Radiation associated imaging changes. Panels A and B show typical radiation changes that are apparent on chest CT approximately 3–9 months following SBRT. Images on the left show pre-treatment tumor and images on the right show post-SBRT changes. Both axial and coronal planes are provided. The imaging changes depicted above are considered grade 1 radiation pneumonitis by the CTCAE v4.o criteria if they are not associated with clinical symptomatology.