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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3158-3161, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018675

RESUMO

Surface electromyography (sEMG) of the lower limb muscles has been proposed to evaluate motor dysfunctions in Parkinson's disease (PD) patients. Variability in the sEMG could be used as an indicator of poor muscle coordination, but previous studies have reported conflicting results. This study has examined the variability of muscle using the coefficients of variance of Tibialis anterior (TA) and Medial gastrocnemius (MG) lower limb muscles for 24 PD, 24 age matched controls (CO), and 24 young controls (YC), during different phases of the gait cycle. The gait intervals were measured using the inertial measurement unit (IMU). We observed a statistically significant difference between PD and control for the variability of lower limb muscle when comparing the sub-phases of the gait. It was also found that the difference was more pronounced for the TA muscle.


Assuntos
Doença de Parkinson , Caminhada , Eletromiografia , Marcha , Humanos , Músculo Esquelético
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3666-3669, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018796

RESUMO

This study has investigated the efficiency of voice features in estimating the motor Unified Parkinson's Disease Rating Scale (UPDRS) score in Parkinson's disease (PD) patients. A total of 26 PD patients (mean age = 72) and 22 control subjects (mean age = 66.91) were recruited for the study. The sustained phonation /a/, /u/ and /m/ were collected in both off-state and on-state of Levodopa medication. The average motor UPDRS for PD off-state patients was 27.31, on-state was 20.42 and that of controls was 2.63. Voice features were extracted from the phonation tasks and were reduced to the most relevant 6 features for each phonation task using the Least Absolute Shrinkage and Selection Operator (LASSO) feature ranking method. The correlation between the reduced features and motor UPDRS was tested using the Spearman correlation coefficient test. AdaBoost regression learner was trained and used for automatically estimating the motor UPDRS score using the voice features. The results show that the vocal features for /m/ performed best by estimating the motor UPDRS score for PD off-state with the mean absolute error (MAE) of 3.52 and 5.90 for PD on-state. This study shows that assessment of voice can be used for day to day remote monitoring of PD patients.


Assuntos
Doença de Parkinson , Voz , Humanos , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Fonação
3.
Biosensors (Basel) ; 10(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861890

RESUMO

In this paper, we have investigated the differences in the voices of Parkinson's disease (PD) and age-matched control (CO) subjects when uttering three phonemes using two complexity measures: fractal dimension (FD) and normalised mutual information (NMI). Three sustained phonetic voice recordings, /a/, /u/ and /m/, from 22 CO (mean age = 66.91) and 24 PD (mean age = 71.83) participants were analysed. FD was first computed for PD and CO voice recordings, followed by the computation of NMI between the test groups: PD-CO, PD-PD and CO-CO. Four features reported in the literature-normalised pitch period entropy (Norm. PPE), glottal-to-noise excitation ratio (GNE), detrended fluctuation analysis (DFA) and glottal closing quotient (ClQ)-were also computed for comparison with the proposed complexity measures. The statistical significance of the features was tested using a one-way ANOVA test. Support vector machine (SVM) with a linear kernel was used to classify the test groups, using a leave-one-out validation method. The results showed that PD voice recordings had lower FD compared to CO (p < 0.008). It was also observed that the average NMI between CO voice recordings was significantly lower compared with the CO-PD and PD-PD groups (p < 0.036) for the three phonetic sounds. The average NMI and FD demonstrated higher accuracy (>80%) in differentiating the test groups compared with other speech feature-based classifications. This study has demonstrated that the voices of PD patients has reduced FD, and NMI between voice recordings of PD-CO and PD-PD is higher compared with CO-CO. This suggests that the use of NMI obtained from the sample voice, when paired with known groups of CO and PD, can be used to identify PD voices. These findings could have applications for population screening.


Assuntos
Técnicas Biossensoriais , Doença de Parkinson/diagnóstico , Máquina de Vetores de Suporte , Voz , Idoso , Humanos , Fonética
4.
Front Neurol ; 10: 403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068893

