Publications by authors named "Michel Rijntjes"

Delayed therapy escape (DTE) is frequent after thalamic deep brain stimulation for essential tremor, leading to reduced quality of life, often with ataxic symptoms, and early recognition is challenging. Our goal was to examine whether a low-frequency rebound tremor of the left hand after switching off stimulation is useful as a diagnostic marker for DTE. In this cross-sectional study with additional retrospective analysis, we examined 31 patients with bilateral thalamic DBS ≥ 12 months for essential tremor, using quantitative assessments including video-based motion capture, Fahn-Tolosa-Marin Tremor Rating Scale (FTMTRS), and scale for the assessment and rating of ataxia (SARA).

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The arcuate fasciculus may be subdivided into a tract directly connecting frontal and temporal lobes and a pair of indirect subtracts in which the fronto-temporal connection is mediated by connections to the inferior parietal lobe. This tripartition has been advanced as an improvement over the centuries-old consensus that the lateral dorsal association fibers form a continuous system with no discernible discrete parts. Moreover, it has been used as the anatomical basis for functional hypotheses regarding linguistic abilities.

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  • Patients with Lewy body diseases, including Parkinson's disease and related dementias, have a higher risk of dementia, which significantly affects survival rates.
  • A study analyzed cerebral glucose metabolism using PET scans and found that lower metabolism in specific brain regions predicted shorter survival, with significant differences in median survival based on the severity of metabolic decline.
  • The findings suggest that PET scans could be a valuable tool for earlier predictions of survival in these patients, potentially aiding in treatment decisions, such as whether to consider deep brain stimulation.
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  • The study investigates how the microstructural integrity of specific brain areas (substantia nigra, subthalamic nucleus, putamen) relates to the effectiveness of deep brain stimulation (DBS) in patients with Parkinson's disease.
  • It involved 23 Parkinson's patients who underwent advanced MRI to assess brain microstructure before receiving STN-DBS and measured their motor improvements afterward.
  • Results indicated a trend where poorer response to DBS correlated with increased free interstitial fluid in the substantia nigra and subthalamic nucleus, suggesting these areas may serve as biomarkers for predicting treatment outcomes, but further research is needed for definitive conclusions.
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  • - Device aided therapies (DAT) like LCIG, LECIG, CSAI, and DBS are used for Parkinson's disease when medications alone aren't enough, each with unique effectiveness, risks, and suitability.
  • - These therapies should be evaluated individually as patients experience symptoms differently over time; one-size-fits-all approaches may not be effective.
  • - The study emphasizes the need for ongoing assessments of patients to tailor DAT to their specific needs, enhancing both motor and non-motor symptom management.
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Background: Thalamic deep brain stimulation (DBS) is an efficacious treatment for drug-resistant essential tremor (ET) and the dentato-rubro-thalamic tract (DRT) constitutes an important target structure. However, up to 40% of patients habituate and lose treatment efficacy over time, frequently accompanied by a stimulation-induced cerebellar syndrome. The phenomenon termed delayed therapy escape (DTE) is insufficiently understood.

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  • In Parkinson's disease treatment, different methods like Levodopa/Carbidopa Intestinal Gel (LCIG), Levodopa/Carbidopa/Entacapone Intestinal Gel (LECIG), and deep brain stimulation (DBS) are used, each with distinct effectiveness and side effects.
  • The authors argue that patients don't all reach the same stage for these treatments at the same time, suggesting that individual disease progression should guide treatment initiation rather than a fixed timeline.
  • The review emphasizes personalized treatment approaches that focus on improving quality of life and engagement rather than adhering to a standardized treatment schedule.
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  • The study aimed to assess different MRI techniques for distinguishing between various neurodegenerative Parkinson syndromes (NPS) like Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy.
  • Researchers analyzed macrostructural and microstructural MRI data from patients with NPS and healthy controls, using machine learning to compare their diagnostic performances.
  • The results indicated that combining macrostructural and microstructural MRI provided the best classification accuracy, highlighting the added value of advanced imaging techniques over traditional methods.
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  • Multiple system atrophy (MSA) presents in two main forms: MSA-P with Parkinson's symptoms and MSA-C with cerebellar issues, both causing impaired dexterity.
  • The study compared brain imaging and dexterity performance between MSA patients and healthy controls to understand how different degeneration patterns contribute to motor difficulties.
  • Results show cerebellar degeneration affects dexterity in both MSA types, indicating it may be a useful biomarker for tracking disease progression, while nigrostriatal degeneration showed no significant impact on dexterity.
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  • Advanced therapies (ATs) like deep brain stimulation and pump therapies are used for advanced Parkinson's disease but may lose effectiveness or cause side effects, necessitating changes or combinations of treatments.
  • A nationwide study in Germany analyzed data from 22 centers to assess the effects and reasons for modifications in these ATs, using retrospective questionnaires to gather relevant clinical information since 2005.
  • Results showed that 148 modifications across 116 patients led to significant improvements in symptom control and reduced side effects, with the main reasons for changes being inadequate symptom management and side effects from previous treatments.
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Background: Cognitive deficits considerably contribute to the patient's burden in Parkinson's disease (PD). While cognitive decline is linked to neuronal dysfunction, the additional role of white matter lesions (WML) is discussed controversially.

