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Gerbasi ME, Elble RJ, Jones E, Gillespie A, Jarvis J, Chertavian E, Smith Z, Nejati M, Shih LC. Associations Among Tremor Amplitude, Activities of Daily Living, and Quality of Life in Patients with Essential Tremor. Tremor Other Hyperkinet Mov (N Y) 2024; 14:22. [PMID: 38708124 PMCID: PMC11067966 DOI: 10.5334/tohm.877] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 04/16/2024] [Indexed: 05/07/2024] Open
Abstract
Background Essential tremor (ET) is a disabling syndrome consisting of tremor, primarily in the upper limbs. We assessed the correlation of The Essential Tremor Rating Assessment Scale (TETRAS) Performance Item 4 ratings of upper limb tremor with the TETRAS activities of daily living (ADL) subscale and with 2 quality of life (QoL) scales. Methods This noninterventional, cross-sectional, point-in-time survey of neurologists(n = 60), primary care physicians (n = 38), and their patients with ET (n = 1,003) used real-world data collected through the Adelphi ET Disease Specific Programme™. Physician-reported measures (TETRAS Performance Item 4 and TETRAS ADL total) and patient-reported QoL measures (generic EuroQol-5 Dimension 5 Level [EQ-5D-5 L] and ET-specific Quality of Life in Essential Tremor Questionnaire (QUEST)) were assessed with bivariate and multivariable analyses. Sensitivity analyses were also conducted. Results The bivariate association between TETRAS Performance Item 4 score and TETRAS ADL total score was high (Pearson r = 0.761, P < 0.001). The bivariate associations between TETRAS Performance Item 4 score and EQ-5D-5 L index score (r = -0.410, P < 0.001) and between TETRAS ADL total score and EQ-5D-5 L index score (r = -0.543, P < 0.001) were moderate. The bivariate associations between TETRAS Performance Item 4 score and QUEST total score (r = 0.457, P < 0.001), and between TETRAS ADL total score and QUEST total score (r = 0.630, P < 0.001) were also moderate. These associations were unaltered by the inclusion of covariates. Discussion This study showed that greater tremor severity (TETRAS Performance Item 4) was positively correlated with ADL impairment (TETRAS ADL) and negatively associated with QoL (EQ-5D-5 L and QUEST). TETRAS Performance Item 4 score is a robust predictor of TETRAS ADL total score, and TETRAS Performance Item 4 and TETRAS ADL total scores were robust predictors of the 2 QoL scales. The results demonstrate the value of TETRAS scores as valid endpoints for future clinical trials. Highlights This real-world study assessed TETRAS scores as predictors of impaired QoL in ET. TETRAS Performance Item 4 and ADL were associated with EQ-5D-5 L and QUEST. TETRAS scores may serve as valid endpoints for future clinical trials.
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Affiliation(s)
| | - Rodger J. Elble
- Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Eddie Jones
- Adelphi Real World, Adelphi Mill, Bollington, United Kingdom
| | | | | | | | | | | | - Ludy C. Shih
- Boston University School of Medicine, Boston, MA, USA
- Boston Medical Center, Boston, MA, USA
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Elble RJ, Ondo WG, Lyons KE, Qin M, Garafola S, Hersh B, Lieu T, Arkilo D, Chuang R, Bankole K, Pahwa R. A Randomized Phase 2 KINETIC Trial Evaluating SAGE-324/BIIB124 in Individuals with Essential Tremor. Mov Disord 2024; 39:733-738. [PMID: 38357797 DOI: 10.1002/mds.29731] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/18/2023] [Accepted: 01/10/2024] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND SAGE-324/BIIB124 is an investigational positive allosteric modulator of GABAA receptors. OBJECTIVE KINETIC (NCT04305275), a double-blind, randomized, placebo-controlled, phase 2 study, evaluated SAGE-324/BIIB124 in individuals with essential tremor (ET). METHODS Individuals aged 18 to 80 years were randomly assigned 1:1 to orally receive 60 mg of SAGE-324/BIIB124 or placebo once daily for 28 days. The primary endpoint was change from baseline in The Essential Tremor Rating Assessment Scale-Performance Subscale (TETRAS-PS) Item 4 (upper-limb tremor) at day 29 with SAGE-324/BIIB124 versus placebo. RESULTS Between May 2020 and February 2021, 69 U.S. participants were randomly assigned to receive SAGE-324/BIIB124 (n = 34) or placebo (n = 35). There was a significant reduction from baseline in TETRAS-PS Item 4 at day 29 with SAGE-324/BIIB124 versus placebo (least squares mean [standard error]: -2.31 [0.401] vs. -1.24 [0.349], P = 0.0491). The most common treatment-emergent adverse events included somnolence, dizziness, fatigue, and balance disorder. CONCLUSION These results support further development of SAGE-324/BIIB124 for potential ET treatment. © 2024 Sage Therapeutics, Inc and The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - William G Ondo
- Department of Neurology, Houston Methodist Hospital, Houston, Texas, USA
| | - Kelly E Lyons
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Min Qin
- Sage Therapeutics, Inc, Cambridge, Massachusetts, USA
| | | | | | | | | | | | - Kemi Bankole
- Sage Therapeutics, Inc, Cambridge, Massachusetts, USA
| | - Rajesh Pahwa
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, USA
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3
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Elble RJ, Ondo W. Tremor rating scales and laboratory tools for assessing tremor. J Neurol Sci 2022; 435:120202. [DOI: 10.1016/j.jns.2022.120202] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/08/2021] [Accepted: 02/17/2022] [Indexed: 12/29/2022]
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Deuschl G, Becktepe JS, Dirkx M, Haubenberger D, Hassan A, Helmich R, Muthuraman M, Panyakaew P, Schwingenschuh P, Zeuner KE, Elble RJ. The clinical and electrophysiological investigation of tremor. Clin Neurophysiol 2022; 136:93-129. [DOI: 10.1016/j.clinph.2022.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/05/2022] [Accepted: 01/07/2022] [Indexed: 01/18/2023]
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Vu JP, Cisneros E, Zhao J, Lee HY, Jankovic J, Factor SA, Goetz CG, Barbano RL, Perlmutter JS, Jinnah HA, Richardson SP, Stebbins GT, Elble RJ, Comella CL, Peterson DA. From null to midline: changes in head posture do not predictably change head tremor in cervical dystonia. Dystonia 2022; 1:10684. [PMID: 37101941 PMCID: PMC10128866 DOI: 10.3389/dyst.2022.10684] [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] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Introduction A common view is that head tremor (HT) in cervical dystonia (CD) decreases when the head assumes an unopposed dystonic posture and increases when the head is held at midline. However, this has not been examined with objective measures in a large, multicenter cohort. Methods For 80 participants with CD and HT, we analyzed videos from examination segments in which participants were instructed to 1) let their head drift to its most comfortable position (null point) and then 2) hold their head straight at midline. We used our previously developed Computational Motor Objective Rater (CMOR) to quantify changes in severity, amplitude, and frequency between the two postures. Results Although up to 9% of participants had exacerbated HT in midline, across the whole cohort, paired t-tests reveal no significant changes in overall severity (t = -0.23, p = 0.81), amplitude (t = -0.80, p = 0.43), and frequency (t = 1.48, p = 0.14) between the two postures. Conclusions When instructed to first let their head drift to its null point and then to hold their head straight at midline, most patient's changes in HT were below the thresholds one would expect from the sensitivity of clinical rating scales. Counter to common clinical impression, CMOR objectively showed that HT does not consistently increase at midline posture in comparison to the null posture.
