Innovation in education: Computer simulation in physics training

Abstract

Interest in the application of Computer Simulation within Medical training continues to grow and the use of the VERT (Virtual Environment for Radiotherapy Training) system in radiotherapy training equally so. Herein we explore the use of the VERT system to understand, illustrate and experience the process required to calibrate an ion chamber and use it to obtain an accurate output measurement on a high energy Linac. The VERT system provides a detailed and accurate simulation of conventional Linacs and has a variety of physics activities that mirror the tasks medical physicists are required to become familiar with during their training. One such activity has been implemented to follow the steps defined by the IAEA TRS398 protocol. All activities on the virtual Linac can be undertaken with deliberate errors having been introduced to explore their consequences. The system was used to make the necessary 'measurements' to determine the various calibration factors required to correct the raw electrometer reading for ion recombination, polarity, temperature/pressure. Likewise, the Quality Index of the Linac's 6MV beam was determined to enable the correction of the Absorbed Dose to Water factor measured in the reference Quality. The VERT system provides a simulation environment for training and enhancing the trainees understanding of radiotherapy concepts and practices. Dosimetry practice can be experienced and explored in the classroom during standard working hours rather than waiting until a clinical Linac is available. Random and systematic errors can be introduced, however, the virtual machine can be used without risk of leaving it in a mis-calibrated or unsafe condition.