Histopathological Study of Meshed Versus Solid Sheet Acellular Dermal Matrices in a Porcine Model

Prepectoral Direct-to-Implant versus Staged Tissue Expander Breast Reconstruction: A Comparison of Complications

BACKGROUND

Direct-to-implant (DTI) reconstruction has multiple advantages over a staged tissue expander (TE) approach. However, its use may be limited by concerns of increased complications. This study is the largest series to date comparing postoperative outcomes for DTI versus TE reconstruction in the prepectoral plane.

METHODS

The authors retrospectively reviewed 348 patients who underwent 536 total immediate, prepectoral implant-based breast reconstructions between January of 2018 and December of 2021. The authors compared the presence of risk factors and the rate of six separate complications between patients who underwent DTI versus TE reconstruction up to 1 year after surgery.

RESULTS

Of 348 patients, 147 (42%) and 201 (58%) underwent TE and DTI reconstruction ( P = 0.1813), respectively. The overall infection rate was 16.4% ( n = 57). DTI patients had a significantly greater incidence of wounds ( P < 0.0001), including minor ( P < 0.0011) and major wounds ( P < 0.0053). Significantly greater mastectomy resection weights were found for DTI patients who experienced any complication ( P < 0.0076), postoperative wounds ( P < 0.0001), and major wounds specifically ( P < 0.0035). Compared with medium-thickness acellular dermal matrix (ADM), extra thick ADM was associated with significantly increased rates of infection ( P < 0.0408) and wounds ( P < 0.0001).

CONCLUSIONS

Prepectoral DTI reconstruction in patients with adequate flap perfusion may have complication rates comparable to staged TE reconstruction, apart from a higher incidence of postoperative wounds. Greater mastectomy resection weights and thickness of ADM may specifically contribute to infection and wound-healing complications. Prepectoral DTI reconstruction is encouraged in the patients with adequate flap perfusion and moderate to low mastectomy resection weights who desire comparable or smaller implant volumes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Comparative proteomic analysis of regenerative acellular matrices: The effects of tissue source and processing method

Acellular tissue matrices are used in regenerative medicine from weak tissue re-enforcement to cosmetic augmentation. However, proteomic signatures leading to different clinical outcomes among matrices are not well understood. In an attempt to investigate the effects of tissue source and processing method, we examined by liquid chromatography tandem mass spectrometry (LC-MS/MS) the proteomic profiles of 12 regulatory agency-approved acellular matrices (AlloMax, AlloDerm, CollaMend, Heal-All, JayyaLife, ReGen, Renov, Strattice, SurgiMend, Surgisis, UniTrump and Vidasis). The compositions of acellular matrices varied greatly with the number of identified proteins ranging from 7 to 106. The content of individual proteins was between 0.0001% and 95.8% according to their abundances measured by the M/Z signal intensities. Most acellular matrices still contained numerous cellular proteins. AlloMax, AlloDerm, ReGen, Strattice, SurgiMend and Surgisis retained necessary structural and functional proteins to form the extracellular protein-protein interaction networks for cell adhesion, proliferation and tissue regeneration, whereas CollaMend, Heal-All, JayyaLife, Renov, UniTrump and Vidasis had only retained certain structural collagens. Principal component analysis showed that proteomic variations among acellular matrices were largely attributed to tissue source and processing method. Differences in proteomic profiles among acellular matrices offers insights into molecular interpretation for different clinical outcomes, and can serve as useful references for rational design of regenerative bio-scaffolds.

Comparison of porcine and human acellular dermal matrix outcomes in wound healing: a deep dive into the evidence

Acellular dermal matrices (ADM) are a novel graft. The goal of this systematic review is to evaluate the evidence behind differences in human and porcine ADM, irrelevant of manufacturing method, and to determine if there is enough of an evidence base to change clinical practice. An extensive literature search was performed through MEDLINE and Embase with search terms defining a population, intervention and outcome. Title and abstract exclusion were performed with other exclusion criteria. In 191 articles were found after exclusion of duplicates, with only 29 remaining following exclusions. Ten studies were found to have level I and II evidence (I=3, II=8), of which two were histopathological, one was an animal model, one was a systematic review, and six were clinical. The remaining studies were reviewed and considered for discussion, but did not hold high enough standards for medical evidence. Strong clinical evidence already exists for the use of human ADM, but questions of access, cost, and ethics require consideration of a xenograft. Histopathologically, evidence suggests minimal long-term differences between human and porcine ADM, although there is a short acute immune response with porcine ADM. Clinically, there is limited difference in outcomes, with a small range in effect of different ADM preparations. Considering the effectiveness of ADM in wound healing, more high-level research with appropriate statistical analysis to facilitate a future meta-analysis is recommended to justify a transition from human to porcine ADM.

