This is a study to determine if Magnetic Resonance Imaging (MRI) techniques can detect early changes in white matter (in the brain) and the blood-brain barrier resulting from radiation therapy.

Patients will be assigned to one of two groups based on the type of radiation they will be receiving: whole brain irradiation or partial brain irradiation. Patients will undergo Magnetic Resonance Imaging (MRI) assessments, neurocognitive testing (Quality of Life and Neuropsychological assessments), and clinical evaluation.

Inclusion Criteria:

• Patients receiving partial brain irradiation for malignant or benign brain tumors (including low-grade gliomas, high-grade gliomas, malignant meningioma, pituitary adenomas, supratentorial meningioma, or craniopharyngiomas); or patients receiving whole brain irradiation for brain metastases.
• Patients must be 18 years of age or older
• Patients must sign a study specific consent form approved by the Institutional Review Board (IRB) of the University of Michigan prior to study entry.
• Patients must have a neurological function class 1 or 2 with a Karnofsky performance status (a scoring system used to quantify general well being and quality of life on a scale of 100 to 0) of greater than or equal to 70.
• Patients must have an expected life expectancy of greater than 6 months.

Exclusion Criteria:

• Patients with a history of major medical illness or psychiatric impairment which, in the investigator's opinion, will prevent administration of the protocol.
• Patients who have had prior external beam irradiation to the brain or head/neck area that will lead to overlap of the radiation field.
• Patients should have no contraindications to having a contrast enhanced Magnetic Resonance Imaging (MRI) scan.
• Prisoners are excluded.
• Pregnant women are excluded.

Patients receiving partial or whole brain radiation therapy