Hyperpolarized Carbon C 13 Pyruvate Magnetic Resonance Spectroscopic Imaging in Detecting Lactate and Bicarbonate in Participants With Central Nervous System Tumors

Inclusion Criteria:

   - Patients with a known diagnosis of central nervous system (CNS) malignancy, including
   metastases, with known enhancement on magnetic resonance (MR) who are otherwise
   eligible to undergo MRI

   - Glomerular filtration rate (GFR) > 30 ml/min

   - No allergy to gadolinium

   - Ability to understand and the willingness to sign a written informed consent document

Exclusion Criteria:

   - Refusal to have an IV placed for injection

   - Acute major illness (e.g., unstable angina, etc.) or other condition that makes
   participation unsafe, per the investigator?s judgement

   - Total bilirubin > 1.5 x upper limit of normal (ULN)

   - Aspartate aminotransferase (AST)/alanine aminotransferase (ALT) > 2.5 x ULN

   - Gamma-glutamyltransferase (GGT) > 2.5 x ULN

   - Pregnant or breast-feeding

   - Cardiovascular risk, including:

      - Poorly controlled hypertension, defined as either systolic > 170 or diastolic >
      110

      - Congestive heart failure

      - Myocardial infarction within the past year

      - QT prolongation, defined as pretreatment corrected QT interval (QTc) > 440 msec
      in males or > 460 msec in females