Post-stroke dyskinesias

Which cutoff value of the Montreal Cognitive Assessment should be used for post-stroke cognitive impairment? A systematic review and meta-analysis on diagnostic test accuracy

BACKGROUND

Post-stroke cognitive impairment (PSCI) is one of the serious complications of stroke. The Montreal Cognitive Assessment (MoCA), as a brief cognitive impairment screening tool, is widely used in stroke survivors. However, some studies have suggested that the use of the universal cutoff value of 26 may be inappropriate for detecting cognitive impairments in stroke settings.

AIM

We conducted this study to identify the optimal cutoff value of the MoCA in screening for PSCI.

METHODS

PubMed, CINAHL, Embase, the Cochrane Library, and Web of Science were searched for eligible studies until March 23, 2023. All studies were screened by two independent researchers. The quality of each article was evaluated by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate mixed-effects model was used to pool sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the summary receiver operating characteristic curve.

RESULTS

Twenty-four studies with a total of 4231 patients were included in this review. Despite the lack of evidence of publication bias, a high degree of heterogeneity was observed. A meta-analysis revealed that a cutoff value of 21/22 yielded the best diagnostic accuracy. The optimal cutoff varied in different regions, stroke types, and stroke phases as well.

CONCLUSION

The optimal cutoff of MoCA was 21/22 for stroke populations rather than the initially recommended cutoff of 26. A revised (lower) cutoff should be considered for stroke survivors.

A Kinematic Data-Driven Approach to Differentiate Involuntary Choreic Movements in Individuals With Neurological Conditions

OBJECTIVE

The ability to differentiate similar choreic involuntary movements could lay the groundwork for the development of a minimally-invasive screening tool for their etiology and provide in-depth understandings of pathophysiology. As a first step, we investigate kinematic differences between Huntington's disease (HD) chorea and Parkinson's disease (PD) choreic levodopa-induced dyskinesia (LID), which have distinct pathological causes yet share a great kinematic resemblance.

METHODS

Twenty subjects with HD and ten subjects with PD stood with both upper limbs in front of them for approximately 60 seconds. The three-dimensional velocity time-series of involuntary movements of both hands were segmented into one-dimensional sub-movements abutted by velocity zero-crossings. A combination of unsupervised and supervised machine learning algorithms was employed to automatically select data features extracted from sub-movements and distinguish the two types of involuntary choreic movements.

RESULTS

The trained model was able to accurately classify chorea vs. LID with an Area Under the Receiver Operating Characteristic Curve of 99.5%. A set of important features contributing to the construction of the classification model were identified and investigated.

CONCLUSION

The trained model may serve as a tool for the automatic identification of different types of involuntary choreic movements, enabling continuous monitoring and personalized treatment for patients in various clinical settings.

SIGNIFICANCE

The results provide insights into kinematic characteristics of HD chorea and PD LID, which is the first step towards an improved general understanding of involuntary choreic movements.

Dystonia as a Presenting Feature of Acute Ischemic Stroke: A Case Report and Literature Review

Hypokinetic and hyperkinetic movement disorders can occur post-stroke. Of these, dystonia is known to occur in the chronic stage of stroke. Rarely, acute dystonia can present as a symptom of acute ischemic stroke or develop during hospitalization for ischemic stroke. In this article, we present a case of acute focal dystonia as a presenting symptom of acute ischemic stroke, review the literature to summarize previous reports, and provide more insight into the pathophysiologic mechanisms related to this presentation.

Post-stroke Movement Disorders: Clinical Spectrum, Pathogenesis, and Management

Involuntary movements develop after 1-4% of strokes and they have been reported in patients with ischemic and hemorrhagic strokes affecting the basal ganglia, thalamus, and/or their connections. Hemichorea-hemiballism is the most common movement disorder following a stroke in adults while dystonia is most common in children. Tremor, myoclonus, asterixis, stereotypies, and vascular parkinsonism are other movement disorders seen following stroke. Some of them occur immediately after acute stroke, some can develop later, and others may have delayed onset progressive course. Proposed pathophysiological mechanisms include neuronal plasticity, functional diaschisis, and age-related differences in brain metabolism. There are no guidelines regarding the management of post-stroke movement disorders, mainly because of their heterogeneity.

