Funding for this research was provided by:
Special Project on the Health Care of the Chinese Military Foundation (14BJZ09)
Received: 28 December 2019
Accepted: 13 May 2020
First Online: 27 May 2020
Ethics approval and consent to participate
: This research project was approved by the ethics committee of our hospital. Because the study was a retrospective survey of medical imaging data and the anonymity of the patients’ data was maintained, informed consent was not required from patients.
: Not applicable
: The authors have no conflicts of interest to declare.