Inclusion Criteria:

• Male or female, aged 18 to 80.
• Willingness and medical ability to comply with study procedures.

Patients in Aim 2

• Evidence of normal kidney function (eGFR of > 60 ml/min/1.72 m^2) as assessed by laboratory testing (or eGFR immediately prior to MRI scan if laboratory testing was acquired more than 60 days before time of enrollment).
• Ability to understand the purpose and risks of the study and provide signed and dated informed consent and authorization to use PHI in accordance with regulations. Subjects’ Legally Authorized Representatives can sign and date informed consent when applicable. In addition, patients must meet the following inclusion criteria:

Patients in Aim 2

• Confirmed diagnosis of brain neoplasm.

Patients in Aim 3

• Confirmed diagnosis of HGG. 
• Will be receiving Bevacizumab therapy.

Patients in Aim 2 and 3

• At least 1 enhancing brain lesion > 5 mm.

Exclusion Criteria:

• Pregnant women or women currently breastfeeding.
• History of claustrophobia or panic that cannot be adequately controlled.
• Physical limitation related to fitting in the bore of the magnet, including large body habitus or inability to lay supine in the magnet because of orthopnea.
• History of allergic reaction to Gd-based contrast agent.
• Contraindications to having a brain MRI, for reasons such as presence of a pacemaker, epicardia pacemaker wires, MRI-incompatible cardiac valve prostheses, MRIincompatible vascular clip, MRI-incompatible cochlear implant, spinal nerve simulator, implanted infusion pump, metallic fragments in the eyes/orbits or in the vicinity of the brain or major neurovascular structures of the body, an employment history which involves exposure to welding, or shrapnel any place in their body.

Patients in Aims 2

• Subjects with acute kidney injury or renal insufficiency (eGFR of < 20 ml/min/1.73 m^2) as assessed within the prior 12 months as they are at increased risk of Nephrogenic Systemic Fibrosis (NSF) following administration of Gd-based MRI contrast agents.
• Other unspecified reasons that, in the opinion of the Investigator, make the subject unsuitable for enrollment or unable to comply with study procedures or assessments.
• In addition, healthy controls will be excluded from entry into the study if they meet the following criteria:
  • Clinical history of neurological symptoms or disorders.