AB047. SOH26AB_0435. Superficial inferior epigastric artery (SIEA) flap for autologous breast reconstruction: a cohort study with technical pearls

Background: Autologous abdominal tissue transfer remains the gold standard for breast reconstruction due to its natural aesthetic. The superficial inferior epigastric artery (SIEA) flap is the least invasive abdominal option, avoiding rectus muscle and fascial violation, but uptake is low because of concerns about arterial complications and donor site morbidity. This study aimed to review institutional experience with SIEA flaps in carefully selected patients and highlighted technical strategies to optimise outcomes.

Methods: A retrospective review was conducted of all abdominally based free flap breast reconstructions from January 2020 to September 2025. Patients were considered for SIEA reconstruction when preoperative computed tomography angiography (CTA) demonstrated a dominant superficial system (SIEA ≥1.5 mm) and inadequate deep inferior epigastric perforators (DIEPs). Demographics, comorbidities, adjuvant therapy, operative details, and complications were recorded and descriptively compared with contemporaneous DIEP flaps. Categorical variables were analysed with Fisher’s exact test (P<0.05).

Results: A total of 170 flaps were performed in 161 patients: 165 DIEP (97%) and 5 SIEA (3%). All SIEA flaps were immediate and unilateral. Mean age was 48.4 years (SIEA) vs. 53.5 years (DIEP). Length of stay averaged 10 days for SIEA patients and 8 days for DIEP patients. No SIEA flap experienced arterial insufficiency, venous thrombosis, or loss. Donor-site seroma occurred in 1/5 SIEA cases (20%) vs. 3/165 DIEP cases (1.8%) (P=0.058). No abdominal dehiscence or hernia occurred in the SIEA group. Overall complication rates were 20% (SIEA) vs. 5.5% (DIEP) (P=0.3).

Conclusions: In highly selected patients with favourable superficial arterial anatomy, SIEA flaps can provide successful breast reconstruction with minimal abdominal morbidity. Optimal outcomes rely on careful patient selection, meticulous technique, and appropriate recipient vessel choice. Although the seroma risk may be higher, the absence of abdominal wall weakness is a notable benefit. Larger studies are needed to clarify comparative performance.

Keywords: Superficial inferior epigastric artery flap (SIEA flap); breast reconstruction; post-operative complications; autologous reconstruction; deep inferior epigastric perforator flap (DIEP flap)