Thirty-six children, aged 6 to 17, with a history of posterior fossa tumor (17 treated with surgery; 19 with SC-CRT) underwent neuroimaging and neuropsychological assessment at least 1 year post-treatment, along with 15 healthy sibling controls. All had magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) and neuropsychological evaluation done (n=51). The putamen, thalamus, and hippocampus were manually segmented on each participant’s MRI and in the radiation treatment group, the radiation dose for each structure was calculated.