A Novel Video-Based Methodology for Automated Classification of Dystonia and Choreoathetosis in Dyskinetic Cerebral Palsy During a Lower Extremity Task.

BACKGROUND: Movement disorders in children and adolescents with dyskinetic cerebral palsy (CP) are commonly assessed from video recordings, however scoring is time-consuming and expert knowledge is required for an appropriate assessment. OBJECTIVE: To explore a machine learning approach for automated classification of amplitude and duration of distal leg dystonia and choreoathetosis within short video sequences. METHODS: Available videos of a heel-toe tapping task were preprocessed to optimize key point extraction using markerless motion analysis. Postprocessed key point data were passed to a time series classification ensemble algorithm to classify dystonia and choreoathetosis duration and amplitude classes (scores 0, 1, 2, 3, and 4), respectively. As ground truth clinical scoring of dystonia and choreoathetosis by the Dyskinesia Impairment Scale was used. Multiclass performance metrics as well as metrics for summarized scores: absence (score 0) and presence (score 1-4) were determined. RESULTS: Thirty-three participants were included: 29 with dyskinetic CP and 4 typically developing, age 14 years:6 months ± 5 years:15 months. The multiclass accuracy results for dystonia were 77% for duration and 68% for amplitude; for choreoathetosis 30% for duration and 38% for amplitude. The metrics for score 0 versus score 1 to 4 revealed an accuracy of 81% for dystonia duration, 77% for dystonia amplitude, 53% for choreoathetosis duration and amplitude. CONCLUSIONS: This methodology study yielded encouraging results in distinguishing between presence and absence of dystonia, but not for choreoathetosis. A larger dataset is required for models to accurately represent distinct classes/scores. This study presents a novel methodology of automated assessment of movement disorders solely from video data.

The relationship between manual ability, dystonia and choreoathetosis severity and upper limb movement patterns during reaching and grasping in children and young adults with dyskinetic cerebral palsy.

INTRODUCTION: Impaired upper limb movements are a key feature in dyskinetic cerebral palsy (CP). However, information on how specific movement patterns relate to manual ability, performance and underlying movement disorders is lacking. Insight in these associations may contribute to targeted upper limb management in dyskinetic CP. This study aimed to explore associations between deviant upper limb movement patterns and (1) manual ability, (2) severity of dystonia/choreoathetosis, and (3) movement time/trajectory deviation during reaching and grasping. PARTICIPANTS/METHODS: Participants underwent three-dimensional upper limb analysis during reaching forwards (RF), reaching sideways (RS) and reach-and-grasp vertical (RGV) as well as clinical assessment. Canonical correlation and regression analysis with statistical parametric mapping were used to explore associations between clinical/performance parameters and movement patterns (mean and variability). RESULTS: Thirty individuals with dyskinetic CP participated (mean age 16±5 y; 20 girls). Lower manual ability was related to higher variability in wrist flexion/extension during RF and RS early in the reaching cycle (p < 0.05). Higher dystonia severity was associated with higher mean wrist flexion (40-82 % of the reaching cycle; p = 0.004) and higher variability in wrist flexion/extension (31-75 %; p < 0.001) and deviation (2-14 %; p = 0.007/60-73 %; p = 0.006) during RF. Choreoathetosis severity was associated with higher elbow pro/supination variability (12-19 %; p = 0.009) during RGV. Trajectory deviation was associated with wrist and elbow movement variability (p < 0.05). CONCLUSION: Current novel analysis of upper limb movement patterns and respective timings allows to detect joint angles and periods in the movement cycle wherein associations with clinical parameters occur. These associations are not present at each joint level, nor during the full movement cycle. This knowledge should be considered for individualized treatment strategies.

Crossed Choreoathetosis Caused by Unilateral Thalamic Hemorrhage.

In general, involuntary movements after stroke are due to a disturbance in the unilateral cortico-basal ganglia loop and appear contralateral to stroke lesions. Crossed involuntary movements after unilateral stroke are very rare. We observed a case of crossed involuntary movements in the left upper limb and right lower limb after a right thalamic hemorrhage expanded to the right subthalamic nucleus. We considered a possible three-step theory as the basis of crossed choreoathetosis. This case informs our better understanding of the cortico-basal ganglia loop and involuntary movements after stroke.

