ABSTRACT
Tissue expansion is a relatively new technique in which skin and the underlying tissue are stretched progressively over a period of weeks following the insertion of a silicone expander bag deep to the skin and subcutaneous tissue, which can be progressively enlarged by injections of sterile saline solution. As has long been known, the skin overlying benign tumours and cysts which undergo enlargement tends to expand but remains quite viable, and there may be a surplus of skin at the time of removal of such lesions. This concept was the basis of the development of tissue expansion, and it has been found that extensive expansion of skin may be obtained over a period of weeks using implanted bags, leading finally to a surplus of skin for use in either random or axial flaps (such as the forehead flap for reconstruction of the nose) without leaving a skin defect at the donor site. This is an extremely valuable technique and is now increasingly used.
