Roongroj Bhidayasiri

King Chulalongkorn Memorial Hospital, Siayuthia, Bangkok, Thailand

Are you Roongroj Bhidayasiri?

Claim your profile

Publications (129)258.27 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Most Parkinson's disease patients will receive levodopa therapy, and of these, the majority will develop some levodopa-induced complications. For many patients, the first complication to develop is the decline in the duration of therapeutic benefit of each levodopa dose, a phenomenon commonly termed 'wearing-off'. There is already extensive literature documenting the epidemiology and management of wearing-off in Parkinson's disease patients of western descent. However, data derived from these studies might not always apply to patients of Asian descent due to genetic variations, differences in co-morbidities or non-availability of certain drugs. This review summarizes the current literature regarding the epidemiology of wearing-off in Asian (including Arab) patients and discusses the management issues in the context of drug availability in Asia.
    Expert Review of Neurotherapeutics 09/2015; DOI:10.1586/14737175.2015.1088783 · 2.78 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: About 50 % of Thai patients with adult-onset spinocerebellar ataxia (SCA) was Machado-Joseph disease (MJD), SCA1, SCA2 and SCA6. The author investigated further on less common SCAs in the patients without any known mutations. Methods: DNA samples of 82 index patients who were genetically excluded MJD, SCA1, SCA2, SCA6, SCA7 and dentatorubro-pallidoluysian atrophy (DRPLA) were examined. Analysis of SCA8, SCA10, SCA12, SCA17 and SCA19 genes were comprehensively performed. Normal range of trinucleotide repeat expansion sizes of TATA-box-binding protein gene (TBP) were also determined in 374 control subjects. Results: Eight patients carried ≥42 CAG/CAA repeat allele in the TBP consistent with SCA17. The pathological repeat alleles ranged from 42 to 57 repeats. All patients had significant degree of cognitive dysfunction. Other non-ataxic phenotypes comprised of parkinsonism, chorea, dystonia and myoclonus. A sporadic patient carried a heterozygous 41-repeat allele developed chronic progressive cerebellar degeneration commenced at the age of 28 years. Whilst, 2 % of the control subjects (8/374) carried the 41-repeat allele. Five of the carriers were re-examined, and revealed that four of them had parkinsonism and/or cognitive impairment without cerebellar signs. Analysis of other types of SCAs was all negative. Conclusions: This is the first study of SCA8, SCA10, SCA12, SCA17 and SCA19 in Thais. SCA17 appears to be an important cause of ataxia in Thailand. Although, the pathological cut-off point of the TBP repeat allele remains unclear, the finding suggests that the 41-repeat may be a pathological allele resulting late-onset or mild phenotype. Apart from ataxia, cognitive impairment and parkinsonism may be clinical presentations in these carriers.
    BMC Neurology 09/2015; 15(1):166. DOI:10.1186/s12883-015-0425-y · 2.04 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Treatment of dystonias is generally symptomatic. To produce sufficient therapy effects, therefore, frequently a multimodal and interdisciplinary therapeutic approach becomes necessary, combining botulinum toxin therapy, deep brain stimulation, oral antidystonic drugs, adjuvant drugs and rehabilitation therapy including physiotherapy, occupational therapy, re-training, speech therapy, psychotherapy and sociotherapy. This review presents the recommendations of the IAB-Interdisciplinary Working Group for Movement Disorders Special Task Force on Interdisciplinary Treatment of Dystonia. It reviews the different therapeutic modalities and outlines a strategy to adapt them to the dystonia localisation and severity of the individual patient. Hints to emerging and future therapies will be given.
