.I.A., D.P.S., Y.G., K.E.L., B.J.M., P.J.B., S.P.B., B.K.W., D.Q.S., C.T.G., M.C.S., J.P.C., C.C.D.S.) and Biomedical Engineering (M.R.C., A.I.A., B.J.M., P.J.B., C.C.D.S.), Johns Hopkins University School of Medicine, and Labyrinth Devices (M.A.R., N.S.V., C.C.D.S.) - both in Baltimore
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Lucieer FMP, Van Hecke R, van Stiphout L, Duijn S, Perez-Fornos A, Guinand N, Van Rompaey V, Kingma H, Joore M, van de Berg R. Bilateral vestibulopathy: beyond imbalance and oscillopsia. J Neurol 2020; 267:241-255. [PMID: 33030608 PMCID: PMC7718190 DOI: 10.1007/s00415-020-10243-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/20/2020] [Accepted: 09/22/2020] [Indexed: 01/04/2023]
Abstract
Objective To optimize the current diagnostic and treatment procedures for patients with bilateral vestibulopathy (BV), this study aimed to determine the complete spectrum of symptoms associated with BV. Method A prospective mixed-method study design was used. Qualitative data were collected by performing semi-structured interviews about symptoms, context, and behavior. The interviews were recorded and transcribed until no new information was obtained. Transcriptions were analyzed in consensus by two independent researchers. In comparison to the qualitative results, quantitative data were collected using the Dizziness Handicap Inventory (DHI), Hospital Anxiety and Depression Scale (HADS) and a health-related quality of life questionnaire (EQ-5D-5L). Results Eighteen interviews were transcribed. Reported symptoms were divided into fourteen physical symptoms, four cognitive symptoms, and six emotions. Symptoms increased in many situations, such as darkness (100%), uneven ground (61%), cycling (94%) or driving a car (56%). These symptoms associated with BV often resulted in behavioral changes: activities were performed more slowly, with greater attention, or were avoided. The DHI showed a mean score of severe handicap (54.67). The HADS questionnaire showed on average normal results (anxiety = 7.67, depression = 6.22). The EQ-5D-5L demonstrated a mean index value of 0.680, which is lower compared to the Dutch age-adjusted reference 0.839 (60–70 years). Conclusion BV frequently leads to physical, cognitive, and emotional complaints, which often results in a diminished quality of life. Importantly, this wide range of symptoms is currently underrated in literature and should be taken into consideration during the development of candidacy criteria and/or outcome measures for therapeutic interventions such as the vestibular implant. Electronic supplementary material The online version of this article (10.1007/s00415-020-10243-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- F M P Lucieer
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.
| | - R Van Hecke
- Department of Rehabilitation Sciences, University of Ghent, Ghent, Belgium
| | - L van Stiphout
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - S Duijn
- Faculty of Health, Medicine and life Sciences, University of Maastricht, Maastricht, The Netherlands
| | - A Perez-Fornos
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences,, Geneva University Hospitals, Geneva, Switzerland
| | - N Guinand
- Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences,, Geneva University Hospitals, Geneva, Switzerland
| | - V Van Rompaey
- Faculty of Physics, Tomsk State Research University, Tomsk, Russian Federation
| | - H Kingma
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - M Joore
- Department of Clinical Epidemiology and Medical Technology Assessment (KEMTA), Care and Public Health Research Institute (CAPHRI) of the Faculty of Health, Medicine and Life Sciences of Maastricht University (FHML), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - R van de Berg
- Department of Otorhinolaryngology and Head and Neck Surgery, Division of Balance Disorders, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
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Simultaneous activation of multiple vestibular pathways upon electrical stimulation of semicircular canal afferents. J Neurol 2020; 267:273-284. [PMID: 32778921 PMCID: PMC7718208 DOI: 10.1007/s00415-020-10120-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/02/2020] [Accepted: 07/27/2020] [Indexed: 11/23/2022]
Abstract
Background and purpose Vestibular implants seem to be a promising treatment for patients suffering from severe bilateral vestibulopathy. To optimize outcomes, we need to investigate how, and to which extent, the different vestibular pathways are activated. Here we characterized the simultaneous responses to electrical stimuli of three different vestibular pathways. Methods Three vestibular implant recipients were included. First, activation thresholds and amplitude growth functions of electrically evoked vestibulo-ocular reflexes (eVOR), cervical myogenic potentials (ecVEMPs) and vestibular percepts (vestibulo-thalamo-cortical, VTC) were recorded upon stimulation with single, biphasic current pulses (200 µs/phase) delivered through five different vestibular electrodes. Latencies of eVOR and ecVEMPs were also characterized. Then we compared the amplitude growth functions of the three pathways using different stimulation profiles (1-pulse, 200 µs/phase; 1-pulse, 50 µs/phase; 4-pulses, 50 µs/phase, 1600 pulses-per-second) in one patient (two electrodes). Results The median latencies of the eVOR and ecVEMPs were 8 ms (8–9 ms) and 10.2 ms (9.6–11.8 ms), respectively. While the amplitude of eVOR and ecVEMP responses increased with increasing stimulation current, the VTC pathway showed a different, step-like behavior. In this study, the 200 µs/phase paradigm appeared to give the best balance to enhance responses at lower stimulation currents. Conclusions This study is a first attempt to evaluate the simultaneous activation of different vestibular pathways. However, this issue deserves further and more detailed investigation to determine the actual possibility of selective stimulation of a given pathway, as well as the functional impact of the contribution of each pathway to the overall rehabilitation process.
