The Value of BMI for Breast Reconstructions with the SIEA Flaps: Predicting the Ideal Intercostal Plane for the End-to-End Microvascular Anastomosis and the Possibility of Utilizing the TDA as a Salvage Recipient Choice

Background The superficial inferior epigastric artery (SIEA) diameter and the matching degree between the donor and the recipient arteries in terms of diameter are key factors affecting the outcome of the procedure in breast reconstructions with the SIEA flaps. A diameter of the SIEA ≥ 1.5 mm and a matching degree ≥ 1:2 (50%) of the diameters of the donor and the recipient arteries are recognized standards for the SIEA and the internal mammary artery (IMA) to achieve an end-to-end anastomosis. However, further refinements of the population characteristics and the ideal microscopic anastomosis intercostal planes are currently lacking for the criteria. Methods In this study, based on 20 sides of hemiabdomen with computed tomography angiography (CTA) data suggesting the presence of the SIEA, we analysed the diameters of the donor and the recipient arteries as well as their matching degrees. The correlations between the parameters above and body mass index (BMI) were assessed. Based on the lower bounds of the 95% confidence intervals of the matching degrees and the two critical nodes of 50% and 67%, we theoretically evaluated the possibility of an end-to-end anastomosis of the SIEA and the IMA at different levels of BMIs and intercostal spaces, and predicted the possible intraoperative management measures for the SIEA. Results The SIEA diameter, the thoracodorsal artery (TDA) diameter, and the diameters of the IMA at the 2nd to the 5th intercostal levels were positively correlated with the BMI ( p