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Bancel T, Béranger B, Daniel M, Didier M, Santin M, Rachmilevitch I, Shapira Y, Tanter M, Bardinet E, Fernandez Vidal S, Attali D, Galléa C, Dizeux A, Vidailhet M, Lehéricy S, Grabli D, Pyatigorskaya N, Karachi C, Hainque E, Aubry JF. Sustained reduction of Essential Tremor with low-power non-thermal transcranial focused ultrasound stimulations in humans. Brain Stimul 2024:S1935-861X(24)00085-8. [PMID: 38734066 DOI: 10.1016/j.brs.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 05/03/2024] [Accepted: 05/03/2024] [Indexed: 05/13/2024] Open
Abstract
BACKGROUND Transcranial ultrasound stimulation (TUS) is a non-invasive brain stimulation technique; when skull aberrations are compensated for, this technique allows, with millimetric accuracy, circumvention of the invasive surgical procedure associated with deep brain stimulation (DBS) and the limited spatial specificity of transcranial magnetic stimulation. OBJECTIVE /hypothesis: We hypothesize that MR-guided low-power TUS can induce a sustained decrease of tremor power in patients suffering from medically refractive essential tremors. METHODS The dominant hand only was targeted, and two anatomical sites were sonicated in this exploratory study: the ventral intermediate nucleus of the thalamus (VIM) and the dentato-rubro-thalamic tract (DRT). Patients (N=9) were equipped with MR-compatible accelerometers attached to their hands to monitor their tremor in real-time during TUS. RESULTS VIM neurostimulations followed by a low-duty cycle (5%) DRT stimulation induced a substantial decrease in the tremor power in four patients, with a minimum of 89.9% reduction when compared with the baseline power a few minutes after the DRT stimulation. The only patient stimulated in the VIM only and with a low duty cycle (5%) also experienced a sustained reduction of the tremor (up to 93.4%). Four patients (N=4) did not respond. The temperature at target was 37.2 ± 1.4°C compared to 36.8 ± 1.4°C for a 3cm away control point. CONCLUSIONS MR-guided low power TUS can induce a substantial and sustained decrease of tremor power. Follow-up studies need to be conducted to reproduce the effect and better to understand the variability of the response amongst patients. MR thermometry during neurostimulations showed no significant thermal rise, supporting a mechanical effect.
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Affiliation(s)
- Thomas Bancel
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France
| | - Benoît Béranger
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Maxime Daniel
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France
| | - Mélanie Didier
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Mathieu Santin
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | | | | | - Mickael Tanter
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France
| | - Eric Bardinet
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Sara Fernandez Vidal
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - David Attali
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France
| | - Cécile Galléa
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France
| | - Alexandre Dizeux
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France
| | - Marie Vidailhet
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; Neurology Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Stéphane Lehéricy
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; Neuroradiology Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - David Grabli
- Neurology Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Nadya Pyatigorskaya
- Institut du Cerveau, ICM, Centre de NeuroImagerie de Recherche, CENIR, Inserm U 1127, CNRS UMR 7225, Sorbonne Université, F-75013 Paris, France; Neuroradiology Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Carine Karachi
- Neurosurgery Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Elodie Hainque
- Neurology Department, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Jean-François Aubry
- Physics for Medicine Paris, Inserm U1273, ESPCI Paris, CNRS UMR8361, PSL University, Paris, France.
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Miguel-Puga A, Villafuerte G, Treviño M, Ortega-Robles E, Arias-Carrión O. Effect of Propranolol on Motor Cortex Excitability in Essential Tremor: An Exploratory Study. Tremor Other Hyperkinet Mov (N Y) 2024; 14:1. [PMID: 38189055 PMCID: PMC10768567 DOI: 10.5334/tohm.829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 12/21/2023] [Indexed: 01/09/2024] Open
Abstract
Background Essential tremor, the world's most prevalent movement disorder, lacks a clear understanding of its pathophysiology. Propranolol, a non-specific beta-blocker capable of crossing the blood-brain barrier, is a primary choice for essential tremor treatment. While its tremor-reducing effects are generally attributed to peripheral actions, various uses hint at central adrenergic effects. Nevertheless, propranolol's precise impact on the central nervous system in essential tremor subjects remains unexplored. Methods In this study, we employed transcranial magnetic stimulation to assess the influence of propranolol on the excitability of the primary motor cortex (M1) in patients with essential tremor, compared to an age- and sex-matched control group. Cortical excitability parameters were measured following placebo and propranolol administration, encompassing resting and active motor thresholds, motor evoked potential characteristics, cortical silent period, and the input/output curve. Results Distinct effects were observed across the two cortical hemispheres. Essential tremor patients displayed inhibition of the left M1 cortex and heightened excitability in the right M1 cortex four hours after propranolol administration, but not following placebo. Conclusions These findings suggest potential differential noradrenergic excitatory and inhibitory modulation. However, comprehensive understanding necessitates further investigations, including left-handed participants and more diverse essential tremor subpopulations. This study underscores the need for continued exploration to unravel propranolol's complex effects on motor cortex excitability in essential tremor.
