This 3D animation from The Human Atlas explains Breast Reconstruction.

Following a mastectomy, or the surgical removal of breast tissue, many women choose to have breast reconstructive surgery for both emotional and physical reasons.

Sometimes, the skin where the breast has been removed needs to be stretched before the reconstructive surgery can occur. This is accomplished by inserting a type of implant, called an expander, beneath the skin and chest muscle. An expander is similar to a balloon, and it is slowly filled with a saline solution at periodic intervals.

When the skin has been stretched adequately, a second surgery will be performed to remove the expander and to replace it with a permanent implant. However, under certain conditions, the expander can be left in place permanently.

Another common breast reconstruction method involves using healthy skin and muscle from other areas of the body. One method is to use a section of skin that is attached to the latissimus muscle in the back. Another method uses part of the abdominal rectus muscle, which can be slid up into the breast area as part of breast reconstruction. Many women also choose to have nipple reconstruction and breast implants with whichever form of breast reconstruction they choose.

Reconstructive breast surgery can be performed at the time of mastectomy although it's common for women to make the decision for reconstruction at some point following mastectomy.

There are several potential complications associated with this procedure that should be discussed with a doctor prior to surgery.