Comparison of Biomechanical and Histopathological Properties of Robot-Assisted Anastomoses Using the Symani Surgical System® versus Conventional Anastomoses in a Preclinical Microsurgical Model

The Symani surgical system (Symani) is the first robotic system specifically designed for microsurgical purposes and attracted substantial interest in recent times. Despite some initial investigations, no independent analysis of the histopathological/biomechanical properties and anastomoses quality of Symani-sutured anastomoses have been conducted so far. This study aims to compare in-depth robotic-assisted microsurgical anastomoses using the Symani versus conventional anastomoses regarding anastomosis quality, biomechanical, and histopathological properties.We compared 12 microsurgical end-to-end anastomoses sewn by the Symani versus 12 by the conventional technique in a preclinical artery chicken-thigh-model regarding time until completion of the anastomosis, anastomosis quality (modified MARS10-rating and anastamosis lapse index (ALI)) and diameter. Additionally, histopathological analysis of the thread hole diameter, and knot firmness as well as biomechanical tests for intraluminal resistance and tensile strength of the anastomoses were conducted.Anastomosis quality was comparable between both techniques. The Symani-assisted anastomosis took a significantly longer time to perform than conventional anastomosis. Histopathological analysis revealed similar vessel wall damage while showing greater variability in knot spacing and bite width in the robotic anastomoses. No significant differences were observed in the tensile strength test or intraluminal resistance. However, the knot firmness of Symani-assisted anastomosis was significantly less than conventionally performed knots.This study demonstrates that the Symani performs on par with conventional anastomosis techniques regarding anastomosis quality, vessel wall damage, intraluminal resistance, and tensile strength. Long-term continuous training and/or further innovations of the Symani system may lower the time required to perform the anastomosis and improve knot firmness.