No abstract

T he majority of autologous free flap breast reconstruction uses tissue from the lower anterior abdominal wall. Traditionally, this involved harvesting the entire ipsilateral or bilateral rectus abdominus muscles while incorporating them into the transverse rectus abdominus flap (TRAM flap). Recently, lower abdominal wall flap elevation has evolved from complete rectus abdominus muscle resection to limited muscle harvest and finally to perforator flap harvest. The deep inferior epigastric artery perforator (DIEP) flap is now considered to be one of the least debilitating harvest techniques routinely used in breast reconstruction. This perforator flap uses the deep inferior epigastric artery and venea comitantes to perfuse varying degrees of the lower abdominal wall skin and fat, without intentional harvest or destruction of any rectus abdominus muscle. However, a DIEP flap harvest damages the anterior rectus fascia in all cases, and intermittently transects or causes significant neuropraxia of the intercostal nerves, particularly if more than one perforator is required. In addition, the longer the vascular pedicle harvest, the longer the fascia incision, and the greater the chance of intercostal nerve damage. This can lead to increased pain, lower abdominal wall bulging and hernia development (1-4).The superficial inferior epigastric artery (SIEA) flap uses a medially located vein -the superficial epigastric artery -and, rarely, its associated venea to reliably perfuse the ipsilateral hemiabdominal wall skin and fat. The anterior abdominal wall fascia is left intact in all cases. This technique all but eliminates the possibility of an iatrogenic anterior abdominal wall hernia. Pain is also typically decreased because the muscle, fascia and nerves to the anterior abdominal wall are left intact. Despite the potential benefits, the use of this flap has been limited in breast reconstruction when compared with the deep inferior arterybased flaps. Cited reasons for this include: that typical perfusion only supports an ispilateral hemiabdomen (3,5-7); the SIEA vessels have been cut preoperatively in many cases due to previous pfannenstiel incisions; and the diameter of the artery is believed to be of insufficient size to reliably complete a successful microvascular anastomosis. The highest reported rate of use of the SIEA flap versus the DIEA-based flaps has been in the 30% range (3,5,8,9). Yet, the presence of the SIEA and venea, and the SIEV of sufficient calibre has been documented in anatomical studies to be available in nearly 75% of cases (10).Over the past 10 years, our use of the SIEA flap has progressed from a rare event to more than 35% of all abdominal wall-based autologous breast reconstructions performed at our institution. The change in harvest technique and the algorithm for selection are described below with video documentation of the technique. Lower abdominaL waLL-based autoLogous tissue harvest aLgorithmThe algorithm for deciding whether to use a SIEA flap is based on the following considerations. Fi...