1. From the Departments of Radiology, Hacettepe University, School of Medicine, Ankara, Turkey

2. Departments of Radiology, Hacettepe University School of Medicine, Ankara, Turkey

3. From the Departments of Neurosurgery Hacettepe University, School of Medicine, Ankara, Turkey

4. From the Departments of Biostatistics, Hacettepe University, School of Medicine, Ankara, Turkey