Received: 11 December 2020
Accepted: 11 May 2021
First Online: 21 May 2021
: This study was approved by the Ethics Committee of Faculty of Medicine, Toho University (A19039_27128_25095_25047). This study was conducted based on patient data from 2005 to 2019. Because this study was retrospective and we utilized existing information of all patients, we did not require permission to access and use the individual data/video files and we did not obtain individual consent from all patients according to Ethical Guidelines for Medical and Health Research Involving Human Subjects of the Ministry of Health, Labour and Welfare in Japan (ExternalRef removed- Daijinkanboukouseikagakuka/0000080278.pdf). The presented study design was accepted by the ethics committee on the condition that.
: Not applicable.
: The authors declare that they have no competing interests.