1. Department of Neurosurgery, Konya Training and Research Hospital, Konya, Turkey
2. Department of Neurosurgery, Baskent University, Ankara, Turkey
3. Department of Interventional Radiology, Baskent University, Ankara, Turkey
4. Department of Anesthesiology, Baskent University, Ankara, Turkey
5. Department of Anesthesiology, Konya Training and Research Hospital, Konya, Turkey