18F-FDG PET-MRI for Planning and Follow-Up of Patients With Spine Tumors Treated With Spine Stereotactic Radiosurgery

Inclusion Criteria: * Consent to imaging study * Presence of at least 1 lumbar vertebral body bone metastasis \> 1 cm in shortest diameter and smaller than 75% of the vertebral body cross sectional area. Metastasis may be determined by pathology, or imaging appearance. * Eligibility to receive SSRS (determined by treating radiation oncologists) * Plan for single-fraction SSRS * Standard-of-care spine MRI within 8 weeks of radiation therapy * Ability to understand and willingness to sign a written informed consent document * Non-English speaking participants will be included. Verbal Translation Preparative Sheet (VTPS) short form will be utilized in consenting non-English speaking participants. Exclusion Criteria: * Absolute or relative contra-indication to MRI, including presence of a pacemaker that requires involvement of cardiology/anesthesiology during the scan * Prior directed radiation to the involved segment * Contra-indication to gadolinium based contrast agents (e.g., allergy, pregnancy) * Individuals younger than 18 years * Hardware at the treatment level or hardware affecting visualization of the involved level on MRI * Pregnant women