1
|
Angelini L, Paparella G, Cannavacciuolo A, Costa D, Birreci D, De Riggi M, Passaretti M, Colella D, Guerra A, Berardelli A, Bologna M. Clinical and kinematic characterization of parkinsonian soft signs in essential tremor. J Neural Transm (Vienna) 2024:10.1007/s00702-024-02784-0. [PMID: 38744708 DOI: 10.1007/s00702-024-02784-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/06/2024] [Indexed: 05/16/2024]
Abstract
BACKGROUND Subtle parkinsonian signs, i.e., rest tremor and bradykinesia, are considered soft signs for defining essential tremor (ET) plus. OBJECTIVES Our study aimed to further characterize subtle parkinsonian signs in a relatively large sample of ET patients from a clinical and neurophysiological perspective. METHODS We employed clinical scales and kinematic techniques to assess a sample of 82 ET patients. Eighty healthy controls matched for gender and age were also included. The primary focus of our study was to conduct a comparative analysis of ET patients (without any soft signs) and ET-plus patients with rest tremor and/or bradykinesia. Additionally, we investigated the asymmetry and side concordance of these soft signs. RESULTS In ET-plus patients with parkinsonian soft signs (56.10% of the sample), rest tremor was clinically observed in 41.30% of cases, bradykinesia in 30.43%, and rest tremor plus bradykinesia in 28.26%. Patients with rest tremor had more severe and widespread action tremor than other patients. Furthermore, we observed a positive correlation between the amplitude of action and rest tremor. Most ET-plus patients had an asymmetry of rest tremor and bradykinesia. There was no side concordance between these soft signs, as confirmed through both clinical examination and kinematic evaluation. CONCLUSIONS Rest tremor and bradykinesia are frequently observed in ET and are often asymmetric but not concordant. Our findings provide a better insight into the phenomenology of ET and suggest that the parkinsonian soft signs (rest tremor and bradykinesia) in ET-plus may originate from distinct pathophysiological mechanisms.
Collapse
Affiliation(s)
- Luca Angelini
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
| | - Giulia Paparella
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | | | - Davide Costa
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
| | - Daniele Birreci
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Martina De Riggi
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Massimiliano Passaretti
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Donato Colella
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Andrea Guerra
- Parkinson and Movement Disorders Unit, Study Center on Neurodegeneration (CESNE), Department of Neuroscience, University of Padua, Padua, Italy
- Padova Neuroscience Center (PNC), University of Padua, Padua, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy
| | - Matteo Bologna
- IRCCS Neuromed, Via Atinense, 18, Pozzilli (IS), 86077, Italy.
- Department of Human Neurosciences, Sapienza University of Rome, Viale dell'Università, 30, Rome, 00185, Italy.
| |
Collapse
|
2
|
Iglesias-Hernandez D, Delgado N, McGurn M, Huey ED, Cosentino S, Louis ED. "ET Plus": Instability of the Diagnosis During Prospective Longitudinal Follow-up of Essential Tremor Cases. Front Neurol 2021; 12:782694. [PMID: 34975736 PMCID: PMC8716461 DOI: 10.3389/fneur.2021.782694] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/26/2021] [Indexed: 11/13/2022] Open
Abstract
Background: A recent consensus statement introduced the term "ET plus". Although investigators have quantified the prevalence of ET plus in cross-sectional studies, patients with ET plus have not been tracked longitudinally; hence, there is no understanding of its stability over time. Methods: We present prospective, longitudinal phenotypic data on an ET cohort that was followed regularly at 18-month intervals (T1, T2, T3, T4) for up to 64 months. We assigned an ET or ET plus diagnosis to each case at each time interval. Results: There were 201 participants at baseline. The proportion with ET plus increased from 58.7% at baseline to 72.1% at T4 (p = 0.046). Of 172 (85.6%) who received a diagnosis of ET plus at one or more time intervals, the diagnosis was unstable (e.g., with reversion) in 62 (36.0%). We also assessed the stability of the clinical features of ET plus. Rest tremor was the most unstable clinical feature of ET plus; it was present in 59 participants, among whom it reverted from present to absent in 23 (39.0%). By contrast, for "memory impairment" (i.e., either mild cognitive impairment or dementia), the proportion who reverted from present to absent was only 21.3%. Conclusion: These data support our two a priori hypotheses: (1) the prevalence of ET plus would increase progressively, as it likely represents a more advanced stage of ET, and (2) the ET plus diagnosis would not be stable over time, as cases would fluctuate with respect to their phenotypic features and their assigned diagnoses.
Collapse
Affiliation(s)
| | - Nikki Delgado
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Margaret McGurn
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Edward D. Huey
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, United States
- 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 Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Stephanie Cosentino
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, United States
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Elan D. Louis
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| |
Collapse
|
3
|
Abstract
Tremor is the most commonly encountered movement disorder in clinical practice. A wide range of pathologies may manifest with tremor either as a presenting or predominant symptom. Considering the marked etiological and phenomenological heterogeneity, it would be desirable to develop a classification of tremors that reflects their underlying pathophysiology. The tremor task force of the International Parkinson Disease and Movement Disorders Society has worked toward this goal and proposed a new classification system. This system has remained a prime topic of scientific communications on tremor in recent times. The new classification is based on two axes: 1. based on the clinical features, history, and tremor characteristics and 2. based on the etiology of tremor. In this article, we discuss the key aspects of the new classification, review various tremor syndromes, highlight some of the controversies in the field of tremor, and share the potential future perspectives.
