A Novel Intraluminal Microtube Anastomosis System (IMAS) for Rapid Rat Microvascular Reconstruction: Development and Experimental Evaluation

Background/Objectives: Conventional interrupted microvascular anastomosis is technically demanding and time-consuming. We developed an intraluminal microtube anastomosis system (IMAS) in which circumferential anchoring ridges on the outer surface mechanically retain each arterial end while two external circumferential ligatures secure the reconstruction. This study compared IMAS with conventional interrupted microsurgical anastomosis in a rat infrarenal abdominal aortic model.

Methods

Forty male Sprague Dawley rats (250–300 g) were allocated to IMAS (n = 20) or conventional interrupted microsurgical anastomosis (n = 20). Random-sequence generation and allocation concealment were handled by an animal-experiment assistant. All formal procedures were performed by the same surgeon, who was proficient in conventional microsuturing and had completed 10 pilot IMAS procedures before the study. Anastomosis time was measured from complete aortic transection to restoration of flow after clamp removal. Patency was assessed at 1 week and 1 month by color Doppler ultrasonography, with terminal gross examination at 1 month. The study was exploratory and was not powered as a patency non-inferiority or equivalence study.