SIEA Flap (Superficial Inferior Epigastric Artery Flap)
A SIEA flap is a microsurgical breast reconstruction where skin, fat and the associated blood vessels that keep it alive are transplanted to the chest wall from the abdomen during the Stage 1 Procedure. No muscle is sacrificed in the execution of this form of breast reconstruction. Blood vessels of the flap are connected to either blood vessels in the chest wall or under the arm in the axilla using an operating room microscope. Unilateral and Bilateral SIEA flap breast reconstruction can be performed in a 4-6 hour general anesthetic in the setting of a 4-day hospital stay with a focus on flap monitoring. It is a minimally painful operation, less than a TRAM, but typically more that a GAP flap. Blood thinners are administered to prevent deep venous thromboses or pulmonary emboli. Costochondral cartilage or rib resection is uncommon unless you are a very petite woman.
Stage 2 of this technique involves the aesthetic shaping of the breast reconstruction flap and the completion of any counterbalancing procedures of the remaining breast (breast reduction, breast lift or breast augmentation). Excess skin from the flap previously placed for perioperative monitoring will be removed. Revisions to the donor site include liposuction and scar revisions. Nipple reconstruction is completed at this stage. Stage 2 procedures can be completed in a 2-hour MAC anesthesia in an outpatient setting. On occasion in the irradiated patient, nipple reconstruction is deferred to a later date allowing for the revised reconstruction to settle, therefore optimizing nipple placement. Areolar reconstruction will be completed as a Stage 3 procedure in 2 months in the office.
SIEA flap breast reconstruction has not been associated with buldging of the abdominal wall, abdominal wall weakness or hernia as the fascia overlying the rectus abdominus muscle is not incised. It has not been associated with post-operative back pain. Common complications are seromas or collections of fluid under the skin that may require needle aspiration.
SIEA total flap failure can be seen in less than 2% of cases.
Flap failure can result from 3 etiologies:
1. Inadequate flap blood vessel anatomy i.e. in the setting of prior abdominal wall surgery or SIEA diameter < 1.5 mm;
2. Inadequate recipient blood vessels in the chest or axilla (likely secondary to prior surgery, irradiation, or prolonged exposure to silicone gel);
3. Injury to the essential blood vessels of the flap at the time of surgery;
SIEA total flap failure is diagnosed prior to your release from the hospital. Most patients with a failed SIEA flap undergo a secondary microsurgical flap procedure during the same hospitalization or at a later date, typically at 3 months, in the form of an I-GAP flap (see below).
SIEA partial flap loss is commonly referred to as fat necrosis. Fat necrosis can present as a firm area of the breast reconstruction flap where the blood supply was not adequate enough to keep the tissue soft and viable. It likely represents an anatomic variant of the individual (not unlike a "hole" in your Christmas tree...), OR possibly the poor choice of the SIEA to support the flap reconstruction. The desire to avoid fat necrosis fuels Dr. Marga's desire for a pre-operative CT or MR angiogram so your procedure can be based on the most robust blood vessel of your abdominal wall.
Dr. Marga is a microsurgery-fellowship-trained Plastic Surgeon with a focus on SIEA flap breast reconstruction at the Center for Restorative Breast Surgery. She would be pleased to discuss with your the differences in the selection of DIEP vs. SIEA flap breast reconstruction in the setting of your office or phone consultation.