Sökning: "artefakter ct"

Visar resultat 1 - 5 av 12 uppsatser innehållade orden artefakter ct.

  1. 1. Evaluation of a Novel Reconstruction Framework for Gamma Knife Cone-Beam CT - The Impact of Scatter Correction and Noise Filtering on Image Quality and Co-registration Accuracy

    Master-uppsats, KTH/Fysik

    Författare :Ida Hägnestrand; [2023]
    Nyckelord :Gamma Knife; Cone-beam computed tomography; Image quality; Image reconstruction; Co-registration; Contrast; Uniformity; Spatial resolution; Scatter correction; Wiener filter; Noise filter; Patient positioning; Stereotactic radiosurgery; Gammakniv; Strålkniv; Cone-Beam Computed Tomography; Bildkvalitet; Bildrekonstruktion; Co-registrering; Kontrast; Uniformitet; Spatial upplösning; Spridningskorrigering; Wienerfilter; Brusfilter; Stereotaktisk strålkirurgi;

    Sammanfattning : The Gamma Knife is a non-invasive stereotactic radiosurgery system used for treatments of deep targets in the brain. Accurate patient positioning is needed for precise radiation delivery to the target. LÄS MER

  3. 2. 3d-utskrivet fantom för kontroll av linjär-acceleratorer

    Uppsats för yrkesexamina på grundnivå, Umeå universitet/Institutionen för tillämpad fysik och elektronik; Umeå universitet/Centrum för medicinsk teknik och fysik (CMTF)

    Författare :Simon Selin; [2023]
    Nyckelord :3D; print; phantom; quality control; linear accelerator; artefacts; 3D-utskrift; fantom; kvalitetskontroll; linjäracceleratorer; artefakter;

    Sammanfattning : Cancer är en sjukdom som var tredje person får som diagnos under en livstid. Stor del av dessa cancerpatienter får behandling med hjälp av strålbehandling. Där strålbehandlingen kan ske med en linjäraccelerator. Linjäracceleratorn producerar elektron eller fotonstrålning i Mega Volt energiområde. LÄS MER

  4. 3. Respiratory Motion Correction in PET Imaging: Comparative Analysis of External Device and Data-driven Gating Approaches

    Master-uppsats, KTH/Fysik

    Författare :Nina Lindström Söraas; [2023]
    Nyckelord :PET CT; Tomographic reconstruction; Respiratory gating techniques; Image registration; Motion correction; PET CT; Tomografisk rekonstruktion; Gating tekniker; Bildregistrering; Rörelsekorrigering;

    Sammanfattning : Positron Emission Tomography (PET) is pivotal in medical imaging but is prone to artifactsfrom physiological movements, notably respiration. These motion artifacts both degradeimage quality and compromise precise attenuation correction. LÄS MER

  5. 4. Deep Ring Artifact Reduction in Photon-Counting CT

    Master-uppsats, KTH/Fysik

    Författare :Konstantinos Liappis; [2022]
    Nyckelord :Photon¬counting; Spectral CT; Material Decomposition; Deep learning; Resnet; Ring artifact; Sinogram; Fotonräknande; Spektral datortomografi; Materialdekomposition; Djupinlärning; Resnet; Ringartefakt; Sinogram;

    Sammanfattning : Ring artifacts are a common problem with the use of photon-counting detectors and commercial deployment rests on being able to compensate for them. Deep learning has been proposed as a candidate for tackling the inefficiency or high cost of traditional techniques. LÄS MER

  7. 5. Preparations for photon external beam radiotherapy treatment planning of small animals

    Master-uppsats, Lunds universitet/Sjukhusfysikerutbildningen

    Författare :Joanie Diha Guei; [2022]
    Nyckelord :Medicine and Health Sciences;

    Sammanfattning : Introduction:The XenX is a small animal irradiation system that acquires high-resolution cone-beam tomography (CBCT) images of small animals and treats small animals with higher precision than medical linear accelerators. MuriSlice is a software for CBCT image reconstruction. LÄS MER