"Fat necrosis following deep inferior epigastric artery perforator flap breast reconstruction: A systematic review and meta-analysis".

Abstract

Fat necrosis has been described to affect up to 35.0% of Deep Inferior Epigastric Artery Perforator (DIEP) flap breast reconstructions. It compromises esthetic outcomes and can falsely raise concerns about cancer recurrence. This study aims to identify factors predictive of postoperative fat necrosis in reconstructed breast flaps. Following PRISMA 2020 guidelines, MEDLINE/EMBASE/CINAHL/CENTRAL databases were searched through December 4, 2024, for studies reporting the incidence of postoperative fat necrosis in DIEP flaps. Meta-analyzes were performed for variables supported by at least four comparative studies. Fixed- and random-effects models were applied to pool risk ratios (RRs) with 95% confidence intervals (CIs), using an I² heterogeneity threshold of 50%. The systematic review (SR) included 100 studies (42 eligible for meta-analyzes), representing 9704 flaps. Fat necrosis risk was reduced with intraoperative indocyanine green (ICG) fluorescence (RR 0.64, 95% CI 0.49-0.83, P=0.0008), flaps based on lateral row perforators versus medial and lateral (RR 0.59, 95% CI 0.43-0.82, P=0.001), harvesting ≥2 perforators (RR 0.68, 95% CI 0.48-0.96, P=0.03), and venous outflow augmentation with the Superficial Inferior Epigastric Vein (SIEV) (RR 0.48, 95% CI 0.28-0.84, P=0.010). Fat necrosis risk increased with unilateral versus bilateral reconstructions (RR 1.53, 95% CI 1.13-2.06, P=0.006) and BMI ≥25 (RR 1.60, 95% CI 1.05-2.43, P=0.03). Preoperative CT angiogram was not significantly associated with fat necrosis (RR 0.60, 95% CI 0.33-1.11, P=0.10). To minimize fat necrosis, surgeons should optimize perforator selection, use intraoperative ICG perfusion mapping, and augment venous outflow with SIEV anastomosis. Patients with elevated BMI or unilateral reconstructions should be counseled regarding their increased risk.