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Affiliation(s)
- Adán Miguel-Puga
- Unidad de Trastornos del Movimiento y Sueño (TMS), Hospital General Dr. Manuel Gea González. Ciudad de México, 14080 México, MX
| | - Gabriel Villafuerte
- Unidad de Trastornos del Movimiento y Sueño (TMS), Hospital General Dr. Manuel Gea González. Ciudad de México, 14080 México, MX
| | - Mario Treviño
- Laboratorio de Plasticidad Cortical y Aprendizaje Perceptual, Instituto de Neurociencias, Universidad de Guadalajara, Guadalajara, 44130 México, MX
| | - Emmanuel Ortega-Robles
- Unidad de Trastornos del Movimiento y Sueño (TMS), Hospital General Dr. Manuel Gea González. Ciudad de México, 14080 México, MX
| | - Oscar Arias-Carrión
- Unidad de Trastornos del Movimiento y Sueño (TMS), Hospital General Dr. Manuel Gea González. Ciudad de México, 14080 México, MX
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Lenka A, Louis ED. Developing a Staging Scheme for Essential Tremor: A Discussion of Organizing Principles. Tremor Other Hyperkinet Mov (N Y) 2023; 13:43. [PMID: 37954035 PMCID: PMC10637291 DOI: 10.5334/tohm.812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023] Open
Abstract
Essential tremor (ET) is a chronic, progressive neurological disease that may negatively affect patients' lives. While there has been considerable progress in ET research, some fundamental issues remain unaddressed. One such issue is disease staging. Staging schemes have inherent value and are part of the dialogue that clinicians have with other movement disorders patients. We highlight the value of and challenges with developing a staging system for ET and organize a discussion around the potential steps in developing such a system. Diseases for which there are staging schemes generally have a number of shared characteristics. ET has numerous features that would lend themselves to a staging scheme: emerging evidence supporting the existence of a premotor phase of disease, insidious onset, progressive worsening of arm tremor, spread of tremor to other body regions, the observation that patients seem to be at increased risk for other conditions within the same organ (i.e., emergence of Parkinson's disease and Alzheimer's disease in excessive numbers of ET patients), pathological changes in the cerebellum whose evolution can be ordered from (i) those that compromise the physical integrity and physiological function of Purkinje cells, (ii) subsequent changes that are reparative and regenerative, and (iii) eventual cell death. Challenges to formulating a staging scheme are the absence of both a biological marker and an "end stage" of disease. The sum of combined evidence suggests that a staging scheme would be of value. We provide initial thoughts as to how to begin to structure such a staging scheme.
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Affiliation(s)
- Abhishek Lenka
- Department of Neurology, Baylor College of Medicine, Houston, TX, USA
| | - Elan D Louis
- Department of Neurology, University of Texas Southwestern, Dallas, TX, USA
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Serrano-Dueñas M, Torres-Herrán G. Essential tremor and the scales: Quality of life in essential tremor, the Fahn-Tolosa-Marin Tremor Rating Scale; and, the Bain and Findley Clinical Tremor Rating Scale. Clin Neurol Neurosurg 2023; 226:107628. [PMID: 36805252 DOI: 10.1016/j.clineuro.2023.107628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/16/2023] [Accepted: 02/09/2023] [Indexed: 02/17/2023]
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Brinda A, Slopsema JP, Butler RD, Ikramuddin S, Beall T, Guo W, Chu C, Patriat R, Braun H, Goftari M, Palnitkar T, Aman J, Schrock L, Cooper SE, Matsumoto J, Vitek JL, Harel N, Johnson MD. Lateral cerebellothalamic tract activation underlies DBS therapy for Essential Tremor. Brain Stimul 2023; 16:445-55. [PMID: 36746367 DOI: 10.1016/j.brs.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 01/17/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND While deep brain stimulation (DBS) therapy can be effective at suppressing tremor in individuals with medication-refractory Essential Tremor, patient outcome variability remains a significant challenge across centers. Proximity of active electrodes to the cerebellothalamic tract (CTT) is likely important in suppressing tremor, but how tremor control and side effects relate to targeting parcellations within the CTT and other pathways in and around the ventral intermediate (VIM) nucleus of thalamus remain unclear. METHODS Using ultra-high field (7T) MRI, we developed high-dimensional, subject-specific pathway activation models for 23 directional DBS leads. Modeled pathway activations were compared with post-hoc analysis of clinician-optimized DBS settings, paresthesia thresholds, and dysarthria thresholds. Mixed-effect models were utilized to determine how the six parcellated regions of the CTT and how six other pathways in and around the VIM contributed to tremor suppression and induction of side effects. RESULTS The lateral portion of the CTT had the highest activation at clinical settings (p < 0.05) and a significant effect on tremor suppression (p < 0.001). Activation of the medial lemniscus and posterior-medial CTT was significantly associated with severity of paresthesias (p < 0.001). Activation of the anterior-medial CTT had a significant association with dysarthria (p < 0.05). CONCLUSIONS This study provides a detailed understanding of the fiber pathways responsible for therapy and side effects of DBS for Essential Tremor, and suggests a model-based programming approach will enable more selective activation of lateral fibers within the CTT.
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Skinner JW, Lee HK, Hass CJ. Evaluation of gait termination strategy in individuals with Essential Tremor and Parkinson's disease. Gait Posture 2022; 92:338-342. [PMID: 34920358 DOI: 10.1016/j.gaitpost.2021.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 11/23/2021] [Accepted: 12/07/2021] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Gait termination (GT) is a challenging transitory task involving converting from a dynamic state of motion to a static state. These transitional locomotor tasks are particularly troublesome for populations with postural deficits, i.e., Parkinson's disease (PD) and Essential Tremor (ET). They demand greater postural control and intricate integration of the neuromuscular system. The mechanisms involved in GT in these populations have not been well studied despite the safety concerns and potential risk for falls. The purpose of this investigation was to examine the different control strategies utilized during GT between individuals with ET and PD. METHODS Twenty-four individuals with ET (66 ± 8 yrs), twenty-four individuals with PD (64 ± 8 yrs), and twenty healthy older adults (HOA: 63 ± 9 yrs) participated in this study. Average self-selected gait velocity for each group was collected during the GT trial walking portion. Ground reaction force (GRF) data were used to calculate braking and propulsive forces from the last two steps during GT. GRF data measured the dynamic postural stability index (DPSI), defined as an individual's ability to maintain balance while transitioning from a dynamic to a stable state. RESULTS Persons with ET had a significantly slower approach velocity (0.63 m/s) when compared to HOA (0.92 m/s) and PD (0.77 m/s). Persons with PD had significantly slower approach velocity when compared to HOA. Examination of GRF data found that those with ET generated significantly smaller propulsive and braking forces (p < .05). Forces increased in those with PD and then even more in the HOA group. Postural stability analysis revealed that ET had significantly worse stability scores than PD and HOA (p < .05). CONCLUSION Individuals with PD and ET utilize different control strategies for planned GT, which suggests both the cerebellum and the basal ganglia play central yet potentially different roles in anticipatory control during self-directed activities.