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Thomas C, Truong D, Clark TK, Datta A. Understanding current flow in Galvanic Vestibular Stimulation: A Computational Study. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:2442-2446. [PMID: 33018500 DOI: 10.1109/embc44109.2020.9176716] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Galvanic vestibular stimulation (GVS) involves the application of electrical current through electrodes placed exclusively at the mastoids or in combination with electrodes placed on other regions. It is a simple, safe modality to modulate and probe vestibular function. Despite a long history of use, it continues to be primarily used as a research tool with no fully developed therapeutic use. This is partly due to the fact that to further advance this technique, a better understanding of what structures are stimulated and by how much is needed. While models have been proposed to explain response, cellular and structural substrates confirmed empirically, the exact current flow pattern has not been investigated.The goal of this study is to therefore determine current flow patterns in GVS. In order to do so, we developed the first ultrahigh-resolution finite element model of GVS incorporating the tiny structures of interest in the inner ear. We simulated the Bilateral-Bipolar, Bilateral-Monopolar, and the Unilateral-Monopolar configurations. Specifically, we generated surface electric field magnitude plots for the brain and for structures considered most relevant to GVS mechanism of action- the semi-circular canals (SCC) and the otolith.Findings show that the Bilateral-Bipolar configuration results in the most spatially restricted flow while the Unilateral-Monopolar configuration results in the most diffuse. With respect to SCC and the otolith, both Bilateral-Bipolar and Bilateral-Monopolar configurations led to similar flow in both the left and right pairs. For the Unilateral-Monopolar configuration, we observed increased flow in the left pair.We expect via this first model developed for GVS, researchers investigating this technique to have a better understanding of the effects of different configurations. Anatomically detailed models like these may also help understand the mechanism of action and may guide the rational design of future GVS administration.
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Guyot JP, Guinand N, Perez Fornos A. Tribute to Bernard Cohen - Whose Pioneering Work Made the Vestibular Implant Possible. Front Neurol 2020; 11:452. [PMID: 32536904 PMCID: PMC7267219 DOI: 10.3389/fneur.2020.00452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 04/28/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Jean-Philippe Guyot
- Division of ENT and Head-and-Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Nils Guinand
- Division of ENT and Head-and-Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Angelica Perez Fornos
- Division of ENT and Head-and-Neck Surgery, Geneva University Hospitals, Geneva, Switzerland
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Crétallaz C, Boutabla A, Cavuscens S, Ranieri M, Nguyen TAK, Kingma H, Van De Berg R, Guinand N, Pérez Fornos A. Influence of systematic variations of the stimulation profile on responses evoked with a vestibular implant prototype in humans. J Neural Eng 2020; 17:036027. [PMID: 32213673 PMCID: PMC8630998 DOI: 10.1088/1741-2552/ab8342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To explore the impact of different electrical stimulation profiles in human recipients of the Geneva-Maastricht vestibular implant prototypes. APPROACH Four implanted patients were recruited for this study. We investigated the relative efficacy of systematic variations of the electrical stimulus profile (phase duration, pulse rate, baseline level, modulation depth) in evoking vestibulo-ocular (eVOR) and perceptual responses. MAIN RESULTS Shorter phase durations and, to a lesser extent, slower pulse rates allowed maximizing the electrical dynamic range available for eliciting a wider range of intensities of vestibular percepts. When either the phase duration or the pulse rate was held constant, current modulation depth was the factor that had the most significant impact on peak velocity of the eVOR. SIGNIFICANCE Our results identified important parametric variations that influence the measured responses. Furthermore, we observed that not all vestibular pathways seem equally sensitive to the electrical stimulus when the electrodes are placed in the semicircular canals and monopolar stimulation is used. This opens the door to evaluating new stimulation strategies for a vestibular implant, and suggests the possibility of selectively activating one vestibular pathway or the other in order to optimize rehabilitation outcomes.
