Valutazione dell'attenuazione monoenergetica del silicone da protesi mammaria nelle acquisizioni TC in Dual Energy

The aim of this study was to evaluate whether Dual Energy Computed Tomography (DECT) is able to characterize the silicone contained in breast implants, identifying the most suitable acquisition parameters and the most convenient energy range to maximize silicone detection compared to surrounding tissues. An anthropomorphic phantom, with two different types of breast implants positioned over the thoracic area, was scanned with sequential acquisitions using multiple kV ranges (70–150 Sn kV, 80–150 Sn kV, 80–140 kV, 90–150 Sn kV, 100–150 Sn kV). All series were reconstructed at both 0.6 mm and 1.0 mm thickness. Five Regions of Interest (ROIs) were placed in specific areas, inside and outside the phantom, and the extracted data were used to calculate the Contrast-to-Noise Ratio (CNR) between silicone and surrounding tissues and enviroment. This procedure was repeated across all acquisition ranges, and the mean CNR values were compared. Quantitative evaluations demonstrated that higher CNR values were obtained at lower energy ranges (70–150 Sn kV), with 1.0 mm reconstructions providing better stability and less noise than 0.6 mm. Silicone detection was optimal in low and intermediate density environments (air, soft tissues), whereas in high density tissues (bone) the signal appeared minimal or even negative, limiting the visibility of the material itself. No statistically significant differences were observed between the data of the two types of implants. Overall, DECT was effective in detecting and characterizing silicone within breast implants, with the best results obtained using low-energy settings and thicker reconstructions. However, the reduced detectability near high-density tissues remains a limitation. These findings suggest the optimal acquisition parameters for further studies and highlight the potential of DECT as a valuable tool in the evaluation of breast implants, instead pd MRI for patients with controindications to the latter.