Background: To correct patient positioning errors (setup errors) during prostate cancer treatment using EPID and fiducial gold markers, to improve the accuracy of the dose delivery in these patients. Materials and Methods: Fifteen patients with localized prostate carcinoma after implantation of fiducial gold markers in their prostate gland underwent the five-field IMRT planning technique. The p...

Currently portal imaging devices are used to obtain information on patient localization during radiation therapy treatments. Such obtained information is two dimensional in nature, limited to the plane of the captured image. It has been proposed that megavoltage computed tomography images be reconstructed to overcome this limitation. This study explores the feasibility of reconstructing tomogra...

Portal imaging is the acquisition of images with a radiotherapy beam. Imaging theory suggests that the quality of portal images could be much higher if the efficiency of the imaging media in detecting radiation could be improved. Introduction of new media (films and electronic portal imaging devices) has confirmed this by markedly increasing the quality of portal images. Images from these devic...

A review of electronic portal imaging devices (EPIDs) used in external beam, megavoltage radiation therapy is presented. The review consists of a brief introduction to the definition, role and clinical significance of portal imaging, along with a discussion of radiotherapy film systems and the motivations for EPIDs. This is followed by a summary of the challenges and constraints inherent to por...

a-Si Electronic Portal Imaging Device (EPID) is an important tool to verify the location of the radiation therapy beam with respect to the patient anatomy. But, Electronic Portal Images (EPI) suffer from low contrast. In order to have better in-treatment images to extract relevant features of the anatomy, image processing tools need to be integrated in the Radiology systems. The goal of this re...

Introduction: The application of 3D volumetric imaging modalities in treatment planning of radiation therapy can provide more precisely define tumor localization, and computed tomography (CT) is the most common accepted method for treatment planning. Given the lack of a CT scanner stationed in all radiotherapy departments and equipping most of the medical linear accelerators wi...

INTRODUCTION Motion of the prostate is problematic in the accurate delivery of external beam radiation therapy (EBRT) for prostate cancer. This study investigated the relationship between body mass index (BMI), an easily measured indicator of obesity, and prostate motion. METHODS Prostate motion during EBRT was assessed by measuring the displacement of fiducial markers implanted within the pr...