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Affiliation(s)
- Jared W Skinner
- Department of Health and Exercise Science, Appalachian State University, Boone, NC, USA.
| | - Hyo Keun Lee
- Biomechanics Research Institute, Vector Bio, Inc., Seoul, South Korea
| | - Chris J Hass
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA; Center for Movement Disorders and Neurorestoration, Gainesville, FL, USA
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Bereau M, Tranchant C. [Abnormal movements]. Rev Prat 2022; 72:93-100. [PMID: 35258263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Affiliation(s)
- Matthieu Bereau
- Service de neurologie, électrophysiologie clinique, CHU de Besançon, Besançon, France
| | - Christine Tranchant
- Service de pathologie du mouvement, neurologie, CHU de Strasbourg, Hôpital de Hautepierre, Strasbourg, France
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Bienes GHAA, Zorzenon CPF, Alves ED, Tibana LAT, Borges V, Carrete H, Ferraz HB. Neuroimaging Assessment of Nigrosome 1 with a Multiecho Gre Magnetic Resonance Sequence in the Differentiation Between Parkinsons Disease from Essential Tremor and Healthy Individuals. Tremor Other Hyperkinet Mov (N Y) 2021; 11:17. [PMID: 34046247 DOI: 10.5334/tohm.604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background and purpose Parkinsonism is commonly seen in many clinical conditions, and the establishment of its etiology may take many years. The possible development of neuroprotective treatments for Parkinsons disease (PD) in the near future will require correct and early diagnosis. This study aims to analyze the accuracy of a low-cost MRI sequence to differentiate PD from patients with essential tremor (ET) and healthy control (HC) individuals. Material and methods We recruited 70 individuals with clinical diagnoses of PD (38 patients), ET (11 patients) and healthy volunteers (21 individuals), all of whom underwent 3T MRI multiecho GRE sequence. Two blinded neuroradiologists independently evaluated the presence or absence of nigrosome-1(N1). We considered the unilateral or bilateral absence of nigrosome 1 signal as indicative of PD. Results The absence of at least one N1 could differentiate with 98% accuracy patients with clinical established PD from healthy controls. The presence of both nigrosomes was 96% accurate as a sign to differentiate PD from ET patients. Conclusion The 3T MRI with multiecho GRE is a simple and universally available technique and it can be used as a good auxiliary tool to differentiate PD from ET patients and controls.
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Evidente VGH, Ponce FA, Evidente MH, Lambert M, Garrett R, Sugumaran M, Lott DG. Adductor Spasmodic Dysphonia Improves with Bilateral Thalamic Deep Brain Stimulation: Report of 3 Cases Done Asleep and Review of Literature. Tremor Other Hyperkinet Mov (N Y) 2020; 10:60. [PMID: 33505767 DOI: 10.5334/tohm.575] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Background: To date, there are only six published reports of adductor spasmodic dysphonia (SD) responding to awake thalamic deep brain stimulation (DBS). Methods: We retrospectively reviewed cases of Essential Tremor (ET) with SD that were seen in our center from 2012 to 2020. We further identified those that have undergone thalamic DBS, and had a blinded laryngologist rate first the audio voice recordings before and after DBS using the Unified Spasmodic Dysphonia Rating Scale (USDRS), and the video recordings last to rate the related movements and facial grimacing. Results: We identified three cases of adductor SD with ET that had undergone bilateral ventralis intermedius (VIM) DBS under general anesthesia. All patients noted improvement of their limb and voice tremor, as well as their SD post-DBS. Although improvement of tremor was observed even with initial programming in all three, improvement of SD was noted only upon reaching higher amplitudes or wider pulse widths. Blinded voice assessments showed improvement of USDRS scores post-DBS compared to pre-DBS, and with stimulator on compared to stimulator off. Discussion: We report the first three cases of SD responding favorably to bilateral VIM asleep DBS and summarize the nine cases so far of SD who have undergone thalamic DBS.
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Dowd H, Zdrodowska MA, Radler KH, Cersonsky TEK, Rao AK, Huey ED, Cosentino S, Louis ED. Prospective Longitudinal Study of Gait and Balance in a Cohort of Elderly Essential Tremor Patients. Front Neurol 2020; 11:581703. [PMID: 33304305 PMCID: PMC7691661 DOI: 10.3389/fneur.2020.581703] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 10/08/2020] [Indexed: 12/01/2022] Open
Abstract
Background: Essential tremor (ET) encompasses a variety of features, including tremor, cognitive dysfunction, and gait and balance impairments. Gait and balance impairments in ET are often mild, but they can be severe and are, in some cases, associated with functional sequelae in terms of increased fall risk and reduced balance confidence. Previous research on gait and balance in ET has been limited to cross-sectional comparisons. There have been no longitudinal studies or prospective studies. As such, our understanding of natural history and possible predictors of declines in ET-related gait and balance impairments is incomplete. Objectives: We (1) present natural history data on the change in gait and balance measures over time, (2) provide estimates of annual rate of change in each gait and balance metric, and (3) examine the relationship between baseline clinical predictors and changes in gait and balance over time. Methods: 149 ET participants (mean age 78.7 years), enrolled in a prospective, longitudinal, clinical-pathological study, underwent an extensive evaluation of cognition, tremor, and gait and balance at three distinct intervals performed every 18 months. Gait and balance measures included a combination of performance-based tests (e.g., tandem gait, tandem stance) and self-reported assessments (e.g., number of falls, use of a walking aid). Results: Between the baseline and final assessments, numerous balance and gait measures showed evidence of decline and annual rates of change were quantified for each. We examined the predictive utility of clinical variables at baseline for five gait and balance outcomes, with global cognition and executive function standing out as the most consistent predictors. Conclusions: We present a much-needed look into the course of disease for elderly patients with ET, focusing on changes observed in gait and balance and the predictors of these changes. These results also add another dimension to the relevance of cognitive impairment observed in ET; such impairment can now be viewed as predictive of poorer gait and balance over time in ET. These findings are a useful tool for clinicians, patients, and their families to better understand and plan for changing disease-features over time.
