1 Diagnostic Imaging and Interventional Neuroradiology Unit, Neurosurgery Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Via Celoria, Milano, Italy.
2 Cerebrovascular Diseases Unit, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Via Celoria, Milano, Italy.