Nasal Unit Transplantation: A Cadaveric Anatomical Feasibility Study.

The science and technical acumen in the field of vascularized composite allotransplantation has progressed rapidly over the past 15 years, and transplantation of specialized units of the face, such as the nose, appears possible. No study to date has evaluated the technical feasibility of isolated nasal unit transplantation (NUT). In this study, we explore the anatomy and technical specifics of NUT.  In this study, four fresh cadaver heads were studied. Bilateral vascular pedicle dissections were performed in each cadaver. The facial artery was cannulated and injected with food dye under physiologic pressure in two cadavers, and with lead oxide mixture in two cadavers to evaluate perfusion territories supplied by each vascular pedicle.  The facial artery and vein were found to be adequate pedicles for NUT. Divergent courses of the vein and artery were consistently identified, which made for a bulky pedicle with necessary inclusion of large amounts of subcutaneous tissue. In all cases, the artery remained superficial, while the vein coursed in a deeper plane, and demonstrated consistent anastomoses with the superior transverse orbital arcade. While zinc oxide injection of the facial artery demonstrated filling of the nasal vasculature across the midline, dye perfusion studies suggested that unilateral arterial inflow may be insufficient to perfuse contralateral NUT components. Discrepancies in these two studies underscore the limitations of nondynamic assessment of nutritive perfusion.  NUT based on the facial artery and facial vein is technically feasible. Angiosome evaluation suggests that bilateral pedicle anastomoses may be required to ensure optimal perfusion.