Tissue Expansion

Through an incision in the skin, with delayed reconstruction or at the time of the mastectomy, an empty medical balloon is inserted beneath the chest muscles. A separate valve is attached to this balloon, which is placed beneath the chest skin and left undisturbed for a few weeks. The balloon is gradually inflated on a weekly or bi-weekly basis by passing a thin needle into the valve through which a sterile solution is injected. A mild pressure sensation may be felt during this process but the discomfort is brief and most women find it bearable.

The gradual inflation of the balloon continues until it is over-inflated. This ensures that sufficient skin and muscle are available to match the larger, opposite breast, or allows the placement of a permanent implant in situations that might require the addition of other tissues, as in tissue transfer. Usually, this over-inflated state lasts from four to six months to allow for stretching of the tissues making up the mound before the second stage is attempted. Difficulty in wearing some clothing and certain physical limitations may be experienced during the expansion.

Stage two involves the exchange of the expanded balloon for a permanent prosthesis similar to that described above for a simple submuscular reconstruction. This may be done under either local or general anesthetic. When necessary, the shape of the breast can be altered during this stage or the crease under the breast can be moved or reestablished. As with submuscular reconstruction, the hospital stay is limited. Activity levels are similar, and post-operative discomfort is usually not severe. The final shape of the breast mound will take many months to finish healing.

In some cases, a permanent tissue expander is placed under the chest muscles. This type of implant requires that only the valve is removed (under local or general anesthetic) when the breast has achieved its desired shape and size. The drawbacks in using this prosthesis include the inability of the doctor to further refine the breast after the expansion has taken place either by altering the position of the prosthesis, repositioning the lower breast crease, or by substituting another implant.

For those women who lack sufficient quantities of tissue despite tissue expansion, or those with poor quality tissues left after the mastectomy, healthy and plentiful skin, fat and muscle from other areas of the body can be transferred to the chest (tissue transfer).