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Affiliation(s)
- Céline Crétallaz
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
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Pauna HF, Knoll RM, Lubner RJ, Brodsky JR, Cushing SL, Hyppolito MA, Nadol JB, Remenschneider AK, Kozin ED. Histopathological changes to the peripheral vestibular system following meningitic labyrinthitis. Laryngoscope Investig Otolaryngol 2020; 5:256-266. [PMID: 32337357 PMCID: PMC7178454 DOI: 10.1002/lio2.349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/18/2019] [Accepted: 12/31/2019] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE While cochlear ossification is a common sequalae of meningitic labyrinthitis, less is known about the effects of meningitis on peripheral vestibular end organs. Herein, we investigate histopathologic changes in the peripheral vestibular system and cochlea in patients with a history of meningitic labyrinthitis. METHODS Temporal bone (TB) specimens from patients with a history of meningitis were evaluated and compared to age-matched controls. Specimens were evaluated by light microscopy and assessed for qualitative changes, including the presence of vestibular and/or cochlear endolymphatic hydrops, presence and location of inflammatory cells, new bone formation, and labyrinthitis ossificans; and quantitative changes, including Scarpa's ganglion neuron (ScGN) and spiral ganglion neuron (SGN) counts. RESULTS Fifteen TB from 10 individuals met inclusion and exclusion criteria. Presence of inflammatory cells and fibrous tissue was found in 5 TB. Of these, evidence of labyrinthitis ossificans was found in 2 TB. In the peripheral vestibular system, mild to severe degeneration of the vestibular membranous labyrinth was identified in 60% of cases (n = 9 TBs). There was a 21.2% decrease (range, 3%-64%) in the mean total count of ScGN in patients with meningitis, compared to age-matched controls. In the cochlea, there was a 45% decrease (range, 25.3%-80.9%) in the mean total count of SGN compared to age-matched controls (n = 14 TBs). CONCLUSIONS Otopathologic analysis of TB from patients with a history of meningitic labyrinthitis demonstrated distinct peripheral vestibular changes. Future research may help to delineate potential mechanisms for the observed otopathologic changes following meningitis. LEVEL OF EVIDENCE N/A.
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Affiliation(s)
- Henrique F. Pauna
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck SurgeryRibeirão Preto Medical School (FMRP‐USP), University of São PauloRibeirão PretoSão PauloBrazil
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
| | - Renata M. Knoll
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Department of OtolaryngologyHarvard Medical SchoolBostonMassachusetts
| | - Rory J. Lubner
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Department of OtolaryngologyHarvard Medical SchoolBostonMassachusetts
| | - Jacob R. Brodsky
- Department of Otolaryngology and Communication EnhancementBoston Children's HospitalBostonMassachusetts
| | - Sharon L. Cushing
- Department of Otolaryngology, Head & Neck SurgeryHospital for Sick Children, University of TorontoTorontoOntarioCanada
| | - Miguel A. Hyppolito
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck SurgeryRibeirão Preto Medical School (FMRP‐USP), University of São PauloRibeirão PretoSão PauloBrazil
| | - Joseph B. Nadol
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Department of OtolaryngologyHarvard Medical SchoolBostonMassachusetts
| | - Aaron K. Remenschneider
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Department of OtolaryngologyHarvard Medical SchoolBostonMassachusetts
| | - Elliott D. Kozin
- Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Otopathology Laboratory, Department of OtolaryngologyMassachusetts Eye and EarBostonMassachusetts
- Department of OtolaryngologyHarvard Medical SchoolBostonMassachusetts
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33
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Prospective cohort study on the predictors of fall risk in 119 patients with bilateral vestibulopathy. PLoS One 2020; 15:e0228768. [PMID: 32150553 PMCID: PMC7062241 DOI: 10.1371/journal.pone.0228768] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 01/23/2020] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To identify predictive factors for falls in patients with bilateral vestibulopathy (BV). Specific variables contributing to the general work-up of a vestibular patient were compared between BV patients experiencing falls and those who did not. DESIGN Prospective multi-centric cohort study. SETTING Department of Otorhinolaryngology & Head and Neck Surgery at two tertiary referral centers: Antwerp University Hospital and Maastricht University Medical Center. PARTICIPANTS In total, 119 BV patients were included. BV diagnosis was defined in accordance with the diagnostic BV criteria, established by the Bárány Society in 2017. MAIN OUTCOME MEASURES Patients were divided into fallers and non-fallers, depending on the experience of one or more falls in the preceding 12 months. Residual vestibular function on caloric testing, rotatory chair testing, video head impulse test (vHIT) and cervical vestibular evoked myogenic potentials (cVEMP) was evaluated as a predictive factor for falls. Furthermore, hearing function (speech perception in noise (SPIN)), sound localization performance, etiology, disease duration, sport practice, scores on the Dizziness Handicap Inventory (DHI) and the Oscillopsia Severity Questionnaire (OSQ) were compared between fallers and non-fallers. RESULTS Forty-five (39%) patients reported falls. In a sub-analysis in the patients recruited at UZA (n = 69), 20% experienced three or more falls and three patients (4%) suffered from severe fall-related injuries. The DHI score and the OSQ score were significantly higher in fallers. Residual vestibular function, SPIN, sound localization performance, etiology, disease duration, age and sport practice did not differ between fallers and non-fallers. CONCLUSIONS Falls and (severe) fall-related injuries are frequent among BV patients. A DHI score > 47 and an OSQ score > 27.5 might be indicative for BV patients at risk for falls, with a sensitivity of 70% and specificity of 60%. Residual vestibular function captured by single vestibular tests (vHIT, calorics, rotatory chair, cVEMP) or by overall vestibular function defined as the number of impaired vestibular sensors are not suitable to distinguish fallers and non-fallers in a BV population.
