1. Neurosurgery Clinic, General Hospital “Asklepieio”, 16673 Athens, Greece
2. 2nd Department of Radiology, University General Hospital “ATTIKON”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
3. Orthopaedic Surgery & Traumatology, University General Hospital “ATTIKON”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece