Received: 30 October 2019
Accepted: 17 January 2020
First Online: 29 January 2020
Ethics approval and consent to participate
: The Yamagata University School of Medicine Institutional Review Board approved this study (reference number: H29–248) with a waiver of informed consent, based on this study’s design which contains no direct intervention on patients and collects no data regarding patient identification.
: Not applicable.
: KM declares that he has received honorarium from Terumo Corporation, which sells the PX-UV devices in Japan. The other authors declare that they have no competing interest.