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Géléoc GGS, El-Amraoui A. Disease mechanisms and gene therapy for Usher syndrome. Hear Res 2020; 394:107932. [PMID: 32199721 DOI: 10.1016/j.heares.2020.107932] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/03/2020] [Accepted: 02/26/2020] [Indexed: 12/11/2022]
Abstract
Usher syndrome (USH) is a major cause of deaf-blindness in humans, affecting ∼400 000 patients worldwide. Three clinical subtypes, USH1-3, have been defined, with 10 USH genes identified so far. In recent years, in addition to identification of new Usher genes and diagnostic tools, major progress has been made in understanding the role of Usher proteins and how they cooperate through interaction networks to ensure proper development, architecture and function of the stereociliary bundle at the apex of sensory hair cells in the inner ear. Several Usher mouse models of known human Usher genes have been characterized. These mice faithfully reproduce the auditory phenotype associated with Usher syndrome and the vestibular phenotype associated with some mutations in USH genes, particularly USH1. Interestingly, very few mouse models of Usher syndrome recapitulate the retinal phenotype associated with the disease in human. Usher patients can benefit from hearing aids or cochlear implants, which partially alleviate auditory sensory deprivation. However, there are currently no biological treatments available for auditory or visual dysfunction in Usher patients. Development of novel therapies for Usher syndrome has sprouted over the past decade, building on recent progress in gene transfer and new gene editing tools. Promising success demonstrating recovery of hearing and balance functions have been obtained via distinct therapeutic strategies in animal models. Clinical translation to Usher patients, however, calls for further improvements and concerted efforts to overcome the challenges ahead.
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Affiliation(s)
- Gwenaelle G S Géléoc
- Boston Children's Hospital and Harvard Medical School, 3, Blackfan circle, Center for Life Science, 03001, Boston, MA, 02115, United States.
| | - Aziz El-Amraoui
- Unit Progressive Sensory Disorders, Institut Pasteur, INSERM-UMRS1120, Sorbonne Université, 25 rue du Dr. Roux, 75015, Paris, France.
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Kim G, Lee S, Kim KS. Dominant parameter of galvanic vestibular stimulation for the non-associative learning processes. Med Biol Eng Comput 2020; 58:701-708. [PMID: 31953797 DOI: 10.1007/s11517-019-02117-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 12/28/2019] [Indexed: 12/22/2022]
Abstract
Electrical stimulus is one of the common stimulating methods, and Galvanic vestibular stimulation (GVS) is the oldest form as an electrical stimulation. Nevertheless, GVS is still considered as a secondary stimulating tool for the medical purposes. Even though some unarguable findings have made using GVS, its use has been limited because of its ambiguity as an input source. For better understanding, many previous studies mainly focused on its functional effects, like the ocular reflexes. However, its fundamental effects on the neural activities are still elusive, such as the dominant influences by different parameters of GVS. Here we compared the effects on the neuronal responses by applying two different parameters, strength and rate, of GVS. To assess the dominance on the neuronal responses to these parameters, we designed three independent stimuli. Those stimuli were multiply applied to obtain the responding slopes based on the mechanism of non-associative learning processes, and the effects on the neurons were calculated as an inner angle between two responding slopes. Out of 23 neurons, 15 (65.2%) units were affected more by the strength with a statistical significance (p = 0.047). The ranges of the inner angles also implied the strength (- 3.354°~2.063°) mainly modulated by the neuronal responses comparing with those by the rate (- 2.001°~1.975°). The dominance of the parameters was closely related with the neuronal sensitivity to stimulation (SE) (p = 0.018), while there were few relations with the neuronal regularity, directional preference (DP), and the physiological response (PR) (p > 0.059). Thus, the neural information related with the dominance was delivered by the irregular neurons, and these types of neurons should be the targets for the stimulation. Graphical abstract.