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Affiliation(s)
- Jeanne P. Vu
- Computational Neurology Center, Institute for Neural Computation, University of California, San Diego, La Jolla, CA, USA
| | - Elizabeth Cisneros
- Computational Neurology Center, Institute for Neural Computation, University of California, San Diego, La Jolla, CA, USA
| | - Jerry Zhao
- Computational Neurology Center, Institute for Neural Computation, University of California, San Diego, La Jolla, CA, USA
| | - Ha Yeon Lee
- Computational Neurology Center, Institute for Neural Computation, University of California, San Diego, La Jolla, CA, USA
| | - Joseph Jankovic
- Parkinson’s Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX, USA
| | - Stewart A. Factor
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Christopher G. Goetz
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | | | - Joel S. Perlmutter
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
- Departments of Radiology, Neuroscience, Physical Therapy, and Occupational Therapy, Washington University School of Medicine, St. Louis, MO, USA
| | - Hyder A. Jinnah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
- Departments of Human Genetics and Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Sarah Pirio Richardson
- Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
- Neurology Service, New Mexico Veterans Affairs Health Care System, Albuquerque, NM, USA
| | - Glenn T. Stebbins
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Rodger J. Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Cynthia L. Comella
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - David A. Peterson
- Computational Neurology Center, Institute for Neural Computation, University of California, San Diego, La Jolla, CA, USA
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
- Name, address, telephone and email address of the corresponding author: David Peterson, CNL-S, Salk Institute for Biological Studies, 10010 N. Torrey Pines Rd, La Jolla, CA 92037, 858-334-3110, Fax number: N/A,
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Abstract
Essential tremor (ET) plus is a new tremor classification that was introduced in 2018 by a task force of the International Parkinson and Movement Disorder Society. Patients with ET plus meet the criteria for ET but have one or more additional systemic or neurologic signs of uncertain significance or relevance to tremor (“soft signs”). Soft signs are not sufficient to diagnose another tremor syndrome or movement disorder, and soft signs in ET plus are known to have poor interrater reliability and low diagnostic sensitivity and specificity. Therefore, the clinical significance of ET plus must be interpreted probabilistically when judging whether a patient is more likely to have ET or a combined tremor syndrome, such as dystonic tremor. Such a probabilistic interpretation is possible with Bayesian analysis. This review presents a Bayesian analysis of ET plus in patients suspected of having ET versus a dystonic tremor syndrome, which is the most common differential diagnosis in patients referred for ET. Bayesian analysis of soft signs provides an estimate of the probability that a patient with possible ET is more likely to have an alternative diagnosis. ET plus is a distinct tremor classification and should not be viewed as a subtype of ET. ET plus covers a more-comprehensive phenotyping of people with possible ET, and the clinical interpretation of ET plus is enhanced with Bayesian analysis of associated soft signs.
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Affiliation(s)
- Rodger J. Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
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Abstract
A task force of the International Parkinson and Movement Disorder Society (MDS) recently published a tremor classification scheme that is based on the nosologic principle of two primary axes for classifying an illness: clinical manifestations (Axis 1) and etiology (Axis 2). An Axis 1 clinical syndrome is a recurring group of clinical symptoms, signs (physical findings), and possibly laboratory results that suggests the presence of at least one underlying Axis 2 etiology. Syndromes must be defined and used consistently to be of value in finding specific etiologies and effective treatments. The MDS task force concluded that essential tremor is a common neurological syndrome that has never been defined consistently by clinicians and researchers. The MDS task force defined essential tremor as a syndrome of bilateral upper limb action tremor of at least 3 years duration, with or without tremor in other locations (e.g., head, voice, or lower limbs), in the absence of other neurological signs (e.g., dystonia, parkinsonism, myoclonus, ataxia, peripheral neuropathy, and cognitive impairment). Deviations from this definition should not be labeled as essential tremor. Patients with additional questionably-abnormal signs or with signs of uncertain relevance to tremor are classified as essential tremor plus. The MDS classification scheme encourages a thorough unbiased phenotyping of patients with tremor, with no assumptions of etiology, pathology, pathophysiology, or relationship to other neurological disorders. The etiologies, pathology, and clinical course of essential tremor are too heterogeneous for this syndrome to be viewed as a disease or a family of diseases.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, United States
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Merola A, Torres‐Russotto DR, Stebbins GT, Vizcarra JA, Shukla AW, Hassan A, Marsili L, Krauss JK, Elble RJ, Deuschl G, Espay AJ. Development and Validation of the Orthostatic Tremor Severity and Disability Scale (
OT
‐10). Mov Disord 2020; 35:1796-1801. [DOI: 10.1002/mds.28142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 12/19/2022] Open
Affiliation(s)
- Aristide Merola
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio USA
| | | | - Glenn T. Stebbins
- Department of Neurological Sciences Rush University Medical Center Chicago Illinois USA
| | - Joaquin A. Vizcarra
- Department of Neurology Emory University Atlanta Georgia USA
- Gardner Family Center for Parkinson's Disease and Movement Disorders, Department of Neurology University of Cincinnati Cincinnati Ohio USA
| | - Aparna Wagle Shukla
- Department of Neurology University of Florida College of Medicine Gainesville Florida USA
| | - Anhar Hassan
- Department of Neurology Mayo Clinic Rochester Minnesota USA
| | - Luca Marsili
- Gardner Family Center for Parkinson's Disease and Movement Disorders, Department of Neurology University of Cincinnati Cincinnati Ohio USA
| | - Joachim K. Krauss
- Department of Neurosurgery Hannover Medical School, MHH Hannover Germany
| | - Rodger J. Elble
- Department of Neurology Southern Illinois University School of Medicine Springfield Illinois USA
| | - Günther Deuschl
- Department of Neurology Universitätsklinikum Schleswig‐Holstein, Christian‐Albrechts University Kiel Germany
| | - Alberto J. Espay
- Gardner Family Center for Parkinson's Disease and Movement Disorders, Department of Neurology University of Cincinnati Cincinnati Ohio USA
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Handforth A, Tse W, Elble RJ. A Pilot Double-Blind Randomized Trial of Perampanel for Essential Tremor. Mov Disord Clin Pract 2020; 7:399-404. [PMID: 32373656 DOI: 10.1002/mdc3.12927] [Citation(s) in RCA: 8] [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] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 01/25/2020] [Accepted: 02/10/2020] [Indexed: 11/10/2022] Open
Abstract
Background Perampanel is a noncompetitive antagonist of alpha-amino-3-hydroxy-5-methylisoxazole propionic acid glutamate receptors suggested to modulate tremor. Objectives To assess the efficacy and tolerability of perampanel for essential tremor. Methods This was a double-blind, placebo-controlled, randomized, cross-over trial involving 26 patients titrated to 8 mg/day or a lower maximally tolerated dose as monotherapy or adjunct to antitremor medication. Tremor was assessed at the beginning and end of each 14-week treatment arm. The primary endpoint was change in the videotaped performance subscale of The Essential Tremor Rating Assessment Scale, scored by a blinded rater. Secondary endpoints included change in The Essential Tremor Rating Assessment Scale Activity of Daily Living and Quality of Life in Essential Tremor and Subject Global Impression of Change subscales. Results Data are available for 15 and 11 participants who completed placebo and perampanel arms, respectively. Perampanel was superior to placebo on the primary endpoint (P = 0.028), Activity of Daily Living (P = 0.009), and Subject Global Impression of Change (P = 0.016), but not Quality of Life (p = 0.48). Video scores were rated >50% improved in 3/11 on perampanel and 0/15 on placebo. Adverse events were more likely on perampanel (especially at >4 mg/day) than on placebo, leading to withdrawal (36% vs. 10%) and dose reduction (41% vs. 15%). Adverse events more common with perampanel included imbalance/falls (50% vs. 10%), dizziness (36% vs. 10%), and irritability (27% vs. 5%). Conclusions These findings suggest that perampanel exerts efficacy for some persons with essential tremor, but this population appears prone to adverse events.
