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Journal of Neurology Oct 2023With the development of noninvasive brain stimulation (NIBS) techniques, many researchers have turned their attention to NIBS as a promising treatment for cerebellar... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
With the development of noninvasive brain stimulation (NIBS) techniques, many researchers have turned their attention to NIBS as a promising treatment for cerebellar ataxia. Therefore, we conducted a systematic review and meta-analysis to investigate the efficacy and safety of NIBS in treating patients with cerebellar ataxia.
METHODS
Databases, including PubMed, Embase, Web of Science, Medline, and Cochrane Library, were retrieved for relevant randomized controlled trials (RCTs). Two researchers conducted literature screening, data extraction, literature quality assessment, and heterogeneity analysis between RCTs. According to the magnitude of heterogeneity I, an appropriate data analysis model was selected for meta-analysis.
RESULTS
A total of 14 RCTs including 406 patients with cerebellar ataxia met the inclusion criteria. The included RCTs had an overall low-risk bias and an intermediate level of evidence recommendation for key outcome indicators, such as the scale for the assessment and rating of ataxia (SARA) and international cooperative ataxia rating scale (ICARS). The results of meta-analysis showed that cerebellar NIBS, including transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS), was effective in reducing the SARA scores (MD = - 3.45, 95%CI = [- 4.85, - 2.50], P < 0.05) and ICARS scores (MD = - 10.87, 95%CI = [- 14.46, - 7.28], P < 0.05) in patients with cerebellar ataxia compared to controls. Subgroup analysis showed that the efficacy of tDCS and rTMS was statistically different in patients with cerebellar ataxia as assessed by the SARA scores, but not by the ICARS scores. There was statistically significant difference in the efficacy of NIBS for the treatment of cerebellar ataxia caused by different etiologies. As for safety, 8 of 14 included studies documented the adverse effects of NIBS, and only two studies reported the mild adverse events of NIBS.
CONCLUSIONS
Cerebellar NIBS was safe and effective in improving the motor coordination of patients with cerebellar ataxia, and tDCS was better than rTMS in the treatment of cerebellar ataxia. In addition, the efficacy of NIBS was different in the treatment of different types of cerebellar ataxia.
Topics: Humans; Cerebellar Ataxia; Randomized Controlled Trials as Topic; Transcranial Magnetic Stimulation; Transcranial Direct Current Stimulation; Cerebellum
PubMed: 37460852
DOI: 10.1007/s00415-023-11799-8 -
Neuroradiology Feb 2015Neuroimaging techniques including structural magnetic resonance imaging (MRI) and functional positron emission tomography (PET) are useful in categorizing various... (Review)
Review
PURPOSE
Neuroimaging techniques including structural magnetic resonance imaging (MRI) and functional positron emission tomography (PET) are useful in categorizing various midbrain-hindbrain (MHB) malformations, both in allowing diagnosis and in helping to understand the developmental processes that were disturbed. Brain imaging phenotypes of numerous malformations are characteristic features that help in guiding the genetic testing in case of direct neuroimaging-genotype correlation or, at least, to differentiate among MHB malformations entities. The present review aims to provide the reader with an update of the use of neuroimaging applications in the fine analysis of MHB malformations, using a comprehensive, recently proposed developmental and genetic classification.
METHODS
We have performed an extensive systematic review of the literature, from the embryology main steps of MHB development through the malformations entities, with regard to their molecular and genetic basis, conventional MRI features, and other neuroimaging characteristics.
RESULTS
We discuss disorders in which imaging features are distinctive and how these features reflect the structural and functional impairment of the brain.
CONCLUSION
Recognition of specific MRI phenotypes, including advanced imaging features, is useful to recognize the MHB malformation entities, to suggest genetic investigations, and, eventually, to monitor the disease outcome after supportive therapies.
