Alexandros Andreou MD PhD, Director, Dept. of Neurosurgery and Interventional Neuroradiology, Hygeia Hospital, Athens, Greece Prof. Gerhard Bavinzski, Dept. of Neurosurgery, University of Vienna, Austria Prof. Kostas Fountas,Dept. of Neurosurgery, Un. Of Thessaly, Larisa, Greece Aikaterini Vlastou MD, Director, Dept. of Plastic Surgery, Hygeia Hospital Athens, Greece Prof. Ioannis Patsalas, Dept. of Neurosurgery, University of Thessaloniki, Greece Akis Frantzoglou MD, Director, Dept. of Neurosurgery, Nikaia Hospital, Athens, Greece Phillip Dodier MD, Dept. of Neurosurgery, University of Vienna, Austria Vladimir Papic MD, Ass. Professor, Dept. of Neurosurgery, University of Novi Sad, Serbia Triantafyllos Triantafyllou MD, Dept. of Neurosurgery, Lamia Hospital, Greece Sotiris Plakas MD, Dept. of Neurosurgery and Interventional Neuroradiology, Hygeia Hospital, Athens, Greece Christos Chrysikopoulos MD, Dept. of Neurosurgery and Interventional Neuroradiology, Hygeia Hospital, Athens, Greece Vasiliki Xenaki MD, Dept. of Neurosurgery, Nikaia Hospital, Athens, Greece Lampis Stavrinou MD, Dept. of Neurosurgery, Attikon Hospital, Athens, Greece