Background: Fractionated radiation therapy (RT) is a mainstay in the treatment of primary and metastatic brain tumors. However, RT to the brain is associated with an inevitable decline in neurocognitive function in up to 90% of patients who survive more than 6 months after irradiation. Radiation to the brain results in an inevitable decline in neurocognitive function, mediated by tissue injury to white matter, cortex and subcortical areas. With quantitative magnetic resonance imaging (MRI) techniques, investigators can directly and non-invasively measure such changes.~Objective/Hypothesis:~The purpose of this study is to examine radiation-induced imaging changes in normal brain tissue over time in primary brain tumor patients, and correlate these with neurocognitive outcomes. The overarching goal is to better identify sensitive brain regions so that future radiation techniques can be optimally designed to mitigate collateral damage.~Specific Aims:~To identify microstructural changes in subcortical white matter, hippocampus, and cortex associated with quantified regional exposure to fractionated brain radiotherapy using advanced quantitative neuroimaging imaging~To identify changes in neurocognitive functioning in primary brain tumor patients after brain radiotherapy~Study Design:~The investigators will prospectively enroll primary brain tumor patients undergoing fractionated partial brain radiation therapy. Patients will undergo volumetric and diffusion brain MRI (per clinical standard-of-care) and a neurocognitive battery of tests at baseline (pre-treatment), 3 months, 6 months, and 12 months post-treatment. Clinical data including age, gender, educational status, tumor size and histology, steroid use, antiepileptic drug use and chemotherapy will be recorded.
In this proposal, the investigators introduce a novel, translational study to prospectively examine primary brain tumor patients undergoing fractionated radiation therapy to the brain. Quantitative neuroimaging, radiation dose information, and directed neurocognitive testing will be acquired through this study to improve understanding of cognitive changes associated with radiation dosage to non-targeted tissue, and will provide the basis for evidence-based cognitive- sparing brain radiotherapy.