A Clinical Applicable Smartwatch Application for Measuring Hyperkinetic Movement Disorder Severity

Measuring the severity of hyperkinetic movement disorders like tremor and myoclonus is challenging. Although many accelerometers are available to quantify movements, the vast majority lacks real-time analysis and an interface that makes it possible to real-time adjust therapy like deep brain stimulation (DBS). Here, we developed a smartwatch / smartphone application that is capable of real-time analysing movement disorder severity. Movement analysis was realised by integrating acceleration values, to velocity and subsequently to distance. Measured distances were compared with a validated accelerometer already applied for quantifying movement disorders. Further validation was done by quantitative assessment of simulated movement disorders in 10 healthy volunteers. Finally, the approach was tested in two patients treated with DBS to quantify the effect of different DBS settings on myoclonus and tremor severity, respectively. The distance measured with the application had a 96% accuracy. This was non-inferior (p = 0.76) compared to accelerometers already clinically applied. Furthermore, (simulated) movement disorder severity could be classified correctly in 93% of the cases. Finally, the method was capable of distinguishing effective from non-effective DBS parameters in two patients. In summary, with our approach we realised an instantaneous and reliable estimation of the severity of movement disorders which can assist in real time titrating therapy like DBS.</p

Cruise report hydro acoustic survey for blue whiting (Micromesistius poutassou) with R.V. Tridens, 17 March - 04 April 2008

This is the report of the Dutch part of the international North East Atlantic hydro acoustic survey for blue whiting. The survey is coordinated by ICES and has been executed annually. The purpose of the survey is to estimate the blue whiting stock of the North East Atlantic. The ICES uses this estimation is as a “tuning index” to assess the North East Atlantic blue whiting stock. The applied method was echo integration. By sailing transects over the survey area, the total acoustic cross-section can be calculated by surface area sampled. Trawling identified species composition of localized schools. The length composition of each species was determined. Blue whiting was examined on age and fecundity from which a split up stock structure was mad

Natural course of Myoclonus-Dystonia in adulthood: stable motor signs but increased psychiatry

Myoclonus‐dystonia (M‐D) is a rare hyperkinetic movement disorder characterized by upper body–predominant myoclonus and dystonia.1 A large proportion of cases are caused by autosomal‐dominant inherited mutations in the SGCE gene. In addition to the motor manifestations, psychiatric disorders are frequently reported.2 Several studies have suggested that they may form a primary component of the M‐D phenotype.3, 4 This study represents the first long‐term follow‐up study of both motor and psychiatric symptomatology in adults with M‐D (SGCE mutation), providing further insights into the natural history of M‐D and enabling more prognostic information

Functional Jerky Movements

Functional jerky movements (or functional myoclonus) are commonly seen in patients with functional movement disorder. Positive features both from history and clinical examination are important for the diagnosis. However, due to their heterogeneous and paroxysmal nature a home-made video-recording of the jerky movements can be essential to make the diagnose by a movement disorder specialist. Supportive clinical clues include abrupt symptom onset often triggered by a physical event, whereas entrainment and distractibility are supportive signs during physical examination. Localization of the jerky movements, especially proximal localization, is supportive, and can also be helpful in distinguishing functional jerks from tics and myoclonus, which are the most important differential diagnostic considerations. Additional neurophysiological tests include polymyography and electroencephalography-electromyography (EEG-EMG) co-registration in order to demonstrate a readiness potential (RP). Management includes disease education and specialized physical therapy

The auditory startle response in relation to outcome in functional movement disorders

Background: The auditory startle reflex (ASR) is enlarged in patients with functional movement disorders (FMD). Objectives: To study whether the ASR relates to symptom reduction in FMD patients, who participated in a placebo controlled double blind treatment trial with Botulinum Neurotoxin (BoNT). Methods: Response to treatment in the BoNT study was assessed using the Clinical Global Impression - Improvement scale (CGI-I). The electromyography (EMG) muscle activity of 7 muscles following 110 dB tones was measured in 14 FMD patients before and after one-year treatment and compared to 11 matched controls. The early and a late (behaviorally affected) component of the ASR and the sympathetic skin response (SSR) were assessed. Results: 10 of 14 patients (71.4%) showed symptom improvement, which was believed to be mainly caused by placebo effects. The early total response probability of the ASR at baseline tended to be larger in patients compared to controls (p = 0.08), but normalized at follow-up (p = 0.84). The late total response probability was larger in patients vs. controls at baseline (p < 0.05), a trend that still was present at follow-up (p = 0.08). The SSR was higher in patients vs. controls at baseline (p < 0.01), and normalized at follow-up (p = 0.71). Conclusions: On a group level 71.4% of the patients showed clinical symptom improvement after treatment. The early part of the ASR, most likely reflecting anxiety and hyperarousal, normalized in line with the clinical improvement. Interestingly, the augmented late component of the ASR remained enlarged suggesting persistent altered behavioral processing in functional patients despite motor improvement

