Ductus deferens輪精管 1. Testicular part睾丸部 extends form the tail of epididymis to the superior extremity of testis 2. Spermatic part精索部 extends form superior extremity of testis to the superficial inguinal ring the place where the vasectomy is performed 3. inguinal part腹股沟部 extends form superficial to deep inguinal rings 4. Pelvic part盆部 crosses the obturator neurovascular bundle and the ureter to reach the base of bladder, where it expands to form the ampulla ductus deferentis输精管壶腹Ductus deferens 输精管 1. Testicular part 睾丸部 －extends form the tail of epididymis to the superior extremity of testis 2. Spermatic part 精索部 －extends form superior extremity of testis to the superficial inguinal ring, the place where the vasectomy is performed 3. Inguinal part 腹股沟部 －extends form superficial to deep inguinal rings 4. Pelvic part 盆部 －crosses the obturator neurovascular bundle and the ureter to reach the base of bladder, where it expands to form the ampulla ductus deferentis 输精管壶腹