Received: 10 December 2018
Accepted: 14 February 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: This study was approved by the institutional review boards of ChungBuk National University Hospital (CNUH 2018-08-014-001) and Samsung Medical Center (SMC 2018-07-154), and patients’ records were reviewed and published according to the Declaration of Helsinki. Informed consent was waived because of the retrospective nature of the study.
: Not applicable. This study did not contain any individual or personal data in any form (including individual details, images, or videos).
: The authors declare that they have no competing interests.
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