Sökning: "metal artifacts"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden metal artifacts.

  1. 1. Metal artifacts in computed tomography : impact of reduction methods on image quality and radiotherapy treatment planning

    Författare :Karin Andersson; Per Thunberg; Eva Norrman; Jan Persliden; Anders Tingberg; Örebro universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; computed tomography; metal artifacts; image quality; visual grading analysis; radiotherapy; proton therapy; hip prosthesis; dental implants;

    Sammanfattning : Degradation of image quality by metal artifacts is a common problem in computed tomography (CT) imaging, which can limit the diagnostic value of a CT examination and also introduce inaccuracies in radiotherapy (RT) treatment planning. In recent years, commercial metal artifact reduction (MAR) methods have been launched by several CT vendors. LÄS MER

  3. 2. Surface reactions on metallic nanoparticles : Ligand adsorption, metal release, and reactive oxygen species generation

    Författare :Amanda Kessler; Inger Odnevall; Tommy Nylander; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; metallic nanoparticles; ROS; reactive oxygen species; metal release; ligand adsorption; corrosion; Fenton like Haber Weiss reactions; metalliska nanopartiklar; ROS; reaktiva syreradikaler; metallfrisättning; adsorption; korrosion; Fenton lika Haber Weiss reaktioner; Kemi; Chemistry;

    Sammanfattning : Humans are exposed daily to metallic nanoparticles (Me NPs) from multiple sources which can have both natural and anthropogenic origins. Such exposures take place via different routes including inhalation and skin contact and may result in adverse health effects. LÄS MER

  4. 3. Laser cleaning as a conservation technique for corroded metal artifacts

    Författare :Yang Sook Koh; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Produktionsutveckling; Manufacturing Systems Engineering;

    Sammanfattning : Preservation of cultural property for the future is one of the most important activities of our society. The information which we can gather from such materials is a valuable key to understanding the past. Conservation is a process which includes a range of different treatments. LÄS MER

  5. 4. Reduction of metal artifacts in MR imaging of patients with total hip arthroplasty

    Författare :Gunilla Müller; Malmö Diagnostisk radiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Magnetic resonance imaging. Musculoskeletal. Hip. Hip prosthesis. Complications. Metal artifact. Metal artifact-reducing sequences MARS . Phantom studies. Artifact measurement. Image distortion.;

    Sammanfattning : Aims of the studies: To apply and compare MR imaging metal artifact reducing sequences (MARS) including subtraction imaging after contrast application in patients with metal-on-metal (MoM) hip prostheses, investigate the prevalence and characteristics of periprosthetic abnormalities, as well as their relation with pain and risk factors. [Paper I]. LÄS MER

  7. 5. High-resolution biomedical phase-contrast tomography

    Författare :William Twengström; Hans Hertz; Anna Burvall; Marco Stampanoni; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; x-ray; x-ray imaging; biomedical; phase contrast; tomography; zebrafish; coronary artery; virtual histology; ring artifacts; phase retrieval; mummy; Fysik; Physics;

    Sammanfattning : Improved three-dimensional biomedical imaging can give a better understanding of tissue structure, growth and diseases. Most present imaging techniques that provide cellular spatial resolution are based on visible or infrared light. These methods cannot image deeper than a millimeter into tissue. LÄS MER