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Affiliation(s)
- Gyutae Kim
- Research Institute for Aerospace Medicine, Inha University, High-Tech center #303, 100 Inharo, Namgu, InCheon, 402-751, South Korea.
- Institute for Information and Electronics Research, Inha University, High-Tech center #716, 100 Inharo, Namgu, InCheon, 402-751, South Korea.
| | - Sangmin Lee
- Institute for Information and Electronics Research, Inha University, High-Tech center #716, 100 Inharo, Namgu, InCheon, 402-751, South Korea
- Department of Electronic Engineering, Inha University, High-Tech center #704, 100 Inharo, Namgu, InCheon, 402-751, South Korea
| | - Kyu-Sung Kim
- Research Institute for Aerospace Medicine, Inha University, High-Tech center #303, 100 Inharo, Namgu, InCheon, 402-751, South Korea
- Department of Otolaryngology Head & Neck Surg., Inha University Hospital, 27 Inhang-ro, Jung-Gu, Incheon, 400-711, South Korea
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36
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Wimmer W, Anschuetz L, Weder S, Wagner F, Delingette H, Caversaccio M. Human bony labyrinth dataset: Co-registered CT and micro-CT images, surface models and anatomical landmarks. Data Brief 2019; 27:104782. [PMID: 31763421 PMCID: PMC6864122 DOI: 10.1016/j.dib.2019.104782] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/30/2019] [Accepted: 11/01/2019] [Indexed: 12/24/2022] Open
Abstract
The presented data set consists of images, labels and surface models of 23 human bony labyrinths. For each specimen clinical computed tomography (CT) and co-registered high-resolution micro-CT images were acquired. Using the images, the bony labyrinth was segmented and 3D surface models were generated. Each specimen is accompanied by a description file containing the coordinates of anatomical landmarks and the corresponding cochlear coordinate system. The data set can be used to study the morphology of the inner ear or to evaluate segmentation algorithm as used for the preoperative planning of surgical procedures such as cochlear implantation.
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Affiliation(s)
- Wilhelm Wimmer
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, Switzerland
- Hearing Research Laboratory, ARTORG Center for Biomedical Engineering Research, University of Bern, Switzerland
- Université Côte d’Azur, Inria, Epione, Sophia Antipolis, France
| | - Lukas Anschuetz
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, Switzerland
| | - Stefan Weder
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, Switzerland
| | - Franca Wagner
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, Switzerland
| | | | - Marco Caversaccio
- Department of ENT, Head and Neck Surgery, Inselspital, Bern University Hospital, Switzerland
- Hearing Research Laboratory, ARTORG Center for Biomedical Engineering Research, University of Bern, Switzerland
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Hageman KN, Chow MR, Roberts D, Boutros PJ, Tooker A, Lee K, Felix S, Pannu SS, Haque R, Della Santina CC. Binocular 3D otolith-ocular reflexes: responses of chinchillas to prosthetic electrical stimulation targeting the utricle and saccule. J Neurophysiol 2019; 123:259-276. [PMID: 31747349 DOI: 10.1152/jn.00883.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
From animal experiments by Cohen and Suzuki et al. in the 1960s to the first-in-human clinical trials now in progress, prosthetic electrical stimulation targeting semicircular canal branches of the vestibular nerve has proven effective at driving directionally appropriate vestibulo-ocular reflex eye movements, postural responses, and perception. That work was considerably facilitated by the fact that all hair cells and primary afferent neurons in each canal have the same directional sensitivity to head rotation, the three canals' ampullary nerves are geometrically distinct from one another, and electrically evoked three-dimensional (3D) canal-ocular reflex responses approximate a simple vector sum of linearly independent components representing relative excitation of each of the three canals. In contrast, selective prosthetic stimulation of the utricle and saccule has been difficult to achieve, because hair cells and afferents with many different directional sensitivities are densely packed in those endorgans and the relationship between 3D otolith-ocular reflex responses and the natural and/or prosthetic stimuli that elicit them is more complex. As a result, controversy exists regarding whether selective, controllable stimulation of electrically evoked otolith-ocular reflexes (eeOOR) is possible. Using micromachined, planar arrays of electrodes implanted in the labyrinth, we quantified 3D, binocular eeOOR responses to prosthetic electrical stimulation targeting the utricle, saccule, and semicircular canals of alert chinchillas. Stimuli delivered via near-bipolar electrode pairs near the maculae elicited sustained ocular countertilt responses that grew reliably with pulse rate and pulse amplitude, varied in direction according to which stimulating electrode was employed, and exhibited temporal dynamics consistent with responses expected for isolated macular stimulation.NEW & NOTEWORTHY As the second in a pair of papers on Binocular 3D Otolith-Ocular Reflexes, this paper describes new planar electrode arrays and vestibular prosthesis architecture designed to target the three semicircular canals and the utricle and saccule. With this technological advancement, electrically evoked otolith-ocular reflexes due to stimulation via utricle- and saccule-targeted electrodes were recorded in chinchillas. Results demonstrate advances toward achieving selective stimulation of the utricle and saccule.
