Pre‐hydrated sterile acellular dermal matrix allograft in breast reconstruction: review of a single unit's experience
Traditionally, implants or tissue expanders are inserted into a sub‐musculofascial pocket. Pectoralis major muscle is elevated to create a subpectoral pocket. To achieve sufficient expansion inferiorly and medially, the inferomedial attachment of pectoralis major is detached. To allow sufficient ptosis, rectus abdominis fascia and lateral chest wall fascia are elevated and released. Serratus anterior muscle and its fascia are elevated to create a robust fascial cover laterally.3 Even with such extensive dissection, a complete submuscular implantation can lead to preferential expansion of the upper pole of the implant with poor inframammary fold definition and thus poor cosmetic outcome.4 Alternative options include incomplete muscular cover where the lower pole is only covered by the skin flap (‘dual plane positioning’).5 This allows expansion of the inferior pole but often leads to inferior migration of the implant and obvious rippling. A number of techniques are described to improve implant cover in the lower pole. In patients with excess skin, it may be possible to use an inferior dermal flap in combination with a wise pattern skin reduction. Regional flaps, such as the latissimus dorsi flap, provide excellent soft tissue cover but significantly increase the operative time and are associated with some donor site morbidity. Number of biological and synthetic materials are also available to cover the lower pole of implants such as porcine submucosal tissue (Biodesign, Cook Biotech, Inc., Bloomington, IN, USA), acellular bovine pericardium (Veritas, Synovis Life Technologies, Inc., Saint Paul, MN, USA) and synthetic materials (Ti LOOP Bra, PFM Medical Titanium GmbH, Nuremberg, Germany). More recently, ADMs have evolved as a popular alternative for coverage of the lower pole of the implant in breast reconstruction. ADM includes a group of immunologically inert dermal replacement products created from decellularized cadaveric or xenographic (porcine or bovine) skin.
A number of allograft products are available for clinical use, and include AlloDerm (LifeCell Corp., Branchburg, NJ, USA), DermaMatrix (Synthes, Inc., West Chester, PA, USA), Strattice (LifeCell Corp.), SurgiMend (TEI Biosciences, Inc., Waltham, MA, USA), Flex HD (FHD, Ethicon, Inc., Somerville, NJ, USA and Musculoskeletal Transplant Foundation, Edison, NJ, USA), AlloMax (Bard, Warwick, RI, USA) and AlloDerm Ready to Use (LifeCell Corp.). They differ in their decellularizing processes, storage and rehydration protocols and sterilization methods.6 The materials act as a biological scaffold for neovascularization and fibroblast infiltration. ADM is claimed to integrate into native tissue by 3 months due to ingrowth of new blood vessels and infiltration by active fibroblasts.7 Absence of giant cell foreign body reaction on this tissue also demonstrates that ADM is mostly immunologically inert.7
Use of ADM has become a common adjunct in modern implant based breast reconstruction following earlier descriptions by Breuing and Colwell and Salzberg et al.8 The procedure is more straightforward than creating a complete sub‐musculofascial pocket. Only a subpectoral pocket is created to cover the upper two quadrants of implant.