Received: 2 October 2020
Accepted: 4 January 2021
First Online: 5 February 2021
Ethics approval and consent to participate
: All procedures involving human participants were conducted in accordance with the ethical standards of the institutional research committee at the Koseiren Sanjo General Hospital (IRB approval number 201910) and with the 1964 Declaration of Helsinki and its later amendments. Written informed consent was obtained from all patients or from their relatives where the patients had died before the study.
: Not applicable.
: The authors declare that they have no competing interests.