Comparative Study of Small Vessel (under 0.8 mm) Anastomosed Free Flap and Larger Vessel (over 0.8 mm) Anastomosed Free Flap; Does Supermicrosurgery Provide Sufficient Blood Flow to the Free Flap?

Background This study aimed to quantify the blood flow of free flaps and compare the blood flow of small vessel (<0.8 mm) and larger vessel (>0.8 mm) anastomosed free flaps.Methods This retrospective study included patients treated successfully with a perforator free flap in the lower extremity between June 2015 and March 2017. A color duplex ultrasound system measured the flow volume through the pedicle by analyzing the mean flow peak velocity, flow volume, and flow volume per 100 g of the flap.Results A total of 69 patients were enrolled in this study. There was no statistical difference in peak velocity between the small vessel anastomosed free flap (25.2 +/- 5.6) and larger vessel anastomosed free flap (26.5 +/- 5.4). Flow volume (6.8 +/- 4.2 vs. 6.3 +/- 3.6) and flow volume/100 g (3.6 +/- 3.9 vs. 6.2 +/- 6.9) also did not show significant differences.Conclusion Small vessel (<0.8 mm) free flaps showed similar flow velocity and flow volume to larger vessel (>0.8 mm) anastomosed free flaps. Blood flow to the small vessel anastomosed free flap was sufficient despite its small vessel size.