Sökning: "computed-tomography"

Visar resultat 21 - 25 av 481 avhandlingar innehållade ordet computed-tomography.

  1. 21. Spectral Photon-Counting Computed Tomography with Silicon Detectors: New Models and Applications

    Författare :Fredrik Grönberg; Mats Danielsson; Mats Persson; Amir Pourmorteza; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photon-counting; spectral computed tomography; material decomposition; pulse pileup; Compton scatter; image formation; fotonräknande; spektral datortomografi; materialbasupdelning; pulsöverlagring; Comptonspridning; bildbildning; Physics; Fysik;

    Sammanfattning : X-ray computed tomography (CT) is a widely used imaging modality that enables visualization of nearly every part of the human body. It is used for diagnosis of disease and injury as well as medical treatment planning. LÄS MER

  3. 22. An Event-Reconstructing Silicon Detector for 1 µm Resolution Spectral Computed Tomography

    Författare :Christel Sundberg; Mats Danielsson; Julia Herzen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; photon-counting; silicon detector; spectral computed tomography; subpixel resolution; dose efficiency; coincidence tracking; event reconstruction; fotonräknande; kiseldetektor; spektral datortomografi; subpixelupplösning; doseffektivitet; koincidensspårning; händelserekonstruktion; Fysik; Physics;

    Sammanfattning : Computed tomography (CT) is a medical imaging modality in which cross-sectional images of the human body are created using x-rays. Commercial CT scanners utilize energy-integrating detectors to measure the x-ray attenuation. However, photon-counting detectors with energy-discriminating abilities have started to emerge. LÄS MER

  4. 23. Cone Beam Computed Tomography - radiation dose and image quality assessments

    Författare :Sara Lofthag-Hansen; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cone beam computed tomography; anatomic landmarks; dose-area product; image quality; implant planning; periapical diagnosis; radiation dosimetry;

    Sammanfattning : Diagnostic radiology has undergone profound changes in the last 30 years. New technologies are available to the dental field, cone beam computed tomography (CBCT) as one of the most important. LÄS MER

  5. 24. Effects of nonlinear noise reduction algorithms on image quality in computed tomography systems. Evaluations using human observers and methods for assessing distortion

    Författare :Joel Larsson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Computed Tomography; Nonlinear noise reduction; Visual grading; Distortion analysis;

    Sammanfattning : Many conventional radiological examinations have during the past decades been replaced by examinations performed on computed tomography (CT) systems. One reason is that a CT system, in contrast to a conventional X-ray system, depicts slices of the body so that anatomical structures to a lesser extent risk to obscure the potential pathology. LÄS MER

  7. 25. Intravenous contrast media optimization at computed tomography

    Författare :Anders Svensson; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : The administration of intravenous contrast media (IV CM) is essential for detecting lesions at most computed tomography (CT) examinations. The overall aim of this thesis is to investigate different aspects of IV CM administration that may affect the quality of the CT examination. LÄS MER