1. Department of Radiology, Hacettepe University, School of Medicine, Ankara, Turkey, 06100.
2. Present address: Department of Radiology, Zonguldak Ataturk State Hospital, Zonguldak, Turkey.
3. Department of Radiology, Artvin State Hospital, Artvin, Turkey.
4. Department of Radiology, Koc University, Istanbul, Turkey.