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Fmri dystonia

Martijn P Vlaar, Winfred Mugge, Paul F C Groot, Sarvi Sharifi, Lo J Bour, Frans C T van der Helm, Anne-Fleur van Rootselaar, Alfred C Schouten
Dedicated pairs of isometric wrist flexion tasks, with and without visual feedback of the exerted torque, were designed to target activation of the CBL and BG in healthy subjects during functional magnetic resonance imaging (fMRI). Selective activation of the cerebellum (CBL) and basal ganglia (BG), often implicated in movement disorders such as tremor and dystonia, may help identify pathological changes and expedite diagnosis. A prototyped MR-compatible wrist torque measurement device, free of magnetic and conductive materials, allowed safe execution of tasks during fMRI without causing artifacts...
July 2016: Magnetic Resonance Imaging
Kirsten E Zeuner, Arne Knutzen, Oliver Granert, Simone Sablowsky, Julia Götz, Stephan Wolff, Olav Jansen, Dirk Dressler, Susanne A Schneider, Christine Klein, Günther Deuschl, Thilo van Eimeren, Karsten Witt
Previous receptor binding studies suggest dopamine function is altered in the basal ganglia circuitry in task-specific dystonia, a condition characterized by contraction of agonist and antagonist muscles while performing specific tasks. Dopamine plays a role in reward-based learning. Using fMRI, this study compared 31 right-handed writer's cramp patients to 35 controls in reward-based learning of a probabilistic reversal-learning task. All subjects chose between two stimuli and indicated their response with their left or right index finger...
2016: NeuroImage: Clinical
Wolf-Julian Neumann, Ashwani Jha, Antje Bock, Julius Huebl, Andreas Horn, Gerd-Helge Schneider, Tillmann H Sander, Vladimir Litvak, Andrea A Kühn
Primary dystonia has been associated with an underlying dysfunction of a wide network of brain regions including the motor cortex, basal ganglia, cerebellum, brainstem and spinal cord. Dystonia can be effectively treated by pallidal deep brain stimulation although the mechanism of this effect is not well understood. Here, we sought to characterize cortico-basal ganglia functional connectivity using a frequency-specific measure of connectivity-coherence. We recorded direct local field potentials from the human pallidum simultaneously with whole head magnetoencephalography to characterize functional connectivity in the cortico-pallidal oscillatory network in nine patients with idiopathic dystonia...
July 2015: Brain: a Journal of Neurology
Morvarid Karimi, Joel S Perlmutter
BACKGROUND: Dystonia constitutes a heterogeneous group of movement abnormalities, characterized by sustained or intermittent muscle contractions causing abnormal postures. Overwhelming data suggest involvement of basal ganglia and dopaminergic pathways in dystonia. In this review, we critically evaluate recent neuroimaging studies that investigate dopamine receptors, endogenous dopamine release, morphology of striatum, and structural or functional connectivity in cortico-basal ganglia-thalamo-cortical and related cerebellar circuits in dystonia...
2015: Tremor and Other Hyperkinetic Movements
Catherine F Sinclair, Kristina Simonyan, Mitchell F Brin, Andrew Blitzer
OBJECTIVE: To present the first documented series of patients with negative dystonia (ND) of the palate, including clinical symptoms, functional MRI findings, and management options. STUDY DESIGN: Case series ascertained from clinical research centers that evaluated patients with both hyperkinetic and hypokinetic movement disorders. METHODS: Between July 1983 and March 2013, data was collected on patient demographics, disease characteristics, functional MRI findings, long-term management options, and outcomes...
June 2015: Laryngoscope
R D Bharath, B B Biswal, M V Bhaskar, S Gohel, K Jhunjhunwala, R Panda, L George, A K Gupta, P K Pal
BACKGROUND AND PURPOSE: Writer's cramp (WC) is a focal task-specific dystonia of the hand which is increasingly being accepted as a network disorder. Non-invasive cortical stimulation using repetitive transcranial magnetic stimulation (rTMS) has produced therapeutic benefits in some of these patients. This study aimed to visualize the motor network abnormalities in WC and also its rTMS induced modulations using resting state functional magnetic resonance imaging (rsfMRI). METHODS: Nineteen patients with right-sided WC and 20 matched healthy controls (HCs) were prospectively evaluated...