    Journal of Neural Transmission 09/2015; DOI:10.1007/s00702-015-1453-x · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: As the pathophysiology of tremor in Parkinson disease (PD) involves a complex interaction between central and peripheral mechanisms, we propose that modulation of peripheral reflex mechanism by electrical muscle stimulation (EMS) may improve tremor temporarily. Objectives: To determine the efficacy of EMS as a treatment for drug resistant tremor in PD patients. Methods: This study was a single-blinded, quasi-experimental study involving 34 PD patients with classic resting tremor as confirmed by tremor analysis. The EMS was given at 50Hz over the abductor pollicis brevis and interrosseus muscles for 10s with identified tremor parameters before and during stimulation as primary outcomes. Results: Compared to before stimulation, we observed a significant reduction in the root mean square (RMS) of the angular velocity (p<0.001) and peak magnitude (p<0.001) of resting tremor while tremor frequency (p=0.126) and dispersion (p=0.284) remained unchanged during stimulation. The UPDRS tremor score decreased from 10.59 (SD=1.74) before stimulation to 8.85 (SD=2.19) during stimulation (p<0.001). The average percentage of improvement of the peak magnitude and RMS angular velocity was 49.57% (SD=38.89) and 43.81% (SD=33.15) respectively. 70.6% and 61.8% of patients experienced at least 30% tremor attenuation as calculated from the peak magnitude and RMS angular velocity respectively. Conclusions: Our study demonstrated the efficacy of EMS in temporarily improving resting tremor in medically intractable PD patients. Although tremor severity decreased, they were not completely eliminated and continued with a similar frequency, thus demonstrating the role of peripheral reflex mechanism in the modulation of tremor, but not as a generator. EMS should be further explored as a possible therapeutic intervention for tremor in PD.
    Journal of the neurological sciences 09/2015; DOI:10.1016/j.jns.2015.08.1527 · 2.47 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: "Home" is where one has a sense of belonging and feels secure, but it can also be a risky place for people with Parkinson's disease (PD). PD patients need assistance making adjustments to their physical environment to maintain appropriate care and provide a safe environment. This relationship is called the "person-environmental fit" (P-E fit). While most PD patients remain in their own homes, little is known about the specific challenges that PD patients and their caregivers encounter in the routine activities of daily living. The aim of our study was to identify the existing evidence on the issue of housing environmental adaptation in PD by performing a systematic review with a proposal of development strategies to integrate a multidisciplinary team into a home environmental research. MEDLINE, and life science journals were searched by querying appropriate key words, but revealed very few publications in this area. However, early evidence suggested that PD patients do not enjoy an adequate P-E fit in their own homes and face more functional limitations compared to matched controls. We concluded that we need to develop research-based evaluation strategies that can provide us with a theoretical and conceptual basis as well as tools for analysis of the P-E fit for PD patients and caregivers. We recommend that individual members of the multidisciplinary team including patients, caregivers, physicians, rehabilitation specialists, and social workers use a team approach to identify the key indicators and solutions for the development of PD-specific solutions for improving the P-E fit.
    Parkinsonism & Related Disorders 08/2015; DOI:10.1016/j.parkreldis.2015.08.025 · 3.97 Impact Factor
  • Pattamon Panyakaew · Jirada Sringean · Roongroj Bhidayasiri
    [Show abstract] [Hide abstract]
    ABSTRACT: Corresponding author at: Chulalongkorn Center of Excellence on Parkinson Disease & Related Disorders, Chulalongkorn University Hospital, 1873 Rama 4 Road, Bangkok 10330, Thailand. Tel.: +662 256 4000x2501; fax: +662 256 4630.
    Clinical neurology and neurosurgery 07/2015; 137:102-104. DOI:10.1016/j.clineuro.2015.07.001 · 1.13 Impact Factor
  • Pattamon Panyakaew · Chanawat Anan · Roongroj Bhidayasiri
    [Show abstract] [Hide abstract]
    ABSTRACT: Postural instability is often experienced in the late stages of PD and is a marker of disease progression. Little information is available on the role of visual inputs as an adaptive strategy to compensate for postural instability in PD. The purpose of this study was to determine visual dependency for postural control in early PD. Thirty early PD subjects without postural complaints and 30 matched controls were evaluated for subtle postural instability using static posturography under eyes opened and eyes closed conditions. No significant differences between groups were observed under eyes opened condition. In eyes closed condition, there was significantly greater mean sway in the mediolateral direction (p=0.01), mean sway velocity (p=0.03), lateral sway velocity (p=0.04), and sway area (p=0.04) in PD than in the control subjects. 