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Updated September 03, 2013.

Definition: noun an implantable, expandable device used in breast reconstruction surgery. Tissue expanders have silicone outer shells and a valve, injection dome or external port to allow for injections of saline fluid. Breast cancer patients will be offered a variety of shapes and sizes of tissue expanders, if they choose breast implants as their breast reconstruction method.

Also Known As: breast expander, temporary breast implant, tissue stretcher

Examples:

After a mastectomy, a tissue expander is inserted beneath chest wall muscles where it is positioned within a pocket of tissue. When the mastectomy incision has healed, saline will gradually be injected to expand the surrounding tissues and create space for a permanent breast implant.