Introduction: The accuracy of the patient setup and tumor location are major factors that determine the efficacy of radiotherapy treatment planning. In the prostate radiotherapy, reproducibility of the prostate location for each treatment fraction is problematic owing to varying filling of the rectum and bladder. According to this, the aim of this study was to measure the inte...

PURPOSE to use complementary cine EPID and gimbals log file analysis for in-vivo tracking accuracy monitoring. METHODS A clinical prototype of dynamic tracking (DT) was installed on the Vero SBRT system. This prototype version allowed tumor tracking by gimballed linac rotations using an internal-external correspondence model. The DT prototype software allowed the detailed logging of all appli...

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...

AIM To compare the accuracy of radiotherapy set-up using an electronic portal imaging device (EPID) versus megavoltage cone beam computed tomography (MV-CBCT) in paediatric patients. MATERIALS AND METHODS In total, 204 pairs of EPID and MV-CBCT were carried out for 72 patients in the first 3 treatment days and weekly thereafter. RESULTS For the whole group, the mean systematic EPID set-up e...

background and objectives: for total analytical error, imprecision (sd) and bias, performance goals for laboratory tests have most often been developed. a total analytical error goal requires that the combination of errors from all sources (random and systematic errors) be within some acceptable limit. materials and methods: fifty vials of sodium and potassium standards (sandos company) were ch...

The aim of this study was to assess the performance of a gantry-mounted detector system and a couch set detector system using a systematic multileaf collimator positional error manually introduced for volumetric-modulated arc therapy. Four head and neck and esophagus VMAT plans were evaluated by measurement using an electronic portal imaging device and an ion chamber array. Each plan was copied...

Background and Objectives: For total analytical error, imprecision (SD) and bias, performance goals for laboratory tests have most often been developed. A total analytical error goal requires that the combination of errors from all sources (random and systematic errors) be within some acceptable limit. M...

Purpose: Kilovoltage cone-beam computed tomography (CBCT) has been developed to provide accurate soft-tissue and bony setup information. We evaluated clinical CBCT setup data and compared CBCT measurements with electronic portal imaging device (EPID) images. Material and Methods: The setup error for CBCT scans at the treatment unit relative to the planning CT was measured for 62 patients (524 s...

PURPOSE The aim of this study is to investigate the performance and limitations of a real-time transit electronic portal imaging device (EPID) dosimetry system for error detection during dynamic intensity modulated radiation therapy (IMRT) treatment delivery. Sites studied are prostate, head and neck (HN), and rectal cancer treatments. METHODS The system compares measured cumulative transit E...