Essays about: "Dose Heterogeneity"

Showing result 1 - 5 of 6 essays containing the words Dose Heterogeneity.

1. 1. COMPARISON OF MULTI-CRITERIA OPTIMIZATION IN TWO DIFFERENT TREATMENT PLANNING SYSTEMS

   University essay from

   Author : Anna Lindström; [2021-05-10]
   Keywords : Medical physics; Multi-criteria optimization; Pareto front; volumetric modulated arc therapy; head and neck cancer; prostate cancer;

   Abstract : Purpose: The purpose with this study was to compare multi-criteria optimization (MCO) for volumetric modulated arc therapy (VMAT) treatment plans in two different treatment planning systems. Theory: When performing treatment planning prior to radiation therapy it is important to prioritize between absorbed dose to target and absorbed dose to organs at risk (OAR). READ MORE

3. 2. Investigation of a Collapsed Cone Superposition Algorithm for dosimetry in brachytherapy

   University essay from Stockholms universitet/Fysikum

   Author : Freja Alpsten; [2021]
   Keywords : Brachytherapy; Collapsed Cone; Model-Based Dose Calculation Algorithms; Radiotherapy;

   Abstract : Background & Purpose: The current standard dosimetry in brachytherapy treatment planning, the TG-43 formalism, ignore the presence of non-water media and finite patient dimensions. This can cause clinically relevant errors in dose estimates. READ MORE

4. 3. Towards unification of organ labeling in radiation therapy using a machine learning approach based on 3D geometries

   University essay from KTH/Skolan för elektroteknik och datavetenskap (EECS)

   Author : Giorgio Ruffa; [2019]
   Keywords : ;

   Abstract : In radiation therapy, it is important to control the radiation dose absorbed by Organs at Risk (OARs). The OARs are represented as 3D volumes delineated by medical experts, typically using computed tomography images of the patient. READ MORE

5. 4. Spatial Frequency-Based Objective Function for Optimization of Dose Heterogeneity in Grid Therapy

   University essay from Stockholms universitet/Fysikum

   Author : Fredén Emil; [2019]
   Keywords : Radiotherapy; Dose Optimization; Objective function; Dose Heterogeneity; Proton Grid Therapy; Spatially Fractionated Radiotherapy; SFRT;

   Abstract : In this project we introduced a spatial frequency-based objective function for optimization of dose distributions used in spatially fractionated radiotherapy (also known as grid therapy). Several studies indicate that tissues can tolerate larger mean doses of radiation if the dose is delivered heterogeneously or to a partial volume of the organ. READ MORE

6. 5. 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/Sjukhusfysikerutbildningen

   Author : Mohammed Mosad Said; [2016]
   Keywords : Medicine and Health Sciences;

   Abstract : 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