Collapse
Affiliation(s)
- Abhishek Lenka
- Department of Neurology, Medstar Georgetown University Hospital, Washington, DC, United States
| | - Joseph Jankovic
- Parkinson's Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX, United States
| |
Collapse
|
4
|
Shahtalebi S, Atashzar SF, Patel RV, Jog MS, Mohammadi A. A deep explainable artificial intelligent framework for neurological disorders discrimination. Sci Rep 2021; 11:9630. [PMID: 33953261 PMCID: PMC8099874 DOI: 10.1038/s41598-021-88919-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 04/13/2021] [Indexed: 02/03/2023] Open
Abstract
Pathological hand tremor (PHT) is a common symptom of Parkinson's disease (PD) and essential tremor (ET), which affects manual targeting, motor coordination, and movement kinetics. Effective treatment and management of the symptoms relies on the correct and in-time diagnosis of the affected individuals, where the characteristics of PHT serve as an imperative metric for this purpose. Due to the overlapping features of the corresponding symptoms, however, a high level of expertise and specialized diagnostic methodologies are required to correctly distinguish PD from ET. In this work, we propose the data-driven [Formula: see text] model, which processes the kinematics of the hand in the affected individuals and classifies the patients into PD or ET. [Formula: see text] is trained over 90 hours of hand motion signals consisting of 250 tremor assessments from 81 patients, recorded at the London Movement Disorders Centre, ON, Canada. The [Formula: see text] outperforms its state-of-the-art counterparts achieving exceptional differential diagnosis accuracy of [Formula: see text]. In addition, using the explainability and interpretability measures for machine learning models, clinically viable and statistically significant insights on how the data-driven model discriminates between the two groups of patients are achieved.
Collapse
Affiliation(s)
- Soroosh Shahtalebi
- grid.410319.e0000 0004 1936 8630Concordia Institute for Information Systems Engineering, Concordia University, Montreal, QC H3G 1M8 Canada
| | - S. Farokh Atashzar
- grid.137628.90000 0004 1936 8753Departments of Electrical and Computer Engineering, and Mechanical and Aerospace Engineering, New York University (NYU), New York, NY 10003 USA ,grid.137628.90000 0004 1936 8753NYU WIRELESS and NYU Center for Urban Science and Progress (CUSP), New York University (NYU), New York, NY 10003 USA
| | - Rajni V. Patel
- grid.39381.300000 0004 1936 8884Department of Electrical and Computer Engineering, Western University, London, ON N6A 5B9 Canada ,grid.39381.300000 0004 1936 8884Department of Clinical Neurological Sciences, Western University, London, ON N6A 3K7 Canada
| | - Mandar S. Jog
- grid.39381.300000 0004 1936 8884Department of Electrical and Computer Engineering, Western University, London, ON N6A 5B9 Canada ,grid.39381.300000 0004 1936 8884Department of Clinical Neurological Sciences, Western University, London, ON N6A 3K7 Canada
| | - Arash Mohammadi
- grid.410319.e0000 0004 1936 8630Concordia Institute for Information Systems Engineering, Concordia University, Montreal, QC H3G 1M8 Canada
| |
Collapse
|
5
|
Jombík P, Spodniak P, Bahýľ V, Necpál J. Visualisation of Parkinsonian, essential and physiological tremor planes in 3Dspace. Physiol Res 2021; 69:331-337. [PMID: 32199005 DOI: 10.33549/physiolres.934066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Based on the fact that tremors display some distinct 3D spatial characteristics, we decided to visualise tremor planes in 3D space. We obtained 3-axial linear accelerometer signals of hand tremors from 58 patients with Parkinson´s disease (PD), 37 with isolated resting tremor (iRT), 75 with essential tremor (ET), and 44 healthy volunteers with physiological tremor (Ph). For each group analysis was done with subsequent spatial 3D regression of the input data i.e. along the x, y and z axes; the projected vector lengths in the individual (vertical transversal XY, vertical longitudinal XZ and horizontal YZ) reference frame planes and their angles. Most meaningful and statistically significant differences were found in the analyses of the 3D vector lengths. The tremor of the PD and the iRT group was oriented mainly in the horizontal YZ plane. The tremors of the patients with ET and Ph were oriented approximately in the midway between the all three referential planes with less tilt toward the vertical longitudinal XZ plane.
Collapse
Affiliation(s)
- P Jombík
- Department of Neurology, Laboratory of Clinical Neurophysiology, Zvolen Hospital, Zvolen, Slovak Republic.
| | | | | | | |
Collapse
|
6
|
Abstract
It is a clinical experience that acute lesions of the cerebellum induce pathological tremor, which tends to improve. However, quantitative characteristics, imaging correlates, and recovery of cerebellar tremor have not been systematically investigated. We studied the prevalence, quantitative parameters measured with biaxial accelerometry, and recovery of pathological tremor in 68 patients with lesions affecting the cerebellum. We also investigated the correlation between the occurrence and characteristics of tremor and lesion localization using 3D T1-weighted MRI images which were normalized and segmented according to a spatially unbiased atlas template for the cerebellum. Visual assessment detected pathological tremor in 19% while accelerometry in 47% of the patients. Tremor was present both in postural and intentional positions, but never at rest. Two types of pathological tremor were distinguished: (1) low-frequency tremor in 36.76% of patients (center frequency 2.66 ± 1.17 Hz) and (2) normal frequency-high-intensity tremor in 10.29% (center frequency 8.79 ± 1.43 Hz). The size of the lesion did not correlate with the presence or severity of tremor. Involvement of the anterior lobe and lobule VI was related to high tremor intensity. In all followed up patients with acute cerebellar ischemia, the tremor completely recovered within 8 weeks. Our results indicate that cerebellar lesions might induce pathological postural and intentional tremor of 2-3 Hz frequency. Due to its low frequency and low amplitude, quantitative tremorometry is neccessary to properly identify it. There is no tight correlation between lesion localization and quantitative characteristics of cerebellar tremor.
