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Fluids and Barriers of the CNS Dec 2023The neurovascular unit (NVU) is a complex structure that facilitates nutrient delivery and metabolic waste clearance, forms the blood-brain barrier (BBB), and supports... (Review)
Review
The neurovascular unit (NVU) is a complex structure that facilitates nutrient delivery and metabolic waste clearance, forms the blood-brain barrier (BBB), and supports fluid homeostasis in the brain. The integrity of NVU subcomponents can be measured in vivo using magnetic resonance imaging (MRI), including quantification of enlarged perivascular spaces (ePVS), BBB permeability, cerebral perfusion and extracellular free water. The breakdown of NVU subparts is individually associated with aging, pathology, and cognition. However, how these subcomponents interact as a system, and how interdependencies are impacted by pathology remains unclear. This systematic scoping review identified 26 studies that investigated the inter-relationships between multiple subcomponents of the NVU in nonclinical and neurodegenerative populations using MRI. A further 112 studies investigated associations between the NVU and white matter hyperintensities (WMH). We identify two putative clusters of NVU interdependencies: a 'vascular' cluster comprising BBB permeability, perfusion and basal ganglia ePVS; and a 'fluid' cluster comprising ePVS, free water and WMH. Emerging evidence suggests that subcomponent coupling within these clusters may be differentially related to aging, neurovascular injury or neurodegenerative pathology.
Topics: Magnetic Resonance Imaging; Brain; Blood-Brain Barrier; Water
PubMed: 38129925
DOI: 10.1186/s12987-023-00499-0 -
Brain and Language Sep 2023We systematically reviewed the literature on neural changes following anomia treatment post-stroke. We conducted electronic searches of CINAHL, Cochrane Trials, Embase,... (Review)
Review
We systematically reviewed the literature on neural changes following anomia treatment post-stroke. We conducted electronic searches of CINAHL, Cochrane Trials, Embase, Ovid MEDLINE, MEDLINE-in-Process and PsycINFO databases; two independent raters assessed all abstracts and full texts. Accepted studies reported original data on adults with post-stroke aphasia, who received behavioural treatment for anomia, and magnetic resonance brain imaging (MRI) pre- and post-treatment. Search results yielded 2481 citations; 33 studies were accepted. Most studies employed functional MRI and the quality of reporting neuroimaging methodology was variable, particularly for pre-processing steps and statistical analyses. The most methodologically robust data were synthesized, focusing on pre- versus post-treatment contrasts. Studies more commonly reported increases (versus decreases) in activation following naming therapy, primarily in the left supramarginal gyrus, and left/bilateral precunei. Our findings highlight the methodological heterogeneity across MRI studies, and the paucity of robust evidence demonstrating direct links between brain and behaviour in anomia rehabilitation.
Topics: Adult; Humans; Anomia; Aphasia; Neuroimaging; Neuronal Plasticity; Stroke
PubMed: 37633250
DOI: 10.1016/j.bandl.2023.105300 -
International Journal of Gynecological... Jul 2023Endometrial carcinoma is the most common gynecological tumor in developed countries. Clinicopathological factors and molecular subtypes are used to stratify the risk of... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Endometrial carcinoma is the most common gynecological tumor in developed countries. Clinicopathological factors and molecular subtypes are used to stratify the risk of recurrence and to tailor adjuvant treatment. The present study aimed to assess the role of radiomics analysis in pre-operatively predicting molecular or clinicopathological prognostic factors in patients with endometrial carcinoma.
METHODS
Literature was searched for publications reporting radiomics analysis in assessing diagnostic performance of MRI for different outcomes. Diagnostic accuracy performance of risk prediction models was pooled using the metandi command in Stata.
RESULTS
A search of MEDLINE (PubMed) resulted in 153 relevant articles. Fifteen articles met the inclusion criteria, for a total of 3608 patients. MRI showed pooled sensitivity and specificity 0.785 and 0.814, respectively, in predicting high-grade endometrial carcinoma, deep myometrial invasion (pooled sensitivity and specificity 0.743 and 0.816, respectively), lymphovascular space invasion (pooled sensitivity and specificity 0.656 and 0.753, respectively), and nodal metastasis (pooled sensitivity and specificity 0.831 and 0.736, respectively).
