Sökning: "Strålbehandling"

Visar resultat 26 - 30 av 81 avhandlingar innehållade ordet Strålbehandling.

1. 26. Photon Dose Calculations in a Fluence-Based Treatment Planning System: Data Processing, Implementation and Validation

   Författare :Lars Weber; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiobiologi; Nuclear medicine; Radiopharmaceutical technology; Radiofarmaceutisk teknik; Nukleärmedicin; radiobiology;

   Sammanfattning : The accuracy of dose calculations for various aspects of a treatment planning system (TPS) using an energy fluence beam modelling has been evaluated. The investigated TPS uses a beam model, which separates the energy fluence into a number of sources in the treatment head. LÄS MER

3. 27. Absorbed Dose Determination and Characteristics of Degraded Electron Beams: Application to Intraoperative Radiation Therapy

   Författare :Peter Björk; Internmedicin - epidemiologi; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering; absorbed dose distribution; output factor; stopping-power ratio; beam characteristics; Monte Carlo calculation; electron beam dosimetry; applicator system; radiation therapy; linear accelerator; intraoperative radiotherapy;

   Sammanfattning : The aim of this work was to quantify limitations of and uncertainties in commonly used dosimetric techniques for relative absorbed dose determination in degraded electron beams, such as those encountered in intraoperative radiation therapy (IORT) and small-electron-field radiotherapy. Three different detector types were investigated with regard to measurements of output factors and relative absorbed dose distributions: (1) a parallel-plate ionization chamber, (2) a p-type silicon diode detector and (3) a diamond detector. LÄS MER

4. 28. Methods for image-based dosimetry and radiobiological modelling in radionuclide therapy

   Författare :Johan Gustafsson; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radionuclide therapy; dosimetry; biologically effective dose; 177Lu-DOTATATE;

   Sammanfattning : In radionuclide therapy (RNT), radioactive pharmaceuticals are administered for therapeutic purposes. Dosimetry, i.e. the estimation of the absorbed dose to various targets, can potentially lead to a better understanding of the therapeutic effects in RNT and allow for individualization of the therapy. LÄS MER

5. 29. 3D Verification of Dynamic and Breathing Adapted Radiotherapy using Polymer Gel Dosimetry

   Författare :Sofie Ceberg; Malmö Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiotherapy; 3D verification; polymer gel;

   Sammanfattning : Polymer gel dosimetry has been used since the 1990s, and several studies have shown that this detector system can be used for verification of static absorbed dose distributions in three dimensions (3D). Its unique properties, such as high resolution, normal tissue equivalence and independency of energy, field size and direction of the incident radiation, should also be advantageous for dosimetric verification of radiotherapy using today’s and tomorrow’s dynamic delivery techniques. LÄS MER

7. 30. Verification of Dose Calculation Algorithms in Treatment Planning Systems for External Radiation Therapy: A Monte Carlo Approach

   Författare :Elinore Wieslander; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiologi; tomografi; medicinsk instrumentering; radiotherapy; dose calculation algorithm; verification; Monte Carlo calculation; electron beam; photon beam; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; treatment planning system;

   Sammanfattning : This thesis presents a new verification concept, the virtual accelerator, for dose calculation algorithms used in treatment planning systems (TPSs) for external beam radiotherapy. The algorithm input data required to implement a treatment unit in the TPS are generated by Monte Carlo simulations as are the beam reference data needed for the subsequent evaluation of the dose calculation algorithm. LÄS MER