History

Although microsurgery has traditionally served a reconstructive role in plastic surgery, it has evolved into an important modality for difficult aesthetic problems. The goals of correcting facial asymmetry center on restoring the underlying skeletal framework and recruiting soft tissue bulk. Prior to microsurgery, patients would undergo correction of the skeletal support with bone or cartilage grafts followed by soft tissue enhancement with local tissue recruitment, dermal fat grafts, synthetic or autologous fillers in a single or staged procedure. The use of microvascular free flaps allows a large volume of soft tissue with an osseous component (if necessary) to be reliably transferred to the face in a single stage.

There have been multiple techniques described for restoration of facial symmetry using microvascular free flaps. In 1980, Upton et al. described the use of a free omental flap to restore facial contour. Other groups have described the use of free groin flaps, scapular flaps, parascapular flaps and superficial inferior epigastric flaps. The parascapular flap offers several advantages in comparison to other flaps. The pedicle is long and reliable, fascial extensions can be utilized to improve facial contour, an osseous component can be incorporated into the flap, and there is minimal donor site morbidity.

Physical evaluation

Anatomy

The parascapular flap is a fasciocutaneous flap based on the circumflex scapular vessels off of the subscapular system. The circumflex scapular vessels pass through the triangular space bound by the teres minor muscle superiorly, the teres major inferiorly, and the long head of the triceps laterally (Fig. 18.1A). After passing through the triangular space, the artery gives off a branch that supplies the lateral border of the scapula allowing an osseous component to the flap. The circumflex scapular artery divides into two terminal branches, a horizontal and descending cutaneous branch. There are two accompanying veins that travel with the artery. Both or just the larger vein can be used to revascularize the flap.

Fig. 18.1 Anatomy of the parascapular flap. A, The circumflex parascapular artery passes through the triangular space. The triangular space is bordered by the teres major, teres minor and the long head of the triceps. The anterior branch has both a transverse and descending branch. B, The flap can be designed in either a horizontal, vertical or oblique orientation. The only requisite is that the origin of the circumflex artery is within the flap.

Redrawn from Siebert JW, Longaker MT, Angrigiani C. The inframammary extended circumflex scapular flap: an aesthetic improvement of the parascapular flap. Plast Reconstr Surg 1997;99(1):70–77.

The cutaneous skin paddle can be either vertically or obliquely designed depending on the degree of laxity of the skin, as well as, the aesthetic desires of the patient (Fig. 18.1B). The borders of the skin paddle for traditional parascapular flaps are the triangular space superiorly, the vertebral column medially, the axilla laterally, and inferiorly to the level approximately halfway between the inferior angle of the scapula and the posterior superior iliac spine. To ensure primary closure of the donor site, the skin paddle is often limited to a width of 10 cm. We have used extended inframammary flaps for the correction of facial contour problems because the resulting donor site scar is more favorably oriented. The only requisite for any of these flaps is that the circumflex scapular vessels are contained within the base of the flap.

The superficial temporal vessels are the most common recipient vessels for the vascular anastomosis. The superficial temporal artery is the terminal branch of the external carotid artery whose origin lies within the parotid gland. It lies approximately 1 cm anterior to the tragus. Above the level of the zygomatic arch, the superficial temporal artery lies just deep to the superficial temporal fascia. The vessels are easily exposed through a preauricular incision, the same incision used to expose the recipient site in the face. It is sometimes necessary to follow the vessels deep into the parotid if the vessels are not adequate superiorly. If the superficial temporal vessels are not adequate, there may be the need to extend the preauricular incision into the neck or better to make an additional transverse incision in the neck.

Technical steps

The areas of deficiency are marked with the patient in the upright position. Care is taken to specifically mark areas where increased augmentation is necessary and where the flap requires tapering (Fig. 18.2). The maximal width of the soft tissue deficiency in the face will correspond to the width of the skin paddle of the flap.

Fig. 18.2 A, Preoperative view of an 18-year-old woman with left-sided hemifacial atrophy. B, Representative diagram demonstrating the extent of the soft tissue deficiency and the proposed composite tissue required for reconstruction. C, Preoperative markings demonstrating the soft tissue defects and areas for augmentation. D, The parascapular flap anastomosed to the superficial temporal vessels prior to flap inset. The flap can be contoured by either removing flap tissue or by folding the fascial tissue upon itself.

B–D, Reproduced with permission from Longaker MT, Siebert JW. Microvascular free-flap correction of severe hemifacial atrophy. Plast Reconstr Surg 1995;96(4):800–809.

The patient is positioned on the operating room in a lateral oblique position that allows simultaneous access to both the face and the ipsilateral flap for a two-team approach. A preauricular incision is outlined extending from just above the ear superiorly to the lobule. The areas of soft tissue deficiency are injected with 0.5% lidocaine with 1 : 200,000 units of epinephrine. Skin flaps are raised in a subcutaneous plane analogous to a standard facelift. The dissection releases all of the areas requiring augmentation and extends at least 1 cm beyond the previous made markings. In addition, it may be required to dissect under the alar bases and beneath the ear lobule to correct any malposition. Following dissection of the recipient pocket, the face is packed with gauze sponges to ensure hemostasis.

The superficial temporal vessels are often located 1 cm anterior to the tragus. These vessels are exposed through the same preauricular incision used to dissect the facial recipient site. As previously mentioned, the artery may need to be followed into the parotid gland and if it still remains inadequate, a separate incision may be required to find suitable recipient vessels in the neck.

