Received: 29 January 2020
Accepted: 12 May 2020
First Online: 24 May 2020
Ethics approval and consent to participate
: This study is approved by the IRB of Beijing Chao-Yang Hospital and Beijing Luhe Hospital. Written informed consent was obtained from all participants (where participants are children under 16 years old, from their parent or guardian).
: Written informed consent was obtained from all participants for their data to be used for research and publication. Written informed consent for participation in the study was obtained where participants are children (under 16 years old) from their parent or guardian. We confirm that the patients, and in the case of minors their parents/guardians, provided written informed consent for the publication of potentially identifying images and clinical details.
: The authors declare that no conflicts of interests.