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Affiliation(s)
- Kristin N Hageman
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Margaret R Chow
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Dale Roberts
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Peter J Boutros
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Angela Tooker
- Lawrence Livermore National Laboratory, Livermore, California
| | - Kye Lee
- Lawrence Livermore National Laboratory, Livermore, California
| | - Sarah Felix
- Lawrence Livermore National Laboratory, Livermore, California
| | | | - Razi Haque
- Lawrence Livermore National Laboratory, Livermore, California
| | - Charles C Della Santina
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland.,Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland
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Boutros PJ, Schoo DP, Rahman M, Valentin NS, Chow MR, Ayiotis AI, Morris BJ, Hofner A, Rascon AM, Marx A, Deas R, Fridman GY, Davidovics NS, Ward BK, Treviño C, Bowditch SP, Roberts DC, Lane KE, Gimmon Y, Schubert MC, Carey JP, Jaeger A, Della Santina CC. Continuous vestibular implant stimulation partially restores eye-stabilizing reflexes. JCI Insight 2019; 4:128397. [PMID: 31723056 DOI: 10.1172/jci.insight.128397] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 10/04/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUNDBilateral loss of vestibular (inner ear inertial) sensation causes chronically blurred vision during head movement, postural instability, and increased fall risk. Individuals who fail to compensate despite rehabilitation therapy have no adequate treatment options. Analogous to hearing restoration via cochlear implants, prosthetic electrical stimulation of vestibular nerve branches to encode head motion has garnered interest as a potential treatment, but prior studies in humans have not included continuous long-term stimulation or 3D binocular vestibulo-ocular reflex (VOR) oculography, without which one cannot determine whether an implant selectively stimulates the implanted ear's 3 semicircular canals.METHODSWe report binocular 3D VOR responses of 4 human subjects with ototoxic bilateral vestibular loss unilaterally implanted with a Labyrinth Devices Multichannel Vestibular Implant System vestibular implant, which provides continuous, long-term, motion-modulated prosthetic stimulation via electrodes in 3 semicircular canals.RESULTSInitiation of prosthetic stimulation evoked nystagmus that decayed within 30 minutes. Stimulation targeting 1 canal produced 3D VOR responses approximately aligned with that canal's anatomic axis. Targeting multiple canals yielded responses aligned with a vector sum of individual responses. Over 350-812 days of continuous 24 h/d use, modulated electrical stimulation produced stable VOR responses that grew with stimulus intensity and aligned approximately with any specified 3D head rotation axis.CONCLUSIONThese results demonstrate that a vestibular implant can selectively, continuously, and chronically provide artificial sensory input to all 3 implanted semicircular canals in individuals disabled by bilateral vestibular loss, driving reflexive VOR eye movements that approximately align in 3D with the head motion axis encoded by the implant.TRIAL REGISTRATIONClinicalTrials.gov: NCT02725463.FUNDINGNIH/National Institute on Deafness and Other Communication Disorders: R01DC013536 and 2T32DC000023; Labyrinth Devices, LLC; and Med-El GmbH.
