Work

179. Breaking the Mold: How Antibiotic Beads Shape Breast Capsule Formation in Tissue Expander Based Breast Reconstruction

Year: 2025

Type: article

Abstract: PURPOSE: Absorbable antibiotic beads are emerging as a novel technique for preventing infections in tissue expander (TE)-based breast reconstruction. However, the impact of absorbable antibiotic beads on breast capsule formation remains unclear. The aim of this study was to analyze the gross and histological characteristics of breast capsules in patients who underwent TE-based reconstruction with and without absorbable antibiotic beads. METHODS: This was a prospective, single-surgeon study of patients undergoing mastectomy and immediate pre-pectoral TE placement with and without antibiotic beads from 2022 to 2024. Antibiotic beads, made with 1 gram of vancomycin and 240 milligrams of gentamicin, were placed in the breast pocket intraoperatively following TE placement. Antibiotic beads were introduced into the practice in October 2023 and each patient after that date received beads. Breasts that received radiation therapy were excluded. At the time of second stage reconstruction, samples of the posterior capsule were collected and analyzed. A pathologist blinded to antibiotic bead treatment analyzed histological slides for maximum width of collagen layer, fiber organization, lymphocytic infiltration, and presence of calcification. The Wilcoxon rank-sum test was used to compare the two groups using an alpha level of 0.05. RESULTS: Our study included 41 breasts from 24 patients, including 16 breasts without antibiotic beads and 25 breasts with antibiotic beads. Both groups were comparable in age and body mass index (BMI), with a median age of 46 years and a median BMI of 21.5 kg/m2. Both groups were also comparable in mastectomy weights, with a median mastectomy weight of 300g (range: 160g-800g). Breasts without beads had significantly thicker capsules compared to those with beads (median: 5.5mm, range: 1mm-28mm versus 2mm, range: 1mm-11mm, p = 0.004). Histological analysis was conducted on 10 representative breast capsules (5 without beads and 5 with beads). The median collagen layer width for breasts without beads was 3.5mm (range: 2mm-5.1mm), compared to 2.5mm (range: 1.1mm-3.2mm) for breasts with beads, although this difference was not statistically significant (p = 0.11). Regarding fiber organization, two of the five capsules without beads had highly organized fibers, and three had moderately disorganized fibers. In contrast, four of the five capsules with beads had highly organized fibers, and one had moderately disorganized fibers. Lymphocytic inflammation was observed in three of the five capsules without beads, while two of the five capsules with beads showed this feature. Finally, calcification was present in two of the five capsules with beads but in none of the capsules without beads. CONCLUSION: Our findings suggest that the use of antibiotic beads in device-based breast reconstruction significantly decreases gross capsule thickness. Despite limitations to our study, including small sample size, this pilot work indicates that antibiotic beads may lead to variations in collagen layer width, fiber organization, inflammatory response, and calcification. These variations may have important implications for long-term outcomes in device reconstruction, such as the risk of clinical contracture.

Source: Plastic & Reconstructive Surgery Global Open

DOI: 10.1097/01.gox.0001112664.49390.20