Improving the objectivity of the current World Para Swimming motor coordination test for swimmers with hypertonia, ataxia and athetosis using measures of movement smoothness, rhythm and accuracy.

The current protocol for classifying Para swimmers with hypertonia, ataxia and athetosis involves a physical assessment where the individual's ability to coordinate their limbs is scored by subjective clinical judgment. The lack of objective measurement renders the current test unsuitable for evidence-based classification. This study evaluated a revised version of the Para swimming assessment for motor coordination, incorporating practical, objective measures of movement smoothness, rhythm error and accuracy. Nineteen Para athletes with hypertonia and 19 non-disabled participants performed 30 s trials of bilateral alternating shoulder flexion-extension at 30 bpm and 120 bpm. Accelerometry was used to quantify movement smoothness; rhythm error and accuracy were obtained from video. Para athletes presented significantly less smooth movement and higher rhythm error than the non-disabled participants (p < 0.05). Random forest algorithm successfully classified 89% of participants with hypertonia during out-of-bag predictions. The most important predictors in classifying participants were movement smoothness at both movement speeds, and rhythm error at 120 bpm. Our results suggest objective measures of movement smoothness and rhythm error included in the current motor coordination test protocols can be used to infer impairment in Para swimmers with hypertonia. Further research is merited to establish the relationship of these measures with swimming performance.

Cluster analysis of impairment measures to inform an evidence-based classification structure in RaceRunning, a new World Para Athletics event for athletes with hypertonia, ataxia or athetosis.

RaceRunning enables athletes with limited or no walking ability to propel themselves independently using a three-wheeled frame that has a saddle, handle bars and a chest plate. For RaceRunning to be included as a para athletics event, an evidence-based classification system is required. This study assessed the impact of trunk control and lower limb impairment measures on RaceRunning performance and evaluated whether cluster analysis of these impairment measures produces a valid classification structure for RaceRunning. The Trunk Control Measurement Scale (TCMS), Selective Control Assessment of the Lower Extremity (SCALE), the Australian Spasticity Assessment Scale (ASAS), and knee extension were recorded for 26 RaceRunning athletes. Thirteen male and 13 female athletes aged 24 (SD = 7) years participated. All impairment measures were significantly correlated with performance (rho = 0.55-0.74). Using ASAS, SCALE, TCMS and knee extension as cluster variables in a two-step cluster analysis resulted in two clusters of athletes. Race speed and the impairment measures were significantly different between the clusters (p < 0.001). The findings of this study provide evidence for the utility of the selected impairment measures in an evidence-based classification system for RaceRunning athletes.

Characterization of the GABRB2-Associated Neurodevelopmental Disorders.

OBJECTIVE: We aimed to characterize the phenotypic spectrum and functional consequences associated with variants in the gene GABRB2, coding for the γ-aminobutyric acid type A (GABAA ) receptor subunit ß2. METHODS: We recruited and systematically evaluated 25 individuals with variants in GABRB2, 17 of whom are newly described and 8 previously reported with additional clinical data. Functional analysis was performed using a Xenopus laevis oocyte model system. RESULTS: Our cohort of 25 individuals from 22 families with variants in GABRB2 demonstrated a range of epilepsy phenotypes from genetic generalized epilepsy to developmental and epileptic encephalopathy. Fifty-eight percent of individuals had pharmacoresistant epilepsy; response to medications targeting the GABAergic pathway was inconsistent. Developmental disability (present in 84%) ranged from mild intellectual disability to severe global disability; movement disorders (present in 44%) included choreoathetosis, dystonia, and ataxia. Disease-associated variants cluster in the extracellular N-terminus and transmembrane domains 1-3, with more severe phenotypes seen in association with variants in transmembrane domains 1 and 2 and the allosteric binding site between transmembrane domains 2 and 3. Functional analysis of 4 variants in transmembrane domains 1 or 2 (p.Ile246Thr, p.Pro252Leu, p.Ile288Ser, p.Val282Ala) revealed strongly reduced amplitudes of GABA-evoked anionic currents. INTERPRETATION: GABRB2-related epilepsy ranges broadly in severity from genetic generalized epilepsy to developmental and epileptic encephalopathies. Developmental disability and movement disorder are key features. The phenotypic spectrum is comparable to other GABAA receptor-encoding genes. Phenotypic severity varies by protein domain. Experimental evidence supports loss of GABAergic inhibition as the mechanism underlying GABRB2-associated neurodevelopmental disorders. ANN NEUROL 2021;89:573-586.