CONCLUSIONS
Pre-operative MRI-radiomics analyses in patients with endometrial carcinoma is a good predictor of tumor grading, deep myometrial invasion, lymphovascular space invasion, and nodal metastasis.
Topics: Female; Humans; Lymphatic Metastasis; Endometrial Neoplasms; Magnetic Resonance Imaging; Sensitivity and Specificity; Neoplasm Grading; Neoplasm Invasiveness
PubMed: 37094971
DOI: 10.1136/ijgc-2023-004313 -
Brain and Behavior Nov 2023Obstructive sleep apnea (OSA) is a common sleep disorder that causes intermittent hypoxia and sleep fragmentation, leading to attention impairment and other cognitive... (Review)
Review
BACKGROUND AND OBJECTIVE
Obstructive sleep apnea (OSA) is a common sleep disorder that causes intermittent hypoxia and sleep fragmentation, leading to attention impairment and other cognitive deficits. Magnetic resonance imaging (MRI) is a powerful modality that can reveal the structural and functional brain alterations associated with attention impairment in OSA patients. The objective of this systematic review is to identify and synthesize the evidence on MRI biomarkers and neuropsychological assessments of attention deficits in OSA patients.
METHODS
We searched the Scopus and PubMed databases for studies that used MRI to measure biomarkers related to attention alteration in OSA patients and reported qualitative and quantitative data on the association between MRI biomarkers and attention outcomes. We also included studies that found an association between neuropsychological assessments and MRI findings in OSA patients with attention deficits.
RESULTS
We included 19 studies that met our inclusion criteria and extracted the relevant data from each study. We categorized the studies into three groups based on the MRI modality and the cognitive domain they used: structural and diffusion tensor imaging MRI findings, functional, perfusion, and metabolic MRI findings, and neuropsychological assessment findings.
CONCLUSIONS
We found that OSA is associated with structural, functional, and metabolic brain alterations in multiple regions and networks that are involved in attention processing. Treatment with continuous positive airway pressure can partially reverse some of the brain changes and improve cognitive function in some domains and in some studies. This review suggests that MRI techniques and neuropsychological assessments can be useful tools for monitoring the progression and response to treatment of OSA patients.
Topics: Humans; Diffusion Tensor Imaging; Sleep Apnea, Obstructive; Brain; Magnetic Resonance Imaging; Biomarkers; Neuropsychological Tests
PubMed: 37743582
DOI: 10.1002/brb3.3262 -
Frontiers in Neurology 2023Transcranial magnetic stimulation (TMS) is a non-invasive intervention that holds promise for improving cognitive function in individuals with Alzheimer's disease (AD)....
INTRODUCTION
Transcranial magnetic stimulation (TMS) is a non-invasive intervention that holds promise for improving cognitive function in individuals with Alzheimer's disease (AD). However, the effectiveness of this therapy and the optimal TMS parameters has not reached a consensus. The purpose of the meta-analysis was to systematically discern the effectiveness of different components of TMS protocols on cognitive improvement in patients with mild cognitive impairment (MCI) and AD.
METHODS
The meta-analysis was preregistered on Prospero (registration number: CRD42022345482). PubMed, Web of Science, Science Direct, and Cochrane Library databases were used to search, screen and identify eligible studies with the following keywords: Transcranial Magnetic Stimulation OR TMS OR theta burst stimulation AND Alzheimer OR Alzheimers OR Alzheimer's OR mild cognitive impairment OR MCI. Randomized controlled trials (RCTs) of participants with accepted standardized diagnostic criteria were searched by two authors independently. The risk of bias was assessed using an adapted Cochrane Risk of Bias tool. Standardized mean difference (SMD) and 95% confidence interval (CI) were calculated using the random-effects models. Subgroup analyses were performed to investigate the influential factors.