95% confidence ellipse of mean sway was largest in PD patients with eyes closed. A strong and significant correlation was observed between disease duration and mean mediolateral sway, sway area, mean sway and lateral sway velocity, and a moderate correlation was shown between Hoehn & Yahr stage and mean mediolateral sway, and sway area. Our findings suggest that visual dependency exists in early PD and visual deprivation task can help identify subclinical postural instability. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of the Neurological Sciences 01/2015; 349(1-2). DOI:10.1016/j.jns.2015.01.022 · 2.47 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The development of secondary non-response (SNR) to botulinum neurotoxin type-A (BoNT-A) is considered a key issue in the management of cervical dystonia (CD). This case-controlled study was performed to systematically identify factors influencing SNR during BoNT-A therapy.Methods This was a retrospective, international, non-interventional study of CD patients. Patients with SNR were matched with up to three responder patients (control) on the basis of duration of therapy and number of injection cycles. Factors influencing the development of SNR were screened using a univariate logistic regression model and confirmed using a multivariate conditional logistic regression model.Results216 patients were enrolled, and 201 (SNR=52; responder=149) were matched and subdivided into blocks (doublets, triplets or quadruplets). At baseline, a significantly higher proportion of SNR patients had received previous or concomitant therapies (p=0.038) and surgery for CD (p=0.007) compared with controls. Although disease severity at onset was similar between groups, a significantly higher proportion of SNR patients experienced severe CD at the time of SNR compared with controls at the last documented visit. Multivariate analyses identified five factors that were significantly associated in predicting SNR (odds ratio [OR]>1 indicated higher chances for being SNR): previous surgical procedure for CD (OR 9.8, p=0.013), previous BoNT-A related severe adverse event (AE) (OR 5.6 p=0.027), physical therapy (OR 4.6, p=0.028), neuroleptic use (OR 3.3, p=0.019) and average BoNT-A dose (OR 2.7, p=0.010).Conclusions These findings suggest that SNR may not reflect true pharmacological resistance to BoNT-A therapy, but may be related to underlying disease severity.
    Parkinsonism & Related Disorders 11/2014; 21(2). DOI:10.1016/j.parkreldis.2014.09.034 · 3.97 Impact Factor
  • Onanong Jitkritsadakul · Priya Jagota · Roongroj Bhidayasiri
    [Show abstract] [Hide abstract]
    ABSTRACT: To determine the prevalence and predictors of sexual dysfunction (SD) in Parkinson's disease (PD) patients.Background Assessments of SD in the professional literature is limited. Understanding the predictors of SD can help physicians focus on this problem in vulnerable patients.MethodA total of 60 PD patients and 60 controls answered the Arizona Sexual Experiences Scale-Thai Version (ASEX-Thai) and the Hamilton Depression Rating Scale (HAMD) questionnaires, and were asked on 3 additional sets of questions about premature ejaculation (PE), dyspareunia, and hypersexual disorders.ResultThe prevalence of SD in PD patients and controls was 81.6% and 48.3% respectively (p < 0.05). PD patients had lower BMI, lower uric acid level, higher HAMD score and had sexual intercourse (SI) less frequently. SD correlated with greater disease severity and depression. The most distressing problem in male patients was PE (51.4%) and orgasmic dissatisfaction (76%) for female patients. Logistic regression analysis found 3 factors were related to SD: no SI in the past month (p < 0.001), postural instability (PI) (p = 0.028), and HAMD item 14 (p = 0.021), predicting SD with the OR of 12.2, 5.5, and 5.0 respectively.ConclusionsSD in PD is common and usually occurs with depression. Absence of SI in the past month, PI, and loss of libido are predictors of SD in PD. A simple and quick screening of SD can be routinely performed by inquiring patients about the frequency of SI and the examination of the pull test. Detailed assessment of sexual functioning and depression may guide physicians in proper management.
    Parkinsonism & Related Disorders 11/2014; 21(1). DOI:10.1016/j.parkreldis.2014.11.003 · 3.97 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Blepharoclonus refers to myoclonic rhythmic eyelid closure. This is an extremely rare abnormal movement of the eyelids. The symptom has an ill-defned anatomical localization and hypothesized etiologies are diverse. We describe a 42 year-old woman with known poorly controlled hypertension (HTN) who presented with a three-week history ofataxia, dysmetria, and uncontrolled eyelid twitching. The bilateral abnormal eyelid movement occurred during either eyelid closure or opening, and was compatible with blepharoclonus. MRI revealed multiple cerebral infarctions at red nucleus, dentate nucleus, and inferior olives. These foci are within Guillain-Mollaret's triangle. The ataxia and dysmetria gradually improved within three weeks. While the blepharoclonus improved, it persisted after one year offollow-up. Our conclusion was one of HTN leading to a lacunar infarct that manifested partially as blepharoclonus. Due to the neuroimaging findings and clinical course, we propose that blepharoclonus may be a variant ofpalatal myoclonus and may be considered as another lacunar syndrome.
