Geometry of the vascular pedicle in free tissue transfers to the head and neck.

Traditionally, the most important parameters for success in free tissue transfer have been expertise in performing small vessel anastomoses, meticulous donor site dissection, and careful recipient vessel preparation. It has been our experience, in free flap transfers for head and neck reconstruction, that a very crucial, often unrecognized, parameter is the geometry of the vascular pedicle. This term encompasses the three-dimensional positioning of the nutrient vascular pedicle as well as vessel tension and redundancy. The ideal axis for the lie of the vascular pedicle in the neck is in the longitudinal direction. This configuration helps to eliminate the kinking of the pedicle that is observed with side-to-side movements of the head. The primary objectives in recipient vessel selection are to use a healthy artery and vein and to perform the anastomoses in a location that provides easy access for the surgeon and assistant. Recipient vessel selection is also a major determining factor in the achievement of the desired pedicle geometry. We believe that the transverse cervical artery and the external jugular vein are the best recipient vessels for free tissue transfer. The reasons for this selection, as well as technical details to improve pedicle geometry, are discussed in depth. Representative cases that demonstrate pitfalls in vascular pedicle geometry are presented.