Multiparametric comparison of low-energy contrast-enhanced mammography and full-field digital mammography for image quality and lesion conspicuity using EUREF standards and Likert scoring.

Purpose: To determine whether low-energy (LE) images acquired during contrast-enhanced mammography (CEM) are diagnostically and technically comparable to full-field digital mammography (FFDM) using standardised image quality and lesion conspicuity metrics.

Materials and methods: In this retrospective study, 268 women (mean age: 44.6 years) who underwent both FFDM and CEM imaging, were included. Three blinded radiologists independently assessed the FFDM and LE-CEM images using 20-point EUREF (European Reference Organisation for Quality Assured Breast Screening and Diagnostic Services) criteria and 5-point Likert scale for image quality, lesion conspicuity, margin clarity, and diagnostic adequacy. An analysis of the additional lesion detection rate was done. Additionally, technical metrics including posterior nipple line (PNL), compressed breast thickness (CBT), and average glandular dose (AGD) were also recorded. Statistical analysis included Wilcoxon signed-rank, McNemar's test, intraclass correlation coefficient (ICC), and Fleiss' kappa.

Results: LE images scored significantly higher than FFDM in 11 of 20 EUREF parameters (p < 0.05) and were non-inferior in the remaining. Median Likert scores were significantly higher for LE images across all lesion parameters, including conspicuity against background (5 vs. 4), margin clarity (5 vs. 4), and overall lesion visibility (5 vs. 4) (all p < 0.001). LE images detected significantly more lesions per patient (0.557 vs. 0.314; p < 0.001) with excellent inter-reader agreement (κ > 0.80). PNL and CBT showed near-perfect positional reproducibility (ICC > 0.98), and all AGD values remained within EUREF safety limits.

Conclusion: LE-CEM images match or rather exceed FFDM in image quality, lesion detection, and diagnostic adequacy, while maintaining technical reproducibility. These findings support omitting additional FFDM exposure in patients with indications for CEM, thereby reducing radiation dose and streamlining the workflow.