Search for dissertations about: "MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik"

Showing result 1 - 5 of 17 swedish dissertations containing the words MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik.

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

    University dissertation from Umeå : Umeå universitet

    Author : Lennart Olofsson; Umeå universitet.; [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; radiofysik;

    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

  2. 2. Improving accuracy of in situ gamma-ray spectrometry

    University dissertation from Umeå : Radiofysik

    Author : Jonas Boson; Umeå universitet.; [2008]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; gamma-ray spectrometry; in situ measurement; HPGe detector; 137Cs; Monte Carlo; efficiency calibration; measurement uncertainty; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik;

    Abstract : Gamma-ray spectrometry measurements performed on site, or “in situ”, is a widely used and powerful method that can be employed both to identify and quantify ground deposited radionuclides. The purpose of this thesis is to improve the calibration of high purity germanium (HPGe) detectors for in situ measurements, and calculate the combined uncertainty and potential systematic effects. READ MORE

  3. 3. Corrections for improved quantitative accuracy in SPECT and planar scintigraphic imaging

    University dissertation from Umeå : Umeå universitet

    Author : Anne Larsson; Umeå universitet.; [2005]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Quantitative SPECT; scintigraphic imaging; attenuation correction; scatter correction; collimator-detector response; septal penetration; background correction; Monte Carlo simulation; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik;

    Abstract : A quantitative evaluation of single photon emission computed tomography (SPECT) and planar scintigraphic imaging may be valuable for both diagnostic and therapeutic purposes. For an accurate quantification it is usually necessary to correct for attenuation and scatter and in some cases also for septal penetration. READ MORE

  4. 4. Verification of dose calculations in radiotherapy

    University dissertation from Umeå : Strålningsvetenskaper

    Author : Tufve Nyholm; Umeå universitet.; [2008]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiotherapy; dose calculation; quality control; pencil kernel; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik;

    Abstract : External radiotherapy is a common treatment technique for cancer. It has been shown that radiation therapy is a both clinically and economically effective treatment for many types of cancer, even though the equipment is expensive. The technology is in constant evolution and more and more sophisticated and complex techniques are introduced. READ MORE

  5. 5. Modeling Silicon Diode Dose Response in Radiotherapy Fields using Fluence Pencil Kernels

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Karin Eklund; Uppsala universitet.; [2010]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICINE Physiology and pharmacology Radiological research Radiological physics; MEDICIN Fysiologi och farmakologi Radiologisk forskning Radiofysik; Medicinsk radiofysik; Medical Radiophysics;

    Abstract : In radiotherapy, cancer is treated with ionizing radiation, most commonly bremsstrahlung photons from electrons of several MeV. Secondary electrons produced in photon-interactions results in dose deposition. The treatment response is low for low doses, raises sharply for normal treatment doses and saturates at higher doses. READ MORE