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Qatar Medical Journal 2021The central nervous system is an unusual location of sarcoidosis, which commonly affects the cranial nerves, meninges, hypothalamus, and pituitary gland. Involvement of...
BACKGROUND
The central nervous system is an unusual location of sarcoidosis, which commonly affects the cranial nerves, meninges, hypothalamus, and pituitary gland. Involvement of the pineal region is extremely rare. This systematic review focused on the diagnosis and management of pineal region sarcoidosis, dorsal mesencephalon, and periaqueductal region.
OBJECTIVES
This study aimed to discuss diagnostic modalities and best management tools of the aforementioned pathology.
METHODS
ScienceDirect, PubMed, and Google Scholar databases were searched for English or French articles about sarcoidosis of the pineal region, dorsal mesencephalon, and periaqueductal region. The clinical case of a patient managed at our department that we believe is directly relevant to this review is also presented. Patients' demographics, clinical presentations, presence of hydrocephalus, other sarcoidosis locations in the central nervous system, and medical treatment were collected. Surgical management, surgical approach, and outcomes and complications of each procedure were also obtained. This study was conducted in agreement with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.
RESULTS
Fifteen cases were examined. The study sample consisted of nine (60%) male and six (40%) female, and the mean age was 32 years. Eight (53%) patients had hydrocephalus, and the predominant clinical presentations were signs of increasing intracranial pressure (headaches, vomiting, and papilledema). Six (40%) patients had diplopia, and convergence-retraction nystagmus was noted in three (20%) patients. Argyll Robertson sign was present in one patient and suspected in another patient (13%). Medical treatment consisted mainly of steroids (93% of cases). Open surgery on the pineal region was performed in five patients, and four of them reported to have serious complications (such as ophthalmoplegia, hemianopsia, hemiparesis, bilateral third cranial nerve paresis, and cerebellar syndrome). Endoscopic management was performed in two patients without complications.
CONCLUSION
To treat hydrocephalus, brain imaging is mandatory in patients with sarcoidosis if intracranial hypertension is suspected. In pineal region sarcoidosis, management of hydrocephalus is the priority, followed by medical treatment of the lesion. Open surgery of any approach presents a high risk of complications; thus, an endoscopic approach is the preferred management, as it treats hydrocephalus and makes biopsy possible with minimal risk.
PubMed: 34466394
DOI: 10.5339/qmj.2021.29 -
Neuroscience and Biobehavioral Reviews Jan 2022Although schizophrenia is associated with increased presynaptic dopamine function in the striatum, it remains unclear if neuromelanin levels, which are thought to serve... (Meta-Analysis)
Meta-Analysis Review
Although schizophrenia is associated with increased presynaptic dopamine function in the striatum, it remains unclear if neuromelanin levels, which are thought to serve as a biomarker for midbrain dopamine neuron function, are increased in patients with schizophrenia. We conducted a systematic review and meta-analysis of magnetic resonance imaging (MRI) and postmortem studies comparing neuromelanin (NM) levels between patients with schizophrenia and healthy controls (HCs). Standard mean differences were calculated to assess group differences in NM accumulation levels between patients with schizophrenia and HCs. This study included 7 articles in total. Five studies employed NM-sensitive MRI (NM-MRI) and two were postmortem brain studies. The patient group (n = 163) showed higher NM levels in the substantia nigra (SN) than HCs (n = 228) in both the analysis of the seven studies and the subgroup analysis of the 5 NM-MRI studies. This analysis suggest increased NM levels in the SN may be a potential biomarker for stratifying schizophrenia, warranting further research that accounts for the heterogeneity of this disorder.
