1 National Neurosurgical Centre, Beaumont Hospital, Dublin, Ireland; Department of Neurosurgery, Royal College of Surgeons in Ireland, Dublin, Ireland.
2 National Neurosurgical Centre, Beaumont Hospital, Dublin, Ireland; Department of Neuroradiology, Beaumont Hospital, Dublin, Ireland.
3 National Neurosurgical Centre, Beaumont Hospital, Dublin, Ireland; Department of Neurosurgery, Royal College of Surgeons in Ireland, Dublin, Ireland; Department of Academic Neurology, Trinity College Dublin, Dublin, Ireland.