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Affiliation(s)
- Hollie Dowd
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Maria Anna Zdrodowska
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Keith H. Radler
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Tess E. K. Cersonsky
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Ashwini K. Rao
- Department of Rehabilitation and Regenerative Medicine (Program in Physical Therapy), Gertrude H. Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Edward D. Huey
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, United States
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Stephanie Cosentino
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, United States
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Elan D. Louis
- Department of Neurology, University of Texas Southwestern, Dallas, TX, United States
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Gagliardo C, Ragonese P, Iacopino GD, Salemi G, Midiri M, D'Amelio M. Transcranial magnetic resonance-guided focused ultrasound thalamotomy as a safe treatment option in multiple sclerosis patients with essential tremor. Neurol Sci 2021; 42:1139-43. [PMID: 33094429 DOI: 10.1007/s10072-020-04841-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 10/16/2020] [Indexed: 01/19/2023]
Abstract
Transcranial magnetic resonance-guided focused ultrasound is a recently introduced incisionless treating option for essential tremor and tremor-dominant idiopathic Parkinson disease. There is preliminary evidence that it may result in a promising effective treatment option for other movement disorders too. Here, we report on two patients with multiple sclerosis with medication refractory debilitating essential tremor comorbidity who successfully underwent unilateral Vim tcMRgFUS thalamotomy for tremor control. Patients' clinical condition and expanded disability status scale scores showed no changes during the 1-year follow-up period with no evidence of multiple sclerosis activity or progression.
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Wadhwa A, Schaefer S, Gerrard J, Deeb W, Okun MS, Patel A. Deep Brain Stimulation Target Selection in Co-Morbid Essential Tremor and Parkinson's Disease. Tremor Other Hyperkinet Mov (N Y) 2020; 10:17. [PMID: 32775031 PMCID: PMC7394224 DOI: 10.5334/tohm.62] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/07/2020] [Indexed: 11/20/2022] Open
Abstract
Clinical Vignette A 64-year-old man with essential tremor (ET) and Parkinson's disease (PD) presented with medically refractory, large amplitude, debilitating rest and action tremor in his extremities. Clinical Dilemma Ventral intermediate nucleus of the thalamus (VIM) deep brain stimulation (DBS) improves tremor in ET and PD but does not ameliorate bradykinesia and rigidity in PD. The comparative efficacy of subthalamic nucleus (STN) DBS in managing action ET tremor remains unclear. Clinical Solution Bilateral STN was selected as the DBS target. Moderate improvement in rest tremor and mild improvement in action tremor were noted following initial programming. Gap In Knowledge There are no head-to-head trials to guide DBS target selection in patients with both ET and PD. Current evidence is limited to a few small head-to-head trials that have demonstrated equivalent efficacy in tremor reduction in PD patients using VIM as DBS target and in ET patients using STN. Expert Commentary Due to limited evidence, DBS treatment of complex cases, such as combined Parkinson's disease and essential tremor, remains based on expert consensus at each institution. Further multi-approach efforts, using imaging, electrophysiologic, and animal data, will be needed to answer the identified gap in knowledge. Highlights There is limited evidence to guide deep brain target selection in patients with essential tremor and Parkinson's disease. We review existing literature and propose strategies to manage tremor in these patients.
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Affiliation(s)
- Anant Wadhwa
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, US
| | - Sara Schaefer
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, US
| | - Jason Gerrard
- Department of Neurosurgery, Yale School of Medicine, Yale University, New Haven, CT, US
| | - Wissam Deeb
- Fixel Center for Neurological Diseases, Program for Movement Disorders and Neurorestoration, Department of Neurology, University of Florida, Gainesville, FL, US
| | - Michael S. Okun
- Fixel Center for Neurological Diseases, Program for Movement Disorders and Neurorestoration, Department of Neurology, University of Florida, Gainesville, FL, US
| | - Amar Patel
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, US
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Finger ME, Madden LL, Haq IU, McLouth CJ, Siddiqui MS. Analysis of the prevalence and onset of dysphonia and dysphagia symptoms in movement disorders at an academic medical center. J Clin Neurosci 2019; 64:111-115. [PMID: 30948311 DOI: 10.1016/j.jocn.2019.03.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 03/23/2019] [Indexed: 12/22/2022]
Abstract
Voice and swallowing impairments are common in movement disorders, but their effect on patients' quality of life is not well known. This study was conducted to determine the onset and prevalence of patient-reported dysphonia and dysphagia symptoms in Parkinson's disease (PD), dystonia, Atypical Parkinsonian Syndromes (APS), and Essential Tremor (ET). Patients referred to a movement disorders clinic in a tertiary care academic medical center completed validated voice and swallowing specific Quality of Life (QOL) questionnaires: Voice Handicap Index-10 (VHI-10) and Eating Assessment Tool-10 (EAT-10). Patient demographics and clinical data were also collected. Two hundred and sixty-eight patients (males = 150, females = 118) completed the questionnaires (n was PD = 103, APS = 30, ET = 56, dystonia = 32, other = 47). Prevalence of patient-reported dysphagia symptoms was significantly higher in APS (63%) than PD (26%), ET (25%), and dystonia (31%). Prevalence of patient-reported dysphonia symptoms was significantly lower in ET (14%) compared to PD (34%) and APS (43%). Disease duration was shorter in PD and APS compared to ET and dystonia (p < 0.05) before reporting clinically significant dysphonia and dysphagia symptoms indicating an earlier onset of these symptoms. There were significant positive correlations between VHI-10 and EAT-10 scores and disease severity, as indicated by Unified Parkinson's Disease motor scores (p < 0.0001) and modified Fahn-Tolosa-Marin Tremor Rating sub-scores (p = 0.0013). Patient-reported dysphonia and dysphagia symptoms were present in one fourth of patients with PD, ET, dystonia, and almost two thirds in APS. Patient-reported QOL measures, such as VHI-10 and EAT-10, can help screen movement disorder patients for dysphonia and dysphagia symptoms.
