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Accumulation of 63Ni, 106Ru and 125Sb in phytoplankton
(2022-08-22)Background: Nuclear Power Plants (NPPs) release small amounts of radionuclides which contribute with a low radiation dose to the environment as well as humans and animals. In this context, marine ecosystems are critical, ... -
APOPTOTIC EFFECTS IN RENAL CORTEX AFTER TREATMENT WITH 177LU-OCTREOTATE
(2021-05-10)Purpose: The purpose of this project was to investigate gene regulation of a predetermined panel of apoptotic genes in murine renal cortex after treatment with 177Lu-octreotate after one day and seven days. Theory: ... -
ATLAS DATABASES OF HUMAN BRAIN ANATOMY: QUALITATIVE AND QUANTITATIVE COMPARISON
(2021-01-11)The purpose of this study was to quantitatively and qualitatively compare the two brain atlases databases, Hammersmith and 2012 MICCAI Multi-Atlas Labelling Challenge data, by developing a quantitative method. Theory Anatomical ... -
ATLAS-BASED SEGMENTATION OF ULTRAHIGH-RESOLUTION STRUCTURAL MR HEAD IMAGES ACQUIRED AT 7 TESLA
(2022-01-13)Purpose: The purpose of this work was to find out how the existing brain atlases and segmentation algorithms perform when applied to ultrahigh-resolution MR brain images, acquired with a 7-Tesla scanner. Also to make ... -
CHARACTERIZATION AND EVALUATION OF A NIPAM POLYMER GEL MRI DOSIMETER SYSTEM
(2022-11-08)Purpose: The normoxic polymer gel dosimeter based on N-isopropyl acrylamide (NiPAM) is a promising full 3D-dosimeter with high spatial resolution and near tissue equivalency. However, limited work have been done in vestigating ... -
Characterization of discrepancies between manual and automatic segmentation to improve anatomical brain atlases
(2021-05-10)Purpose: To characterize discrepancies between expert manually segmented brain images from Hammers Atlas Database and automatically generated segmentations of the same images; to decide whether they can be attributed ... -
COMPARISON OF MULTI-CRITERIA OPTIMIZATION IN TWO DIFFERENT TREATMENT PLANNING SYSTEMS
(2021-05-10)Purpose: The purpose with this study was to compare multi-criteria optimization (MCO) for volumetric modulated arc therapy (VMAT) treatment plans in two different treatment planning systems. Theory: When performing ... -
Deep Neural Networks for Noise Reduction and Bias Removal in MR Diffusion Signal
(2022-03-22)The purpose of this study is to assess the potential of deep neural networks, trained by unsupervised learning, for diffusion weighted imaging (DWI) data modeling and denoising. DWI data were modeled by a biexponential ... -
DEFORMABLE IMAGE REGISTRATION OF SPINE MAGNETIC RESONANCE IMAGES WITH ELASTIX FOR DETAILED CHARACTERIZATION OF DISC LOADING BEHAVIORS
(2021-05-10)Purpose: This work aimed to develop an optimized strategy for registration of spine magnetic resonance (MR) images acquired with and without spinal loading, as well as evaluate the quality of the registration strategy ... -
DEVELOPMENT, VALIDATION AND APPLICATION OF A METHOD FOR DETERMINATION OF METABOLITE CONCENTRATIONS WITH PRECLINICAL MAGNETIC RESONANCE SPECTROSCOPY
(2021-05-10)Background: Information on the metabolic content in tissue has diagnostic and prognostic value when examining for example cancer and diseases of the brain. MR spectroscopy is a non-invasive method that allows quantification ... -
Effects of reconstruction parameters on the image quality and quantification of PET images from PET/MRI and PET/CT systems
(2022-03-09)Aim: To study how reconstruction parameters affect the positron emission tomography (PET) image quality and quantitative results for the different lesion to background radioactivity ratios in three different PET ... -
ENVIRONMENTAL RADIOLOGICAL STUDIES OF KVARNTORPSHÖGEN Dose and Radiological Risk Assessments for Humans and Biota
(2021-04-06)Background: The pile Kvarntorpshögen and the lakes Surpölen and Norrtorpssjön are the remains of an industry which mined and processed oil shales to extract oil during World War II. The pile mainly consists of shale ... -
Establishment of a deep learning algorithm for dosimetry of radiopharmaceuticals
(2022-01-13)Purpose: The aim of this study was to introduce a volumetric convolutional neural network for segmentation of the kidneys in SPECT images and to apply it in the dosimetry of radiopharmaceuticals of this organ, in order ... -
ESTIMATION OF RADIATION EXPOSURE FROM NATURALLY OCCURRING RADIONUCLIDES IN FOOD AND FOODSTUFF
(2022-01-13)Purpose: The main purpose of this study was to provide an estimation of the committed effective dose received by the Swedish population from naturally occurring radionuclides (NORM) in the diet. This study was also ... -
Evaluation of deep learning image reconstruction for brain- and abdominal CT - A visual grading characteristics study
(2022-05-04)Computed tomography (CT) is a common medical imaging method today. There are different ways of reconstructing the images from a CT examination. The standard method is the filtered back projection (FBP). However, a disadvantage ... -
EVALUATION OF RADIATION DOSES USING CONE BEAM COMPUTED TOMOGRAPHY IN ENDOVASCULAR AORTIC REPAIR AND SCOLIOSIS PROCEDURES
(2021-04-06)Purpose: The study includes the two areas, vascular surgery and orthopedics, and focuses on endovascular aortic aneurysm repair (EVAR) and scoliosis procedures. EVAR procedures contribute to a high radiation dose to ... -
Evaluation of the DXA radiation environment at Sahlgrenska University Hospital
(2022-05-18)Purpose: The aims of this work were to evaluate the radiation environment in the dual-energy X-ray absorptiometry (DXA) rooms at Sahlgrenska University Hospital, estimate personnel doses, determine legal requirements for ... -
Evaluation of the iterative kilovoltage cone-beam computed tomography reconstruction method for the Varian TrueBeam system
(2022-03-18)Introduction: Radiotherapy is used to treat patients with various types of cancer, where linear accelerators produce the radiation beam used for the treatment. Before each treatment fraction, the patient needs to be ... -
Evaluation of whole-body bone scans performed using a gamma camera with Cadmium Zinc Telluride detector
(2022-01-13)The bone scan is a common nuclear medicine imaging procedure that is mainly used for evaluating several oncological patient groups. A radioactive tracer, 99mTc -labelled diphosphonate, is injected intravenously and ... -
FETAL DOSE ESTIMATION IN ABDOMINAL AND PELVIC CT EXAMINATIONS
(2021-05-10)Purpose: The purpose of this is study was to compare different methods for estimating the fetal dose, how much the different methods differ from each other and on which dose levels the fetal doses are estimated to. ...