A, C, E: Evolution of mean RIL grade in XRT (blue lines) and PRT (orange lines) groups at global (A), ipsilesional (C), and contralesional (E) hemispheric levels. In both groups, global and hemispheric RIL grade increases significantly from baseline up through 3-years post-radiotherapy. The PRT group exhibits slightly greater average RIL grade across all time points (finding only significant at baseline). B, D, F: Analysis of RIL injury dynamics (mean % change between 1- and 3-years post-radiotherapy) in XRT (blue lines) and PRT (orange lines) groups at global (B), ipsilesional (D), and contralesional (F) hemispheric levels, demonstrating an association of XRT with significantly greater RIL injury dynamics in the contralesional hemisphere. Mean and SEM are given.