Standardized handwriting to assess bradykinesia, micrographia and tremor in Parkinson's disease (original) (raw)
Related papers
Journal of Neurology, 2012
Handwriting examinations are commonly performed in the analysis of tremor and Parkinson's disease (PD). We analyzed the accuracy of subjective and objective assessment of handwriting samples for distinguishing 27 PD cases, 22 with tremulous PD, and five with akinetic-rigid PD, from 39 movement-disorder patients with normal presynaptic dopamine imaging (subjects without evidence of dopamine deficiency or SWEDDs; 31 with dystonic tremor (DT), six indeterminate tremor syndrome, one essential tremor, one vascular parkinsonism). All handwriting analysis was performed blind to clinical details. Subjective classification was made as: (1) micrographia, (2) normal, or (3) macrographia. In addition, a range of objective metrices were measured on standardized handwriting specimens. Subjective assessments found micrographia more frequently in PD than SWEDDs (p = 0.0352) and in akinetic-rigid than tremulous PD (p = 0.0259). Macrographia was predominantly seen in patients with dystonic tremor and not other diagnoses (p = 0.007). Micrographia had a mean sensitivity of 55 % and specificity of 84 % for distinguishing PD from SWEDDs and mean sensitivity of 90 % and specificity of 55 % for distinguishing akinetic-rigid PD from tremulous PD. Macrographia had a sensitivity of 26 % and specificity of 96 % for distinguishing DT from all other diagnoses. The best of the objective metrices increased sensitivity for the distinction of SWEDDs from PD with a reduction in specificity. We conclude that micrographia is more indicative of PD than SWEDDs and more characteristic of akinetic-rigid than tremulous PD. In addition, macrographia strongly suggests a diagnosis of dystonic tremor.
Validity and reliability of a new tool to evaluate handwriting difficulties in Parkinson’s disease
PLOS ONE, 2017
Background Handwriting in Parkinson's disease (PD) features specific abnormalities which are difficult to assess in clinical practice since no specific tool for evaluation of spontaneous movement is currently available. Objective This study aims to validate the 'Systematic Screening of Handwriting Difficulties' (SOS-test) in patients with PD. Methods Handwriting performance of 87 patients and 26 healthy age-matched controls was examined using the SOS-test. Sixty-seven patients were tested a second time within a period of one month. Participants were asked to copy as much as possible of a text within 5 minutes with the instruction to write as neatly and quickly as in daily life. Writing speed (letters in 5 minutes), size (mm) and quality of handwriting were compared. Correlation analysis was performed between SOS outcomes and other fine motor skill measurements and disease characteristics. Intrarater, interrater and test-retest reliability were assessed using the intraclass correlation coefficient (ICC) and Spearman correlation coefficient. Results Patients with PD had a smaller (p = 0.043) and slower (p<0.001) handwriting and showed worse writing quality (p = 0.031) compared to controls. The outcomes of the SOS-test significantly correlated with fine motor skill performance and disease duration and severity. Furthermore, the test showed excellent intrarater, interrater and test-retest reliability (ICC > 0.769 for both groups).
Distinctive Handwriting Signs in Early Parkinson’s Disease
Applied Sciences
Background: The analysis of handwriting movements to quantify motor and cognitive impairments in neurodegenerative diseases is increasingly attracting interest. Non-invasive and quick-to-administer tools using handwriting movement analysis can be used in early screening of Parkinson’s disease (PD) and maybe in the diagnosis of other neurodegenerative disease. Theaim of this work is to identify the distinctive signs characterizing handwriting in the early stage of PD, in order to provide a diagnostic tool for the early detection of the disease. Compared to previous studies, here, we analyzed handwriting movements of patients on which the disease affects the contralateral side with respect to the one used for writing. Methods: We collected and analyzed a set of handwriting samples by PD patients and healthy subjects. Participants were asked to follow a novel protocol, containing handwriting patterns of various levels of complexity, using both familiar and unfamiliar movements. Results...
Sensorimotor Impairment in the Elderly, 1993
It has often becn suggested 0rat handwriting featurcs may allow carly diagnosis of Parkinson's discase. Instcad of searching for carly nradlcru by longitudinal studics onc may idcntify appropriate early nrarkcrs by dcrnonslrating that ilrc nrarlicrs dcpcnd littlc upon the nonnal deterioration with age whilc nrarkedly changing by thc prcscnce of thc disease. I{owever, studics of the dcvelopurcnt of handwriting skills in young adults and elderly in connection to patients rvitlr agc-rclrtcd scnsorimotor inrpairment arc sparsc. In lhe expe rinrcnt, subjects rcpeatcdly pcrfomred a sprccific handwriting pattenr undcr various conditions and instructions: writing larger, faster, or slower than nomral. or writing with reduced tactile and/or visual fecdback. The hurdrvriting pattems werc rcc<lrded in tinrc iurd space using a digitizer, autonratically scgmentcd into handwriting strokcs, and analyz.ed in temrs of venical size, pcak accelcration (i.e., force amplitudc), and duration. lvlcans arxl signal-to-noisc ratios (SNRs) wcrc cstinlatcd for cach subjcct and condition. Thc SNR rvas used to quantify in a unit-frce scale thc accuracics of sizc, forcc, and tirning contrul. It appears that in all conditions (a) tlrc accuracy of stroke sizes, (b) tlrc accuracy of pcak accelerations (i.e., force arnplitudcs) and (c) thc mean strokc duration wcrc strongly affccted by the prcscnce o[ Parliinson's discase and not b1, age. Thercforc. thcse thrcc handwriting fcaturcs nray bc considcrcd appropriatc early marlies for Parkinson's discasc.