May 2015: European Journal of Neurology: the Official Journal of the European Federation of Neurological Societies
Victoria Gonzalez, Emmanuelle Le Bars, Laura Cif, Liesjet E H van Dokkum, Isabelle Laffont, Alain Bonafé, Nicolas Menjot de Champfleur, Michel Zanca, Philippe Coubes
Hemidystonia is usually 'secondary' to structural lesions within the cortico-striato-pallido-thalamic or the cerebello-thalamo-cortical loops. Globus pallidus internus Deep Brain Stimulation (GPi DBS) is a validated technique in the treatment of primary dystonia and still under assessment for secondary dystonia. Results of DBS in hemidystonia are limited and heterogeneous. Further knowledge concerning motor network organization after focal brain lesions might contribute to the understanding of this mitigated response to DBS and to the refinement of DBS indications and techniques in secondary dystonia...
June 2015: Brain Imaging and Behavior
Christian Dresel, Yong Li, Verena Wilzeck, Florian Castrop, Claus Zimmer, Bernhard Haslinger
BACKGROUND: Task-specific focal hand dystonia impairs the control of arm muscles during fine motor skills such as writing (writer's cramp (WC)). Functional imaging found abnormal task-related activation of sensorimotor areas in this disorder, but little is known on their functional connectivity (FC). METHODS: Resting-state fMRI and regions of interest (ROI)-voxel cross-correlation analyses were used for systematically analysing the FC between multiple ROIs within the cerebello-basal ganglia-thalamocortical network in 15 patients with right-sided WC and 15 healthy volunteers...
November 2014: Journal of Neurology, Neurosurgery, and Psychiatry
Okka Kimmich, Anna Molloy, Robert Whelan, Laura Williams, David Bradley, Joshua Balsters, Fiona Molloy, Tim Lynch, Daniel G Healy, Cathal Walsh, Seán O'Riordan, Richard B Reilly, Michael Hutchinson
The pathogenesis of adult-onset primary dystonia remains poorly understood. There is variable age-related and gender-related expression of the phenotype, the commonest of which is cervical dystonia. Endophenotypes may provide insight into underlying genetic and pathophysiological mechanisms of dystonia. The temporal discrimination threshold (TDT)-the shortest time interval at which two separate stimuli can be detected as being asynchronous-is abnormal both in patients with cervical dystonia and in their unaffected first-degree relatives...
May 2014: Movement Disorders: Official Journal of the Movement Disorder Society
Jakob Jankowski, Sebastian Paus, Lukas Scheef, Malte Bewersdorff, Hans H Schild, Thomas Klockgether, Henning Boecker
Electrophysiological and behavioral studies in primary dystonia suggest abnormalities during movement preparation, but this crucial phase preceding movement onset has not yet been studied specifically with functional magnetic resonance imaging (fMRI). To identify abnormalities in brain activation during movement preparation, we used event-related fMRI to analyze behaviorally unimpaired sequential finger movements in 18 patients with task-specific focal hand dystonia (FHD) and 18 healthy subjects. Patients and controls executed self-initiated or externally cued prelearnt four-digit sequential movements using either right or left hands...
2013: PloS One
Leighton B N Hinkley, Kensuke Sekihara, Julia P Owen, Kelly P Westlake, Nancy N Byl, Srikantan S Nagarajan
Resting-state imaging designs are powerful in modeling functional networks in movement disorders because they eliminate task performance related confounds. However, the most common metric for quantifying functional connectivity, i.e., bivariate magnitude coherence (Coh), can sometimes be contaminated by spurious correlations in blood-oxygen level dependent (BOLD) signal due to smoothing and seed blur, thereby limiting the identification of true interactions between neighboring neural populations. Here, we apply a novel functional connectivity metric...
2013: Frontiers in Neurology
Stéphane Lehéricy, Marina A J Tijssen, Marie Vidailhet, Ryuji Kaji, Sabine Meunier
This review will consider the knowledge that neuroimaging studies have provided to the understanding of the anatomy of dystonia. Major advances have occurred in the use of neuroimaging for dystonia in the past 2 decades. At present, the most developed imaging approaches include whole-brain or region-specific studies of structural or diffusion changes, functional imaging using fMRI or positron emission tomography (PET), and metabolic imaging using fluorodeoxyglucose PET. These techniques have provided evidence that regions other than the basal ganglia are involved in dystonia...
June 15, 2013: Movement Disorders: Official Journal of the Movement Disorder Society
Cathérine C S Delnooz, Jaco W Pasman, Christian F Beckmann, Bart P C van de Warrenburg
Cervical dystonia is characterized by involuntary, abnormal movements and postures of the head and neck. Current views on its pathophysiology, such as faulty sensorimotor integration and impaired motor planning, are largely based on studies of focal hand dystonia. Using resting state fMRI, we explored whether cervical dystonia patients have altered functional brain connectivity compared to healthy controls, by investigating 10 resting state networks. Scans were repeated immediately before and some weeks after botulinum toxin injections to see whether connectivity abnormalities were restored...
