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Magnetic resonance diffusion tensor imaging (DTI) provides information about fiber local directions in brain white matter. This paper addresses inference of the connectivity induced by fascicles made up of numerous fibers from such diffusion data. The usual fascicle tracking idea, which consists of following locally the direction of highest diffusion, is(More)
BACKGROUND Damage to white matter tracts, resulting in "cerebral disconnection," may underlie age-related cognitive decline. METHODS Using diffusion tensor MRI (DTI) to investigate white matter damage, and magnetic resonance spectroscopy (MRS) to look at its underlying pathologic basis, the authors investigated the relationship between white matter(More)
OBJECTIVE To determine whether diffusion tensor imaging (DTI) can detect structural changes in normal-appearing white matter, and to distinguish between plaques of different pathologic severity, in patients with MS. BACKGROUND Conventional MRI detects lesions sensitively in MS but has limited pathologic specificity. The diffusion of water molecules in(More)
Biexponential diffusion decay is demonstrated in the human brain in vivo using b factors up to 4000 sec mm(-2). Fitting of the signal decay data yields values for the slow and fast diffusion components and volume fractions in agreement with previous studies in rat and human brain. In addition, differences in the fitted parameters are demonstrated in the(More)
Diffusion-based tractography enables the graphical reconstruction of the white matter pathways in the brain and spinal cord of living humans. This technique has many potential clinical applications, including the investigation of stroke, multiple sclerosis, epilepsy, neurodegenerative diseases, and spinal cord disorders, and it enables hypotheses to be(More)
OBJECTIVES Diffusion tensor imaging (DTI), a technique capable of examining water diffusion in different tissues and the organisation of white matter tracts, was used to investigate the neuropathology of the corpus callosum in vivo in patients with schizophrenia. METHODS Diffusion tensor imaging was performed in 20 schizophrenic patients and 25 healthy(More)
Diffusion tensor imaging (DTI) fully characterises water molecule mobility in vivo, allowing an exploration of fibre tract integrity and orientation in the human brain. Using DTI this study demonstrates reduced fibre coherence (anisotropy) associated with cerebral infarction and in the corticospinal tract remote from the lesion, in five patients 2 to 6(More)
The idea that the initiating event in the formation of all new multiple sclerosis lesions is a focal blood-brain barrier (BBB) leakage associated with perivascular inflammation has been challenged recently by the observation of subtle abnormalities in some quantitative magnetic resonance (MR) parameters (including the magnetization transfer ratio) prior to(More)
A range of liquids suitable as quality control test objects for measuring the accuracy of clinical MRI diffusion sequences (both apparent diffusion coefficient and tensor) has been identified and characterized. The self-diffusion coefficients for 15 liquids (3 cyclic alkanes: cyclohexane to cyclooctane, 9 n-alkanes: n-octane to n-hexadecane, and 3(More)
Diffusion tensor imaging (DTI) studies have demonstrated white matter (WM) abnormalities in tracts involved in emotion processing in autism spectrum disorder (ASD), but little is known regarding the nature and distribution of WM anomalies in relation to ASD trait severity in adults. Increasing evidence suggests that ASD occurs at the extreme of a(More)