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Affiliation(s)
- Adrian Handforth
- Neurology Service, Veterans Affairs Greater Los Angeles Healthcare System Los Angeles California USA
| | - Winona Tse
- Department of Neurology, Movement Disorders Division Icahn School of Medicine at Mount Sinai New York New York USA
| | - Rodger J Elble
- Department of Neurology Southern Illinois University School of Medicine Springfield Illinois USA
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Kattah JC, Elble RJ, De Santo J, Shaikh AG. Oculopalatal tremor following sequential medullary infarcts that did not cause hypertrophic olivary degeneration. Cerebellum Ataxias 2020; 7:3. [PMID: 32082592 PMCID: PMC7023690 DOI: 10.1186/s40673-020-00112-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/07/2020] [Indexed: 11/28/2022]
Abstract
Background The syndrome of oculopalatal tremor is a known consequence of lesions in the dentate-olivary pathway. Hypertrophic degeneration of the inferior olive is a recognized pathological correlate of these lesions and hypothesized to cause tremorogenic olivary hypersynchrony. However, oculopalatal tremor also occurs in Alexander disease, which produces severe inferior olive degeneration without intervening hypertrophy. Methods Serial clinical, imaging, video-oculography and kinematic tremor recording of a patient with oculopalatal and limb tremor. Case study We report an unusual presentation of oculopalatal tremor and right upper extremity myorhythmia following sequential right dorsolateral and left anteromedial medullary infarcts directly involving both inferior olives. As in adult Alexander disease, our patient did not have hypertrophic olivary degeneration during 10 years of follow-up. Conclusion Contemporary theories have emphasized the role of cerebellar maladaptation in “shaping” oscillations generated elsewhere, the inferior olive in particular. Our patient and published Alexander disease cases illustrate that oculopalatal tremor can occur in the absence of hypertrophic olivary degeneration. Therefore, cerebellar maladaptation to any form of olivary damage may be the critical pathophysiology in producing oculopalatal tremor.
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Affiliation(s)
- Jorge C Kattah
- 1University of Illinois College of Medicicne, Peoria, Illinois USA
| | | | - Jeffrey De Santo
- 3University of Illinois, College of Medicine, Peoria, Illinois USA
| | - Aasef G Shaikh
- 4University Hospitals, Louis Stoke Cleveland Medecial Centter, Case Western Reserve, Cleveland, USA
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Kuo SH, Louis ED, Faust PL, Handforth A, Chang SY, Avlar B, Lang EJ, Pan MK, Miterko LN, Brown AM, Sillitoe RV, Anderson CJ, Pulst SM, Gallagher MJ, Lyman KA, Chetkovich DM, Clark LN, Tio M, Tan EK, Elble RJ. Current Opinions and Consensus for Studying Tremor in Animal Models. Cerebellum 2019; 18:1036-1063. [PMID: 31124049 PMCID: PMC6872927 DOI: 10.1007/s12311-019-01037-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tremor is the most common movement disorder; however, we are just beginning to understand the brain circuitry that generates tremor. Various neuroimaging, neuropathological, and physiological studies in human tremor disorders have been performed to further our knowledge of tremor. But, the causal relationship between these observations and tremor is usually difficult to establish and detailed mechanisms are not sufficiently studied. To overcome these obstacles, animal models can provide an important means to look into human tremor disorders. In this manuscript, we will discuss the use of different species of animals (mice, rats, fruit flies, pigs, and monkeys) to model human tremor disorders. Several ways to manipulate the brain circuitry and physiology in these animal models (pharmacology, genetics, and lesioning) will also be discussed. Finally, we will discuss how these animal models can help us to gain knowledge of the pathophysiology of human tremor disorders, which could serve as a platform towards developing novel therapies for tremor.
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Affiliation(s)
- Sheng-Han Kuo
- Department of Neurology, Columbia University, 650 West 168th Street, Room 305, New York, NY, 10032, USA.
| | - Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, 800 Howard Avenue, Ste Lower Level, New Haven, CT, 06519, USA.
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA.
- Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA.
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Medical Center and the New York Presbyterian Hospital, New York, NY, USA
| | - Adrian Handforth
- Neurology Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Su-Youne Chang
- Department of Neurologic Surgery and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Billur Avlar
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
| | - Eric J Lang
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
| | - Ming-Kai Pan
- Department of Medical Research and Neurology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Lauren N Miterko
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
| | - Amanda M Brown
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA
- Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, TX, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Collin J Anderson
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | | | - Kyle A Lyman
- Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Lorraine N Clark
- Department of Pathology and Cell Biology, Columbia University Medical Center and the New York Presbyterian Hospital, New York, NY, USA
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Murni Tio
- Department of Neurology, National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
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Torres-Russotto D, Elble RJ. Slow Orthostatic Tremor and the Case for Routine Electrophysiological Evaluation of All Tremors. Tremor Other Hyperkinet Mov (N Y) 2019; 9:tre-09-740. [PMID: 31832264 PMCID: PMC6886495 DOI: 10.7916/tohm.v0.740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 10/23/2019] [Indexed: 12/01/2022] Open
Affiliation(s)
- Diego Torres-Russotto
- Movement Disorders Division, Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| | - Rodger J. Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
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Elble RJ. Estimating Change in Tremor Amplitude Using Clinical Ratings: Recommendations for Clinical Trials. Tremor Other Hyperkinet Mov (N Y) 2019; 8:600. [PMID: 31637097 PMCID: PMC6802602 DOI: 10.7916/d89c8f3c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 09/17/2018] [Indexed: 12/01/2022]
Abstract
Tremor rating scales are the standard method for assessing tremor severity and clinical change due to treatment or disease progression. However, ratings and their changes are difficult to interpret without knowing the relationship between ratings and tremor amplitude (displacement or angular rotation), and the computation of percentage change in ratings relative to baseline is misleading because of the ordinal nature of these scales. For example, a reduction in tremor from rating 2 to rating 1 (0-4 scale) should not be interpreted as a 50% reduction in tremor amplitude, nor should a reduction in rating 4 to rating 3 be interpreted as a 25% reduction in tremor. Studies from several laboratories have found a logarithmic relationship between tremor ratings R and tremor amplitude T, measured with a motion transducer: logT = α·R + β, where α ≈ 0.5, β ≈ -2, and log is base 10. This relationship is consistent with the Weber-Fechner law of psychophysics, and from this equation, the fractional change in tremor amplitude for a given change in clinical ratings is derived: (Tf-Ti)/Ti=10α(Rf-(Ri)-1, where the subscripts i and f refer to the initial and final values. For a 0-4 scale and α = 0.5, a 1-point reduction in tremor ratings is roughly a 68% reduction in tremor amplitude, regardless of the baseline tremor rating (e.g., 2 or 4). Similarly, a 2-point reduction is roughly a 90% reduction in tremor amplitude. These Weber-Fechner equations should be used in clinical trials for computing and interpreting change in tremor, assessed with clinical ratings.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA.,Yale University, USA
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Abstract
INTRODUCTION Essential tremor is the most common form of pathologic tremor. Surgical therapies disrupt tremorogenic oscillation in the cerebellothalamocortical pathway and are capable of abolishing severe tremor that is refractory to available pharmacotherapies. Surgical methods are raspidly improving and are the subject of this review. Areas covered: A PubMed search on 18 January 2018 using the query essential tremor AND surgery produced 839 abstracts. 379 papers were selected for review of the methods, efficacy, safety and expense of stereotactic deep brain stimulation (DBS), stereotactic radiosurgery (SRS), focused ultrasound (FUS) ablation, and radiofrequency ablation of the cerebellothalamocortical pathway. Expert commentary: DBS and SRS, FUS and radiofrequency ablations are capable of reducing upper extremity tremor by more than 80% and are far more effective than any available drug. The main research questions at this time are: 1) the relative safety, efficacy, and expense of DBS, SRS, and FUS performed unilaterally and bilaterally; 2) the relative safety and efficacy of thalamic versus subthalamic targeting; 3) the relative safety and efficacy of atlas-based versus direct imaging tractography-based anatomical targeting; and 4) the need for intraoperative microelectrode recordings and macroelectrode stimulation in awake patients to identify the optimum anatomical target. Randomized controlled trials are needed.
