Sökning: "flow imaging"
Visar resultat 1 - 5 av 351 avhandlingar innehållade orden flow imaging.
1. Blood flow assessment in cerebral arteries with 4D flow magnetic resonance imaging : an automatic atlas-based approach
Sammanfattning : Background: Disturbed blood flow to the brain has been associated with several neurological diseases, from stroke and vascular diseases to Alzheimer’s and cognitive decline. To determine the cerebral arterial blood flow distribution, measurements are needed in both distal and proximal arteries. LÄS MER
2. Laser Doppler Flowmetry and Imaging: Methodological Studies
Sammanfattning : Laser Doppler flowmetry (LDF) and laser Doppler imaging (LDI) are modern methods for non-invasive and continuous assessment of skin blood flow. The techniques are based on the phenomenon that monochromatic light transilluminating a perfused tissue is spectrally broadened owing to scattering by moving blood cells. LÄS MER
3. Non-invasive imaging for improved cardiovascular diagnostics : Shear wave elastography, relative pressure estimation, and tomographic reconstruction
Sammanfattning : Throughout the last century, medical imaging has come to revolutionise the way we diagnose disease, and is today an indispensable part of virtually any clinical practice. In cardiovascular care imaging is extensively utilised, and the development of novel techniques promises refined diagnostic abilities: ultrasound elastography allows for constitutive tissue assessment, 4D flow magnetic resonance imaging (MRI) enables full-field flow mapping, and micro-Computed Tomography (CT) permits high-resolution imaging at pre-clinical level. LÄS MER
4. Cerebral blood flow distribution, collateral function and pulsatility in healthy and in patients with symptomatic carotid stenosis : a magnetic resonance imaging approach
Sammanfattning : Background: For the detection and treatment of early cerebral vascular disease it is of paramount importance to first understand the normal physiology of the cerebral vasculature, and subsequently, to understand how and when pathology can develop from that. This is especially important as the population above 65 years of age is increasing and aging itself is an established risk factor for the development of cerebral vascular disease. LÄS MER
5. NMR Imaging of Flow and Perfusion using Hyperpolarized Nuclei: Theoretical Considerations and Application to Experimental Models
Sammanfattning : In the studies presented in this thesis, hyperpolarized tracers have been used for the study of macroscopic flow and capillary perfusion with magnetic resonance imaging. The feasibility of performing vascular studies using echo-planar imaging (EPI) and hyperpolarized 129Xe was investigated using xenon dissolved in ethanol prior to injection into a flow phantom. LÄS MER