Valutazione dell'attenuazione delle acquisizioni DECT da silicone da protesi mammaria su fantoccio antropomorfo

Objectives: to evaluate the capability of Dual Energy Computed Tomography (DECT) in characterizing silicone breast implants, including the identification of the best technical parameters to maximize silicone detection in a simulated clinical setting (anthropomorphic phantom). Materials and Methods: an anthropomorphic phantom -with two different implants placed on the chest area- was scanned using multiple DECT acquisitions with all available kV ranges (70-150, 80-150, 90-150, 100-150, 80-140) and a 0,6- or 1 mm reconstruction thickness. Elaborations were performed by “Syngo.via” software using the Liver VNC application class and its profiles (VNC, CM, Mixed, Low kV, High kV); Rho/Z class did not allow same analysis as similar parameters were not available. Quantitative assessment was carried out by calculating the contrast-to-noise-ratio (CNR) between silicone and surrounding phantom tissues. Results: the highest mean CNR values for silicone were obtained with the 70-150 kV range and 1 mm thickness. Detection was optimal if compared to low- and medium-low- density tissues, while values were close to zero or negative if compared to high-density tissues such as bone. Mixed and Low kV profiles were the best to obtain high mean CNR values. No significant differences were observed between the two implants. Discussion and Conclusions: DECT demonstrated the ability to characterize silicone breast implants, especially with wide spectral separations such as 70-150 and 80-150 or 90-150 that would fit the best clinical approach. A reduced reconstruction thickness was associated with lower CNR values due to increased image noise. The best application profiles were Mixed and Low kV. However, DECT has shown significant limitations in high-density environments, where sensitivity decreases significantly.