RecruitingProcedureSpectroscopic MRI Guided Proton Therapy in Assessing Metabolic Change in Pediatric Patients With Brain TumorsThis trial studies how well spectroscopic magnetic resonance imaging (MRI) guided proton therapy works in assessing metabolic change in pediatric patients with brain tumors. The non-invasive imaging, such as spectroscopic MRI may help to map the differences in tumor metabolism compared to healthy tissue without injection of any contrast agent.