Những cổng này phải được đặt vào không gian properitoneal trong một thời trang để họ không đi qua màng phúc mạc, và được đặt theo hướng dẫn nội soi trực tiếp. Nếu màng phúc mạc được chia, sự sụp đổ của không gian properitoneal sẽ kết quả. Điều này cũng sẽ đòi hỏi phải chuyển đổi một thủ tục | 52 Bird and Winfield superiorly against the peritoneal membrane and as such usually does not need to be transected. Ports are placed in the same diamond configuration described for transperitoneal L-PLND. These ports must be placed into the properitoneal space in a fashion so that they do not traverse the peritoneal membrane and are placed under direct laparoscopic guidance. If the peritoneal membrane is divided collapse of the properitoneal space will result. This will also necessitate conversion to a transperitoneal procedure with subsequent intraperitoneal port placement. The key to dissection in this procedure involves identifying the pulsations of the external iliac vessels. At this point dissection is begun by elevating the fibrofatty and adventitial tissue off the external iliac vein and from this point the remainder of the procedure continues in a fashion similar to transperitoneal dissection. Extended Lymph Node Dissection Though obturator lymph node dissection is satisfactory for evaluation of prostate cancer an extended lymph node dissection is usually required in cases of bladder urethral and penile cancer. An extended pelvic lymph node dissection may sometimes be carried out in patients with prostate cancer and negative obturator nodes that are highly suspected of having metastatic local disease such as in cases of clinical T3 disease and or markedly elevated PSA 60 11 . For extended pelvic lymphadenectomy the fan or inverted U array as previous described is preferred because it allows for more assistance with retraction. Lymph node dissection for these disease entities usually involves carrying the dissection out to the genitofemoral nerve laterally to the bladder wall and ureter medially to the pubic bone caudally and up to the bifurcation of the aorta cranially. This procedure has many similarities to standard pelvic lymph node dissection with a few modifications that account for inclusion of a larger lymph node package with the aforementioned .