Collapse
|
7
|
Neurobehavioral performance of patients diagnosed with manganism and idiopathic Parkinson disease. Int Arch Occup Environ Health 2019; 92:383-394. [DOI: 10.1007/s00420-019-01415-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 02/05/2019] [Indexed: 10/27/2022]
|
8
|
Herrnstadt G, McKeown MJ, Menon C. Controlling a motorized orthosis to follow elbow volitional movement: tests with individuals with pathological tremor. J Neuroeng Rehabil 2019; 16:23. [PMID: 30709409 PMCID: PMC6359763 DOI: 10.1186/s12984-019-0484-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 01/15/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is a need for alternative treatment options for tremor patients who do not respond well to medications or surgery, either due to side effects or poor efficacy, or that are excluded from surgery. The study aims to evaluate feasibility of a voluntary-driven, speed-controlled tremor rejection approach with individuals with pathological tremor. The suppression approach was investigated using a robotic orthosis for suppression of elbow tremor. Importantly, the study emphasizes the performance in relation to the voluntary motion. METHODS Nine participants with either Essential Tremor (ET) or Parkinson's disease (PD) were recruited and tested off medication. The participants performed computerized pursuit tracking tasks following a sinusoid and a random target, both with and without the suppressive orthosis. The impact of the Tremor Suppression Orthosis (TSO) at the tremor and voluntary frequencies was determined by the relative power change calculated from the Power Spectral Density (PSD). Voluntary motion was, in addition, assessed by position and velocity tracking errors. RESULTS The suppressive orthosis resulted in a 94.4% mean power reduction of the tremor (p < 0.001) - a substantial improvement over reports in the literature. As for the impact to the voluntary motion, paired difference tests revealed no statistical effect of the TSO on the relative power change (p = 0.346) and velocity tracking error (p = 0.283). A marginal effect was observed for the position tracking error (p = 0.05). The interaction torque with the robotic orthosis was small (0.62 Nm) when compared to the maximum voluntary torque that can be exerted by adult individuals at the elbow joint. CONCLUSIONS Two key contributions of this work are first, a recently proposed approach is evaluated with individuals with tremor demonstrating high levels of tremor suppression; second, the impact of the approach to the voluntary motion is analyzed comprehensively, showing limited inhibition. This study also seeks to address a gap in studies with individuals with tremor where the impact of engineering solutions on voluntary motion is unreported. This study demonstrates feasibility of the wearable technology as an effective treatment that removes tremor with limited impediment to intentional motion. The goal for such wearable technology is to help individuals with pathological tremor regain independence in activities affected by the tremor condition. Further investigations are needed to validate the technology.
Collapse
Affiliation(s)
- Gil Herrnstadt
- Menrva Research Group, Schools of Mechatronic Systems Engineering and Engineering Science, Simon Fraser University, Burnaby, Canada
| | - Martin J McKeown
- Department of Medicine (Neurology) and Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, Canada
| | - Carlo Menon
- Menrva Research Group, Schools of Mechatronic Systems Engineering and Engineering Science, Simon Fraser University, Burnaby, Canada.
| |
Collapse
|
9
|
Bove F, Di Lazzaro G, Mulas D, Cocciolillo F, Di Giuda D, Bentivoglio AR. A role for accelerometry in the differential diagnosis of tremor syndromes. FUNCTIONAL NEUROLOGY 2019; 33:45-49. [PMID: 29633696 DOI: 10.11138/fneur/2018.33.1.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Accelerometry is a reliable tool for gauging the occurrence, amplitude and frequency of tremor. However, there is no consensus on criteria for accelerometric diagnosis of tremor syndromes. We enrolled 20 patients with essential tremor (ET), 20 with dystonic tremor (DT), and 20 with classic parkinsonian tremor (PD-T), all meeting accepted clinical criteria. All the patients underwent dopamine transporter imaging (by means of single-photon emission computed tomography) and triaxial accelerometric tremor analysis. The latter revealed groupwise differences in tremor frequency, peak dispersion, spectral coherence, unilaterality and resting vs action tremor amplitude. From the above, five diagnostic criteria were extrapolated for each condition. Receiver operating characteristic curves, depicting criteriabased scoring of each tremor type, showed negligible declines in specificity for scores ≥4 in patients with ET or DT and scores ≥3 in patients with PD-T, thus providing a simple scoring method (accelerometrically derived) for differential diagnosis of the principal tremor syndromes.
Collapse
|
10
|
Zhang B, Huang F, Liu J, Zhang D. A Novel Posture for Better Differentiation Between Parkinson's Tremor and Essential Tremor. Front Neurosci 2018; 12:317. [PMID: 29867328 PMCID: PMC5966572 DOI: 10.3389/fnins.2018.00317] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 04/24/2018] [Indexed: 11/13/2022] Open
Abstract
Due to a lack of reliable non-invasive bio-markers, misdiagnosis between Parkinson's disease and essential tremor is common. Although some assistive engineering approaches have been proposed, little acceptance has been obtained for these methods lack well-studied mechanisms and involve operator-dependent procedures. Aiming at a better differentiation between the two tremor causes, we present a novel posture, termed arm-rested posture, to ameliorate the quality of recorded tremor sequences. To investigate its efficacy, the posture was compared with another common posture, called arm-stretching posture, in fundamental aspects of tremor intensity and dominant frequency. A tremor-affected cohort comprising 50 subjects (PD = 26, ET = 24) with inhomogeneous tremor manifestation were recruited. From each subject, acceleration data of 5 min in terms of each posture were recorded. In the overall process, no operator-dependent procedures, such as data screening, was employed. The differentiation performance of the two postures were assessed by the index of discrimination coefficient and a receiver operating characteristic analysis based on binary logistic regression. The results of the differentiation assessment consistently demonstrate a better performance with the arm-rested posture than with the arm-stretching posture. As a by-product, factors of disease stage (incipient, progressed stage), spectrum estimate (PSD, bispectrum) and recording length (5-300s) were investigated. The significant effect of disease stage was only found in PD in terms of tremor intensity [F(1, 516) = 7.781, P < 0.05]. The bispectrum estimate was found to have better performance than the PSD estimate in extracting dominant frequency in terms of the discrimination coefficient. By extending the recording length, we noticed an increase in the performance of dominant frequency. The best result of the arm-rested posture was obtained with the maximum recording length of 300 s (area under the curve: 0.944, sensitivity: 92%, 1-specificity: 0%, accuracy: 96%), which is better than that of the arm-stretching posture in the same condition (area under the curve: 0.734, sensitivity: 54%, 1-specificity: 12%, accuracy: 72%). Thus, we conclude that the arm-rested posture can assist in improving tremor differentiation between Parkinson's disease and essential tremor and may act as a universal tool to analyze tremor for both clinical and research purpose.