    Journal of the Medical Association of Thailand = Chotmaihet thangphaet 09/2014; 97(9):977-81.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although Dr. James Parkinson wrote his classic essay The Shaking Palsy almost 200 years ago to inform the scientific and medical communities about the disease that now bears his name, the fundamental dynamics of Parkinson disease (PD) are still not fully understood.(1) Perhaps because the criteria for diagnosing PD all relate to movements, many people, including physicians, have the misconception that PD primarily is a movement disorder when, in fact, it has a great impact on many other physical and psychological functions as well. In light of the absence of a definitive understanding of the basic etiology of PD and the comprehensive scope of its impact, the medical responses to this neurodegenerative disease often are influenced by misconceptions based on myths and false assumptions.
    Neurology 06/2014; 82(24):2238-2240. DOI:10.1212/WNL.0000000000000515 · 8.29 Impact Factor
  • Source
    Roongroj Bhidayasiri · Onanong Jitkritsadakul · Carlo Colosimo
    [Show abstract] [Hide abstract]
    ABSTRACT: Although nocturnal disturbances are increasingly recognized as an integral part of the continuum of daytime manifestations of Parkinson's disease (PD), there is still little evidence in the medical literature to support the occurrence of these complex phenomena in patients with atypical parkinsonian disorders (APDs). Based on the anatomical substrates in APDs, which are considered to be more extensive outside the basal ganglia than in PD, we might expect that patients with APDs encounter the whole range of nocturnal disturbances, including motor, sleep disorders, autonomic dysfunctions, and neuropsychiatric manifestations at a similar, or even greater, frequency than in PD. This article is a review of the current literature on the problems at nighttime of patients with progressive supranuclear palsy, multiple system atrophy, corticobasal degeneration, and dementia with Lewy bodies. MEDLINE, life science journals and online books were searched by querying appropriate key words. Reports were included if the studies were related to nocturnal manifestations in APDs. Forty articles fulfilled the selection criteria. Differences between these symptoms in APDs and PD are highlighted, given the evidence available about each manifestation. This analysis of nocturnal manifestations of APDs suggests the need for future studies to address these issues to improve the quality of life not only of patients with APDs but the caregivers who encounter the challenges of supporting these patients on a daily basis.
    04/2014; 4(2). DOI:10.3233/JPD-130280
  • Priya Jagota · Angela Vincent · Roongroj Bhidayasiri
    [Show abstract] [Hide abstract]
    ABSTRACT: A confused and agitated 18-year-old woman presented to the emergency unit with orolingual movements, eye deviation, and a temperature of 38°C. The symptoms had begun 2 weeks prior to the admission when she developed a severe headache associated with pathologic laughing and intermittent episodes of upgaze deviation. A urine pregnancy test was positive and a transvaginal ultrasonography showed a 9-week-old fetus. An MRI of the brain was unremarkable and results of the CSF analysis were also unremarkable apart from a CSF pleocytosis (62 lymphocytes) and slightly elevated protein (55 mg/dL; normal range 0-45 mg/dL). Extensive microbiologic and serologic studies with CSF were all negative. She gradually lost consciousness, experienced respiratory failure, and was intubated. There were semirhythmic movements consisting of complex patterns of mouth opening, chewing, facial grimacing, synchronous flexion-extension, and supination-pronation limb movements, which persisted during the period of unresponsiveness. She also had generalized hyperreflexia, persistent hyperthermia, and a full bladder. Three EEGs showed diffuse slow waves with no epileptic discharges. A diagnosis of anti-NMDA receptor (NMDAR) encephalitis was made on clinical grounds and strongly positive serum NMDAR antibodies.