RESUMO

Progressive micrographia is decrement in character size during writing and is commonly associated with Parkinson's disease (PD). This study has investigated the kinematic features of progressive micrographia during a repetitive writing task. Twenty-four PD patients with duration since diagnosis of <10 years and 24 age-matched controls wrote the letter "e" repeatedly. PD patients were studied in defined off states, with scoring of motor function on the Unified Parkinson's Disease Rating Scale Part III. A digital tablet captured x-y coordinates and ink-pen pressure. Customized software recorded the data and offline analysis derived the kinematic features of pen-tip movement. The average size of the first and the last five letters were compared, with progressive micrographia defined as >10% decrement in letter stroke length. The relationships between dimensional and kinematic features for the control subjects and for PD patients with and without progressive micrographia were studied. Differences between the initial and last letter repetitions within each group were assessed by Wilcoxon signed-rank test, and the Kruskal-Wallis test was applied to compare the three groups. There are five main conclusions from our findings: (i) 66% of PD patients who participated in this study exhibited progressive micrographia; (ii) handwriting kinematic features for all PD patients was significantly lower than controls (p < 0.05); (iii) patients with progressive micrographia lose the normal augmentation of writing speed and acceleration in the x axis with left-to-right writing and show decrement of pen-tip pressure (p = 0.034); (iv) kinematic and pen-tip pressure profiles suggest that progressive micrographia in PD reflects poorly sustained net force; and (v) although progressive micrographia resembles the sequence effect of general bradykinesia, we did not find a significant correlation with overall motor disability, nor with the aggregate UPDRS-III bradykinesia scores for the dominant arm.

5.
Biosensors (Basel) ; 9(2)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027153

RESUMO

This study investigated the difference in the gait of patients with Parkinson's disease (PD), age-matched controls and young controls during three walking patterns. Experiments were conducted with 24 PD, 24 age-matched controls and 24 young controls, and four gait intervals were measured using inertial measurement units (IMU). Group differences between the mean and variance of the gait parameters (stride interval, stance interval, swing interval and double support interval) for the three groups were calculated and statistical significance was tested. The results showed that the variance in each of the four gait parameters of PD patients was significantly higher compared with the controls, irrespective of the three walking patterns. This study showed that the variance of any of the gait interval parameters obtained using IMU during any of the walking patterns could be used to differentiate between the gait of PD and control people.


Assuntos
Marcha , Doença de Parkinson/fisiopatologia , Idoso , Algoritmos , Fenômenos Biomecânicos , Estudos de Casos e Controles , Interpretação Estatística de Dados , Feminino , Humanos , Masculino
6.
J Neurol ; 266(6): 1376-1382, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877380

RESUMO

Levodopa treatment does improve Parkinson's disease (PD) dysgraphia, but previous research is not in agreement about which aspects are most responsive. This study investigated the effect of levodopa on the kinematics of writing. Twenty-four patients with PD of less than 10 years duration and 25 age-matched controls were recruited. A practically defined off state method was used to assess the levodopa motor response, measured on the Unified Parkinson's Disease Rating Scale Part III. The kinematic features for six handwriting tasks involving different levels of complexity were recorded from PD patients in off and on states and from the control group. Levodopa is effective for simple writing activities involving repetition of letters, denoting improved fine motor control. But the same benefit was not seen for copying a sentence and a written category fluency test, tasks that carry memory and cognitive loads. We also found significant differences in kinematic features between control participants and PD patients, for all tasks and in both on and off states. Serial testing of handwriting in patients known to be at risk for developing PD might prove to be an effective biomarker for cell loss in the substantia nigra and the associated dopamine deficiency. We recommend using a panel of writing tasks including sentence copying and memory dependence. Dual-task effects may make these activities more sensitive to early motor deficits, while their weaker levodopa responsiveness would cause them to be more stable indicators of motor progression once symptomatic treatment has been commenced.


Assuntos
Agrafia/tratamento farmacológico , Dopaminérgicos/farmacologia , Levodopa/farmacologia , Destreza Motora/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Idoso , Agrafia/etiologia , Fenômenos Biomecânicos , Feminino , Escrita Manual , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações
7.
IEEE J Biomed Health Inform ; 22(5): 1648-1652, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29028217

RESUMO

BACKGROUND: Change of handwriting can be an early marker for severity of Parkinson's disease but suffers from poor sensitivity and specificity due to inter-subject variations. AIM: This study has investigated the group-difference in the dynamic features during sketching of spiral between PD and control subjects with the aim of developing an accurate method for diagnosing PD patients. METHOD: Dynamic handwriting features were computed for 206 specimens collected from 62 Subjects (31 Parkinson's and 31 Controls). These were analyzed based on the severity of the disease to determine group-difference. Spearman rank correlation coefficient was computed to evaluate the strength of association for the different features. RESULTS: Maximum area under ROC curve (AUC) using the dynamic features during different writing and spiral sketching tasks were in the range of 0.67 to 0.79. However, when angular features ($\boldsymbol{\varphi }$ and ${\boldsymbol{p}_{\boldsymbol{n}}}$) and count of direction inversion during sketching of the spiral were used, AUC improved to 0.933. Spearman correlation coefficient was highest for ϕ and ${\boldsymbol{p}_{\boldsymbol{n}}}$. CONCLUSION: The angular features and count of direction inversion which can be obtained in real-time while sketching the Archimedean guided spiral on a digital tablet can be used for differentiating between Parkinson's and healthy cohort.


