Funding for this research was provided by:
Science and Technology Commission of the Shanghai Municipality (14411961800)
National Health and Family Planning Commission of Shanghai (20144Y0264)
Received: 25 January 2018
Accepted: 29 January 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: The Institutional Review Board at Eye, Ear, Nose, and Throat Hospital of Fudan University approved this study.
: Not applicable. Images in our article are entirely unidentifiable and there are no details on individuals reported within the manuscript.
: The authors have declared that no competing interests exist.
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