Kim, Jin Kyu
Chang, Yun Sil
Sung, Sein
Ahn, So Yoon
Park, Won Soon
Article History
Received: 20 December 2017
Accepted: 30 April 2018
First Online: 23 May 2018
Ethics approval and consent to participate
: Data collection was approved by the Institutional Review Board of Samsung Medical Center. The informed consent requirements for this retrospective chart review were waived by the Institutional Review Board.
: The authors declare that they have no competing interests.
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