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Cerebellum (London, England) Dec 2023Current understanding of anti-Yo/PCA1 antibody-associated cerebellar ataxia is based on case reports and small case series. Our goal was to summarize clinical features,... (Review)
Review
Current understanding of anti-Yo/PCA1 antibody-associated cerebellar ataxia is based on case reports and small case series. Our goal was to summarize clinical features, highlighting atypical presentations and gaps of knowledge. Following the PRISMA guidelines, we systematically screened Pubmed/MEDLINE, Embase, Scopus, and Web of Science from inception to April 2022 for all case reports and series concerning anti-Yo antibody-associated cerebellar ataxia. We collected data on clinical presentation, investigation findings, and treatment outcomes. Of 379 included patients, 96% were female with gynecologic cancer (82%). Among men, 87% had an associated tumor, mainly of gastrointestinal origin. The median age was 60 years old. Pancerebellar ataxia was the main clinical feature, but extracerebellar findings were frequent during the disease course. Vertigo and imbalance can be present early in the disease course in about two thirds of patients, as a prodromal phase. Although neuroimaging usually is normal or shows cerebellar atrophy, inflammatory changes may also be present. More than half of the patients reported some improvement after immunotherapy. However, despite treatment, 84% of survivors were unable to walk unassisted on follow-up. Our study provides objective data and advances in current knowledge of anti-Yo antibody-associated cerebellar ataxia such as the description of prodromal symptoms, extracerebellar findings, and its presentations in males.
Topics: Male; Middle Aged; Humans; Female; Cerebellar Ataxia; Paraneoplastic Cerebellar Degeneration; Purkinje Cells; Cerebellar Diseases; Neoplasms; Autoantibodies; Disease Progression
PubMed: 36334195
DOI: 10.1007/s12311-022-01492-3 -
International Journal of Stroke :... Feb 2019Amplifying endogenous neuroprotective mechanisms is a promising avenue for stroke therapy. One target is mammalian target of rapamycin (mTOR), a serine/threonine kinase... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Amplifying endogenous neuroprotective mechanisms is a promising avenue for stroke therapy. One target is mammalian target of rapamycin (mTOR), a serine/threonine kinase regulating cell proliferation, cell survival, protein synthesis, and autophagy. Animal studies investigating the effect of rapamycin on mTOR inhibition following cerebral ischemia have shown conflicting results.
AIM
To conduct a systematic review and meta-analysis evaluating the effectiveness of rapamycin in reducing infarct volume in animal models of ischemic stroke.
SUMMARY OF REVIEW
Our search identified 328 publications. Seventeen publications met inclusion criteria (52 comparisons: 30 reported infarct size and 22 reported neurobehavioral score). Study quality was modest (median 4 of 9) with no evidence of publication bias. The point estimate for the effect of rapamycin was a 21.6% (95% CI, 7.6%-35.7% p < 0.01) improvement in infarct volume and 30.5% (95% CI 17.2%-43.8%, p < 0.0001) improvement in neuroscores. Effect sizes were greatest in studies using lower doses of rapamycin.
CONCLUSION
Low-dose rapamycin treatment may be an effective therapeutic option for stroke. Modest study quality means there is a potential risk of bias. We recommend further high-quality preclinical studies on rapamycin in stroke before progressing to clinical trials.
Topics: Animals; Brain Ischemia; Cerebellum; Disease Models, Animal; Humans; Immunosuppressive Agents; Neuroprotective Agents; Sirolimus; Stroke; TOR Serine-Threonine Kinases
PubMed: 30489210
DOI: 10.1177/1747493018816503 -
Developmental Medicine and Child... Apr 2009Cerebellar malformations are increasingly diagnosed in the fetal period. Consequently, their consideration requires stressful and often critical decisions from both... (Review)
Review
Cerebellar malformations are increasingly diagnosed in the fetal period. Consequently, their consideration requires stressful and often critical decisions from both clinicians and families. This has resulted in an emergent need to understand better the impact of these early life lesions on child development. We performed a comprehensive literature search of studies describing neurodevelopmental outcomes of cerebellar malformations between January 1997 and December 2007. Overall, the data suggested that children with isolated inferior vermis hypoplasia (IVH) and mega cisterna magna (MCM) have a good developmental outcome, whereas children with molar tooth sign/Joubert syndrome, vermis hypoplasia, pontocerebellar hypoplasia (PCH) type II, and cerebellar agenesis experience moderate to severe global developmental delays. Reports for Dandy-Walker malformation (DWM) were conflicting; however, the presence of a normally lobulated vermis and the absence of associated brain anomalies were associated with a more favourable outcome. Finally, children with isolated cerebellar hypoplasia experienced fewer impairments. Important methodological limitations highlighted include a lack of standardized outcome measure use in 79% of studies and the predominant use of retrospective study designs (85%), with 40% limited to case reports or case-series. In summary, rigorous outcome studies describing the spectrum of disabilities in survivors are urgently needed to accurately delineate the long-term neurodevelopmental consequences of cerebellar malformations.
