Journal of neuroimaging : official journal of the American Society of Neuroimaging
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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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Cervical spine symptoms are a major cause of visits to general or spinal orthopedic surgeons or even primary care physicians. Although in this era the imaging studies can precisely rule out or diagnose pathologies in the spine, all of these studies have limitations. Computerized tomography (CT) scan consists of radiation exposure to the patients and it should be done with caution. Magnetic resonance imaging (MRI) is a highly effective imaging tool, but in many countries it is still costly. The goal of our study was to determine whether a simple clinical test can help the clinician to identify the patients who need to be sent for these imaging studies. ⋯ This paper demonstrate that patients with positive Spurling test have probable nerve root pressure and should be sent for further imaging studies. In patients with negative Spurling test, the possibility of nerve root pressure is less likely.
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The human visual system responds asymmetrically to visual motion stimuli in opposite directions due to the involvement of the same brain areas but different operating processes. The expansion mode is thought to invoke a vigilance mechanism, whereas the contraction mode does not. ⋯ These findings show that detect spatiotemporal differences between expansion and contraction modes can be readily detected using time-flow charts. Moreover, delay interactions could be insensitive to object motion away from the observer.
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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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To determine acute intracranial hydrodynamic changes after subarachnoid hemorrhage (SAH) via phase-contrast MRI (PC-MRI) analysis of the CSF stroke volume in the aqueduct (SVaq) and the foramen magnum (SVfm). ⋯ SAH led to changes in cerebrospinal fluid hydrodynamics in the majority of patients. Acute HC was communicating in most cases, even when there was intraventricular bleeding. In the late phase, all chronic HC were communicating and did not display aqueductal stenosis.