Search for dissertations about: "Medical Radiation Physics"

Showing result 1 - 5 of 178 swedish dissertations containing the words Medical Radiation Physics.

  1. 1. Quality assurance for magnetic resonance imaging (MRI) in radiotherapy

    University dissertation from Umeå : Department of radiation sciences, Umeå university

    Author : Mary Adjeiwaah; Tufve Nyholm; Rob HN Tijssen; [2017]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic resonance imaging; Radiotherapy; geometric distortions; patient-induced susceptibilities MR-only; radiofysik; radiation physics;

    Abstract : Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. READ MORE

  2. 2. The microdosimetric variance-covariance method used for beam quality characterization in radiation protection and radiation therapy

    University dissertation from Stockholm : Medicinsk strålningsfysik (tills m KI)

    Author : Jan Erik Lillhök; Lennart Lindborg; Bernd Grosswendt; [2007]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; ionizing radiation; radiation quality; radiation protection; radiation therapy; microdosimetry; nanodosimetry; variance-covariance method; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik; medicinsk strålningsfysik; Medical Radiation Physics;

    Abstract : Radiation quality is described by the RBE (relative biological effectiveness) that varies with the ionizing ability of the radiation. Microdosimetric quantities describe distributions of energy imparted to small volumes and can be related to RBE. READ MORE

  3. 3. Spectral Mammography with X-Ray Optics and a Photon-Counting Detector

    University dissertation from Stockholm : KTH

    Author : Erik Fredenberg; Mats Danielsson; Björn Cederström; Jeffrey H. Siewerdsen; [2009]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; mammography; x-ray optics; photon counting; spectral shaping; spectral imaging; collimation; radiation dose; signal-to-noise ratio; quantum noise; anatomical noise; spatial resolution; x-ray flux; ; TECHNOLOGY; TEKNIKVETENSKAP; TECHNOLOGY Engineering physics; TEKNIKVETENSKAP Teknisk fysik; TECHNOLOGY Engineering physics Optical physics; TEKNIKVETENSKAP Teknisk fysik Optisk fysik; TECHNOLOGY Engineering physics Other engineering physics; TEKNIKVETENSKAP Teknisk fysik Övrig teknisk fysik; TECHNOLOGY Electrical engineering; electronics and photonics; TEKNIKVETENSKAP Elektroteknik; elektronik och fotonik; TECHNOLOGY Other technology Medical engineering; TEKNIKVETENSKAP Övriga teknikvetenskaper Medicinsk teknik; MEDICINE Physiology and pharmacology Radiological research; MEDICIN Fysiologi och farmakologi Radiologisk forskning;

    Abstract : Early detection is vital to successfully treating breast cancer, and mammography screening is the most efficient and wide-spread method to reach this goal. Imaging low-contrast targets, while minimizing the radiation exposure to a large population is, however, a major challenge. READ MORE

  4. 4. Energy and intensity modulated radiation therapy with electrons

    University dissertation from Umeå : Umeå universitet

    Author : Lennart Olofsson; Mikael Karlsson; Magnus Karlsson; Björn Zackrisson; Erik Traneus; [2005]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Radiation sciences; Radiation therapy; Conformal therapy; IMRT; Electrons; Electron treatment head; Electron MLC; Bremsstrahlung reduction; Integral dose; Penumbra; Output factor; Strålningsvetenskap; MEDICINE Physiology and pharmacology Radiological research Radiation biology; MEDICIN Fysiologi och farmakologi Radiologisk forskning Strålningsbiologi; radiofysik; radiation physics;

    Abstract : In recent years intensity modulated radiation therapy with photons (xIMRT) has gained attention due to its ability to reduce the dose in the tissues close to the tumour volume. However, this technique also results in a large low dose volume. READ MORE

  5. 5. Ion recombination in liquid ionization chambers development of an experimental method to quantify general recombination

    University dissertation from Umeå : Umeå universitet

    Author : Jonas Andersson; Heikki Tölli; Lennart Johansson; Anders Ahnesjö; [2013]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; General recombination; initial recombination; liquid ionization chamber; radiation dosimetry; radiofysik; radiation physics;

    Abstract : An experimental method (the two-dose-rate method) for the correction of general recombination losses in liquid ionization chambers has been developed and employed in experiments with different liquids and radiation qualities. The method is based on a disassociation of initial and general recombination, since an ionized liquid is simultaneously affected by both of these processes. READ MORE