MLC Transmission and Dosimetric Leaf Gap Measurement Using CU Values from Integrated Images of Varian VitalBeam LINAC.
Modern dynamic radiotherapy techniques require more precision and need routine checking. However, presently available methods for Dosimetric Leaf Gap (DLG) and MLC transmission factor are highly time-consuming, so they are not feasible for busy radiotherapy centers. This analytical and observational study tried to determine the most straightforward way of simultaneously determining the transmission and DLG in the shortest time. We measured all data at 5cm depth using a Varian VitalBeam LINAC, newly installed at TMSS Cancer Center, Bogura, Bangladesh. We used three significant pieces of equipment in our experiment: an integrated Electronics Portal Imaging Device (EPID), a solid water phantom and a farmer-type ion chamber (Model: IBA FC65-P). The Eclipse™ TPS was also used to make the QA plan and to analyze the images.
