Search for dissertations about: "bolus tracking"

Showing result 1 - 5 of 6 swedish dissertations containing the words bolus tracking.

2. 1. Nuclear magnetic resonance and microcirculation: The influence of pulsatile brain-tissue motion on measurements of intravoxel incoherent motion and assessment of haemodynamics using exo- and endogenous tracers

   Author : Ronnie Wirestam; Lund Medicinsk strålningsfysik; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; diagnostic radiology; cortical activation; diffusion; tumor; tumour; ischemic stroke; ischaemic stroke; tracer kinetics; bolus tracking; phase mapping; brain motion; intracranial dynamics; blood flow; haemodynamics; vascularity; MRS; perfusion; MRI; magnetic resonance; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering;

   Abstract : In this project, the potential of magnetic resonance (MR) imaging and spectroscopy in studies of microcirculation and haemodynamics was evaluated. The spatial and temporal characteristics of human pulsatile brain-tissue movements in healthy individuals, relevant for the understanding of the cerebrospinal-fluid (CSF) circulation and the pathogenesis of hydrocephalus, were thoroughly investigated. READ MORE

4. 2. NMR Imaging of Flow and Perfusion using Hyperpolarized Nuclei: Theoretical Considerations and Application to Experimental Models

   Author : Edvin Johansson; Lund Medicinsk strålningsfysik; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Nukleärmedicin; radiobiologi; radiobiology; Nuclear medicine; Perfusion; Macroscopic flow; Hyperpolarized tracers; Nuclear magnetic resonance NMR ; Magnetic resonance imaging MRI ;

   Abstract : 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. READ MORE

5. 3. Perfusion computed tomography of the liver

   Author : Katharina Brehmer; Karolinska Institutet; Karolinska Institutet; []
   Keywords : ;

   Abstract : Background: Perfusion CT (P-CT) is a relatively new imaging technique that permits the visual and quantitative assessment of the micro- and macrocirculation of a target organ and focal lesions. P-CT has shown promising results in the evaluation of hyper-vascular tumors such as hepatocellular carcinoma (HCC). READ MORE

6. 4. Characterization of the BOLD signal in functional MRI

   Author : Tomas Jonsson; Karolinska Institutet; Karolinska Institutet; []
   Keywords : ;

   Abstract : In the last two decades, functional magnetic resonance imaging (fMRI) has become an important and widely used imaging technique for functional brain mapping. However, blood oxygen level dependent (BOLD) technique is quite insensitive and task invoked BOLD signal change at 3T is typically in the order of a few percent. READ MORE

7. 5. WAVELET NOISE REDUCTION AND VASCULAR WATER TRANSPORT MODELLING : APPLICATIONS TO DIFFUSION AND PERFUSION MRI

   Author : Adnan Bibic; Lund Medicinsk strålningsfysik; []
   Keywords : 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;

   Abstract : 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. READ MORE