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Affiliation(s)
- Rodger J Elble
- a Neuroscience Institute , Southern Illinois University School of Medicine , Springfield , Illinois , USA
| | - Ludy Shih
- b Department of Neurology , Beth Israel Deaconess Medical Center, Harvard Medical School , Boston , Massachusetts USA
| | - Jeffrey W Cozzens
- a Neuroscience Institute , Southern Illinois University School of Medicine , Springfield , Illinois , USA
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Bhatia KP, Bain P, Bajaj N, Elble RJ, Hallett M, Louis ED, Raethjen J, Stamelou M, Testa CM, Deuschl G. Consensus Statement on the classification of tremors. from the task force on tremor of the International Parkinson and Movement Disorder Society. Mov Disord 2018; 33:75-87. [PMID: 29193359 PMCID: PMC6530552 DOI: 10.1002/mds.27121] [Citation(s) in RCA: 737] [Impact Index Per Article: 122.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 05/03/2017] [Accepted: 06/04/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Consensus criteria for classifying tremor disorders were published by the International Parkinson and Movement Disorder Society in 1998. Subsequent advances with regard to essential tremor, tremor associated with dystonia, and other monosymptomatic and indeterminate tremors make a significant revision necessary. OBJECTIVES Convene an international panel of experienced investigators to review the definition and classification of tremor. METHODS Computerized MEDLINE searches in January 2013 and 2015 were conducted using a combination of text words and MeSH terms: "tremor", "tremor disorders", "essential tremor", "dystonic tremor", and "classification" limited to human studies. Agreement was obtained using consensus development methodology during four in-person meetings, two teleconferences, and numerous manuscript reviews. RESULTS Tremor is defined as an involuntary, rhythmic, oscillatory movement of a body part and is classified along two axes: Axis 1-clinical characteristics, including historical features (age at onset, family history, and temporal evolution), tremor characteristics (body distribution, activation condition), associated signs (systemic, neurological), and laboratory tests (electrophysiology, imaging); and Axis 2-etiology (acquired, genetic, or idiopathic). Tremor syndromes, consisting of either isolated tremor or tremor combined with other clinical features, are defined within Axis 1. This classification scheme retains the currently accepted tremor syndromes, including essential tremor, and provides a framework for defining new syndromes. CONCLUSIONS This approach should be particularly useful in elucidating isolated tremor syndromes and syndromes consisting of tremor and other signs of uncertain significance. Consistently defined Axis 1 syndromes are needed to facilitate the elucidation of specific etiologies in Axis 2. © 2017 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Kailash P. Bhatia
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, United Kingdom
| | - Peter Bain
- Department of Neurosciences, Charing Cross Hospital, Imperial College London, United Kingdom
| | - Nin Bajaj
- Division of Neurology, Nottingham University Hospital, Nottingham, United Kingdom
| | - Rodger J. Elble
- Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Elan D. Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut, USA, and Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, Connecticut, USA
| | - Jan Raethjen
- Department of Neurology, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Christian Albrechts University Kiel, Kiel, Germany
| | - Maria Stamelou
- Department of Neurology, Philipps University, Marburg, Germany; Department of Neurology, Attikon Hospital, University of Athens, Athens, Greece
| | | | - Guenther Deuschl
- Department of Neurology, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Christian Albrechts University Kiel, Kiel, Germany
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Abstract
Background Pure akinesia with gait freezing is a rare syndrome with few autopsied cases. Severe freezing of gait occurs in the absence of bradykinesia and rigidity. Most autopsies have revealed progressive supranuclear palsy. We report the clinical and postmortem findings of two patients with pure akinesia with gait freezing, provide video recordings of these patients, and review the literature describing similar cases. We also discuss bradykinesia, hypokinesia and akinesia in the context of this clinical syndrome. Case presentation Two patients with the syndrome of pure akinesia with gait freezing were examined by the same movement disorder specialist at least annually for 9 and 18 years. Both patients initially exhibited freezing, tachyphemia, micrographia and festination without bradykinesia and rigidity. Both autopsies revealed characteristic tau pathology of progressive supranuclear palsy, with nearly total neuronal loss and gliosis in the subthalamus and severe neuronal loss and gliosis in the globus pallidus and substantia nigra. Previously published postmortem studies revealed that most patients with this syndrome had progressive supranuclear palsy or pallidonigroluysian atrophy. Conclusions Pallidonigroluysian degeneration produces freezing and festination in the absence of generalized slowing (bradykinesia). Freezing and festination are commonly regarded as features of akinesia. Akinesia literally means absence of movement, and akinesia is commonly viewed as an extreme of bradykinesia. The pure akinesia with gait freezing phenotype illustrates that bradykinesia and akinesia should be viewed as separate phenomena. Electronic supplementary material The online version of this article (doi:10.1186/s40734-017-0063-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ahmad Elkouzi
- Department of Neurology, Southern Illinois University School of Medicine, PO Box 19645, Springfield, IL 62794-9645 USA
| | - Esther N Bit-Ivan
- Department of Neurology, Southern Illinois University School of Medicine, PO Box 19645, Springfield, IL 62794-9645 USA.,Department of Pathology, Southern Illinois University School of Medicine and Memorial Medical Center, Springfield, IL USA
| | - Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, PO Box 19645, Springfield, IL 62794-9645 USA
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Elble RJ, Ellenbogen A. Digitizing Tablet and Fahn-Tolosa-Marín Ratings of Archimedes Spirals have Comparable Minimum Detectable Change in Essential Tremor. Tremor Other Hyperkinet Mov (N Y) 2017; 7:481. [PMID: 28966878 PMCID: PMC5618112 DOI: 10.7916/d89s20h7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 06/20/2017] [Indexed: 12/01/2022]
Abstract
BACKGROUND Drawing Archimedes spirals is a popular and valid method of assessing action tremor in the upper limbs. We performed the first blinded comparison of Fahn-Tolosa-Marín (FTM) ratings and tablet measures of essential tremor to determine if a digitizing tablet is better than 0-4 ratings in detecting changes in essential tremor that exceed random variability in tremor amplitude. METHODS The large and small spirals of FTM were drawn with each hand on two consecutive days by 14 men and four women (age 60±8.7 years [mean±SD]) with mild to severe essential tremor. The drawings were simultaneously digitized with a digitizing tablet. Tremor in each digitized drawing was computed with spectral analysis in an independent laboratory, blinded to the clinical ratings. The mean peak-to-peak tremor displacement (cm) in the four spirals and mean FTM ratings were compared statistically. RESULTS Test-retest intraclass correlations (ICCs) (two-way random single measures, absolute agreement) were excellent for the FTM ratings (ICC 0.90, 95% CI 0.76-0.96) and tablet (ICC 0.97, 95% CI 0.91-0.99). Log10 tremor amplitude (T) and FTM were strongly correlated (logT=αFTM + β, α≈0.6, β≈-1.27, r=0.94). The minimum detectable change for the tablet and FTM were 51% and 67% of the initial assessment. DISCUSSION Digitizing tablets are much more precise than clinical ratings, but this advantage is mitigated by the natural variability in tremor. Nevertheless, the digitizing tablet is a robust method of quantifying tremor that can be used in lieu of or in combination with clinical ratings.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Aaron Ellenbogen
- Michigan Institute for Neurological Disorders, Farmington Hills, MI, USA
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Affiliation(s)
- Rodger J Elble
- Department of Neurology Southern Illinois University School of Medicine Springfield Illinois
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Affiliation(s)
- Alex P Michael
- From the Department of Surgery, Division of Neurosurgery (A.P.M.), and Department of Neurology (A.E., R.J.E.), Southern Illinois University School of Medicine, Springfield.
