Commentary on: One-Stage Implant-Based Breast Reconstruction With Polyurethane-Coated Device: Standardized Assessment of Outcomes

See the Original Article here.

This study reported on the authors’ experience of using polyurethane implants for prepectoral direct-to-implant (DTI) breast reconstruction, focusing on safety and feasibility.¹ A total of 63 patients were included in this prospective study, with 74 reconstructions. All patients underwent nipple-sparing mastectomy and immediate breast reconstruction with micro-polyurethane foam–coated anatomic implants. The authors used standardized assessments to report preoperative patient characteristics and postoperative complications. At a median follow-up of 12 months, they reported the following complications: seroma (5.4%), hematoma (2.7%), infection (4%), unplanned readmission (6.7%), implant loss within 3 months (6.7%), and rippling/edge visibility (8.1%). There were no cases of capsular contracture or implant rotation or malposition. The authors concluded that polyurethane-coated implants may prevent rotation and malposition and capsular contracture in the short term but unplanned readmission and implant loss rates may be slightly higher.

Polyurethane foam coating of silicone implants was introduced in 1968, followed by introduction of implant texturization 2 decades later. The aim of the design was to reduce incidence of capsular contracture. It is now well-established that the polyurethane layer does indeed mitigate the risk of capsular contracture.^2-4 In addition, the polyurethane surface adheres to breast tissue, eliminating dead space and preventing fluid accumulation, and stabilizes the implant. These qualities reduce the risk of seroma and implant rotation and malposition, respectively. The results from this study further contribute to the evidence regarding the beneficial effects of polyurethane coating.

Dr Maxwell, along with Dr Rod Hester and his colleagues at Emory University, Atlanta, GA, had perhaps the largest clinical experience in the United States with the use of polyurethane-coated implants (in the mid to late 1980s). They likewise found and reported favorable outcomes, citing similar findings as the authors of this paper, with implant stabilization and reduced capsular contracture (immobility with softness). This led them to use polyurethane-coated implants as their implant of choice in most clinical cases, until their removal from the US market in 1991.^4,5

Because the benefits of polyurethane-coated implants mirror those of acellular dermal matrix (ADM), the question arises as to whether these implants could replace ADMs. Interestingly, the idea of wrapping the implant (or expander) with ADM originated from coating of the implant with polyurethane and was suggested by Dr Maxwell in 2008.⁶ The authors state that the use of ADMs essentially amounts to using a second device, which in turn prolongs procedure time and costs. We respectfully disagree with this statement. In our experience, preparing and suturing ADMs would not add significantly to the procedure time. The authors recruited the serratus and the rectus abdominis fascia for lateral, medial, and inferior implant support, which would also add to the procedure time. If ADM were to be used for implant wrapping, then there would be no necessity for fascial recruitment, because the ADM would provide implant support. Fascial recruitment violates the muscle fascia and can lead to soreness and stiffness. Stiffness and soreness were reported in 40% of the breasts during the early postoperative period in this study; some of this was likely due to fascial recruitment. Although patients who have had ADM do also report soreness, it is due to the mastectomy (that is, violating areas that should not have been) or from suturing the ADM.

Although cost is an issue with the use of ADM, it must be considered within the framework of long-term benefit, aesthetic outcome, and the psychological peace of mind that comes with having a biological material rather than a synthetic polyurethane foam material in one’s body. There is, however, no evidence of a causal relationship with malignancy or toxicity with polyurethane implants.⁴ After implantation, the polyurethane is biodegraded and disappears within 2 to 5 years after surgery.⁴ After 5 years there may be no macroscopic evidence of polyurethane, but microscopic presence of polyurethane has been noted in capsules up to 30 years after the original operation. The complete disappearance of polyurethane can lead to the emergence of capsular contracture.^4,7 There is therefore a risk of long-term capsular contracture with polyurethane-coated implants.

There are also other concerns with polyurethane-coated implants, namely the risks of delamination and breast implant–associated anaplastic large cell lymphoma (BIA-ALCL). Delamination of the polyurethane coating exposes the surface texturing of the implant. Surface texturing has been implicated with the development of BIA-ALCL.⁸ In addition, there is the possibility of a risk of BIA-ALCL from the polyurethane coating itself, although there is currently very little evidence for this association apart from an Australian study.⁹ Delamination may also expose bacteria harbored within the polyurethane microcapsules. Bacterial contamination around breast implants has been implicated with the development of biofilm and capsular contracture.¹⁰ Delamination, however, appears to have been reported mostly with the Silimed polyurethane implants rather than Polytech implants, suggesting that durability of polyurethane attachment to the implant surface may depend on the method of attachment.⁹

Delamination is not unique to polyurethane-coated implants, because ADM-wrapped implants can also delaminate. However, ADM delamination and its revascularization into the subcutaneous (underside) of the mastectomy flap creates a clinically important, receptive, recipient space for fat grafting, which improves the long-term soft tissue cover of the implant, minimizing the appearance of visible ripples, as was reported here. Furthermore, ADM does not carry a risk of BIA-ALCL.

A surprising result from this study was the high incidence of unsatisfactory cosmetic results. This contrasts with other published reports of a generally superior aesthetic outcome and greater patient satisfaction with polyurethane implants.⁴ The authors reported that about 30.7% of patients had unsatisfactory cosmetic results and requested a delayed procedure. The reasons for the unsatisfactory cosmetic results were not discussed, although it was mentioned that 11% of patients had major asymmetry and 8% of breasts exhibited rippling and edge visibility. Interestingly, 32 years ago in a plastic and reconstructive surgery “Discussion” article, Dr Maxwell noted the unsightly appearance of skin rippling following subcutaneously placed polyurethane-coated implants for breast reconstruction as one of its main negative attributes.¹¹ Fortunately, implant rippling, wrinkling, and edge visibility can often be resolved with autologous fat grafting.

A couple of minor points to note. There appears to be a calculation error pertaining to the percentage of patients who had unsatisfactory aesthetic outcomes. The authors stated that 16 patients had unsatisfactory aesthetic outcomes, which should be 25.4% of patients and not 30.7%. This error should be corrected in the paper. It would be informative to provide the range for patient body mass index (BMI), in addition to the median BMI, which might be useful when selecting patients for DTI prepectoral reconstruction with polyurethane-coated implants. DTI reconstructions are usually recommended in small- or medium-breasted females, and this was an inclusion criterion in this study as well.

The authors used standardized outcome assessments, which is commendable. In the absence of head-to-head comparative studies, standardized assessments provide a means for comparing between studies.

Overall, this study contributes to the evidence base on the safety and feasibility of using polyurethane-coated implants in breast reconstruction and in particular DTI reconstruction. By reducing the risk of capsular contracture and implant malposition, these implants behave similarly to ADMs. Their continued unavailability in the United States is unfortunate.

Disclosures

Dr Gabriel is a consultant for Allergan (Irvine, CA) and 3 M (Minneapolis, MN). Dr Maxwell receives royalties for licensed intellectual property from AbbVie, Inc. (Madison, NJ).

Funding

The authors received no financial support for the research, authorship, and publication of this article.

Author notes

Dr Gabriel is a clinical professor of surgery, Department of Plastic Surgery, Loma Linda University Medical Center, Loma Linda, CA, USA.

Dr Maxwell is a clinical professor of surgery, Department of Plastic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.