Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology (17K10534)
Received: 15 April 2020
Accepted: 21 October 2020
First Online: 6 November 2020
Ethics approval and consent to participate
: This study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Clinical Ethics Committee of Gunma University. Written consent was obtained from all patients for the use of their records and imaging in future studies.
: Not applicable.
: The authors declare that they have no competing interests.