The influence of lower limb impairments on RaceRunning performance in athletes with hypertonia, ataxia or athetosis.

OBJECTIVES: RaceRunning enables athletes with limited or no walking ability to propel themselves independently using a three-wheeled running bike that has a saddle and a chest plate for support but no pedals. For RaceRunning to be included as a Para athletics event, an evidence-based classification system is required. Therefore, the aim of this study was to assess the association between a range of impairment measures and RaceRunning performance. METHODS: The following impairment measures were recorded: lower limb muscle strength assessed using Manual Muscle Testing (MMT), selective voluntary motor control assessed using the Selective Control Assessment of the Lower Extremity (SCALE), spasticity recorded using both the Australian Spasticity Assessment Score (ASAS) and Modified Ashworth Scale (MAS), passive range of motion (ROM) of the lower extremities and the maximum static step length achieved on a stationary bike (MSSL). Associations between impairment measures and 100-meter race speed were assessed using Spearman's correlation coefficients. RESULTS: Sixteen male and fifteen female athletes (27 with cerebral palsy), aged 23 (SD = 7) years, Gross Motor Function Classification System levels ranging from II to V, participated. The MSSL averaged over both legs and the ASAS, MAS, SCALE, and MMT summed over all joints and both legs, significantly correlated with 100 m race performance (rho: 0.40-0.54). Passive knee extension was the only ROM measure that was significantly associated with race speed (rho = 0.48). CONCLUSION: These results suggest that lower limb spasticity, isometric leg strength, selective voluntary motor control and passive knee extension impact performance in RaceRunning athletes. This supports the potential use of these measures in a future evidence-based classification system.

The relationship of dystonia and choreoathetosis with activity, participation and quality of life in children and youth with dyskinetic cerebral palsy.

AIM: To relate dystonia and choreoathetosis with activity, participation and quality of life (QOL) in children and youth with dyskinetic Cerebral Palsy (CP). METHODS: Fifty-four participants with dyskinetic CP (mean age 14y6m, SD 4y2m, range 6-22y) were included. The Dyskinesia Impairment Scale (DIS) was used to evaluate dystonia and choreoathetosis. Activity, participation and quality of life (QOL) were assessed with the Gross Motor Function Measure (GMFM), the Functional Mobility Scale (FMS), the Jebsen-Taylor Hand Function Test (JTT), the ABILHAND-Kids Questionnaire (ABIL-K), the Life Habits Kids (LIFE-H) and the Quality of Life Questionnaire for children with CP (CP-QOL). Spearman's rank correlation coefficient (rs) was used to assess the relationship between the movement disorders and activity, participation and QOL measures. RESULTS: Significant negative correlations were found between dystonia and the activity scales with Spearman's rank correlation coefficient (rs) varying between -0.65 (95% CI = -0.78 to -0.46) and -0.71 (95% CI = -0,82 to -0.55). Correlations were also found with the LIFE-H (rs = -0.43; 95%CI = -0.64 to -0.17) and the CP-QOL (rs = -0.32; 95%CI = -0.56 to -0.03). As far as choreoathetosis is concerned, no or only weak relationships were found with the activity, participation and quality of life scales. INTERPRETATION: This cross-sectional study is the first to examine the relationship of dystonia and choreoathetosis in dyskinetic CP with the level of activity, participation and QOL. The results revealed dystonia has a higher impact on activity, participation and quality of life than choreoathetosis. These findings seem to suggest it is necessary to first focus on dystonia reducing intervention strategies and secondly on choreoathetosis.