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Affiliation(s)
| | - Desi P Schoo
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Mehdi Rahman
- Labyrinth Devices, LLC, Baltimore, Maryland, USA
| | | | | | | | | | | | | | | | | | - Gene Y Fridman
- Department of Biomedical Engineering and.,Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | | | - Bryan K Ward
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Carolina Treviño
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Stephen P Bowditch
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Dale C Roberts
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Kelly E Lane
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Yoav Gimmon
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Michael C Schubert
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - John P Carey
- Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | | | - Charles C Della Santina
- Department of Biomedical Engineering and.,Department of Otolaryngology - Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.,Labyrinth Devices, LLC, Baltimore, Maryland, USA
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Fornos AP, van de Berg R, Armand S, Cavuscens S, Ranieri M, Crétallaz C, Kingma H, Guyot JP, Guinand N. Cervical myogenic potentials and controlled postural responses elicited by a prototype vestibular implant. J Neurol 2019; 266:33-41. [PMID: 31396689 PMCID: PMC6722147 DOI: 10.1007/s00415-019-09491-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/28/2019] [Accepted: 07/29/2019] [Indexed: 02/04/2023]
Abstract
Gaze stabilization and postural control are two key functions of the vestibular system. In consequence, oscillopsia and chronic imbalance are the two main complaints of patients presenting with a severe bilateral vestibular function loss. The vestibular implant is emerging as a promising treatment for this group of patients whose quality of life is significantly impaired. Although the final aim of the vestibular implant should be to restore vestibular function as a whole, until now the research has focused mainly on the restoration of the vestibulo-ocular reflex to improve gaze stabilization. In this study, we aimed to explore whether the vestibulo-collic and vestibulo-spinal pathways could be activated and controlled with the electrical stimuli provided by our vestibular implant prototype. This was first explored and demonstrated with recordings of electrically elicited cervical vestibular evoked myogenic potentials (ecVEMPs). ecVEMPs with characteristics similar to the classical acoustically elicited cervical vestibular evoked myogenic potentials (cVEMPs) were successfully evoked in five out of the eight tested patients. Amplitudes of the electrically elicited N–P complex varied, ranging from 44 to 120 µV. Mean latencies of the N and P waves were of 9.71(± 1.17) ms and 17.24 ms (± 1.74), respectively. We also evaluated the possibility of generating controlled postural responses using a stepping test. Here, we showed that controlled and consistent whole-body postural responses can be effectively obtained with rapid changes in the “baseline” (constant rate and amplitude) electrical activity delivered by the vestibular implant in two out of the three tested subjects. Furthermore, obtained amplitude of body rotations was significantly correlated with the intensity of stimulation and direction of body rotations correlated with the side of the delivered stimulus (implanted side). Altogether, these data suggest that the vestibular implant could also be used to improve postural control in patients with bilateral vestibulopathy.
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Affiliation(s)
- Angelica Perez Fornos
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Raymond van de Berg
- Division of Balance Disorders, Department of ENT, Maastricht University Medical Centre, Maastricht, The Netherlands
- Faculty of Physics, Tomsk State University, Tomsk, Russia
| | - Stéphane Armand
- Willy Taillard Laboratory of Kinesiology, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Samuel Cavuscens
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Maurizio Ranieri
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Céline Crétallaz
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Herman Kingma
- Division of Balance Disorders, Department of ENT, Maastricht University Medical Centre, Maastricht, The Netherlands
- Faculty of Physics, Tomsk State University, Tomsk, Russia
| | - Jean-Philippe Guyot
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Nils Guinand
- Division of Otorhinolaryngology Head and Neck Surgery, Geneva University Hospitals and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland.
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Virtual Rhesus Labyrinth Model Predicts Responses to Electrical Stimulation Delivered by a Vestibular Prosthesis. J Assoc Res Otolaryngol 2019; 20:313-339. [PMID: 31165284 DOI: 10.1007/s10162-019-00725-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 05/08/2019] [Indexed: 10/26/2022] Open
Abstract
To better understand the spread of prosthetic current in the inner ear and to facilitate design of electrode arrays and stimulation protocols for a vestibular implant system intended to restore sensation after loss of vestibular hair cell function, we created a model of the primate labyrinth. Because the geometry of the implanted ear is complex, accurately modeling effects of prosthetic stimuli on vestibular afferent activity required a detailed representation of labyrinthine anatomy. Model geometry was therefore generated from three-dimensional (3D) reconstructions of a normal rhesus temporal bone imaged using micro-MRI and micro-CT. For systematically varied combinations of active and return electrode location, the extracellular potential field during a biphasic current pulse was computed using finite element methods. Potential field values served as inputs to stochastic, nonlinear dynamic models for each of 2415 vestibular afferent axons, each with unique origin on the neuroepithelium and spiking dynamics based on a modified Smith and Goldberg model. We tested the model by comparing predicted and actual 3D vestibulo-ocular reflex (VOR) responses for eye rotation elicited by prosthetic stimuli. The model was individualized for each implanted animal by placing model electrodes in the standard labyrinth geometry based on CT localization of actual implanted electrodes. Eye rotation 3D axes were predicted from relative proportions of model axons excited within each of the three ampullary nerves, and predictions were compared to archival eye movement response data measured in three alert rhesus monkeys using 3D scleral coil oculography. Multiple empirically observed features emerged as properties of the model, including effects of changing active and return electrode position. The model predicts improved prosthesis performance when the reference electrode is in the labyrinth's common crus (CC) rather than outside the temporal bone, especially if the reference electrode is inserted nearly to the junction of the CC with the vestibule. Extension of the model to human anatomy should facilitate optimal design of electrode arrays for clinical application.
