Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Meta Analysis
A Meta-Analysis of fMRI Activation Differences during Episodic Memory in Alzheimer's Disease and Mild Cognitive Impairment.
Functional MRI (fMRI) has the potential to be used as a tool to detect biomarkers related to classifying Alzheimer's disease (AD) and its prodromal stage, mild cognitive impairment (MCI). Previous meta-analyses suggest that during episodic memory tasks, MCI patients exhibit hyperactivation in the medial temporal lobe (MTL) while AD patients exhibit hypoactivation, compared to healthy older adults (HOAs). However, these previous studies have methodological weaknesses that limit the generalizability of the results. ⋯ Additionally, the HOA sample showed more activation in the right hippocampus compared to the AD sample. The MCI studies showed greater activation in the cerebellum compared to the HOA sample, potentially indicating a compensatory mechanism for verbal encoding. MTL hypoactivation in the AD sample is consistent with previous studies, but more evidence of MCI hyperactivation is needed before considering MTL activation as an early biomarker for the AD disease process.
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During the operation, accurately identifying the boundary of cerebral arteriovenous malformation (AVM) and discriminating between feeding arteries and draining veins is the key to successful surgical treatment of cerebral AVM. We evaluated the application of intraoperative ultrasonography (IOU) combined with intraoperative indocyanine green video-angiography (IOICGA) in the patients with cerebral AVM. ⋯ IOU combined with IOICGA can identify the boundary of AVM, detect deep vessels, and discriminate between feeding arteries and draining veins, reducing operation difficulty, decreasing mortality and disability rate, and increasing the rate of complete excision.
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Isolated and reversible lesion restricted to the splenium of the corpus callosum, known as reversible splenial lesion syndrome, have been reported in patients with infection, high-altitude cerebral edema, seizures, antiepileptic drug withdrawal, or metabolic disturbances. Here, we report a 39-year-old female patient with glufosinate ammonium (GLA) poisoning who presented with confusion and amnesia. ⋯ The lesion was not present on follow-up MR imaging performed 9 months later. We postulate that a GLA-induced excitotoxic mechanism was the cause of this reversible splenial lesion.
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Sophisticated algorithms to infer disease diagnosis, pathology progression and patient outcome are increasingly being developed to analyze brain MRI data. They have been successfully implemented in a variety of diseases and are currently investigated in the field of neuropsychiatric disorders, including autism spectrum disorder (ASD). We aim to test the ability to predict ASD from subtle morphological changes in structural magnetic resonance imaging (sMRI). ⋯ Despite the subtle impact of ASD on brain morphology and a limited cohort size, results from sMRI-based classifiers suggest a consistent network of altered brain regions.
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Diffusion tensor imaging (DTI) tractography reconstruction of white matter pathways can help guide brain tumor resection. However, DTI tracts are complex mathematical objects and the validity of tractography-derived information in clinical settings has yet to be fully established. To address this issue, we initiated the DTI Challenge, an international working group of clinicians and scientists whose goal was to provide standardized evaluation of tractography methods for neurosurgery. The purpose of this empirical study was to evaluate different tractography techniques in the first DTI Challenge workshop. ⋯ The DTI Challenge provides a benchmark for the standardized evaluation of tractography methods on neurosurgical data. This study suggests that there are still limitations to the clinical use of tractography for neurosurgical decision making.