Status dystonicus in children: Early recognition and treatment prevent serious complications.

This is a retrospective study of all patients presenting to our paediatric unit with status dystonicus (SD) over a period of five years. Anonymous information was collected and a descriptive analysis is made. There were four episodes of SD in three children between 11 and 15 years of age. All children are known to have severe dyskinetic cerebral palsy and presented with an acute or sub-acute deterioration in their symptoms. Symptoms were triggered by infections in three of the four episodes. Early features included frequent and repetitive generalized muscle spasms, poor swallowing, poor sleep, distress and pain. Patients responded to supportive treatment, rehydration, benzodiazepines, baclofen and l-dopa. Intensive care was not necessary in any of the patients and patients made full recovery within 5-14 days. This report shows the value of early recognition and treatment of SD can be successful in preventing serious complications.

Clinical patterns of dystonia and choreoathetosis in participants with dyskinetic cerebral palsy.

AIM: The aim of the study was to map clinical patterns of dystonia and choreoathetosis and to assess the relation between functional classifications and basal ganglia and thalamus lesions in participants with dyskinetic cerebral palsy (CP). METHODS: In this cross-sectional study, 55 participants with dyskinetic CP (mean age 14y 6mo, SD 4y 1mo; range 6-22y) were assessed with the Dyskinesia Impairment Scale and classified with the Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), and Communication Function Classification System (CFCS). RESULTS: Dystonia and choreoathetosis are simultaneously present. Median levels of dystonia (70.2%) were significantly higher than levels of choreoathetosis (26.7%) and both were significantly higher during activity than at rest (both p<0.01). High correlations were found between dystonia levels and GMFCS level (Spearman's rank correlation coefficient, rS =0.70; 95% confidence interval [CI] 0.53-0.81; p<0.01) and MACS (rS =0.65; 95% CI 0.47-0.81; p<0.01), and fair correlation with CFCS (rs =0.36; 95% CI=0.11-0.57; p<0.05). No significant correlation was found between choreoathetosis levels and motor classifications. Finally, higher choreoathetosis levels were found in participants with pure thalamus and basal ganglia lesions (p=0.03) than mixed lesions, but not for dystonia (p=0.41). INTERPRETATION: Dystonia and choreoathetosis increase during activity. However, dystonia predominates and seems to have a larger impact on functional abilities. Our findings further suggest that choreoathetosis seems to be more linked to pure thalamus and basal ganglia lesions than dystonia.

Improving Target Acquisition for Computer Users With Athetosis.

Prior work has highlighted the challenges faced by people with athetosis when trying to acquire on-screen targets using a mouse or trackball. The difficulty of positioning the mouse cursor within a confined area has been identified as a challenging task. We have developed a target acquisition assistance algorithm that features transition assistance via directional gain variation based on target prediction, settling assistance via gain reduction in the vicinity of a predicted target, and expansion of the predicted target as the cursor approaches it. We evaluated the algorithm on improving target acquisition efficiency among seven participants with athetoid cerebral palsy. Our results showed that the algorithm significantly reduced the overall movement time by about 20%. Considering the target acquisition occurs countless times in the course of regular computer use, the accumulative effect of such improvements can be significant for improving the efficiency of computer interaction among people with athetosis.

[Familial and non-familial benign infantile seizures: A homogeneous entity?]. / Convulsions infantiles bénignes familiales et non familiales : une entité homogène ?

