Amorphous Silicon Flat Panel Detector Improvements and Applications in Radiotherapy

Abstract

Mitterlechner Bernhard

Radio-therapeutic treatment pursues to highly accurately deliver therapeutic radiation dose to the tumor target volume while spearing organs at risk as well as healthy tissue. More advanced irradiation technologies like Aperture Based Image Guided Radiotherapy (abIGRT) or Intensity Modulated Radiotherapy (IMRT) adapt the irradiation fields by the means of jaws and the Multi-Leaf Collimator (MLC) to the appropriate target volume. Important quality issues are therefore the position accuracy and reproducibility of the leaves and jaws. Already existing calibration methods require additional hard- and software and so, an Electronic Portal Imaging Device (EPID) based solution for calibrating jaws and the MLC was developed. Hence, portal images from predefined field prescriptions are acquired, field penumbras analyzed and out of those results, jaws and leaves can be calibrated. The software developments are based on the open-radART framework, which is developed at the University Clinic for Radiotherapy and Radio-Oncology, as well as on the Institute for Research and Development on advanced Radiation Technology (radART) of the Paracelsus Medical University (PMU).