Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Comparative Study
Giant Cerebral Aneurysms: Comparing CTA, MRA, and Digital Subtraction Angiography Assessments.
Comprehensive imaging characterization of the morphology and luminal patency of cerebral aneurysms are cornerstones of their successful treatment and subsequent appropriate management. Giant cerebral aneurysms (GCAs), a distinct subgroup of aneurysms, are defined by large size (≥ 25 mm in greatest diameter), complex blood flow dynamics, and a high risk of rupture. The purpose of this study is to explore compare multiple imaging modalities in the assessment of GCAs. ⋯ CTA, 3D TOFMRA, and CEMRA are equivalent in the delineation of size of GCAs. Nevertheless, 3D TOFMRA and CEMRA seem to be inferior to CTA in demonstrating luminal size/patency, likely because of the signal loss resulting from the presence of intraluminal thrombus and flow turbulence. Moreover, CTA is superior to DSA in determining lumen patency in GCAs, probably due to CTA's multipass-related luminal enhancement while DSA general fills the lesion via the first pass of enhancement or soon thereafter. In addition, CTA may also better demonstrate intraluminal thrombus, adjacent anatomical structures, and calcified rims.
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The process of myelination starts in utero around 20 weeks of gestation and continues through adulthood. We first set out to characterize the maturation of the tract-specific myelin content in healthy subjects from childhood (7-12 years) into adulthood (18-32 years). Second, we apply the resulting development graph to children with childhood absence epilepsy (CAE), a pediatric epilepsy that was previously characterized by changes in myelin content. ⋯ These results indicate that CAE is associated with widespread neurodevelopmental myelin differences.
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Imaging-based selection of stroke patients for endovascular thrombectomy (EVT) remains an ongoing challenge. Our aim was to determine the value of a combined parameter of ischemic core volume (ICV) and the relative degree of cerebral blood flow in the penumbra for morphologic and clinical outcome prediction. ⋯ In EVT-treated stroke patients, pw-ICV outperforms the more commonly used ICV in the prediction of morphological and functional outcome.
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Geometric distortions resulting from large pose changes reduce the accuracy of motion measurements and interfere with the ability to generate artifact-free information. Our goal is to develop an algorithm and pulse sequence to enable motion-compensated, geometric distortion compensated diffusion-weighted MRI, and to evaluate its efficacy in correcting for the field inhomogeneity and position changes, induced by large and frequent head motions. ⋯ Dual-echo acquisitions with blip-reversed phase encoding can be used to generate slice-level distortion-free images, which is critical for motion-robust slice to volume registration. The distortion corrected images not only result in better motion estimates, but they also enable a more accurate final diffusion image reconstruction.
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Numerous sex-specific differences in multiple sclerosis (MS) susceptibility, disease manifestation, disability progression, inflammation, and neurodegeneration have been previously reported. Previous magnetic resonance imaging (MRI) studies have shown structural differences between female and male MS brain volumes. To determine sex-specific global and tissue-specific brain volume throughout the MS life span in a real-world large MRI database. ⋯ There are sex-specific differences in the LVV and GMV over the MS life span.