Essays about: "Intensity-Modulated"
Showing result 1 - 5 of 26 essays containing the word Intensity-Modulated.
-
1. Direct optimization of dose-volume histogram metrics in intensity modulated radiation therapy treatment planning
University essay from KTH/Skolan för teknikvetenskap (SCI)Abstract : In optimization of intensity-modulated radiation therapy treatment plans, dose-volumehistogram (DVH) functions are often used as objective functions to minimize the violationof dose-volume criteria. Neither DVH functions nor dose-volume criteria, however,are ideal for gradient-based optimization as the former are not continuously differentiableand the latter are discontinuous functions of dose, apart from both beingnonconvex. READ MORE
-
2. Robust optimization of radiotherapy treatment plans considering time structures of the delivery
University essay from Uppsala universitet/Avdelningen för datalogiAbstract : Cancer is the second largest mortal disease in Sweden, and high efforts are made to develop the treatment of cancer. One of the main treatment methods is radiotherapy, which uses ionizing radiation to damage the cancerous cells. This has the chance of stopping the cell reproduction, and the goal is to reduce the tumor and stop the tumor growth. READ MORE
-
3. Investigation of the prognostic value of CT and PET-based radiomic image features in oropharyngeal squamous cell carcinoma
University essay from Lunds universitet/Medicinsk strålningsfysik, Lund; Lunds universitet/SjukhusfysikerutbildningenAbstract : Background Medical data in the form of radiographic routine scans is steadily accumulating. The analysis of such data through automated quantitative methods is believed to produce new information which would allow for more personalization of therapy. The present thesis investigated the use of such methods in head and neck cancer. READ MORE
-
4. Radiochromic Film Dosimetry in Kilovoltage X-‐ray Beams: A Pre-‐ Investigation for In Vitro Studies of Bystander Effects
University essay from Lunds universitet/Sjukhusfysikerutbildningen; Lunds universitet/Medicinsk strålningsfysik, LundAbstract : Purpose Intensity modulation of radiation is one of several important conditions to evaluate for full understanding of how cells involved in the bystander effect influence each other when cells are exposed to radiation at low and high dose rates. The aim of this study was to develop and apply a useful and practical dosimetric method for measurement of the absorbed dose to cell cultures exposed to intensity modulated radiation in investigations of the bystander effects. READ MORE
-
5. MRI only radiotherapy using synthetic CT images: Dosimetric accuracy and patient positioning strategies in an MRI only workflow
University essay from Lunds universitet/Sjukhusfysikerutbildningen; Lunds universitet/Medicinsk strålningsfysik, LundAbstract : Background and purpose: Magnetic resonance imaging (MRI) only radiotherapy has, due to superior soft tissue contrast of MRI and the possible reduction of systematic uncertainties, grown into a promising technique. The purpose of this work is to investigate parts of an MRI only workflow with synthetic computed tomography (sCT) images generated from MRI. READ MORE