Topics: Humans; Magnetic Resonance Imaging; Melanins; Schizophrenia; Substantia Nigra
PubMed: 34718049
DOI: 10.1016/j.neubiorev.2021.10.028 -
Toxicology and Applied Pharmacology Feb 2013Parkinson disease (PD) is a debilitating neurodegenerative motor disorder, with its motor symptoms largely attributable to loss of dopaminergic neurons in the substantia... (Review)
Review
Parkinson disease (PD) is a debilitating neurodegenerative motor disorder, with its motor symptoms largely attributable to loss of dopaminergic neurons in the substantia nigra. The causes of PD remain poorly understood, although environmental toxicants may play etiologic roles. Solvents are widespread neurotoxicants present in the workplace and ambient environment. Case reports of parkinsonism, including PD, have been associated with exposures to various solvents, most notably trichloroethylene (TCE). Animal toxicology studies have been conducted on various organic solvents, with some, including TCE, demonstrating potential for inducing nigral system damage. However, a confirmed animal model of solvent-induced PD has not been developed. Numerous epidemiologic studies have investigated potential links between solvents and PD, yielding mostly null or weak associations. An exception is a recent study of twins indicating possible etiologic relations with TCE and other chlorinated solvents, although findings were based on small numbers, and dose-response gradients were not observed. At present, there is no consistent evidence from either the toxicological or epidemiologic perspective that any specific solvent or class of solvents is a cause of PD. Future toxicological research that addresses mechanisms of nigral damage from TCE and its metabolites, with exposure routes and doses relevant to human exposures, is recommended. Improvements in epidemiologic research, especially with regard to quantitative characterization of long-term exposures to specific solvents, are needed to advance scientific knowledge on this topic.
Topics: Animals; Dopaminergic Neurons; Environmental Exposure; Humans; Parkinson Disease, Secondary; Solvents; Substantia Nigra; Trichloroethylene; Twin Studies as Topic
PubMed: 23220449
DOI: 10.1016/j.taap.2012.11.016 -
Scientific Reports Feb 2016A large number of articles have reported substantia nigra hyperechogenicity in Parkinson's disease (PD) and have assessed the diagnostic accuracy of transcranial... (Meta-Analysis)
Meta-Analysis Review
A large number of articles have reported substantia nigra hyperechogenicity in Parkinson's disease (PD) and have assessed the diagnostic accuracy of transcranial sonography (TCS); however, the conclusions are discrepant. Consequently, this systematic review and meta-analysis aims to consolidate the available observational studies and provide a comprehensive evaluation of the clinical utility of TCS in PD. Totally, 31 studies containing 4,386 participants from 13 countries were included. A random effects model was utilized to pool the effect sizes. Meta-regression and sensitivity analysis were performed to explore potential heterogeneity. Overall diagnostic accuracy of TCS in differentiating PD from normal controls was quite high, with a pooled sensitivity of 0.83 (95% CI: 0.81-0.85) and a pooled specificity of 0.87 (95% CI: 0.85-0.88). The positive likelihood ratio, the negative likelihood ratio and diagnostic odds ratio were calculated 6.94 (95% CI: 5.09-9.48), 0.19 (95% CI: 0.16-0.23), and 42.89 (95% CI: 30.03-61.25) respectively. Our systematic review of the literature and meta-analysis suggest that TCS has high diagnostic accuracy in the diagnosis of PD when compared to healthy control.
Topics: Humans; Parkinson Disease; Publication Bias; ROC Curve; Reproducibility of Results; Substantia Nigra; Ultrasonography, Doppler, Transcranial
PubMed: 26878893
DOI: 10.1038/srep20863 -
Biology of Sex Differences Nov 2022In recent decades, increasing longevity (among other factors) has fostered a rise in Parkinson's disease incidence. Although not exhaustively studied in this devastating... (Meta-Analysis)
Meta-Analysis
BACKGROUND
In recent decades, increasing longevity (among other factors) has fostered a rise in Parkinson's disease incidence. Although not exhaustively studied in this devastating disease, the impact of sex represents a critical variable in Parkinson's disease as epidemiological and clinical features differ between males and females.
METHODS
To study sex bias in Parkinson's disease, we conducted a systematic review to select sex-labeled transcriptomic data from three relevant brain tissues: the frontal cortex, the striatum, and the substantia nigra. We performed differential expression analysis on each study chosen. Then we summarized the individual differential expression results with three tissue-specific meta-analyses and a global all-tissues meta-analysis. Finally, results from the meta-analysis were functionally characterized using different functional profiling approaches.
RESULTS
The tissue-specific meta-analyses linked Parkinson's disease to the enhanced expression of MED31 in the female frontal cortex and the dysregulation of 237 genes in the substantia nigra. The global meta-analysis detected 15 genes with sex-differential patterns in Parkinson's disease, which participate in mitochondrial function, oxidative stress, neuronal degeneration, and cell death. Furthermore, functional analyses identified pathways, protein-protein interaction networks, and transcription factors that differed by sex. While male patients exhibited changes in oxidative stress based on metal ions, inflammation, and angiogenesis, female patients exhibited dysfunctions in mitochondrial and lysosomal activity, antigen processing and presentation functions, and glutamic and purine metabolism. All results generated during this study are readily available by accessing an open web resource ( http://bioinfo.cipf.es/metafun-pd/ ) for consultation and reuse in further studies.
