1. Department of Occupational and Environmental Medicine, Chonnam National University (CNU) Medical School and CNU Hwasun Hospital, Hwasun, Republic of Korea
2. Institute of Occupational and Environmental Health, Korea Workers’ Compensation & Welfare Service, Incheon, Republic of Korea
3. Department of Occupational and Environmental Medicine, Gwangyang Sarang General Hospital, Gwangyang, Republic of Korea
4. Department of Radiology, CNU Medical School and CNU Hwasun Hospital, Republic of Korea