The purpose of the research study is to test new methods that could improve diagnosis and assessment of brain tumors. One of these methods is a new MR (magnetic resonance) imaging technique called magnetic resonance fingerprinting (MRF), which allows for rapidly scanning the patient and provides quantitative information on tumor tissue. The investigators will compare the data gathered from MR Fingerprinting with other imaging tests, clinical information, treatment details and biopsy results to evaluate the accuracy of this new technique.

The primary objective of this study is to 1) evaluate the utility of quantitative MRI imaging including 3D-MRF in differentiating among different brain tumors and differentiating recurrent brain tumor (TR) from treatment effects

Secondary objectives include evaluating the correlation between quantitative MRI imaging with histopathological characteristics and genetic markers in pre-therapy setting and with treatment response and clinical outcomes in post treatment setting.

GROUP 1: All patients with newly diagnosed intra-axial brain neoplasms undergo volumetric MRI study with contrast for surgical planning or clinical diagnosis. Diffusion, diffusion tensor imaging and perfusion imaging are often performed as a part of standard clinical imaging. In addition to these acquisitions, the research 3D-MRF acquisition through the entire tumor will be acquired. The imaging parameters will be correlated individually and in combination with biopsy/ resection outcomes.

GROUP 2: All patients with brain tumors who present at post therapy follow up with imaging progression undergo serial imaging as a part of clinical care. The research 3D-MRF acquisitions will be added to these clinical scans. All the quantitative parameters will be evaluated individually and in combination to differentiate post treatment changes from tumor recurrence.

Inclusion Criteria:

• Diagnosis of intra-axial brain tumor at initial diagnosis or patients with known treated brain tumors on follow-up with concern for imaging progression
• Ability to understand and the willingness to sign a written informed consent document, or, in cases where the patient may have cognitive impairment, consent by a legal authorized representative or power of attorney
• Patients with brain metastases undergoing partial brain radiation (gamma knife or SRS) with ability to undergo research scan at baseline, 1 month and , 3 months, and 6 months

Exclusion Criteria:

• Patients with ferromagnetic or otherwise non-MRI compatible aneurysm clips.
• The presence of an implanted pacemaker or implanted defibrillator device.
• Patients with contraindications for MRI due to embedded foreign metallic objects. Bullets, shrapnel, metalwork fragments, or other metallic material adds unnecessary risk to the patient.
• Pregnancy. Regular clinical practice already excludes pregnant patients from gadolinium contrast.
• Implanted medical device not described above that is not MRI-compatible.
• Known history of severe claustrophobia.
• Prisoners and members of other vulnerable populations will be excluded from this study. The subject selection population will not regularly include prisoners and other vulnerable population members as these populations will not provide any additional unique information to or uniquely benefit from the study. Non-English speaking population will be excluded from the study due to lack of sufficient resources to pay for translator and interpreter services.
• Minors will be excluded.