Handwriting with different effectors in individuals with Parkinson's disease
Parkinsonism & Related Disorders, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
A Kinematic Study of Progressive Micrographia in Parkinson's Disease
Frontiers in Neurology
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.
From micrographia to Parkinson's disease dysgraphia
Movement Disorders, 2014
A B S T R AC T : Micrographia, an abnormal reduction in writing size, is a specific behavioral deficit associated with Parkinson's disease (PD). In recent years, the availability of graphic tablets has made it possible to study micrographia in unprecedented detail. Consequently, a growing number of studies show that PD patients also exhibit impaired handwriting kinematics. Is micrographia still the most characteristic feature of PD-related handwriting deficits? To answer this question, we identified studies that investigated handwriting in PD, either with conventional pencil-and-paper measures or with graphic tablets, and we reported their findings on key spatiotemporal and kinematic variables. We found that kinematic variables (velocity, fluency) differentiate better between control participants and PD patients, and between off-and on-treatment PD patients, than the traditional measure of static writing size. Although reduced writing size is an important feature of PD handwriting, the deficit is not restricted to micrographia stricto sensu. Therefore, we propose the term PD dysgraphia, which encompasses all deficits characteristic of Parkinsonian handwriting. We conclude that the computerized analysis of handwriting movements is a simple and useful tool that can contribute to both diagnosis and follow-up of PD. V C 2014 International Parkinson and Movement Disorder Society
Contribution of different handwriting modalities to differential diagnosis of Parkinson's Disease
2015 IEEE International Symposium on Medical Measurements and Applications (MeMeA) Proceedings, 2015
In this paper, we evaluate the contribution of different handwriting modalities to the diagnosis of Parkinson's disease. We analyse on-surface movement, in-air movement and pressure exerted on the tablet surface. Especially in-air movement and pressure-based features have been rarely taken into account in previous studies. We show that pressure and in-air movement also possess information that is relevant for the diagnosis of Parkinson's Disease (PD) from handwriting. In addition to conventional kinematic and spatio-temporal features we present group of novel features based on entropy and empirical mode decomposition of the handwriting signal. The presented results indicate that handwriting can be used as biomarker for PD providing classification performance around 89% area under the ROC curve (AUC) for PD classification.
The influence of mental and motor load on handwriting movements in Parkinsonian patients
Acta Psychologica, 1998
This experiment tested the hypothesis that ParkinsonÕs disease (PD) patients are more vulnerable to a moderate level of secondary task load than elderly or young controls due to heightened variability in the motor system. PD patients, elderly, and young adults performed a handwriting task with dierent secondary tasks. The secondary task imposed motor load (i.e., speech) and/or a mental load (i.e., ignoring, repeating, or subtracting). The ®ndings showed that, in contrast to young and elderly controls, PD patients tended to increase MT, accumulated pause time, and normalized jerk when the secondary task consisted primarily of motor load. Furthermore, it was shown that PD patients did not reduce writing sizes as result of a high level of mental load which ®nding suggests that writing in an automated fashion does not result in micrographia. The results are discussed in relation to strategies imposed to contend with reduced signal-to-noise levels in the motor system. Ó 1998 Elsevier Science B.V. All rights reserved. 0001-6918/98/$ ± see front matter Ó 1998 Elsevier Science B.V. All rights reserved. PII: S 0 0 0 1 -6 9 1 8 ( 9 8 ) 0 0 0 3 2 -8
Handwriting Rehabilitation in Parkinson Disease: A Pilot Study
Annals of rehabilitation medicine, 2015
To assess the utility of handwriting rehabilitation (HR) in Parkinson disease (PD) patients who experienced difficulties with handwriting and signing. Sixty PD patients were prospectively studied with graphological evaluations. Thirty PD patients were assigned to HR for 9 weeks. At the end of this training, all patients were evaluated again and results of basal vs. final evaluations were compared. At final evaluation, the group assigned to HR showed significantly larger amplitude of the first 'e' in the phrase, larger signature surface area, and superior margin. A trend of increase in letter size was also observed. Handwriting with progressively decreasing size of letters and ascending direction with respect to the horizontal were prominent findings in both groups of patients and they did not change after HR. Rehabilitation programs for handwriting problems in PD patients are likely to be helpful. Larger randomized studies are needed to confirm these results.