The way tissue expanders are used in breast reconstuction has changed a little as have the techniques in mastectomy for breast cancer today. In our practice in the Chicago area, most breast surgeons will save the skin of the breast when mastectomy is performed. The reconstructive plastic surgeon then has a goal of filling this form with either an implant, or at times the patient's own tissue as with an abdominal flap. The reconstruction is easier and the shape more predictable when the basic form is in place, ready to fill.
When a tissue expander is used in reconstruction, the expansion is taking place under the chest muscle (pectoralis) to give better upper coverage of the permanent implant. In some cases where the breast is small, the permanent implant can be placed right after mastectomy, though it is best to plan on an expander with most cases as the breast skin may be bruised or thin and not up to the challenge of covering the permanent implant immediately.
The tissue expander is in place through chemotherapy for most of our patients. There is no cause to rush expansion, just filling enough slowly to expand the pocket under the muscle and smooth out the skin over the surface. We do not overexpand, we will fully expand the skin out to a comfortable zone and this will give us an idea of just how full of an implant will be apppropriate. This can take the three months of chemo, though we can expand faster if treatments allow.
The expander will not look like a breast, or feel like one. Remember it is holding a space for us. We can leave it as long as we like, and the permanent implant can be placed at any convenient time in a patient's schedule.
Your own doctors techniques may differ, remember reconstructive surgery is as much art as a surgical procedure. Also keep in mind that breast reconstruction, or the treatment and rehabilation after cancer is a journey that takes time.
Best of luck,