1. Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
2. Department of Radiology, Armed Forces Yangju Hospital, Yangju, Korea.
3. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
4. Department of Radiology, Gyeongsang National University Changwon Hospital, Changwon, Korea.
5. Department of Radiology, Chonnam National University Hospital, Gwangju, Korea.
6. Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea.
7. Division of Pediatric Neurosurgery, Seoul National University Children’s Hospital, Seoul, Korea.
8. Department of Emergency Medicine, Armed Forces Yangju Hospital, Yangju, Korea.
9. Army Aviation Operations Command, Icheon, Korea.