Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Language task-based functional MRI (fMRI) is increasingly used for presurgical planning in patients with brain lesions. Different paradigms elicit activations of different components of the language network. The aim of this study is to optimize fMRI clinical usage by comparing the effectiveness of three language tasks for language lateralization and localization in a large group of patients with brain lesions. ⋯ SC task consistently produced large activations within the dominant hemisphere and was more effective for lateralizing language within the posterior language areas. The low degree of spatial overlap among the tasks strongly supports the practice of using a battery of tasks to help the surgeon to avoid eloquent language areas.
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Graph theory analysis of brain connectivity data is a promising tool for studying the function of the healthy and diseased brain. The consistency of resting-state functional MRI (rsfMRI) connectivity measures across multiple scanner types is an important factor in designing multi-institutional research studies and has important implications for the potential use of this technique in a heterogeneous clinical setting. We sought to quantitatively study the interscanner variability of rsfMRI graph theory metrics obtained from healthy volunteers scanned on three different scanner platforms. ⋯ There was high consistency of graph theory metrics of rsfMRI connectivity networks among healthy volunteers scanned on three different generation 3T MRI scanners.
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Infarct core assessment on presentation is important to evaluate salvageable tissue to select patients for thrombectomy. Our study aims to evaluate the correlation between infarct core volume measured by computed tomography (CT) perfusion (CTP) and magnetic resonance diffusion-weighted imaging (MR-DWI) in patients with acute large-vessel occlusion. ⋯ CTP provides a good estimation of the core infarct volume. It performs well within the clinically relevant thresholds for patient selection for thrombectomy.
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Acute multi-territory, embolic cerebral infarctions are often associated with serious underlying clinical conditions including the presence of highly "active" emboligenic sources causing that in turn may result in high early recurrence rates. Prompt diagnosis, risk stratification, and treatment are substantial for the prevention of subsequent embolization that would result in further clinical deterioration. ⋯ The presence and burden of MES, especially in multiple intracranial arteries, is clearly associated with an increased risk of symptomatic, recurrent embolization, and thus can justify a more aggressive treatment approach (clopidogrel load followed by dual antiplatelet therapy or alternatively therapeutic dose of low-molecular-weight heparin). In this narrative review, we discuss the most important causes of multi-territory embolic ischemic strokes and also underscore the utility of TCD as a noninvasive tool for the diagnosis, risk stratification, and treatment.
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Posttraumatic stress disorder (PTSD) is a heterogeneous condition associated with a range of brain imaging abnormalities. Early life stress (ELS) contributes to this heterogeneity, but we do not know how a history of ELS influences traditionally defined brain signatures of PTSD. Here, we used a novel machine learning method - evolving partitions to improve classification (EPIC) - to identify shared and unique structural neuroimaging markers of ELS and PTSD in 97 combat-exposed military veterans. ⋯ EPIC revealed unique patterns of features that distinguished PTSD and ELS in this sample of combat-exposed military veterans, which may represent distinct biotypes of stress-related neuropathology.