Topics: Humans; Magnetic Resonance Imaging; Mesencephalon; Nervous System Malformations; Neuroimaging; Rhombencephalon
PubMed: 25339235
DOI: 10.1007/s00234-014-1431-2 -
Cerebellum (London, England) Dec 2023To date, cerebellar contribution to language is well established via clinical and neuroimaging studies. However, the particular functional role of the cerebellum in... (Meta-Analysis)
Meta-Analysis Review
To date, cerebellar contribution to language is well established via clinical and neuroimaging studies. However, the particular functional role of the cerebellum in language remains to be clarified. In this study, we present the first systematic review of the diverse language symptoms in spoken language after cerebellar lesion that were reported in case studies for the last 30 years (18 clinical cases from 13 papers), and meta-analysis using cluster analysis with bootstrap and symptom co-occurrence analysis. Seven clusters of patients with similar language symptoms after cerebellar lesions were found. Co-occurrence analysis revealed pairs of symptoms that tend to be comorbid. Our results imply that the "linguistic cerebellum" has a multiform contribution to language function. The most possible mechanism of such contribution is the cerebellar reciprocal connectivity with supratentorial brain regions, where the cerebellar level of the language network has a general modulation function and the supratentorial level is more functionally specified. Based on cerebellar connectivity with supratentorial components of the language network, the "linguistic cerebellum" might be further functionally segregated.
Topics: Humans; Language; Cerebellum; Language Disorders; Linguistics; Brain; Magnetic Resonance Imaging
PubMed: 36205825
DOI: 10.1007/s12311-022-01482-5 -
Cerebellum (London, England) Dec 2022Essential tremor (ET) is one of the most common movement disorders. Over the last 10 years, magnetic resonance imaging (MRI) has shed light on the structural and... (Review)
Review
Essential tremor (ET) is one of the most common movement disorders. Over the last 10 years, magnetic resonance imaging (MRI) has shed light on the structural and functional abnormalities possibly involved in ET pathophysiology. In this systematic review, we aimed to identify the cortical and subcortical structures involved and the role that different brain areas play in the pathophysiology of motor and non-motor ET features. We found that structural (grey and white matter) cerebellar damage and connectivity alterations between the cerebellum and various cortical areas play a role in both motor and non-motor symptoms of ET. In particular, many studies found an association between MRI findings and non-motor symptoms.
Topics: Humans; Essential Tremor; Neuroimaging; Magnetic Resonance Imaging; Brain; Cerebellum
PubMed: 34657271
DOI: 10.1007/s12311-021-01335-7 -
Neurosurgical Review Jul 2023The dentato-rubro-olivary pathway, also known as the Guillain-Mollaret triangle (GMT) or myoclonic triangle, consists of the dentate nucleus, the red nucleus, and the... (Review)
Review
The dentato-rubro-olivary pathway, also known as the Guillain-Mollaret triangle (GMT) or myoclonic triangle, consists of the dentate nucleus, the red nucleus, and the inferior olivary nucleus (ION). GMT is important for motor coordination and control, and abnormalities in this network can lead to various neurological disorders. The present study followed a systematic approach in conducting a review on GMT studies. The inclusion criteria were limited to human subjects with primary objectives of characterizing and evaluating GMT syndromes, and the methodology used was not a determining factor for eligibility. The search strategy used MeSH terms and keywords relevant to the study's objective in various databases until August 2022. A total of 76 studies were included in the review after assessing 527 articles for eligibility based on the final inclusion criteria. Most of the studies evaluated the GMT in human subjects, with the majority utilizing magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), or combination of them. The review found that Hypertrophic olivary degeneration (HOD), a common consequence of GMT damage, has diverse underlying causes, including stroke, brainstem cavernous malformations, and structural impairments. Palatal tremor, ocular myoclonus, ataxia, nystagmus, and vertigo were frequently reported symptoms associated with HOD. This systematic review provides comprehensive insights into the association between GMT and various neurological syndromes, shedding light on the diagnostic, etiological, and prognostic aspects of GMT dysfunction. Understanding the role of the GMT and its implications in movement disorders could pave the way for improved treatment options and better management of neurological conditions related to this critical brainstem pathway.
