Asakura, Keisuke
Yoshida, Yukihiro
Sakurai, Hiroyuki
Nakagawa, Kazuo
Motoi, Noriko
Watanabe, Shunâichi
Article History
First Online: 10 September 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: The Institutional Ethical Committee approved the study and waived the need for individual patients to provide consent because of the retrospective nature of the study, because consent could not be obtained from all of the patients, and because individual patients were not identified in the study.