Fig. 3

Predicted response to radiation therapy for a representative animal receiving 40 Gy. Results are shown over the entire tumor volume for a representative animal receiving a single fraction of 40 Gy. (The results are presented in an identical fashion to Fig. 2) The RT1 model is capable of predicting the spatial heterogeneity (the development of necrosis) observed in the measured \( {\phi}_T\left(\overline{x},t\right) \). The RT2 model overestimates the tumor volume at both prediction time points. For \( {\phi}_V\left(\overline{x},t\right) \), the RT1 model was able to predict areas of low \( {\phi}_V\left(\overline{x},t\right) \) in the interior and areas of high \( {\phi}_V\left(\overline{x},t\right) \) at the periphery of the tumor. The model, however, predicts a lower \( {\phi}_V\left(\overline{x},t\right) \) at the interior of the tumor in comparison to the measurement. The fused images demonstrate a high level of agreement in the tumor (white regions), as well as areas where the model fails to predict future tumor growth extent (pink regions)