Assuntos
Escrita Manual , Destreza Motora/fisiologia , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Doença de Parkinson/classificação
9.
Front Neurol ; 8: 435, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28932206

RESUMO

The speed and pen-pressure while sketching a spiral are lower among Parkinson's disease (PD) patients with higher severity of the disease. However, the correlation between these features and the severity level (SL) of PD has been reported to be 0.4. There is a need for identifying parameters with a stronger correlation for considering this for accurate diagnosis of the disease. This study has proposed the use of the Composite Index of Speed and Pen-pressure (CISP) of sketching as a feature for analyzing the severity of PD. A total of 28 control group (CG) and 27 PD patients (total 55 participants) were recruited and assessed for Unified Parkinson's Disease Rating Scale (UPDRS). They drew guided Archimedean spiral on an A3 sheet. Speed, pen-pressure, and CISP were computed and analyzed to obtain their correlation with severity of the disease. The correlation of speed, pen-pressure, and CISP with the severity of PD was -0.415, -0.584, and -0.641, respectively. Mann-Whitney U test confirmed that CISP was suitable to distinguish between PD and CG, while non-parametric k-sample Kruskal-Wallis test confirmed that it was significantly different for PD SL-1 and PD SL-3. This shows that CISP during spiral sketching may be used to differentiate between CG and PD and between PD SL-1 and PD SL-3 but not SL-2.

10.
Respirology ; 19(4): 531-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24655302

RESUMO

BACKGROUND AND OBJECTIVE: Abnormal vocal cord movement may coexist with asthma and cause additional upper/middle airway obstruction. The condition may be a form of muscular dystonia that could contribute to asthma resistant to optimised treatments. Botulinum toxin causes temporary paralysis of muscle and may be an effective local treatment that improves asthma control. METHODS: In an observational study, we evaluated the benefits of unilateral vocal cord injection with botulinum toxin in 11 patients (total 24 injections). Subjects had asthma resistant to optimised treatment and abnormal vocal cord movement. Responses after botulinum toxin treatment were assessed using asthma control test (ACT) scores, vocal cord narrowing quantified by computerised tomography (CT) of the larynx and spirometry. Side-effects were recorded. RESULTS: ACT scores improved overall (9.1 ± 2.4 before and 13.5 ± 4.5 after treatment; difference 4.4 ± 4.2; P < 0.001). There was also an improvement in airway size on CT larynx (time below lower limit of normal at baseline 39.4 ± 37.63% and improved to 17.6 ± 25.6% after injection; P = 0.032). Spirometry was not altered. One patient experienced an asthma exacerbation but overall side-effects were moderate, chiefly dysphonia and dysphagia. CONCLUSIONS: Although a placebo effect cannot be ruled out, local injection of botulinum toxin may be an effective treatment for intractable asthma associated with abnormal vocal cord movement. Further mechanistic studies and a double-blind randomised controlled trial of botulinum toxin treatment are merited.


Assuntos
Antiasmáticos/uso terapêutico , Asma , Toxinas Botulínicas , Disfunção da Prega Vocal , Prega Vocal/efeitos dos fármacos , Inibidores da Liberação da Acetilcolina/administração & dosagem , Inibidores da Liberação da Acetilcolina/efeitos adversos , Idoso , Asma/complicações , Asma/diagnóstico , Asma/diagnóstico por imagem , Asma/tratamento farmacológico , Asma/fisiopatologia , Toxinas Botulínicas/administração & dosagem , Toxinas Botulínicas/efeitos adversos , Resistência a Medicamentos , Feminino , Humanos , Injeções Intramusculares/métodos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória/métodos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Disfunção da Prega Vocal/complicações , Disfunção da Prega Vocal/diagnóstico , Disfunção da Prega Vocal/tratamento farmacológico , Disfunção da Prega Vocal/fisiopatologia , Prega Vocal/diagnóstico por imagem , Prega Vocal/fisiopatologia
11.
J Parkinsons Dis ; 2(1): 47-55, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23939408

RESUMO

There is a need for objective measures of dyskinesia and bradykinesia of Parkinson's disease (PD) that are continuous throughout the day and related to levodopa dosing. The output of an algorithm that calculates dyskinesia and bradykinesia scores every two minutes over 10 days (PKG: Global Kinetics Corporation) was compared with conventional rating scales for PD in PD subjects. The algorithm recognises bradykinesia as movements made with lower acceleration and amplitude and with longer intervals between movement. Similarly the algorithm recognises dyskinesia as having movements of normal amplitude and acceleration but with shorter periods without movement. The distribution of the bradykinesia and dyskinesia scores from PD subjects differed from that of normal subjects. The algorithm predicted the clinical dyskinesia rating scale AIMS with a 95% margin of error of 3.2 units compared with the inter-rater 95% limits of agreement from 3 neurologists of -3.4 to +4.3 units. Similarly the algorithm predicted the UPDRS III score with a margin of error similar to the inter-rater limits of agreement. Improvement in scores in response to changes in medication could be assessed statistically in individual patients. This algorithm provides objective, continuous and automated assessment of the clinical features of bradykinesia and dyskinesia in PD.


