S. Brockstedt

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The purpose of the study was to explore the possibilities of using diffusion tensor imaging (DTI) and tractography (DTT) for the differential diagnosis and monitoring of disease progression in idiopathic Parkinson’s disease (IPD), compared with the atypical parkinsonian disorders multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). A(More)
OBJECTIVE This study aimed to explore the potential of in vivo q-space imaging in the differentiation between different cerebral water components. MATERIALS AND METHODS Diffusion-weighted imaging was performed in six directions with 32 equally spaced q values and a maximum b value of 6600 s/mm(2). The shape of the signal-attenuation curve and the(More)
OBJECTIVE Perfusion-related parameters obtained by intravoxel incoherent motion (IVIM) MR imaging (MRI) were compared with cerebral blood volume and flow (CBV and CBF), retrieved by dynamic susceptibility-contrast (DSC) MRI. MATERIAL AND METHODS Twenty-eight volunteers (average age 68.5 years) were investigated. Spin-echo echo-planar imaging with(More)
The formalin-fixed brain of a patient with clinically diagnosed frontotemporal dementia (FTD) was examined post-mortem using magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) at 3.0 T. Frontotemporal atrophy as well as bilateral frontal white matter abnormalities were seen. The white matter changes were slightly more extensive on DTI than(More)
In this work, we have evaluated the performance of a diffusion-sensitive fast spin-echo (FSE) pulse sequence. The proposed pulse sequence utilises velocity-compensating diffusion-encoding gradients and includes the collection of navigator echoes. Spoiler gradients were inserted in the slice-selecting direction to minimise effects from stimulated echoes.(More)
We present the first in vivo application of the filter-exchange imaging protocol for diffusion MRI. The protocol allows noninvasive mapping of the rate of water exchange between microenvironments with different self-diffusivities, such as the intracellular and extracellular spaces in tissue. Since diffusional water exchange across the cell membrane is a(More)
The accuracy of q-space measurements was evaluated at a 3.0-T clinical magnetic resonance imaging (MRI) scanner, as compared with a 4.7-T nuclear magnetic resonance (NMR) spectrometer. Measurements were performed using a stimulated-echo pulse-sequence on n-decane as well as on polyethylene glycol (PEG) mixed with different concentrations of water, in order(More)
Specific parameters of the neuronal tissue microstructure, such as axonal diameters, membrane permeability and intracellular water fractions are assessable using diffusion MRI. These parameters are commonly estimated using analytical models, which may introduce bias in the estimated parameters due to the approximations made when deriving the models. As an(More)
The aim of this study was to investigate the diffusion time dependence of signal-versus-b curves obtained from diffusion-weighted magnetic resonance imaging (DW-MRI) of sub-acute ischaemic lesions in stroke patients. In this case series study, 16 patients with sub-acute ischaemic stroke were examined with DW-MRI using two different diffusion times (60 and(More)
PURPOSE To evaluate artifact sizes at 3 T compared to at 1.5 T, and to evaluate the influence of scanning parameters with respect to artifact size on a 3-T magnetic resonance imaging (MRI) system. MATERIALS AND METHODS Two aneurysm clips and five shunt valves were imaged in a water phantom at 1.5 and 3 T. At 3 T the influence of bandwidth (spin echo (SE)(More)