Collapse
Affiliation(s)
- Bin Zhang
- State Key Laboratory of Mechanical Systems and Vibrations, Robotics Institute, Shanghai Jiao Tong University, Shanghai, China
| | - Feifei Huang
- Department of Neurology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jun Liu
- Department of Neurology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Dingguo Zhang
- State Key Laboratory of Mechanical Systems and Vibrations, Robotics Institute, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
11
|
Kwon KY, Ryu HS, Lee HM, Kim MJ, Shin HW, Park HK, You S, Sung YH, Chung SJ, Koh SB. Hand Tremor Questionnaire: A Useful Screening Tool for Differentiating Patients with Hand Tremor between Parkinson's Disease and Essential Tremor. J Clin Neurol 2018; 14:381-386. [PMID: 29971978 PMCID: PMC6031988 DOI: 10.3988/jcn.2018.14.3.381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/20/2018] [Accepted: 03/23/2018] [Indexed: 11/17/2022] Open
Abstract
Background and Purpose Hand tremor is one of the most frequent symptoms in movement disorders, and differential diagnoses for hand tremor include Parkinson's disease (PD) and essential tremor (ET). However, accurately differentiating between PD and ET in clinical practice remains challenging in patients presenting with hand tremor. We investigated whether a questionnaire-based survey could be useful as a screening tool in patients with hand tremor. Methods A questionnaire related to hand tremor consisting of 12 items was prospectively applied to patients with PD or ET in three movement-disorder clinics. Each question was analyzed, and a query-based scoring system was evaluated for differentiating hand tremors between PD and ET. Results This study enrolled 24 patients with PD and 25 patients with ET. Nine of the 12 questions differed significantly between PD and ET: 1 about resting tremor, 4 questions about action tremor, and 4 about asymmetry. A receiver operating characteristics curve analysis revealed that the 9-item questionnaire showed a good discrimination ability, with a sensitivity of 88% and a specificity of 84%. Conclusions The developed Hand Tremor Questionnaire might be a good screening tool for hand tremors in patients with PD and ET.
Collapse
Affiliation(s)
- Kyum Yil Kwon
- Department of Neurology, Soonchunhyang University Seoul Hospital, Soonchunhyang University School of Medicine, Seoul, Korea
| | - Ho Sung Ryu
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Hye Mi Lee
- Department of Neurology and Parkinson's Disease Centre, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Mi Jung Kim
- Department of Neurology and Parkinson's Disease Centre, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Hae Won Shin
- Department of Neurology, Chung-Ang University College of Medicine, Seoul, Korea
| | - Hee Kyung Park
- Department of Neurology, Inje University College of Medicine, Ilsan Paik Hospital, Goyang, Korea
| | - Sooyeoun You
- Department of Neurology, Dongsan Medical Center, Keimyung University, Daegu, Korea
| | - Young Hee Sung
- Department of Neurology, College of Medicine, Gachon University, Incheon, Korea
| | - Sun Ju Chung
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
| | - Seong Beom Koh
- Department of Neurology and Parkinson's Disease Centre, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
| |
Collapse
|
12
|
González Rojas HA, Cuevas PC, Zayas Figueras EE, Foix SC, Sánchez Egea AJ. Time measurement characterization of stand-to-sit and sit-to-stand transitions by using a smartphone. Med Biol Eng Comput 2017; 56:879-888. [PMID: 29063366 DOI: 10.1007/s11517-017-1728-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 10/04/2017] [Indexed: 11/26/2022]
Abstract
The aim of this study is to analyze a common method to measure the acceleration of a daily activity pattern by using a smartphone. In this sense, a numerical approach is proposed to transform the relative acceleration signal, recorded by a triaxial accelerometer, into an acceleration referred to an inertial reference. The integration of this acceleration allows to determine the velocity and position with respect to an inertial reference. Two different kinematic parameters are suggested to characterize the profile of the velocity during the sit-to-stand and stand-to-sit transitions for Parkinson and control subjects. The results show that a dimensionless kinematic parameter, which is linked to the time of sit-to-stand and stand-to-sit transitions, has the potential to differentiate between Parkinson and control subjects.
