Inclusion Criteria:  AIM 1: Healthy volunteers with no evidence of brain tumors or neurologic disease AIM 1: Age 18+ AIM 2: Newly diagnosed or recurrent suspected or confirmed glioma (low or high grade) AIM 2: 10 IDH mutant and 10 IDH wild type gliomas AIM 2: Clinically indicated for resective surgery or biopsy AIM 2: Age 18+ AIM 2: Tumor size > 1x1x1 cm (measurable) AIM 3: Recurrent glioma enrolled in an immunotherapy trial or clinically indicated to receive immunotherapy including anti-PD1 AIM 3: Age 18+  Exclusion Criteria:  AIM 1: Cannot safely perform an MRI AIM 1: Age < 18 AIM 2: Cannot safely perform an MRI or use of MRI contrast agents AIM 2: Age < 18 AIM 3: Cannot safely perform an MRI or use of MRI contrast agents AIM 3: Age < 18