| | - Ahmad Elkouzi
- From the Department of Surgery, Division of Neurosurgery (A.P.M.), and Department of Neurology (A.E., R.J.E.), Southern Illinois University School of Medicine, Springfield
| | - Rodger J Elble
- From the Department of Surgery, Division of Neurosurgery (A.P.M.), and Department of Neurology (A.E., R.J.E.), Southern Illinois University School of Medicine, Springfield
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Elble RJ, Hellriegel H, Raethjen J, Deuschl G. Assessment of Head Tremor with Accelerometers Versus Gyroscopic Transducers. Mov Disord Clin Pract 2016; 4:205-211. [PMID: 30363428 DOI: 10.1002/mdc3.12379] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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: 01/20/2016] [Revised: 03/30/2016] [Accepted: 04/22/2016] [Indexed: 11/07/2022] Open
Abstract
Background Accelerometers and gyroscopes are used commonly in the assessment of hand tremor, but their validity in the assessment of head tremor has not been studied. We hypothesized that gyroscopy would be superior to accelerometry because head tremor is rotational motion, and gyroscopes record rotational motion, free of gravitational artifact. We also hypothesized a strong logarithmic relationship between 0 to 4-point tremor ratings and the transducer measures of tremor amplitude, similar to those previously reported for hand tremor. Methods Head tremor was recorded for 1 minute in each of the five head positions used in the Essential Tremor Rating Assessment Scale, using a triaxial accelerometer and triaxial gyroscope mounted at the vertex of the head. Mean and maximum 3-second burst displacement tremor and rotation tremor were computed by spectral analysis. The minimum detectable change for the transducers was estimated using the residual mean squared error from repeated-measures analysis of variance. Results Tremor displacement and rotation (T) were logarithmically related to tremor ratings (tremor rating score; TRS): log(T) = α TRS + β, where α ≈ 0.47 for displacement and ≈0.64 for rotation, and β ≈ -1.8 and -1.4. Tremor ratings correlated more strongly with gyroscopy (r = 0.83-0.87) than with accelerometry (r = 0.71-0.75). Minimum detectable change (percent reduction) was approximately 66% of the baseline geometric mean. Conclusions Gyroscopic transducers are superior to accelerometry for assessment of head tremor. Both measures of head tremor are logarithmically related to tremor ratings. The minimum detectable change of the transducer measures is comparable to those previously reported for hand tremor.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology Southern Illinois University School of Medicine Springfield Illinois USA.,Department of Neurology Christian-Albrechts-University Kiel Germany
| | - Helge Hellriegel
- Department of Neurology Christian-Albrechts-University Kiel Germany
| | - Jan Raethjen
- Department of Neurology Christian-Albrechts-University Kiel Germany
| | - Günther Deuschl
- Department of Neurology Christian-Albrechts-University Kiel Germany
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Haubenberger D, Abbruzzese G, Bain PG, Bajaj N, Benito-León J, Bhatia KP, Deuschl G, Forjaz MJ, Hallett M, Louis ED, Lyons KE, Mestre TA, Raethjen J, Stamelou M, Tan EK, Testa CM, Elble RJ. Transducer-based evaluation of tremor. Mov Disord 2016; 31:1327-36. [PMID: 27273470 DOI: 10.1002/mds.26671] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [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: 11/03/2015] [Revised: 04/04/2016] [Accepted: 04/07/2016] [Indexed: 11/11/2022] Open
Abstract
The International Parkinson and Movement Disorder Society established a task force on tremor that reviewed the use of transducer-based measures in the quantification and characterization of tremor. Studies of accelerometry, electromyography, activity monitoring, gyroscopy, digitizing tablet-based measures, vocal acoustic analysis, and several other transducer-based methods were identified by searching PubMed.gov. The availability, use, acceptability, reliability, validity, and responsiveness were reviewed for each measure using the following criteria: (1) used in the assessment of tremor; (2) used in published studies by people other than the developers; and (3) adequate clinimetric testing. Accelerometry, gyroscopy, electromyography, and digitizing tablet-based measures fulfilled all three criteria. Compared to rating scales, transducers are far more sensitive to changes in tremor amplitude and frequency, but they do not appear to be more capable of detecting a change that exceeds random variability in tremor amplitude (minimum detectable change). The use of transducer-based measures requires careful attention to their limitations and validity in a particular clinical or research setting. © 2016 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Dietrich Haubenberger
- Clinical Trials Unit, Office of the Clinical Director, National Institutes of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
| | | | - Peter G Bain
- Department of Neurology, Imperial College London, Charing Cross Hospital, London, United Kingdom
| | - Nin Bajaj
- Department of Neurology, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
| | - Julián Benito-León
- Department of Neurology, University Hospital "12 de Octubre", Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Department of Medicine, Complutense University, Madrid, Spain
| | - Kailash P Bhatia
- Sobell Department for Movement Neuroscience, UCL, Institute of Neurology, Queen Square, London, United Kingdom
| | - Günther Deuschl
- Department of Neurology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Maria João Forjaz
- National School of Public Health and Red de Investigación en Servicios Sanitarios y Enfermedades Crónicas (REDISSEC), Carlos III Institute of Health, Madrid, Spain
| | - Mark Hallett
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Elan D Louis
- Departments of Neurology and Chronic Disease Epidemiology, Yale School of Medicine and Yale School of Public Health, Yale University, New Haven, Connecticut, USA
| | - Kelly E Lyons
- University of Kansas Medical Center, Kansas City, Kansas
| | - Tiago A Mestre
- Parkinson's disease and Movement Disorders Center, Division of Neurology, Department of Medicine, University of Ottawa, The Ottawa Hospital Research Institute, Ottawa Brain and Mind Research Institute, Ottawa, Ontario, Canada
| | - Jan Raethjen
- Department of Neurology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Maria Stamelou
- Neurology Department, University of Athens, Greece and Neurology Department, Philipps University, Marburg, Germany
| | - Eng-King Tan
- Department of Neurology, National Neuroscience Institute (SGH campus), Duke NUS Medical School, Singapore General Hospital, Singapore
| | - Claudia M Testa
- Department of Neurology and Parkinson's and Movement Disorders Center, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
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Elble RJ, McNames J. Using Portable Transducers to Measure Tremor Severity. Tremor Other Hyperkinet Mov (N Y) 2016; 6:375. [PMID: 27257514 PMCID: PMC4872171 DOI: 10.7916/d8dr2vcc] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/23/2016] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Portable motion transducers, suitable for measuring tremor, are now available at a reasonable cost. The use of these transducers requires knowledge of their limitations and data analysis. The purpose of this review is to provide a practical overview and example software for using portable motion transducers in the quantification of tremor. METHODS Medline was searched via PubMed.gov in December 2015 using the Boolean expression "tremor AND (accelerometer OR accelerometry OR gyroscope OR inertial measurement unit OR digitizing tablet OR transducer)." Abstracts of 419 papers dating back to 1964 were reviewed for relevant portable transducers and methods of tremor analysis, and 105 papers written in English were reviewed in detail. RESULTS Accelerometers, gyroscopes, and digitizing tablets are used most commonly, but few are sold for the purpose of measuring tremor. Consequently, most software for tremor analysis is developed by the user. Wearable transducers are capable of recording tremor continuously, in the absence of a clinician. Tremor amplitude, frequency, and occurrence (percentage of time with tremor) can be computed. Tremor amplitude and occurrence correlate strongly with clinical ratings of tremor severity. DISCUSSION Transducers provide measurements of tremor amplitude that are objective, precise, and valid, but the precision and accuracy of transducers are mitigated by natural variability in tremor amplitude. This variability is so great that the minimum detectable change in amplitude, exceeding random variability, is comparable for scales and transducers. Research is needed to determine the feasibility of detecting smaller change using averaged data from continuous long-term recordings with wearable transducers.