Collapse
Affiliation(s)
- Hernán A González Rojas
- Department of Mechanical Engineering (EPSEVG), Universitat Politécnica de Catalunya, Av. de Víctor Balaguer 1, Vilanova i la Geltrú, 08800, Barcelona, Spain.
| | - Pedro Chaná Cuevas
- Centro de Trastornos del Movimiento (CETRAM), Facultad de Ciencias Médicas, Universidad de Santiago de Chile, Belisario Prats, 1597 B, Independencia, Santiago, Chile
| | - Enrique E Zayas Figueras
- Department of Mechanical Engineering (ETSEIB), Universitat Politécnica de Catalunya, Av. Diagonal, 647, 08028, Barcelona, Spain
| | - Salvador Cardona Foix
- Department of Mechanical Engineering (ETSEIB), Universitat Politécnica de Catalunya, Av. Diagonal, 647, 08028, Barcelona, Spain
| | - Antonio J Sánchez Egea
- Department of Mechanical Engineering (EPSEVG), Universitat Politécnica de Catalunya, Av. de Víctor Balaguer 1, Vilanova i la Geltrú, 08800, Barcelona, Spain
| |
Collapse
|
13
|
Lee HJ, Lee WW, Kim SK, Park H, Jeon HS, Kim HB, Jeon BS, Park KS. Tremor frequency characteristics in Parkinson's disease under resting-state and stress-state conditions. J Neurol Sci 2016; 362:272-7. [PMID: 26944162 DOI: 10.1016/j.jns.2016.01.058] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Revised: 12/08/2015] [Accepted: 01/26/2016] [Indexed: 10/22/2022]
Abstract
Tremor characteristics-amplitude and frequency components-are primary quantitative clinical factors for diagnosis and monitoring of tremors. Few studies have investigated how different patient's conditions affect tremor frequency characteristics in Parkinson's disease (PD). Here, we analyzed tremor characteristics under resting-state and stress-state conditions. Tremor was recorded using an accelerometer on the finger, under resting-state and stress-state (calculation task) conditions, during rest tremor and postural tremor. The changes of peak power, peak frequency, mean frequency, and distribution of power spectral density (PSD) of tremor were evaluated across conditions. Patients whose tremors were considered more than "mild" were selected, for both rest (n=67) and postural (n=25) tremor. Stress resulted in both greater peak powers and higher peak frequencies for rest tremor (p<0.001), but not for postural tremor. Notably, peak frequencies were concentrated around 5 Hz under stress-state condition. The distributions of PSD of tremor were symmetrical, regardless of conditions. Tremor is more evident and typical tremor characteristics, namely a lower frequency as amplitude increases, are different in stressful condition. Patient's conditions directly affect neural oscillations related to tremor frequencies. Therefore, tremor characteristics in PD should be systematically standardized across patient's conditions such as attention and stress levels.
Collapse
Affiliation(s)
- Hong Ji Lee
- The Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, Republic of Korea.
| | - Woong Woo Lee
- The Department of Neurology, Eulji General Hospital, Seoul, Republic of Korea
| | - Sang Kyong Kim
- The Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, Republic of Korea
| | - Hyeyoung Park
- The Department of Neurology and Movement Disorder Center, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hyo Seon Jeon
- The Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, Republic of Korea
| | - Han Byul Kim
- The Interdisciplinary Program for Bioengineering, Seoul National University, Seoul, Republic of Korea
| | - Beom S Jeon
- The Department of Neurology and Movement Disorder Center, Seoul National University Hospital, Seoul, Republic of Korea
| | - Kwang Suk Park
- The Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul, Republic of Korea.
| |
Collapse
|
14
|
Robakis D, Louis ED. Another case of "shopping bag" tremor: a difficult to classify action tremor. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2014; 4:269. [PMID: 25506044 PMCID: PMC4259080 DOI: 10.7916/d8pv6hvj] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 09/13/2014] [Indexed: 12/01/2022]
Abstract
This letter was written in response to: Zesiewicz T, Vu T, Carranza MA, et al. Unusual wrist tremor: unilateral isometric tremor?
Tremor Other Hyperkinet Mov. 2014; 4: http://tremorjournal.org/article/view/194
Collapse
Affiliation(s)
- Daphne Robakis
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Elan D Louis
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA ; GH Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY, USA ; Department of Epidemiology, Mailman School of Public Health, Columbia University, 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
| |
Collapse
|
15
|
Wu Y, Ding J, Gao Y, Chen S, Li L, Li R. Mini Review: linkages between essential tremor and Parkinson's disease? Front Cell Neurosci 2013; 7:118. [PMID: 23914155 PMCID: PMC3728484 DOI: 10.3389/fncel.2013.00118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/07/2013] [Indexed: 11/17/2022] Open
Abstract
Essential tremor (ET) and Parkinson’s disease (PD) are two of the most common movement disorders. Tremors are the primary symptoms of ET and of some PD patients, the two are often mistaken for each other. Especially since there are no available differentiate tests for the tremor of ET or PD, the early diagnoses mainly based on clinical assessments of medical symptoms, family and medication history, and examination by physicians. There is increasing evidence suggesting an association between ET and PD, such as a similar tremor frequency, overlapping resting tremors (a typical PD tremor), postural tremors (mainly in ET patients) in both ET and PD patients, and many ET patients develop PD later in life. Although it is difficult to make a differential diagnosis of ET and tremor-dominant PD based on clinical assessment, recent developments of objective measurements, such as brain imaging, neuropathology, and genetic analysis, has opened a helpful window for distinguishing ET from PD. In this mini review, we included literatures of ET and PD studies and discussed various advanced methods for differential diagnosis between ET and PD such as neuroimaging, genetic markers, tremor intensity and frequency, and drug-responses.
