Tissue expanders are medical devices used in reconstructive surgery to generate new skin and soft tissue on the body. They are an effective method for creating additional tissue when a patient’s own tissue is insufficient for reconstruction. These devices restore appearance and function following various medical conditions or injuries.
Mechanism of Action
Tissue expansion operates on the body’s natural ability to grow new tissue in response to sustained stretching. A silicone balloon-like expander is surgically placed beneath the skin or muscle where extra tissue is needed. Over weeks or months, the expander is gradually filled with sterile saline solution through a small, self-sealing valve, which may be integrated or located remotely under the skin.
The gradual inflation of the expander applies continuous tension to the surrounding skin. This mechanical stress stimulates cells in the epidermis to proliferate, increasing its thickness. The stretching also encourages the formation of new skin cells and blood vessels, creating new tissue that matches the color and texture of adjacent skin. This process leverages both mechanical and biological creep to achieve tissue gain.
Primary Medical Uses
Tissue expanders are used in reconstructive procedures where additional skin is required. A primary application is breast reconstruction following a mastectomy, where expanders create space and new tissue to accommodate a permanent breast implant or reconstruct the breast mound. This approach allows for a more natural-looking outcome by developing skin that closely matches the original breast.
These devices also repair skin damaged by severe burns or trauma, providing healthy, expanded skin to cover large defects and improve functionality. Tissue expanders help correct congenital deformities, such as ear or scalp defects, by generating enough skin to reshape or cover the affected area. They are also used for large scars or areas where tissue has been removed, by stretching surrounding healthy skin to replace the scarred or missing tissue.
Understanding the Procedure
Tissue expansion begins with an initial consultation where the surgeon assesses needs and develops a treatment plan. The first surgical step involves implanting the tissue expander, often as an outpatient procedure. The expander is placed under the skin or muscle near the area to be reconstructed.
Following initial surgery and a healing period of one to two weeks, the expansion phase begins. Patients visit the doctor’s office every one to two weeks for saline injections into the expander’s port. Each injection gradually increases the expander’s volume, stretching the overlying skin.
Patients may experience tightness, pressure, or discomfort during and after these sessions, which subsides within a few hours. The entire process can span several weeks to many months, depending on the amount of tissue needed. Once sufficient tissue is generated, a second surgical procedure removes the expander and uses the newly grown tissue for final reconstruction.