Among the epileptic syndromes occurring during infancy, which are mostly non-idiopathic and associated with a poor prognosis, benign infantile convulsions are characterized by a favourable evolution. This work aims to analyse and compare the clinical, EEG and outcome characteristics of familial benign infantile convulsions (FBIC) and non-familial benign infantile convulsions (NFBIC). This is a retrospective study, conducted between 1988 and 2008, in 40 infants who presented benign infantile seizures during the two first years of life. All of them had no personal history, normal psychomotor development, normal neurological examinations, no abnormalities on biological and radiological investigations and a favourable outcome. In 14 cases, there was a familial history of familial benign infantile convulsions. However, among the 26 cases with non-familial benign infantile convulsions, 11 children had a familial history of other epileptic syndrome. That may suggest a genetic familial susceptibility. In the two groups, the clinical features and the electroencephalography were similar. The seizures had short duration and occurred most often in clusters. Twenty-nine children had secondarily generalized partial seizures and 11 infants had generalized seizures but a focal onset cannot be excluded. The antiepileptic drugs allowed rapid resolution of seizures. One child necessitated a prolonged antiepileptic treatment. In the other cases, seizures cured in the first year without recurrence of seizures after treatment discontinuation. The evolution was characterised in five children by a later occurrence of dystonia. This subgroup was described as infantile convulsion and choreoathetosis syndrome (ICCA). Benign infantile convulsions are probably an underestimated epileptic syndrome. The diagnosis is relatively easy in the familial forms with dominant autosomal transmission. In contrast, in sporadic forms, the diagnosis can be confirmed only by the evolution. The good prognosis must be tempered by the subsequent onset of dystonia consisted in the ICCA syndrome and justifies a prolonged follow-up.

Algorithms for target prediction for computer users with athetosis.

Athetosis is a movement disorder that afflicts numerous persons with cerebral palsy, resulting in significant problems in their control of computer interfaces. As a step toward increasing the efficiency of icon selection by computer users with athetosis, we have implemented three techniques to reduce the time of target acquisition: transition assistance via directional gain variation based on target prediction during initial movement toward the target, settling assistance via gain reduction when in the vicinity of a predicted target, and expansion of the predicted target as the cursor approaches it. The paper describes each method, and presents results from evaluation of each method using a closed-loop model of a human subject with athetosis, trained using recorded data, at three different severity levels.

Age, dose, and time-dependency of plasma and tissue distribution of deltamethrin in immature rats.

The major objective of this project was to characterize the systemic disposition of the pyrethroid, deltamethrin (DLT), in immature rats, with emphasis on the age dependence of target organ (brain) dosimetry. Postnatal day (PND) 10, 21, and 40 male Sprague-Dawley rats received 0.4, 2, or 10 mg DLT/kg by gavage in glycerol formal. Serial plasma, brain, fat, liver, and skeletal muscle samples were collected for up to 510 h and analyzed for DLT and/or 3-phenoxybenzoic acid (PBA) content by high-performance liquid chromatography. Toxicokinetic data from previous experiments of the same design with young adult (PND 90) rats (Kim, K.-B., Anand, S. S., Kim, H. J., White, C. A., and Bruckner, J. V. [2008]. Toxicokinetics and tissue distribution of deltamethrin in adult Sprague-Dawley rats. Toxicol. Sci. 101, 197-205) were used to compare to immature rat data. Plasma and tissue DLT levels were inversely related to age. Preweanlings and weanlings showed markedly elevated brain concentrations and pronounced salivation, tremors, choreoathetosis, and eventual fatalities. Plasma DLT levels did not reliably reflect brain levels over time. Plasma:brain ratios were time and dose dependent, but apparently not age dependent. Brain levels were better correlated with the magnitude of salivation and tremors than plasma levels. Hepatic intrinsic clearance of DLT progressively increased during maturation, as did the hepatic extraction ratio. Thus, limited capacity to metabolically inactivate DLT appeared primarily responsible for the inordinately high target organ doses and acute neurotoxicity in pups and weanling rats. Hepatic blood flow was not rate limiting in any age group. Limited DLT hydrolysis was manifest in vivo in the pups by relatively low plasma PBA levels. Elevated exposure of the immature brain to a pyrethroid may prove to be of consequence for long-term, as well as short-term neurotoxicity.

Hyperkinetic movement disorder in a child treated by globus pallidus stimulation.

We report herein the case of a 9-year-old girl with life-threatening hyperkinetic involuntary movement of unknown etiology. Medical treatment was ineffective for her stereotypy and choreoathetotic/ballistic movements, but bilateral stimulation of the globus pallidus immediately alleviated these symptoms. Pallidal deep-brain stimulation may be considered the therapy of choice for children with intractable hyperkinetic movement disorders.