A Sustainable Approach to Prepectoral Breast Reconstruction Using Meshed Acellular Dermal Matrix

Background:

Prepectoral implant-based breast reconstruction provides an alternative to submuscular reconstruction, but the increased acellular dermal matrix (ADM) required has the potential to lead to increased costs and decreased supply of this limited-resource material. We present a method for prepectoral reconstruction utilizing skin-graft meshing techniques to increase the surface area of usable ADM.

Methods:

Forty-four patients underwent this technique from February 2019 to February 2020. Patient characteristics, operative details, and outcomes, including complications and patient satisfaction utilizing the BREAST-Q, were analyzed. Cost analysis relative to projected cost of nonmeshed techniques was performed.

Results:

There were 20 unilateral and 24 bilateral procedures, for a total of 68 breast reconstructions. Mean age was 45.9 years (32–71). Mean implant volume was 485 cm³ (265–800), and one sheet of ADM was used for each breast with an average surface area of 161 cm². Median follow-up was 350 days (212–576). Minor complications included an infection treated with oral antibiotics. Major complications included one axillary hematoma and one delayed implant loss. One patient underwent revision for asymmetry. Mean BREAST-Q score was 47.4/60. Cost ranged from $4113 to 5025 per breast, compared with the projected $9125–18250 per breast for other techniques in the literature.

Conclusions:

In contrast to previously described uses of ADM in prepectoral reconstruction, meshing maximizes resource utilization by expanding the coverage of a single sheet. Early findings demonstrate minimal complications and high patient satisfaction, suggesting the approach has potential to provide the benefits of prepectoral reconstruction while responsibly preserving product availability and tempering healthcare costs.

Meshed Acellular Dermal Matrix in Immediate Prepectoral Implant-based Breast Reconstruction

Prepectoral implant placement has many potential advantages in immediate breast reconstruction. Acellular dermal matrices (ADMs) are commonly used in these surgeries. ADM meshing may enhance integration, decrease seroma and infection rates, and reduce surgical costs.

METHODS

This was a retrospective, single-center study of 49 women (71 breasts) undergoing immediate, prepectoral, implant-based breast reconstruction with 2:1 meshed, bovine-derived ADM (SurgiMend). Outcomes were compared against those of 77 patients (105 breasts) undergoing a similar procedure but with partial subpectoral implant placement.

RESULTS

In the prepectoral group, the mean age was 49.1 years and mean body mass index was 24.7 kg/m². There were no significant differences in baseline characteristics versus the partial subpectoral control group. Mean follow-up was 18.6 months (prepectoral) and 21.3 months (partial subpectoral). Mean time to drain removal was reduced in the prepectoral group (6.5 versus 8.5 days; P < 0.001). Rates of minor and major complications with prepectoral implant placement were 15.5% and 11.3%, respectively - similar to partial subpectoral placement (15.2% and 14.3%) (overall P = 0.690). Capsular contracture and explantation were associated with radiation therapy, and rates were similar between groups.

CONCLUSIONS

Prepectoral implant placement with meshed ADM is a safe and reproducible alternative to partial muscle coverage with meshed ADM. Recovery may be easier and animation deformity avoided. It could therefore become the standard of care for implant-based breast reconstruction.

Clinical experience with Surgimend in breast reconstruction: an overview

In the field of breast reconstruction, products and techniques are continuing to evolve to ensure good clinical and quality outcomes. This article reviews the published literature regarding the use of fetal bovine-derived acellular dermal matrix (SurgiMend, SurgiMend PRS and SurgiMend PRS meshed), focusing on safety, clinical outcomes and surgical techniques.