Article History
Received: 2 January 2019
Accepted: 17 May 2019
First Online: 24 May 2019
Ethics approval and consent to participate
: The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national and institutional guidelines on human experimentation (Human Research Committee of Shanghai Eye & ENT hospital) and with the Helsinki Declaration of 1975, as revised in 2008. Written informed consent was obtained from all patients.
: Not applicable.
: The authors declare that they have no competing interests.
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