Zhongbao Zhou1, Zhenli Gao1, Jitao Wu1, Yuanshan Cui2,3. 1. Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, NO. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China. 2. Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, NO. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China. doctorzzb@163.com. 3. Department of Urology, Beijing TianTan Hospital, Capital Medical University, No.119 South 4th Ring West Road, Fengtai District, Beijing, 100070, China. doctorzzb@163.com.