**2.2. Intracorporeal Billroth I anastomosis**

#### *2.2.1. Delta-shaped anastomosis*

The delta-shaped anastomosis originally created by Professor Kanaya is a functional end-toend gastroduodenostomy technique using endoscopic linear staplers [7].

For the duodenal bulbus resection, the direction of the stapling is more vertical than the mesenteric-antimesenteric direction. End-to-end anastomosis is done vertically to maintain an enough blood supply to the anastomosis and to preserve a space for the jaw of 45-mm linear stapler to be inserted into the entry hole. Before stapler firing, the staple line on the remnant stomach is rotated to the left side, and the staple line on the duodenal stump is rotated to the right side to form a side-to-side gastroduodenostomy between the posterior wall of the remnant stomach and the posterior wall of the duodenum. After firing the stapler, a relatively large entry hole is made, and the operator checks for anastomotic bleeding through this hole. After transient approximation of the entry hole with clips, the hole is closed by two consecutive firings of a 45-mm liner stapler.

#### *2.2.2. Intracorporeal triangular anastomotic technique (INTACT)*

The other intracorporeal anastomosis method, novel intracorporeal triangular anastomotic technique, was reported by Omori et al. [8].

After all dissection of lymph nodes is finished, the stomach and duodenal bulb are stapletransected parallelly, and the resected stomach with dissected LNs is retrieved through the umbilical incision. Small entry holes are made on the greater curvature side, for each of the remnant stomach and the duodenal bulb, leaving a space almost 1 cm away from each stapling line. The cartridge side of the linear stapler (45-mm articulating medium/thick cartridge) is inserted to the transection line of the stomach. Then, the linear stapler fork side is carefully inserted into the bulb via the hole parallelly. This process makes The cartridge side is inserted parallel to the transection line of the stomach. The posterior walls, so-call V-shaped anastomosis, of both the gastric remnant and the bulbs, the dorsal side of the posterior suture line of the Billroth I. After arresting hemorrhage of the suture line, the entry hole is sutured by 2–3 points temporarily, avoiding slipping the liner staple. Finally, the entry hole is closed by a 45-mm linear stapler suture and created completing the anterior half of the anastomosis. The almost 60° anastomotic angle between the second anastomotic line and the first suture line is best designed for passing the food. This second anastomotic line length should be approximately 30 mm without the ventral staple lines. Thirdly, the linear staple with a 60-mm articulating medium/thick cartridge is placed in the direction toward the posterior wall and also placed almost perpendicular to the transection line of the stomach for resecting the blood less area. Those three staplers created the triangular anastomosis and simultaneously removed three staple lines of the duodenal transection line, the ventral line of the first anastomosis, the end of gastric transection line, and the ischemic tissues in between these staple lines. This technique yielded an end-to-end anastomosis of a triangular orifice [9].
