Qiao, Pan
Xu, Tian-Tong
Zhang, Wen
Tian, Rong
Article History
Received: 11 December 2017
Accepted: 5 April 2018
First Online: 18 April 2018
Ethics approval and consent to participate
: Because this was a retrospective study using data routinely collected, according to a waiver issued by the ethics committee of Tianjin Union Medical Center, specific ethics approval for this study was not required. Each patient was assigned a number, and data for patient age, sex, presence or absence of MC, MC type, and the respective segmental level were collected.
: The authors declare that they have no competing interests.
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