Journal of neuroimaging : official journal of the American Society of Neuroimaging
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We investigated a simple imaging sign for Alzheimer's disease (AD), using diffusion tensor imaging (DTI). We hypothesized that a reduction in fractional anisotropy (FA) in the fornix could be utilized as an imaging sign. ⋯ The fornix sign is a promising predictive imaging sign of AD.
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Intravascular ultrasound (IVUS) has provided invaluable real-time information during carotid artery stenting (CAS). We present a case of IVUS-guided thrombus extraction during CAS. A 46-year-old man underwent an urgent right CAS under proximal flow reversal for embolic protection for a hemodynamically significant symptomatic near-occlusion of the internal carotid artery. ⋯ Ultimately, the thrombus was removed with the use of a multipurpose-angled catheter under IVUS guidance. The artery reconstituted almost completely after stent placement, and the patient's condition improved significantly. IVUS identification of intraluminal thrombus allowed additional maneuvers to be performed to prevent distal embolization and postprocedure stroke.
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Multicenter Study
Preliminary MRI quality assessment and device acceptance guidelines for a multicenter bioclinical study: the GO Glioblastoma Project.
It is a major challenge to guarantee homogeneous acquisition during a prospective multicenter magnetic resonance imaging (MRI) study that makes use of different devices. The goal of the multicenter Grand Ouest Glioblastoma Project (GOGP) was to correlate MRI quantitative parameters with biological markers extracted from image-guided biopsies. Therefore, it was essential to ensure spatial coherence of the parameters as well as the signal intensity and homogeneity. ⋯ A fourth test-object was used to assess T1 accuracy. Although geometry-related parameters, signal-to-noise ratio, uniformity, and T1 measurements varied slightly depending on the different devices, they nevertheless remained within the recommendations and expectations of the multicenter project. This kind of quality control procedure should be undertaken as a prerequisite to any multicenter clinical project involving quantitative MRI and comparison of data acquisitions with quantitative biological image-guided biopsies.
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In multiple sclerosis (MS), the presence of lesions and normal-appearing white matter damage may affect the reliability of diffusion tensor (DT) magnetic resonance imaging (MRI)-based tractography. We compared the performance of an individual-based method for corpus callosum (CC) fiber tracking in MS with those of two atlas-based methods. ⋯ CC DT tractography using an individual-based method is more sensitive than the atlas-based ones to tract-specific alterations related to MS disability. An atlas-based method with nonlinear registration can be a valid alternative when an automated postprocessing is warranted, such as in the case of high volumes of data.
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Perfusion-CT (PCT) of the brain is a rapidly evolving imaging technique used to assess blood supply to the brain parenchyma. PCT is readily available at most imaging centers, resulting in steadily increasing use of this imaging technique. ⋯ Therefore, it is important for the radiologist to recognize altered perfusion patterns observed in diseases other than typical ischemic stroke. The goal of this article is to show the perfusion maps and review the perfusion patterns observed in some subtypes of atypical stroke and in neurological entities other than stroke, so that they are recognized and not confused with the PCT patterns observed in patients with typical ischemic stroke.