1. Department of Anatomy, Brain Research Institute, Chungnam National University School of Medicine, Daejeon 301-747, Korea
2. Department of Pediatrics, Chungnam National University Hospital, Daejeon 301-721, Korea
3. Department of Plastic Surgery, Chungnam National University Hospital, Daejeon 301-721, Korea
4. Department of Anesthesia and Pain Medicine, Chungnam National University Hospital, Daejeon 301-721, Korea