RESULTS
A total of 21 studies and 25 trials were included in this meta-analysis. The findings revealed a significant overall cognition improvement of real stimulation compared with sham stimulation (short-term effects: SMD, 0.91; 95% CI 0.44-1.38; < 0.01; long-lasting effects: SMD, 0.91; 95% CI 0.27-1.55; < 0.01). Subgroup analysis demonstrated that stimulation of the left dorsolateral prefrontal cortex and bilateral cerebellums, as well as moderate frequency stimulation (5 Hz and 10 Hz) on mild and moderate cognitive impairment patients, were more effective than other TMS protocols. However, the additional application of cognitive training showed no significant improvement.
CONCLUSION
Cognitive improvement effect of TMS was demonstrated in MCI and AD patients in both short-term assessment and long-lasting outcomes, and the efficiency of TMS is affected by the stimulation frequency, stimulation site, and participant characteristics. Further RCTs are needed to validate the findings of our subgroup analysis.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022345482, identifier: CRD42022345482.
PubMed: 37528850
DOI: 10.3389/fneur.2023.1209205 -
JAMA Network Open May 2024Noninvasive brain stimulation (NIBS) interventions have been shown to be efficacious in several mental disorders, but the optimal dose stimulation parameters for each... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Noninvasive brain stimulation (NIBS) interventions have been shown to be efficacious in several mental disorders, but the optimal dose stimulation parameters for each disorder are unknown.
OBJECTIVE
To define NIBS dose stimulation parameters associated with the greatest efficacy in symptom improvement across mental disorders.
DATA SOURCES
Studies were drawn from an updated (to April 30, 2023) previous systematic review based on a search of PubMed, OVID, and Web of Knowledge.
STUDY SELECTION
Randomized clinical trials were selected that tested transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) for any mental disorder in adults aged 18 years or older.
DATA EXTRACTION AND SYNTHESIS
Two authors independently extracted the data. A 1-stage dose-response meta-analysis using a random-effects model was performed. Sensitivity analyses were conducted to test robustness of the findings. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.
MAIN OUTCOMES AND MEASURES
The main outcome was the near-maximal effective doses of total pulses received for TMS and total current dose in coulombs for tDCS.
RESULTS
A total of 110 studies with 4820 participants (2659 men [61.4%]; mean [SD] age, 42.3 [8.8] years) were included. The following significant dose-response associations emerged with bell-shaped curves: (1) in schizophrenia, high-frequency (HF) TMS on the left dorsolateral prefrontal cortex (LDLPFC) for negative symptoms (χ2 = 9.35; df = 2; P = .009) and TMS on the left temporoparietal junction for resistant hallucinations (χ2 = 36.52; df = 2; P < .001); (2) in depression, HF-DLPFC TMS (χ2 = 14.49; df = 2; P < .001); (3) in treatment-resistant depression, LDLPFC tDCS (χ2 = 14.56; df = 2; P < .001); and (4) in substance use disorder, LDLPFC tDCS (χ2 = 33.63; df = 2; P < .001). The following significant dose-response associations emerged with plateaued or ascending curves: (1) in depression, low-frequency (LF) TMS on the right DLPFC (RDLPFC) with ascending curve (χ2 = 25.67; df = 2; P = .001); (2) for treatment-resistant depression, LF TMS on the bilateral DLPFC with ascending curve (χ2 = 5.86; df = 2; P = .004); (3) in obsessive-compulsive disorder, LF-RDLPFC TMS with ascending curve (χ2 = 20.65; df = 2; P < .001) and LF TMS on the orbitofrontal cortex with a plateaued curve (χ2 = 15.19; df = 2; P < .001); and (4) in posttraumatic stress disorder, LF-RDLPFC TMS with ascending curve (χ2 = 54.15; df = 2; P < .001). Sensitivity analyses confirmed the main findings.
CONCLUSIONS AND RELEVANCE
The study findings suggest that NIBS yields specific outcomes based on dose parameters across various mental disorders and brain regions. Clinicians should consider these dose parameters when prescribing NIBS. Additional research is needed to prospectively validate the findings in randomized, sham-controlled trials and explore how other parameters contribute to the observed dose-response association.
