Breast implants used in reconstruction cannot generally be placed directly in the space created by the removal of breast tissue. This is because an implant placed directly below the skin will generally not produce cosmetically desirable results and will be at high risk for eroding through the surgical incision, or through the skin itself.
Preparation of the mastectomy site for reconstruction with an implant therefore usually requires the additional insertion of one or both of these:
Tissue expansion followed by implant placement is the most common method of implant-based breast reconstruction. This approach to breast reconstruction requires two separate surgical procedures.
In order to create space and prepare the chest for reconstruction using a breast implant, a tissue expander can be used to progressively stretch the muscles of the chest, and often the skin as well. An expander is like an adjustable balloon that is gradually inflated over a period of several months to make enough room to accommodate an implant behind the stretched-out muscle. Women who undergo expander/implant reconstructions typically visit the plastic surgeon every few weeks after surgery to have the expander filled by injection with sterile fluid; this process can be somewhat uncomfortable.
Because an expander cannot be fully inflated when it is first placed, a woman undergoing this method of reconstruction will not have a new breast right after her mastectomy surgery. Once ample expansion is achieved, another surgery will be required to remove the tissue expander and replace it with a breast implant.
Learn more about the lifespan of implants and about natural-tissue breast reconstruction as an alternative to breast implants.