Sökning: "Dose planning"

Visar resultat 6 - 10 av 120 avhandlingar innehållade orden Dose planning.

  1. 6. Development and evaluation of an independent system for absorbed dose calculations in radiotherapy

    Författare :Stefan Johnsson; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; medicinsk instrumentering; tomografi; radiologi; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; cancer; Cytologi; onkologi; cancerology; oncology; Cytology; PDA; mini-phantom; in-air equivalence; primary kerma; transmission measurement; stopping power ratio; entrance dose; beam quality; quality control; error prevention; monitor unit calculation; radiation therapy; dose calculation;

    Sammanfattning : The aim of this work was to develop, implement and evaluate an independent system with which to calculate the absorbed dose, delivered by high-energy X-ray beams, to the prescription point and the depth of dose maximum. The introduction of such a system in the clinical routine may help ensure high-quality treatment and avoidance of errors which may jeopardise the clinical outcome of the treatment (i. LÄS MER

  3. 7. Cone Beam Computed Tomography - radiation dose and image quality assessments

    Författare :Sara Lofthag-Hansen; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Cone beam computed tomography; anatomic landmarks; dose-area product; image quality; implant planning; periapical diagnosis; radiation dosimetry;

    Sammanfattning : Diagnostic radiology has undergone profound changes in the last 30 years. New technologies are available to the dental field, cone beam computed tomography (CBCT) as one of the most important. LÄS MER

  4. 8. Radioiodine Therapy of Hyperthyroidism - Simplified patient-specific absorbed dose planning

    Författare :Helene Jönsson; Malmö Institutionen för kliniska vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiobiologi; Radiofarmaceutisk teknik; Radiopharmaceutical technology; absorbed dose. optimise; hyperthyroidism; therapy; 131-I; radioiodine; Nukleärmedicin; radiobiology; Nuclear medicine;

    Sammanfattning : Radioiodine therapy of hyperthyroidism is the most frequently performed radiopharmaceutical therapy. To calculate the activity of 131-I to be administered for giving a certain absorbed dose to the thyroid, the mass of the thyroid and the individual biokinetic data, normally in the form of uptake and biologic half-time, have to be determined. LÄS MER

  5. 9. 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

  7. 10. Contouring & planning variability in stereotactic radiosurgery : How to assess and address the weakest link in stereotactic radiosurgery?

    Författare :Helena Sandström; Iuliana Toma-Dasu; David Schlesinger; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stereotactic radiosurgery; contouring variability; robust treatment planning; Medical Radiation Physics; medicinsk strålningsfysik;

    Sammanfattning : The use of stereotactic radiosurgery (SRS) employing one or a few fractions of high doses of radiation has continuously increased due to the technical development in dose delivery and morphological and functional imaging. As the target volume in SRS is usually defined without margins, the treatment success critically depends on accurate definition and contouring of the target volume and organs at risk (OARs) which are commonly situated in the proximity of the target making their precise delineation particularly important in order to limit possible normal tissue complications. LÄS MER