Transverse rectus abdominis myocutaneous (TRAM) flap surgery involves construction of a breast from the lower abdominal skin and fatty tissue attached to the abdominal muscle. TRAM flap procedures may be pedicled or free.
In a pedicled TRAM flap procedure, the blood supply remains attached to the lower abdominal tissue, which is rotated into position on the chest. The tissue is tunneled under the skin to the chest area, where it is brought through the mastectomy incision.
In a free TRAM flap procedure, the skin and all tissues are completely disconnected from its blood supply, moved to the area of the breast, and then reconnected to different blood vessels. These very small blood vessels are often sewn together under a microscope.
A muscle-sparing free TRAM may be possible for some patients. Mayo surgeons use an abdominal muscle plug about two inches by two inches in diameter plus skin and fat to create a new breast mound. Most of the abdominal muscle is undisturbed, resulting in less loss of abdominal muscle function than results from a free TRAM procedure. The blood supply must be reconnected.
In the latissimus flap procedure the surgeon moves the flap from the upper back to the chest site to construct the new breast. Because the latissimus flap usually provides less tissue than the TRAM flap, an implant is often added to provide sufficient volume.
A benefit of both pedicled and free TRAM flap procedures is the effect of a tummy tuck (surgery that tightens the skin over the stomach) due to tissue moved from the abdomen to the site of the new breast.
Both pedicled and free TRAM flap procedures, however, may also result in a loss of abdominal muscle tone due to manipulation of the rectus muscle. Various procedures have been developed to prevent muscle tone loss, but the surgeon may not know if the patient is a candidate to receive them until the operation is under way.