1 Department of Radiology, Mayo Clinic, Rochester, MN, USA; Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA.
2 Department of Radiology, Mayo Clinic, Rochester, MN, USA; Department of Physiology, CURAM-SFI Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland.
3 Department of Physiology, CURAM-SFI Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland.
4 Department of Radiology, Mayo Clinic, Rochester, MN, USA.
5 Department of Neurology, Mayo Clinic, Rochester, MN, USA.
6 Department of Radiology, Mayo Clinic, Rochester, MN, USA; Department of Neurosurgery, Mayo Clinic, Rochester, MN, USA. Electronic address: [email protected].