Received: 29 December 2018
Accepted: 19 August 2019
First Online: 23 August 2019
Ethics approval and consent to participate
: The present study was approved by the Institutional Review Board of Kaohsiung Veterans General Hospital KVGH; (approval nos. VGHKS97-CT3–14, VGHKS98-CT1–08 and VGHKS15-CT5–10) and all patients provided written informed consent.
: Not applicable.
: The authors declare taht they have no competing interests.