Received: 29 April 2019
Accepted: 25 July 2019
First Online: 9 August 2019
Ethics approval and consent to participate
: The retrospective study was approved by the Ethics Committee of Peking University People’s Hospital (Grant Number 2017PHB181–01) and informed consent was waived due to the retrospective nature of this study.
: All the images and videos used in this article were completed following obtaining a written informed consent for publication from each patient.
: The authors declare that they have no competing interests.