Topics: Cerebellar Diseases; Cerebellum; Child; Child, Preschool; Developmental Disabilities; Female; Humans; Infant; Infant, Newborn; Male; Pregnancy; Retrospective Studies
PubMed: 19191827
DOI: 10.1111/j.1469-8749.2008.03224.x -
BMC Neurology Feb 2022Intra-cranial schwannomas account for less than 8% of brain tumors, among which more than 80% arise from the vestibular nerve. Intra-cerebellar schwannomas are extremely...
BACKGROUND
Intra-cranial schwannomas account for less than 8% of brain tumors, among which more than 80% arise from the vestibular nerve. Intra-cerebellar schwannomas are extremely rare. Several cases have been previously reported but without remarkable degenerative changes on histology.
CASE PRESENTATION
A 61-year-old man presented with worsening disorientation, and an imaging study revealed a cystic lesion (6.5 cm in the largest diameter) in the left hemisphere of the cerebellum accompanied by a mural nodule (2.5 cm) located just inside the skull with enhancement and focal calcification, in addition to hydrocephalus. The lesion was more than 5 mm from the left acoustic nerve. The patient underwent gross total resection. Pathological examination revealed remarkable degenerative changes with various morphological features. Tumor cells were pleomorphic with rich cytoplasm containing numerous eosinophilic granules. Blood vessels and extracellular matrix showed remarkable hyalinization. Immunohistochemical staining revealed that the tumor cells were positive for S-100 protein and negative for Olig2. The tumor was diagnosed as a schwannoma with marked degenerative changes.
CONCLUSIONS
The present case is discussed with reference to a systematic review of previous reports of intra-cerebellar schwannoma. Intra-cerebellar schwannoma should be included in the differential diagnosis of cystic lesions with heterogeneous histopathological morphology in the cerebellum.
Topics: Brain Neoplasms; Calcinosis; Cerebellum; Diagnosis, Differential; Humans; Male; Middle Aged; Neurilemmoma
PubMed: 35209854
DOI: 10.1186/s12883-022-02596-3 -
Acta Neurologica Scandinavica Nov 2022Restless Legs Syndrome (RLS) is a sleep-related movement disorder, which can also result from brainstem pathology. A systematic review of articles published in the... (Review)
Review
Restless Legs Syndrome (RLS) is a sleep-related movement disorder, which can also result from brainstem pathology. A systematic review of articles published in the electronic databases PubMed and Web of Science was conducted to summarize the existent literature on RLS associated with a brainstem stroke. We identified eight articles including 19 subjects with RLS due to brainstem ischemic lesion. The symptoms occurred simultaneously with the infarction (66.7%) or few days after (33.3%). The most common location of infarction was pons and less commonly medulla. In most cases (68.4%), symptoms were unilateral. In the majority of those cases (92.3%), the contralateral limb was affected due to a lateral pons infarction. RLS symptoms after infarction improved or resolved in almost 90% of cases within a few days up to 3 months. In almost all patients who received dopaminergic treatment (11 out of 13, 91.7%), the symptoms improved significantly or resolved completely. Screening for RLS has to be considered in patients suffering a brainstem stroke, particularly anteromedial pontine infarction. The appearance of acute unilateral RLS symptoms, usually in association with other sensorimotor deficits, should prompt the clinician to consider a vascular event in the brainstem. RLS in these cases seem to have a favorable outcome and respond well to dopaminergic treatment.
Topics: Brain Stem Infarctions; Dopamine; Humans; Pons; Restless Legs Syndrome; Stroke
PubMed: 36063288
DOI: 10.1111/ane.13702 -
Neurosurgical Review Feb 2021The cerebellum is historically implicated in motor coordination, but accumulating modern evidence indicates involvement in non-motor domains, including cognition,...
