Spectroscopic MRI Guided Proton Therapy in Assessing Metabolic Change in Pediatric Patients With Brain Tumors

This study uses specialized brain MRI (called spectroscopic MRI) alongside proton therapy — a precise form of radiation — to track chemical changes in the brains of children with high-grade brain tumors during and after treatment. The goal is to better understand how treatment is working at a molecular level. **You may be eligible if...** - You have been diagnosed with a high-grade glioma (grade 3 or 4 brain tumor), confirmed or strongly suspected by imaging - Your tumor is located in the upper part of the brain (supratentorial) - You are recommended to receive definitive radiation therapy - You are able to undergo MRI scans - People of all genders, races, and ethnicities are welcome **You may NOT be eligible if...** - You have a pacemaker, certain metal implants, cochlear implants, or other devices that make MRI unsafe - Your tumor turns out to be low-grade or benign after biopsy - You have a serious illness that prevents you from tolerating MRI Talk to your doctor to see if this trial is right for you.