ESTRO 2023 - Abstract Book

S1450

Digital Posters

ESTRO 2023

Results Only materials 1-4 have CT number, T1 and T2 relaxation times that fell within the range of the brain’s grey and white matter. Figure 1 shows the mean of CT number, T1 and T2 relaxation times, and the standard deviation for each material over time and after radiation exposure. Regarding the stability of materials over time, all the observed change for all four materials was within two standard deviations (of the pixel values) which indicates the materials are stable over this timeframe. As for the stability after radiation exposure, all the observed changes were within two standard deviations (of the pixel values) except for the T2 relaxation time for material No. 1, and the change that occurred after exposure to 10 Gy in material No. 3. Further investigation will be done to investigate the reasons for these changes.