Objective: Breast density reflects fibroglandular tissue composition and affects imaging interpretation and cancer risk. Ultrasound (US) shear-wave elastography (SWE) offers a quantitative method for assessing tissue stiffness. This study aimed to investigate the correlation between breast parenchymal stiffness values measured by SWE and attenuation values obtained from computed tomography (CT).
Materials and
Methods: Fifty-four female patients who underwent both breast SWE and chest CT were evaluated. SWE stiffness (kilopascal, kPa) and CT attenuation (Hounsfield Units [HU]) were measured from corresponding parenchymal regions. Correlations were analyzed using Pearson’s and Spearman’s coefficients, and linear regression analysis was performed.

Results: The mean CT attenuation was −24.8±30.1 HU, and the mean SWE stiffness was 11.7±3.1 kPa. SWE stiffness progressively increased with higher breast parenchymal types according to the Breast Imaging Reporting and Data System classification. CT attenuation and SWE stiffness values demonstrated a strong positive correlation (r=0.91, p<0.001).

Conclusion: SWE stiffness values strongly correlate with CT attenuation and may serve as a radiation-free surrogate marker for quantitative assessment of breast parenchymal density.