1Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Republic of Korea, 2Kyung Hee University Hospital, Seoul, Republic of Korea, 3Univeristy Industry Cooperation, Kyung Hee University, Seoul, Republic of Korea, 4Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea, 5Neurosurgery, Ewha Womans University School of Medicine, Mokdong Hospital, Seoul, Republic of Korea, 6College of Medicine, Konyang University Hospital, Konyang University Myunggok Medical Research Institute, Daejeon, Republic of Korea