Superficial Inferior Epigastric Artery

arteria epigastrica inferior superficialis

The superficial inferior epigastric artery (SIEA) is a small and inconstant branch of the femoral artery arising just below the inguinal ligament, ascending superficially through the subcutaneous fat of the lower abdomen toward the umbilicus. When present and of adequate calibre (greater than 1.5 mm), it provides a true superficial pedicle for the SIEA flap in breast reconstruction, avoiding any rectus muscle or fascia violation.

Region: Abdomen

Clinical Relevance

Clinical Notes

The SIEA flap is the ideal abdominal free flap for breast reconstruction when the SIEA is present and adequate, as it spares both the rectus muscle (TRAM morbidity) and the rectus fascia (DIEP morbidity). However, the SIEA is absent or too small (less than 1.5 mm) in approximately 60-70% of patients, making it unreliable as a primary option. Pre-operative CTA assesses SIEA calibre. When used, the SIEA flap is technically more challenging due to the shorter and smaller pedicle but produces the least abdominal wall morbidity of all abdominal flap options.

Pathology

Common Injuries & Conditions

SIEA Flap Selection Criteria for Breast Reconstruction

Pre-operative CTA identifying a superficial inferior epigastric artery of diameter 1.5 mm or greater at its femoral origin allows planning of an SIEA flap with the least abdominal wall morbidity; smaller calibre vessels require conversion to DIEP flap intraoperatively if inset perfusion is inadequate on test-clamp assessment.