1. Department of Dermatology Beijing Tsinghua Changgung Hospital Tsinghua University Beijing 102218 China
2. Department of Plastic Surgery Meitan General Hospital Beijing 100028 China
3. Department of Biomedical Engineering School of Medicine Tsinghua University Beijing 100084 China
4. Department of Hepatobiliary Surgery Beijing Tsinghua Changgung Hospital Tsinghua University Beijing 102218 China
5. Department of Plastic, Reconstructive and Aesthetic Surgery Nippon Medical School Tokyo 113‐8603 Japan