Acellular dermal matrix fenestrations and their effect on breast shape

Background Acellular dermal matrices (ADMs) are increasingly being utilized in primary and secondary breast reconstruction as they confer several advantages, including soft tissue enhancement at the inferolateral pole of the breast. The senior authors have added fenestrations to ADMs to allow for more rapid expansion and improved breast aesthetics. The purpose of this study is to describe the benefits of ADM fenestration using a mathematical formula as a proof of concept for the effects of these modifications on breast shape. Methods The aggregate effect of symmetrically arranged fenestrations on the ADM’s mechanical properties is explained by a uniform reduction in the effective Young’s modulus of the graft in a direction perpendicular to the chest wall in the area of graft fenestration. Asymmetric reduction of the Young’s modulus is achieved by concentration of the fenestrations at either the cephalic or caudal ends of the ADM. Results The relaxed Young’s modulus facilitates an increased deflection of the ADM from its resting, unaltered state under the weight of the implant or tissue expander and is modeled using a one-dimensional boundary equation. The reduced inferior pole tension allows for enhanced expansion under the weight of the implant or tissue expander. The effects of asymmetrically arranged fenestrations are similarly modeled and appear to afford the surgeon greater precision in controlling inferior pole characteristics. Conclusions Acellular dermal matrix fenestration improves aesthetic outcome by facilitating greater inferior pole expansion. Mathematical models are provided to describe the modifications and elucidate the mechanism behind their effect on breast shape. Level of Evidence: Not ratable © Springer-Verlag Berlin Heidelberg 2015.