Text and Data Mining valid from 2019-02-14
Received: 17 December 2018
Accepted: 4 February 2019
First Online: 14 February 2019
Compliance with ethical standards
: Ryota Kiuchi, Takanori Sakaguchi, Ryo Kitajima, Satoru Furuhashi, Makoto Takeda, Takanori Hiraide, Yoshifumi Morita, Takasuke Ushio, Rei Ishikawa, Satoshi Baba and Hiroya Takeuchi declare that we they have no conflict of interest.
: All procedures followed have been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.
: Informed consent was obtained from all patients for being included in the study.