[1] Duatepe Hosp, Minist Hlth, Neurosurg Clin, Ankara, Turkey
[2] Beyazit Training & Res Hosp, Minist Hlth Diskapi Yildirim, Neurosurg Clin 2, Ankara, Turkey
[3] Ankara Numune Training & Res Hosp, Minist Hlth, Neurosurg Clin 2, Ankara, Turkey
[4] Ankara Univ, Deontol Dept, TR-06100 Ankara, Turkey