Inclusion Criteria:

- Signed Informed Consent Form

- Age equal or greater than 18 years

- Histologically confirmed high grade glioma

- Radiographic demonstration of disease progression following prior therapy of
temozolomide + radiation

- Patient scheduled for bevacizumab + standard IV chemotherapy therapy

- Bi-dimensionally measurable disease on gadolinium enhanced T1 weighted MR scans

- An interval of at least 4 weeks since prior surgical resection

- Patients must be off corticosteroids at least 1 week before the start of the study

- Karnofsky performance status greater than or equal to 70

- Life expectancy greater than 12 weeks

- Ability to comply with study and follow-up procedures

Exclusion Criteria:

- Pregnant or nursing females

- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, or psychiatric illness/social situations that would limit compliance with
study requirements

- Known liver function insufficiency, stage IV or V renal insufficiency

- Disease and Treatment History: Prior treatment with bevacizumab, or another VEGF or
VEGFR-targeted agent; Need for urgent palliative intervention for primary disease
(e.g., impending herniation

- Bevacizumab Exclusion Criteria: History of hypertensive encephalopathy; New York
Heart Association (NYHA) Grade II or greater CHF; History of myocardial infarction or
unstable angina within 6 months prior to start of the study; History of stroke or
transient ischemic attack within 6 months prior to study enrollment; Significant
vascular disease (e.g., aortic aneurysm, aortic dissection) or recent peripheral
arterial thrombosis within 6 months prior to start of the study; Evidence of bleeding
diathesis or coagulopathy; on therapeutic anti-coagulants.

- Subjects unable to undergo an MRI with contrast

- Ferumoxytol Exclusion Criteria: History of allergic reactions attributed to compounds
of similar chemical or biologic composition to ferumoxytol: parenteral iron,
parenteral dextran, parenteral iron-dextran, or parenteral iron-polysaccharide
preparations (Ferumoxytol Investigator's Drug Brochure, 2005). Patients with
significant drug or other allergies or autoimmune diseases may be enrolled at the
Investigator's discretion

- Subjects with known or suspected iron overload (genetic hemochromatosis or history of
multiple transfusions).Patients with transferrin saturation greater than 60%

- Inability or unwillingness to undergo the complete series of imaging sessions.
Inability or unwillingness to return to the neuro-oncology clinic at OHSU for the one
month follow-up