1. Department of Neurosurgery, Haseki Research and Training Hospital, Aksaray Street, Fatih, 34130 Istanbul, Turkey
2. Department of Neurosurgery, Özel Osm Ortadoğu Hospital, 63100 Şanlıurfa, Turkey
3. Department of Neurosurgery, Afyon Kocatepe University Hospital, 03103 Afyonkarahisar, Turkey