Extraperitoneal colostomy in robotic surgery for rectal cancer using a tip-up fenestrated grasper.

INTRODUCTION Although extraperitoneal colostomy could reduce the risk for parastomal hernia formation, it is often technically demanding to dissect the extraperitoneal route laparoscopically. Here, we demonstrate our original surgical technique for extraperitoneal tunneling using a robotic instrument. MATERIALS AND SURGICAL TECHNIQUE After total mesorectal excision (TME) and before specimen retrieval, the edge of the outer leaf of the parietal peritoneum was elevated by the grasper in the left hand and the tip-up fenestrated grasper (Tip-Up) in the right hand. The extraperitoneal tissue was opened using the scissor forceps (right hand). Then, extraperitoneal tunneling (inner tunnel) was performed using a Tip-Up with a width of approximately 4 cm that could reach adjacent to the lateral border of the abdominal rectus muscle. A round incision was made at a preoperatively marked site on the skin. The anterior rectal sheath was cut in a cruciate fashion. The abdominal rectus muscle was split, and then the posterior rectus sheath was cut longitudinally not just below the stoma marking site but also at a slant on the lateral side. The peritoneum was dissected with care to avoid opening the peritoneum. The outer side of the tunnel was broken through to the inner tunnel using an easy blunt dissection with two fingers. Kelly forceps were introduced through the extraperitoneal tunnel along with the fingers, and the stump of the sigmoid colon was grasped and exteriorized through this tunnel. DISCUSSION Robotic retroperitoneal tunneling using a Tip-Up is easy and useful for preventing parastomal hernia.