1 Department of Neurosurgery and Neuroscience Institute, Geisinger Health System and Geisinger Commonwealth School of Medicine, Wilkes-Barre, Pennsylvania, USA; Research Institute of Neurointervention, Paracelsus Medical University, Salzburg, Austria. Electronic address: cmschirmer@gmail.com.
2 Division of Neurosurgery, Southern Illinois University School of Medicine, Springfield, Illinois, USA.
3 Department of Neurosurgery, Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA.