Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"Radiology and Medical Imaging"”.
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Breast Tomosynthesis: Aspects on detection and perception of simulated lesions
… of simulated lesions (microcalcifications and masses) in digital mammography (DM) and breast tomosynthesis (BT). Perception in BT image volumes were also investigated by evaluating certain reading conditions. The first study concerned the effect of system noise on the detection of masses …
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Optimization of image quality and radiation dose in neuroradiological computed tomography
… of image quality, with increased image noise and reduced spatial resolution, is a major limitation for radiation dose reduction in CT. This can be counteracted with new post-processing image filters and iterative reconstruction (IR) algorithms that improve image quality and allow for reduced …
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Mammographic density in relation to breast cancer Tumor characteristics, mode of detection, and density assessments
… reflects the composition of the breast tissue and can be measured by different methods. Mammography has a lower sensitivity in women with dense breasts, and women with dense breasts have a higher incidence of breast cancer than do women with non–dense breasts. Furthermore, there has been an …
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Exercise capacity with special reference to type 2 diabetes
Physical inactivity and obesity is a growing health problem world wide. Three different samples with a wide range of glucose tolerance were included in the thesis to represent a wider population. The exercise capacity was studied in one group of healthy sedentary middle aged men with normal glucose …
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Hyperpolarized 3He-diffusion MRI in evaluation of lung structure in emphysema. Validation and development of the method
… COPD is a major cause of chronic morbidity and mortality throughout the world. It is a preventable and treatable disease. Smoking is the most commonly encountered risk factor for COPD and the habit now unfortunately starts at earlier ages than before. There is a strong necessity to diagnose …
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Lung function in smokers - Aspects on COPD diagnosis and associations to atherosclerosis and alcohol consumption
Smoking is the most common and important risk factor for reduced lung function. Chronic Obstructive Pulmonary Disease (COPD) affects mainly smokers and is characterized by airflow obstruction, assessed using one of two major diagnostic spirometric criteria. Aspects of lung function besides …
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Three-dimensional T1 quantification techniques for assessment of cartilage quality using dGEMRIC
Osteoarthritis (OA) is a common chronic disease and one of the major global causes for functional disabilities. The disease is characterized by loss and degradation of cartilage, commonly affecting the knees and hips. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is a previously presented …
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Measurement of Tumor Extent and Effects of Breast Compression in Digital Mammography and Breast Tomosynthesis
… size is an important predictor of prognosis and treatment effect. We hypothesized that the tumor outline would be better defined in BT and therefore tumor measurement in BT would be more accurate compared with DM. The results showed that breast tumor size measured on BT correlated better with …
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Tomosynthesis in pulmonary cystic fibrosis
… be used in pulmonary cystic fibrosis, to design and validate a tomosynthesis scoring system, and to determine the effective dose from chest tomosynthesis in children. In a prospective study starting in 2008 clinical chest radiography or computed tomography (CT) were supplemented with a …
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fMRI for mapping the plastic somatotopy of primary somatosensory cortex - Development and clinical applications
Functional magnetic resonance imaging (fMRI) is a widely used tool for studying brain function in vivo. The technique is based on acquiring brain images sensitive to the physiological response following neural activation, and hence, allows brain activity to be examined and documented. In this …
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Radiation exposure of human populations in villages in Russia and Belarus affected by fallout from the Chernobyl reactor
… fallout affected all the European countries and most severely the three countries of Belarus, Russia and Ukraine. In the aftermath of this devastating event, the scientific knowledge on the various radiological impacts of such a large scale accident and means to remediate these impacts has …
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Quantification of Fat Content and Fatty Acid Composition Using Magnetic Resonance Imaging
In obesity and several other disease scenarios, the measurement of fat accumulation in various organs and tissues has become a sought-after technique in clinical diagnostics and research. Especially, quantitative and non-invasive techniques which also provide images of accumulated fat throughout …
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Image Quality Optimisation and Dose Management in CT, SPECT/CT, and PET/CT
… raised concerns about patient radiation exposure and the consequent increased risk of malignancy later in life. The overall objective of this work was to evaluate and optimise different approaches for minimising patient radiation absorbed dose and maintaining or improving image quality in CT, …
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Adolescent Idiopathic Scoliosis. The Role of Low Dose Computed Tomography.
… of new operative methods for correction and stabilization of spinal deformities in young patients with AIS demands a detailed morphological analysis of the vertebral column. CT spine according to protocols available in daily clinical practice means high radiation dose to these young …
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Non-invasive diagnostic methods of intracranial arteries
… magnetic resonance angiography(MRA) techniques and digital subtraction angiography (DSA) in follow-up of intracranial aneurysms treated with coils in order to select the best MRA method, to evaluate the impact of increased iodine concentration in contrast medium and decreased tube voltage on …
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MRI at 3 T of brain functions and fibre tracts adjacent to intracranial tumors
… whether the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) can distinguish tumor-infiltrated edema of gliomas from pure edema of meningiomas and metastases (Paper 4). Results: Strict somatotopic organisation in the primary sensory cortex was shown in the group average; at the …
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Microvascular inflammatory response in the skin
… microvascular response includes vasodilatation and plasma exudation. In the first three studies, the combined response was measured in guinea pig skin with a technique based on detection of radiolabelled protein. Transferrin was labelled in vivo by injection of 113mIn and the conversion …
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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
… 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, 0.05 and 0.1 mmol attenuating atoms/mL were scanned in air and in a 30 cm …