Collapse
Affiliation(s)
- Yiwen Wu
- 1 Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine Shanghai, China
| | | | | | | | | | | |
Collapse
|
16
|
Norman KE, Héroux ME. Measures of fine motor skills in people with tremor disorders: appraisal and interpretation. Front Neurol 2013; 4:50. [PMID: 23717299 PMCID: PMC3650669 DOI: 10.3389/fneur.2013.00050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/24/2013] [Indexed: 12/04/2022] Open
Abstract
People with Parkinson's disease, essential tremor, or other movement disorders involving tremor have changes in fine motor skills that are among the hallmarks of these diseases. Numerous measurement tools have been created and other methods devised to measure such changes in fine motor skills. Measurement tools may focus on specific features - e.g., motor skills or dexterity, slowness in movement execution associated with parkinsonian bradykinesia, or magnitude of tremor. Less obviously, some tools may be better suited than others for specific goals such as detecting subtle dysfunction early in disease, revealing aspects of brain function affected by disease, or tracking changes expected from treatment or disease progression. The purpose of this review is to describe and appraise selected measurement tools of fine motor skills appropriate for people with tremor disorders. In this context, we consider the tools' content - i.e., what movement features they focus on. In addition, we consider how measurement tools of fine motor skills relate to measures of a person's disease state or a person's function. These considerations affect how one should select and interpret the results of these tools in laboratory and clinical contexts.
Collapse
Affiliation(s)
- Kathleen E. Norman
- School of Rehabilitation Therapy, Queen’s UniversityKingston, ON, Canada
- Centre for Neuroscience Studies, Queen’s UniversityKingston, ON, Canada
| | | |
Collapse
|
17
|
Finger tapping clinimetric score prediction in Parkinson's disease using low-cost accelerometers. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2013; 2013:717853. [PMID: 23690760 PMCID: PMC3652130 DOI: 10.1155/2013/717853] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 03/04/2013] [Accepted: 03/05/2013] [Indexed: 11/18/2022]
Abstract
The motor clinical hallmarks of Parkinson's disease (PD) are usually quantified
by physicians using validated clinimetric scales such as the Unified Parkinson's Disease Rating Scale (MDS-UPDRS). However, clinical ratings are prone to subjectivity and inter-rater variability. The PD medical community is therefore looking for a simple, inexpensive, and objective rating method. As a first step towards this goal, a triaxial accelerometer-based system was used in a sample of 36 PD patients and 10 age-matched controls as they performed the MDS-UPDRS finger tapping (FT) task. First, raw signals were epoched to isolate the successive single FT movements. Next, eighteen FT task movement features were extracted, depicting MDS-UPDRS features and accelerometer specific features. An ordinal logistic regression model and a greedy backward
algorithm were used to identify the most relevant features in the prediction of MDS-UPDRS FT scores, given by 3 specialists in movement disorders (SMDs). The Goodman-Kruskal Gamma index obtained (0.961), depicting the predictive performance of the model, is similar to those obtained between the individual scores given by the SMD (0.870 to 0.970). The automatic prediction of MDS-UPDRS scores using the proposed system may be valuable in clinical trials designed to evaluate and modify motor disability in PD patients.
Collapse
|
18
|
The usefulness of accelerometric registration with assessment of tremor parameters and their symmetry in differential diagnosis of parkinsonian, essential and cerebellar tremor. Neurol Neurochir Pol 2012; 46:145-56. [DOI: 10.5114/ninp.2012.28257] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
19
|
Machowska-Majchrzak A, Pierzchała K, Pietraszek S, Labuz-Roszak B. Essential tremor - assessment of tremor accelerometric parameters' symmetry and the relationship between hand dominance and severity of tremor. Neurol Neurochir Pol 2011; 45:121-7. [PMID: 21574115 DOI: 10.1016/s0028-3843(14)60022-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE Essential tremor (ET) is likely the most common movement disorder. The aim of the study was to carry out spectral analysis of the essential tremor recorded by an accelerometer and assess the symmetry of tremor parameters between the two hands. MATERIAL AND METHODS We examined 39 patients with ET diagnosed clinically using the criteria of the Movement Disorder Society. The control group consisted of 52 healthy persons. A biaxial accelerometer mounted at the dorsal side of the hand was used. Spectral analysis was performed. Tremor intensity, frequency of spectral peaks, centre frequency, standard deviation of the centre frequency, and harmonic index were measured. The side-to-side symmetry of these parameters was analysed. The relationship of hand dominance and severity of tremor was also analysed. RESULTS There was significant side-to-side asymmetry of intensity in ET. The intensity in the more affected hand was over two times higher than that in the less affected one. The tremor was more severe in the nondominant hand in 62% of patients. In spite of significant difference in tremor intensity between the two sides, tremor frequency was similar in both hands. The standard deviation of centre frequency was significantly lower and the harmonic index was significantly higher in the more trembling hand. CONCLUSIONS Accelerometric registration revealed that asymmetry of intensity and symmetry of frequency are characteristic features of ET. The remaining two coefficients reflecting the rhythmicity and regularity of tremor also differed considerably between the hands.
Collapse
Affiliation(s)
- Agnieszka Machowska-Majchrzak
- Katedra i Klinika Neurologii Śląskiego Uniwersytetu Medycznego w Katowicach, Wydział Lekarski z Oddziałem Lekarsko-Dentystycznym w Zabrzu, ul. 3 Maja 13/15, 41-800 Zabrze.
