Investigation of polymer BANG gel dosimetry using X-ray computed tomographic imaging

The purpose of this work is to determine the optimal X-ray computed tomography (CT) imaging parameter settings for polymer BANG gel dosimetry. Several homemade polymer BANG gel samples were manufactured following the formulation demonstrated by Maryanski et al in 1994. The protocol for CT-based polymer BANG gel dosimetry was determined experimentally. Our preliminary results indicate that the optimal CT imaging parameter settings for polymer BANG gel dosimetry are: tube potential = 120 kVp, tube current exposure = 400 mAs, slice thickness = 5 mm, and images acquired per scan position = 20. The appropriate CT imaging time to be 2 days after irradiation observed form reproducibility analysis. A good linearity was performed between CT numbers with irradiation doses ranging from 2-14 Gy. The CT images of polymer BANG gel dosimetry acquired when following our protocol can accurately extract dose information in a clinical radiotherapy environment.