Figure 3

Flow chart of dose reconstruction on CT images by Octavius arrays. The 3D dose distribution within the phantom was calculated using percent depth dose data at different beam fields (fields of 4 × 4 cm2, 10 × 10 cm2, and 26 × 26 cm2 are mandatory, others may slightly contribute to the accuracy) by linear interpolation. Based on this, the DVH on the patients’ anatomical structures was calculated. PDDs = percent depth doses; TPRs = tissue phantom ratios.