    Neurology 04/2014; 82(18). DOI:10.1212/WNL.0000000000000384 · 8.29 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Parkinson's disease (PD) imposes a burden on those who care for the person afflicted. The objective of this study was to assess and analyze the main determinants of caregivers' burden, especially the nocturnal manifestations of PD. This multi-center, national, cross-sectional study included 89 patient-caregiver pairs. Caregiver self-assessments were performed with Hospital Anxiety and Depression Scale (HADS) and Zarit Caregiver Burden Interview (ZCBI). Patient self-assessments were performed with Modified Parkinson's Disease Sleep Scale (MPDSS), Nocturnal Akinesia Dystonia and Cramp Score (NADCS), HADS and Parkinson's Disease Quality of Life Questionnaire (PDQ-8). Most of the caregivers were employed women, and the majority had been permanently taking care of the patient for 6.8 ± 5.4 years. The study found that the ZCBI mean score of the caregivers significantly worsened as patients became more dependent (HY: 4-5, p = 0.036), and the mean ZCBI score of spousal caregivers (19.4; SD 15.5) was significantly higher than that of the offspring group (11.7; SD 7.9) (p = 0.008). Disease duration (r = 0.22), NADCS (r = 0.38), MPDSS (r = -0.36), PDQ-8 SI (r = 0.39) and HADS (total, anxiety and depression) scores (r = 0.46-0.49), and HADS (total, anxiety and depression scores (r = 0.37-0.52), had significant negative effect on caregivers' burden. Moderate association was found on MPDSS item 14 (r = 0.38) and NADCS akinesia score (r = 0.37). Patients' anxiety, nocturnal akinesia and the feeling of tiredness and sleepiness upon awakening in the morning were independent predictors of caregivers' burden (adjusted R (2) = 0.46). Based on these findings, treatment of early mood symptoms of the patients and caregivers at risk may be helpful for the effective management of PD and it is also important to have well-designed psycho-educational and multicomponent interventions in the community for caregivers of persons with PD.
    Journal of Neural Transmission 03/2014; 121(S1). DOI:10.1007/s00702-014-1200-8 · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Nocturnal manifestations of Parkinson's disease (PD) are myriad, have diverse etiologies and include motor, sleep, urinary, and neuropsychiatric symptoms which are often associated with daytime somnolence. While most patients perceive these symptoms as troublesome, the recognition of nocturnal problems related to PD is still low in clinical practice. We conducted a survey using semi-structured interviews and self-rated questionnaires of 215 consecutive patients with PD enrolled in three centers in Thailand to determine the prevalence and risk factors of nocturnal disabilities and their relationship to daytime symptoms. We found that 96.6 % of patients reported the presence of nocturnal symptoms as determined by the modified version of Parkinson's Disease Sleep Scale (MPDSS). Our survey indicated that the most frequent and distressing symptom was the interruption of sleep to pass urine (56.7 %, 4.4 ± 3.9). The severity of symptoms revealed in the MPDSS increased along with the disease duration (p < 0.05) and Hoehn and Yahr stages (p = 0.01). There were similar to findings of the Nocturnal Akinesia Dystonia and Cramp Score (NADCS) where patients with advanced disease had significantly higher NADCS scores than early/moderate disease (p < 0.001). There was a significant correlation of total MPDSS scores with the total scores of the 9-item Wearing-Off Questionnaire (WOQ-9); (r = -0.43, p < 0.05) [motor (r = -0.35, p < 0.05) and nonmotor subscores (r = -0.43, p < 0.05)]; total nonmotor symptoms (NMS) scores (r = -0.55, p < 0.05); Parkinson's Disease Questionnaire-8 Summary Index (PDQ-8 SI) (r = -0.52, p < 0.05); and the total NADCS (r = -0.35, p < 0.05). Multiple regression analysis identified PDQ-8 SI (β = -0.27, p = 0.005) as the most significant predictor of nocturnal manifestations of PD, followed by the nonmotor subscore of WOQ (β = -0.24, p = 0.006), and the NMS item 20 (feeling light-headed, dizzy, or weak when standing from sitting or lying) (β = -0.22, p = 0.003). Our study found that nocturnal symptoms of PD are very common and we suggest that good clinical practice should include a comprehensive review of nighttime manifestations, particularly for those patients who already experience "wearing-off" symptoms.