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Affiliation(s)
- Mary E Finger
- Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC, USA; Department of Otolaryngology-Head and Neck Surgery, Wake Forest School of Medicine, Winston-Salem, NC, USA.
| | - Lyndsay L Madden
- Department of Otolaryngology-Head and Neck Surgery, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Ihtsham U Haq
- Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Christopher J McLouth
- Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Mustafa S Siddiqui
- Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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14
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Abstract
Tremor is the commonest involuntary movement. The differential diagnosis is wide, and can be challenging even for experienced neurologists. Nonetheless, many tremors have a benign etiology and clinical course and, in many cases, non-neurologists are able to clinically manage these situations. This manuscript approaches the different types of tremor, their diagnosis, main differential diagnoses, the desired clinical approach, and therapeutic options of the most important conditions in clinical practice.
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Affiliation(s)
- Vanessa Carvalho
- Serviço de Neurologia. Hospital de Pedro Hispano/ULS Matosinhos. Matosinhos. Portugal
| | - João Massano
- Unidade de Doenças do Movimento e Cirurgia Funcional. Serviço de Neurologia. Centro Hospitalar Universitário de São João. Porto. Departamento de Neurociências Clínicas e Saúde Mental. Faculdade de Medicina. Universidade do Porto. Porto. Portugal
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15
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Varghese J, Niewöhner S, Soto-Rey I, Schipmann-Miletić S, Warneke N, Warnecke T, Dugas M. A Smart Device System to Identify New Phenotypical Characteristics in Movement Disorders. Front Neurol 2019; 10:48. [PMID: 30761078 PMCID: PMC6363699 DOI: 10.3389/fneur.2019.00048] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/14/2019] [Indexed: 01/30/2023] Open
Abstract
Parkinson's disease and Essential Tremor are two of the most common movement disorders and are still associated with high rates of misdiagnosis. Collected data by technology-based objective measures (TOMs) has the potential to provide new promising and highly accurate movement data for a better understanding of phenotypical characteristics and diagnostic support. A technology-based system called Smart Device System (SDS) is going to be implemented for multi-modal high-resolution acceleration measurement of patients with PD or ET within a clinical setting. The 2-year prospective observational study is conducted to identify new phenotypical biomarkers and train an Artificial Intelligence System. The SDS is going to be integrated and tested within a 20-min assessment including smartphone-based questionnaires, two smartwatches at both wrists and tablet-based Archimedean spirals drawing for deeper tremor-analyses. The electronic questionnaires will cover data on medication, family history and non-motor symptoms. In this paper, we describe the steps for this novel technology-utilizing examination, the principal steps for data analyses and the targeted performances of the system. Future work considers integration with Deep Brain Stimulation, dissemination into further sites and patient's home setting as well as integration with further data sources as neuroimaging and biobanks. Study Registration ID on ClinicalTrials.gov: NCT03638479.
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Affiliation(s)
- Julian Varghese
- Institute of Medical Informatics, University of Münster, Münster, Germany
| | - Stephan Niewöhner
- Department of Information Systems, University of Münster, Münster, Germany
| | - Iñaki Soto-Rey
- Institute of Medical Informatics, University of Münster, Münster, Germany
| | | | - Nils Warneke
- Department of Neurosurgery, University Hospital Münster, Münster, Germany
| | - Tobias Warnecke
- Department of Neurology, University Hospital Münster, Münster, Germany
| | - Martin Dugas
- Institute of Medical Informatics, University of Münster, Münster, Germany
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16
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Vance NE, Ulanowski EA, Danzl MM. Yoga led by a physical therapist for individuals with Essential Tremor: An explorative pilot study. Complement Ther Clin Pract 2018; 34:17-22. [PMID: 30712723 DOI: 10.1016/j.ctcp.2018.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 10/03/2018] [Accepted: 10/18/2018] [Indexed: 11/16/2022]
Abstract
PURPOSE The purpose of this pilot study is to evaluate the outcomes for individuals with Essential Tremor (ET) who participate in a community-based yoga class, led by a neurologic physical therapist. METHODS Six subjects with ET completed an 8-week intervention consisting of weekly 1-h yoga classes (in the Vinyasa style) guided by an instructor (200-h registered yoga teacher, physical therapist, and neurological resident). RESULTS Five subjects demonstrated improvements on the Tremor Research Group Essential Tremor Rating Scale (mean 15.3%, range 8.3-34.7%). The mean improvement on the Fullerton Advanced Balance Scale was 10.8% (range 2.5-20%). Five subjects maintained pre-intervention anxiety levels ("very low") while one reported increased anxiety secondary to a non-study related factor. Minimal improvements were noted in the McGill Quality of Life Questionnaire. CONCLUSION This pilot study offers support for further examining the benefits of integration of yoga into an exercise program for individuals with ET and specific suggestions for future research are offered. There were no adverse events with participation in yoga.
