Sökning: "tomografi radiologi medicinsk instrumentering medical instrumentation tomography radiology Clinical"
Visar resultat 1 - 5 av 54 avhandlingar innehållade orden tomografi radiologi medicinsk instrumentering medical instrumentation tomography radiology Clinical.
1. A clinical positron emission tomography facility : 2-¹⁸FDG studies : development and results
Sammanfattning : Positron emission tomography (PET) is a tracer technique used for quantitative in vivo studies of physiological and biochemical processes. Because of the use of positron-emitting radionuclides such as 11-C, 13-N, 15-O and 18-F, which are isotopes of the biologically ubiquitous elements, it is possible to label radiopharmaceuticals which trace biochemical processes precisely. LÄS MER
2. Proton Magnetic Resonance Spectroscopy in Brain Tumors - Clinical Applications
Sammanfattning : Aims: · to present a test phantom and test method for evaluation of proton magnetic resonance spectroscopy (1H-MRS) single volume localization techniques regarding signal contamination; · to describe the introduction of 1H-MRS in the daily routine of a standard MR-unit; · to evaluate the possibilities offered by 1H-MRS to improve preoperative diagnostic accuracy in patients scheduled for stereotactic biopsy of intracranial mass lesions; · to evaluate the possibilities offered by 1H-MRS to improve diagnostics and therapy control in patients with brain abscesses; · to test the hypothesis that 1H-MRS might be useful for differentiation of brain tumors, based on metabolic changes in tissue across brain lesions or surrounding tissue. Results and conclusions: · The test phantom and test method allow quality assessment with good reproducibility. LÄS MER
3. 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
Sammanfattning : 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. LÄS MER
4. Quantifying the quality of medical x-ray images. An evaluation based on normal anatomy for lumbar spine and chest radiography
Sammanfattning : Optimisation in diagnostic radiology requires accurate methods for determination of patient absorbed dose and clinical image quality. Simple methods for evaluation of clinical image quality are at present scarce and this project aims at developing such methods. LÄS MER
5. Are gadolinium contrast media really less nephrotoxic than iodine agents in radiographic examinations? A comparison in relation to their ability to attenuate x-rays in a pig model
Sammanfattning : Purpose: To confront the statement that gadolinium contrast media (Gd-CM) are less nephrotoxic than iodine contrast media (I-CM) when used in x-ray angiographic and computed tomographic (CT) examinations. Methods: I) For CT measurements (mean density in Hounsfield numbers) 20-mL syringes filled with I- and Gd-CM at 0.01, 0.02, 0. LÄS MER
