66. Predicting Final Breast Implant Size Using Tissue Expander Characteristics - A 10-Year Institutional Data

PURPOSE: Implant based reconstruction is the most performed type of breast reconstruction in the US. Among these, two-staged reconstruction constitutes about 72% of the total reconstructions. Two-staged breast reconstruction requires the initial placement of tissue expander TE, before the breast implant is subsequently placed in another operation. Predicting the appropriate breast implant size has remained a challenge, as there is no standardized way to determine this before the surgery. Surgeons order more than 50 implants per surgery to determine the most appropriate ones. There is paucity of studies that used TE based characteristics to narrow the number of permanent implant trial per reconstruction surgery. Atia et al recently used TE and Implant characteristics to devise a final formula that predicts the choice of implant in patients undergoing prepectoral breast reconstruction. This was the first published work using this widely accepted method of breast reconstruction. Previously, Gabrick et al had done similar work in patients undergoing submuscular implant-based breast reconstruction. These have enabled surgeons and patients to streamline and minimize how many implants is ordered per breast implant surgery. Since the prepectoral breast reconstruction type became more popular due to a better safety profile compared to the submuscular type, there is need to streamline the ordering of implants, to save cost, and provide better operative guide for surgeons. Objectives and Outcomes-To identify tissue expander characteristics that will predict implant choice, helping to guide surgeons intra-operatively as well as help to minimize the number of implant devices that need to be ordered in preparation for an exchange procedure.-To use these identified characteristics to devise a formula and an algorithm that will inform reduction in the number of implants that need to be ordered in preparation for an exchange procedure. METHODS: A retrospective chart review of all adult female patients who have undergone two-staged prepectoral breast reconstruction at the Department of Plastic Surgery, Ohio State University between 2015-2022, is currently being conducted. Data elements being extracted includes patients’ demographics, pre- and postoperative data, TE characteristics (TE initial and final fill volume, TE type, TE size including height, width, and weight,) Implant characteristics (Implant chosen, implant size, height and width, implant volume and projection). Covariates including surgeon’s experience and patients’ preferences are also be taken into consideration. RESULTS: Approximately 800 patients are being included in this study. A univariate linear regression is used to identify TE properties and other predictive variables, while multivariate analysis, after correcting for covariates is being used to devise a predictive formula. CONCLUSIONS: We believe that this is a very important study that will streamline breast surgeons and patients’ efforts in their final implant choices. This study utilizes data from about 10-year of an institutional experience, which means the temporal changes and trends in TE and implant designs will also be put into account.