    Journal of Neural Transmission 03/2014; 121. DOI:10.1007/s00702-014-1199-x · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: While nocturnal disturbances of Parkinson's disease (PD) are increasingly recognized as being part of a continuum that includes daytime manifestations, there is still little analysis in the medical literature that assesses these complex phenomena in patients with atypical (AP) and vascular parkinsonisms (VP). The objective of our study was to determine the prevalence of these disturbances in patients with AP and VP and to determine the range of nighttime symptoms that occur compared with those in patients with PD. This comparison was done using a semi-structured interview and self-rated questionnaires in 63 AP and VP patients (PSP 24, MSA 24, CBD 5, and VP 10), and 208 PD patients. 61 AP and VP patients (96.8 %) and 201 PD patients (96.6 %) reported at least one nocturnal symptom with a score of less than 6 on the Modified Parkinson's Disease Sleep Scale (MPDSS). Nocturnal akinesia, as measured on the Nocturnal Akinesia, Dystonia, and Cramp Score, was found to be significantly greater in patients with PSP (p = 0.006), MSA (p = 0.002), and CBD (p = 0.012) than PD patients, but not VP patients (p = 0.428). Like those with PD, patients with AP and VP identified the problem of getting up at night to urinate (MPDSS item 8) as being the most frequent and troublesome nocturnal symptom. MSA and PSP patients reported more frequent (p = 0.001) and troublesome (p < 0.001) urinary incontinence (MPDSS item 9) than PD patients and MSA patients had more severe problems with unexpectedly falling asleep during the day (MPDSS item 15) than PD patients (p = 0.003). In summary, our study determined that nocturnal manifestations are commonly experienced by patients with AP and VP and highlighted specific nocturnal symptoms, which are more prevalent and troublesome in certain AP syndromes. The concept of 24-h control of symptoms should not be limited to only PD and we recommend that all who are involved in the care of AP and VP patients should realize that many nocturnal symptoms are experienced by these patients and a multidisciplinary approach should be utilized to address these problems.
    Journal of Neural Transmission 03/2014; 121. DOI:10.1007/s00702-014-1198-y · 2.40 Impact Factor
  • Heinz Reichmann · Roongroj Bhidayasiri
    Journal of Neural Transmission 03/2014; 121(S1). DOI:10.1007/s00702-014-1186-2 · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Tremors are common clinical complaints among the elderly and non-specialist physicians frequently are challenged by the need to provide an accurate diagnosis of various tremor syndromes, particularly Parkinson's disease and essential tremor in their busy practices. Objective: We sought to develop an easy-to-use, mobile robust, accurate, and cost-effective instrument that can objectively quantify tremors. Method: The low-cost, 3-dimension, inertial sensors were developed for automated tremor assessment. The main sensor unit consists of a 3-axis accelerometer and a 3-axis gyroscope for the purpose of measuring the tilting angle relative to the gravity, linear acceleration, and angular velocity of the body segments affected by tremors. The transmitter consists of five main modules, including a microcontroller, power management module, sensor module, external memory interface module, and Bluetooth™ communication interface module, which connects to the sensors by a thin wire. The signal processing utilized fast Fourier transform analysis to include RMS angular rate, RMS angle, RMS rate, RMS velocity, peak frequency, peak frequency magnitude, and dispersion of frequency as variables. Result: The prototype was tested with a tremor simulator at programmable angular rates of 2-, 4-, and 8-Hz confirming its accuracy. Twenty subjects (10 PD and 10 age-matched ET patients) participated as part of the experimental verification to perform three tremor tasks, including rest, postural, and kinetic tremor according to the teaching videotape of the motor section of the UPDRS. The mean peak frequency was significantly lower in PD than ET patients at rest on the x- (p < 0.01) and z-axis (p < 0.01). In PD patients, the RMS angular rate, RMS angle, RMS rate, RMS velocity, and peak magnitude were all significantly higher than those values in ET patient at rest while the data was not significantly difference during postural and kinetic actions. ET patients had significantly higher peak frequency during postural action in the y-axis than PD patients (p < 0.05). Conclusion: The study provides the technical development of an accurate, inexpensive, and simple method to measure the kinematics of tremor in humans. Further studies are warranted to confirm the validity of each parameter and the diagnostic accuracy in each tremor syndrome.
    03/2014; 4(2). DOI:10.3233/JPD-130311
  • Neurology 02/2014; 82(7):643. · 8.29 Impact Factor
  • Clinical neurology and neurosurgery 01/2014; 116:1-3. DOI:10.1016/j.clineuro.2013.11.012 · 1.13 Impact Factor

Publication Stats

661 Citations
258.27 Total Impact Points


  • 2010–2015
    • King Chulalongkorn Memorial Hospital
      Siayuthia, Bangkok, Thailand
  • 2005–2015
    • Chulalongkorn University
      • Department of Medicine
      Siayuthia, Bangkok, Thailand
    • Tottori University
      • Institute of Neurological Sciences
      TTJ, Tottori, Japan
  • 2003–2011
    • University of California, Los Angeles
      • Department of Neurology
      Los Ángeles, California, United States
  • 2002–2007
    • Harbor-UCLA Medical Center
      Torrance, California, United States