1 Division of Neurointerventional Radiology (Kühn, Singh), Department of Radiology, University of Massachusetts Medical Center; Department of Neurological Surgery (McGillicuddy), University of Massachusetts Chan Medical School, Worcester, Mass.
2 Division of Neurointerventional Radiology (Kühn, Singh), Department of Radiology, University of Massachusetts Medical Center; Department of Neurological Surgery (McGillicuddy), University of Massachusetts Chan Medical School, Worcester, Mass. jasmeet.singh@umassmemorial.org.