has been dilated and the anvil of the circular stapler insert- ed. The anvil is then grasped with a clamp introduced through the right flank trocar site and the bowel replaced in the abdomen. In this way it is possible to avoid loss of time in grasping the stapler head, and, most of all, possible torsion of the bowel. To perform an end-to-end, transanal anastomosis, it is better to use the latest generation of cir- cular staplers (Plus CEEA, U.S Surgical Corp.), furnished with a dumping head, which avoids any tension on the anastomosis at the moment of removing the stapler. After suture of the minilaparotomy, the peritoneal cavity is rein- sufflated, and, having introduced the circular stapler transanally, the rectal stump is perforated, and the stapler head coupled, performing a Knight-Griffen, end-to-end anastomosis. Besides checking the colic and rectal dough- nuts left in the circular stapler, we always test the anasto- mosis. After the colon is re-approximated, the pelvis is filled with physiological saline. The rectal lumen is insuf- flated with air through a large-gauge Foley catheter until the anastomotic segment is distended, to assure that the anastomosis is airtight. The operation is completed with placing of a retroanastomotic drain that exits the right iliac fossa trocar port. ANTERIOR RESECTION OF RECTUM The patient, surgical unit and port accesses are positioned essentially in the same way as in left hemicolectomy (Figures 3-4). In female patients, it is important that the uterus be suspended up and away by a transcutaneous stitch. There is no particular difficulty in detaching the rec- tum from the presacral plane. Anterior and lateral to the rectum, it is useful to identify and define the ureters and, in male patients, the vas deferens and seminal vesicles. To avoid sinking into perirectal fat, one should remain on the plane of the urogenital organs and the aponeurosis of Denonvillier. During this phase of the operation it is ben- eficial to utilize the bipolar graspers for hemostasis and transection of the middle hemorrhoidal vessels and alar lig- aments of the rectum. Some deem it necessary to check the distal margin of resection, performing an intraoperative rectoscopy without traversing the tumor and spilling neo- plastic cells. In some cases it is useful to insert an addi- tional trocar in the suprapubic region to perform a perpen- dicular transection of the rectum, avoiding the necessity of exteriorizing, transanally, the rectal stump. A Knight- Griffen end-to-end anastomosis is performed with a circu- lar stapler. The operation is completed testing the anasto- mosis and positioning a peri-anastomotic drain to exit the inferior right trocar port. In very low resections it is better to perform the division and purse-string suture of the distal stump by hand, in some cases after the stump has been delivered transanally. Hand-suturing is frequently neces- sary because linear staplers are difficult to maneuver in the tight confines of the pelvis and there may occur a postop- erative anastomotic leak with improper placement of the staple unit. LAPAROSCOPIC RESECTION ABDOMINOPEREVEAL The patient is placed in a gynecologic and Trendelenburg position, with shoulders, chest and legs firmly secured to the operating table. The operating surgeon and camera person are positioned at the patient's right side, the assis- tant at the left, and the monitor next to the patient's left foot (Figure 5). Having induced pneumoperitoneum with a Veress needle inserted in the right paraumbilical region, the first trocar is positioned in the same site. Laparoscopic exploration of the abdominal cavity is performed. Placing the remaining trocars is accomplished in a way that allows visualization of the pelvis, sigmoid colon and inferior mesenteric artery. A second trocar is placed in the left pararectal region, at the site at which colostomy is to be performed. During this phase of the operation, great care must be taken to avoid damage to the epigastric vessels that flow in this region. This concern is easily overcome with transillumination of the abdominal wall from inside the body cavity with the laparoscope. Two additional trocars are placed in the right flank and one in the right iliac fossa (Figure 6). These two trocars should be spaced to prevent clashing of the instruments during their use. After the loops of the small bowel are moved upwards to the right, the peritoneum is incised anterior to the right iliac artery and medially to the right ureter. Moving upwards, the origin of the inferior mesenteric artery is identified. Dissection in this region is facilitated by lateral retraction of the sigmoid upwards toward the anterior left abdominal wall by the first assistant utilizing bowel forceps. Dissection is continued to the left, until ureter and left gen- ital vessels are visible. These structures are isolated and detached from the mesosigmoid. The inferior mesenteric artery is ligated at the origin of the left colic artery, with metal clips, a vascular stapler such as Endo-GIA 30, or with extracorporeal knots. If the inferior mesenteric vein flows close to the artery, it can be sectioned together with it. If the mesenteric vein is not in close approximation, it is iso- lated and ligated separately. After having detached the ureter and left genital vessels, the mesosigmoid is divided with bipolar forceps, metal clips, or staples, care being taken to secure the mesenteric and marginal vessels. After the sigmoid is detached from its mesentery, it is divided using a 30 mm Endo-GIA with vascular cartridge. Dissection is continued towards the pelvis, dividing the peritoneum on both sides of the rectum. During this phase, the left ureter must be identified and protected. The rec- tum and its mesentery is then subject to a posterior, lateral, and finally anterior mobilization. Using a 10 mm palpation probe shaped like a paddle (Karl Storz GmbH), it is possi- ble, to completely detach the mesorectum from the sacral plane. After the alar ligaments of the rectum are coagulat- ed and divided, the rectum is retracted upwards, and dis- section continued down to the floor of the pelvis, perform- JSLS (1997)1:217-224 221