Received: 23 September 2019
Accepted: 10 December 2019
First Online: 27 December 2019
Ethics approval and consent to participate
: This study was performed in accordance with the Declaration of Helsinki for medical protocols and was approved by the Wakayama Medical University Institutional Review Board (Nos. 1689 and 1698). General consent was given by the patients.
: The authors declare that they have no competing interests.