Clinical features of hemichoreahemiballism: A stroke-related movement disorder

We examined pathogenesis and clinical features of three hemichorea-hemiballism (HCHB) cases. We studied their age, magnetic resonance imaging results, vascular risk factors, management, and outcomes. One man and two women (aged 74-86 years) demonstrated acute onset of HCHB, lasting for at least several months. Patients had one or more vascular risk factors, including hypertension and diabetes. All patients presented subacute or old infarction in the basal ganglia with contralateral symptoms. We administered clonazepam (0.5-1 mg/day), haloperidol (0.375-0.75 mg/day), or both as necessary and observed symptom-control. Vascular lesions in the basal ganglia were a contributing factor. Symptoms were controlled using pharmacotherapy with gamma-aminobutyric acid-agonist (clonazepam) or anti-dopaminergic (haloperidol) medication.

Combined machine learning and functional magnetic resonance imaging allows individualized prediction of high-altitude induced psychomotor impairment: The role of neural functionality in putamen and pallidum

Hypoxia exposure during high-altitude expedition cause psychomotor impairment. Neuroimaging studies indicated that the impairment may be significantly associated with neuron loss and decreased regional homogeneity (ReHo) in several brain regions, suggesting the neural functionality in these regions may be utilized to predict psychomotor impairment under exposure. In this study, 69 subjects come from Shaanxi-Tibet immigrant cohort. Reaction time (RT) tasks were performed to measure the subject's psychomotor function before and after 2-year high-altitude exposure. For each individual, the RT differences between pre-exposure and post-exposure were calculated, which were referred to as "targets" in model establishment. Rs-fMRI data were acquired at the same time with RT tasks. For each individual, the map of ReHo alteration was generated, from which the patterns would be recognized. A pattern recognition procedure was utilized to train and test the predictive models. Two different cross-validation strategies were utilized to evaluate the model performance: leave-one-out cross-validation and four-fold cross-validation. For the models displaying significant R² and MSE, weight maps were built. As a result, the predictive models were able to decode the changes of simple and recognition reaction time from the alterations of brain activation under the exposure. The regions with highest contributions to the predictions were bilateral putamen and bilateral pallidum, suggesting that predictions were mainly based on the patterns concentrated in these regions. This study was a proof of concept study designed to examine whether individual-level psychomotor impairment under high-altitude exposure could be predicted by a combination of pattern recognition approach and neuroimaging data.

Autoimmune Movement Disorders in Children

Over the last decade, there have been significant advances in the identification, characterization, and treatment of autoimmune neurologic disorders in children. Many of these diseases include a typical movement disorder that can be a powerful aid to diagnosis. Frequently, movement disorders in autoimmune conditions are the sole or among a few presenting symptoms, allowing for earlier diagnosis of an underlying malignancy or systemic autoimmune disease. Given that early detection and treatment with immunotherapy may confer improved outcomes, recognizing these patterns of abnormal movements is essential for child neurologists. The purpose of this review is to summarize the clinical characteristics, diagnosis, and treatment of movement disorders that occur in pediatric autoimmune disorders.

Punding following posterior cerebral artery infarction: a case report and literature review

INTRODUCTION

Punding is a complex stereotyped behavior, characterized by excessiveness, non-goal orientation, and repetitiveness. It is mostly associated with Parkinson's disease, and very few cases in non-Parkinson's disease have been reported. We report a case of punding associated with supratentorial ischemic stroke.

CASE PRESENTATION

We present a 70-year-old man with left posterior cerebral artery infarction with quetiapine-induced punding manifesting as repetitive unidirectional body turning. Remission of punding behavior ensued after cessation of quetiapine and administration of clonazepam.

CONCLUSION

This case describes the clinical course of quetiapine-induced punding in a patient with left posterior cerebral artery infarction. It suggests clonazepam may serve as a treatment option for poststroke punding.