Received: 15 August 2017
Accepted: 14 February 2018
First Online: 20 February 2018
Ethics approval and consent to participate
: This study followed the tenets of the Declaration of Helsinki and was approved by the ethics committee of the Eye and ENT Hospital of Fudan University. Informed consent was obtained from all participants.
: Not Applicable.
: The authors declare that they have no competing interests.
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