Which disease features run in essential tremor families?:A systematic review

Essential tremor is a common and highly heritable movement disorder. It is largely unknown, however, to what extent family members share overlapping symptoms. Such knowledge would be useful, as it may lead to the definition of familial essential tremor phenotypes, which will aid the ongoing search for genotypes. Also, this information can be used by clinicians in patient counselling. Therefore, we conducted a systematic review to provide an overview of the evidence on which essential tremor features run in families, to assess the literature's strengths and weaknesses, and to provide recommendations for future studies. PubMed was searched resulting in 460 titles: sixteen articles ultimately proved fit for inclusion. The results are represented in line with the Axis 1 classification of tremor as published in the latest Consensus Statement. In summary, we found varying levels of positive evidence for familial aggregation of age at onset, disease progression, alcohol responsiveness, parkinsonism and dystonia. Evidence on midline tremor was conflicting. The evidence on familial clustering was negative for cerebellar signs and action tremor asymmetry. Although the level of evidence is modest, it seems that some disease features are indeed familial, while other features are not. We discuss complicating factors, such as state-vs-trait dependency of characteristics, the place of familial dystonia, and the development of diagnostic criteria for essential tremor over time. In the future, comprehensive replication studies are needed, with the addition of several characteristics that have not been investigated so far, as the next step towards discovery of essential tremor phenotypes

Cognition in children and young adults with myoclonus dystonia - A case control study

INTRODUCTION: In adult patients with myoclonus dystonia (MD), cognitive deficits regarding information processing speed and executive functioning have been demonstrated, but it is unclear whether cognition is also affected in young MD patients. The present study investigates cognition in young MD patients and the role of an SGCE mutation. METHODS: In this case control study 20 young MD patients (9 children (5.75-12.58 years) and 11 adolescents/young adults (13.5-25.42 years)) were included and compared to an age-, IQ- and gender-matched healthy control group (n = 40). Within the patient group, we compared patients with (n = 12) and without (n = 8) an SGCE mutation (SGCE+/-). All participants completed neuropsychological tests for memory, attention/processing speed, executive functioning, social cognition and language. RESULTS: Overall, patients performed in the (low) average range, comparable to healthy controls. Only on a semantic fluency test, patients scored significantly lower. SGCE + patients had lower emotion recognition scores (a social cognition test) compared to SGCE-patients. CONCLUSION: We could not demonstrate cognitive deficits as found in adult MD patients in our younger group. Patients performed on the same level as healthy controls, with only a small difference in semantic fluency. We did not find executive deficits that were manifest in adult SGCE + patients, but we did find an association of an SGCE mutation and lower scores on a social cognition test. Similar to executive functioning, social cognition is a prefrontally regulated function, but had not been tested in adult MD. Hence, social cognition may precede executive problems in adulthood, suggesting growing into deficit

Myoclonus-dystonia : distinctive motor and non-motor phenotype from other dystonia syndromes

Background: myoclonus-dystonia (M-D) due to a pathogenic variant of SGCE is an autosomal dominant inherited movement disorder. Apart from motor symptoms, psychiatric disorders are highly prevalent in patients with MD. Previous studies suggest, but never tested directly, that the type of psychiatric disorder differs between dystonia syndromes, probably related to disease specific pathology. Little is known about other non-motor symptoms (NMS) in M.D. Here, we systematically study NMS in M-D in direct comparison to other types of dystonia and healthy controls. Methods: Standardized questionnaires were used to assess type and severity of psychiatric co-morbidity, sleep problems, fatigue and quality of life. Results of M-D patients with a pathogenic variant of SGCE were compared to results of idiopathic cervical dystonia (CD) patients, dopa-responsive dystonia (DRD) patients with a pathogenic variant of GCH1 and controls. Results: We included 164 participants: 41 M-D, 51 CD, 19 DRD patients, 53 controls. Dystonia patients (M-D, CD and DRD) had an increased prevalence of psychiatric disorders compared to controls (56-74% vs. 29%). In M-D we found a significantly increased prevalence of obsessive-compulsive disorder (OCD) and psychosis compared to CD and DRD. All dystonia patients had more sleep problems (49-68% vs. 36%) and fatigue (42-73% vs. 15%) than controls. Compared to other dystonia subtypes, M-D patients reported less excessive daytime sleepiness and fatigue. Conclusion: Psychiatric comorbidity is frequent in all dystonia types, but OCD and psychosis are more common in M-D patients. Further research is necessary to elucidate underlying pathways

Shared demographics and comorbidities in different functional motor disorders

Introduction: Functional motor disorders are often delineated according to the dominant motor symptom. In a large cohort, we aimed to find if there were differences in demographics, mode of onset, pain, fatigue, depression and anxiety and levels of physical functioning, quality of life and social adjustment between patients with different dominant motor symptoms. Methods: Baseline data from the Self-Help and Education on the Internet for Functional Motor Disorders Trial was used. Patients were divided into dominant motor symptom groups based on the diagnosis of the referring neurologist. Data on the above topics were collected by means of an online questionnaire and compared between groups using parametric and nonparametric statistics. Results: In 160 patients a dominant motor symptom could be determined, 31 had tremor, 45 myoclonus, 23 dystonia, 30 paresis, 31 gait disorder. No statistical differences between groups were detected for demographics, mode of onset and severity of pain, fatigue, depression and anxiety. Physical functioning was worse in the gait disorder group (median 20, IQR 25) compared to tremor (50 (55), p = 0.002) and myoclonus (50 (52), p = 0.001). Work and social adjustment was less impaired in the myoclonus group (median 20, IQR 18) compared to gait disorder (median 30, IQR18, p < 0.001) and paresis (28, IQR 10, p = 0.001). Self-report showed large overlap in motor symptoms. Conclusion: No differences were detected between groups of functional motor symptoms, regarding demographics, mode of onset, depression, anxiety, pain and fatigue. The large overlap in symptoms contributes to the hypothesis of shared underlying mechanisms of functional motor disorders