Sökning: "reconstruction artefacts"

Visar resultat 1 - 5 av 15 uppsatser innehållade orden reconstruction artefacts.

  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. Automatic Detection of Common Signal Quality Issues in MRI Data using Deep Neural Networks

    Master-uppsats, Linköpings universitet/Institutionen för medicinsk teknik

    Författare :Erika Ax; Elin Djerf; [2023]
    Nyckelord :mr; magnetic resonance; machine learning; deep learning; anomaly detection; U-Net; autoencoder; 3D; classification; reconstruction; artefacts;

    Sammanfattning : Magnetic resonance imaging (MRI) is a commonly used non-invasive imaging technique that provides high resolution images of soft tissue. One problem with MRI is that it is sensitive to signal quality issues. The issues can arise for various reasons, for example by metal located either inside or outside of the body. LÄS MER

  4. 3. Quantitative susceptibility mapping of the knee: A comparison of approaches for addressing fatty tissue

    Master-uppsats, Lunds universitet/Sjukhusfysikerutbildningen

    Författare :Cornelia Säll; [2023]
    Nyckelord :Medicine and Health Sciences;

    Sammanfattning : Background/purpose Quantitative susceptibility mapping (QSM) is an MRI-based post processing technique to evaluate the magnetic susceptibility, χ, of human tissue using phase data. While brain imaging has been the most common application, other areas have also raised interest. LÄS MER

  5. 4. 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

  7. 5. Restoring the Already Restored

    Uppsats för yrkesexamina på avancerad nivå, KTH/Arkitektur

    Författare :Hedvig Aaro; [2022]
    Nyckelord :Restoration; preservation; cultural heritage; alteration; museum; Stockholm; Börshuset; historical layers;

    Sammanfattning : Restoration has been a tool for enhancing selected parts of history, which tells about the ideals of its time. Today most older buildings have already been through several restorations or renovations. LÄS MER