Search for dissertations about: "quantitative computed tomography"

Showing result 1 - 5 of 75 swedish dissertations containing the words quantitative computed tomography.

  2. 1. Quantitative SPECT : studies of some factors influencing quantitation accuracy in single photon emission computed tomography

    Author : Bertil Axelsson; Stockholms universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES;

    Abstract : .... READ MORE

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

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

    Abstract : 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. READ MORE

  5. 3. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Author : Helén Almquist; Lund Klinisk fysiologi; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; downscatter; myocardial perfustion; ventilation-perfusion ratio; radiologi; pulmonary density; pulmonary perfusion; attenuation correction; SPECT; transmission measurement; tomografi; medicinsk instrumentering;

    Abstract : The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiological and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. READ MORE

  6. 4. 3D nano-tomography using coherent X-rays

    Author : Maik Kahnt; Lunds universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ptychography; Tomography; Phase reconstruction; X-ray microscopy;

    Abstract : X-rays allow to non-destructively investigate biological, chemical or physical processes at the nano-scale. Their high penetration depth in matter allows to investigate samples even inside sample environments, which would be difficult with complementary methods such as transmission electron microscopy (TEM). READ MORE

  7. 5. Spectral Computed Tomography with a Photon-Counting Silicon-Strip Detector

    Author : Mats Persson; Mats Danielsson; Hans Bornefalk; Jiang Hsieh; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Photon-counting; silicon-strip detector; spectral computed tomography; ring artifacts; fluence rate; basis material decomposition; sub-pixel information; Fysik; Physics;

    Abstract : Computed tomography (CT) is a widely used medical imaging modality. By rotating an x-ray tube and an x-ray detector around the patient, a CT scanner is able to measure the x-ray transmission from all directions and form an image of the patient’s interior. READ MORE