The cerebellum is historically implicated in motor coordination, but accumulating modern evidence indicates involvement in non-motor domains, including cognition, emotion, and language. This correlates with the symptoms observed in postoperative cerebellar mutism syndrome (CMS). Profound knowledge of cerebellar functional topography and tractography is important when approaching cerebellar tumors, as surgical trauma to relevant structures of cerebellar pathways plays a role in the pathogenesis of CMS. The aim of this systematic review is to provide a concise overview of relevant modern neuroimaging data and cerebellar functional tracts with regard to neurosurgical procedures.
Topics: Cerebellum; Humans; Neural Pathways; Neuroimaging; Neurosurgeons; Neurosurgical Procedures
PubMed: 32056026
DOI: 10.1007/s10143-020-01242-1 -
Systematic Reviews Jun 2020Vestibular compensation is a homeostatic process that occurs in the central nervous system in response to peripheral vestibular dysfunction. Experimental studies in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Vestibular compensation is a homeostatic process that occurs in the central nervous system in response to peripheral vestibular dysfunction. Experimental studies in rodent models have suggested that unilateral peripheral vestibular lesions are correlated with an increase in the intrinsic excitability of central vestibular neurons. This process may be dependent on the intrinsic properties of the neurons themselves. We aimed to conduct a systematic review of the literature to survey the evidence for changes in intrinsic plasticity observed during the acute phase of vestibular compensation.
METHODS
We systematically reviewed the literature regarding the electrophysiological effect of experimentally induced unilateral vestibular deafferentation (UVD) on the intrinsic membrane properties of medial vestibular nucleus neurons in animal models. We developed tools to assess the methodological quality (precision, validity and bias) of studies that met pre-determined inclusion and exclusion criteria. We extracted numerical data and performed a meta-analysis of specific quantitative data pooled from these studies.
RESULTS
We identified 17 studies that satisfied the inclusion criteria. There is moderate quality evidence to suggest a statistically significant increase in the intrinsic excitability of medial vestibular nucleus neurons following unilateral vestibular deafferentation. Specifically, the spontaneous discharge rate increases by 4 spikes/s on average and the sensitivity to current stimuli increases.
CONCLUSION
Using this novel approach, we demonstrate that the methodology of systematic review and meta-analysis is a useful tool in the summation of data across experimental animal studies with similar aims.
Topics: Animals; Denervation; Neuronal Plasticity; Neurons; Vestibular Nuclei
PubMed: 32552855
DOI: 10.1186/s13643-020-01399-2 -
Neurology Feb 2019To study hematoma location and morphology of intracerebral hemorrhage (ICH) associated with oral anticoagulants (OAC) and delineate causes and mechanism.
OBJECTIVE
To study hematoma location and morphology of intracerebral hemorrhage (ICH) associated with oral anticoagulants (OAC) and delineate causes and mechanism.
METHODS
We performed a systematic literature research and meta-analysis of studies comparing neuroimaging findings in patients with OAC-ICH compared to those with ICH not associated with OAC (non-OAC ICH). We calculated pooled risk ratios (RRs) for ICH location using the Mantel-Haenszel random-effects method and corresponding 95% confidence intervals (95% CI).
RESULTS
We identified 8 studies including 6,259 patients (OAC-ICH n = 1,107, pooled OAC-ICH population 17.7%). There was some evidence for deep ICH location (defined as ICH in the thalamus, basal ganglia, internal capsule, or brainstem) being less frequent in patients with OAC-ICH (OAC-ICH: 450 of 1,102/40.8% vs non-OAC ICH: 2,656 of 4,819/55.1%; RR 0.94, 95% CI 0.88-1.00, = 0.05, = 0%) while cerebellar ICH location was significantly more common in OAC-ICH (OAC-ICH: 111 of 1,069/10.4% vs non-OAC ICH: 326 of 4,787/6.8%; RR 1.45, 95% CI 1.12-1.89, = 0.005, = 21%) compared to non-OAC ICH. There was no statistically significant relationship to OAC use for lobar (OAC-ICH: 423 of 1,107/38.2% vs non-OAC ICH: 1,884 of 5,152/36.6%; RR 1.02, 95% CI 0.89-1.17, = 0.75, = 53%, for heterogeneity = 0.04) or brainstem ICH (OAC-ICH: 36 of 546/6.6% vs non-OAC ICH: 172 of 2,626/6.5%; RR 1.04, 95% CI 0.58-1.87, = 0.89, = 59%, for heterogeneity = 0.04). The risk for intraventricular extension (OAC-ICH: 436 of 840/51.9% vs non-OAC ICH: 1,429 of 3,508/40.7%; RR 1.26, 95% CI 1.16-1.36, < 0.001, = 0%) was significantly increased in patients with OAC-ICH. We found few data on ICH morphology in OAC-ICH vs non-OAC ICH.