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41
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Dlugaiczyk J, Gensberger KD, Straka H. Galvanic vestibular stimulation: from basic concepts to clinical applications. J Neurophysiol 2019; 121:2237-2255. [DOI: 10.1152/jn.00035.2019] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Galvanic vestibular stimulation (GVS) plays an important role in the quest to understand sensory signal processing in the vestibular system under normal and pathological conditions. It has become a highly relevant tool to probe neuronal computations and to assist in the differentiation and treatment of vestibular syndromes. Following its accidental discovery, GVS became a diagnostic tool that generates eye movements in the absence of head/body motion. With the possibility to record extracellular and intracellular spikes, GVS became an indispensable method to activate or block the discharge in vestibular nerve fibers by cathodal and anodal currents, respectively. Bernie Cohen, in his attempt to decipher vestibular signal processing, has used this method in a number of hallmark studies that have added to our present knowledge, such as the link between selective electrical stimulation of semicircular canal nerves and the generation of directionally corresponding eye movements. His achievements paved the way for other major milestones including the differential recruitment order of vestibular fibers for cathodal and anodal currents, pronounced discharge adaptation of irregularly firing afferents, potential activation of hair cells, and fiber type-specific activation of central circuits. Previous disputes about the structural substrate for GVS are resolved by integrating knowledge of ion channel-related response dynamics of afferents, fiber type-specific innervation patterns, and central convergence and integration of semicircular canal and otolith signals. On the basis of solid knowledge of the methodology, specific waveforms of GVS are currently used in clinical diagnosis and patient treatment, such as vestibular implants and noisy galvanic stimulation.
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Affiliation(s)
- Julia Dlugaiczyk
- German Center for Vertigo and Balance Disorders, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
- Department of Neurology, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Hans Straka
- Department Biology II, Ludwig-Maximilians-Universität München, Planegg, Germany
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Boutros PJ, Valentin NS, Hageman KN, Dai C, Roberts D, Della Santina CC. Nonhuman primate vestibuloocular reflex responses to prosthetic vestibular stimulation are robust to pulse timing errors caused by temporal discretization. J Neurophysiol 2019; 121:2256-2266. [PMID: 30995152 DOI: 10.1152/jn.00887.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Electrical stimulation of vestibular afferent neurons to partially restore semicircular canal sensation of head rotation and the stabilizing reflexes that sensation supports has potential to effectively treat individuals disabled by bilateral vestibular hypofunction. Ideally, a vestibular implant system using this approach would be integrated with a cochlear implant, which would provide clinicians with a means to simultaneously treat loss of both vestibular and auditory sensation. Despite obvious similarities, merging these technologies poses several challenges, including stimulus pulse timing errors that arise when a system must implement a pulse frequency modulation-encoding scheme (as is used in vestibular implants to mimic normal vestibular nerve encoding of head movement) within fixed-rate continuous interleaved sampling (CIS) strategies used in cochlear implants. Pulse timing errors caused by temporal discretization inherent to CIS create stair step discontinuities of the vestibular implant's smooth mapping of head velocity to stimulus pulse frequency. In this study, we assayed electrically evoked vestibuloocular reflex responses in two rhesus macaques using both a smooth pulse frequency modulation map and a discretized map corrupted by temporal errors typical of those arising in a combined cochlear-vestibular implant. Responses were measured using three-dimensional scleral coil oculography for prosthetic electrical stimuli representing sinusoidal head velocity waveforms that varied over 50-400°/s and 0.1-5 Hz. Pulse timing errors produced negligible effects on responses across all canals in both animals, indicating that temporal discretization inherent to implementing a pulse frequency modulation-coding scheme within a cochlear implant's CIS fixed pulse timing framework need not sacrifice performance of the combined system's vestibular implant portion. NEW & NOTEWORTHY Merging a vestibular implant system with existing cochlear implant technology can provide clinicians with a means to restore both vestibular and auditory sensation. Pulse timing errors inherent to integration of pulse frequency modulation vestibular stimulation with fixed-rate, continuous interleaved sampling cochlear implant stimulation would discretize the smooth head velocity encoding of a combined device. In this study, we show these pulse timing errors produce negligible effects on electrically evoked vestibulo-ocular reflex responses in two rhesus macaques.
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Affiliation(s)
- Peter J Boutros
- Department of Biomedical Engineering, Johns Hopkins School of Medicine , Baltimore, Maryland
| | - Nicolas S Valentin
- Department of Biomedical Engineering, Johns Hopkins School of Medicine , Baltimore, Maryland
| | - Kristin N Hageman
- Department of Biomedical Engineering, Johns Hopkins School of Medicine , Baltimore, Maryland
| | - Chenkai Dai
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine , Baltimore, Maryland
| | - Dale Roberts
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine , Baltimore, Maryland
| | - Charles C Della Santina
- Department of Biomedical Engineering, Johns Hopkins School of Medicine , Baltimore, Maryland.,Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine , Baltimore, Maryland
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