| | | | | | | |
Collapse
|
20
|
Palmes P, Ang WT, Widjaja F, Tan LCS, Au WL. Pattern mining of multichannel sEMG for tremor classification. IEEE Trans Biomed Eng 2010; 57:2795-805. [PMID: 20851786 DOI: 10.1109/tbme.2010.2076810] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Tremor is defined as the involuntary rhythmic or quasi-rhythmic oscillation of a body part, resulting from alternating or simultaneous contractions of antagonistic muscle groups. While tremor may be physiological, those who have disabling pathological tremors find that performing typical activities for daily living to be physically challenging and emotionally draining. Detecting the presence of tremor and its proper identification are crucial in prescribing the appropriate therapy to lessen its deleterious physical, emotional, psychological, and social impact. While diagnosis relies heavily on clinical evaluation, pattern analysis of surface electromyogram (sEMG) signals can be a useful diagnostic aid for an objective identification of tremor types. Using sEMG system attached to several parts of the patient's body while performing several tasks, this research aims to develop a classifier system that automates the process of tremor types recognition. Finding the optimal model and its corresponding parameters is not a straightforward process. The resulting workflow, however, provides valuable information in understanding the interplay and impact of the different features and their parameters to the behavior and performance of the classifier system. The resulting model analysis helps identify the necessary locations for the placement of sEMG electrodes and relevant features that have significant impact in the process of classification. These information can help clinicians in streamlining the process of diagnosis without sacrificing its accuracy.
Collapse
Affiliation(s)
- Paulito Palmes
- Department of Research, National Neuroscience Institute, Singapore.
| | | | | | | | | |
Collapse
|
21
|
Costa J, González HA, Valldeoriola F, Gaig C, Tolosa E, Valls-Solé J. Nonlinear dynamic analysis of oscillatory repetitive movements in Parkinson's disease and essential tremor. Mov Disord 2010; 25:2577-86. [DOI: 10.1002/mds.23334] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
22
|
Papapetropoulos S, Katzen HL, Scanlon BK, Guevara A, Singer C, Levin BE. Objective quantification of neuromotor symptoms in Parkinson's disease: implementation of a portable, computerized measurement tool. PARKINSONS DISEASE 2010; 2010:760196. [PMID: 20976095 PMCID: PMC2957312 DOI: 10.4061/2010/760196] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 04/13/2010] [Accepted: 05/04/2010] [Indexed: 11/20/2022]
Abstract
Quantification of neuromotor symptoms with device-based measures provides a useful supplement to clinical evaluation. Research using the CATSYS has established its utility as a computerized measurement system to quantify neuromotor function. The primary objective of this study is to provide technical guidance on the use of the CATSYS in Parkinson's disease (PD). Forty-four patients with idiopathic PD and 28 healthy controls were prospectively recruited and evaluated with CATSYS, a portable, Windows-based system consisting of a data logger and four different sensors (tremor pen, touch recording plate, reaction time handle, and force plate for balance recording) for quantification of neuromotor functions. CATSYS discriminated between PD and controls on measurements of rest/postural tremor, pronation/supination, finger tapping, simple reaction time, and postural sway intensity and velocity. CATSYS measurements using the proposed test battery were associated with relevant clinician-rated Unified Parkinson's disease rating scale (UPDRS) items assessing tremor and bradykinesia. More work is warranted to establish CATSYS as a diagnostic/monitoring instrument in movement disorders using the proposed technical approaches.
Collapse
|
23
|
Mansur PHG, Cury LKP, Leite JOB, Pereira AA, Penha-Silva N, Andrade AO. The approximate entropy of the electromyographic signals of tremor correlates with the osmotic fragility of human erythrocytes. Biomed Eng Online 2010; 9:29. [PMID: 20569460 PMCID: PMC2895611 DOI: 10.1186/1475-925x-9-29] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 06/22/2010] [Indexed: 03/23/2024] Open
Abstract
BACKGROUND The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics. METHODS This work sought correlations between the osmotic fragility of erythrocytes and features extracted from electromyographic (EMG) activity resulting from physiological tremor in healthy patients (N = 44) at different ages (24-87 years). The osmotic fragility was spectrophotometrically evaluated by the dependence of hemolysis, provided by the absorbance in 540 nm (A54o), on the concentration of NaCl. The data were adjusted to curves of sigmoidal regression and characterized by the half transition point (H50), amplitude of lysis transition (dx) and values of A540 in the curve regions that characterize the presence of lysed (A1) and preserved erythrocytes (A2). The approximate entropy was estimated from EMG signals detected from the extensor carpi ulnaris muscle during the movement of the hand of subjects holding up a laser pen towards an Archimedes spiral, fixed in a whiteboard. The evaluations were carried out with the laser pen at rest, at the center of the spiral, and in movement from the center to the outside and from outside to the center. The correlations among the parameters of osmotic fragility, tremor and age were tested. RESULTS Negative correlations with age were found for A1 and dx. With the hand at rest, a positive correlation with H50 was found for the approximate entropy. Negative correlations with H50 were found for the entropy with the hand in movement, as from the center to the outside or from the outside to the center of the spiral. CONCLUSION In healthy individuals, the increase in the erythrocyte osmotic fragility was associated with a decrease in the approximate entropy for rest tremor and with an increase of the entropy for movement tremor. This suggests that the neuromuscular degeneration associated with tremor entails also the mechanisms involved in the breakdown of structural homeostasis of the erythrocyte membrane.