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Affiliation(s)
- Natalie E Vance
- Cressman Rehabilitation, Norton Healthcare, Louisville, KY, USA.
| | - Elizabeth A Ulanowski
- Doctor of Physical Therapy Program, School of Movement and Rehabilitation Sciences, College of Health Professions, Bellarmine University, Louisville, KY, USA
| | - Megan M Danzl
- Doctor of Physical Therapy Program, School of Movement and Rehabilitation Sciences, College of Health Professions, Bellarmine University, Louisville, KY, USA
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17
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Schmouth JF, Houle G, Ambalavanan A, Leblond CS, Spiegelman D, Laurent SB, Bourassa CV, Panisset M, Chouinard S, Dupré N, Vilariño-Güell C, Rajput A, Dion PA, Rouleau GA. Absence of Mutation Enrichment for Genes Phylogenetically Conserved in the Olivocerebellar Motor Circuitry in a Cohort of Canadian Essential Tremor Cases. Mol Neurobiol 2019; 56:4317-21. [PMID: 30315477 DOI: 10.1007/s12035-018-1369-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 09/27/2018] [Indexed: 10/28/2022]
Abstract
Essential Tremor is a prevalent neurological disorder of unknown etiology. Studies suggest that genetic factors contribute to this pathology. To date, no causative mutations in a gene have been reproducibly reported. All three structures of the olivocerebellar motor circuitry have been linked to Essential Tremor. We postulated that genes enriched for their expression in the olivocerebellar circuitry would be more susceptible to harbor mutations in Essential Tremor patients. A list of 11 candidate genes, enriched for their expression in the olivocerebellar circuitry, was assessed for their variation spectrum and frequency in a cohort of Canadian Essential Tremor cases. Our results from this list of 11 candidate genes do not support an association for Essential Tremor in our cohort of Canadian cases. The heterogenic nature of ET and modest size of the cohort used in this study are two confounding factors that could explain these results.
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18
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Hughes A, Huang Y, Schwartz ML, Hynynen K. The reduction in treatment efficiency at high acoustic powers during MR-guided transcranial focused ultrasound thalamotomy for Essential Tremor. Med Phys 2018; 45:2925-2936. [PMID: 29758099 DOI: 10.1002/mp.12975] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 05/07/2018] [Accepted: 05/07/2018] [Indexed: 12/19/2022] Open
Abstract
PURPOSE To analyze clinical data indicating a reduction in the induced energy-temperature efficiency relationship during transcranial focused ultrasound (FUS) Essential Tremor (ET) thalamotomy treatments at higher acoustic powers, establish its relationship with the spatial distribution of the focal temperature elevation, and explore its cause. METHODS A retrospective observational study of patients (n = 19) treated between July 2015 and August 2016 for (ET) by FUS thalamotomy was performed. These data were analyzed to compare the relationships between the applied power, the applied energy, the resultant peak temperature achieved in the brain, and the dispersion of the focal volume. Full ethics approval was received and all patients provided signed informed consent forms before the initiation of the study. Computer simulations, animal experiments, and clinical system tests were performed to determine the effects of skull heating, changes in brain properties and transducer acoustic output, respectively. All animal procedures were approved by the Animal Care and Use Committee and conformed to the guidelines set out by the Canadian Council on Animal Care. MATLAB was used to perform statistical analysis. RESULTS The reduction in the energy efficiency relationship during treatment correlates with the increase in size of the focal volume at higher sonication powers. A linear relationship exists showing that a decrease in treatment efficiency correlates positively with an increase in the focal size over the course of treatment (P < 0.01), supporting the hypothesis of transient skull and tissue heating causing acoustic aberrations leading to a decrease in efficiency. Changes in thermal conductivity, perfusion, absorption rates in the brain, as well as ultrasound transducer acoustic output levels were found to have minimal effects on the observed reduction in efficiency. CONCLUSIONS The reduction in energy-temperature efficiency during high-power FUS treatments correlated with observed increases in the size of the focal volume and is likely caused by transient changes in the tissue and skull during heating.
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Affiliation(s)
- Alec Hughes
- Department of Medical Biophysics, University of Toronto, 101 College St, Room 15-701, Toronto, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Room C713, 2075 Bayview Ave, Toronto, Canada
| | - Yuexi Huang
- Physical Sciences Platform, Sunnybrook Research Institute, Room C713, 2075 Bayview Ave, Toronto, Canada
| | - Michael L Schwartz
- Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, Toronto, Canada
| | - Kullervo Hynynen
- Department of Medical Biophysics, University of Toronto, 101 College St, Room 15-701, Toronto, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Room C713, 2075 Bayview Ave, Toronto, Canada
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19
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Akbar U, Asaad WF. A Comprehensive Approach to Deep Brain Stimulation for Movement Disorders. R I Med J (2013) 2017; 100:30-33. [PMID: 28564666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Deep brain stimulation (DBS) is a well-established form of neuromodulation, used primarily for movement disorders such as Parkinson's disease (PD) and Essential Tremor (ET). The selection of patients who will benefit most from DBS depends on a team of clinicians from various disciplines, including neurology, neurosurgery, psychiatry, neuropsychology and rehabilitation specialists. The actual surgical procedure can take many forms. We apply a combination of multidisciplinary, team-based evaluations and intra-operative neurophysiology, test stimulation and imaging to optimize DBS therapy for individual patients. [Full article available at http://rimed.org/rimedicaljournal-2017-06.asp].
