The versatility of the SIEA flap: a clinical assessment of the vascular territory of the superficial epigastric inferior artery

Summary Following the TRAM and the DIEP the SIEA flap is the next logical step to reduce the donor site morbidity in autologous breast reconstruction. The vascular axis of the SIEA flap, however, is completely different from the deep epigastric pedicle, on which previous lower abdominal flaps were based. Therefore, a mapping of the vascular territory, which can be reliably harvested on this pedicle, seems mandatory before this new technique can become established. Aim To chart the angiosome of the superficial inferior epigastric artery with regard to breast reconstruction and to evaluate the random extension of the vascular territory, which can be reliably raised on this pedicle. Study design Clinical, prospective study in a university-affiliated department of plastic surgery. Patients Ten patients undergoing autologous breast reconstruction with the superficial inferior epigastric perforator flap and five patients undergoing aesthetic abdominoplasty with isolation of the abdominal flap on the superficial epigastric vessels. Material and methods After isolation of the abdominal panniculus on a single superficial inferior epigastric artery pedicle, the flap was divided in the four conventional zones according to Hartrampf. Perfusion in each of the four zones was measured on the table using the technique of dynamic laser-fluorescence videoangiography. Results Perfusion of Hartrampf Zone III occurred first (25 s post-injection) and the perfusion index amounted median 89% of reference. Perfusion of Zone I occurred median 5 s later and the relative perfusion was 80%. Perfusion of the contralateral zones II and IV was dramatically reduced to 8% and zero, respectively, and this reduction was statistically significant ( p < 0.0001). Conclusion The true angiosome of the superficial epigastric artery is located laterally on the ipsilateral hemiabdomen. Its random extension is unreliable and ranges most frequently only to the midline. Based on the results of this study, survival of the skin and subcutaneous fat taken laterally to the border of the contralateral rectus sheath seems questionable. Therefore, the versatility of the SIEA flap for autologous breast reconstruction seems limited when compared with the conventional methods based on the deep inferior epigastric system.