CONCLUSIONS
Our in silico approach has highlighted sex-based differential mechanisms in typical Parkinson Disease hallmarks (inflammation, mitochondrial dysfunction, and oxidative stress). Additionally, we have identified specific genes and transcription factors for male and female Parkinson Disease patients that represent potential candidates as biomarkers to diagnosis.
Topics: Humans; Male; Female; Parkinson Disease; Transcriptome; Substantia Nigra; Inflammation; Transcription Factors; Mediator Complex
PubMed: 36414996
DOI: 10.1186/s13293-022-00477-5 -
CNS Neuroscience & Therapeutics Feb 2024Several studies have reported iron accumulation in the basal ganglia to be associated with the development of Parkinson's Disease (PD). Recently, a few trials have... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Several studies have reported iron accumulation in the basal ganglia to be associated with the development of Parkinson's Disease (PD). Recently, a few trials have examined the efficacy of using the iron-chelating agent Deferiprone (DFP) for patients with PD. We conducted this meta-analysis to summarize and synthesize evidence from published randomized controlled trials about the efficacy of DFP for PD patients.
METHODS
A comprehensive literature search of four electronic databases was performed, spanning until February 2023. Relevant RCTs were selected, and their data were extracted and analyzed using the RevMan software. The primary outcome was the change in the Unified Parkinson's Disease Rating Scale (UPDRS-III).
RESULTS
Three RCTs with 431 patients were included in this analysis. DFP did not significantly improve UPDRS-III score compared to placebo (Standardized mean difference -0.06, 95% CI [-0.69, 0.58], low certainty evidence). However, it significantly reduced iron accumulation in the substantia nigra, putamen, and caudate as measured by T2*-weighted MRI (with high certainty evidence).
CONCLUSION
Current evidence does not support the use of DFP in PD patients. Future disease-modification trials with better population selection, adjustment for concomitant medications, and long-term follow up are recommended.
Topics: Humans; Deferiprone; Parkinson Disease; Iron Chelating Agents; Iron; Substantia Nigra
PubMed: 38334258
DOI: 10.1111/cns.14607 -
Neuroscience and Biobehavioral Reviews Jun 2024Dopamine's role in addiction has been extensively studied, revealing disruptions in its functioning throughout all addiction stages. Neuromelanin in the substantia nigra... (Meta-Analysis)
Meta-Analysis Review
Dopamine's role in addiction has been extensively studied, revealing disruptions in its functioning throughout all addiction stages. Neuromelanin in the substantia nigra (SN) may reflect dopamine auto-oxidation, and can be quantified using neuromelaninsensitive magnetic resonance imaging (neuromelanin-MRI) in a non-invasive manner.In this pre-registered systematic review, we assess the current body of evidence related to neuromelanin levels in substance use disorders, using both post-mortem and MRI examinations. The systematic search identified 10 relevant articles, primarily focusing on the substantia nigra. An early-stage meta-analysis (n = 6) revealed varied observations ranging from standardized mean differences of -3.55 to +0.62, with a pooled estimate of -0.44 (95 % CI = -1.52, 0.65), but there was insufficient power to detect differences in neuromelanin content among individuals with substance use disorders. Our gap analysis highlights the lack of sufficient replication studies, with existing studies lacking the power to detect a true difference, and a complete lack of neuromelanin studies on certain substances of clinical interest. We provide recommendations for future studies of dopaminergic neurobiology in addictions and related psychiatric comorbidities.
Topics: Humans; Melanins; Substance-Related Disorders; Substantia Nigra; Magnetic Resonance Imaging
PubMed: 38678736
DOI: 10.1016/j.neubiorev.2024.105690 -
Journal of Parkinson's Disease 2022Essential tremor (ET) and the tremor of Parkinson's disease (PD) are the most common tremors encountered in clinical practice. Especially in early disease stages,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Essential tremor (ET) and the tremor of Parkinson's disease (PD) are the most common tremors encountered in clinical practice. Especially in early disease stages, discrimination between the tremors of ET and PD can be challenging.
OBJECTIVE
The aim of this study was to evaluate the diagnostic accuracy of transcranial sonography (TCS) of the substantia nigra echogenicity for differential diagnosis of PD versus ET.
