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Visar resultat 1 - 5 av 266 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Movement artifact reduction in laser Doppler blood flowmetry : myocardial perfusion applications

   Författare :MG Daniel Karlsson; Karin Wårdell; Knut Kvernebo; Linköpings universitet; []
   Nyckelord :MEDICINE; MEDICIN;

   Sammanfattning : Laser Doppler perfusion monitoring (LDPM) and imaging (LDPI) enable assessment of tissue microvascular perfusion. The techniques are based on the Doppler broadening of the optical spectrum occurring when coherent laser light is scattered by moving red blood cells (RBC). LÄS MER

3. 2. Optimisation and Validation of Dynamic Susceptibility Contrast MRI Perfusion Measurements

   Författare :Linda Knutsson; Lund Medicinsk strålningsfysik; []
   Nyckelord :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

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

   Författare :Emelie Lind; Lund Medicinsk strålningsfysik; []
   Nyckelord :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. 4. WAVELET NOISE REDUCTION AND VASCULAR WATER TRANSPORT MODELLING : APPLICATIONS TO DIFFUSION AND PERFUSION MRI

   Författare :Adnan Bibic; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; cerebral blood flow; perfusion; diffusion; arterial spin labelling; wavelets; filtering; denoising; blood-brain barrier; permeability; Fysicumarkivet A:2018:Bibic;

   Sammanfattning : Magnetic resonance imaging (MRI) is a powerful medical imaging technique, used to detect and characterise a range of diseases and conditions. It is based on the use of a strong static magnetic field in combination with magnetic field gradients and pulsed radiofrequency electromagnetic fields to visualise various organs and structures in the body according to their morphology or function. LÄS MER

7. 5. Quantitative Tracer Based MRI Perfusion : Potentials and Limitations

   Författare :Arvid Morell; Atle Bjørnerud; Håkan Ahlström; Linda Knutsson; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MRI; Perfusion; Contrast agent; Relaxivity; Radiology; Radiologi;

   Sammanfattning : Tracer based MRI perfusion measurements is a clinically useful tool to assess regional distributions of tissue blood flow and volume. The method may be based on any of the three relaxation mechanisms T1, T1 and T2*, the latter denoted DSC-MRI being the most common. LÄS MER