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Affiliation(s)
- Rodger J. Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - James McNames
- Department of Electrical and Computer Engineering, Maseeh College of Engineering and Computer Science, Portland State University, Portland, OR, USA
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Elkouzi A, Kattah JC, Elble RJ. Hypertrophic Olivary Degeneration Does Not Reduce Essential Tremor. Mov Disord Clin Pract 2015; 3:209-211. [PMID: 30713917 DOI: 10.1002/mdc3.12275] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 08/11/2015] [Accepted: 08/17/2015] [Indexed: 12/20/2022] Open
Affiliation(s)
- Ahmad Elkouzi
- Southern Illinois University School of Medicine Springfield Illinois USA
| | - Jorge C Kattah
- University of Illinois College of Medicine at Peoria Peoria Illinois USA
| | - Rodger J Elble
- Southern Illinois University School of Medicine Springfield Illinois USA
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Bhargava P, Elble RJ. Clinical reasoning: an unusual cause of transverse myelitis? Author response. Neurology 2014; 83:666-667. [PMID: 25254265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
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Affiliation(s)
- Rodger J Elble
- Professor of Neurology, Southern Illinois University School of Medicine. E-mail:
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Elble RJ. Is essential tremor a dementing neurodegenerative disease? Neurobiol Aging 2014. [DOI: 10.1016/j.neurobiolaging.2014.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Affiliation(s)
- Pavan Bhargava
- From the Department of Neurology, Southern Illinois University School of Medicine, Springfield
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Kaul S, Elble RJ. Impaired pentagon drawing is an early predictor of cognitive decline in Parkinson's disease. Mov Disord 2014; 29:427-8. [PMID: 24449089 DOI: 10.1002/mds.25807] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Revised: 12/10/2013] [Accepted: 12/18/2013] [Indexed: 11/06/2022] Open
Affiliation(s)
- Siddharth Kaul
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois, USA
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Abstract
A strong association between dystonia and tremor has been known for more than a century. Two forms of tremor in dystonia are currently recognized: 1) dystonic tremor, which is tremor produced by dystonic muscle contraction and 2) tremor associated with dystonia, which is tremor in a body part that is not dystonic, but there is dystonia elsewhere. Both forms of tremor in dystonia frequently resemble essential tremor or another pure tremor syndrome (e.g., isolated head and voice tremors and task-specific writing tremor), and relationships among these tremor disorders have long been debated. Misdiagnosis is common because mild dystonia is frequently overlooked in patients with tremor. It is now clear that essential tremor is a syndrome, not a specific disease, and the use of essential tremor as a specific clinical diagnosis is arguably an impediment to elucidating this and other pure tremor syndromes and their relationship to dystonia. A new classification, primary tremor, is proposed and would be used for any disorder in which tremor is the sole or principal abnormality with no identifiable etiology other than possible genetic inheritance. This classification scheme would facilitate tremor research by moving the focus from the narrow question "Is it essential tremor?" to a broader consideration of what genetic and environmental factors cause primary tremor disorders, and how do they relate to dystonia and other neurological disorders.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, 751 North Rutledge, PO Box 19643, Springfield, IL 62794-9643, USA
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Carranza MA, Snyder MR, Elble RJ, Boutzoukas AE, Zesiewicz TA. Methodological issues in clinical drug development for essential tremor. Tremor Other Hyperkinet Mov (N Y) 2013; 2. [PMID: 23440401 PMCID: PMC3570037 DOI: 10.7916/d8p55m7f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 05/30/2012] [Indexed: 12/01/2022]
Abstract
Essential tremor (ET) is one of the most common tremor disorders in the world. Despite this, only two medications have received Level A recommendations from the American Academy of Neurology to treat it (primidone and propranolol). Even though these medications provide relief to a large group of ET patients, up to 50% of patients are non-responders. Additional medications to treat ET are needed. This review discusses some of the methodological issues that should be addressed for quality clinical drug development in ET.
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Affiliation(s)
- Michael A Carranza
- Department of Neurology, University of South Florida, Tampa, Florida, United States of America
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Zesiewicz TA, Elble RJ, Louis ED, Gronseth GS, Ondo WG, Dewey RB, Okun MS, Sullivan KL, Weiner WJ. Evidence-based guideline update: treatment of essential tremor: report of the Quality Standards subcommittee of the American Academy of Neurology. Neurology 2011; 77:1752-5. [PMID: 22013182 DOI: 10.1212/wnl.0b013e318236f0fd] [Citation(s) in RCA: 186] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND This evidence-based guideline is an update of the 2005 American Academy of Neurology practice parameter on the treatment of essential tremor (ET). METHODS A literature review using MEDLINE, EMBASE, Science Citation Index, and CINAHL was performed to identify clinical trials in patients with ET published between 2004 and April 2010. RESULTS AND RECOMMENDATIONS Conclusions and recommendations for the use of propranolol, primidone (Level A, established as effective); alprazolam, atenolol, gabapentin (monotherapy), sotalol, topiramate (Level B, probably effective); nadolol, nimodipine, clonazepam, botulinum toxin A, deep brain stimulation, thalamotomy (Level C, possibly effective); and gamma knife thalamotomy (Level U, insufficient evidence) are unchanged from the previous guideline. Changes to conclusions and recommendations from the previous guideline include the following: 1) levetiracetam and 3,4-diaminopyridine probably do not reduce limb tremor in ET and should not be considered (Level B); 2) flunarizine possibly has no effect in treating limb tremor in ET and may not be considered (Level C); and 3) there is insufficient evidence to support or refute the use of pregabalin, zonisamide, or clozapine as treatment for ET (Level U).
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Elble RJ, Suchowersky O, Shaftman S, Weiner WJ, Huang P, Tilley B. Impact of belief in neuroprotection on therapeutic intervention in Parkinson's disease. Mov Disord 2010; 25:1082-6. [DOI: 10.1002/mds.22997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Elble RJ, Biondi DM, Ascher S, Wiegand F, Hulihan J. Carisbamate in essential tremor: Brief report of a proof of concept study. Mov Disord 2010; 25:634-8. [DOI: 10.1002/mds.22872] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Louis ED, Faust PL, Vonsattel JPG, Honig LS, Rajput A, Rajput A, Pahwa R, Lyons KE, Ross WG, Elble RJ, Erickson-Davis C, Moskowitz CB, Lawton A. Torpedoes in Parkinson's disease, Alzheimer's disease, essential tremor, and control brains. Mov Disord 2009; 24:1600-5. [PMID: 19526585 PMCID: PMC2736313 DOI: 10.1002/mds.22567] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Purkinje cell axonal swellings ("torpedoes"), described in several cerebellar disorders as well as essential tremor (ET), have not been quantified in common neurodegenerative conditions. The aim of this study was to quantify torpedoes Parkinson's disease (PD) and Alzheimer's disease (AD) compared with ET and control brains. Brains included 40 ET cases (34 cerebellar ET, 6 Lewy body variant of ET) and age-matched comparison brains (21 AD, 14 PD/diffuse Lewy body disease, 25 controls). Torpedoes were counted in 20 x 25 mm cerebellar cortical sections stained with Luxol Fast Blue/Hematoxylin and Eosin. The median number of torpedoes in cerebellar ET (12) was 12x higher than that of controls (1) and nearly 2.5x higher than in AD (5) or PD/DLBD (5) (all P < or = 0.005). Furthermore, in a logistic regression model that adjusted for age and Alzheimer's-type changes, each torpedo more than doubled the odds of having cerebellar ET (Odds ratio(cerebellar ET vs. control) = 2.57, P = 0.006), indicating that the association between increased torpedoes and cerebellar ET was independent of these Alzheimer's-type changes. Although torpedoes are increased in AD and PD, as well as cerebellar ET, the magnitude of increase in cerebellar ET is greater, and cannot be accounted for by concomitant AD or PD pathology.
