The procedure to reach the pelvic floor after dissection of the recto-sacral ligament is similar to that of LapLAR; however, after reaching the pelvic floor, the operative procedure differs.

At this point, the caudal edge of the S4 pelvic splanchnic nerve that rises from the sacrum can be confirmed. Here, the rectum is dissected bilaterally to the caudal-ventral side, the supralevator space resembles a comma-like space, but the procedure must not extend to the nearby the anorectal region (Fig. 5.2).

In the retrorectal space, when dissection is performed toward the caudal side, the anococcygeal raphe is visually recognized as directed from the coccyx to the rectum. If the dissection is performed slightly distant from the midline, the anococcygeal raphe is clearly exposed (Fig. 5.2). A minimal dissection of the bilateral mesorectum is performed far from the hiatal ligament. The anococcygeal raphe is divided near the coccyx and the levator ani muscle is divided into a U-shape using an ultrasonically activated device (USAD) (Fig. 5.2). Distancing from the rectum as far as possible, the iliococcygeus muscle and the pubococcygeus muscle (the levator ani muscle) are divided to the ventral side into a U-shape by the USAD, to expose the granular fatty tissue of the ischiorectal fossa (Fig. 5.3).

When bleeding occurs before reaching the pelvic floor, the field of view is no longer visible for the operation. Thus, sufficient haemostatic control is mandatory.

It is important to dissect sufficiently as far as possible between the prostate and Denonvilliers’ fascia. Denonvilliers’ fascia is separated from the prostate at the terminal end by an USAD. In addition, at the lateral portions of the rectum, the rectal branches from the pelvic plexus are further divided using the USAD.

The operator’s right hand: an electrosurgical knife with spatula-type blade and Endo-GIA^TM

After determining where the sigmoid colon is to be divided, the sigmoid mesocolon is divided from the cranial stump obtained from the lymph node dissection. In cooperation with the assistant, a view of the mesocolon is obtained and the mesocolon is divided with the USAD and the sigmoid colon is then divided using a flexible Endo GIA^TM (Fig. 5.4).

The anus is sutured and closed with purse-string sutures. The patient is in the modified Lloyd-Davies position with further bending, and the perinaeum is fully visible. Following a second thorough disinfection of the perineum, an incision is made several centimetres distant from the anal verge (Fig. 5.5). The anatomical landmarks are the coccyx on the dorsal side, bilateral ischial tuberosity on the lateral side, and the perineal body on the ventral side in men. Although the skin guideline acts as the midpoint between the above and the closed anus, a broad skin excision does not lead to a better dissection. A Loan-Star wound retractor^TM is used to raise the edge of the skin incision (Fig. 5.5). The subcutaneous fat is excised. If the lesion is a far advanced cancer, the incision is made using the medial edge of the gluteus maximus muscle as an index.

Without exposing the gluteus maximus muscle, which is located dorsally and bilaterally, the dissection proceeds towards the coccyx tip as the anatomical landmark, there the granular fatty tissue of the ischiorectal fossa becomes visible. It is possible to reach the peritoneal cavity easily on the ventral side of the coccyx. Since the levator ani muscles have been divided into a U-shape, the passage between the abdominal cavity and the perineum may be incised into a U-shape at this point (Fig. 5.3)