SIEA Flap Breast Reconstruction

The SIEA flap can be used for immediate or delayed breast reconstruction.  This figure to the right depicts the basic anatomic components of the SIEA flap.  The isolated flap is similar to the DIEP flap, but the arterial supply and venous drainage are different.  The DIEP requires the deep inferior epigastric vessels for circulation, necessitating intramuscular dissection and violation of the rectus sheath.  The SIEA flap relies on superfical vessels just below the skin surface.  The SIEA flap allows for less operative dissection, no muscle or fascia injury, and less operating time.  This flap is technically more demanding that the DIEP flap because of the small vessel size, and should only be performed by experienced microsurgeons and microsurgical teams.  Some patients do not have adequate superficial inferior epigastric vessels - a determination that is made intraoperatively.  The decision is made on the basis of vessel size.  These patients can typically be reconstructed with the DIEP flap.

SIEA DESIGN IN BREAST RECONSTRUCTION

The elliptical shaped flap can be contoured to reconstruct a breast by trimming excess tissue and sculpting the flap.  Some authors have reported an increased incidence of fat necrosis using flap that crosses the midline, but we have not found that to be the case when intraoperative finding suggest good contralateral blood flow.

Below, the the schematic illustrates the cross section of the flap with the superficial inferior epigastric artery and vein supplying the skin and subcutaneous fat paddle.  No muscle or rectus sheath are present in the flap.

THE SIEA IS HARVESTED AND TRANSPLANTED TO THE CHEST

In the schematic below the flap has been removed from the operative field in the right sided schematic.  The flap can be split in half to reconstruct two breasts or a smaller sized breast.  It need not be split in half if more soft tissue is required for a single sided reconstruction.  In this illustration a single flap is used.

CIRCULATION IS RE-ESTABLISHED

The flap has been brought into the mastectomy field and the blood vessels have been microsurgically repaired to branches the internal mammary artery and vein or perforators to the pectoralis muscle can also be used medially, often if the axilla has been radiated. 

The flap is tailored to make it as symmetrical as possible with the other breast.  A scar from the incision required for the mastectomy, sometimes extended medially or laterally for vessel exposure, is present.  The nipple areola reconstruction is usually scheduled for a later date, when all tissue has healed.  Secondary revision surgery may be required on the breast at a later date to approve appearance or symmetry.  The rectus sheath fascia is left intact and no dissection is performed on the rectus muscles.  The abdomen is closed in an abdominoplasty (tummy-tuck) fashion and a new umbilicus is fashioned.