Received: 13 May 2020
Accepted: 2 October 2020
First Online: 9 October 2020
Ethics approval and consent to participate
: The Institutional Review Board of the Seoul National University Hospital approved the procedure of reviewing medical records, and obtaining consent was waived because all data analyzed in this paper are anonymous (H-1906-155-1045).
: Not applicable.
: The authors have no conflicts of interest to disclose.