Inclusion Criteria:
* Written informed consent will be obtained from each participants including healthy volunteers.
* Healthy volunteers will not have contra-indications to MR scanning, but will otherwise not be subject to other selection criteria.
* All patients will be enrolled in study # 2011-0370, the Stereotactic RadPath trial
* Patient is \>18 years old, agrees to participate in the clinical study and to complete all required visits and evaluations. The pediatric population has a different disease profile from the glioma patients we hope to recruit. To reduce heterogeneity in the patient population we will not consider patients younger than 18 for this study.
* Patient is a candidate for cerebral tumor resection with lesion suspected to be or previously biopsy proven to be a primary brain tumor.
* Patient is able to understand and give consent to participation in the study.
* Patient agrees to undergo, prior to the procedure, magnetic resonance imaging (MRI, within 14 days and preferably with 3 days of the planned procedure) with perfusion, diffusion and spectroscopic imaging.
* Patient has a GFR \> 60. In patients with moderate renal failure (GFR 30-60), an alternate injection with 2 times half-dose multihance (gadobenate dimeglumine) or gadovist (gadobutrol) will be considered, if a contrast exam is deemed clinically necessary.
* Specifically for this Study: Patient is willing to give signed informed consent for C13-Pyruvate MR Spectroscopy.
Exclusion Criteria:
* Healthy volunteers will be screened using same process but will otherwise not be subject to other selection criteria.
* The patient is found to have unfavorable anatomy to indicate that stereotactic biopsy could not be safely performed.
* Pacemakers, electronic stimulation, metallic foreign bodies and devices and/or other conditions that are not MR safe, which include but are not limited to: • electronically, magnetically, and mechanically activated implants • ferromagnetic or electronically operated active devices like automatic cardioverter defibrillators and cardiac pacemakers • metallic splinters in the eye • ferromagnetic hemostatic clips in the central nervous system (CNS) or body • cochlear implants • other pacemakers, e.g., for the carotid sinus • insulin pumps and nerve stimulators • non-MR safe lead wires • prosthetic heart valves (if dehiscence is suspected) • non-ferromagnetic stapedial implants • pregnancy • claustrophobia that does not readily respond to oral medication
* Prior brain tumor treatment, including surgical resection, radiation therapy or chemotherapy for a primary brain neoplasm. Previous biopsy will not disqualify the patient from participation. Remote history (\> 6month) of non-CNS malignancy in remission, without evidence of current/ prior brain metastasis, will also not disqualify patient from participating.
* History of cardiac arrhythmia
