Clinical anatomy of laparoscopic radical prostatectomy via extraperitoneal approach

Objective To provide more knowledge that is theoretical and reduce postoperative complications by finding the useful pelvic landmarks, on the characteristics of laparoscopic radical prostatectomy basis. Methods Seven adult male pelvic specimens were anatomised. The bladder neck, both the lateral sides of prostate and the surrounding tissues of prostatic apex were observed, measured and positioned. Results There were two muscularly longitudinal fibers at the junction of the bladder neck and the prostate, with a transverse diameter of (4.42±1.38) mm and a distance of (1.78±0.32) mm from the center of the bladder. There was a constantly "claw-shaped" prostatic arterial trunk, which was (16.34±5.76) mm away from bladder-prostate groove. Pelvic plexus were located on both sides of the rectum, the upper part contributed to rectal plexus, and the lower part formed nerve vessel bundle (NVB) in the posterolateral aspect of prostate, which was approximately 5.40 mm wide. NVB contained the cavernous nerve entering the apex of prostate at 5 o'clock and 7 o'clock, with the distance of (2.84±0.56) mm. Penis dorsal nerve issued small branches into the urethral sphincter at 5 o'clock and 7 o'clock when it was (2.78±1.04) mm away from the apex. Sphincter was also innervated by the small fibers issued by NVB, distributing from 3 to 5 o'clock and 7 to 9 o'clock. Conclusion Bladder neck can be cut down according to the muscularly longitudinal fiber. The ligation of the artery can be performed at the level of 25 mm or more above the lateral aspect of groove. To avoid making damage to the cavernous nerve by recognizing small blood vessels in NVB. When separating the prostatic apex, cutting down urethra, even performing anastomosis of the bladder neck and urethra, do not damage the nerves around 5 o'clock and 7 o'clock. To find the above landmarks, the incidence of complications may be lowed. Key words: Clinical anatomy; Laparoscopic; Radical prostatectomy; Pelvic landmarks; Prostate cancer; Anatomical features