1. Department of Radiology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun 519-763, Korea.
2. Department of Radiology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju 501-757, Korea.
3. Center for Aging and Geriatrics, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju 501-757, Korea.
4. Department of Obstetrics and Gynecology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun 519-763, Korea.