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Affiliation(s)
- Umer Akbar
- Assistant Professor of Neurology, Brown University Alpert Medical School and Movement Disorders Program, Department of Neurology, Rhode Island Hospital and Butler Hospital; member of the Norman Prince Neurosciences Institute of Lifespan
| | - Wael F Asaad
- Assistant Professor of Neurosurgery (& Neuroscience), Brown University Alpert Medical School and Director of Functional Neurosurgery, Rhode Island Hospital; member of the Norman Prince Neurosciences Institute of Lifespan
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20
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Schuhmayer N, Weber C, Kieler M, Voller B, Pirker W, Auff E, Haubenberger D. Task-dependent variability of Essential Tremor. Parkinsonism Relat Disord 2017; 41:79-85. [PMID: 28576604 DOI: 10.1016/j.parkreldis.2017.05.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 04/05/2017] [Accepted: 05/18/2017] [Indexed: 11/30/2022]
Abstract
INTRODUCTION In Essential Tremor (ET), tremor characteristics and the impairment caused by tremor may vary from task to task. A variability of tremor frequency between postural and kinetic tasks has been proposed in ET, suggesting either multiple central oscillating networks, or peripheral or proprioceptive feedback-mechanisms. This electrophysiological study aimed to assess tremor frequencies and amplitudes in tasks involving postural and kinetic tremor, and compare findings within and across tasks, to delineate physiological differences underlying individually affected manual tasks in ET. METHODS 40 ET patients were included in the study. Tremor was characterized clinically, as well as electrophysiologically using accelerometry and digitizing tablet tasks. Tremor amplitude measures and frequencies were extracted for tasks involving kinetic (digital spiral drawing, handwriting), as well as postural tremor. Tremor was compared between and within tasks. RESULTS Digital spiral tremor frequencies were significantly higher compared to postural tremor frequencies, as measured by accelerometry, with a mean difference of >2 Hz (p < 0.001). Within-task variability of repeated digital spirals revealed a significant amplitude reduction over time in both hands (p < 0.001), with an up to 32% reduction compared to the first spiral. CONCLUSION ET exhibited a frequency variability, which was dependent on activation condition, suggesting neurophysiologically distinct pathways between postural and kinetic tremor. The reduction of tremor amplitudes observed in repeated digital spiral drawing may be explained by a learning effect or adaptation, and should be considered as non-random factor of variability when using spirals in ET to assess effects of interventions.
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Affiliation(s)
- Nicole Schuhmayer
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Corinna Weber
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Markus Kieler
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Bernhard Voller
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Walter Pirker
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Eduard Auff
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria
| | - Dietrich Haubenberger
- Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria; Clinical Trials Unit, Office of the Clinical Director, NINDS Intramural Research Program, National Institutes of Health, 9000 Rockville Pike, Bldg 10, Rm 6-5700, Bethesda 20892, MD, USA.
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21
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Cagnan H, Brown P, Bourget D, Denison T. Inertial-Based Control System Concepts for the Treatment of Movement Disorders. Int Solid State Sens Actuators Microsyst Conf 2015; 18:70-73. [PMID: 31799064 DOI: 10.1109/transducers.2015.7180863] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This work provides a summary of the state-of-the-art in inertial-based adaptive stimulation strategies for treatment of movement disorders like Parkinson's disease and Essential Tremor. A review of recent technical and clinical neuroscience is provided to give a state-of-the-art overview. We then propose a closed-loop system concept using an accelerometer and a phase locked loop algorithm as a conceptual methodology for enhanced therapy systems. The remaining challenges to practical implementation are then briefly described.
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Affiliation(s)
- Hayriye Cagnan
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Peter Brown
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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22
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Abstract
The field of essential tremor (ET) genetics remains extremely challenging. The relative lack of progress in understanding the genetic etiology of ET, however, does not reflect the lack of a genetic contribution, but rather, the presence of substantial phenotypic and genotypic heterogeneity. A meticulous approach to phenotyping is important for genetic research in ET. The only tool for phenotyping is the clinical history and examination. There is currently no ET-specific serum or imaging biomarker or defining neuropathological feature (e.g., a protein aggregate specific to ET) that can be used for phenotyping, and there is considerable clinical overlap with other disorders such as Parkinson's disease (PD) and dystonia. These issues greatly complicate phenotyping; thus, in some studies, as many as 30-50% of cases labeled as "ET" have later been found to carry other diagnoses (e.g., dystonia, PD) rather than ET. A cursory approach to phenotyping (e.g., merely defining ET as an "action tremor") is likely a major issue in some family studies of ET, and this as well as lack of standardized phenotyping across studies and patient centers is likely to be a major contributor to the relative lack of success of genome wide association studies (GWAS). To dissect the genetic architecture of ET, whole genome sequencing (WGS) in carefully characterized and well-phenotyped discovery and replication datasets of large case-control and familial cohorts will likely be of value. This will allow specific hypotheses about the mode of inheritance and genetic architecture to be tested. There are a number of approaches that still remain unexplored in ET genetics, including the contribution of copy number variants (CNVs), 'uncommon' moderate effect alleles, 'rare' variant large effect alleles (including Mendelian and complex/polygenic modes of inheritance), de novo and gonadal mosaicism, epigenetic changes and non-coding variation. Using these approaches is likely to yield new ET genes.
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Affiliation(s)
- L N Clark
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, 650 West 168th Street, New York, NY, 10032, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, USA
| | - E D Louis
- Department of Neurology, Yale School of Medicine, Yale University, 800 Howard Ave # 2, New Haven, CT 06519, USA.
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23
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Oh ES, Kim JM, Kim YE, Yun JY, Kim JS, Kim SE, Lee SB, Lee JJ, Park JH, Kim TH, Kim KW, Jeon BS. The prevalence of essential tremor in elderly Koreans. J Korean Med Sci 2014; 29:1694-8. [PMID: 25469072 PMCID: PMC4248593 DOI: 10.3346/jkms.2014.29.12.1694] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 08/25/2014] [Indexed: 11/20/2022] Open
Abstract
Essential tremor (ET) is one of the most common movement disorders. The prevalence of ET varies substantially among studies. In Korea, there is no well-designed epidemiological study of the prevalence of ET. Thus, we investigated the prevalence of ET in a community in Korea. Standardized interviews and in-person neurological examinations were performed in a random sample of the elderly aged 65 yr or older. Next, movement specialists attempted to diagnose ET clinically. People who showed equivocal parkinsonian features underwent dopamine transporter imaging using [(123)I]-FP-CIT SPECT, to differentiate ET from parkinsonism. A total of 714 subjects participated in this population-based study. Twenty six of these subjects were diagnosed as having ET. The crude prevalence of ET was 3.64 per 100 persons. Age, gender, or education period were not different between the ET patients and the non-ET subjects. The prevalence of ET was slightly lower than those reported in previous studies. Further studies including more subjects are warranted.
