Sökning: "radiation therapy"

Visar resultat 1 - 5 av 256 avhandlingar innehållade orden radiation therapy.

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

    Detta är en avhandling från Stockholm : Medicinsk strålningsfysik (tills m KI)

    Författare :Jan Erik Lillhök; Stockholms universitet.; [2007]
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

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

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Lennart Olofsson; Umeå universitet.; [2005]
    Nyckelord :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; radiofysik;

    Sammanfattning : 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. LÄS MER

  3. 3. Implementation of MRI gel dosimetry in radiation therapy

    Detta är en avhandling från Department of Radiation Physics, Lund university

    Författare :Sven Bäck; Lund University.; Lunds universitet.; [1998]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; oncology; Cytology; uncertainty; detector; dosimeter; ferrous ions; gel dosimetry; magnetic resonance imaging; monomers; polymerisation; proton; treatment planning verification; radiation therapy; cancerology; Cytologi; onkologi; cancer;

    Sammanfattning : Gel dosimetry was used together with magnetic resonance imaging (MRI) to measure three-dimensional absorbed dose distributions in radiation therapy. Two different dosimeters were studied: ferrous- and monomer gel, based on the principles of radiation-induced oxidation and polymerisation, respectively. LÄS MER

  4. 4. Modelling late toxicity in hypofractionated radiation therapy

    Detta är en avhandling från Department of Radiation Physics, Lund university

    Författare :Niclas Pettersson; Göteborgs universitet.; Gothenburg University.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hypofractionation; normal tissue complication probability; modelling; linear-quadratic model; fractionation sensitivity; late toxicity; radiation-induced rib fracture; genitourinary toxicity; stereotactic body radiation therapy; high-dose-rate brachytherapy; multimodality radiation therapy; patient-reported outcomes; prostate cancer; nsclc;

    Sammanfattning : In hypofractionated radiation therapy (RT), the treatment is delivered by few fractions with high doses per fraction. This is in contrast to conventionally fractionated RT where the total dose is delivered in many fractions with low doses per fraction. LÄS MER

  5. 5. Accurate description of heterogeneous tumors for biologically optimized radiation therapy

    Detta är en avhandling från Stockholm : Medicinsk strålningsfysik (tills m KI)

    Författare :Johan Nilsson; Stockholms universitet.; [2004]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; heterogeneous tumors; radiation therapy; biological optimization; tumor hypoxia; effective radiation sensitivity; effective radiation resistance; MEDICINE Physiology and pharmacology Radiological research Radiation biology; MEDICIN Fysiologi och farmakologi Radiologisk forskning Strålningsbiologi;

    Sammanfattning : In this thesis, a model of tissue oxygenation is presented, that takes into account the heterogeneous nature of tumor vasculature. Even though the model is rather simple, the resulting oxygen distributions agree very well with clinically observed oxygen distributions for most tumors and healthy normal tissues. LÄS MER