Ahn, Su Joa
Kim, Jung Hoon
Park, Sang Joon
Kim, Seung Tack
Han, Joon Koo
Article History
First Online: 18 September 2018
Compliance with ethical standards
:
: No funding.
: All authors confirm that no disclosure of potential conflicts of interest.
: This retrospective study was approved by our institutional review board, and the requirement to obtain written, informed consent was waived.