Perforator Flaps in Breast Reconstruction
The Surgical Technologist | February 2004 | Vol. 36 | Num. 3
Robert J. Allen, M.D., Eileen Black, M.D., and Nicholas Jones, BS
New Orleans, LA
While most women who are diagnosed with breast cancer can successfully be treated with breast conservation, there are still many patients that require mastectomies. Following these procedures, women often choose to undergo breast reconstruction to restore the body image. After treatment, the patient is usually evaluated by a plastic surgeon and options on reconstructions are discussed based on the patient's preference and suitability. Options include expanders, implants, or reconstruction using autogenous tissue.
Currently, implants and tissue expanders are the mainstay in the United States. However, the use of autogenous tissue is increasing due to the controversy surrounding implants and the relatively high rate of complications, such as capsular contracture and infection.
Although the ideal material for reconstruction of the breast is skin and fat alone, most current methods of autogenous reconstruction use myocutaneous flaps. The most common being the transverse rectus abdominus myocutaneous flap (TRAM). The parent blood vessels to these myocutaneous flaps arise on the deep surface of the muscle and supply the overlying skin and fat via musculocutaneous perforators: By meticulous dissection of these perforating vessels as they course through the muscle, flaps composed of skin and fat alone may be harvested from various anatomic areas without the need to sacrifice muscle at the donor site.
Advantages of muscle preservation include minimal or no loss of muscle function, markedly decreased hernia formation, decreased postoperative pain, and a shortened hospital stay. The main drawback of perforator flaps is that meticulous microvascular technique is required and may lengthen the operative time. Despite this drawback, perforator flaps provide many potential donor sites, including the lower abdomen, upper and lower buttock, back, and lateral thigh. The determination of which flap to use is based on the location of the most desirable donor tissue on each individual patient.
Deep inferior epigastric perforator flap (DIEP)
Like the TRAM, the DIEP uses redundant tissue from the lower abdomen to reconstruct the breast. The DIEP flap is usually based on one to three perforators arising from the deep inferior epigastric vessels. The DIEP flap may be substituted for the free TRAM flap in all instances and provides the added benefit of preserving the abdominal musculature and the covering
sheath, which decreases the donor site complications such as abdominal hernias and bulges. Aesthetically, most patients feel that their abdomen looks better postoperatively than it did preoperatively.
Due to the large amount of tissue available, the DIEP flap is particularly suited for simultaneous bilateral breast reconstruction. By harvesting
only skin and fat, the DIEP flap avoids the use of a tight fascial closure or synthetic mesh. This allows the patient to ambulate on the first postoperative day with minimal analgesic requirements. Typically,' the patient is in the hospital for only three to four days. Approximately 80% of patients seeking breast reconstruction are candidates for the DIEP
flap technique. See figures 1-2.
|FIGURE 1: Illustration of the anastomoses of the internal mammary artery and a unilateral DIEP flap. FIGURE 2:The DIEP flap is supplied by the deep inferior epigastric artery, a branch of the external iliac artery.|
Thoracodorsal artery perforator flap
This procedure transfers skin and fat from the back without sacrificing the latissimus dorsi muscle, thus preserving function. The flap is based on proximal musculocutaneous perforators of the thoracodorsal artery and vein. This is similar to the autogenous latissimus dorsi method of breast reconstruction, but without the transfer of any muscle. The thoracodorsal artery perforator flap provides autogenous reconstruction without the need for microvascular anastomosis or a synthetic breast implant. The donor site morbidity should be significantly decreased because the latissimus dorsi muscle is spared.
Moderately obese patients are best suited for this procedure because they generally have enough redundant tissue on their upper back to reconstruct the breast. A skin island is marked out over the proximal latissimus muscle using a Doppler probe to locate the perforators. After identification of the perforating vessels, the proximallatissimus muscle is split in the direction of
its fibers. Loupe magnification is used to dissect the perforating artery and vein to the submuscular branches of the thoracodorsal artery and vein. Care must be taken to avoid injury to the thoracodorsal nerve to preserve muscle function. This results in a vascular pedicle length on approximately 15 centimeters. The skin and fat flap is then passed through the opening in the muscle and rotated anteriorly for breast reconstruction.
Lateral thigh perforator flap
The tissue for this flap is harvested from the "saddle bag" area of the lateral thigh. This flap is based on the tensor fascia lata musculocutaneous perforator vessels. The parent vessels are the lateral femoral circumflex vessels. Similar to other perforator flaps, the technique avoids muscle sacrifice, which decreases the donor site contour deformity. However, secondary liposuction is often necessary for optimal lateral thigh contour.
Gluteal Artery Perforator (GAP) Flap
In approximately 20% of patients presenting for breast reconstruction, the lower abdomen is not a suitable donor site. In these patients, the buttock
is an excellent donor area for autogenous reconstruction. Even in young, thin patients, there is generally enough tissue available on the buttock
to reconstruct a breast. The use of a GAP flap, based on the superior or inferior gluteal artery perforators, results in a scar that is largely invisible to the patient.
The GAP flap differs from previously described myocutaneous flaps by eliminating the muscle component and providing a longer vascular pedicle. During the operation, the patient is placed in the lateral decubitis position
to harvest the flap. After the flap is harvested, the patient is repositioned supine for the microvascular anastomosis. Donor site morbidity is minimal, with ambulation on the first postoperative day and discharge on the fourth day. Occasionally, donor site seromas form, but the incidence of seromas has decreased with the use of compression garments. See figures 3-4.
|FIGURE 3: Postoperative illustration of a GAP flap. |
FIGURE 4: The anatomy of the GAP flap and the underlying gluteal musculature.
Although autogenous reconstruction accounts for less than half of the breast reconstructions performed annually, this method is gaining popularity. Previously described myocutaneous flaps, such as the TRAM flap, have the advantage of avoiding the use of prosthetic materials. The perforator flaps described in this article have the added advantage of avoiding muscle and fascia sacrifice. This translates into significantly decreased donor site morbidity, including a lower incidence of postoperative hernia, decreased postoperative pain, shortened hospital stay, shortened operative time, and decreased cost when compared to other forms of autogenous breast reconstruction.
Essentially, all patients are candidates for reconstruction with perforated flaps. Because of the multiple donor sites available, the surgeon is able to make more individualized decisions regarding donor site selection, taking into account the patient's own wishes and particular body shape. This provides for an increased level of patient satisfaction, with both the process of reconstruction and the final result.
Perforator flaps are the procedure of choice for breast reconstruction at Louisiana State University Health Sciences Center. Over the past 11 years, over 1,400 breasts have been reconstructed with these techniques.
About the authors
Robert Allen, MD, is chief of plastic surgery at Louisiana State University Health Sciences center in New Orleans and was a presenter at the 2003 AST Annual Conference in New Orleans. His special interest is microsurgical breast reconstruction. He is a pioneer in the world of breast reconstruction and performs over 300 breast surgeries annually. Eileen Black, MD, is a
plastic surgery resident at LSUHSC, and Nicholas Jones is a senior medical student.