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Affiliation(s)
- Eung Seok Oh
- Department of Neurology, Chungnam National University School of Medicine, Chungnam National University Hospital, Daejeon, Korea
| | - Jong-Min Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Young Eun Kim
- Department of Neurology, Hallym University College of Medicine, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Ji Young Yun
- Department of Neurology, Ewha Womans University Mokdong Hospital, Seoul, Korea
| | - Ji Seon Kim
- Department of Neurology, Chungbuk National University School of Medicine, Chungbuk National University Hospital, Cheongju, Korea
| | - Sang Eun Kim
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Korea
| | - Seok Bum Lee
- Department of Psychiatry, Dankook University College of Medicine, Dankook University Hospital, Cheonan, Korea
| | - Jung Jae Lee
- Department of Psychiatry, Dankook University College of Medicine, Dankook University Hospital, Cheonan, Korea
| | - Joon Hyuk Park
- Department of Psychiatry, Jeju National Universtiy School of Medicine, Jeju National University Hospital, Jeju, Korea
| | - Tae Hui Kim
- Department of Psychiatry, Yonsei University Wonju Severance Christian Hospital, Wonju, Korea
| | - Ki Woong Kim
- Department of Psychiatry, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Korea
| | - Beom S. Jeon
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
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24
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Fernandez KM, Roemmich RT, Stegemöller EL, Amano S, Thompson A, Okun MS, Hass CJ. Gait initiation impairments in both Essential Tremor and Parkinson's disease. Gait Posture 2013; 38:956-61. [PMID: 23726428 PMCID: PMC3778167 DOI: 10.1016/j.gaitpost.2013.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 04/25/2013] [Accepted: 05/01/2013] [Indexed: 02/02/2023]
Abstract
Gait initiation is a transitional task involving a voluntary shift from a static, stable position to a relatively less-stable state of locomotion. During gait initiation, anticipatory postural adjustments precede stepping in order to generate forward momentum while balance is maintained. While deficits in gait initiation are frequently reported for persons with Parkinson's disease, there is a paucity of information regarding gait initiation performance in persons with Essential Tremor. We investigated anticipatory postural adjustments and spatiotemporal characteristics of gait initiation in persons with Essential Tremor and compared them to persons with Parkinson's disease as well as age-matched neurologically healthy adults. Twenty-four persons with Essential Tremor, 31 persons with Parkinson's disease, and 38 age-matched controls participated. We compared anterior-posterior and mediolateral center of pressure movements and spatiotemporal stepping characteristics during gait initiation among the three groups using Mann-Whitney U-tests with Bonferroni corrections for multiple comparisons and one-way ANOVAs. Persons with Parkinson's disease demonstrated significantly reduced displacement and velocity of the center of pressure during early phases of anticipatory postural adjustments relative to controls. Displacement of the center of pressure was also reduced in persons with Essential Tremor, although at a later stage of the gait initiation process. Persons with Parkinson's disease and Essential Tremor demonstrated similar reductions in step length during gait initiation when compared to controls. Persons with Parkinson's disease and Essential Tremor exhibit different deficits in gait initiation when compared to healthy older adults. Therefore, this study provides further evidence differentiating motor control features in these movement disorders.
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Affiliation(s)
- Kristina M. Fernandez
- Department of Applied Physiology and Kinesiology,Center for Movement Disorders and Neurorestoration
| | - Ryan T. Roemmich
- Department of Applied Physiology and Kinesiology,Center for Movement Disorders and Neurorestoration
| | - Elizabeth L. Stegemöller
- Department of Applied Physiology and Kinesiology,Center for Movement Disorders and Neurorestoration,Department of Neurology
| | - Shinichi Amano
- Department of Applied Physiology and Kinesiology,Center for Movement Disorders and Neurorestoration
| | - Amanda Thompson
- Center for Movement Disorders and Neurorestoration,Department of Neurology
| | - Michael S. Okun
- Center for Movement Disorders and Neurorestoration,Department of Neurology
| | - Chris J. Hass
- Department of Applied Physiology and Kinesiology,Center for Movement Disorders and Neurorestoration
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25
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Benamer HT. Parkinsonism and tremor disorders. A clinical approach. Libyan J Med 2007; 2:66-72. [PMID: 21503256 PMCID: PMC3078276 DOI: 10.4167/061222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Differentiation of idiopathic Parkinson's disease from other causes of Parkinsonism, such as Multiple System Atrophy, Progressive Supranuclar Palsy and Vascular Parkinsonism can be difficult. Clinicopathological studies suggest that the clinical diagnosis of idiopathic Parkinson's disease is 76% reliable. Also, clinical differentiation of tremor prominent Parkinsonism from Essential Tremor or Drug induced Parkinsonism may be problematic, especially in the early stages of the disease. Since these disorders are obviously different in clinical progress, it is important for the clinician to address the patient's and family's concerns about prognosis from a firm diagnostic footing. In this article the clinical features of the common and important causes of Parkinsonism and tremor disorders are reviewed and a practical approach is suggested.
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Affiliation(s)
- Hani Ts Benamer
- New Cross Hospital, Wolverhampton and Queen Elizabeth Neuroscience Centre, University Hospital Birmingham, UK
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