Beyond the Trade-Off: Achieving High Spatial and Temporal Resolution in Breast DCE-MRI Using a Novel 4D Stack-of-Stars Sequence.

RATIONALE AND

OBJECTIVES

To clinically implement and evaluate a 4D diamond-shaped pseudo-golden angle stack-of-stars acquisition with k-space weighted image contrast reconstruction for breast dynamic contrast-enhanced MRI (4D-DCE), assessing image quality, diagnostic confidence, and Breast Imaging Reporting and Data System (BI-RADS) agreement across conventional and ultrafast protocols.

MATERIAL AND

METHODS

This retrospective study included female patients who underwent breast MRI at 3 T using the 4D-DCE sequence. Three protocol types were generated: (1) conventional (4 × 60 s), (2) ultrafast (20 × 3 s), and (3) combined (ultrafast followed by 3 × 60 s). Two readers independently or in consensus rated image quality (overall quality, artifacts, sharpness, lesion conspicuity, and morphology) and diagnostic confidence using a 5-point Likert scale. BI-RADS scores were compared to the final reference standard (histology or ≥2-year imaging follow-up). Agreement was assessed using Cohen's kappa.

RESULTS

A total of 167 patients (mean age: 59 ± 11 years) were included. Despite high temporal resolution of the ultrafast 4D-DCE, image quality was good to excellent and was comparable to the standard-resolution post-contrast T1 mDixon sequence (e.g., overall quality: 4.8 ± 0.4 vs. 4.8 ± 0.3, P =0.99). The combined 4D-DCE protocol yielded the highest diagnostic confidence by BI-RADS assignment in both readers, with the most pronounced improvement observed in patients with high background parenchymal enhancement (e.g., reader 1: 3.2 ± 0.6 [conventional] vs. 4.2 ± 0.4 [ultrafast] vs. 4.9 ± 0.3 [combined], P <0.001). BI-RADS agreement with the final reference standard was good to excellent across all DCE protocols, with the highest agreement achieved using the combined 4D-DCE (e.g., reader 1: κ = 0.89, 95% CI: 0.84-0.95).

CONCLUSION

The proposed 4D-DCE technique enables robust breast DCE-MRI with high spatial and temporal resolution. Combining ultrafast and conventional acquisitions within a single protocol improves diagnostic confidence and BI-RADS agreement.