CONCLUSION
The overrepresentation of cerebellar ICH location and intraventricular extension in OAC-ICH might have mechanistic relevance for the underlying arteriopathy, pathophysiology, or bleeding pattern of OAC-ICH, and should be investigated further.
Topics: Administration, Oral; Anticoagulants; Basal Ganglia Hemorrhage; Brain; Brain Stem; Case-Control Studies; Cerebellum; Cerebral Hemorrhage; Hematoma; Humans; Internal Capsule; Thalamus
PubMed: 30674603
DOI: 10.1212/WNL.0000000000006958 -
Cerebellum (London, England) Oct 2023The cerebellum is involved in regulating motor, affective, and cognitive processes. It is a promising target for transcranial direct current stimulation (tDCS)... (Review)
Review
BACKGROUND
The cerebellum is involved in regulating motor, affective, and cognitive processes. It is a promising target for transcranial direct current stimulation (tDCS) intervention in stroke.
OBJECTIVES
To review the current evidence for cerebellar tDCS (ctDCS) in stroke, its problems, and its future directions.
METHODS
We searched the Web of Science, MEDLINE, CINAHL, EMBASE, Cochrane Library, and PubMed databases. Eligible studies were identified after a systematic literature review of the effects of ctDCS in stroke patients. The changes in assessment scale scores and objective indicators after stimulation were reviewed.
RESULTS
Eleven studies were included in the systematic review, comprising 169 stroke patients. Current evidence suggests that anode tDCS on the right cerebellar hemisphere does not appear to enhance language processing in stroke patients. Compared with the sham group, stroke patients showed a significant improvement in the verb generation task after cathodal ctDCS stimulation. However, with regard to naming, two studies came to the opposite conclusion. The contralesional anodal ctDCS is expected to improve standing balance but not motor learning in stroke patients. The bipolar bilateral ctDCS protocol to target dentate nuclei (PO10h and PO9h) had a positive effect on standing balance, goal-directed weight shifting, and postural control in stroke patients.
CONCLUSIONS
ctDCS appears to improve poststroke language and motor dysfunction (particularly gait). However, the evidence for these results was insufficient, and the quality of the relevant studies was low. ctDCS stimulation parameters and individual factors of participants may affect the therapeutic effect of ctDCS. Researchers need to take a more regulated approach in the future to conduct studies with large sample sizes. Overall, ctDCS remains a promising stroke intervention technique that could be used in the future.
Topics: Humans; Transcranial Direct Current Stimulation; Cerebellum; Stroke; Language; Postural Balance
PubMed: 36028789
DOI: 10.1007/s12311-022-01464-7 -
Neurological Sciences : Official... Aug 2023Procedural perceptual-motor learning of sequences (PPMLS) provides perceptual-motor skills in many activities of daily living. Based on behavioral and neuroimaging... (Review)
Review
INTRODUCTION
Procedural perceptual-motor learning of sequences (PPMLS) provides perceptual-motor skills in many activities of daily living. Based on behavioral and neuroimaging results, theoretical models of PPMLS postulate that the cortico-striatal loop, the cortico-cerebellar loop and the hippocampus are specifically involved in the early stage of PPMLS while the cortico-striatal loop would be specifically involved in the late stage of PPMLS. Hence, current models predict that the early stage of PPMLS should be impaired in Parkinson's disease (PD: lesion of the cortico-striatal loop), in cerebellar disease (CD: lesion of the cortico-cerebellar loop) and in Alzheimer's disease (AD: lesion of the hippocampus), whereas the late stage of PPMLS should be specifically impaired in PD.
OBJECTIVE
The aim of the study is (1) to draw a complete picture of experimental results on PPMLS in PD, CD and AD (2) to understand heterogeneity of results as regard to participant and task characteristics.
METHOD
This review is based on the guideline proposed by the PRISMA statement.
RESULTS
Our review reveals (1) that the experimental results clarify the theoretical models and (2) that the impairment of PPMLS depends on both the personal characteristics of the participants and the characteristics of the task to-be-learnt rather than on the disease itself.
CONCLUSION
Our results highlight that these characteristics should be more carefully considered to understand the heterogeneity of results across studies on PPMLS and the effects of rehabilitation programs.
Topics: Humans; Activities of Daily Living; Learning; Parkinson Disease; Motor Skills; Cerebellum
PubMed: 36973591
DOI: 10.1007/s10072-023-06724-w