Wiener Filter Used in the EBT2 Film for Radiation Therapy

EBT2 film has been widely used in the dosimetry application of radiation therapy with lots of benefits especially its self-development, water equivalent, energy independent and high spatial resolution. However, the higher inhomogeneity between the pixels of EBT2 image, needed to be averaged out according to the traditional method, but it could sacrifice the spatial resolution. The Wiener filter technique was introduced in this paper. The EBT2 film was calibrated by using the PDD method and the film calculate doses were compared with the measurement doses by the edge detector with the water phantom. The results demonstrate that the Wiener filter technique has higher accuracy than the traditional method and it would not sacrifice the high spatial resolution of EBT2 film. This method can also be applied to all the quality assurances of treatment planning of radiationtherapy by using EBT2 film.