1. Department of Neurosurgery, Bülent Ecevit University Faculty of Medicine, Zonguldak, Turkey
2. Department of Anesthesiology and Reanimation, Bülent Ecevit University Faculty of Medicine, Zonguldak, Turkey
3. Department of Pathology, Hitit University Faculty of Medicine, Çorum, Turkey
4. Department of Biochemistry, Bülent Ecevit University Faculty of Medicine, Zonguldak, Turkey
5. Department of Radiation Oncology, Bülent Ecevit University Faculty of Medicine, Zonguldak, Turkey
6. Department of Biostatistics, Bülent Ecevit University Faculty of Medicine, Zonguldak, Turkey