Improving long-term projection in nipple reconstruction using human acellular dermal matrix: an animal model.

Reconstructed nipples rapidly lose projection. We describe the use of human acellular dermal matrix (ADM) to improve long-term projection of nipple flaps. Athymic rats were randomized to 3 groups; each received 2 nipples: bell flap (control, n = 16 nipples), bell flap with a cylinder of implanted ADM (n = 24), or bell flap with intraflap injection of micronized ADM (MADM) (n = 10). Seven of 24 ADM nipples extruded (30%). By 12 weeks, the control nipples maintained 44% of initial projection compared with 70% for ADM nipples (P = 0.000025). The MADM nipples maintained 49% of initial projection after 12 weeks (P = 0.55 compared with control). No MADM nipples extruded. ADM grafts maintain long-term projection better than local tissue flaps alone. We hypothesize that MADM may limit extrusion and allow for serial injection of nipples. Based on the promising results of this study, clinical trials are warranted using human ADM and/or human MADM for nipple reconstruction.