METHODS
A systematic PubMed search identified 512 studies. Sensitivity and specificity of substantia nigra hyperechogenicity was estimated. Data synthesis was carried applying a random effects bivariate binomial model. To assess study quality and risk of bias, the QUADAS-2 tool was used.
RESULTS
Eighteen studies were suitable for analysis including 1,264 PD and 824 ET patients. The meta analysis showed a pooled sensitivity and specificity for TCS in the differential diagnosis of PD versus ET of 84.6% (95% CI, 79.4-88.6%) and 83.9% (95% CI, 78.4-88.2%), respectively. Furthermore, we found nearly similar results in sensitivity and specificity comparing TCS and DaTSCAN in a subgroup-analysis of three studies using both diagnostic tools including 107 patients with PD and 62 patients with ET. The QUADAS-2 toolbox revealed a high risk of bias regarding the methodological quality of patient selection.
CONCLUSION
Substantia nigra hyperechogenicity yield high diagnostic accuracy for the discrimination of PD from ET. TCS is a low cost, widely available, non-invasive marker without radiation Therefore, a diagnostic algorithm based on presence or absence of substantia nigra hyperechogenicity is highly warranted.
Topics: Essential Tremor; Humans; Parkinson Disease; Substantia Nigra; Tremor; Ultrasonography; Ultrasonography, Doppler, Transcranial
PubMed: 35180133
DOI: 10.3233/JPD-213012 -
Stereotactic and Functional Neurosurgery 2020Direct targeting methods for stereotactic neurosurgery in the treatment of essential tremor have been the subject of active research over the past decade but have not... (Meta-Analysis)
Meta-Analysis
Direct targeting methods for stereotactic neurosurgery in the treatment of essential tremor have been the subject of active research over the past decade but have not yet been systematically reviewed. We present a clinically oriented topic review based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses Group guidelines. Our focus is studies using advanced magnetic resonance imaging (MRI) techniques (ultrahigh-field structural MRI, diffusion-weighted imaging, diffusion-tensor tractography, and functional MRI) for patient specific, in vivo identification of the ventral intermediate nucleus and the dentato-rubro-thalamic tract.
Topics: Cerebellar Nuclei; Deep Brain Stimulation; Diffusion Tensor Imaging; Essential Tremor; Female; Humans; Magnetic Resonance Imaging; Male; Neural Pathways; Red Nucleus; Stereotaxic Techniques; Thalamus
PubMed: 32403112
DOI: 10.1159/000507030 -
Neurosurgical Review Apr 2021Brainstem hemangioblastomas are benign, highly vascular tumors located in the mesencephalon, pons, and medulla oblongata. Although surgical resection is currently... (Meta-Analysis)
Meta-Analysis
Brainstem hemangioblastomas are benign, highly vascular tumors located in the mesencephalon, pons, and medulla oblongata. Although surgical resection is currently considered the main therapeutic option for symptomatic lesions, evidence supporting the application of microsurgery has not been systematically assessed. This meta-analysis aims to evaluate the safety and efficacy of surgical treatment for brainstem hemangioblastomas. A comprehensive search of the PubMed, Embase, and Web of Science databases was performed to identify all English language publications reporting the outcomes of surgical treatment for brainstem hemangioblastomas. Studies from January 1990 to July 2019 with ≥ 10 cases were included. We analyzed the surgical outcomes, including gross total resection, mortality, neurological morbidity, and functional outcome according to the McCormick Scale or Karnofsky Performance Scale. Thirteen studies with 473 cases were included. The pooled proportion of gross total resection was 98% (95% confidence interval (CI), 94-100%). Overall mortality and neurological morbidity were 4 (95% CI, 2-6%) and 13% (95% CI, 7-20%), respectively. Favorable functional outcomes at the last follow-up were achieved in 85% (95% CI, 78-92%) of all patients. Improved or stable functional outcomes at long-term follow-up were achieved in 94% (95% CI, 89-97%) of patients. This meta-analysis revealed that surgical treatment for brainstem hemangioblastomas is technically feasible and effective with lasting patient benefits and cure.
Topics: Adult; Brain Stem Neoplasms; Female; Hemangioblastoma; Humans; Karnofsky Performance Status; Male; Microsurgery; Middle Aged; Neurosurgical Procedures; Observational Studies as Topic; Retrospective Studies; Treatment Outcome
PubMed: 32356022
DOI: 10.1007/s10143-020-01305-3