Dissection of the parascapular flap can occur simultaneously. The triangular space is identified and a Doppler probe is used to identify the origin of the circumflex scapular vessels and the terminal horizontal and vertical branches. An ellipsoid skin paddle is marked in a vertical or oblique direction depending on the desired length and is most commonly limited to a width of less than 10 cm to ensure primary closure. If an extended length of tissue is required, the flap can be extended to the inframammary region based on anterior branches of the circumflex scapular artery and up onto the shoulder. These extensions become necessary when soft tissue augmentation is required both superiorly and inferiorly to the level of the anastomosis.

Harvesting of the flap occurs in a caudad to cephalad direction. After the skin is incised, dissection occurs down to the deep fascia. Extensions of the dorsal thoracic fascia are dissected as needed to precisely contour the flap. Subfascial dissection begins distally and carefully proceeds in a retrograde fashion. The pedicle on the deep surface is identified and dissection is carried back to the takeoff of the thoracodorsal pedicle. The circumflex vessels are individually isolated and ligated. Hemostasis is achieved and the donor site is closed in layers over closed suction drains.

The flap is brought to the face and draped in the desired orientation. The circumflex parascapular vessels are anastomosed to the superficial temporal vessels. The skin paddle is de-epithelialized and the flap is tapered to the desired contour (Fig. 18.3). The packing sponges are removed from the recipient site and the flap is stretched out within the facial pocket. The flap is secured around the anastomosis and is also sutured to the periosteum of the zygoma and infraorbital rim to minimize downward migration of the flap. The fascial extensions are secured to the overlying skin with through and through nylon sutures tied over petroleum gauze bolsters (Fig. 18.4). Final insetting and contouring of the flap is confirmed with the patient in the sitting position. The flap is monitored clinically by Doppler signal analysis over the pedicle anastomosis. The facial flap is closed over a closed suction drain placed in the subcutaneous plane.

Fig. 18.3 A, Schematic of a customized parascapular flap. The dermis, fat and fascia of the flap are used to augment the areas of soft tissue deficiency to various degrees. B, This intraoperative photograph is a representative flap after de-epithelialization and custom contouring.

A, Redrawn from Longaker MT, Siebert JW. Microsurgical correction of facial contour in congenital craniofacial malformations: the marriage of hard and soft tissue. Plast Reconstr Surg 1996;98(6):942–950. B, Reproduced from Longaker MT, Siebert JW. Microsurgical correction of facial contour in congenital craniofacial malformations: the marriage of hard and soft tissue. Plast Reconstr Surg 1996;98(6):942–950.

Fig. 18.4 Diagrammatic illustration of the final flap inset using bolster dressings to secure the flap to the overall lying skin.

Redrawn from Longaker MT, Siebert JW. Microvascular free-flap correction of severe hemifacial atrophy. Plast Reconstr Surg 1995;96(4):800–809.

Postoperative care

The patient should be monitored either in the recovery room or in a specialized unit with nurses trained to care for free flaps. The patients should receive a rectal aspirin in the recovery room and this should continue orally for 1–3 months. The patient should be given adequate hydration to maintain a minimum urine output of 1 mL/kg/hour. Blood pressure should be maintained with a mean arterial pressure greater than 60 mm Hg. Drops in systolic blood pressure should be corrected with fluid boluses or the administration of blood products. The use of vasopressors should be avoided unless absolutely necessary. This needs to be mentioned to your anesthesia colleagues prior to the case as well. In our experience, the majority of our flaps are not monitored. In the event a flap requires monitoring, the flap is monitored every fifteen minutes for two hours, every half hour for the next two hours, and then every one hour thereafter. The average hospital day for these patients is 2–3 days. The facial drain is removed prior to discharge and the donor site drains are removed on day seven along with the facial bolsters and sutures. Ancillary procedures are often necessary to recontour the flap; however, they are mostly minor and are often deferred until the patient is at least five months postoperative (Figs 18.5, 18.6).

Fig. 18.5 A, C, Preoperative views of a 26-year-old female with left-sided hemifacial atrophy. B, D, Postoperative appearance of the patient (2 years later) after parascapular flap.

Reproduced with permission from Saadeh PB, Chang CC, Warren SM, et al. Microsurgical correction of facial contour deformities in patients with craniofacial malformations: a 15-year experience. Plast Reconstr Surg 2008;121(6):368e–378e.

Fig. 18.6 A, C, Preoperative views of a 19-year-old with bilateral facial atrophy as a result of systemic lupus. The patient underwent staged reconstruction with extended parascapular flaps. B, D, Postoperative views of the patient 7 years since surgery.

Reproduced with permission from Saadeh PB, Chang CC, Warren SM, et al. Microsurgical correction of facial contour deformities in patients with craniofacial malformations: a 15-year experience. Plast Reconstr Surg 2008;121(6):368e–378e.

Complications

The most serious complication of this procedure is microvascular thrombosis and flap loss. Doppler signal loss requires emergent exploration and vessel revision as necessary. Hematomas also require urgent evacuation. As with all free flaps, hematomas are often secondary to anastomotic venous occlusion. Any loss of the facial skin flap loss is treated with local wound care. Facial nerve injuries can occur, but are rare. Most are observed for a minimum of six months unless identified intraoperatively. Facial nerve repair is best performed at the time of surgery if recognized. Long-term complications include inadequate augmentation and recurrent atrophy. Local flaps can be used to correct small areas inadequate fill; however, a second free flap rarely may be required for recurrent facial atrophy (e.g. superficial inferior epigastric flap).