The Best Under Stress: An Analysis of Breast Tissue Expander Response to External Forces

Abstract

Background The use of breast tissue expanders (TE) in breast reconstruction is accompanied by undesired changes to the chest wall and lateral plane. Breast TEs are designed to create a naturally formed breast pocket by capitalizing on the ductile response of skin tissue; however, in practice, the use of expanders is accompanied by undesired changes to the chest wall and lateral plane. Objectives The authors of this study compared 3 comparably sized and commercially available breast TEs to assess the mechanical profile and functionality of each design. Methods Authors compared MENTOR Artoura PLUS Smooth (Irvine, CA), Allergan 133 Smooth (Irvine, CA), and Sientra AlloX2 Smooth (Santa Barbara, CA) filled to 100% of their label volume. The mechanical profile of TEs was assessed via vertical compression. Dimensions were recorded at baseline and percent changes were calculated at each compressive load (5-35 lbf intervals of 5 lbf). Results Base width and projection were recorded at compressive loads of 10, 20, and 35 lbs. For percent changes of base width, MENTOR had 0.98%, 2.09%, 3.84%; Allergan 4.21%, 9.15%, 15.52%; and Sientra 4.72%, 10.19%, 19.15%. For percent changes of projection, MENTOR® had -19.06%, -25.44%, -30.88%, Allergan -35.53%, -42.90%, -50.09%, and Sientra® -29.64%, -37.68%, -44.69%. For percent change of height, MENTOR had 1.44%, 2.62%, 4.27%, Allergan 10.26%, 16.49%, 22.97%, and Sientra 6.99%, 11.93%, 16.90%. MENTOR’s TE had the most pronounced lower pole with volume expansion. Conclusions The MENTOR TE demonstrated the least lateral deformation and projection loss across the range of compressive loads, as well as the highest force resistance compared to the other models.

Safety Profile Comparison of 2 Smooth Tissue Expander Types

“…With the addition of this feature, the Artoura purports to offer more consistent and predictable outcomes of pocket formation 9 . Najafali et al demonstrated that with applied mechanical compression forces, Artoura TEs have the least lateral distortion and forward projection loss when compared with other TE 10 …”

“…9 Najafali et al demonstrated that with applied mechanical compression forces, Artoura TEs have the least lateral distortion and forward projection loss when compared with other TE. 10 Although the literature on breast TEs in general has been well studied, few studies have investigated the complications associated with specific TE subtypes, particularly since the larger adoption of smooth models. It remains unclear what actual differences, if any, exist practically between different models.…”

Commentary on: The Best Under Stress: An Analysis of Breast Tissue Expander Response to External Forces

“…This experimental study was designed to test the deformational properties of 3 commercially available breast tissue expanders distributed by Mentor (Irvine, CA), Allergan (Irvine, CA), and Sientra (Santa Barbara, CA). 1 The purpose was to determine if various compressive loads, when applied to a fully filled saline tissue expander, would result in deformation based on base width, projection, and height. The implication being that this could affect clinical outcomes.…”

Response to: Commentary on: The Best Under Stress: An Analysis of Breast Tissue Expander Response to External Forces

“…We appreciate the reader's input and thoughtful commentary on our recent article on the deformational forces of 3 commercially available tissue expanders (TEs). 1 , 2 The author raises a valid point that advancements in reconstructive plane utilized, namely prepectoral, alter the intracorporal forces on a TE. This is an excellent observation of changes in practice and procedural technique which has influenced the impact of the pectoralis major muscle on the breast soft-tissue pocket.…”