Received: 16 May 2019
Accepted: 21 November 2019
First Online: 16 December 2019
Ethics approval and consent to participate
: Ethics approval was obtained from the clinical research ethics committee at Tokushima University Hospital (approval number 2593). Informed consent to participate in the study was also obtained from patients or from an authorized surrogate.
: Not applicable.
: The authors declare that they have no competing interests.