TENS of Auricular Vagal Nerve for Radiation Necrosis

This is a multi-center, randomized, blinded trial evaluating the effect of transcutaneous auricular vagal nerve stimulator (taVNS) on radiation necrosis-related cerebral edema. In this study, consenting and eligible patients will be assigned to one of two arms: treatment (Arm 1) or sham (Arm 2). Patients in both arms will have imaging performed and tissue and blood collected for assessment of changes in area of contrast enhancement and cerebral edema, inflammatory markers, and markers of blood-brain barrier permeability.