Article History
Received: 4 April 2018
Accepted: 24 May 2018
First Online: 7 June 2018
Ethics approval and consent to participate
: This study was reviewed and approved by the Institutional Review Board of Kyung Hee University Hospital at Gangdong (KHNMC-OH-IRB 2016–10-006). Informed consent was waived for all patients because the analysis used anonymous clinical data obtained after each patient agreed to treatment.
: The authors declare that they have no competing interests.
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