2013: PloS One
Bo Zhou, Jinyu Wang, Yulan Huang, Yousong Yang, Qiyong Gong, Dong Zhou
BACKGROUND: Benign essential blepharospasm (BEB) is a neurologic disorder characterized by an adult-onset focal dystonia that causes involuntary blinking and eyelid spasms. The pathophysiology of BEB patients remains unclear. This study investigated intrinsic low-frequency fluctuation in BEB patients during resting state functional magnetic resonance imaging (fMRI). METHODS: The study included 9 patients with BEB (mean age, 61.7 years; range, 52-66 years), in whom the average duration of symptoms was 2...
September 2013: Journal of Neuro-ophthalmology: the Official Journal of the North American Neuro-Ophthalmology Society
Sandra M A van der Salm, Johan N van der Meer, Aart J Nederveen, Dick J Veltman, Anne-Fleur van Rootselaar, Marina A J Tijssen
BACKGROUND: Myoclonus-dystonia (MD) is a movement disorder characterized by myoclonic jerks, dystonic postures and psychiatric co-morbidity. A mutation in the DYT11 gene underlies half of MD cases. We hypothesize that MD results from a dysfunctional basal ganglia network causing insufficient inhibitory motor control. To test this hypothesis functional MRI (fMRI) was performed using a validated "Go/No go" task, in order to localize blood-oxygen-level dependence (BOLD) effects corresponding to Response Inhibition (RI)...
September 2013: Experimental Neurology
O A Shavlovskaia
Review researches on a problem of muscular dystonia mechanisms formation on an example of a writer's cramp (WC) was presented. WC is a movement disorder, task-specific dystonia, characterised by involuntary excessive muscle contractions producing abnormal postures during selective motor activities that often involve highly skilled, repetitive movements. The precise pathophysiology remains unclear, increasing evidence suggests reduced inhibition at different levels of the sensorimotor system. There has also been a greater understanding of the causes ofdystonic movements, from the study of genetics, neurophysiology (TMS, EMP), and functional imaging (fMRI, PET)...
November 2012: Fiziologiia Cheloveka
S Drapier, M Vérin
Psychogenic Movement Disorders (PMDs) are a subtype of conversion disorder, classified under somatoform disorders in the DSM. Diagnosis and treatment of PMDs are challenging for both neurologists and psychiatrists. Typical clinical characteristics of these disorders are acute onset, fast progression, movement patterns incongruent with organic movement disorders, distractibility, variability and simultaneous occurrence of various abnormal movements and dysfunctions. The diagnosis of PMDs should not be regarded as a diagnosis of exclusion and electrophysiology is not always helpful...
August 2012: Revue Neurologique
Cathérine C S Delnooz, Rick C Helmich, Ivan Toni, Bart P C van de Warrenburg
Writer's cramp is a task-specific form of dystonia with symptoms characterized by abnormal movements and postures of the hand and arm evident only during writing. Its pathophysiology has been related to faulty sensorimotor integration, abnormal sensory processing, and impaired motor planning. Its symptoms might appear when the computational load of writing pushes a tonically altered circuit outside its operational range. Using resting-state fMRI, we tested whether writer's cramp patients have altered intrinsic functional connectivity in the premotor-parietal circuit...
September 15, 2012: Movement Disorders: Official Journal of the Movement Disorder Society
P Stoeter, R Rodriguez-Raecke, C Vilchez, E Perez-Then, H Speckter, J Oviedo, P Roa-Sanchez
BACKGROUND: In a variety of dystonias, functional magnetic resonance imaging has shown deviations of cortical and basal ganglia activations within the motor network, which might cause the movement disturbances. Because these investigations have never been performed in secondary dystonia due to Pantothenate-Kinase Associated Neurodegeneration, we report our results in a small group of such patients from the Dominican Republic. METHODS: Functional magnetic resonance imaging was carried out in 7 patients with a genetically confirmed mutation of the PANK2 gene and a non-affected control group (matched pairs) using an event-related motor activation paradigm (hand movements)...
November 2012: Parkinsonism & related Disorders
Ryan D Moore, Cecile Gallea, Silvina G Horovitz, Mark Hallett
OBJECTIVES: To better understand deficient selective motor control in focal hand dystonia by determining changes in striatal activation and connectivity in patients performing individuated finger control. METHODS: Functional imaging with a 3-Tesla magnetic resonance scanner was performed on 18 patients and 17 controls during non-symptom producing tasks requiring right-handed individuated or coupled finger control. A global linear model and psychophysiologic interaction model compared individuated to coupled tasks for patients and controls separately, and the results were submitted to a group analysis...
July 16, 2012: NeuroImage
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