Topics: Humans; Diffusion Tensor Imaging; Syndrome; Olivary Nucleus; Magnetic Resonance Imaging; Stroke; Hypertrophy
PubMed: 37468768
DOI: 10.1007/s10143-023-02086-1 -
Journal of Neurology Sep 2017Listeria monocytogenes is associated with rhombencephalitis. However, the exact mechanisms of brainstem invasion remains poorly understood. Here, we demonstrate clinical... (Review)
Review
Listeria monocytogenes is associated with rhombencephalitis. However, the exact mechanisms of brainstem invasion remains poorly understood. Here, we demonstrate clinical and radiological data suggesting that Listeria may invade the brainstem via the trigeminal nerve. Three females (41, 64 and 70 years) with culture proven L. monocytogenes bacteremia and rhombencephalitis were investigated in the period of 2014-16. T2-weighted and contrast-enhanced T1-weighted MRI revealed a cerebellopontine abscess in all three patients, including the involvement of the trigeminal nerve root. In two patients, MRI also revealed selective contrast enhancement of the sensory trigeminal tract in the pons and medulla oblongata. Prior to any other neurological symptoms, two patients complained of hypoesthesia and a tingling sensation in the ipsilateral half of the face, consistent with sensory trigeminal nerve dysfunction on that side. In addition, we identified another 120 cases of Listeria rhombencephalitis following a systematic review. Cranial nerves VII, V, IX, and X, respectively, medulla oblongata, cerebellum and pons, were the most frequently involved brain structures. The present clinical and radiological findings corroborate earlier data from animal experiments, indicating that L. monocytogenes may be capable of retrograde intra-axonal migration along the cranial nerves. We suggest that in a subset of patients with rhombencephalitis L. monocytogenes enters the cerebellopontine angle through the trigeminal nerve, invading the brainstem via the sensory trigeminal nuclei.
Topics: Adult; Aged; Encephalitis; Female; Humans; Listeria monocytogenes; Magnetic Resonance Imaging; Meningitis, Listeria; Middle Aged; Rhombencephalon; Trigeminal Nerve
PubMed: 28730571
DOI: 10.1007/s00415-017-8572-2 -
The Journal of Maternal-fetal &... Oct 2017The cerebellum is essential for normal neurodevelopment and is particularly susceptible for intra-uterine disruptions. Although some causal prenatal exposures have been... (Review)
Review
PURPOSE
The cerebellum is essential for normal neurodevelopment and is particularly susceptible for intra-uterine disruptions. Although some causal prenatal exposures have been identified, the origin of neurodevelopmental disorders remains mostly unclear. Therefore, a systematic literature search was conducted to provide an overview of parental environmental exposures and intrinsic factors influencing prenatal cerebellar growth and development in humans.
MATERIALS AND METHODS
The literature search was limited to human studies in the English language and was conducted in Embase, Medline, Cochrane, Web of Science, Pubmed and GoogleScholar. Eligible studies were selected by three independent reviewers and study quality was scored by two independent reviewers.
RESULTS
The search yielded 3872 articles. We found 15 eligible studies reporting associations between cerebellar development and maternal smoking (4), use of alcohol (3), in vitro fertilization mediums (1), mercury (1), mifepristone (2), aminopropionitriles (1), ethnicity (2) and cortisol levels (1). No studies reported on paternal factors.
CONCLUSIONS
Current literature on associations between parental environmental exposures, intrinsic factors and human cerebellar development is scarce. Yet, this systematic review provided an essential overview of human studies demonstrating the vulnerability of the cerebellum to the intra-uterine environment.
Topics: Cerebellum; Female; Humans; Maternal Exposure; Pregnancy; Prenatal Injuries
PubMed: 27806674
DOI: 10.1080/14767058.2016.1253060 -
Cerebellum (London, England) Oct 2023The effectiveness of cerebellar repetitive transcranial magnetic stimulation (rTMS) on motor dysfunction in patients with neurological disorders has received increasing... (Review)
Review
The effectiveness of cerebellar repetitive transcranial magnetic stimulation (rTMS) on motor dysfunction in patients with neurological disorders has received increasing attention because of its potential for neuromodulation. However, studies on the neuromodulatory effects, parameters, and safety of rTMS implementation in the cerebellum to alleviate motor dysfunction are limited. This systematic review aimed to evaluate the effectiveness and safety of cerebellar rTMS treatment for motor dysfunction caused by neurological disorders and to review popular stimulation parameters. Five electronic databases-Medline, Web of Science, Scopus, Cochrane Library, and Embase-were searched for relevant research published from inception to July 2022. All randomized controlled trials (RCTs) that reported the effects of cerebellar rTMS combined with behavioral rating scales on motor dysfunction were eligible for enrollment. Additionally, reference lists of the enrolled studies were manually checked. Among 1156 articles screened, 21 RCTs with 666 subjects were included. rTMS conducted on the cerebellum showed an improvement in stroke (spasticity, balance, and gait), cervical dystonia, Parkinson's disease (tremor), cerebellar ataxia, and essential tremor but not in multiple sclerosis. The 8-shaped coil with a diameter of 70 mm was determined as the most common therapeutic choice. None of the studies reported severe adverse events except mild side effects in three. Therefore, rTMS appears to be a promising and safe technique for the treatment of motor dysfunction, targeting the cerebellum to induce motor behavioral improvement. Further rigorous RCTs, including more samples and longer follow-up periods, are required to precisely explore the effective stimulation parameters and possible mechanisms.
