Article History
Received: 7 February 2018
Accepted: 8 June 2018
First Online: 26 June 2018
Ethics approval and consent to participate
: The study was performed in accordance with the principles of the Declaration of Helsinki, 1995 (revised in Edinburgh in 2000). This study was approved by the medical ethics committee of Peking University People’s Hospital. The parents or legal guardians of the patients provided consent for participation in the study on behalf of the underage patients, and written informed consent was obtained.
: Written consent for publication of the images was obtained from the patients’ guardians.
: The authors declare that they have no competing interests.
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