Ferumoxytol in Magnetic Resonance Imaging of Pediatric Patients With Brain Tumors

Inclusion Criteria: * Subjects with a presumed diagnosis of brain tumor (based on imaging) or a confirmed brain tumor (based on pathology) before or after any oncologic treatment (surgery/chemotherapy/radiation) * All subjects, or their legal guardians, must sign a written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization in accordance with institutional guidelines * Subjects with a calculated glomerular filtration rate (GFR) \> 60 mL/min/1.73 m\^2 * Sexually active women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; surgical intervention i.e. tubal ligation or vasectomy; post-menopausal \> 6 months or abstinence) for at least two months after each cycle of the study; should a female become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately Exclusion Criteria: * Subjects with clinically significant signs of uncal herniation, such as acute pupillary enlargement, rapidly developing motor changes (over hours), or rapidly decreasing level of consciousness, are not eligible * Subjects with known allergic or hypersensitivity reactions to parenteral iron, parenteral dextran, parenteral iron-dextran, or parenteral iron-polysaccharide preparations (Ferumoxytol Investigator's Drug Brochure, 2009); subjects with significant drug or other allergies or autoimmune diseases may be enrolled at the investigator's discretion * Subjects who are pregnant or lactating or who suspect they might be pregnant * Subjects who have a contraindication for 3Tesla (3T) MRI: metal in their bodies (a cardiac pacemaker or other incompatible device), are severely agitated, or have an allergy to gadolinium containing contrast material * Subjects with known iron overload (genetic hemochromatosis); in subjects with a family history of hemochromatosis, hemochromatosis must be ruled out prior to study entry with normal values of the following blood tests: transferrin saturation (TS) test and serum ferritin (SF) test; all associated costs will be paid by the study * Subject who have received ferumoxytol within 4 weeks of study entry