Assuntos
Discinesias/diagnóstico , Discinesias/etiologia , Processamento Eletrônico de Dados , Hipocinesia/diagnóstico , Hipocinesia/etiologia , Doença de Parkinson/complicações , Adulto , Algoritmos , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Levodopa/efeitos adversos , Masculino , Doença de Parkinson/tratamento farmacológico , Análise Espectral , Fatores de Tempo
12.
Mov Disord ; 26(8): 1552-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21538524

RESUMO

BACKGROUND: This randomized double blind, placebo-controlled crossover study investigated the antidyskinetic effects of levetiracetam in Parkinson's disease. METHODS: Sixteen participants with levodopa-induced dyskinesia were enrolled. Hourly videotaped dyskinesia assessments scored by the Goetz method and hourly Unified Parkinson's Disease Rating Scale motor subscale scoring were conducted on 1 day at the end of each treatment period. RESULTS: Dyskinesia was slightly less on placebo (P = .26). Patient diary records also showed less dyskinesia on placebo (P = .10). Parkinsonism was a little worse on levetiracetam, at borderline statistical significance (P = .05). CONCLUSIONS: Levetiracetam was well tolerated at doses up to 2000 mg per day, but we did not detect any antidyskinetic properties.


Assuntos
Anticonvulsivantes/uso terapêutico , Discinesia Induzida por Medicamentos/tratamento farmacológico , Piracetam/análogos & derivados , Antiparkinsonianos/efeitos adversos , Estudos Cross-Over , Método Duplo-Cego , Humanos , Levetiracetam , Levodopa/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Piracetam/uso terapêutico , Índice de Gravidade de Doença , Fatores de Tempo , Gravação em Vídeo
14.
J Clin Neurosci ; 14(2): 99-103, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17107801

RESUMO

Warfarin embryopathy is a well-defined manifestation of intrauterine warfarin exposure. The embryopathy phenotype as it relates to the nervous system is broad and poorly recognised. We describe an adult with neurological sequelae of fetal warfarin exposure. We review previous cases with neurological sequelae and discuss the pathogenetic mechanism in light of recent research.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Anticoagulantes/efeitos adversos , Surdez/induzido quimicamente , Osso Nasal/anormalidades , Doenças da Medula Espinal/induzido quimicamente , Varfarina/efeitos adversos , Adulto , Transtornos Cognitivos/induzido quimicamente , Humanos , Masculino , Coluna Vertebral/anormalidades
15.
Neurol India ; 52(2): 197-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15269469

RESUMO

BACKGROUND: Some patients with focal cerebral calcification (FCC) have no seizure or a benign course of epilepsy, whilst others with a similar lesion have uncontrolled epilepsy. AIMS: To look for perilesional hyperintensity, presumed to be indicative of gliosis, around FCC on magnetization transfer (MT) MRI and to correlate seizure outcome with its presence. SETTING AND DESIGN: Case control study. MATERIAL AND METHODS: Fifty-one patients with epilepsy and 30 controls with single calcified cerebral lesion on CT were studied. Clinical and treatment details were noted. EEG and T1, T2, MT and contrast enhanced MRI were done. STATISTICAL ANALYSIS USED: Student's t test. RESULTS: On MT MRI, perilesional gliosis was seen around the focal calcified lesion in 17 (33.3%) patients. None of the controls had perilesional gliosis. The mean monthly seizure frequency was significantly higher in the 17 patients having perilesional gliosis (2.63+1.15) as compared to the 34 patients without it (0.59+0.63; P= 0.0014). Perilesional gliosis was seen in 8 out of 11 (72.7%) patients who were on 2 AEDs and in all 5 (100%) patients who were on 3 or more AEDs. It was present only in 4 (11.4%) out of 35 patients who were on one AED. CONCLUSION: Gliosis around a cerebral calcified lesion as seen on T1 weighted MT MRI indicates poor seizure control.


Assuntos
Encefalopatias/diagnóstico , Encefalopatias/etiologia , Calcinose/diagnóstico , Calcinose/etiologia , Epilepsia/complicações , Epilepsia/diagnóstico , Imagem por Ressonância Magnética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Epilepsia/fisiopatologia , Feminino , Gliose/diagnóstico , Gliose/etiologia , Humanos , Masculino
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