Sökning: "Spectral CT"

Visar resultat 1 - 5 av 14 uppsatser innehållade orden Spectral CT.

  1. 1. Improving proton therapy planning with photon-counting spectral computed tomography

    Master-uppsats, KTH/Fysik

    Författare :Karin Larsson; [2023]
    Nyckelord :Proton therapy; Medical imaging; Computed Tomography; Protonterapi; Medicinsk avbildning; Datortomografi;

    Sammanfattning : Proton radiation therapy is an alternative to conventional photon radiation therapy, which accounts for the majority of radiation treatments today. The rationale for using protons in radiation therapy lies in their dose deposition properties; photons deposit a radiation dose inversely proportional to the energy, and therefore tissue depth, while protons exhibit a sharp Bragg peak when traversing matter. LÄS MER

  3. 2. 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

  4. 3. Learning the Forward Operator in Photon-Counting Computed Tomography

    Master-uppsats, KTH/Matematik (Avd.)

    Författare :Emanuel Ström; [2021]
    Nyckelord :Photon-Counting; Computed Tomography; Spectral CT; Regularisation; Deep Learning; Fotonräknande; Datortomografi; Spektral CT; Regularisering; Djupinlärning;

    Sammanfattning : Computed Tomography (CT) is a non-invasive x-ray imaging method capable of reconstructing highly detailed cross-sectional interior maps of an object. CT is used in a range of medical applications such as detection of skeletal fractures, organ trauma and artery calcification. LÄS MER

  5. 4. Evaluation of deep-learning image reconstruction for photon-counting spectral CT : A comparison between image domain- and projection domain-denoising

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Morris Eriksson; Hannes Karlsson; [2021]
    Nyckelord :;

    Sammanfattning : A promising new technology in medical imaging is photon-counting detectors (PCD). Itcould allow for images with higher resolution, less noise, improved material decomposi-tion while possibly reducing radiation exposure for patients. LÄS MER

  7. 5. Event-based High Resolution X-ray Imaging using Compton Coincidence Detection

    Master-uppsats, KTH/Medicinsk avbildning

    Författare :Eva Bergström; [2021]
    Nyckelord :Photon counting CT; Compton scattering; Compton kinematics; coincidence detection; χ2 test; Fotonräknande CT; Compton-spridning; Compton-kinematik; sammanfallsdetektering; χ2 -test;

    Sammanfattning : Research on photon counting detectors (PCDs) is focused on semiconductor materials, and silicon is a strong candidate to use in PCDs for photon counting computer tomography (CT). In a silicon detector, a significant portion of the counts is due to Compton scattering events. LÄS MER