Optimal Intracorporeal Anastomosis for Colectomy: A Comparative Experimental Evaluation Using 3D Anastomosis Models

INTRODUCTION: Application of intracorporeal anastomosis is gradually becoming widespread; however, there are no detailed reports on its configuration. We aimed to create three-dimensional intracorporeal anastomosis models and compare their configurations in detail. METHODS: Three types of intracorporeal anastomosis models were used: overlap anastomosis, delta-shaped anastomosis, and functional end-to-end anastomosis. In experiment 1, three-dimensional images of each anastomosis model were created. Additionally, the length of each staple line comprising the anastomotic site was measured. In experiment 2, the lengths of intestinal mobilization required for different anastomoses were compared. RESULTS: The circumference of the anastomosis in overlap anastomosis (141.5 ± 3.3 mm) was significantly greater than that in delta-shaped anastomosis (87.9 ± 0.9 mm; p < 0.001) and functional end-to-end anastomosis (89.6 ± 10 mm; p < 0.0001). The length of the intestinal tract after anastomosis in delta-shaped anastomosis (33 ± 6.9 mm) was significantly shorter than that in functional end-to-end anastomosis (76 ± 2 mm; p < 0.0001) and overlap anastomosis (60 ± 5 mm; p < 0.002). CONCLUSIONS: We successfully constructed three-dimensional images of intracorporeal anastomosis models. These results suggest that overlap anastomosis led to the formation of the largest anastomotic site, while minimal bowel mobilization was required in the delta-shaped anastomosis.