Tissue Expander Breast Reconstruction Study on Breast Volume and Shape Change

Overview

The purpose of this study is to explore the volume change and location of volume change in reconstructed breasts using the Contour Profile® tissue expander. Our purpose is also to investigate the safety of using CPX3® in tissue-expander breast reconstruction via a comparison between the complication rates that result from this study and the complication rates with the use of other tissue expander types, as reported in the literature. We also hope to demonstrate the use of 3-D imaging technology as an objective measure of upper and lower breast volume change and location of this volume change in the reconstructed breast. Finally, we intend to provide reconstructive surgeons with a scientific study that quantifies the patient satisfaction with aesthetic results of CPX3 in tissue expander-implant breast reconstruction. We hypothesize that the CPX3 tissue expander will provide more lower pole volume expansion when compared to lower pole volume expansion from round, standard tissue expanders as reported in the literature. Additionally, we hypothesize that CPX3, in combination with human acellular dermis, is less prone to complications than standard tissue expanders (again, as reported in the literature).

Tissue expansion is an accepted and widely used method for breast reconstruction. A drawback in using standard tissue expanders is unwanted fullness at the upper pole and insufficient expansion at the lower pole of the breast. Round expanders can result in poor ptosis (sagging) because of unwanted upper pole fullness and are not without risk for complications\[1, 2\]. Anatomically-shaped expanders also have shortcomings and complications such as malposition\[3-7\]. A tissue expander designed to counteract upper pole fullness is necessary to achieve a more natural appearing ptotic breast with a well-defined inframammary fold (IMF)\[8\]. The inframammary fold is the crease below the breast where the breast meets the chest wall. Mentor's Contour Profile® (CPX3) tissue expander provides a design with a greater height to width ratio for greater lower pole expansion. It also has suture tabs on the back of the expander to hold the expander in place and prevent malposition. Another recent advancement in tissue expander breast reconstruction is the use of cadaveric-derived human acellular dermis for rapid intraoperative expansion and early projection\[9-14\]. The crescent-shaped expander has been studied by John YS Kim, MD in a retrospective review of 40 consecutive patients who underwent acellular dermis assisted breast reconstruction. He found the crescentric tissue expansion with acellular dermis is well tolerated with high patient and surgeon satisfaction likely due to selective lower pole expansion related to the crescent shape, as well as significant immediate expansion related to larger subpectoral pockets. To date, no studies have been reported that investigate the lower pole expansion resulting from varying tissue expander dimensions with objective computer software\[15, 16\]. The advent of three-dimensional imaging technology to objectively measure lower pole expansion provides a quantitative means to study the advantages of using the CPX3® tissue expander. We propose a study that will show whether or not the CPX3® tissue expander's unique design can have an ultimate effect on the shape and location of volume change on the postoperative breast. Three-dimensional cameras also provide an advantage for assessing patients undergoing bilateral mastectomy and reconstruction who desire a reconstructive outcome that will bear some resemblance to their current breasts \[15\]. The 3-D imaging calculation evaluates the following parameters: absolute volume, absolute volume change, location of expansion, base width, breast projection and contour symmetry. Older methods of volume assessment would assume that the base of the breast is a flat plane. The Vectra system takes into account the curvature of the chest wall, which results in a more accurate breast volume measurement. With 3-D imaging there is no exposure to radiation\[16\]. Another advantage to 3-D imaging is the option to view the subject's image at any angle, 360 degrees\[17\]. Our study would show the postoperative results of using the CPX3® tissue expander with an objective analysis of the degree of lower-pole expansion. This will be a prospective study. Fifteen patients will be enrolled and will receive a Contour profile tissue expander (CPX3) during their reconstruction.