Fenestration Improves Acellular Dermal Matrix Biointegration: An Investigation of Revascularization with Photoacoustic Microscopy

Abstract

Background: Acellular dermal matrices have revolutionized alloplastic breast reconstruction. Furthering our knowledge of their biointegration will allow for improved design of these biomaterials. The ideal acellular dermal matrix for breast reconstruction would provide durable soft-tissue augmentation while undergoing rapid biointegration to promote physiologic elasticity and reduced infectious complications. The inclusion of fenestrations in their design is thought to promote the process of biointegration; however, the mechanisms underlying this theory have not been evaluated. Methods: Biointegration of standard and fenestrated acellular dermal matrices was assessed with serial photoacoustic microscopic imaging, in a murine dorsal skinfold window chamber model specifically designed to recapitulate the microenvironment of acellular dermal matrix–assisted alloplastic breast reconstruction. Photoacoustic microscopy allows for a serial, real-time, noninvasive assessment of hemoglobin content and oxygen saturation in living tissues, generating high-resolution, three-dimensional maps of the nascent microvasculature within acellular dermal matrices. Confirmatory histologic and immunohistochemical assessments were performed at the terminal time point. Results: Fenestrated acellular dermal matrices demonstrated increased fibroblast and macrophage lineage host cell infiltration, greater mean percentage surface area vascular penetration (21 percent versus 11 percent; p = 0.08), and greater mean oxygen saturation (13.5 percent versus 6.9 percent; p < 0.05) than nonfenestrated matrices by 2 weeks after implantation. By 21 days, host cells had progressed nearly 1 mm within the acellular dermal matrix fenestrations, resulting in significantly more vascularity across the top of the fenestrated matrix (3.8 vessels per high-power field versus 0.07 vessels per high-power field; p < 0.05). Conclusions: Inclusion of fenestrations in acellular dermal matrices improves the recellularization and revascularization that are crucial to biointegration of these materials. Future studies will investigate the optimal distance between fenestrations.

Meshed Acellular Dermal Matrix for Two-Staged Prepectoral Breast Reconstruction: An Institutional Experience

“…2 The meshing and fenestrations in the ADM are hypothesized to allow the free fluid to more easily egress, enhancing the effacement between the ADM graft and skin flaps, and accelerating cellular integration and revascularization via improved tissue oxygenation and fibroblast and macrophage lineage host integration. 21 22 24…”

In Vitro Characterization of a Novel Human Acellular Dermal Matrix (BellaCell HD) for Breast Reconstruction

“…Immune cells like lymphocytes, granulocytes, macrophages and mast cells, fibroblast, and myofibroblasts recolonize the original ADM during implantation in the breast reconstruction process [14]. Capsule and capillaries are formed by the fibrosis and neovascularization [17]. It should be compatible and capable of inducing the biological responses like host cell adhesion and cell proliferation with no cytotoxicity to the host tissue.…”

Understanding the Evidence and Improving Outcomes with Implant-Based Prepectoral Breast Reconstruction

“…16,20,28 Fenestrations were used in one anterior support series with the intention of increasing the surface area of the interface between patient and acellular dermal matrix to support patient tissue ingrowth. 26,42 No differences in early outcomes between acellular dermal matrix techniques can be discerned from the data reported (Table 1).…”

“…43 Meshing or fenestrating acellular dermal matrices would create potential space for native capsule formation that may increase capsular contracture rates or may simply provide points of egress for serous fluid and increase the rate of biointegration. 42 Incision location may also have an impact on wound healing outcomes, as mastectomy skin flaps are thinner centrally than they are at the inframammary fold. It has not been demonstrated yet whether differences in technique impact the complication rate of prepectoral breast reconstruction, but they are useful points to consider while designing the operation.…”