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Affiliation(s)
- Elan D Louis
- GH Sergievsky Center, Columbia University, New York, New York, USA.
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Stacy MA, Elble RJ, Ondo WG, Wu SC, Hulihan J. Assessment of interrater and intrarater reliability of the Fahn-Tolosa-Marin Tremor Rating Scale in essential tremor. Mov Disord 2007; 22:833-8. [PMID: 17343274 DOI: 10.1002/mds.21412] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The purpose of this study was to evaluate interrater and intrarater reliability of the Fahn-Tolosa-Marin Tremor Rating Scale (TRS) in essential tremor (ET). Proper treatment of ET is contingent upon correct assessment of the severity, loss of function, and disability related to tremor. Videotape recordings of 17 subjects with ET evaluated with the TRS were produced and sent to 59 raters. Once the raters returned the videotape and completed the score sheet, they were mailed a second tape with the same recordings presented in a different order. In the interrater reliability evaluation, modified Kappa statistics for seven tremor type composites ranged from 0.10 to 0.65 in the first videotape and 0.17 to 0.62 in the second videotape. Interrater reliabilities were greater for Part A items (magnitude of tremor in different body parts) than for Part B items (tremor in writing and drawings) of the TRS. The average Spearman correlation was 0.87, indicating very good consistency between the two videotapes, but correlations for Part A were somewhat better than for Part B. It is best when the same rater performs repeated measures of tremor on a patient, particularly when judging tremor in handwriting and drawings. Training of raters on use of the TRS would help standardize judgement.
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Affiliation(s)
- Mark A Stacy
- Division of Neurology, Duke University Medical Center, Durham, North Carolina 27705, USA.
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Abstract
Highest level gait disorders are produced by pathology in one or more structures in the cortical-basal ganglia-thalamocortical loop, which plays an important role in producing movements and postural synergies that meet personal desires and environmental constraints. Virtually all patients with dementia have pathology in one or more components of this loop, so highest level gait disorders are common in patients with dementia. The terminology surrounding these gait disorders is unnecessarily complex and too heavily influenced by the controversial concept of gait apraxia. Straightforward descriptive diagnostic criteria are needed. To this end, four core clinical features of highest level gait disorders are proposed: 1) inappropriate (counterproductive) or bizarre limb movement, postural synergies, and interaction with the environment, 2) qualitatively variable performance, influenced greatly by the environment and emotion, 3) hesitation and freezing, and 4) absent or inappropriate (counterproductive) rescue reactions. These core features follow logically from the physiology of the cortical-basal ganglia-thalamocortical loop and should be regarded as signs of pathology in this loop. A clinical rating scale based on these features should be developed to facilitate clinical diagnosis and clinicopathological correlation, while avoiding the ambiguities and controversies of gait apraxia.
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Affiliation(s)
- R J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL 62794-9643, USA.
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Elble RJ, Pullman SL, Matsumoto JY, Raethjen J, Deuschl G, Tintner R. Tremor amplitude is logarithmically related to 4- and 5-point tremor rating scales. Brain 2006; 129:2660-6. [PMID: 16891320 DOI: 10.1093/brain/awl190] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Tremor rating scales (TRSs) are used commonly in the clinical assessment of tremor, but the relationship of a TRS to actual tremor amplitude has never been quantified. Consequently, the resolution of these scales is unknown, and the clinical significance of a 1-point change in TRS is uncertain. We therefore sought to determine the change in tremor amplitude that corresponds to a 1-point change in a typical 5-point TRS. Data from five laboratories were analysed, and 928 patients with various types of hand tremor were studied. Hand tremor was quantified with a graphics tablet in three different labs, an accelerometer in three labs and a mechanical-linkage device in one lab. Tremor in writing, drawing, horizontal posture, rest and finger-nose testing was graded using a variety of TRSs. The relationship between TRS scores and tremor amplitude was computed for each task and laboratory. A logarithmic relationship between a 5-point (0-4) TRS and tremor amplitude (T, measured in centimetres) was found in all five labs, despite widely varying rating scales and transducer methodology. Thus, T2/T1 = 10(alpha(TRS2-TRS1)). The value of alpha ranged from 0.414 to 0.441 for writing, 0.355-0.574 for spiral drawing, 0.441 to 0.488 for rest tremor, 0.266-0.577 for postural tremor and 0.306 for finger-nose testing. For alpha = 0.3, 0.4, 0.5, 0.6 and 0.7, the ratios T2/T1 for a 1-point decrease in TRS are 0.501, 0.398, 0.316, 0.251 and 0.200. Therefore, a 1-point change in TRS represents a substantial change in tremor amplitude. Knowledge of the relationship between TRS and precise measures of tremor is useful in interpreting the clinical significance of changes in TRS produced by disease or therapy.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, IL 62795-9643, USA.
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Pyo G, Elble RJ, Ala T, Markwell SJ. The Characteristics of Patients With Uncertain/Mild Cognitive Impairment on the Alzheimer Disease Assessment Scale-Cognitive Subscale. Alzheimer Dis Assoc Disord 2006; 20:16-22. [PMID: 16493231 DOI: 10.1097/01.wad.0000201846.22213.76] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The performances of the uncertain/mild cognitive impairment (MCI) patients on the Alzheimer Disease Assessment Scale-Cognitive (ADAS-Cog) subscale were compared with those of normal controls, Alzheimer disease patients with CDR 0.5, and Alzheimer disease patients with CDR 1.0. The Uncertain/MCI group was significantly different from normal controls and Alzheimer disease CDR 0.5 or 1.0 groups on the ADAS-Cog except on a few non-memory subtests. Age was significantly correlated with total error score in the normal group, but there was no significant correlation between age and ADAS-Cog scores in the patient groups. Education was not significantly correlated with the ADAS-Cog scores in any group. Regardless of age and educational level, there were clear differences between the normal group and the Uncertain/MCI group, especially on the total error scores. We found that the total error score of the ADAS-Cog was the most reliable variable in detecting patients with mild cognitive impairment. The present study demonstrated that the ADAS-Cog is a promising tool for detecting and studying patients with mild cognitive impairment. The results also indicated that demographic variables such as age and education do not play a significant role in the diagnosis of mild cognitive impaired patients based on the ADAS-Cog scores.
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Affiliation(s)
- Geunyeong Pyo
- Department of Psychiatry, Southern Illinois University School of Medicine, Springfield, IL 62794-9642, USA.
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Abstract
Seventy researchers met in Washington, DC, on 20-21 October 2005 to identify and discuss the most pressing research issues in essential tremor (ET). The conference attendees concluded that the following six objectives are of immediate and overriding importance: (1) a collaborative network of research centers; (2) an international committee for developing a standard protocol for the diagnosis and quantification of ET; (3) the identification of one or more genes for ET; (4) a centralized repository of DNA and, ideally, immortalized cell lines from well-characterized ET families and healthy controls; (5) a reliable and efficient repository of optimally prepared and categorized brain samples for hypothesis-driven neuropathological examinations in well-characterized ET patients; and (6) animal models of ET for screening promising drugs. The conference attendees hope that this statement from the United States will engender international collaboration in finding a cure for ET.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois 62794, USA.
