Essays about: "Organs-at-risk"

Showing result 21 - 25 of 36 essays containing the word Organs-at-risk.

  1. 21. A comparative treatment planning study of radiotherapy of clinical liver- and stomach-cancer cases with either photon or proton beams

    University essay from Stockholms universitet/Fysikum

    Author : Gracinda Mondlane; [2014]
    Keywords : ;

    Abstract : There has been an increasing interest in proton beam therapy (PBT) in recent years related to the advantageous depth-dose characteristics of proton beams compared to what is achievable with standard external photon beam radiotherapy (RT). With PBT, improved target dose conformity can be achieved together with a reduction in the dose to the organs at risk (OARs). READ MORE

  3. 22. Robustness of the voluntary breath-hold approach for the treatment of early stage lung cancer with spot scanned proton therapy

    University essay from Lunds universitet/Sjukhusfysikerutbildningen

    Author : Jenny Dueck; [2013]
    Keywords : Medicine and Health Sciences;

    Abstract : Background: Intra- and interfractional variations in anatomy can cause unplanned substantial alterations of the dose distribution of the target in proton therapy. Motion management methods might be used in order to minimize anatomical variations. READ MORE

  4. 23. Breathing interplay effects during Tomotherapy. A 3D gel dosimetry study

    University essay from Lunds universitet/Sjukhusfysikerutbildningen

    Author : Anna Ljusberg; [2013]
    Keywords : Medicine and Health Sciences;

    Abstract : Tomotherapy delivers intensity modulated radiation therapy, IMRT, which enables highly advanced treatment plans with homogenous absorbed dose coverage of the target with sharp dose gradients to spare surrounding healthy tissue. Helical tomotherapy consists of a linear accelerator mounted on a rotating gantry, the construction is similar to a CT although the energy is in the MV-range instead of kV and extra collimators and beam stopper are inserted [1-3]. READ MORE

  5. 24. Prototype Development of an A-Mode Ultrasound Based Intrafraction Motion Management System

    University essay from KTH/Skolan för teknik och hälsa (STH)

    Author : Abebe Hailu; Fredrik Lundqvist; [2013]
    Keywords : Intrafraction motion management; A-mode ultrasound; stereotactic body radiation therapy; ultrasonic distance measurement; embedded system;

    Abstract : Owing to the steep dose fall-off curves of high precision and accuracy radiation therapy (RT) modalities such as stereotactic body RT (SBRT), treatment plans with extraordinarily small margins to organs at risk (OARs), such as the spinal cord, has been made possible. With this development, patient movements during treatment, i.e. READ MORE

  6. 25. Automatic Localization of Bounding Boxes forSubcortical Structures in MR Images UsingRegression Forests

    University essay from KTH/Skolan för datavetenskap och kommunikation (CSC)

    Author : Lars Lowe Sjösund; [2013]
    Keywords : ;

    Abstract : Manual delineation of organs at risk in MR images is a very time consuming task for physicians, and to be able to automate the process is therefore highly desirable. This thesis project aims to explore the possibility of using regression forests to nd bounding boxes for general subcortical structures. READ MORE