Topics: Humans; Transcranial Magnetic Stimulation; Cerebellum; Essential Tremor; Parkinson Disease; Stroke
PubMed: 36018543
DOI: 10.1007/s12311-022-01465-6 -
Neuroscience and Biobehavioral Reviews Dec 2017The locus coeruleus (LC), the major origin of noradrenergic modulation of the central nervous system, innervates extensive areas throughout the brain and is implicated... (Review)
Review
The locus coeruleus (LC), the major origin of noradrenergic modulation of the central nervous system, innervates extensive areas throughout the brain and is implicated in a variety of autonomic and cognitive functions. Alterations in the LC-noradrenergic system have been associated with healthy ageing and neuropsychiatric disorders including Parkinson's disease, Alzheimer's disease and depression. The last decade has seen advances in imaging the structure and function of the LC, and this paper systematically reviews the methodology and outcomes of sixty-nine structural and functional MRI studies of the LC in humans. Structural MRI studies consistently showed lower LC signal intensity and volume in clinical groups compared to healthy controls. Within functional studies, the LC was activated by a variety of tasks/stimuli and had functional connectivity to a range of brain regions. However, reported functional LC location coordinates were widely distributed compared to previously published neuroanatomical locations. Methodological and demographic factors potentially contributing to these differences are discussed, together with recommendations to optimize the reliability and validity of future LC imaging studies.
Topics: Humans; Image Processing, Computer-Assisted; Locus Coeruleus; Magnetic Resonance Imaging
PubMed: 29107830
DOI: 10.1016/j.neubiorev.2017.10.023 -
Cerebellum (London, England) Oct 2023The cerebellum's role in affective processing is increasingly recognized in the literature, but remains poorly understood, despite abundant clinical evidence for... (Meta-Analysis)
Meta-Analysis
The cerebellum's role in affective processing is increasingly recognized in the literature, but remains poorly understood, despite abundant clinical evidence for affective disruptions following cerebellar damage. To improve the characterization of emotion processing and investigate how attention allocation impacts this processing, we conducted a meta-analysis on task activation foci using GingerALE software. Eighty human neuroimaging studies of emotion including 2761 participants identified through Web of Science and ProQuest databases were analyzed collectively and then divided into two categories based on the focus of attention during the task: explicit or implicit emotion processing. The results examining the explicit emotion tasks identified clusters within the posterior cerebellar hemispheres (bilateral lobule VI/Crus I/II), the vermis, and left lobule V/VI that were likely to be activated across studies, while implicit tasks activated clusters including bilateral lobules VI/Crus I/II, right Crus II/lobule VIII, anterior lobule VI, and lobules I-IV/V. A direct comparison between these categories revealed five overlapping clusters in right lobules VI/Crus I/Crus II and left lobules V/VI/Crus I of the cerebellum common to both the explicit and implicit task contrasts. There were also three clusters activated significantly more for explicit emotion tasks compared to implicit tasks (right lobule VI, left lobule VI/vermis), and one cluster activated more for implicit than explicit tasks (left lobule VI). These findings support previous studies indicating affective processing activates both the lateral hemispheric lobules and the vermis of the cerebellum. The common and distinct activation of posterior cerebellar regions by tasks with explicit and implicit attention demonstrates the supportive role of this structure in recognizing, appraising, and reacting to emotional stimuli.
Topics: Humans; Cerebellum; Emotions; Cerebellar Vermis; Magnetic Resonance Imaging; Neuroimaging; Brain Mapping
PubMed: 35999332
DOI: 10.1007/s12311-022-01459-4