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Abstract
OBJECTIVE To illustrate the problem of gravitational artifact in accelerometric recordings of tremor. METHODS Gravitational and inertial accelerations were computed for a triaxial accelerometer that was attached to a hand, oscillating vertically about the wrist. Mathematical equations for hand motion were solved with commercial software. RESULTS Accelerometer output contains proportionately larger gravitational artifact at lower frequencies of oscillation and when the accelerometer is mounted closer to the wrist. A vertical accelerometer axis contains nearly constant gravitational artifact when the amplitude of wrist oscillation is less than +/-20 degrees. Proportionately large gravitational artifact can occur in accelerometer axes that are perpendicular to the path of motion. Gravitational and inertial oscillations at twice the frequency of wrist oscillation emerge from the equations of motion. CONCLUSIONS When the hand is horizontal, the vertical accelerometer axis contains nearly constant gravitational artifact during the recording of most tremors, and high-pass filtering effectively removes this artifact. Gravitational artifact is more problematic when the hand is vertical, as during the measurement of Parkinson rest tremor, particularly if the accelerometer is mounted close to the wrist. SIGNIFICANCE Two accelerometers, mounted in parallel, are needed to capture hand rotation in a single plane of motion, free of gravitational artifact.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, P.O. Box 19643, Springfield, IL 62794-9643, USA.
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Abstract
We electrophysiologically examined the transition from physiologic tremor to essential tremor in people at risk for familial essential tremor. Two healthy people from different families with hereditary essential tremor were studied on multiple occasions. A 23-year-old man was studied in 1995, 1997, and 2004, and a 44-year-old woman was studied in 1993, 1995, 1997, and 2003. Hand acceleration and forearm electromyographic readings were measured with and without 300-g loading to determine the characteristic frequency-invariant motor unit entrainment of essential tremor. Clinically and electrophysiologically, the man and woman had normal tremor until the last examination, when both exhibited a fine tremulousness in the outstretched hands and frequency-invariant motor unit entrainment at 7.5 and 6.5 Hz, respectively. At no time did either patient exhibit a prominent 8-12 Hz component of physiologic tremor. Essential tremor in young adults may begin at frequencies less than 8-12 Hz, and this electrophysiologic abnormality is detectable when clinical examinations reveal only questionably abnormal tremor. More young adults at risk for essential tremor must be studied to determine whether initial frequencies less than 8 Hz are the rule or the exception. Nevertheless, the data from our 2 patients demonstrate that a prominent 8-12 Hz component of physiologic tremor does not always precede the development of essential tremor; therefore, the origins of essential tremor and the 8-12 Hz component of physiologic tremor may be different.
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois 92794-9643, USA.
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Ala T, Hughes LF, Kyrouac GA, Ghobrial MW, Elble RJ. Use of MMSE to differentiate Alzheimer's disease from dementia with Lewy bodies--response to Larner. Int J Geriatr Psychiatry 2004; 19:1209; author reply 1209-10. [PMID: 15578752 DOI: 10.1002/gps.1192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Lyons KE, Pahwa R, Comella CL, Eisa MS, Elble RJ, Fahn S, Jankovic J, Juncos JL, Koller WC, Ondo WG, Sethi KD, Stern MB, Tanner CM, Tintner R, Watts RL. Benefits and risks of pharmacological treatments for essential tremor. Drug Saf 2003; 26:461-81. [PMID: 12735785 DOI: 10.2165/00002018-200326070-00003] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Essential tremor can cause significant functional disability in some patients. The arms are the most common body part affected and cause the most functional disability. The treatment of essential tremor includes medications, surgical options and other forms of therapy. Presently there is no cure for essential tremor nor are there any medications that can slow the progression of tremor. Treatment for essential tremor is recommended if the tremor causes functional disability. If the tremor is disabling only during periods of stress and anxiety, propranolol and benzodiazepines can be used during those periods when the tremor causes functional disability. The currently available medications can improve tremor in approximately 50% of the patients. If the tremor is disabling, treatment should be initiated with either primidone or propranolol. If either primidone or propranolol do not provide adequate control of the tremor, then the medications can be used in combination. If patients experience adverse effects with propranolol, occasionally other beta-adrenoceptor antagonists (such as atenolol or metoprolol) can be used. If primidone and propranolol do not provide adequate control of tremor, occasionally the use of benzodiazepines (such as clonazepam) can provide benefit. Other medications that may be helpful include gabapentin or topiramate. If a patient has disabling head or voice tremor, botulinum toxin injections into the muscles may provide relief from the tremor. Botulinum toxin in the hand muscles for hand tremor can result in bothersome hand weakness and is not widely used. There are other medications that have been tried in essential tremor and have questionable efficacy. These drugs include carbonic anhydrase inhibitors (e.g. methazolamide), phenobarbital, calcium channel antagonists (e.g. nimodipine), isoniazid, clonidine, clozapine and mirtazapine. If the patient still has disabling tremor after medication trials, surgical options are usually considered. Surgical options include thalamotomy and deep brain stimulation of the thalamus. These surgical options provide adequate tremor control in approximately 90% of the patients. Surgical morbidity and mortality for these procedures is low. Deep brain stimulation and thalamotomy have been shown to have comparable efficacy but fewer complications have been reported with deep brain stimulation. In patients undergoing bilateral procedures deep brain stimulation of the thalamus is the procedure of choice to avoid adverse effects seen with bilateral ablative procedures. The use of medication and/or surgery can provide adequate tremor control in the majority of the patients.
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Affiliation(s)
- Kelly E Lyons
- University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Affiliation(s)
- Rodger J Elble
- Department of Neurology, Southern Illinois University School of Medicine, Springfield, Illinois 62794-9643, USA.
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Ala TA, Hughes LF, Kyrouac GA, Ghobrial MW, Elble RJ. The Mini-Mental State exam may help in the differentiation of dementia with Lewy bodies and Alzheimer's disease. Int J Geriatr Psychiatry 2002; 17:503-9. [PMID: 12112173 DOI: 10.1002/gps.550] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE Since patients with dementia with Lewy bodies (DLB) tend to have greater impairment of attention and construction and better memory ability on neuropsychological tests than patients with Alzheimer's disease (AD), we determined if the items that measure attention, memory, and construction in the Mini-Mental State Examination (MMSE) help to distinguish DLB from AD early in the course of the dementia. DESIGN We retrospectively studied the first available MMSE exam for each of our patients with DLB or AD and compared their MMSE subscores for attention, memory, and construction. SETTING A university dementia brain bank in central Illinois, USA. PATIENTS All patients with neuropathologically-proven DLB or AD with MMSE scores > or =13. RESULTS We identified 17 DLB and 27 AD patients for whom we had MMSE exams. The attention and construction subtest scores of the DLB group were worse (p=0.0071 and p=0.0038, respectively) than those of the AD group. The memory subscores of the DLB group were better, although the difference did not reach statistical significance (p=0.22). When a mathematical equation was used to combine the three subscores with equal weighting (Attention-5/3Memory+5.Construction), the scores of the DLB group were worse (p=0.00007). Using this equation, a score less than 5 points was associated with DLB with a sensitivity of 0.82 (95% Confidence Interval (CI)=0.57-0.96) and a specificity of 0.81 (95% CI=0.62-0.94). CONCLUSIONS Our findings support the work of others regarding the relative neuropsychological impairments of DLB and AD and indicate that the MMSE may be helpful in the differentiation of DLB and AD.
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Affiliation(s)
- Thomas A Ala
- Center for Alzheimer Disease and Related Disorders, Department of Neurology, Southern Illinois University School of Medicine, PO Box 19643, Springfield, IL 62794-9643, USA.
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