1 Department of Ultrasound Medicine, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, China.
2 Department of Ultrasound Medicine, The Second Hospital of Haerbin, Haerbin, China.
3 Department of Pathology, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, China.
4 Department of Oral and Maxillofacial Surgery, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, China. Electronic address: yuliangwang@bzmc.edu.cn.