Objective: To investigate the influence of WML, in comparison to neuronal dysfunction, on cognitive deficits in PD.

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The left hemisphere tool-use network consists of the dorso-dorsal, ventro-dorsal, and ventral streams, each with distinct computational abilities. In the dual-loop model, the ventral pathway through the extreme capsule is associated with conceptual understanding. We performed a learning experiment with fMRI to investigate how these streams interact when confronted with novel tools.

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Background: Telemedicine has rapidly emerged as an important tool in emergency neurology. In particular, reliable biomarkers of large vessel occlusions (LVOs) are critically necessary in order to identify the need for in-hospital mechanical thrombectomy (MT). Based on pathophysiological factors, we propose that the presence of head and/or gaze deviation alone signifies cortical hypoperfusion and is therefore a highly sensitive marker for the presence of LVO.

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Objectives: The precise segmentation of atrophic structures remains challenging in neurodegenerative diseases. We determined the performance of a Deep Neural Patchwork (DNP) in comparison to established segmentation algorithms regarding the ability to delineate the putamen in multiple system atrophy (MSA), Parkinson's disease (PD), and healthy controls.

Methods: We retrospectively included patients with MSA and PD as well as healthy controls.

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This scientific commentary refers to ‘Joint impact on attention, alertness and inhibition of lesions at a frontal white matter crossroad’ by Kaufmann . (https://doi.org/10.

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Objectives: The integrity of cortical motor networks and their descending effector pathway (the corticospinal tract [CST]) is a major determinant motor recovery after stroke. However, this view neglects the importance of ascending tracts and their modulatory effects on cortical physiology. Here, we explore the role of such a tract that connects dopaminergic ventral tegmental midbrain nuclei to the motor cortex (the VTMC tract) for post-stroke recovery.

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The extent to which the degeneration of the substantia nigra (SN) and putamen each contribute to motor impairment in Parkinson's disease (PD) is unclear, as they are usually investigated using different imaging modalities. To examine the pathophysiological significance of the SN and putamen in both motor impairment and the levodopa response in PD using diffusion microstructure imaging (DMI). In this monocentric retrospective cross-sectional study, DMI parameters from 108 patients with PD and 35 healthy controls (HC) were analyzed using a voxel- and region-based approach.

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Parkinson's disease (PD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP) are characterized by nigrostriatal degeneration. We used [F]FDG PET to assess glucose metabolism of the substantia nigra (SN) in patients with these diseases and evaluated its ability to discriminate neurodegenerative parkinsonian syndromes (NP) from controls. We retrospectively evaluated [F]FDG PET scans of 171 patients with NP (n = 115 PD, n = 35 MSA, n = 21 PSP) and 48 controls (13 healthy controls [HC] and 35 control patients).

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Intelligible communication with others as well as covert conscious thought requires us to combine a representation of the external world with inner abstract concepts. Interaction with the external world through sensory perception and motor execution is arranged as sequences in time and space, whereas abstract thought and invariant categories are independent of the moment. Using advanced MRI-based fibre tracking on high resolution data from 183 participants in the Human Connectome Project, we identified two large supramodal systems comprising specific cortical regions and their connecting fibre tracts; a dorsal one for processing of sequences in time and space, and a ventral one for concepts and categories.

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Background: Delayed therapy escape after thalamic deep brain stimulation (DBS) for essential tremor is a serious yet frequent condition. It is often difficult to detect this process at onset due to its gradual evolution.

Objective: Here we aim to identify clinical and neuroimaging hallmarks of delayed therapy escape.

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The anatomical relationship between speech apraxia (SA) and oral apraxia (OA) is still unclear. To shed light on this matter we studied 137 patients with acute ischaemic left-hemisphere stroke and performed support vector regression-based, multivariate lesion-symptom mapping. Thirty-three patients presented with either SA or OA.

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