Sökning: "cerebral blood volume"

Visar resultat 1 - 5 av 43 avhandlingar innehållade orden cerebral blood volume.

  1. 1. Cerebral blood flow distribution, collateral function and pulsatility in healthy and in patients with symptomatic carotid stenosis  : a magnetic resonance imaging approach

    Författare :Laleh Zarrinkoob; Jan Malm; Anders Eklund; Khalid Ambarki; Sepideh Amin-Hanjani; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Aging; Arterial pulsatility; Carotid stenosis; Cerebral arteries; Cerebral blood flow; Cerebral collateral blood flow; Circle of Willis; Phase contrast magnetic resonance imaging;

    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

  2. 2. Blood flow assessment in cerebral arteries with 4D flow magnetic resonance imaging : an automatic atlas-based approach

    Författare :Tora Dunås; Anders Eklund; Anders Wåhlin; Jan Malm; Einar Heiberg; Umeå universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Circle of Willis; 4D flow MRI; Cerebral arteries; Vascular disease; Stroke; Automatic labeling; Probabilistic atlas; Cerebral blood flow; Neuroimaging; Magnetic Resonance Imaging;

    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

  3. 3. Cerebral blood flow and intracranial pulsatility studied with MRI : measurement, physiological and pathophysiological aspects

    Författare :Anders Wåhlin; Anders Eklund; Jan Malm; Richard Birgander; William G Bradley; Umeå universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Arterial Pulsatility; cerebrospinal fluid; cerebral blood flow; venous flow; intracranial pressure; pulse pressure; dementia; hippocampus; multiple sclerosis; magnetic resonance imaging; radiofysik; radiation physics;

    Sammanfattning : During each cardiac cycle pulsatile arterial blood inflates the vascular bed of the brain, forcing cerebrospinal fluid (CSF) and venous blood out of the cranium. Excessive arterial pulsatility may be part of a harmful mechanism causing cognitive decline among elderly. LÄS MER

  4. 4. MRI Perfusion Measurements using Magnetic Susceptibility Effects: : Calibration Approaches and Contrast Agent Quantification

    Författare :Emelie Lind; Lund Medicinsk strålningsfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; contrast agent; cerebral blood flow; cerebral blood volume; mean transit time; perfusion; dynamic susceptibility contrast MRI; magnetic susceptibility;

    Sammanfattning : Exchange of oxygen and nutrients between blood and tissue occurs at the capillary level of the blood system. The blood volume flow rate in the capillaries is often referred to as perfusion, and knowledge about perfusion provides important information about the function and viability of the tissue, for example, in patients with ischaemic stroke, cancer, and neurodegenerative diseases. LÄS MER

  5. 5. Optimisation and Validation of Dynamic Susceptibility Contrast MRI Perfusion Measurements

    Författare :Linda Knutsson; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Nukleärmedicin; radiobiologi; Nuclear medicine; radiobiology; radiologi; tomografi; medicinsk instrumentering; tomography; medical instrumentation; Clinical physics; cerebral blood volume; mean transit time; cerebral blood flow; perfusion; dynamic susceptibility contrast MRI arterial input function; Klinisk fysiologi; radiology;

    Sammanfattning : The studies presented in this thesis concern the optimisation and evaluation of the dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) technique for the assessment of perfusion-related parameters of the brain, such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT). Several methodological factors influence these measurements, for example, contrast-agent administration, arterial input function (AIF) registration, choice of deconvolution algorithm and the choice of pulse-sequence parameters. LÄS MER