Use of angular vessels in head and neck free-tissue transfer: a comprehensive preclinical evaluation.

IMPORTANCE The angular artery, its perforating branches, and their zones of tissue perfusion have been described extensively for facial reconstruction. Various cutaneous and mucosal flaps with either anterograde or retrograde perfusion play an important role in facial and oral reconstruction. However, these flaps share the limitations of pedicled nature and donor-site intolerance. Free-tissue transfer (FTT) has transformed capabilities and outcomes in head and neck reconstruction. While less constrained by tissue volume and subtype, FTT has its own limitations, including pedicle reach for anastomosis to inflow and outflow vasculature in upper face reconstruction. The angular vessels, owing to their relatively high central location and accessibility via a camouflaged nasolabial fold incision, may have value in midface and nasal reconstruction. OBJECTIVES To detail a technique for consistently locating the angular vessels while preserving the integrity of adjacent neuromuscular structures and to evaluate the caliber and consistency of the angular artery and vein for their usability in microvascular anastomosis. DESIGN AND SETTING We conducted a PubMed literature search for the terms angular artery, melolabial flap, nasolabial flap, retroangular flap, and any associations with FTT. We also performed 26 anatomic cadaveric dissections on 13 fresh cadavers to evaluate the angular arteries and veins. MAIN OUTCOMES AND MEASURES Vessel caliber, length, and variability were analyzed and utility for use in FTT was assessed. A total of 26 angular arteries and 26 angular veins were included in the analysis. Anatomic relationships were used to develop a surgical schema for dissection and isolation of the angular vessels specifically for FTT. RESULTS The angular vessels have consistent anatomic relationships facilitating localization and have a consistent caliber amenable to use in microvascular FTT. The mean (SD) artery diameter was 2.34 (0.67) mm prior to dilation and 3.21 (0.87) mm after dilation. The diameters of the vein before and after dilation were 3.57 (0.53) mm and 6.40 (0.81) mm, respectively. There was no statistical difference between the vessels on the right and left sides. CONCLUSIONS AND RELEVANCE We describe for the first time the anatomic cadaveric dissection and analysis of the angular arteries and veins specifically to determine compatibility with regard to FTT. We found good FTT compatibility. LEVEL OF EVIDENCE NA.