Collapse
Affiliation(s)
- Paulo HG Mansur
- Biomedical Engineering Laboratory, Faculty of Electrical Engineering, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38.408-100, Brazil
| | - Lacordaire KP Cury
- Biomedical Engineering Laboratory, Faculty of Electrical Engineering, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38.408-100, Brazil
| | - José OB Leite
- Institute of Genetics and Biochemistry, Federal University of Uberlândia, Uberlândia, MG, 38400-902, Brazil
| | - Adriano A Pereira
- Biomedical Engineering Laboratory, Faculty of Electrical Engineering, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38.408-100, Brazil
| | - Nilson Penha-Silva
- Institute of Genetics and Biochemistry, Federal University of Uberlândia, Uberlândia, MG, 38400-902, Brazil
| | - Adriano O Andrade
- Biomedical Engineering Laboratory, Faculty of Electrical Engineering, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38.408-100, Brazil
| |
Collapse
|
24
|
Quantitative analysis of motor performance in epilepsy patients treated with valproate. Seizure 2010; 19:173-7. [DOI: 10.1016/j.seizure.2010.01.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 12/18/2009] [Accepted: 01/22/2010] [Indexed: 11/21/2022] Open
|
25
|
Papapetropoulos S, Gallo BV, Guevara A, Singer C, Mitsi G, Lyssikatos C, Jagid JR. Objective tremor registration during DBS surgery for essential tremor. Clin Neurol Neurosurg 2009; 111:376-9. [PMID: 19121890 DOI: 10.1016/j.clineuro.2008.10.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2008] [Revised: 10/19/2008] [Accepted: 10/31/2008] [Indexed: 10/21/2022]
Abstract
Essential Tremor (ET) is characterized by a 4-12-Hz postural and kinetic tremor, most commonly affecting the upper limbs. Deep brain stimulation (DBS) of the thalamus (Vim) has been found to be highly effective in severe/refractory forms of ET. Intra-operative assessment of tremor is performed using clinical methods based on patient and physician perception of tremor intensity. We present for the first time the case of a patient whose tremor was objectively monitored/quantified pre- and intra-operatively using device-based tremor registration to supplement clinical measures. We present the case of a 76-year-old right-handed woman that received unilateral (left-sided) DBS of the ventrointermediate (Vim) nucleus of thalamus (Vim) for medically refractory ET. Tremor was monitored with an accelerometer-based Tremor Pen, which is part of a simple portable device (CATSYS 2000 System, Danish Product Development Ltd., DK, www.catsys.dk). The patient was asked to perform tasks for tremor evaluation before and during thalamic DBS. Tremor quantification revealed a significant improvement (34.7-fold) in the contralateral (right) limb following macro-stimulation. No significant improvement was registered in the ipsilateral (non-operated) side. Simple electronic tremor registration methods during DBS of the Vim nucleus of the thalamus may supplement the existing methodology that is solely based on subjective measures derived from clinical observations.
Collapse
Affiliation(s)
- Spiridon Papapetropoulos
- Division of Movement Disorders, Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, United States.
| | | | | | | | | | | | | |
Collapse
|
26
|
|
27
|
A neurobehavioral study of current and former welders exposed to manganese. Neurotoxicology 2007; 29:48-59. [PMID: 17942157 DOI: 10.1016/j.neuro.2007.08.014] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 08/16/2007] [Accepted: 08/28/2007] [Indexed: 11/21/2022]
Abstract
Neurobehavioral functions were studied in 96 welders currently exposed to the geometric mean (GM) concentration of 121 microg/m(3) (range 7-2322) manganese (Mn) in welding fume (air-Mn) based on the individual mean from two successive days of sampling. They were compared to 96 age-matched referents. The arithmetic mean (AM) concentration of Mn in whole blood (B-Mn) was 8.6 microg/L versus 6.9 microg/L in the referents. Associations between the Digit Symbol and Finger Tapping test scores and B-Mn and air-Mn, respectively, were observed. The welders exposed to the highest air-Mn concentrations (GM 423 microg/m(3) range 204-2322) had statistically significantly poorer Finger Tapping test score as compared to their age-matched referents. The welders with the highest AM concentration of B-Mn (12.6 microg/L) scored statistically significantly poorer on the Digit Symbol test when compared to the age-matched referents (AM B-Mn 7.5 microg/L). The same neurobehavioral test battery was applied to 27 patients diagnosed, and financially compensated, as having welding related manganism. They were on average 44.9 (range 34-51) years old at the time of diagnosis, which on average was 5.8 years prior to this study. They had worked as welders for 23.1 years on average (range 15-30). The most affected neurobehavioral functions were associated with impaired Finger Tapping speed and Grooved Pegboard performance. The patients had no alterations in hand tremor as assessed by the CATSYS system, while a few subjects had noticeable tremor as assessed by the Static Steadiness test.
Collapse
|
28
|
Tamás G, Pálvölgyi L, Takáts A, Szirmai I, Kamondi A. Delayed beta synchronization after movement of the more affected hand in essential tremor. Neurosci Lett 2006; 405:246-51. [PMID: 16901638 DOI: 10.1016/j.neulet.2006.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2006] [Revised: 07/05/2006] [Accepted: 07/08/2006] [Indexed: 10/24/2022]
Abstract
To investigate the pathomechanism of parkinsonian tremor (PT) and essential tremor (ET) by studying the correlation between tremor asymmetry and post-movement beta synchronization (PMBS) of the human EEG. We recorded the EEG of 10 patients with ET, 10 patients with Parkinson's disease and 10 controls. Subjects pressed an on-off switch in a self-paced manner with the thumb of their less (T+) and more (T++) tremulous hand. After digitalization of the EEG from the Cz, C3, C4 electrodes the movement reactive beta frequency, its maximum peak power value and its latency triggered to movement offset were determined. In ET tremor intensity did not influence the power of PMBS, however it was significantly delayed after the movement of the more tremulous hand. In Parkinson's disease after the movement of the more tremulous hand PMBS power was decreased, but it was not delayed. In controls the side of movement had no effect on the power and latency of the PMBS. The neuronal mechanisms underlying PMBS generation are differently affected in essential tremor and Parkinson's disease. The increase of PMBS latency after movement of the more affected hand in ET indicates possible cortical mechanisms in essential tremor generation.
Collapse
Affiliation(s)
- Gertrúd Tamás
- Semmelweis University, Faculty of Medicine, Department of Neurology, Balassa u. 6., 1083 Budapest, Hungary
| | | | | | | | | |
Collapse
|