Choi, Young Hyo
Yu, Ji Woong
Jeong, Byong Chang
Seo, Seong Il
Jeon, Seong Soo
Lee, Hyun Moo
Jeon, Hwang Gyun
Article History
Received: 30 July 2018
Accepted: 4 January 2019
First Online: 12 January 2019
Ethics approval and consent to participate
: Our Institutional Review Board (IRB) approved this retrospective study and waived the requirement for informed consent (IRB no. 2018–04-082).
: Not applicable.
: The authors declare that they have no competing interests.
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