Recent advances in minimally invasive perforator flaps, such as the superficial circumflex iliac artery (SCIP) flap, have increased the demand for anastomosing vessels with diameters less than 0.8 mm. However, discrepancies in size can occur, underscoring the significance of end-to-side anastomosis. Nevertheless, the conventional interrupted end-to-side suturing technique with vessel turnover presents challenges in situations with a limited operative field, short vascular pedicle, and tiny vessels. Therefore, we developed an intravascular flipping technique for end-to-side microvascular anastomosis with an “inside” rotation method or a “rotation-outside” method. The study involved 20 rats, with 15 arteries in 10 rats undergoing the flipping technique using inside or outside rotation. Both the inside and rotation-outside techniques exhibited a 100% immediate patency rate in rats; however, after 1 week, this decreased to 80% and 86%, respectively. The SCIP flap and replantation procedures were successfully performed. The flipping technique offers several advantages, including ease of vessel manipulation using nylon threads and vascular clips, improved vessel visualization, and spontaneous widening of the vessel lumen.
