Tissue expansion in the head and neck. A 6-year review.

More than 100 patients (38 in the head and neck) have been treated by the insertion of tissue expanders since the technique was introduced six years ago. Our methods have been refined as we have learned more, and these improvements are described. Morbidity is high when untrained surgeons start to use the technique. The most important decision is the planning of the expander and filling port pockets, but above all the location of the incision(s): Incisions must be kept small and away from the defect, the pocket, and the future flap. Intraoperative filling of the expander reduces the need for drains by preventing haematoma and seroma formation, and reduces the formation of expander envelope folds. The optimal location of the valve is a "quiet" area above or lateral to (or both) the expander, and at least 7 cm away. Mathematical formulas are useless in predicting available flap length, as elasticity and contractility depend on individual factors. A good estimation of flap length is twice the height of the expander above the skin surface or the distance over the dome of the expander minus the corresponding measurement of its base. Overexpansion by 30-50% makes the procedure more predictable.