1. Department of Radiology, S-Jungang Hospital, Jeju, Republic of Korea.
2. Department of Neurosurgery, Donghae Dongin Hospital, Donghae, Republic of Korea.
3. Department of Neurology, Gangneung Asan Hospital, College of Medicine, University of Ulsan, Gangneung, Republic of Korea.
4. Department of Neurosurgery, Gangneung Asan Hospital, College of Medicine, University of Ulsan, Gangneung, Republic of Korea.