Topics: Humans; Transcranial Magnetic Stimulation; Transcranial Direct Current Stimulation; Mental Disorders; Adult; Male; Female; Middle Aged; Randomized Controlled Trials as Topic
PubMed: 38776083
DOI: 10.1001/jamanetworkopen.2024.12616 -
Clinical Rehabilitation Oct 2023To examine the effectiveness of electrophysical agents in fibromyalgia. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To examine the effectiveness of electrophysical agents in fibromyalgia.
DATA SOURCES
CINAHL, Cochrane Library, Embase, Medline, PEDro, and Web of Science were searched from their inceptions to March 27, 2023.
METHODS
This study was registered in PROSPERO (CRD42022354326). Methodological quality of included trials was assessed using PEDro scale, and the quality of evidence was determined according to the Grading of Recommendations Assessment, Development, and Evaluation system. The primary outcomes were pain, functional status, and mood.
RESULTS
Fifty-four studies involving 3045 patients with fibromyalgia were eligible for qualitative synthesis and 47 (pain), 31 (functional status), and 26 (mood) for network meta-analysis. The network consistency model revealed that, when compared with true control, transcutaneous electrical nerve stimulation and microcurrent improved pain symptoms ( = 0.006 and = 0.037, respectively); repetitive transcranial magnetic stimulation improved patient functional status ( = 0.018); and microcurrent ( = 0.001), repetitive transcranial magnetic stimulation ( = 0.022), and no treatment ( = 0.038) significantly improved mood after intervention. Surface under the cumulative ranking indicated that microcurrent was most likely to be the best for managing pain and mood (surface under the cumulative ranking: 70% and 100%, respectively); low-level laser therapy for pain and mood (80% and 70%, respectively); and repetitive transcranial magnetic stimulation for improving functional status and mood (80% and 70%, respectively).
CONCLUSION
This review found low to moderate quality evidence that microcurrent, laser therapy, and repetitive transcranial magnetic stimulation are the most effective electrophysical agents for improving at least one outcome in fibromyalgia.
Topics: Humans; Fibromyalgia; Network Meta-Analysis; Transcutaneous Electric Nerve Stimulation; Pain; Pain Management
PubMed: 37082791
DOI: 10.1177/02692155231170450 -
Neuroscience and Biobehavioral Reviews Sep 2023Whether remitted major depressive disorder (rMDD) and MDD present common or distinct neuropathological mechanisms remains unclear. We performed a meta-analysis of... (Meta-Analysis)
Meta-Analysis Review
Common and distinct patterns of task-related neural activation abnormalities in patients with remitted and current major depressive disorder: A systematic review and coordinate-based meta-analysis.
Whether remitted major depressive disorder (rMDD) and MDD present common or distinct neuropathological mechanisms remains unclear. We performed a meta-analysis of task-related whole-brain functional magnetic resonance imaging (fMRI) using anisotropic effect-size signed differential mapping software to compare brain activation between rMDD/MDD patients and healthy controls (HCs). We included 18 rMDD studies (458 patients and 476 HCs) and 120 MDD studies (3746 patients and 3863 HCs). The results showed that MDD and rMDD patients shared increased neural activation in the right temporal pole and right superior temporal gyrus. Several brain regions, including the right middle temporal gyrus, left inferior parietal, prefrontal cortex, left superior frontal gyrus and striatum, differed significantly between MDD and rMDD. Meta-regression analyses revealed that the percentage of females with MDD was positively associated with brain activity in the right lenticular nucleus/putamen. Our results provide valuable insights into the underlying neuropathology of brain dysfunction in MDD, developing more targeted and efficacious treatment and intervention strategies, and more importantly, providing potential neuroimaging targets for the early screening of MDD.
Topics: Female; Humans; Depressive Disorder, Major; Brain; Brain Mapping; Prefrontal Cortex; Temporal Lobe; Magnetic Resonance Imaging
PubMed: 37315658
DOI: 10.1016/j.neubiorev.2023.105284 -
Alternative Therapies in Health and... Nov 2023Leukemia is the most prevalent cancer among children and adolescents. This study investigated the potential association between exposure to magnetic fields and the risk... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Leukemia is the most prevalent cancer among children and adolescents. This study investigated the potential association between exposure to magnetic fields and the risk of pediatric leukemia.
METHODS
We conducted a comprehensive search of electronic databases, including Scopus, EMBASE, Cochrane, Web of Science, and Medline, up to December 15, 2022, to identify relevant studies examining the link between childhood leukemia and magnetic field exposure.
RESULTS
The first meta-analysis revealed a statistically significant inverse association between pediatric leukemia and magnetic field strengths ranging from 0.4 μT to 0.2 μT, suggesting a reduced risk associated with this range. The second meta-analysis focused on wiring configuration codes and observed a potential link between residential magnetic field exposure and childhood leukemia. Pooled relative risk estimates were 1.52 (95% CI = 1.05-2.04, P = .021) and 1.58 (95% CI = 1.15-2.23, P = .006) for exposure to 24-hour magnetic field measurements, suggesting a possible causal relationship. In the third meta-analysis, the odds ratios for the exposure groups of 0.1 to 0.2 μT, 0.2 to 0.3 μT, 0.3 to 0.4 μT, and 0.4 μT above 0.2 μT were 1.09 (95% confidence interval = 0.82 to 1.43 μT), 1.14 (95% confidence interval = 0.68 to 1.92 μT), and 1.45 (95% confidence interval = 0.87 to 2.37 μT), respectively. In contrast to the findings of the three meta-analyses, there was no evidence of a statistically significant connection between exposure to 0.2 μT and the risk of juvenile leukemia. A further result showed no discernible difference between the two groups of children who lived less than 100 meters from the source of magnetic fields and those who lived closer (OR = 1.33; 95% CI = 0.98-1.73 μT).
CONCLUSIONS
The collective results of three meta-analyses, encompassing magnetic field strengths ranging from 0.1 μT to 2.38 μT, underscore a statistically significant association between the intensity of magnetic fields and the occurrence of childhood leukemia. However, one specific analysis concluded that no apparent relationship exists between exposure to 0.1 μT and an elevated risk of leukemia development in children.
Topics: Adolescent; Child; Humans; Electromagnetic Fields; Leukemia; Magnetic Fields; Neoplasms; Electromagnetic Radiation; Environmental Exposure; Case-Control Studies
PubMed: 37678874
DOI: No ID Found -
Neuroscience and Biobehavioral Reviews Apr 2024The imaging-based method of brainAGE aims to characterize an individual's vulnerability to age-related brain changes. The present study systematically reviewed brainAGE... (Review)
Review
The imaging-based method of brainAGE aims to characterize an individual's vulnerability to age-related brain changes. The present study systematically reviewed brainAGE findings in neuropsychiatric conditions and discussed the potential of brainAGE as a marker for biological age. A systematic PubMed search (from inception to March 6th, 2023) identified 273 articles. The 30 included studies compared brainAGE between neuropsychiatric and healthy groups (n≥50). We presented results qualitatively and adapted a bias risk assessment questionnaire. The imaging modalities, design, and input features varied considerably between studies. While the studies found higher brainAGE in neuropsychiatric conditions (11 mild cognitive impairment/ dementia, 11 schizophrenia spectrum/ other psychotic and bipolar disorder, six depression/ anxiety, two multiple groups), the associations with clinical characteristics were mixed. While brainAGE is sensitive to group differences, limitations include the lack of diverse training samples, multi-modal studies, and external validation. Only a few studies obtained longitudinal data, and all have used algorithms built solely to predict chronological age. These limitations impede the validity of brainAGE as a biological age marker.
Topics: Humans; Brain; Schizophrenia; Bipolar Disorder; Cognitive Dysfunction; Magnetic Resonance Imaging
PubMed: 38354871
DOI: 10.1016/j.neubiorev.2024.105581